Research and development of leading, fundamental energy-saving techniques. Report on the R and D of coal-fired magneto-hydro-dynamics (MHD) electrical power generation (Prompt report by Electrotechnical Laboratory); Sekitan nensho MHD hatsuden no kenkyu ni kansuru seika hokoku. Densoken kenkyu sokuho

Energy Technology Data Exchange (ETDEWEB)

NONE

1990-03-30

Summarized herein are the reports on the R and D of coal-fired magneto-hydro-dynamics (MHD) electrical power generation, received by March 30, 1990. For the coal combustor, the air flow tests have been conducted using a 5MW-scale plastic model since 1984, and the model has been later scaled-up to 15MW. The actual combustion tests have been conducted using a 1MW-scale combustor, designed based on the results of air flow tests using the 15MW-scale model, mainly for the cyclone combustor in the first stage. For a coal-fired generation channel, the studies on the cathodes and insulation walls have been conducted since 1986, the research themes including causes for and measures against inter-cathode shorting, and insulating walls of SiC. The anode walls have been studied since 1986, deepening understanding of, e.g., the anode arc phenomenon and anode discharge phenomenon which relates to the causes for exhaustion of the inter-anode insulators and anode materials. For the high temperature regenerative heat exchanger, the existing materials have been screened since 1985, and the basic data related to, e.g., slag viscosity and its effects on material corrosion have been collected since 1986. (NEDO)

Chaotic dynamic characteristics of pressure fluctuation signals in hydro-turbine

Energy Technology Data Exchange (ETDEWEB)

Su, Wen Tao; An, Shi [School of Management, Harbin Institute of Technology, Harbin (China); Li, Xiao Bin; Lan, Chao Feng; Li, Feng Chen [School of Energy Science and Engineering, Harbin Institute of Technology, Harbin (China); Wang, Jian Sheng [Ministry of Education of China, Tianjin (China)

2016-11-15

The pressure fluctuation characteristics in a Francis hydro-turbine running at partial flow conditions were studied based on the chaotic dynamic methods. Firstly, the experimental data of pressure fluctuations in the draft tube at various flow conditions was de-noised using lifting wavelet transformation, then, for the de-noised signals, their spectrum distribution on the frequency domain, the energy variation and the energy partition accounting for the total energy was calculated. Hereby, for the flow conditions ranging from no cavitation to severe cavitation, the chaos dynamic features of fluctuation signals were analyzed, including the temporal-frequency distribution, phase trajectory, Lyapunov exponent and Poincaré map etc. It is revealed that, the main energy of pressure fluctuations in the draft tube locates at low-frequency region. As the cavitation grows, the amplitude of power spectrum at frequency domain becomes larger. For all the flow conditions, all the maximal Lyapunov exponents are larger than zero, and they increase with the cavitation level. Therefore, it is believed that there indeed exist the chaotic attractors in the pressure fluctuation signals for a hydro-turbine.

Dynamic Model for Hydro-Turbine Generator Units Based on a Database Method for Guide Bearings

Directory of Open Access Journals (Sweden)

Yong Xu

2013-01-01

Full Text Available A suitable dynamic model of rotor system is of great significance not only for supplying knowledge of the fault mechanism, but also for assisting in machine health monitoring research. Many techniques have been developed for properly modeling the radial vibration of large hydro-turbine generator units. However, an applicable dynamic model has not yet been reported in literature due to the complexity of the boundary conditions and exciting forces. In this paper, a finite element (FE rotor dynamic model of radial vibration taking account of operating conditions is proposed. A brief and practical database method is employed to model the guide bearing. Taking advantage of the method, rotating speed and bearing clearance can be considered in the model. A novel algorithm, which can take account of both transient and steady-state analysis, is proposed to solve the model. Dynamic response for rotor model of 125 MW hydro-turbine generator units in Gezhouba Power Station is simulated. Field data from Optimal Maintenance Information System for Hydro power plants (HOMIS are analyzed compared with the simulation. Results illustrate the application value of the model in providing knowledge of the fault mechanism and in failure diagnosis.

Rate-dependent extensions of the parametric magneto-dynamic model with magnetic hysteresis

Directory of Open Access Journals (Sweden)

S. Steentjes

2017-05-01

Full Text Available This paper extends the parametric magneto-dynamic model of soft magnetic steel sheets to account for the phase shift between local magnetic flux density and magnetic field strength. This phase shift originates from the damped motion of domain walls and is strongly dependent on the microstructure of the material. In this regard, two different approaches to include the rate-dependent effects are investigated: a purely phenomenological, mathematical approach and a physical-based one.

Magneto-optic dynamics in a ferromagnetic nematic liquid crystal

Science.gov (United States)

Potisk, Tilen; Mertelj, Alenka; Sebastián, Nerea; Osterman, Natan; Lisjak, Darja; Brand, Helmut R.; Pleiner, Harald; Svenšek, Daniel

2018-01-01

We investigate dynamic magneto-optic effects in a ferromagnetic nematic liquid crystal experimentally and theoretically. Experimentally we measure the magnetization and the phase difference of the transmitted light when an external magnetic field is applied. As a model we study the coupled dynamics of the magnetization, M , and the director field, n , associated with the liquid crystalline orientational order. We demonstrate that the experimentally studied macroscopic dynamic behavior reveals the importance of a dynamic cross-coupling between M and n . The experimental data are used to extract the value of the dissipative cross-coupling coefficient. We also make concrete predictions about how reversible cross-coupling terms between the magnetization and the director could be detected experimentally by measurements of the transmitted light intensity as well as by analyzing the azimuthal angle of the magnetization and the director out of the plane spanned by the anchoring axis and the external magnetic field. We derive the eigenmodes of the coupled system and study their relaxation rates. We show that in the usual experimental setup used for measuring the relaxation rates of the splay-bend or twist-bend eigenmodes of a nematic liquid crystal one expects for a ferromagnetic nematic liquid crystal a mixture of at least two eigenmodes.

A Possible Universe in Pulsation by Using a Hydro-Dynamical Model for Gravity

Directory of Open Access Journals (Sweden)

Corneliu BERBENTE

2016-12-01

Full Text Available By using a hydro-dynamical model for gravity previously given by the author, a pulsating universe is possible to describe. This is possible because two hydro-dynamical sources are in attraction both when they are emitting and absorbing fluid. In our model, bodies (matter and energy are interacting via an incompressible fluid made of gravitons (photon-like particles having a wave length of the order of magnitude of the radius of universe. One considers the universe uniform at large scale, the effects of general relativity type being local and negligible at global scale. An “elastic sphere” model for the universe is suggested to describe the possible inversion. The expansion of the universe stops when the “elastic energy” overcomes the kinetic one; this takes place near the point of maximal emission speed of the fluid of gravitons. The differential equation for the universe in expansion is adapted to contraction. Analytical solutions are given.

Hydro-dynamic damping theory in flowing water

Science.gov (United States)

Monette, C.; Nennemann, B.; Seeley, C.; Coutu, A.; Marmont, H.

2014-03-01

Fluid-structure interaction (FSI) has a major impact on the dynamic response of the structural components of hydroelectric turbines. On mid-head to high-head Francis runners, the rotor-stator interaction (RSI) phenomenon always has to be considered carefully during the design phase to avoid operational issues later on. The RSI dynamic response amplitudes are driven by three main factors: (1) pressure forcing amplitudes, (2) excitation frequencies in relation to natural frequencies and (3) damping. The prediction of the two first factors has been largely documented in the literature. However, the prediction of fluid damping has received less attention in spite of being critical when the runner is close to resonance. Experimental damping measurements in flowing water on hydrofoils were presented previously. Those results showed that the hydro-dynamic damping increased linearly with the flow. This paper presents development and validation of a mathematical model, based on momentum exchange, to predict damping due to fluid structure interaction in flowing water. The model is implemented as an analytical procedure for simple structures, such as cantilever beams, but is also implemented in more general ways using three different approaches for more complex structures such as runner blades: a finite element procedure, a CFD modal work based approach and a CFD 1DOF approach. The mathematical model and all three implementation approaches are shown to agree well with experimental results.

A fully dynamic magneto-rheological fluid damper model

International Nuclear Information System (INIS)

Jiang, Z; Christenson, R E

2012-01-01

Control devices can be used to dissipate the energy of a civil structure subjected to dynamic loading, thus reducing structural damage and preventing failure. Semiactive control devices have received significant attention in recent years. The magneto-rheological (MR) fluid damper is a promising type of semiactive device for civil structures due to its mechanical simplicity, inherent stability, high dynamic range, large temperature operating range, robust performance, and low power requirements. The MR damper is intrinsically nonlinear and rate-dependent, both as a function of the displacement across the MR damper and the command current being supplied to the MR damper. As such, to develop control algorithms that take maximum advantage of the unique features of the MR damper, accurate models must be developed to describe its behavior for both displacement and current. In this paper, a new MR damper model that includes a model of the pulse-width modulated (PWM) power amplifier providing current to the damper, a proposed model of the time varying inductance of the large-scale 200 kN MR dampers coils and surrounding MR fluid—a dynamic behavior that is not typically modeled—and a hyperbolic tangent model of the controllable force behavior of the MR damper is presented. Validation experimental tests are conducted with two 200 kN large-scale MR dampers located at the Smart Structures Technology Laboratory (SSTL) at the University of Illinois at Urbana-Champaign and the Lehigh University Network for Earthquake Engineering Simulation (NEES) facility. Comparison with experimental test results for both prescribed motion and current and real-time hybrid simulation of semiactive control of the MR damper shows that the proposed MR damper model can accurately predict the fully dynamic behavior of the large-scale 200 kN MR damper. (paper)

Magneto-structural coupling and harmonic lattice dynamics in CaFe2As2 probed by Moessbauer spectroscopy

International Nuclear Information System (INIS)

Li Zhiwei; Ma Xiaoming; Pang Hua; Li Fashen

2011-01-01

In this paper we present a detailed Moessbauer spectroscopy study of the structural and magnetic properties of the undoped parent compound CaFe 2 As 2 single crystal. By fitting the temperature dependence of the hyperfine magnetic field we show that the magneto-structural phase transition is clearly first order in nature and we also deduce the compressibility of our sample to be 1.67 x 10 -2 GPa -1 . Within Landau's theory of phase transition, we further argue that the observed phase transition may stem from the strong magneto-structural coupling effect. The temperature dependence of the Lamb-Moessbauer factor shows that the paramagnetic phase and the antiferromagnetic phase exhibit similar lattice dynamics in high-frequency modes with very close Debye temperatures, Θ D ∼ 270 K.

Development and applications of reactor noise analysis at Ontario Hydro`s CANDU reactors

Energy Technology Data Exchange (ETDEWEB)

Gloeckler, O [Ontario Hydro, Toronto, ON (Canada); Tulett, M V [Ontario Hydro, Pickering, ON (Canada). Pickering Generating Station

1996-12-31

In 1992 a program was initiated to establish reactor noise analysis as a practical tool for plant performance monitoring and system diagnostics in Ontario Hydro`s CANDU reactors. Since then, various CANDU-specific noise analysis applications have been developed and validated. The noise-based statistical techniques are being successfully applied as powerful troubleshooting and diagnostic tools to a wide variety of actual operational I and C problems. The dynamic characteristics of critical plant components, instrumentation and processes are monitored on a regular basis. Recent applications of noise analysis include (1) validating the dynamics of in-core flux detectors (ICFDS) and ion chambers, (2) estimating the prompt fraction ICFDs in noise measurements at full power and in power rundown tests, (3) identifying the cause of excessive signal fluctuations in certain flux detectors, (4) validating the dynamic coupling between liquid zone control signals, (5) detecting and monitoring mechanical vibrations of detector tubes induced by moderator flow, (6) estimating the dynamics and response time of RTD (Resistance Temperature Detector) temperature signals, (7) isolating the cause of RTD signal anomalies, (8) investigating the source of abnormal flow signal behaviour, (9) estimating the overall response time of flow and pressure signals, (10) detecting coolant boiling in fully instrumented fuel channels, (11) monitoring moderator circulation via temperature noise, and (12) predicting the performance of shut-off rods. Some of these applications are performed on an as-needed basis. The noise analysis program, in the Pickering-B station alone, has saved Ontario Hydro millions of dollars during its first three years. The results of the noise analysis program have been also reviewed by the regulator (Atomic Energy Control Board of Canada) with favorable results. The AECB have expressed interest in Ontario Hydro further exploiting the use of noise analysis technology. (author

Dynamic characterization and modeling of magneto-rheological elastomers under compressive loadings

International Nuclear Information System (INIS)

Koo, J H; Khan, F; Jang, D D; Jung, H J

2009-01-01

The primary goal of this paper is to characterize and model the compression properties of Magneto-Rheological Elastomers (MREs). MRE samples were fabricated by curing a two component elastomer resin with 30% content of 10 μm sized iron particles by volume. In order to vary the magnetic field during compressive testing, a test fixture was designed and fabricated in which two permanent magnets could be variably positioned on either side of the specimen. By changing the distance between the magnets, the fixture allowed for varying the magnetic field that passes uniformly through the sample. Using this test setup and a dynamic test frame, a series of compression tests of MRE samples was performed by varying the magnetic field and frequency of loading. The results show the MR effect (percent increase in the materials 'stiffness') increases as the magnetic field increases and loading frequency increases within the range of the magnetic field and input frequency considered in this study. Furthermore, a phenomenological model was developed to capture the dynamic behaviours of the MREs under compression loadings.

Magnetic-Laval-Nozzle Effect on a Magneto-Plasma-Dynamic Arcjet

International Nuclear Information System (INIS)

Inutake, Masaaki; Miyazaki, Hiroyuki; Yoshino, Kyohei; Tobari, Hiroyuki; Hattori, Kunihiko; Ando, Akira

2003-01-01

A magneto-plasma-dynamic arcjet (MPDA) is one of the promising candidates for a manned interplanetary space thruster with a higher specific impulse and larger thrust. An MPDA with an externally-applied magnetic nozzle is investigated to improve the thrust efficiency. From spectroscopic measurements of the MPDA plasma, it is found that with the increase in the discharge current not only the flow velocity but also the ion temperature increase near the muzzle of the MPDA with a uniform axial magnetic field and so the ion acoustic Mach number is limited to a value less than unity. By installing a Laval-type magnetic nozzle near the muzzle of the MPDA, the subsonic flow is successfully accelerated to a supersonic one by converting the ion thermal energy to the flow energy. The results are compared with the prediction by a1-D isentropic flow model

Dynamic characterization and modeling of magneto-rheological elastomers under compressive loadings

International Nuclear Information System (INIS)

Koo, Jeong-Hoi; Khan, Fazeel; Jang, Dong-Doo; Jung, Hyung-Jo

2010-01-01

The primary goal of the research reported in this paper has been to characterize and model the compression properties of magneto-rheological elastomers (MREs). MRE samples were fabricated by curing a two-component elastomer resin with 30% content of 10 µm sized iron particles by volume. In order to vary the magnetic field during compressive testing, a test fixture was designed and fabricated in which two permanent magnets could be variably positioned on either side of the specimen. Changing the distance between the magnets of the fixture allowed the strength of the magnetic field passing uniformly through the sample to be varied. Using this test setup and a dynamic test frame, a series of compression tests of MRE samples were performed, by varying the magnetic field and the frequency of loading. The results show that the MR effect (per cent increase in the material 'stiffness') increases as the magnetic field increases and the loading frequency increases within the range of the magnetic field and input frequency considered in this study. Furthermore, a phenomenological model was developed to capture the dynamic behaviors of the MREs under compression loadings. (technical note)

Dynamic analysis of electro- and magneto-rheological fluid dampers using duct flow models

International Nuclear Information System (INIS)

Esteki, Kambiz; Bagchi, Ashutosh; Sedaghati, Ramin

2014-01-01

Magneto-rheological (MR) and electro-rheological (ER) fluid dampers provide a semi-active control mechanism for suppressing vibration responses of a structure. MR and ER fluids change their viscosity under the influence of magnetic and electrical fields, respectively, which facilitates automatic control when these fluids are used in damping devices. The existing models, namely the phenomenological models for simulating the behavior of MR and ER dampers, rely on various parameters determined experimentally by the manufacturers for each damper configuration. It is of interest to develop mechanistic models of these dampers which can be applied to various configurations so that their fundamental characteristics can be studied to develop flexible design solutions for smart structures. This paper presents a formulation for dynamic analysis of electro-rheological (ER) and magneto-rheological (MR) fluid dampers in flow and mix mode configurations under harmonic and random excitations. The procedure employs the vorticity transport equation and the regularization function to deal with the unsteady flow and nonlinear behavior of ER/MR fluid in general motion. The finite difference method has been used to solve the governing differential equations. Using the developed approach, the damping force of ER/MR dampers can be calculated under any type of excitation. (paper)

Optimal control systems in hydro power plants

International Nuclear Information System (INIS)

Babunski, Darko L.

2012-01-01

The aim of the research done in this work is focused on obtaining the optimal models of hydro turbine including auxiliary equipment, analysis of governors for hydro power plants and analysis and design of optimal control laws that can be easily applicable in real hydro power plants. The methodology of the research and realization of the set goals consist of the following steps: scope of the models of hydro turbine, and their modification using experimental data; verification of analyzed models and comparison of advantages and disadvantages of analyzed models, with proposal of turbine model for design of control low; analysis of proportional-integral-derivative control with fixed parameters and gain scheduling and nonlinear control; analysis of dynamic characteristics of turbine model including control and comparison of parameters of simulated system with experimental data; design of optimal control of hydro power plant considering proposed cost function and verification of optimal control law with load rejection measured data. The hydro power plant models, including model of power grid are simulated in case of island ing and restoration after breakup and load rejection with consideration of real loading and unloading of hydro power plant. Finally, simulations provide optimal values of control parameters, stability boundaries and results easily applicable to real hydro power plants. (author)

Moving grids for magnetic reconnection via Newton-Krylov methods

KAUST Repository

Yuan, Xuefei; Jardin, Stephen C.; Keyes, David E.

2011-01-01

This paper presents a set of computationally efficient, adaptive grids for magnetic reconnection phenomenon where the current density can develop large gradients in the reconnection region. Four-field extended MagnetoHydroDynamics (MHD) equations

Magneto-optical detection of the relaxation dynamics of alloy nanoparticles with a high-stability magnetic circular dichroism setup

Energy Technology Data Exchange (ETDEWEB)

Cavigli, L. [L.E.N.S. University of Florence, via N. Carrara 1, I-50019 Sesto F.no (Italy); INSTM Department of Chemistry, University of Florence, via della Lastruccia 5, I-50019 Sesto F.no (Italy); Julian Fernandez, C. de [Department of Physics, University of Padua, via Marzolo 8, I-35131 Padova (Italy); Gatteschi, D. [INSTM Department of Chemistry, University of Florence, via della Lastruccia 5, I-50019 Sesto F.no (Italy); Gurioli, M. [L.E.N.S. University of Florence, via N. Carrara 1, I-50019 Sesto F.no (Italy); Sangregorio, C. [INSTM Department of Chemistry, University of Florence, via della Lastruccia 5, I-50019 Sesto F.no (Italy)]. E-mail: claudio.sangregorio@unifi.it; Mattei, G. [Department of Physics, University of Padua, via Marzolo 8, I-35131 Padova (Italy); Mazzoldi, P. [Department of Physics, University of Padua, via Marzolo 8, I-35131 Padova (Italy); Bogani, L. [L.E.N.S. University of Florence, via N. Carrara 1, I-50019 Sesto F.no (Italy); INSTM Department of Chemistry, University of Florence, via della Lastruccia 5, I-50019 Sesto F.no (Italy)

2007-09-15

We present a versatile high-stability and high-sensitivity magneto-optical setup that allows transmission and reflection measurements at high fields and low temperatures. We apply the technique to measure the decay in time of the magnetization of highly monodisperse 3.3nm Co{sub 33}Ni{sub 67} alloy nanoparticles embedded in a silica host. We demonstrate the possibility of observing the dynamics of the magnetization over a macroscopic timescale in dilute samples, where other techniques are unavailable.

Magneto-optical detection of the relaxation dynamics of alloy nanoparticles with a high-stability magnetic circular dichroism setup

International Nuclear Information System (INIS)

Cavigli, L.; Julian Fernandez, C. de; Gatteschi, D.; Gurioli, M.; Sangregorio, C.; Mattei, G.; Mazzoldi, P.; Bogani, L.

2007-01-01

We present a versatile high-stability and high-sensitivity magneto-optical setup that allows transmission and reflection measurements at high fields and low temperatures. We apply the technique to measure the decay in time of the magnetization of highly monodisperse 3.3nm Co 33 Ni 67 alloy nanoparticles embedded in a silica host. We demonstrate the possibility of observing the dynamics of the magnetization over a macroscopic timescale in dilute samples, where other techniques are unavailable

Magneto-optical detection of the relaxation dynamics of alloy nanoparticles with a high-stability magnetic circular dichroism setup

Science.gov (United States)

Cavigli, L.; de Julián Fernández, C.; Gatteschi, D.; Gurioli, M.; Sangregorio, C.; Mattei, G.; Mazzoldi, P.; Bogani, L.

2007-09-01

We present a versatile high-stability and high-sensitivity magneto-optical setup that allows transmission and reflection measurements at high fields and low temperatures. We apply the technique to measure the decay in time of the magnetization of highly monodisperse 3.3 nm Co33Ni67 alloy nanoparticles embedded in a silica host. We demonstrate the possibility of observing the dynamics of the magnetization over a macroscopic timescale in dilute samples, where other techniques are unavailable.

The use of hydro-dynamic models in the practice-oriented education of engineering students

Science.gov (United States)

Sziebert, J.; Zellei, L.; Tamás, E. A.

2009-04-01

Management tasks related to open channel flows became rather comprehensive and multi-disciplinary, particularly with the predominancy of nature management aspects. The water regime of our rivers has proven to reach extremities more and more frequently in the past decades. In order to develop and analyse alternative solutions and to handle and resolve conflicts of interests, we apply 1D hydro-dynamic models in education for the explanation of processes and to improve practical skills of our students.

Enhancement of the transverse magneto-optical Kerr effect via resonant tunneling in trilayers containing magneto-optical metals

Energy Technology Data Exchange (ETDEWEB)

Girón-Sedas, J. A. [Departamento de Física, Universidad del Valle, AA 25360, Cali (Colombia); Centro de Investigación e Innovación en Bioinformática y Fotónica - CIBioFI, AA 25360 Cali (Colombia); Mejía-Salazar, J. R., E-mail: jrmejia3146@gmail.com [Instituto de Física de São Carlos, Universidade de São Paulo, CP 369, 13560-970 São Carlos, SP (Brazil); Moncada-Villa, E.; Porras-Montenegro, N. [Departamento de Física, Universidad del Valle, AA 25360, Cali (Colombia)

2016-07-18

We propose a way to enhance the transverse magneto-optical Kerr effect, by the excitation of resonant tunneling modes, in subwavelength trilayer structures featuring a dielectric slab sandwiched between two magneto-optical metallic layers. Depending on the magneto-optical layer widths, the proposed system may exhibit an extraordinary transverse magneto-optical Kerr effect, which makes it very attractive for the design and engineering of thin-film magneto-optical-based devices for future photonic circuits or fiber optical-communication systems.

Novel design of a self powered and self sensing magneto-rheological damper

International Nuclear Information System (INIS)

Ferdaus, Mohammad Meftahul; Rashid, M M; Bhuiyan, M M I; Muthalif, Asan Gani Bin Abdul; Hasan, M R

2013-01-01

Magneto-rheological (MR) dampers are semi-active control devices and use MR fluids. Magneto-rheological dampers have successful applications in mechatronics engineering, civil engineering and numerous areas of engineering. At present, traditional MR damper systems, require a isolated power supply and dynamic sensor. This paper presents the achievability and accuracy of a self- powered and self-sensing magneto-rheological damper using harvested energy from the vibration and shock environment in which it is deployed and another important part of this paper is the increased yield stress of the Magneto rheological Fluids. Magneto rheological fluids using replacement of glass beads for Magnetic Particles to surge yield stress is implemented here. Clearly this shows better result on yield stress, viscosity, and settling rate. Also permanent magnet generator (PMG) is designed and attached to a MR damper. For evaluating the self-powered MR damper's vibration mitigating capacity, an Engine Mount System using the MR damper is simulated. The ideal stiffness of the PMG for the Engine Mount System (EMS) is calculated by numerical study. The vibration mitigating performance of the EMS employing the self-powered and self sensing MR damper is theoretically calculated and evaluated in the frequency domain

Novel design of a self powered and self sensing magneto-rheological damper

Science.gov (United States)

Meftahul Ferdaus, Mohammad; Rashid, M. M.; Bhuiyan, M. M. I.; Muthalif, Asan Gani Bin Abdul; Hasan, M. R.

2013-12-01

Magneto-rheological (MR) dampers are semi-active control devices and use MR fluids. Magneto-rheological dampers have successful applications in mechatronics engineering, civil engineering and numerous areas of engineering. At present, traditional MR damper systems, require a isolated power supply and dynamic sensor. This paper presents the achievability and accuracy of a self- powered and self-sensing magneto-rheological damper using harvested energy from the vibration and shock environment in which it is deployed and another important part of this paper is the increased yield stress of the Magneto rheological Fluids. Magneto rheological fluids using replacement of glass beads for Magnetic Particles to surge yield stress is implemented here. Clearly this shows better result on yield stress, viscosity, and settling rate. Also permanent magnet generator (PMG) is designed and attached to a MR damper. For evaluating the self-powered MR damper's vibration mitigating capacity, an Engine Mount System using the MR damper is simulated. The ideal stiffness of the PMG for the Engine Mount System (EMS) is calculated by numerical study. The vibration mitigating performance of the EMS employing the self-powered & self sensing MR damper is theoretically calculated and evaluated in the frequency domain.

Magneto-Rheological Damper - An Experimental Study

OpenAIRE

Lozoya-Santos , Jorge De-Jesus; Morales-Menéndez , Rubén; Ramirez-Mendoza , Ricardo; Tudon-Martınez , Juan ,; Sename , Olivier; Dugard , Luc

2012-01-01

International audience; A Magneto-Rheological (MR) damper is evaluated under exhaustive experimental scenarios, generating a complete database. The obtained database includes classical tests and new proposals emphasizing the frequency contents. It also includes the impact of the electric current fluctuations. The variety of the performed experiments allows to study the MR damper force dynamics. A brief description of the damper behavior and a categorization of experiments based on driving con...

Coercivity of magneto-optical media by spin dynamics

International Nuclear Information System (INIS)

Suits, J.C.

1990-01-01

Spin dynamics computer simulations have been carried out to study the effect of pinning on domain-wall motion in TbFeCo-like media. These calculations were done on a 30x30x1 mesh, where the spin direction at each lattice site was calculated with the Landau--Lifshitz--Gilbert equation. The simulations were made in an IBM 3090 mainframe--personal computer environment where the result of the calculation is a movie that runs at three frames/second on an AT and shows graphically the domain-wall--defect interaction. The domain wall is caused to move in an external field toward a defect, and the maximum field that pins the domain wall was observed. The defects have finite length and zero magnetization, which correspond to voids or nonmagnetic second phase in the media. The simulation shows that small defects on the order of 100 A in size can pin walls with pinning strength appropriate to the coercivity of magneto-optical media, i.e., local coercivities in the range 1--10 kOe. For sufficiently high fields a single wall may break up into two separate sections at the defect, and then join together beyond the defect to become a single wall again. For rectangular defects, the coercivity depends strongly and nearly linearly on defect length (parallel to the domain-wall surface) and only weakly on defect width for widths greater than about 50 A (perpendicular to the wall surface)

A simulated plasma disruption experiment using a magneto-plasma-dynamic arcjet

International Nuclear Information System (INIS)

Madarame, H.; Sukegawa, T.; Okamoto, K.

1991-01-01

If a melt layer is expelled by a strong electromagnetic force from some places during a plasma disruption, the wall thickness is reduced there remarkably. Although this phenomenon is considered as a very important issue, it has not been studied so far because of its difficulty and complexity. In this study, the phenomenon was simulated using a magneto-plasma-dynamic (MPD) arcjet. The MPD arcjet was used as both a heat source and an electric current source. The current flowed radially in a stainless steel test piece installed in a transverse magnetic field. The circumferential electromagnetic force generated a swirl flow in the melt layer, causing a centrifugal force, which thinned the central part of the round region and formed a circular embankment on the fringe. A numerical code was developed which could calculate the melting, the evaporation and the melt layer movement by the centrifugal force and the beam pressure. The calculational results on the melting depth and the thickness reduction in the central part were compared with experiment. (orig.)

Stochastic dynamic programming optimization of BC Hydro's system under market and hydrologic uncertainties

International Nuclear Information System (INIS)

Druce, D.

2004-01-01

BC Hydro's installed generation capacity as of March 31, 2003 was 11,103 MW, of which 90 per cent was hydro power, 9 per cent was gas-fired and 1 per cent was non-integrated. The hydroelectric plants belong to one of three groups, the Peace River, Columbia River or small hydro which includes small to moderate sized-plants. Small hydro is controlled by hydrologic regime and storage limitations rather than by system requirements. The installed capacity for the 4 plants on the Columbia River totals 4,722 MW. The installed capacity at the 2 plants on the Peace River totals 3,424 MW. Both watersheds are subject to interior climate conditions with significant inflows from snowmelt and rainfall runoff. This presentation addressed the issue of mid-term hydro scheduling and its impact on markets. For the past 15 years, BC Hydro has used the marginal cost model for electricity trade and for operations planning. The model considers system loads and resources, and maximizes the expected net revenue over a planning horizon of 6 years. A marginal value of water stored in the Williston Reservoir has been established using the marginal cost model. The affect of weather, natural gas prices and water supply on hydro generation was also discussed. It was noted that information on spot market electricity prices has significantly improved since the electric power industry was deregulated in 1996. tabs., figs

Dynamic hydro-climatic networks in pristine and regulated rivers

Science.gov (United States)

Botter, G.; Basso, S.; Lazzaro, G.; Doulatyari, B.; Biswal, B.; Schirmer, M.; Rinaldo, A.

2014-12-01

Flow patterns observed at-a-station are the dynamical byproduct of a cascade of processes involving different compartments of the hydro-climatic network (e.g., climate, rainfall, soil, vegetation) that regulates the transformation of rainfall into streamflows. In complex branching rivers, flow regimes result from the heterogeneous arrangement around the stream network of multiple hydrologic cascades that simultaneously occur within distinct contributing areas. As such, flow regimes are seen as the integrated output of a complex "network of networks", which can be properly characterized by its degree of temporal variability and spatial heterogeneity. Hydrologic networks that generate river flow regimes are dynamic in nature. In pristine rivers, the time-variance naturally emerges at multiple timescales from climate variability (namely, seasonality and inter-annual fluctuations), implying that the magnitude (and the features) of the water flow between two nodes may be highly variable across different seasons and years. Conversely, the spatial distribution of river flow regimes within pristine rivers involves scale-dependent transport features, as well as regional climatic and soil use gradients, which in small and meso-scale catchments (A guarantee quite uniform flow regimes and high spatial correlations. Human-impacted rivers, instead, constitute hybrid networks where observed spatio-temporal patterns are dominated by anthropogenic shifts, such as landscape alterations and river regulation. In regulated rivers, the magnitude and the features of water flows from node to node may change significantly through time due to damming and withdrawals. However, regulation may impact river regimes in a spatially heterogeneous manner (e.g. in localized river reaches), with a significant decrease of spatial correlations and network connectivity. Provided that the spatial and temporal dynamics of flow regimes in complex rivers may strongly impact important biotic processes

Advanced magneto-optical microscopy: Imaging from picoseconds to centimeters - imaging spin waves and temperature distributions (invited

Directory of Open Access Journals (Sweden)

Necdet Onur Urs

2016-05-01

Full Text Available Recent developments in the observation of magnetic domains and domain walls by wide-field optical microscopy based on the magneto-optical Kerr, Faraday, Voigt, and Gradient effect are reviewed. Emphasis is given to the existence of higher order magneto-optical effects for advanced magnetic imaging. Fundamental concepts and advances in methodology are discussed that allow for imaging of magnetic domains on various length and time scales. Time-resolved imaging of electric field induced domain wall rotation is shown. Visualization of magnetization dynamics down to picosecond temporal resolution for the imaging of spin-waves and magneto-optical multi-effect domain imaging techniques for obtaining vectorial information are demonstrated. Beyond conventional domain imaging, the use of a magneto-optical indicator technique for local temperature sensing is shown.

Sub-nanosecond time-resolved near-field scanning magneto-optical microscope.

Science.gov (United States)

Rudge, J; Xu, H; Kolthammer, J; Hong, Y K; Choi, B C

2015-02-01

We report on the development of a new magnetic microscope, time-resolved near-field scanning magneto-optical microscope, which combines a near-field scanning optical microscope and magneto-optical contrast. By taking advantage of the high temporal resolution of time-resolved Kerr microscope and the sub-wavelength spatial resolution of a near-field microscope, we achieved a temporal resolution of ∼50 ps and a spatial resolution of microscope, the magnetic field pulse induced gyrotropic vortex dynamics occurring in 1 μm diameter, 20 nm thick CoFeB circular disks has been investigated. The microscope provides sub-wavelength resolution magnetic images of the gyrotropic motion of the vortex core at a resonance frequency of ∼240 MHz.

Regime of aggregate structures and magneto-rheological characteristics of a magnetic rod-like particle suspension: Monte Carlo and Brownian dynamics simulations

Energy Technology Data Exchange (ETDEWEB)

Okada, Kazuya [School of Akita Prefectural University, Yurihonjo (Japan); Satoh, Akira, E-mail: asatoh@akita-pu.ac.jp [Department of Machine Intelligence and System Engineering, Akita Prefectural University, Yurihonjo (Japan)

2017-09-01

Highlights: • Monte Carlo simulations have been employed for the aggregate structures. • Brownian dynamics simulations have been employed for the magneto-rheology. • Even a weak shear flow induces a significant regime change in the aggregates. • A strong external magnetic field drastically changes the aggregates. • The dependence of the viscosity on these factors is governed in a complex manner. - Abstract: In the present study, we address a suspension composed ferromagnetic rod-like particles to elucidate a regime change in the aggregate structures and the magneto-rheological characteristics. Monte Carlo simulations have been employed for investigating the aggregate structures in thermodynamic equilibrium, and Brownian dynamics simulations for magneto-rheological features in a simple shear flow. The main results obtained here are summarized as follows. For the case of thermodynamic equilibrium, the rod-like particles aggregate to form thick chain-like clusters and the neighboring clusters incline in opposite directions. If the external magnetic field is increased, the thick chain-like clusters in the magnetic field direction grow thicker by adsorbing the neighboring clusters that incline in the opposite direction. Hence, a significant phase change in the particle aggregates is not induced by an increase in the magnetic field strength. For the case of a simple shear flow, even a weak shear flow induces a significant regime change from the thick chain-like clusters of thermodynamic equilibrium into wall-like aggregates composed of short raft-like clusters. A strong external magnetic field drastically changes these aggregates into wall-like aggregates composed of thick chain-like clusters rather than the short raft-like clusters. The internal structure of these aggregates is not strongly influenced by a shear flow, and the formation of the short raft-like clusters is maintained inside the aggregates. The main contribution to the net viscosity is the

Magneto-plasmonic nanoantennas: Basics and applications

Directory of Open Access Journals (Sweden)

Ivan S. Maksymov

2016-11-01

Full Text Available Plasmonic nanoantennas are a hot and rapidly expanding research field. Here we overview basic operating principles and applications of novel magneto-plasmonic nanoantennas, which are made of ferromagnetic metals and driven not only by light, but also by external magnetic fields. We demonstrate that magneto-plasmonic nanoantennas enhance the magneto-optical effects, which introduces additional degrees of freedom in the control of light at the nano-scale. This property is used in conceptually new devices such as magneto-plasmonic rulers, ultra-sensitive biosensors, one-way subwavelength waveguides and extraordinary optical transmission structures, as well as in novel biomedical imaging modalities. We also point out that in certain cases ‘non-optical’ ferromagnetic nanostructures may operate as magneto-plasmonic nanoantennas. This undesigned extra functionality capitalises on established optical characterisation techniques of magnetic nanomaterials and it may be useful for the integration of nanophotonics and nanomagnetism on a single chip.

An Evaluation of Magneto Rheological Dampers for Controlling Gun Recoil Dynamics

Directory of Open Access Journals (Sweden)

Mehdi Ahmadian

2001-01-01

Full Text Available The application of magneto rheological dampers for controlling recoil dynamics is examined, using a recoil demonstrator that includes a single-shot 50 caliber BMG rifle action and a MR damper. The demonstrator is selected such that it can adequately represent the velocities that commonly occur in weapons with a recoil system, and can be used for collecting data for analyzing the effects of MR dampers on recoil dynamics. The MR damper is designed so that it can work effectively at the large velocities commonly occurring in gun recoil, and also be easily adjusted to reasonably optimize the damper performance for the recoil demonstrator. The test results show that it is indeed possible to design and use MR dampers for recoil applications, which subject the damper to relative velocities far larger than the applications that such dampers have commonly been used for (i.e., vehicle applications. Further, the results indicate that the recoil force increases and the recoil stroke decreases nonlinearly with an increase in the damping force. Also of significance is the fact that the adjustability of MR dampers can be used in a closed-loop system such that the large recoil forces that commonly occur upon firing the gun are avoided and, simultaneously, the recoil stroke is reduced. This study points to the need for several areas of research including establishing the performance capabilities for MR dampers for gun recoil applications in an exact manner, and the potential use of such dampers for a fire out of battery recoil system.

Sensor Applications of Soft Magnetic Materials Based on Magneto-Impedance, Magneto-Elastic Resonance and Magneto-Electricity

Directory of Open Access Journals (Sweden)

Alfredo García-Arribas

2014-04-01

Full Text Available The outstanding properties of selected soft magnetic materials make them successful candidates for building high performance sensors. In this paper we present our recent work regarding different sensing technologies based on the coupling of the magnetic properties of soft magnetic materials with their electric or elastic properties. In first place we report the influence on the magneto-impedance response of the thickness of Permalloy films in multilayer-sandwiched structures. An impedance change of 270% was found in the best conditions upon the application of magnetic field, with a low field sensitivity of 140%/Oe. Second, the magneto-elastic resonance of amorphous ribbons is used to demonstrate the possibility of sensitively measuring the viscosity of fluids, aimed to develop an on-line and real-time sensor capable of assessing the state of degradation of lubricant oils in machinery. A novel analysis method is shown to sensitively reveal the changes of the damping parameter of the magnetoelastic oscillations at the resonance as a function of the oil viscosity. Finally, the properties and performance of magneto-electric laminated composites of amorphous magnetic ribbons and piezoelectric polymer films are investigated, demonstrating magnetic field detection capabilities below 2.7 nT.

Comparison between dynamic programming and genetic algorithm for hydro unit economic load dispatch

Directory of Open Access Journals (Sweden)

Bin Xu

2014-10-01

Full Text Available The hydro unit economic load dispatch (ELD is of great importance in energy conservation and emission reduction. Dynamic programming (DP and genetic algorithm (GA are two representative algorithms for solving ELD problems. The goal of this study was to examine the performance of DP and GA while they were applied to ELD. We established numerical experiments to conduct performance comparisons between DP and GA with two given schemes. The schemes included comparing the CPU time of the algorithms when they had the same solution quality, and comparing the solution quality when they had the same CPU time. The numerical experiments were applied to the Three Gorges Reservoir in China, which is equipped with 26 hydro generation units. We found the relation between the performance of algorithms and the number of units through experiments. Results show that GA is adept at searching for optimal solutions in low-dimensional cases. In some cases, such as with a number of units of less than 10, GA's performance is superior to that of a coarse-grid DP. However, GA loses its superiority in high-dimensional cases. DP is powerful in obtaining stable and high-quality solutions. Its performance can be maintained even while searching over a large solution space. Nevertheless, due to its exhaustive enumerating nature, it costs excess time in low-dimensional cases.

An experimental investigation into nonlinear dynamics of a magneto-rheological elastomer sandwich beam

International Nuclear Information System (INIS)

Yildirim, Tanju; Ghayesh, Mergen H; Li, Weihua; Alici, Gursel

2016-01-01

An experimental investigation has been carried out on the nonlinear dynamics of a clamped–clamped Magneto-Rheological Elastomer (MRE) sandwich beam with a point mass when subjected to a point excitation. Three sets of experiments have been conducted namely for (i) an aluminium beam, (ii) a MRE sandwich beam in the absence of a magnetic field and (iii) a MRE sandwich beam in the presence of a magnetic field. An electrodynamic shaker was used to excite each system and the corresponding displacement of the point mass was measured: for the third experiment (iii), an array of magnets has been placed at various distances away from the centre of the point mass to investigate the effect of changing stiffness and damping properties on the nonlinear dynamical behaviour. An interesting feature for the third group is the beam point mass displacement was no longer symmetric as the stiffness and damping of the system are increased when moving towards the magnets. Both the first and second groups exhibited distinct nonlinear behaviour; however, for the third group this work shows that for a low magnetic field the sandwich beam exhibits two distinct resonance peaks, one occurring above and the other below the fundamental natural frequency of the transverse motion, with the right one larger. For a larger magnetic field, these peaks even out until the magnetic force was large enough that the hardening-type nonlinear behaviour changes to a softening-type; a significant qualitative change in the nonlinear dynamical behaviour of the system, due to the presence of the magnetic field, was observed. (paper)

Analysis of Magneto-Piezoelastic Anisotropic Materials

Directory of Open Access Journals (Sweden)

Alexander L. Kalamkarov

2015-05-01

Full Text Available The paper is concerned with the analysis of magneto-piezoelastic anistropic materials. Analytical modeling of magneto-piezoelastic materials is essential for the design and applications in the smart composite structures incorporating them as actuating and sensing constituents. It is shown that Green’s function method is applicable to time harmonic magneto-elastic-piezoelectricity problems using the boundary integral technique, and the exact analytical solutions are obtained. As an application, a two-dimensional static plane-strain problem is considered to investigate the effect of magnetic field on piezoelectric materials. The closed-form analytical solutions are obtained for a number of boundary conditions for all components of the magneto-piezoelectric field. As a special case, numerical results are presented for two-dimensional static magneto-electroelastic field of a piezoelectric solid subjected to a concentrated line load and an electric charge. The numerical solutions are obtained for three different piezoelectric materials and they demonstrate a substantial dependence of the stress and electric field distribution on the constitutive properties and magnetic flux.

Determination and modeling of the influence of the fluid-dynamics in hydro-treating bench scale plants

Energy Technology Data Exchange (ETDEWEB)

Burkhardt, T.

1999-09-16

At an industrial scale, the hydro-treating of oil fractions is carried out in multiphase fixed bed reactors. The oil and hydrogen cross the catalyst bed, usually in co-current downflow. Since the product specifications are steadily becoming more severe, the testing of new catalysts and of modified operating conditions in pilot plants becomes increasingly important. Although these pilot plants are frequently by a factor of 100 000 smaller than the industrial units, they still have to allow the up-scaling to industrial units. In the literature relatively low conversion degrees in pilot plants are frequently reported, especially in downflow. The significantly lower fluid velocities in pilot plants seem to be responsible for such differences, as the influence of fluid-dynamic non-idealities and of the extra-particle mass transfer phenomena increases with a decrease of the fluid velocities. In the present work, the influence of important fluid-dynamic non-idealities on the hydro-treating of gas oil fractions in pilot plants was examined. This was done on the one hand in experiments with different pilot plants and on the other hand by simulations with an especially developed multiphase model. The phenomena were considered as well in an isolated manner. In order to examine any interactions with the chemical reactions, they were also studied in a reactive system. This methodology was applied to the phenomena, 'axial dispersion'and 'gas-liquid mass transfer'. (author)

Stochastic dynamic programming optimization of BC Hydro's system under market and hydrologic uncertainties

Energy Technology Data Exchange (ETDEWEB)

Druce, D. [British Columbia Hydro, Vancouver, BC (Canada)

2004-07-01

BC Hydro's installed generation capacity as of March 31, 2003 was 11,103 MW, of which 90 per cent was hydro power, 9 per cent was gas-fired and 1 per cent was non-integrated. The hydroelectric plants belong to one of three groups, the Peace River, Columbia River or small hydro which includes small to moderate sized-plants. Small hydro is controlled by hydrologic regime and storage limitations rather than by system requirements. The installed capacity for the 4 plants on the Columbia River totals 4,722 MW. The installed capacity at the 2 plants on the Peace River totals 3,424 MW. Both watersheds are subject to interior climate conditions with significant inflows from snowmelt and rainfall runoff. This presentation addressed the issue of mid-term hydro scheduling and its impact on markets. For the past 15 years, BC Hydro has used the marginal cost model for electricity trade and for operations planning. The model considers system loads and resources, and maximizes the expected net revenue over a planning horizon of 6 years. A marginal value of water stored in the Williston Reservoir has been established using the marginal cost model. The affect of weather, natural gas prices and water supply on hydro generation was also discussed. It was noted that information on spot market electricity prices has significantly improved since the electric power industry was deregulated in 1996. tabs., figs.

New Magneto-Inductive DC Magnetometer for Space Missions

Science.gov (United States)

Moldwin, M.; Bronner, B.; Regoli, L.; Thoma, J.; Shen, A.; Jenkins, G.; Cutler, J.

2017-12-01

A new magneto-inductive DC magnetometer is being developed at the University of Michigan that provides fluxgate quality measurements in a low mass, volume, power and cost package. The magnetometer enables constellation-class missions not only due to its low-resource requirements, but also its potential for commercial integrated circuit fabrication. The magneto-inductive operating principle is based on a simple resistance-inductor (RL) circuit and involves measurement of the time it takes to charge and discharge the inductor between an upper and lower threshold by means of a Schmitt trigger oscillator. This time is proportional to the inductance that in turn is proportional to the field strength. We have modeled the operating principle in the circuit simulator SPICE and have built a proto-type using modified commercial sensors. The performance specifications include a dynamic range over the full-Earth's field, sampling rates up to 80 Hz, sensor and electronics mass of about 30 g, circuit board and sensor housing volume of magnetometer.

Introducing Magneto-Optical Functions into Soft Materials

Science.gov (United States)

2017-05-03

including organic and bio materials by using magnetic nanomaterials. This final report includes the successful developments of magneto-optical... successful developments of magneto-optical properties in both organic and bio magnetic nanocomposites during the project period of three years...proteins on the photoluminescence of nanodiamond. J. Appl . Phys. 2011, 109 (3), 034704. 7, Xu, H.; Hung, C.E.; Cheng, C.L.; Hu, B., Magneto-electric

Relativistic conformal magneto-hydrodynamics from holography

International Nuclear Information System (INIS)

Buchbinder, Evgeny I.; Buchel, Alex

2009-01-01

We use the AdS/CFT correspondence to study first-order relativistic viscous magneto-hydrodynamics of (2+1)-dimensional conformal magnetic fluids. It is shown that the first order magneto-hydrodynamics constructed following Landau and Lifshitz from the positivity of the entropy production is inconsistent. We propose additional contributions to the entropy motivated dissipative current and, correspondingly, new dissipative transport coefficients. We use the strongly coupled M2-brane plasma in external magnetic field to show that the new magneto-hydrodynamics leads to self-consistent results in the shear and sound wave channels.

Studying the cumulative environmental effects of Hydro-Quebec's installations plan

International Nuclear Information System (INIS)

Dubeau, D.

1992-01-01

The study of the cumulative environmental effects that have been integrated with technical and economic analyses include mercury, land use in the region (territory), natural landscapes, cultural heritages, forest dynamics, regional economies and ways of life. Requests and petitions from the public about Hydro-Quebec projects fall into four categories: welfare of communities, impact on the land, environmental responsibility and preservation of plant and animal species. The cooperation of all concerned is necessary for Hydro-Quebec's developments. (author)

Cryogenically enhanced magneto-Archimedes levitation

Energy Technology Data Exchange (ETDEWEB)

Catherall, A T; Lopez-Alcaraz, P; Benedict, K A; King, P J; Eaves, L [School of Physics and Astronomy, University of Nottingham, Nottingham NG7 2RD (United Kingdom)

2005-05-01

The application of both a strong magnetic field and magnetic field gradient to a diamagnetic body can produce a vertical force which is sufficient to counteract its weight due to gravity. By immersing the body in a paramagnetic fluid, an additional adjustable magneto-buoyancy force is generated which enhances the levitation effect. Here we show that cryogenic oxygen and oxygen-nitrogen mixtures in both gaseous and liquid form provide sufficient buoyancy to permit the levitation and flotation of a wide range of materials. These fluids may provide an alternative to synthetic ferrofluids for the separation of minerals. We also report the dynamics of corrugation instabilities on the surface of magnetized liquid oxygen.

Cryogenically enhanced magneto-Archimedes levitation

International Nuclear Information System (INIS)

Catherall, A T; Lopez-Alcaraz, P; Benedict, K A; King, P J; Eaves, L

2005-01-01

The application of both a strong magnetic field and magnetic field gradient to a diamagnetic body can produce a vertical force which is sufficient to counteract its weight due to gravity. By immersing the body in a paramagnetic fluid, an additional adjustable magneto-buoyancy force is generated which enhances the levitation effect. Here we show that cryogenic oxygen and oxygen-nitrogen mixtures in both gaseous and liquid form provide sufficient buoyancy to permit the levitation and flotation of a wide range of materials. These fluids may provide an alternative to synthetic ferrofluids for the separation of minerals. We also report the dynamics of corrugation instabilities on the surface of magnetized liquid oxygen

Hydro under shock

International Nuclear Information System (INIS)

Maffezzini, I.; Pineault, E.; Poirier, M.

1997-01-01

A discussion of the potential privatisation of Hydro-Quebec, and of the motivation to do so, was presented. The creation of Hydro-Quebec resulted from the nationalization in 1963 of all major electricity producers in the province of Quebec. Since its inception, Hydro-Quebec has gone through many episodes of restructuring but none more far reaching in extent, or in consequences, than the present one. The current deregulation of the electrical industry in Quebec, and the potential commercialization of Hydro-Quebec is considered to be a natural and inevitable result of the current global trend towards competition in the power industry and the demand for greater consumer choice. 1 tab

Hydro-climatology

DEFF Research Database (Denmark)

The hydro-climatological approach of this volume illustrates the scientific and practical value of considering hydrological phenomena and processes in a climate context to improve understanding of controls, process interaction, and past and future variability/change. Contributions deal with under......The hydro-climatological approach of this volume illustrates the scientific and practical value of considering hydrological phenomena and processes in a climate context to improve understanding of controls, process interaction, and past and future variability/change. Contributions deal...... considered. The interdisciplinary approach reveals information and perspective that go beyond the study of cli ate and hydro gy alone...

Magneto-Hydro-Dynamics Liquid Wheel Actuator for Spacecraft Attitude Control

Science.gov (United States)

2017-01-26

configuration: this configuration switches the first configuration considering an electric current along the axial direction z and a magnetic field along the...u = 0, and considering the boundaries electrically insulating , the induced magnetic field vanishes at the boundaries, b = 0. If the boundaries is...has been developed on the basis of the MHD set of equations under the hypothesis of low Magnetic Reynolds. The model solves numerically the time

Magneto-optical extinction trend inversion in ferrofluids

Energy Technology Data Exchange (ETDEWEB)

Shulyma, S.I., E-mail: kiw_88@mail.ru; Tanygin, B.M., E-mail: b.m.tanygin@gmail.com; Kovalenko, V.F.; Petrychuk, M.V.

2016-10-15

Effects of pulse magnetic field on the optical transmission properties of thin ferrofluid (FF) layers were experimentally investigated. It was observed that, under an influence of an external uniform magnetic field, pulses applied to the samples surfaces in normal direction decrease the optical transmission with further returning it to its original state, even before the end of the field pulse. The dependencies of the observed effects on the magnetic pulse magnitude and the samples thickness were investigated. The experimental results are explained using FF columnar aggregates growth and lateral coalescence under influence of a magnetic field, leading to a light scattering type Rayleigh-to-Mie transition. Further evolution of this process comes to a geometrical optics scale and respective macroscopic observable opaque FF columnar aggregates emergence. These changes of optical transmission are non-monotonic during the magnetic field pulse duration with minimal value in the case of Mie scattering, which is known as a magneto-optical extinction trend inversion. The residual inversion was detected after the external magnetic field pulse falling edge. Using molecular dynamics simulation, we showed that a homogeneous external magnetic field is enough for the formation of columnar aggregates and their fusion. The results clarify the known Li theory (Li et al., 2004, 2007), implying an inhomogeneous field as a required prerequisite for the magneto-optical extinction trend inversion phenomenon. - Highlights: • Ferrofluid columnar aggregates have been observed in a homogeneous magnetic field. • Magneto-optical extinction trend inversion is related to the Mie light scattering. • Crucial role of columnar aggregates growth and lateral coalescence has been revealed. • Residual extinction trend inversion was observed after the field switch off.

Magneto-optical extinction trend inversion in ferrofluids

International Nuclear Information System (INIS)

Shulyma, S.I.; Tanygin, B.M.; Kovalenko, V.F.; Petrychuk, M.V.

2016-01-01

Effects of pulse magnetic field on the optical transmission properties of thin ferrofluid (FF) layers were experimentally investigated. It was observed that, under an influence of an external uniform magnetic field, pulses applied to the samples surfaces in normal direction decrease the optical transmission with further returning it to its original state, even before the end of the field pulse. The dependencies of the observed effects on the magnetic pulse magnitude and the samples thickness were investigated. The experimental results are explained using FF columnar aggregates growth and lateral coalescence under influence of a magnetic field, leading to a light scattering type Rayleigh-to-Mie transition. Further evolution of this process comes to a geometrical optics scale and respective macroscopic observable opaque FF columnar aggregates emergence. These changes of optical transmission are non-monotonic during the magnetic field pulse duration with minimal value in the case of Mie scattering, which is known as a magneto-optical extinction trend inversion. The residual inversion was detected after the external magnetic field pulse falling edge. Using molecular dynamics simulation, we showed that a homogeneous external magnetic field is enough for the formation of columnar aggregates and their fusion. The results clarify the known Li theory (Li et al., 2004, 2007), implying an inhomogeneous field as a required prerequisite for the magneto-optical extinction trend inversion phenomenon. - Highlights: • Ferrofluid columnar aggregates have been observed in a homogeneous magnetic field. • Magneto-optical extinction trend inversion is related to the Mie light scattering. • Crucial role of columnar aggregates growth and lateral coalescence has been revealed. • Residual extinction trend inversion was observed after the field switch off.

Ontario Hydro's nuclear program

International Nuclear Information System (INIS)

McCredie, J.

1984-01-01

This report briefly describes Ontario Hydro's nuclear program, examining the design and construction status, and the future from Ontario Hydro's perspective. Ontario Hydro relies heavily on nuclear power. Nuclear fuel was responsible for approximately 34% of Ontario Hydro's energy production in 1983. The nuclear proportion was supplied by twelve operating units located: NPD, Douglas Point, Pickering A and B. It is expected that by approximately 1992, 65% of the total energy needs will be generated through nuclear power

HydroSoft coil versus HydroCoil for endovascular aneurysm occlusion study: A single center experience

International Nuclear Information System (INIS)

Guo Xinbin; Fan Yimu; Zhang Jianning

2011-01-01

Background and purpose: The HydroCoil Embolic System (HES) was developed to reduce recurrences of aneurysms relative to platinum coils. But the HydroCoil Embolic System was characterized with many limitations. The manufacturer had recognized the challenge and recently a new design of hydrogel-coated coil-HydroSoft has become available in the market as the new generation HydroCoil. We reported our initial experience using HydroSoft coil versus HydroCoil in our center. Methods: 75 aneurysms embolized primarily using HydroSoft Coils from July 2008 to May 2009 were compared with 66 volume- and shape-matched aneurysms treated with HydroCoils from March 2006 to August 2008. Outcome measures included length and number of coils used, contrast volume, and length of hospital stay. During embolization, a stable framework was first established with bare coils, and hydrogel-coated coils were used subsequently to increase the packing density. Follow-up angiographic results 6 months after treatment were evaluated among some of the patients. Results: Successful coil embolization was achieved in all patients. There were no differences in average total coil length used per aneurysm. There were no differences in length of hospital stay and packing density. HydroSoft coils were more suitable using as the finishing or final coil. HydroSoft coil decreased the procedure-related retreated rates, and aneurysm packing was finished with soft, flexible HydroSoft coil and decreased the neck remnant rates. Follow-up angiography in HydroSoft-treated patients at 6 months revealed aneurysm stability without significant residual neck. Conclusions: HydroSoft coil allowed us to deploy coated coils with good packing density. A slight expansion of these coils at the neck can be expected to reduce neck remnant and potentially inhibit recurrence.

Magneto-optical light scattering from ferromagnetic surfaces

International Nuclear Information System (INIS)

Gonzalez, M.U.; Armelles, G.; Martinez Boubeta, C.; Cebollada, A.

2003-01-01

We have studied the optical and magneto-optical components of the light scattered by the surface of several Fe films with different morphologies. We present a method, based on the ratio between the optical and magneto-optical components of the scattered intensity, to discern the physical origin, either structural or magnetic corrugation, of the light scattered by these ferromagnetic surfaces. Surface versus bulk magnetic information can be separated by magneto-optical light scattering measurements, the scattered light being more sensitive to magnetization differences between surface and bulk than the reflected one

Magneto-optical non-reciprocal devices in silicon photonics

Directory of Open Access Journals (Sweden)

Yuya Shoji

2014-01-01

Full Text Available Silicon waveguide optical non-reciprocal devices based on the magneto-optical effect are reviewed. The non-reciprocal phase shift caused by the first-order magneto-optical effect is effective in realizing optical non-reciprocal devices in silicon waveguide platforms. In a silicon-on-insulator waveguide, the low refractive index of the buried oxide layer enhances the magneto-optical phase shift, which reduces the device footprints. A surface activated direct bonding technique was developed to integrate a magneto-optical garnet crystal on the silicon waveguides. A silicon waveguide optical isolator based on the magneto-optical phase shift was demonstrated with an optical isolation of 30 dB and insertion loss of 13 dB at a wavelength of 1548 nm. Furthermore, a four port optical circulator was demonstrated with maximum isolations of 15.3 and 9.3 dB in cross and bar ports, respectively, at a wavelength of 1531 nm.

Mathematical methods in electro-magneto-elasticity

CERN Document Server

Bardzokas, DI; Filshtinsky, LA

2007-01-01

The mechanics of Coupled Fields is a discipline at the edge of modern research connecting Continuum Mechanics with Solid State Physics. It integrates the Mechanics of Continuous Media, Heat Conductivity and the theory of Electromagnetism that are usually studied separately. For an accurate description of the influence of static and dynamic loadings, high temperatures and strong electromagnetic fields in elastic media and constructive installations, a new approach is required; an approach that has the potential to establish a synergism between the above mentioned fields. Throughout the book a vast number of problems are considered: two-dimensional problems of electro-magneto-elasticity as well as static and dynamical problems for piecewise homogenous compound piezoelectric plates weakened by cracks and openings. The boundary conditions, the constructive equations and the mathematical methods for their solution are thoroughly presented, so that the reader can get a clear quantitative and qualitative understandi...

76 FR 67175 - Riverbank Hydro No. 2 LLC, Lock Hydro Friends Fund XXXVI, Arkansas Electric Cooperative Corp...

Science.gov (United States)

2011-10-31

...; 14149-000] Riverbank Hydro No. 2 LLC, Lock Hydro Friends Fund XXXVI, Arkansas Electric Cooperative Corp... Lock Hydro Friends Fund XXXVI (Lock Hydro) and on April 11, 2011, Arkansas Electric Cooperative Corp... & Dam No. 3, as directed by the Corps. Applicant Contact: Mr. Wayne F. Krouse, Hydro Green Energy, 5090...

Hydro-energy

International Nuclear Information System (INIS)

Bacher, P.; Tardieu, B.

2005-01-01

The first part of this study concerns the different type of hydraulic works. The second part presents the big hydro-energy, its advantages and disadvantages, the industrial risks, the electric power transport network, the economy and the development perspectives. The third part presents the little hydro-energy, its advantages and disadvantages, the decentralized production and the development perspectives. (A.L.B.)

Rayleigh wave behavior in functionally graded magneto-electro-elastic material

Science.gov (United States)

Ezzin, Hamdi; Mkaoir, Mohamed; Amor, Morched Ben

2017-12-01

Piezoelectric-piezomagnetic functionally graded materials, with a gradual change of the mechanical and electromagnetic properties have greatly applying promises. Based on the ordinary differential equation and stiffness matrix methods, a dynamic solution is presented for the propagation of the wave on a semi-infinite piezomagnetic substrate covered with a functionally graded piezoelectric material (FGPM) layer. The materials properties are assumed to vary in the direction of the thickness according to a known variation law. The phase and group velocity of the Rayleigh wave is numerically calculated for the magneto-electrically open and short cases, respectively. The effect of gradient coefficients on the phase velocity, group velocity, coupled magneto-electromechanical factor, on the stress fields, the magnetic potential and the mechanical displacement are discussed, respectively. Illustration is achieved on the hetero-structure PZT-5A/CoFe2O4; the obtained results are especially useful in the design of high-performance acoustic surface devices and accurately prediction of the Rayleigh wave propagation behavior.

Proceeding of the Sixth Nuclear and Particle Physics Conference (NUPPAC-2007)

International Nuclear Information System (INIS)

2008-11-01

The publication has been set up as proceedings of the Nuclear and Particle Physics conference, the conference contains of the following subjects: High Energy Physics; Nuclear Scattering and Reactions; Nuclear Structure and Spectroscopy; Nuclear and Reactor Physics; Relativistic and Quantum Physics; Plasma and magneto hydro Dynamics; Computation and Simulation and Radiation Measurement and Dosimetry. This conference consists of 642 pages., figs., tabs., refs

CREATE-NL+: A robust control-oriented free boundary dynamic plasma equilibrium solver

International Nuclear Information System (INIS)

Albanese, R.; Ambrosino, R.; Mattei, M.

2015-01-01

CREATE-NL+ is a FEM (Finite Elements Method) solver of the free boundary dynamic plasma equilibrium problem, i.e. the MHD (Magneto Hydro Dynamics) time evolution of 2D axisymmetric plasmas in toroidal nuclear fusion devices, including eddy currents in the passive structures, and feedback control laws for current, position and shape control. This is an improved version of the CREATE-NL code developed in 2002 which was validated on JET and used for the design of the XSC (eXtreme Shape Controller), and for simulation studies on many existing and future tokamaks. A significant improvement was the use of a robust numerical scheme for the calculation of the Jacobian matrix within the Newton based scheme for the solution of the FEM nonlinear algebraic equations. The improved capability of interfacing with other codes, and a general decrease of the computational burden for the simulation of long pulses with small time steps makes this code a flexible tool for the design and testing of magnetic control in a tokamak.

CREATE-NL+: A robust control-oriented free boundary dynamic plasma equilibrium solver

Energy Technology Data Exchange (ETDEWEB)

Albanese, R. [Ass. EURATOM/ENEA/CREATE, Universita’ di Napoli “Federico II”, Naples (Italy); Ambrosino, R. [Ass. EURATOM/ENEA/CREATE, Universita’ di Napoli “Parthenope”, Naples (Italy); Mattei, M., E-mail: massimiliano.mattei@unina2.it [Ass. EURATOM/ENEA/CREATE, Seconda Universita’ di Napoli, Naples (Italy)

2015-10-15

CREATE-NL+ is a FEM (Finite Elements Method) solver of the free boundary dynamic plasma equilibrium problem, i.e. the MHD (Magneto Hydro Dynamics) time evolution of 2D axisymmetric plasmas in toroidal nuclear fusion devices, including eddy currents in the passive structures, and feedback control laws for current, position and shape control. This is an improved version of the CREATE-NL code developed in 2002 which was validated on JET and used for the design of the XSC (eXtreme Shape Controller), and for simulation studies on many existing and future tokamaks. A significant improvement was the use of a robust numerical scheme for the calculation of the Jacobian matrix within the Newton based scheme for the solution of the FEM nonlinear algebraic equations. The improved capability of interfacing with other codes, and a general decrease of the computational burden for the simulation of long pulses with small time steps makes this code a flexible tool for the design and testing of magnetic control in a tokamak.

Smoothed Particle Hydro-dynamic Analysis of Improvement in Sludge Conveyance Efficiency of Screw Decanter Centrifuge

Energy Technology Data Exchange (ETDEWEB)

Park, Dae Woong [Korea Testing and Research Institute, Kwachun (Korea, Republic of)

2015-03-15

A centrifuge works on the principle that particles with different densities will separate at a rate proportional to the centrifugal force during high-speed rotation. Dense particles are quickly precipitated, and particles with relatively smaller densities are precipitated more slowly. A decanter-type centrifuge is used to remove, concentrate, and dehydrate sludge in a water treatment process. This is a core technology for measuring the sludge conveyance efficiency improvement. In this study, a smoothed particle hydro-dynamic analysis was performed for a decanter centrifuge used to convey sludge to evaluate the efficiency improvement. This analysis was applied to both the original centrifugal model and the design change model, which was a ball-plate rail model, to evaluate the sludge transfer efficiency.

Smoothed Particle Hydro-dynamic Analysis of Improvement in Sludge Conveyance Efficiency of Screw Decanter Centrifuge

International Nuclear Information System (INIS)

Park, Dae Woong

2015-01-01

A centrifuge works on the principle that particles with different densities will separate at a rate proportional to the centrifugal force during high-speed rotation. Dense particles are quickly precipitated, and particles with relatively smaller densities are precipitated more slowly. A decanter-type centrifuge is used to remove, concentrate, and dehydrate sludge in a water treatment process. This is a core technology for measuring the sludge conveyance efficiency improvement. In this study, a smoothed particle hydro-dynamic analysis was performed for a decanter centrifuge used to convey sludge to evaluate the efficiency improvement. This analysis was applied to both the original centrifugal model and the design change model, which was a ball-plate rail model, to evaluate the sludge transfer efficiency.

Frequency dependent magneto-transport in charge transfer Co(II) complex

Energy Technology Data Exchange (ETDEWEB)

Shaw, Bikash Kumar; Saha, Shyamal K., E-mail: cnssks@iacs.res.in

2014-09-01

A charge transfer chelated system containing ferromagnetic metal centers is the ideal system to investigate the magneto-transport and magneto-dielectric effects due to the presence of both electronic as well as magnetic properties and their coupling. Magneto-transport properties in materials are usually studied through dc charge transport under magnetic field. As frequency dependent conductivity is an essential tool to understand the nature of carrier wave, its spatial extension and their mutual interaction, in the present work, we have investigated frequency dependent magneto-transport along with magnetization behavior in [Co{sub 2}(II)-(5-(4-PhMe)-1,3,4-oxadiazole-H{sup +}-2-thiolate){sub 5}](OAc){sub 4} metal complex to elucidate the nature of above quantities and their response under magnetic field in the transport property. We have used the existing model for ac conduction incorporating the field dependence to explain the frequency dependent magneto-transport. It is seen that the frequency dependent magneto-transport could be well explained using the existing model for ac conduction. -Highlights: • Chelated Co(II) complex is synthesized for magneto-transport applications. • Frequency dependent magneto-transport and magnetization behavior are studied. • Nature of carrier wave, its spatial extension is investigated under magnetic field. • Existing model for ac conduction is used with magnetic field dependence.

Enhanced tunability of magneto-impedance and magneto-capacitance in annealed Metglas/PZT magnetoelectric composites

Science.gov (United States)

Leung, Chung Ming; Zhuang, Xin; Xu, Junran; Li, Jiefang; Zhang, Jitao; Srinivasan, G.; Viehland, D.

2018-05-01

This report is on a new class of magnetostatically tunable magneto-impedance and magneto-capacitance devices based on a composite of ferromagnetic Metglas and ferroelectric lead zirconate titanate (PZT). Layered magneto-electric (ME) composites with annealed Metglas and PZT were studied in a longitudinal in-plane magnetic field-transverse electric field (L-T) mode. It was found that the degree of tunability was dependent on the annealing temperature of Metglas. An impedance tunability (ΔZ/Z0) of ≥400% was obtained at the electromechanical resonance (EMR) frequency (fr) for a sample with Metglas layers annealed at Ta = 500oC. This tunability is a factor of two higher than for composites with Metglas annealed at 350oC. The tunability of the capacitance, (ΔC/C0), was found to be 290% and -135k% at resonance and antiresonance, respectively, for Ta = 500oC. These results provide clear evidence for improvement in static magnetic field tunability of impedance and capacitance of ME composites with the use of annealed Metglas and are of importance for their potential use in tunable electronic applications.

Ontario Hydro's DSP update

International Nuclear Information System (INIS)

Anon.

1992-01-01

Ontario Hydro's Demand/Supply Plan (DSP), the 25 year plan which was submitted in December 1989, is currently being reviewed by the Environmental Assessment Board (EAB). Since 1989 there have been several changes which have led Ontario Hydro to update the original Demand/Supply Plan. This information sheet gives a quick overview of what has changed and how Ontario Hydro is adapting to that change

Tunable magneto-conductance and magneto-electroluminescence in polymer light-emitting electrochemical planar devices

Energy Technology Data Exchange (ETDEWEB)

Geng, R.; Mayhew, N. T.; Nguyen, T. D., E-mail: ngtho@uga.edu [Department of Physics and Astronomy, University of Georgia, Athens, Georgia 30602 (United States)

2013-12-09

We report studies of magneto-conductance (MC) and magneto-electroluminescence (MEL) in polymer light-emitting electrochemical planar devices using “super-yellow” poly-(phenylene vinylene). We observed consistent negative MC while MEL becomes positive when electroluminescence quantum efficiency (ELQE) increases. At an optimal ELQE, the MC has a much narrower width than the MEL, indicating that the MC and MEL do not share a common origin. However, MC reverses and has the same width as MEL when exposed to a threshold laser power. We show that the e-h pair model can explain the positive MEL and MC while the negative MC can be explained by the bipolaron model.

Tunable magneto-conductance and magneto-electroluminescence in polymer light-emitting electrochemical planar devices

International Nuclear Information System (INIS)

Geng, R.; Mayhew, N. T.; Nguyen, T. D.

2013-01-01

We report studies of magneto-conductance (MC) and magneto-electroluminescence (MEL) in polymer light-emitting electrochemical planar devices using “super-yellow” poly-(phenylene vinylene). We observed consistent negative MC while MEL becomes positive when electroluminescence quantum efficiency (ELQE) increases. At an optimal ELQE, the MC has a much narrower width than the MEL, indicating that the MC and MEL do not share a common origin. However, MC reverses and has the same width as MEL when exposed to a threshold laser power. We show that the e-h pair model can explain the positive MEL and MC while the negative MC can be explained by the bipolaron model

78 FR 56224 - Hydro Nelson, Ltd.; Hydro-WM, LLC; Notice of Transfer of Exemption

Science.gov (United States)

2013-09-12

... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Project No. 3401-049] Hydro Nelson, Ltd.; Hydro-WM, LLC; Notice of Transfer of Exemption 1. By documentation filed July 8, 2013 and supplemented... Hydro-WM, LLC. The project is located on the Rockfish River in Nelson County, Virginia. The transfer of...

Bloch oscillations of quasispin polaritons in a magneto-optically controlled atomic ensemble

International Nuclear Information System (INIS)

Jiang, Chang; Lu, Jing; Zhou, Lan

2012-01-01

We consider the propagation of quantized polarized light in a magneto-optically-manipulated atomic ensemble with a tripod configuration. A polariton formalism is applied when the medium is subjected to a washboard magnetic field under electromagnetically-induced transparency. The dark-state polariton with multiple components is achieved. We analyze the quantum dynamics of the dark-state polariton using experimental data from the rubidium D1-line. It is found that one component propagates freely, however the wave packet trajectory of the other component performs Bloch oscillations. -- Highlights: ► We study the wave–particle dualism of quasiparticles in a magneto-optical medium. ► We generate a “spin”-component dark-state polariton. ► Magnetic fields lead to oscillation and free propagation of a dark-state polariton. ► Our approach shows the role of entanglement of degrees of freedom of photons.

Bloch oscillations of quasispin polaritons in a magneto-optically controlled atomic ensemble

Energy Technology Data Exchange (ETDEWEB)

Jiang, Chang [Key Laboratory of Low-Dimensional Quantum Structures and Quantum Control of Ministry of Education, and Department of Physics, Hunan Normal University, Changsha 410081 (China); Lu, Jing, E-mail: lujing@hunnu.edu.cn [Key Laboratory of Low-Dimensional Quantum Structures and Quantum Control of Ministry of Education, and Department of Physics, Hunan Normal University, Changsha 410081 (China); Zhou, Lan [Key Laboratory of Low-Dimensional Quantum Structures and Quantum Control of Ministry of Education, and Department of Physics, Hunan Normal University, Changsha 410081 (China)

2012-10-01

We consider the propagation of quantized polarized light in a magneto-optically-manipulated atomic ensemble with a tripod configuration. A polariton formalism is applied when the medium is subjected to a washboard magnetic field under electromagnetically-induced transparency. The dark-state polariton with multiple components is achieved. We analyze the quantum dynamics of the dark-state polariton using experimental data from the rubidium D1-line. It is found that one component propagates freely, however the wave packet trajectory of the other component performs Bloch oscillations. -- Highlights: ► We study the wave–particle dualism of quasiparticles in a magneto-optical medium. ► We generate a “spin”-component dark-state polariton. ► Magnetic fields lead to oscillation and free propagation of a dark-state polariton. ► Our approach shows the role of entanglement of degrees of freedom of photons.

Dynamic magneto-optical imaging of transport current redistribution and normal zone propagation in YBa2Cu3O7-δ coated conductor

International Nuclear Information System (INIS)

Song Honghai; Schwartz, Justin; Davidson, Michael W

2009-01-01

YBa 2 Cu 3 O 7-δ (YBCO) coated conductors carry high critical current density with the potential for low cost and thus have a broad range of potential applications. An unresolved issue that could inhibit implementation, however, is a lack of understanding of the current redistribution and normal zone propagation behavior in the event of a thermal disturbance (quench). In this work, we for the first time present the real-time, dynamic observation of magnetic field redistribution during a thermal disturbance via magneto-optical imaging with a high speed, high resolution CCD (charge coupled device) camera. The optical images are converted to a two-dimensional, time-dependent data set that is then analyzed quantitatively. It is found that the normal zone propagates non-uniformly in two dimensions within the YBCO layer. Two stages of normal zone propagation are observed. During the first stage, the normal zone propagates along the conductor length as the current and magnetic field redistribute within the YBCO layer. During the second stage, current sharing with the Cu begins and the magneto-optical image becomes constant. The normal zone propagation velocity at 45 K, I = 50 A (∼50% I c ), is determined as 22.7 mm s -1 using the time-dependent optical light intensity data. (rapid communication)

Provincial hydro expansions

Energy Technology Data Exchange (ETDEWEB)

Froschauer, K J

1993-01-01

A study of the development of five provincial hydroelectric utilities in Canada indicates that power companies and the state invited manufacturers to use hydroelectricity and natural resources in order to diversify provincial economies. These hydro expansions also show that utilities and government designed hydro projects to serve continental requirements; serving both objectives became problematic. It is argued that when the Canadian state and firms such as utilities use hydro expansions to serve both continentalism and industrialization, then at best they foster dependent industrialization and staple processing. At worst, they overbuild the infrastructure to generate provincial surplus energy for continental, rather than national, integration. Hydro developments became subject to state intervention in Canada mainly through the failures of private utilities to provide power for the less-lucrative industrial markets within provincial subregions. Although the state and utilities invited foreign firms to manufacture hydro equipment within the provinces and others to use electricity to diversify production beyond resource processing, such a diversification did not occur. Since 1962, ca 80% of industrial energy was used to semi-process wood-derived products, chemicals, and metals. The idea for a national power network became undermined by interprovincial political-economic factors and since 1963, the federal national/continential power policy prevailed. 187 refs., 6 figs., 52 tabs.

Magneto-induced large deformation and high-damping performance of a magnetorheological plastomer

International Nuclear Information System (INIS)

Liu, Taixiang; Gong, Xinglong; Xu, Yangguang; Pang, Haoming; Xuan, Shouhu

2014-01-01

A magnetorheological plastomer (MRP) is a new kind of soft magneto-sensitive polymeric composite. This work reports on the large magneto-deforming effect and high magneto-damping performance of MRPs under a quasi-statical shearing condition. We demonstrate that an MRP possesses a magnetically sensitive malleability, and its magneto-mechanical behavior can be analytically described by the magneto-enhanced Bingham fluid-like model. The magneto-induced axial stress, which drives the deformation of the MRP with 70 wt % carbonyl iron powder, can be tuned in a large range from nearly 0.0 kPa to 55.4 kPa by an external 662.6 kA m −1 magnetic field. The damping performance of an MRP has a significant correlation with the magnetic strength, shear rate, carbonyl iron content and shear strain amplitude. For an MRP with 60 wt % carbonyl iron powder, the relative magneto-enhanced damping effect can reach as high as 716.2% under a quasi-statically shearing condition. Furthermore, the related physical mechanism is proposed, and we reveal that the magneto-induced, particle-assembled microstructure directs the magneto-mechanical behavior of the MRP. (paper)

A comparison of the aquatic impacts of large hydro and small hydro projects

Science.gov (United States)

Taylor, Lara A.

The expansion of small hydro development in British Columbia has raised concerns surrounding the effects of these projects, and the provincial government's decision to proceed with Site C has brought attention to the impacts of large hydro. Together, these decisions highlight that there are impacts associated with all energy development. My study examines the aquatic effects of large and small hydro projects using two case study sites: Site C and the Upper Harrison Water Power Project. I first determine the aquatic effects of each of the case study sites. Next, I use existing literature and benefits transfer to determine the monetary value of these effects. My results suggest that, with mitigation, small hydro projects have less of an effect on the environment than a large hydro project per unit of electricity. I also describe the implications of my study in the context of current British Columbia energy policy. Keywords: hydropower; aquatic effects. Subject Terms: environmental impact assessment; benefits transfer.

Magneto-responsive liquid crystalline elastomer nanocomposites as potential candidates for dynamic cell culture substrates

Energy Technology Data Exchange (ETDEWEB)

Herrera-Posada, Stephany; Mora-Navarro, Camilo; Ortiz-Bermudez, Patricia; Torres-Lugo, Madeline [Department of Chemical Engineering, Call Box 9000, University of Puerto Rico, Mayagüez PR 00681 (Puerto Rico); McElhinny, Kyle M.; Evans, Paul G. [Department of Materials Science and Engineering, 1509 University Avenue, University of Wisconsin-Madison, WI 53706 (United States); Calcagno, Barbara O. [Department of General Engineering, Call Box 9000, University of Puerto Rico, Mayagüez PR 00681 (Puerto Rico); Acevedo, Aldo, E-mail: aldo.acevedo@upr.edu [Department of Chemical Engineering, Call Box 9000, University of Puerto Rico, Mayagüez PR 00681 (Puerto Rico)

2016-08-01

developed for potential applications in dynamic cell culture • Nanoparticles displaced the LC phase transition near physiological temperature without distortion of the LC order • Magnetic particles generate heat promoting the LCE's phase transition and contactless dynamic deformations • Magneto-induced dynamic deformations < 40 °C were achieved in the presence of common cell culture media • Collagen functionalization reduced LCEs hydrophobicity and enabled the attachment and proliferation of NIH3T3 fibroblasts.

Magneto-responsive liquid crystalline elastomer nanocomposites as potential candidates for dynamic cell culture substrates

International Nuclear Information System (INIS)

Herrera-Posada, Stephany; Mora-Navarro, Camilo; Ortiz-Bermudez, Patricia; Torres-Lugo, Madeline; McElhinny, Kyle M.; Evans, Paul G.; Calcagno, Barbara O.; Acevedo, Aldo

2016-01-01

developed for potential applications in dynamic cell culture • Nanoparticles displaced the LC phase transition near physiological temperature without distortion of the LC order • Magnetic particles generate heat promoting the LCE's phase transition and contactless dynamic deformations • Magneto-induced dynamic deformations < 40 °C were achieved in the presence of common cell culture media • Collagen functionalization reduced LCEs hydrophobicity and enabled the attachment and proliferation of NIH3T3 fibroblasts

Integrated operation of hydro thermal system

International Nuclear Information System (INIS)

Nanthakumar, J.

1994-01-01

Long-term power system expansion planning studies are carried out to meet the electricity requirement in the future. Prior to the expansion planning studies, it is essential to know the energy potential of the existing generating system, especially the hydro power plants. Detailed hydro thermal stimulation studies of the integrated system is therefore carried out to determine the best way to maximise the hydro energy of the existing and committed plants. The results of the integrated system simulated model are stored in numerous files and are available for retrieval. Most important output used for expansion analysis is the energy production of each hydro plant. The annual hydro energy potential of the total hydro system of Sri Lanka for the hydrological year from 1949 to 1988 is given. Hydro condition data with different probability levels are also indicated

Magneto-Optical Properties of Paramagnetic Superrotors

Science.gov (United States)

Milner, A. A.; Korobenko, A.; Floß, J.; Averbukh, I. Sh.; Milner, V.

2015-07-01

We study the dynamics of paramagnetic molecular superrotors in an external magnetic field. An optical centrifuge is used to create dense ensembles of oxygen molecules in ultrahigh rotational states. In is shown, for the first time, that the gas of rotating molecules becomes optically birefringent in the presence of a magnetic field. The discovered effect of "magneto-rotational birefringence" indicates the preferential alignment of molecular axes along the field direction. We provide an intuitive qualitative model, in which the influence of the applied magnetic field on the molecular orientation is mediated by the spin-rotation coupling. This model is supported by the direct imaging of the distribution of molecular axes, the demonstration of the magnetic reversal of the rotational Raman signal, and by numerical calculations.

Strategies for growth of hydro electric power

International Nuclear Information System (INIS)

Khera, D.V.

1998-01-01

Hydro power on account of its several inherent advantages has a key role to play in the development of long term energy strategies based on diversified and balance use of natural national resources. Our country is fortunate to be endowed with large hydro-electric potential. It is estimated that the hydro potential while fully developed may yield to an installed capacity of 1,50,000 MW. An attempt has been made in this paper to examine and analyse the status and trend of hydro power development, need for accelerated development of hydro power, myths about hydro electric projects, principal causes responsible for scaling down of hydro share in the total installed capacity and strategies which could restore optimum hydro thermal mix. (author)

Home grown hydro, part 1: Hydro development in Canada key to regional, international business expansion

International Nuclear Information System (INIS)

Wiebe, P.A.

1994-01-01

Canada has had a long and successful record of hydroelectric power development since the first hydraulic generators were installed at Chaudiere Falls near Ottawa in 1881. Canadian hydro engineers have demonstrated their ability to develop and manage higher voltages, longer transmission networks, larger projects, remote sites, and undersea cable technology. Canada has earned a reputation for excellence in the hydro industry and is successful at exporting its expertise to develop hydro resources in the international market. A prominent example is provided by the Three Gorges Project in China, for which the Chinese Ministry of Energy searched for the best foreign engineers to prepare a feasibility report. A Canadian team that integrated the expertise of hydro consultants, utilities, and major equipment suppliers was chosen to prepare the report, winning over teams from the USA, Brazil, and Europe. Success in this initiative is attributed to Canada's ability to demonstrate the favorable application of new technology at James Bay. Domestic hydro projects are thus seen as crucial in efforts to expand into international markets. However, Canada's new completed hydro capacity has fallen dramatically since 1986, and Canadian hydro contractors have tended to remain domestic operators with little incentive to enter foreign markets. By having the foresight to begin new hydro developments now, Canada would benefit from increased employment and orders for equipment, and would ensure a continuing base of technical expertise and innovation in the electrical industry. 2 figs

Home grown hydro, part 1: Hydro development in Canada key to regional, international business expansion

Energy Technology Data Exchange (ETDEWEB)

Wiebe, P.A

1994-06-01

Canada has had a long and successful record of hydroelectric power development since the first hydraulic generators were installed at Chaudiere Falls near Ottawa in 1881. Canadian hydro engineers have demonstrated their ability to develop and manage higher voltages, longer transmission networks, larger projects, remote sites, and undersea cable technology. Canada has earned a reputation for excellence in the hydro industry and is successful at exporting its expertise to develop hydro resources in the international market. A prominent example is provided by the Three Gorges Project in China, for which the Chinese Ministry of Energy searched for the best foreign engineers to prepare a feasibility report. A Canadian team that integrated the expertise of hydro consultants, utilities, and major equipment suppliers was chosen to prepare the report, winning over teams from the USA, Brazil, and Europe. Success in this initiative is attributed to Canada's ability to demonstrate the favorable application of new technology at James Bay. Domestic hydro projects are thus seen as crucial in efforts to expand into international markets. However, Canada's new completed hydro capacity has fallen dramatically since 1986, and Canadian hydro contractors have tended to remain domestic operators with little incentive to enter foreign markets. By having the foresight to begin new hydro developments now, Canada would benefit from increased employment and orders for equipment, and would ensure a continuing base of technical expertise and innovation in the electrical industry. 2 figs.

Numerical investigation of fully-developed magneto-hydro-dynamic flows in ducts

International Nuclear Information System (INIS)

Dajeh, D. A.

1996-01-01

In this paper a numerical study is presented for fuly developed magnetic-hydrodynamic flows in ducts under a uniform transverse implied magnetic field. Afinite different scheme comprising of modified ADI 'Alternating Direction Implicit' method and a SOUR 'Sucessive-Over and under relaxation' method are used to solve the set of governing equations. Computations are carried out for a different shape of ducts over a wide range of Hartman number, up to five thousands, which is an important parameter in the nuclear fusion reactor design. (author).16 refs., 7 figs., 3 tabs

Development of seed separation techniques in magneto hydro dynamic power plant

Energy Technology Data Exchange (ETDEWEB)

Nagalakshmi, R; Balasubramanian, V [Bharat Heavy Electricals Ltd., Tiruchirapalli (India); Pandey, S K [Regional Engineering College, Tiruchirapalli (India)

1994-06-01

Approximately 90% of potassium is recovered in the various magnetohydrodynamics (MHD) downstream components as spent-seed. In this work, countercurrent extraction process to recover water-soluble potassium from spent-seed is developed. Synthetic spent-seed solids were prepared at simulated MHD conditions. Different dissolution experiments at various process conditions to recover water-soluble/insoluble potassium from spent-seed are reported in this paper. Lime digestion and acid digestion options are suggested to recover water-insoluble potassium from spent-seed. 90% of potassium interacted with water-insoluble portion of the spent-seed. It was observed that 80% water-insoluble potassium could be recovered from acid leaching. (author). 4 refs., 4 tabs.

A magneto rheological hybrid damper for railway vehicles suspensions

Directory of Open Access Journals (Sweden)

Gheorghe GHITA

2012-09-01

Full Text Available High speed railway vehicles features a specific lateral oscillation resulting from the coupled lateral displacement and yaw of the wheelset which leads to a sinusoid movement of the wheelset along the track, transferred to the entire vehicle. The amplitude of this oscillation is strongly dependant on vehicle’s velocity. Over a certain value, namely the critical speed, the instability phenomenon so-called hunting occurs. To raise the vehicle’s critical speed different designs of the suspension all leading to a much stiffer vehicle can be envisaged. Different simulations prove that a stiffer central suspension will decrease the passenger’s comfort in terms of lateral accelerations of the carboy. The authors propose a semi-active magneto rheological suspension to improve the vehicle’s comfort at high speeds. The suspension has as executive elements hybrid magneto rheological dampers operating under sequential control strategy type balance logic. Using an original mathematical model for the lateral dynamics of the vehicle the responses of the system with passive and semi-active suspensions are simulated. It is shown that the semi-active suspension can improve the vehicle performances.

Magneto-radiotherapy: using magnetic fields to guide dose deposition

International Nuclear Information System (INIS)

Nettelbeck, H.; Lerch, M.; Takacs, G.; Rosenfeld, A.

2006-01-01

Full text: Magneto-radiotherapy is the application of magnetic fields during radiotherapy procedures. It aims to improve the quality of cancer treatment by using magnetic fields to 1 g uide the dose-deposition of electrons in tissue. Monte Carlo (MC) studies have investigated magneto-radiotherapy applied to conventional photon and electron linac beams. In this study, a combination of MC PENELOPE simulations and physical experiments were done to investigate magneto-radiotherapy applied to MRT (Microbeam Radiation Therapy) and conventional linac radiotherapy.

[Ontario Hydro]. Corporate performance report, 1994

International Nuclear Information System (INIS)

1995-01-01

Summarizes Ontario Hydro's corporate performance for the year, with actual results being compared against planned values. Also includes additional indicators that illustrate noteworthy trends in corporate performance. Corporate results are reported under the new organizational structure implemented in 1993, beginning with overall results in such areas as customer service, environmental stewardship, human resources, and finance. This is followed by reports from the Generation Business Group, Customer Services Group, Corporate Business Group, General Counsel and Secretary, Ontario Hydro Audit, Strategic Planning, Environment and Communication Group, and Ontario Hydro enterprises (Ontario Hydro Technologies, Ontario Hydro International). The appendix includes summary financial statements

High-frequency magneto-impedance in metastable metallic materials: An overview

International Nuclear Information System (INIS)

Vinai, F.; Coisson, M.; Tiberto, P.

2006-01-01

The giant magneto-impedance effect (GMI) is a common feature of a wide class of metastable ferromagnetic alloys. This effect can be enhanced by submitting the as-prepared materials to suitable thermal treatments. Recently, a remarkably high magneto-impedance response has been observed in the GHz region for several systems. The increase in miniaturization of telecommunication devices dramatically increases the working frequencies; as a consequence, the interest in studying magneto-impedance effect leads to microwave region. In this paper, analogies and differences among the magneto-transport effect observed in ferromagnetic metastable alloys will be highlighted and discussed from the experimental point of view in a wide range of frequencies

A framework for quantification of groundwater dynamics - concepts and hydro(geo-)logical metrics

Science.gov (United States)

Haaf, Ezra; Heudorfer, Benedikt; Stahl, Kerstin; Barthel, Roland

2017-04-01

similarity classification framework for groundwater hydrographs. However, the overabundance of metrics available calls for a systematic redundancy analysis of the metrics, which we describe in a second study (Heudorfer et al., 2017). Heudorfer, B., Haaf, E., Barthel, R., Stahl, K., 2017. A framework for quantification of groundwater dynamics - redundancy and transferability of hydro(geo-)logical metrics. EGU General Assembly 2017, Vienna, Austria.

Magneto-optical response in bimetallic metamaterials

Science.gov (United States)

Atmatzakis, Evangelos; Papasimakis, Nikitas; Fedotov, Vassili; Vienne, Guillaume; Zheludev, Nikolay I.

2018-01-01

We demonstrate resonant Faraday polarization rotation in plasmonic arrays of bimetallic nano-ring resonators consisting of Au and Ni sections. This metamaterial design allows the optimization of the trade-off between the enhancement of magneto-optical effects and plasmonic dissipation. Nickel sections corresponding to as little as 6% of the total surface of the metamaterial result in magneto-optically induced polarization rotation equal to that of a continuous nickel film. Such bimetallic metamaterials can be used in compact magnetic sensors, active plasmonic components, and integrated photonic circuits.

Magneto-photoconductivity of three dimensional topological insulator bismuth telluride

Science.gov (United States)

Cao, Bingchen; Eginligil, Mustafa; Yu, Ting

2018-03-01

Magnetic field dependence of the photocurrent in a 3D topological insulator is studied. Among the 3D topological insulators bismuth telluride has unique hexagonal warping and spin texture which has been studied by photoemission, scanning tunnelling microscopy and transport. Here, we report on low temperature magneto-photoconductivity, up to 7 T, of two metallic bismuth telluride topological insulator samples with 68 and 110 nm thicknesses excited by 2.33 eV photon energy along the magnetic field perpendicular to the sample plane. At 4 K, both samples exhibit negative magneto-photoconductance below 4 T, which is as a result of weak-antilocalization of Dirac fermions similar to the previous observations in electrical transport. However the thinner sample shows positive magneto-photoconductance above 4 T. This can be attributed to the coupling of surface states. On the other hand, the thicker sample shows no positive magneto-photoconductance up to 7 T since there is only one surface state at play. By fitting the magneto-photoconductivity data of the thicker sample to the localization formula, we obtain weak antilocalization behaviour at 4, 10, and 20 K, as expected; however, weak localization behaviour at 30 K, which is a sign of surface states masked by bulk states. Also, from the temperature dependence of phase coherence length bulk carrier-carrier interaction is identified separately from the surface states. Therefore, it is possible to distinguish surface states by magneto-photoconductivity at low temperature, even in metallic samples.

Small hydro

International Nuclear Information System (INIS)

Bennett, K.; Tung, T.

1995-01-01

A small hydro plant in Canada is defined as any project between 1 MW and 15 MW but the international standard is 10 MW. The global market for small hydro development was considered good. There are some 1000 to 2000 MW of generating capacity being added each year. In Canada, growth potential is considered small, primarily in remote areas, but significant growth is anticipated in Eastern Europe, Africa and Asia. Canada with its expertise in engineering, manufacturing and development is considered to have a good chance to take advantage of these growing markets

Micro Hydro-Electric Energy Generation- An Overview

OpenAIRE

S. O. Anaza; M. S. Abdulazeez; Y. A. Yisah; Y. O. Yusuf; B. U. Salawu; S. U. Momoh

2017-01-01

Energy is required now more than ever due to population growth, industrialization and modernization. Challenges such as carbon dioxide (CO2) emissions and depletion of conventional source of energy necessitate for renewable sources, of which hydro energy seems to be the most predictable. Micro-hydro which is hydro energy in a “small” scale provides electricity to small communities by converting hydro energy into electrical energy. This paper is an overview of micro-hydro system by reviewing s...

Magneto-dependent stress relaxation of magnetorheological gels

KAUST Repository

Xu, Yangguang; Liu, Taixiang; Liao, G J; Lubineau, Gilles

2017-01-01

The stress relaxation behaviors of magnetorheological (MR) gels under stepwise shear loading are systematically investigated. The particle-enhanced effect, the magneto-induced effect, and the temperature-enhanced effect on the stress relaxation of MR gels are discussed. For further analysis of the magneto-induced stress relaxation mechanism in MR gels, a phenomenological model is established to describe the stress relaxation behavior of the matrix and the magnetic particle chains. All characteristic parameters introduced in the model, i.e. relaxation time, instantaneous modulus, and stable modulus, have well-defined physical meanings and are fitted based on the experimental results. The influence of each parameter on the macroscopic response is discussed and it is found that the relaxation stress induced by the magneto-mechanical coupling effect plays an important role in the stress relaxation process of MR gels.

Magneto-dependent stress relaxation of magnetorheological gels

KAUST Repository

Xu, Yangguang

2017-09-01

The stress relaxation behaviors of magnetorheological (MR) gels under stepwise shear loading are systematically investigated. The particle-enhanced effect, the magneto-induced effect, and the temperature-enhanced effect on the stress relaxation of MR gels are discussed. For further analysis of the magneto-induced stress relaxation mechanism in MR gels, a phenomenological model is established to describe the stress relaxation behavior of the matrix and the magnetic particle chains. All characteristic parameters introduced in the model, i.e. relaxation time, instantaneous modulus, and stable modulus, have well-defined physical meanings and are fitted based on the experimental results. The influence of each parameter on the macroscopic response is discussed and it is found that the relaxation stress induced by the magneto-mechanical coupling effect plays an important role in the stress relaxation process of MR gels.

[Magneto-laser therapy of chronic gastritis in children and adolescents].

Science.gov (United States)

Zviagin, A A; Nikolaenko, E A

2008-01-01

The efficiency of transcutaneous magneto-laser treatment as a component of combined therapy of chronic gastritis in children and adolescents (aged 5-17 years) was compared with that of pharmacotherapy and low-intensity laser therapy. The patients were allocated to three groups of 25 persons each. Patients of group 1 were given only drug therapy, those in group 2 were treated with pharmaceuticals and low-intensity laser therapy. The patients comprising group 3 were subjected to the action of magneto-laser radiation. Magneto-laser therapy was shown to result in a significantly more expressed improvement of clinical and morphological characteristics of the patients compared with pharmacotherapy alone. There was no significant difference between effects of magneto-laser and low-intensity laser radiation.

Synthesis of immunotargeted magneto-plasmonic nanoclusters.

Science.gov (United States)

Wu, Chun-Hsien; Sokolov, Konstantin

2014-08-22

Magnetic and plasmonic properties combined in a single nanoparticle provide a synergy that is advantageous in a number of biomedical applications including contrast enhancement in novel magnetomotive imaging modalities, simultaneous capture and detection of circulating tumor cells (CTCs), and multimodal molecular imaging combined with photothermal therapy of cancer cells. These applications have stimulated significant interest in development of protocols for synthesis of magneto-plasmonic nanoparticles with optical absorbance in the near-infrared (NIR) region and a strong magnetic moment. Here, we present a novel protocol for synthesis of such hybrid nanoparticles that is based on an oil-in-water microemulsion method. The unique feature of the protocol described herein is synthesis of magneto-plasmonic nanoparticles of various sizes from primary blocks which also have magneto-plasmonic characteristics. This approach yields nanoparticles with a high density of magnetic and plasmonic functionalities which are uniformly distributed throughout the nanoparticle volume. The hybrid nanoparticles can be easily functionalized by attaching antibodies through the Fc moiety leaving the Fab portion that is responsible for antigen binding available for targeting.

A framework for quantification of groundwater dynamics - redundancy and transferability of hydro(geo-)logical metrics

Science.gov (United States)

Heudorfer, Benedikt; Haaf, Ezra; Barthel, Roland; Stahl, Kerstin

2017-04-01

, which are readily available for usage in studies on groundwater dynamics, intended to help overcome analytical limitations that exist due to the complexity of groundwater dynamics. Haaf, E., Heudorfer, B., Stahl, K., Barthel, R., 2017. A framework for quantification of groundwater dynamics - concepts and hydro(geo-)logical metrics. EGU General Assembly 2017, Vienna, Austria.

Magneto-Seebeck effect in magnetic tunnel junctions with perpendicular anisotropy

Directory of Open Access Journals (Sweden)

Keyu Ning

2017-01-01

Full Text Available As one invigorated filed of spin caloritronics combining with spin, charge and heat current, the magneto-Seebeck effect has been experimentally and theoretically studied in spin tunneling thin films and nanostructures. Here we analyze the tunnel magneto-Seebeck effect in magnetic tunnel junctions with perpendicular anisotropy (p-MTJs under various measurement temperatures. The large tunnel magneto-Seebeck (TMS ratio up to −838.8% for p-MTJs at 200 K is achieved, with Seebeck coefficient S in parallel and antiparallel states of 6.7 mV/K and 62.9 mV/K, respectively. The temperature dependence of the tunnel magneto-Seebeck can be attributed to the contributing transmission function and electron states at the interface between CoFeB electrode and MgO barrier.

Small hydro: Policy and potential in Spain

International Nuclear Information System (INIS)

Gutierrez, C.

2001-01-01

In Spain, the benefits of small-scale (less than 10 MW) hydro are apparently rarely appreciated and there is little support from European institutions. The article suggests that small hydro technology can make a significant contribution to the country's energy requirements and create employment, provided certain obstacles can be removed. Data on the number of small hydros in Spain, and of recent installations are given; the share of hydro in Spain's total energy production is 2.5%. The low environmental impact of hydro is extolled, and the conclusions of a recent study of 'environmental impacts of the production of electricity' are listed. There are said to be unreasonable administrative obstacles; for example, it is more difficult to obtain permission to refurbish a 100 kW hydro plant in Castilla y Leon than it is to install a 30,000 kW gas plant. Some details relating to the affect of hydro on aquatic ecosystems, noise levels, and water quality, are given

Large magneto-conductance and magneto-electroluminescence in exciplex-based organic light-emitting diodes at room temperature

Science.gov (United States)

Ling, Yongzhou; Lei, Yanlian; Zhang, Qiaoming; Chen, Lixiang; Song, Qunliang; Xiong, Zuhong

2015-11-01

In this work, we report on large magneto-conductance (MC) over 60% and magneto-electroluminescence (MEL) as high as 112% at room temperature in an exciplex-based organic light-emitting diode (OLED) with efficient reverse intersystem crossing (ISC). The large MC and MEL are individually confirmed by the current density-voltage characteristics and the electroluminescence spectra under various magnetic fields. We proposed that this type of magnetic field effect (MFE) is governed by the field-modulated reverse ISC between the singlet and triplet exciplex. The temperature-dependent MFEs reveal that the small activation energy of reverse ISC accounts for the large MFEs in the present exciplex-based OLEDs.

Surface effects on anti-plane shear waves propagating in magneto-electro-elastic nanoplates

International Nuclear Information System (INIS)

Wu, Bin; Zhang, Chunli; Chen, Weiqiu; Zhang, Chuanzeng

2015-01-01

Material surfaces may have a remarkable effect on the mechanical behavior of magneto-electro-elastic (or multiferroic) structures at nanoscale. In this paper, a surface magneto-electro-elasticity theory (or effective boundary condition formulation), which governs the motion of the material surface of magneto-electro-elastic nanoplates, is established by employing the state-space formalism. The properties of anti-plane shear (SH) waves propagating in a transversely isotropic magneto-electro-elastic plate with nanothickness are investigated by taking surface effects into account. The size-dependent dispersion relations of both antisymmetric and symmetric SH waves are presented. The thickness-shear frequencies and the asymptotic characteristics of the dispersion relations considering surface effects are determined analytically as well. Numerical results show that surface effects play a very pronounced role in elastic wave propagation in magneto-electro-elastic nanoplates, and the dispersion properties depend strongly on the chosen surface material parameters of magneto-electro-elastic nanoplates. As a consequence, it is possible to modulate the waves in magneto-electro-elastic nanoplates through surface engineering. (paper)

Tuning Coler Magnetic Current Apparatus with Magneto-Acoustic Resonance

Science.gov (United States)

Ludwig, Thorsten

An attempt was made to tune the Coler magnetic current apparatus with the magneto acoustic resonance of the magnetic rods. Measurements with a replica of the famous Coler "Magnetstromapparat" were conducted. In order to tune the acoustic, magnetic and electric resonance circuits of the Coler device the magneto-acoustic resonance was measured with a frequency scan through a function generator and a lock-in amplifier. The frequency generator was powering a driving coil, while the lock-in was connected to a pickup coil. Both coils were placed on a magnetic rod. Resonances were observed up to the 17th harmonic. The quality Q of the observed resonances was 270. To study the magneto-acoustic resonance in the time domain a pair of Permendur rods were employed. The magneto-acoustic resonances of the Permendur rods were observed with an oscilloscope. Spectra of the magneto acoustic resonance were measured for the Permendur rods and for a Coler replica magnet in the frequency range from 25 kHz to 380 kHz. The next step was to bring the resonances of the Permendur rods close together so that they overlap. The 10thharmonic was chosen because it was close to the 180 kHz that Hans Coler related to ferromagnetism. Further more magneto-acoustic coupling between the Permendur rods was studied. Finally the question was explored if Hans Coler converted vacuum fluctuations via magnetic and acoustic resonance into electricity. There is a strong connection between magnetism and quantum field zero point energy (ZPE). An outlook is given on next steps in the experiments to unveil the working mechanism of the Coler magnetic current apparatus.

BC hydro: Annual report, 1991-1992

Energy Technology Data Exchange (ETDEWEB)

1992-01-01

The third largest electric utility in Canada, B.C. Hydro services almost 1.3 million customers in an area containing over 92 per cent of British Columbia's population. B.C. Hydro's mission is to generate, transmit and distribute electricity. This annual report covers the business and financial performance of B.C. Hydro, and financial statistics.

Development and applications of reactor noise analysis at Ontario Hydro's CANDU reactors

International Nuclear Information System (INIS)

Gloeckler, O.; Tulett, M.V.

1995-01-01

In 1992 a program was initiated to establish reactor noise analysis as a practical tool for plant performance monitoring and system diagnostics in Ontario Hydro's CANDU reactors. Since then, various CANDU-specific noise analysis applications have been developed and validated. The noise-based statistical techniques are being successfully applied as powerful troubleshooting and diagnostic tools to a wide variety of actual operational I and C problems. The dynamic characteristics of critical plant components, instrumentation and processes are monitored on a regular basis. Recent applications of noise analysis include (1) validating the dynamics of in-core flux detectors (ICFDS) and ion chambers, (2) estimating the prompt fraction ICFDs in noise measurements at full power and in power rundown tests, (3) identifying the cause of excessive signal fluctuations in certain flux detectors, (4) validating the dynamic coupling between liquid zone control signals, (5) detecting and monitoring mechanical vibrations of detector tubes induced by moderator flow, (6) estimating the dynamics and response time of RTD (Resistance Temperature Detector) temperature signals, (7) isolating the cause of RTD signal anomalies, (8) investigating the source of abnormal flow signal behaviour, (9) estimating the overall response time of flow and pressure signals, (10) detecting coolant boiling in fully instrumented fuel channels, (11) monitoring moderator circulation via temperature noise, and (12) predicting the performance of shut-off rods. Some of these applications are performed on an as-needed basis. The noise analysis program, in the Pickering-B station alone, has saved Ontario Hydro millions of dollars during its first three years. The results of the noise analysis program have been also reviewed by the regulator (Atomic Energy Control Board of Canada) with favorable results. The AECB have expressed interest in Ontario Hydro further exploiting the use of noise analysis technology. (author

Performance of magneto-optical glass in optical current transducer application

International Nuclear Information System (INIS)

Shen, Yan; Lu, Yunhe; Liu, Zhao; Yu, Xueliang; Zhang, Guoqing; Yu, Wenbin

2015-01-01

First, a theoretical analysis was performed on the effect of temperature on the performance of the sensing element of paramagnetic rare earth-doped magneto-optical glass material that can be used in an optical current transducer application. The effect comprises two aspects: the linear birefringence and the Verdet constant. On this basis, rare earth-doped glass temperature characteristics were studied, and the experimental results indicated that the linear birefringence of rare earth-doped glass increased with increasing temperature, while its magneto-optical sensitivity decreased. Comparative experiments performed for various concentrations of rare earth dopant in the glass revealed that changes in the dopant concentration had no significant effect on the performance of magneto-optical glass. At last, a comparison between rare earth-doped magneto-optical and diamagnetic dense flint glass showed that the sensitivity of the former was six times that of the latter, although the temperature stability of the former was poorer. - Highlights: • Theoretical analysis on the effects of temperature on RE glass. • Rare earth doping leads to higher magneto-optical sensitivity. • The sensitivity of the RE glass is six times that of the dense flint glass

Comparison of the magneto-Peltier and magneto-Seebeck effects in magnetic tunnel junctions

NARCIS (Netherlands)

Shan, J.; Dejene, F. K.; Leutenantsmeyer, J. C.; Flipse, J.; Munzenberg, M.; van Wees, B. J.

2015-01-01

Understanding heat generation and transport processes in a magnetic tunnel junction (MTJ) is a significant step towards improving its application in current memory devices. Recent work has experimentally demonstrated the magneto-Seebeck effect in MTJs, where the Seebeck coefficient of the junction

User oriented end-station on VUV pump-probe magneto-optical ellipsometry at ELI beamlines

Science.gov (United States)

Espinoza, Shirly; Neuber, Gerd; Brooks, Christopher D.; Besner, Bastian; Hashemi, Maryam; Rübhausen, Michael; Andreasson, Jakob

2017-11-01

A state of the art ellipsometer for user operations is being implemented at ELI Beamlines in Prague, Czech Republic. It combines three of the most promising and exotic forms of ellipsometry: VUV, pump-probe and magneto-optical ellipsometry. This new ellipsometer covers a spectral operational range from the NIR up to the VUV, with high through-put between 1 and 40 eV. The ellipsometer also allows measurements of magneto-optical spectra with a 1 kHz switchable magnetic field of up to 1.5 T across the sample combining ellipsometry and Kerr spectroscopy measurements in an unprecedented spectral range. This form of generalized ellipsometry enables users to address diagonal and off-diagonal components of the dielectric tensor within one measurement. Pump-probe measurements enable users to study the dynamic behaviour of the dielectric tensor in order to resolve the time-domain phenomena in the femto to 100 ns range.

Analyze the factors effecting the development of hydro power projects in hydro rich regions of India

Directory of Open Access Journals (Sweden)

Ameesh Kumar Sharma

2016-09-01

Full Text Available Power is considered as the major back bone for all the nations throughout the world including India on the basis of which development of the country depends. If a country has the resources to generate the power at competitive price in that case the people of the country get the benefits in terms of improvement in their social and economical life. When we talk about India, various locations in the country where still there is no electricity people are living in dark without having the access of the modern technology. The total hydro power potential of India is 1, 50,000 MW out of this total hydro potential only 40,195 MW is exploited till 2014. More than 80% of the total hydro potential of the country is lying in the western Himalayan states (Jammu and Kashmir, Himachal Pradesh, Uttrakhand and Arunachal Pradesh. Small hydro projects are also playing a very important role in the modern world for the development of the remote areas which are not main grid connected specially in western Himalayan region of India. India has a total potential 19,749 MW of small hydro projects and of this total potential only 3990.9 MW harnessed till 2014. Ministry of new and renewable energy in India is also providing special incentives to hydro rich states of India. In this research article we are taken the case study of the small hydro projects in the western Himalayan region because theses states are having vast small hydro potential which is still needed to be harnessed. So, it is very important to identify the factors which are effecting the development of these small ventures especially in western Himalayan region in India.

Hydro-Quebec strategic plan 2006-2010

International Nuclear Information System (INIS)

2006-01-01

Hydro-Quebec produces, transmits and distributes electricity through the use of renewable energy sources, particularly hydroelectricity. It also conducts research in energy related fields. This document listed the strategic plan for Hydro-Quebec's 4 main divisions: Hydro-Quebec Production, Hydro-Quebec TransEnergie, Hydro-Quebec Distribution and Hydro-Quebec Energy Society of Bay James. The 2006 to 2010 strategic plan continues to focus on 3 main priorities: energy efficiency; complementary development of hydroelectricity and wind power; and, technological innovation. Hydro-Quebec's objectives also include strengthening the security of Quebec's energy supply and making use of energy as a lever for economic development. The plan for Hydro-Quebec Production calls for accelerating the development of major hydroelectric projects and promoting other renewable forms of energy such as wind power and ensuring the efficiency and reliability of the generating fleet. The utility's objective is to reach 4.7 TWh in energy savings by 2010 and to work toward a target of 8 TWh by 2015. The plan also involves a portfolio of hydroelectric projects totaling 5,400 MW. The plan includes complementary development and integration of 4,000 MW of windpower by 2015. The plan for Hydro-Quebec TransEnergie calls for system reliability and becoming a world benchmark for quality and reliability in wind power integration and deployment of new technologies to enhance performance. The plan for Hydro-Quebec Distribution calls for more efficient use of electricity, increase customer satisfaction and meet electricity needs through the use of renewable energy sources. The utility has made a commitment for 2006 to 2010 to a net income of $2.5 billion per year for a total of $12.5 billion, and a capital investment of 19.4 billion. This paper outlined the contribution of each division to net income and listed the economic benefits for the 2006 to 2010 period. In 2006, the Quebec Energy Board authorized

Temporal variations of NDVI and correlations between NDVI and hydro-climatological variables at Lake Baiyangdian, China.

Science.gov (United States)

Wang, Fei; Wang, Xuan; Zhao, Ying; Yang, Zhifeng

2014-09-01

In this paper, correlations between vegetation dynamics (represented by the normalized difference vegetation index (NDVI)) and hydro-climatological factors were systematically studied in Lake Baiyangdian during the period from April 1998 to July 2008. Six hydro-climatological variables including lake volume, water level, air temperature, precipitation, evaporation, and sunshine duration were used, as well as extracted NDVI series data representing vegetation dynamics. Mann-Kendall tests were used to detect trends in NDVI and hydro-climatological variation, and a Bayesian information criterion method was used to detect their abrupt changes. A redundancy analysis (RDA) was used to determine the major hydro-climatological factors contributing to NDVI variation at monthly, seasonal, and yearly scales. The results were as follows: (1) the trend analysis revealed that only sunshine duration significantly increased over the study period, with an inter-annual increase of 3.6 h/year (p NDVI trends were negligible; (2) the abrupt change detection showed that a major hydro-climatological change occurred in 2004, when abrupt changes occurred in lake volume, water level, and sunlight duration; and (3) the RDA showed that evaporation and temperature were highly correlated with monthly changes in NDVI. At larger time scales, however, water level and lake volume gradually became more important than evaporation and precipitation in terms of their influence on NDVI. These results suggest that water availability is the most important factor in vegetation restoration. In this paper, we recommend a practical strategy for lake ecosystem restoration that takes into account changes in NDVI.

Hydro-power: a long history, a bright future

Energy Technology Data Exchange (ETDEWEB)

Deudney, D

1981-07-01

A brief history of the spread of hydro-power in the world was given. Tables showing hydro-power potential and use, and the % electricity from hydro-power for 13 countries were included along with a graph showing % hydro-power operating, planned and under construction by region. The need for committed and farsighted political leadership for future development and the possibility of hydro production reaching 4 to 6 times its present level were discussed.

77 FR 77070 - Black Bear Hydro Partners, LLC;

Science.gov (United States)

2012-12-31

... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Project No. 2727-086] Black Bear Hydro...: October 24, 2012. d. Submitted By: Black Bear Hydro Partners, LLC (Black Bear Hydro). e. Name of Project... designating Black Bear Hydro as the Commission's non-federal representative for carrying out informal...

Scanning laser techniques for dynamic thermo-magnetic recording onto stationary media

Energy Technology Data Exchange (ETDEWEB)

Clegg, Warwick; Jenkins, David; Helian, Na; Windmill, James; Windmill, Robert; Atkinson, Ron; Hendren, Bill; Wright, C. David

2002-09-01

Scanning laser microscopes (SLMs) have been used to characterise the magnetic properties of materials for some time (J. Magn. Magn. Mater. 95(1) (1991); IEEE Trans. Magn. 31(6 Pt. 1) (1995)). An SLM has been designed to facilitate a number of operating modes: both for writing and reading magneto-optical data. The current SLM is capable of thermo-magnetically recording bits onto magneto-optical thin films. Unlike previous SLMs, the current instrument has been designed to write bits both statically and dynamically onto stationary media. It will be used to write to magneto-optic (MO) disk material thermo-magnetically prior to imaging. Images may be derived from the longitudinal and polar magneto-optic Kerr effects, which are wavelength dependent, using the appropriate laser wavelength. In this paper the two configurations for dynamic recording are described.

Scanning laser techniques for dynamic thermo-magnetic recording onto stationary media

International Nuclear Information System (INIS)

Clegg, Warwick; Jenkins, David; Helian, Na; Windmill, James; Windmill, Robert; Atkinson, Ron; Hendren, Bill; Wright, C. David

2002-01-01

Scanning laser microscopes (SLMs) have been used to characterise the magnetic properties of materials for some time (J. Magn. Magn. Mater. 95(1) (1991); IEEE Trans. Magn. 31(6 Pt. 1) (1995)). An SLM has been designed to facilitate a number of operating modes: both for writing and reading magneto-optical data. The current SLM is capable of thermo-magnetically recording bits onto magneto-optical thin films. Unlike previous SLMs, the current instrument has been designed to write bits both statically and dynamically onto stationary media. It will be used to write to magneto-optic (MO) disk material thermo-magnetically prior to imaging. Images may be derived from the longitudinal and polar magneto-optic Kerr effects, which are wavelength dependent, using the appropriate laser wavelength. In this paper the two configurations for dynamic recording are described

Holes in magneto electrostatic traps

International Nuclear Information System (INIS)

Jones, R.

1996-01-01

We observe that in magneto electrostatic confinement (MEC) devices the magnetic surfaces are not always equipotentials. The lack of symmetry in the equipotential surfaces can result in holes in MEC plasma traps. (author)

New markets for small-scale hydro

International Nuclear Information System (INIS)

Maurer, E.A.

1997-01-01

The market for small and medium sized hydro-electric power plant is more attractive than ever. The boom in Europe has increasingly spread to the emerging countries, and here too small hydro plays an important ecological role. In addition to new plant rehabilitation of 'historical' plant is now a major factor. The last few years have seen a market shift from single machine components to complete plant and systems, requiring a strategy re-think on the part of larger companies. Following the influx of private capital into the power industry, business conditions have also undergone a thorough transformation. In place of 'fast money', hydro power offers the prospect of earning longer-term, sustainable money'. The term small-scale hydro-electric power (or simply 'small hydro') is used slightly differently depending on the country and market. Here, it is used to denote plant with turbines up to 10 MW. (Author)

Feedback-type giant magneto-impedance sensor based on longitudinal excitation

International Nuclear Information System (INIS)

Zhao Wen; Bu Xiongzhu; Yu Geliang; Xiang Chao

2012-01-01

In this paper, the characteristics of Fe-based amorphous ribbon based on the longitudinal excitation are investigated with assistance of the theory of the giant magneto-impedance (GMI) effect. A feedback-type GMI micro-magnetic sensor is designed with regard to the design of the sensing element, the excitation circuit, the conditional circuit and the feedback circuit. With the analysis of the dynamic and static characteristics of the feedback-type GMI sensor, it is concluded that the designed feedback-type GMI sensor has higher linearity, stability and dynamic characteristics than non-feedback-type GMI sensor in −2.5 to +2.5 Oe. - Highlights: ► A feedback-type GMI micro-magnetic sensor is designed. ► Excitation coil and feedback coil of the sensor is designed to be in one. ► The feedback-type sensor has higher linearity and stability than non-feedback type. ► The feedback-type sensor has better dynamic characteristics than non-feedback type.

[Ontario Hydro]. Corporate performance report, 1993

International Nuclear Information System (INIS)

1994-01-01

Summarizes Ontario Hydro's corporate performance for the year, with actual results being compared against planned values established in the approved corporate financial plan and work program budget. Also includes additional indicators that illustrate noteworthy trends in corporate performance. Corporate results are reported under the new organizational structure implemented in mid-1993, beginning with overall results in such areas as customer satisfaction, electricity sales, human resources, and environmental protection. This is followed by reports from the Electricity Group (supply, generation, transmission), the Energy Services and Environment Group (load saved and shifted, non-utility generation, retail distribution), and Ontario Hydro enterprises (Ontario Hydro Technologies, Ontario Hydro International). The appendix contains summary financial statements

Standardized CSR and climate performance: why is Shell willing, but Hydro reluctant?; Shell; Hydro

Energy Technology Data Exchange (ETDEWEB)

Boasson, Elin Lerum; Wettestad, Joergen

2007-06-15

This report aims to contribute to the ongoing discussion concerning whether CSR merely serves to streamline company rhetoric or also has an influence on actual efforts. We discuss the tangible effects of CSR instruments on the climate-related rules and performances of the two different oil companies Hydro and Shell. First we explore whether similar CSR instruments lead to similar climate-related rules and practices in the two companies. Both Hydro and Shell adhere to the Global Compact (GC), the Global Reporting Initiative (GRI), the Carbon Disclosure Project (CDP) and the Global Gas Flaring Reduction Public-Private Partnership (GGFR). The report concludes that the GC has not rendered any tangible effects in either of the companies. Concerning the other instruments, Hydro has only followed the instrument requirements that fit their initial approach, and refrained from all deviating requirements. Shell has been more malleable, but we have noted few effects on the actual emissions and business portfolio resulting from the instrument adherence. Second, we assess how the differing results of the similar CSR portfolio may be explained. The reluctant attitude of the leaders in Hydro and the strong CSR motivation of Shell's executives result in significant differences. Hydro executives are able to constrain the effects of the instrument adherence. With Shell we note the opposite pattern: Its leaders promoted the instruments to be translated into internal rules, but a general lack of hierarchical structures hinders them from governing the conduct of various sub-organisations. The very diversity of the Shell culture helps to explain why the efforts of its executives have resulted in limited impact. The strength of the Hydro culture makes the corporation resistant to the instruments. Moreover, Hydro is strikingly shielded by virtue of its strong position in Norway. In contrast, Shell is more strongly affected by the global field of petroleum and the global field of CSR

Waveguide-Plasmon Polaritons Enhance Transverse Magneto-Optical Kerr Effect

Directory of Open Access Journals (Sweden)

Lars E. Kreilkamp

2013-11-01

Full Text Available Magneto-optical effects in ferrimagnetic or ferromagnetic materials are usually too weak for potential applications. The transverse magneto-optical Kerr effect (TMOKE in ferromagnetic films is typically on the order of 0.1%. Here, we demonstrate experimentally the enhancement of TMOKE due to the interaction of particle plasmons in gold nanowires with a photonic waveguide consisting of magneto-optical material, where hybrid waveguide-plasmon polaritons are excited. We achieve a large TMOKE that modulates the transmitted light intensity by 1.5%, accompanied by high transparency of the system. Our concept may lead to novel devices of miniaturized photonic circuits and switches, which are controllable by an external magnetic field.

Good prospects for Portuguese small hydro industry

International Nuclear Information System (INIS)

Betamio de Almeida, A.; Serranho, H.

2000-01-01

The article outlines the history of hydro in Portugal and discusses the current position of small-scale hydro with particular reference to the Portuguese Small Hydro Association (AMPH). Encouraged by legislation, and the Valoren community programme (which defined investment incentives), many new small hydro projects sprang up in Portugal in the 1990s. In some areas of Portugal the water levels were higher than the urban centres where the water is required: how the problems of integrating power and water were addressed is described. The integration of power and irrigation schemes is also mentioned. In the wake of great expansion in the Portuguese hydro industry, there was a sharp reduction (in 1995-6) and the reasons for that are listed. The 1999 tariff was such that it is likely that small hydro will provide 3.8% of the electric power consumed nationally by 2010

Development of magneto-plasmonic nanoparticles for multimodal image-guided therapy to the brain.

Science.gov (United States)

Tomitaka, Asahi; Arami, Hamed; Raymond, Andrea; Yndart, Adriana; Kaushik, Ajeet; Jayant, Rahul Dev; Takemura, Yasushi; Cai, Yong; Toborek, Michal; Nair, Madhavan

2017-01-05

Magneto-plasmonic nanoparticles are one of the emerging multi-functional materials in the field of nanomedicine. Their potential for targeting and multi-modal imaging is highly attractive. In this study, magnetic core/gold shell (MNP@Au) magneto-plasmonic nanoparticles were synthesized by citrate reduction of Au ions on magnetic nanoparticle seeds. Hydrodynamic size and optical properties of magneto-plasmonic nanoparticles synthesized with the variation of Au ions and reducing agent concentrations were evaluated. The synthesized magneto-plasmonic nanoparticles exhibited superparamagnetic properties, and their magnetic properties contributed to the concentration-dependent contrast in magnetic resonance imaging (MRI). The imaging contrast from the gold shell part of the magneto-plasmonic nanoparticles was also confirmed by X-ray computed tomography (CT). The transmigration study of the magneto-plasmonic nanoparticles using an in vitro blood-brain barrier (BBB) model proved enhanced transmigration efficiency without disrupting the integrity of the BBB, and showed potential to be used for brain diseases and neurological disorders.

Hydro-energy; Energie hydraulique

Energy Technology Data Exchange (ETDEWEB)

Bacher, P. [Electricite de France (EDF), 75 - Paris (France); Tardieu, B. [Coyne et Bellier, 92 - Gennevilliers (France)

2005-07-01

The first part of this study concerns the different type of hydraulic works. The second part presents the big hydro-energy, its advantages and disadvantages, the industrial risks, the electric power transport network, the economy and the development perspectives. The third part presents the little hydro-energy, its advantages and disadvantages, the decentralized production and the development perspectives. (A.L.B.)

Scheduling of head-sensitive cascaded hydro systems : a comparison based on numerical simulation results

Energy Technology Data Exchange (ETDEWEB)

Catalao, J.P.S.; Mariano, S.J.P.S. [Beira Interior Univ., Covilha (Portugal). Dept. of Electromechanical Engineering; Mendes, V.M.F. [Superior Engineering Inst. of Lisbon, Lisbon (Portugal). Dept. of Electrical Engineering and Automation; Ferreira, L.A.F.M. [Technical Univ. of Lisbon, Superior Technical Inst., Lisbon (Portugal). Dept. of Electrical Engineering and Computers

2008-07-01

The electric power sector in Portugal and Spain has shifted from a traditional monopoly to a deregulated, competitive energy market. As such, hydroelectric facilities face the optimal challenge of how to make a profit by managing water resources without compromising future potential profit. As such, hydro scheduling is a key activity for hydroelectric power utilities because of its significant economic impact. It involves the optimal management of water inflows and storage in reservoirs. This paper considered the problem of short-term hydro scheduling, concerning head-sensitive cascaded reservoirs, and the algorithmic aspects of its solution. The authors proposed and compared optimization methods based on dynamic programming, and linear and nonlinear network programming. The comparison revealed a negligible extra computational effort in a realistic cascaded hydro system where the head depended on the stored water volume. 17 refs., 3 tabs., 7 figs.

Scheduling of head-sensitive cascaded hydro systems : a comparison based on numerical simulation results

International Nuclear Information System (INIS)

Catalao, J.P.S.; Mariano, S.J.P.S.; Mendes, V.M.F.; Ferreira, L.A.F.M.

2008-01-01

The electric power sector in Portugal and Spain has shifted from a traditional monopoly to a deregulated, competitive energy market. As such, hydroelectric facilities face the optimal challenge of how to make a profit by managing water resources without compromising future potential profit. As such, hydro scheduling is a key activity for hydroelectric power utilities because of its significant economic impact. It involves the optimal management of water inflows and storage in reservoirs. This paper considered the problem of short-term hydro scheduling, concerning head-sensitive cascaded reservoirs, and the algorithmic aspects of its solution. The authors proposed and compared optimization methods based on dynamic programming, and linear and nonlinear network programming. The comparison revealed a negligible extra computational effort in a realistic cascaded hydro system where the head depended on the stored water volume. 17 refs., 3 tabs., 7 figs

Hydro-power

International Nuclear Information System (INIS)

Piro, P.

2010-01-01

On average the hydro-power sector produces 12% of the electrical power in France. A quarter of this production might pass to another operator than EDF because the end of some grants is nearing (2012 for 12 installations). In France the power of rivers belongs to the state that gives operators grants to harness it. The allowance lasts 75 years usually but for installations below 4.5 MW a permanent and definitive grant is allowed. Most installations are ancient and their investment have been paid off since a long, so hydro-power is the most profitable renewable energy in France. A lot of bidders are expected. Each bid will be assessed on 3 criteria: -) the global energy efficiency of the waterfall, -) a balanced management of the water resource, and -) an economic and financial offer to the state. The balance between the different uses of water is getting more delicate to reach and this renewal of grants will be an opportunity for the state to impose a better preservation of the environment. In July 2008, the French government announced a program for the re launching of the hydro-power, this program has been reduced and now only 3000 GWh supplementary are expected by 2020. (A.C.)

Hexapole-compensated magneto-optical trap on a mesoscopic atom chip

DEFF Research Database (Denmark)

Jöllenbeck, S.; Mahnke, J.; Randoll, R.

2011-01-01

Magneto-optical traps on atom chips are usually restricted to small atomic samples due to a limited capture volume caused primarily by distorted field configurations. Here we present a magneto-optical trap based on a millimeter-sized wire structure which generates a magnetic field with minimized...... distortions. Together with the loading from a high-flux two-dimensional magneto-optical trap, we achieve a loading rate of 8.4×1010 atoms/s and maximum number of 8.7×109 captured atoms. The wire structure is placed outside of the vacuum to enable a further adaptation to new scientific objectives. Since all...

Combined photothermal therapy and magneto-motive ultrasound imaging using multifunctional nanoparticles

Science.gov (United States)

Mehrmohammadi, Mohammad; Ma, Li L.; Chen, Yun-Sheng; Qu, Min; Joshi, Pratixa; Chen, Raeanna M.; Johnston, Keith P.; Emelianov, Stanislav

2010-02-01

Photothermal therapy is a laser-based non-invasive technique for cancer treatment. Photothermal therapy can be enhanced by employing metal nanoparticles that absorb the radiant energy from the laser leading to localized thermal damages. Targeting of nanoparticles leads to more efficient uptake and localization of photoabsorbers thus increasing the effectiveness of the treatment. Moreover, efficient targeting can reduce the required dosage of photoabsorbers; thereby reducing the side effects associated with general systematic administration of nanoparticles. Magnetic nanoparticles, due to their small size and response to an external magnetic field gradient have been proposed for targeted drug delivery. In this study, we investigate the applicability of multifunctional nanoparticles (e.g., magneto-plasmonic nanoparticles) and magneto-motive ultrasound imaging for image-guided photothermal therapy. Magneto-motive ultrasound imaging is an ultrasound based imaging technique capable of detecting magnetic nanoparticles indirectly by utilizing a high strength magnetic field to induce motion within the magnetically labeled tissue. The ultrasound imaging is used to detect the internal tissue motion. Due to presence of the magnetic component, the proposed multifunctional nanoparticles along with magneto-motive ultrasound imaging can be used to detect the presence of the photo absorbers. Clearly the higher concentration of magnetic carriers leads to a monotonic increase in magneto-motive ultrasound signal. Thus, magnetomotive ultrasound can determine the presence of the hybrid agents and provide information about their location and concentration. Furthermore, the magneto-motive ultrasound signal can indicate the change in tissue elasticity - a parameter that is expected to change significantly during the photothermal therapy. Therefore, a comprehensive guidance and assessment of the photothermal therapy may be feasible through magneto-motive ultrasound imaging and

Hydro-thermal power flow scheduling accounting for head variations

International Nuclear Information System (INIS)

El-Hawary, M.E.; Ravindranath, K.M.

1992-01-01

In this paper the authors treat the problem of optimal economic operation of hydrothermal electric power systems with variable head hydro plants employing the power flow equations to represent the network. Newton's method is used to solve the problem for a number of test systems. A comparison with solutions with fixed head is presented. In general the optimal schedule requires higher slack bus and thermal power generation and cost in the case of variable head hydro plant than that required by the fixed head hydro plant in all demand periods. Correspondingly, the hydro generation is less in the case of variable head hydro plant compared to fixed head hydro plant. A negligible difference in voltage magnitudes in all the time intervals, but it is observed that slightly higher voltages occur in the case of the fixed head hydro plant. Higher power and energy losses occur in the case of variable head hydro plants compared to the fixed head hydro plants

Hydro One 2002 annual report

International Nuclear Information System (INIS)

2003-01-01

Financial information from Hydro One was presented and a review of its 2002 operations was made available for the benefit of shareholders. Hydro One is the largest electricity delivery company in Ontario and one of the largest in North America. It began operation in 1999 after Ontario Hydro restructured its delivery and generation entities. Hydro One now includes power transmission, power distribution and telecom, with transmission and distribution operations representing 99 per cent of its business. This report indicates that in 2002, the utility had strong financial performance with $344 million in net income. The utility met its health and safety targets, and established a customer advisory board to improve customer satisfaction. A layer of management at the executive level was eliminated to stream-line decision-making and enhance productivity. The electricity network was upgraded and maintained through $546 million in capital expenditures. Non-core functions were sold to ensure a better focus on the core business of electricity delivery. This report presents an operations review as well as consolidated financial statements and common share information including the accounts of Hydro One and its share of assets, liabilities, revenues, expenses and cash flows. Revenue and expenditure statements were summarized by source. tabs., figs

Ontario Hydro annual report 1985

International Nuclear Information System (INIS)

1986-04-01

Ontario Hydro is a corporation without share capital created by a special statute of the Province of Ontario in 1906. It now operates under the authority of the Power Corporation Act, R.S.O. 1980, Chapter 384, as amended, with broad powers to generate, supply and deliver electric power throughout the province. It is also authorized to produce and sell steam and hot water as primary products. The Corporation's prime objective is to supply the people of Ontario with electricity at the lowest feasible cost consistent with high safety and quality of service standards. Ontario Hydro's main activity is wholesaling electric power to municipal utilities in urban areas who, in turn, retail it to customers in their service areas. In 1985, approximately 3,166,000 customers were served by Ontario Hydro and the municipal utilities in the province. Ontario Hydro operates 81 hydraulic, fossil and nuclear generating stations and an extensive power grid across Ontario to meet the province's demands for electric energy. Interconnections with other systems place the Corporation in an extensive electrical grid that covers a large segment of the North American continent. Ontario Hydro is a financially self-sustaining corporation. The Province of Ontario guarantees bonds and notes issued to the public by the Corporation

Magneto-optical properties of InSb for terahertz applications

Directory of Open Access Journals (Sweden)

Jan Chochol

2016-11-01

Full Text Available Magneto-optical permittivity tensor spectra of undoped InSb, n-doped and p-doped InSb crystals were determined using the terahertz time-domain spectroscopy (THz-TDS and the Fourier transform far-infrared spectroscopy (far-FTIR. A Huge polar magneto-optical (MO Kerr-effect (up to 20 degrees in rotation and a simultaneous plasmonic behavior observed at low magnetic field (0.4 T and room temperature are promising for terahertz nonreciprocal applications. We demonstrate the possibility of adjusting the the spectral rage with huge MO by increase in n-doping of InSb. Spectral response is modeled using generalized magneto-optical Drude-Lorentz theory, giving us precise values of free carrier mobility, density and effective mass consistent with electric Hall effect measurement.

Mode conversion in magneto photonic crystal fibre

International Nuclear Information System (INIS)

Otmani, Hamza; Bouchemat, Mohamed; Hocini, Abdesselam; Boumaza, Touraya; Benmerkhi, Ahlem

2017-01-01

The first concept of an integrated isolator was based on nonreciprocal TE–TM mode conversion, the nonreciprocal coupling between these modes is caused by the Faraday rotation if the magnetization is aligned along the z–axis, parallel to mode propagation. We propose to study this magneto-optical phenomenon, by the simulation of magneto photonic crystal fibre (MPCF), it consists of a periodic triangular lattice of air-holes filled with magnetic fluid which consists of magnetic nanoparticles into a BIG (Bismuth Iron Garnet) fibre. We simulated the influence of gyrotropy and the wavelength, and calculated Faraday rotation and modal birefringence. In this fibre the light is guided by internal total reflection, like classical fibres. However it was shown that they could function on a mode conversion much stronger than conventional fibres. - Highlights: • We propose to study mode conversion TE–TM, by the simulation of magneto photonic crystal fibre (MPCF). • We simulated the influence of gyrotropy. • We simulated the wavelength. • We calculated Faraday rotation. • We calculated modal birefringence.

Taylor Hydro plant goes live

International Nuclear Information System (INIS)

Anon.

2000-01-01

The 12.75 MW Taylor Hydroelectric Plant in Magrath, Alberta, synchronized its generator with the Alberta Power Grid and began production in April 2000. The plant is located on Government of Alberta irrigation works and is owned by Canadian Hydro Developers. During the irrigation season the plant will generate approximately 40 million kilowatt hours of zero-emission 'green' power for consumption, enough to power 5,000 homes for a year. The Taylor plant is a joint venture with EPCOR Power Development Corporation, a wholly-owned subsidiary of EPCOR Inc., the City of Edmonton utility. Canadian Hydro Developers also owns a 19 MW wind plant and a 6 MW gas plant in Alberta and five other 'run of river' hydro plants in Ontario and British Columbia. The company is committed to the concept of low-impact power generation; its ownership of wind run-of-river hydro and gas-fired facilities is proof of that commitment

The influence of band Jahn-Teller effect and magnetic order on the magneto-resistance in manganite systems

Energy Technology Data Exchange (ETDEWEB)

Rout, G.C., E-mail: gcr@iopb.res.i [Condensed Matter Physics Group, Department of Applied Physics and Ballistics, F.M. University, Balasore, Orissa 756019 (India); Parhi, Nilima [Department of Physics, M.P.C. (Autonomous) College, Baripada, Orissa 757001 (India); Behera, S.N. [Institute of Material Science, Bhubaneswar 751004 (India)

2009-08-01

A model calculation is presented in order to study the magneto-resistivity through the interplay between magnetic and structural transitions for the manganite systems. The model consists of an orbitally doubly degenerate conduction band and a periodic array of local moments of the t{sub 2g} electrons. The band electrons interact with the local t{sub 2g} electrons via the s-f hybridization. The phonons interact with the band electrons through static and dynamic band Jahn-Teller (J-T) interaction. The model Hamiltonian including the above terms is solved for the single particle Green's functions and the imaginary part of the self-energy gives the electron relaxation time. Thus the magneto-resistivity (MR) is calculated from the Drude formula. The MR effect is explained near the magnetic and structural transition temperatures.

Ontario Hydro annual report 1986

Energy Technology Data Exchange (ETDEWEB)

1987-04-01

Ontario Hydro`s annual report of the financial position and activities for the year 1986 consists of their financial highlights; corporate profile; customer service and satisfaction; message from Chairman; message from President; 1986 in review; financial section; management report; five-year summary of financial statistics; and comparative statistics.

Fixing hydro - The forgotten renewable

International Nuclear Information System (INIS)

Nalder, N.

1992-01-01

Since the dawn of civilization, man has captured the energy potential of falling water, from the water wheels in the fertile crescent of ancient times to today's highly sophisticated conventional and pumped storage projects. As we approach the 21st century, electric energy captured from falling water provides 2.0 trillion kilowatt-hours (21.23 quadrillion Btu), roughly 20% of the world's electric energy. Of the 2.56 billion kilowatts of the world's installed electric generating capacity, hydropower accounts for 24%. Between 1980 and 1989, world generation of hydroelectric power rose from 1.7 trillion kWh to 2.0 trillion kWh. As of January 1, 1988, the US has 90.5 million kW of installed hydro capacity - 70.8 million kW of it under license by the Federal Energy Regulatory Commission - with annual generation estimated at just under 300 billion kWh. Hydro's share, which not long ago comprised 13% of the nation's total capacity, now is just a 9% share. The US has the option to choose one or another path for hydro. If policy makers are willing to coast on a cushion of cheap natural gas, they will continue to shun hydro and put obstacles in its path. But if they come to regard hydro as an attractive resource - as they did only recently - economically and environmentally, they will encourage more balance in resource policies. Believing that interest in a balanced national resource portfolio will grow, the author reviews the past and suggests a possible future course of reasonable development for hydro. The article concludes with some suggested principles that will be needed if the appropriate balance is to be found

A Novel Frequency Restoring Strategy of Hydro-PV Hybrid Microgrid

DEFF Research Database (Denmark)

Wei, Feng; Kai, Sun; Guan, Yajuan

2014-01-01

. The existence of frequency steady-state error and the slow active power/frequency dynamic response are inevitable. Therefore, a novel frequency restoring strategy for the hydro-PV hybrid microgrid based on the improved hierarchical control of PV systems is proposed in this paper. The output active power of PV......The conventional PV systems based on the voltage inverters only inject dispatched power to the utility grid when they work at a grid-connected mode in the hydro-PV hybrid microgrid. Due to the droop method employed for load sharing between generators, as well as the enormous inertia of system...... systems is controlled by an extra frequency restoring controller resided in the tertiary control level. The frequency steady-state error is eliminated through regulating and rebalancing the power flow between the hydropower and the PV system. The proposed strategy has verified through simulations...

Enhanced Faraday rotation in one dimensional magneto-plasmonic structure due to Fano resonance

Science.gov (United States)

Sadeghi, S.; Hamidi, S. M.

2018-04-01

Enhanced Faraday rotation in a new type of magneto-plasmonic structure with the capability of Fano resonance, has been reported theoretically. A magneto-plasmonic structure composed of a gold corrugated layer deposited on a magneto-optically active layer was studied by means of Lumerical software based on finite-difference time-domain. In our proposed structure, plasmonic Fano resonance and localized surface plasmon have induced enhancement in magneto-optical Faraday rotation. It is shown that the influence of geometrical parameters in gold layer offers a desirable platform for engineering spectral position of Fano resonance and enhancement of Faraday rotation.

Remote micro hydro

Energy Technology Data Exchange (ETDEWEB)

1985-03-01

The micro-hydro project, built on a small tributary of Cowley Creek, near Whitehorse, Yukon, is an important step in the development of alternative energy sources and in conserving expensive diesel fuel. In addition to demonstrating the technical aspects of harnessing water power, the project paved the way for easier regulatory procedures. The power will be generated by a 9 meter head and a 6 inch crossflow turbine. The 36 V DC power will be stored in three 12 V batteries and converted to ac on demand by a 3,800 watt inverter. The system will produce 1.6 kW or 14,016 kWh per year with a firm flow of 1.26 cfs. This is sufficient to supply electricity for household needs and a wood working shop. The project is expected to cost about $18,000 and is more economical than tying into the present grid system, or continuing to use a gasoline generator. An environmental study determined that any impact of the project on the stream would be negligible. It is expected that no other water users will be affected by the project. This pilot project in micro-hydro applications will serve as a good indicator of the viability of this form of alternate energy in the Yukon. The calculations comparing the micro-hydro and grid system indicate that the mico-hydro system is a viable source of inflation-proof power. Higher heads and larger flow resulting in ac generation in excess of 10 kW would yield much better returns than this project. 3 tabs.

Hydro turbine governor’s power control of hydroelectric unit with sloping ceiling tailrace tunnel

Science.gov (United States)

Fu, Liang; Wu, Changli; Tang, Weiping

2018-02-01

The primary frequency regulation and load regulation transient process when the hydro turbine governor is under the power mode of hydropower unit with sloping ceiling tailrace are analysed by field test and numerical simulation in this paper. A simulation method based on “three-zone model” to simulate small fluctuation transient process of the sloping ceiling tailrace is proposed. The simulation model of hydraulic turbine governor power mode is established by governor’s PLC program identification and parameter measurement, and the simulation model is verified by the test. The slow-fast-slow “three-stage regulation” method which can improve the dynamic quality of hydro turbine governor power mode is proposed. The power regulation strategy and parameters are optimized by numerical simulation, the performance of primary frequency regulation and load regulation transient process when the hydro turbine governor is under power mode are improved significantly.

Architecture at Hydro-Quebec. L'architecture a Hydro-Quebec

Energy Technology Data Exchange (ETDEWEB)

1991-01-01

Architecture at Hydro-Quebec is concerned not only with combining function and aesthetics in designing buildings and other structures for an electrical utility, but also to satisfy technical and administrative needs and to help solve contemporary problems such as the rational use of energy. Examples are presented of Hydro-Quebec's architectural accomplishments in the design of hydroelectric power stations and their surrounding landscapes, thermal power stations, transmission substations, research and testing facilities, and administrative buildings. It is shown how some buildings are designed to adapt to local environments and to conserve energy. The utility's policy of conserving installations of historic value, such as certain pre-1930 power stations, is illustrated, and aspects of its general architectural policy are outlined. 20 figs.

Magneto-paper electrophoresis in the separation of inorganic ions

International Nuclear Information System (INIS)

Mukherjee, H.G.; Datta, S.K.

1983-01-01

A comparative study of the separation of lanthanide ions by paper electrophoresis and magneto-paper electrophoresis is reported. The separation of La(III)-Gd(III), La(III)-Dy(III), Lu(III)-Gd(III), Lu(III)-Ho(III) etc. was achieved by magneto paper electrophoresis using 0.1M KCl as carrier electrolyte. Separation of different oxidation states of the same element like Cu(I)-Cu(II), Ce(III)-Ce(IV), Mn(CN) 6 3 - -Mn(CN) 6 4 - , Co(C 2 O 4 ) 2 2 - -Co(C 2 O 4 ) 3 3 - , V(CN) 6 3 - -VO(CN) 5 3 - , W(CN) 8 4 - -W(CN) 8 3 - and Ru(CN) 6 3 - Ru(CN) 6 4 - was also achieved by magneto paper electrophoretic technique using different carrier electrolytes. (Author)

One-Dimensional Burn Dynamics of Plasma-Jet Magneto-Inertial Fusion

Science.gov (United States)

Santarius, John

2009-11-01

This poster will discuss several issues related to using plasma jets to implode a Magneto-Inertial Fusion (MIF) liner onto a magnetized plasmoid and compress it to fusion-relevant temperatures [1]. The problem of pure plasma jet convergence and compression without a target present will be investigated. Cases with a target present will explore how well the liner's inertia provides transient plasma stability and confinement. The investigation uses UW's 1-D Lagrangian radiation-hydrodynamics code, BUCKY, which solves single-fluid equations of motion with ion-electron interactions, PdV work, table-lookup equations of state, fast-ion energy deposition, and pressure contributions from all species. Extensions to the code include magnetic field evolution as the plasmoid compresses plus dependence of the thermal conductivity and fusion product energy deposition on the magnetic field.[4pt] [1] Y.C. F. Thio, et al.,``Magnetized Target Fusion in a Spheroidal Geometry with Standoff Drivers,'' in Current Trends in International Fusion Research, E. Panarella, ed. (National Research Council of Canada, Ottawa, Canada, 1999), p. 113.

The development of small-hydro in China; Le developpement de la petite hydraulique en Chine

Energy Technology Data Exchange (ETDEWEB)

Zhu, X. [United Nations Environment Programme, Riso (Denmark); Pan, J. [Chinese Academy of Social Sciences (China). Research Centre for Economic Development

2007-04-15

Small hydro is a renewable source of energy that is economically and technically viable. This article described China's investment in small-scale hydroelectric power plants in 1,600 remote communities. Seventy per cent of China's small hydro power stations are concentrated in remote impoverished communities. These power stations provide electricity to 300 million people in China, where half of the territories, one third of the districts and towns, and one quarter of the population depend primarily on this energy source for their electricity needs. The first power station was built in the province of Yunnan in 1912, but the real development of small hydro occurred after 1950, and can be divided into three phases. Phase 1 occurred before 1980 when small hydro power stations concentrated on providing electricity for lighting in rural areas as well as for transforming agriculture and irrigation. For many decades following the foundation of the Republic of China, rural areas did not have access to electricity or had serious shortages of electricity. In order to ensure electricity in isolated and remote areas, the Chinese government requested that local authorities build and exploit small hydro where conditions were favourable, and this while respecting water resources. Phase 2 occurred between 1980s and 1990s, with a focus on improving the performance of small hydro power stations to include electricity provisions for local enterprises. During phase 2, small hydro became a tool for dynamic rural development for farmers to increase their revenues. The latest phase in small hydro development has also helped reduce poverty and develop local economies, but in addition, it plays a role in the long term protection of ecosystems, the environment and rural modernization. Today 660,000 people work for small power stations and most are employed locally. Replacing firewood with electricity has saved 130,000 hectares of forested land and helped protect ecosystems. Small

Influence of the linear magneto-electric effect on the lateral shift of light reflected from a magneto-electric film

International Nuclear Information System (INIS)

Dadoenkova, Yu S; Petrov, R V; Bichurin, M I; Bentivegna, F F L; Dadoenkova, N N; Lyubchanskii, I L

2016-01-01

We present a theoretical investigation of the lateral shift of an infrared light beam reflected from a magnetic film deposited on a non-magnetic dielectric substrate, taking into account the linear magneto-electric interaction in the magnetic film. We use the stationary phase method to evaluate the lateral shift. It is shown that the magneto-electric coupling leads to a six-fold enhancement of the lateral shift amplitude of a p-(s-) polarized incident beam reflected into a s-(p-) polarized beam. A reversal of the magnetization in the film leads to a nonreciprocal sign change of the lateral shift. (paper)

Dynamic Floodplain representation in hydrologic flood forecasting using WRF-Hydro modeling framework

Science.gov (United States)

Gangodagamage, C.; Li, Z.; Maitaria, K.; Islam, M.; Ito, T.; Dhondia, J.

2016-12-01

Floods claim more lives and damage more property than any other category of natural disaster in the Continental United States. A system that can demarcate local flood boundaries dynamically could help flood prone communities prepare for and even prevent from catastrophic flood events. Lateral distance from the centerline of the river to the right and left floodplains for the water levels coming out of the models at each grid location have not been properly integrated with the national hydrography dataset (NHDPlus). The NHDPlus dataset represents the stream network with feature classes such as rivers, tributaries, canals, lakes, ponds, dams, coastlines, and stream gages. The NHDPlus dataset consists of approximately 2.7 million river reaches defining how surface water drains to the ocean. These river reaches have upstream and downstream nodes and basic parameters such as flow direction, drainage area, reach slope etc. We modified an existing algorithm (Gangodagamage et al., 2007) to provide lateral distance from the centerline of the river to the right and left floodplains for the flows simulated by models. Previous work produced floodplain boundaries for static river stages (i.e. 3D metric: distance along the main stem, flow depth, lateral distance from river center line). Our new approach introduces the floodplain boundary for variable water levels at each reach with the fourth dimension, time. We use modeled flows from WRF-Hydro and demarcate the right and left lateral boundaries of inundation dynamically by appropriately mapping discharges into hydraulically corrected stages. Backwater effects from the mainstem to tributaries are considered and proper corrections are applied for the tributary inundations. We obtained river stages by optimizing reach level channel parameters using newly developed stream flow routing algorithm. Non uniform inundations are mapped at each NHDplus reach (upstream and downstream nodes) and spatial interpolation is carried out on a

Magneto-optic studies of magnetic oxides

International Nuclear Information System (INIS)

Gehring, Gillian A.; Alshammari, Marzook S.; Score, David S.; Neal, James R.; Mokhtari, Abbas; Fox, A. Mark

2012-01-01

A brief review of the use of magneto-optic methods to study magnetic oxides is given. A simple method to obtain the magnetic circular dichroism (MCD) of a thin film on a transparent substrate is described. The method takes full account of multiple reflections in the film and substrate. Examples of the magneto-optic spectra of Co-doped ZnO, Fe 3 O 4 , and GdMnO 3 are given. The Maxwell–Garnett method is used to describe the effects of metallic cobalt inclusions in Co:ZnO samples, and the change of the MCD spectra of Fe 3 O 4 at the Verwey temperature is discussed. Data showing different MCD signals at different energies is presented for GdMnO 3 .

Ontario Hydro CANDU operating experience

International Nuclear Information System (INIS)

Bartholomew, R.W.; Woodhead, L.W.; Horton, E.P.; Nichols, M.J.; Daly, I.N.

1987-01-01

The CANDU Pressurized Heavy Water (CANDU-PHW) type of nuclear-electric generating station has been developed jointly by Atomic Energy of Canada Limited and Ontario Hydro. This report highlights Ontario Hydro's operating experience using the CANDU-PHW system, with a focus on worker and public safety, operating performance and costs, and reliability of system components

Nonlinear modeling and stability analysis of hydro-turbine governing system with sloping ceiling tailrace tunnel under load disturbance

International Nuclear Information System (INIS)

Guo, Wencheng; Yang, Jiandong; Wang, Mingjiang; Lai, Xu

2015-01-01

Highlights: • Novel nonlinear mathematical model of hydro-turbine governing system is proposed. • Hopf bifurcation analysis on the governing system is conducted. • Stability of the system under load disturbance is studied. • Influence of four factors on stability is analyzed. • Optimization methods of improving system stability are put forward. - Abstract: In order to overcome the problem of nonlinear dynamics of hydro-turbine governing system with sloping ceiling tailrace tunnel, which is caused by the interface movement of the free surface-pressurized flow in the tailrace tunnel, and the difficulty of analyzing the stability of system, this paper uses the Hopf bifurcation theory to study the stability of hydro-turbine governing system of hydropower station with sloping ceiling tailrace tunnel. Firstly, a novel and rational nonlinear mathematical model of the hydro-turbine governing system is proposed. This model contains the dynamic equation of pipeline system which can accurately describe the motion characteristics of the interface of free surface-pressurized flow in sloping ceiling tailrace tunnel. According to the nonlinear mathematical model, the existence and direction of Hopf bifurcation of the nonlinear dynamic system are analyzed. Furthermore, the algebraic criterion of the occurrence of Hopf bifurcation is derived. Then the stability domain and bifurcation diagram of hydro-turbine governing system are drawn by the algebraic criterion, and the characteristics of stability under different state parameters are investigated. Finally, the influence of step load value, ceiling slope angle and section form of tailrace tunnel and water depth at the interface in tailrace tunnel on stability are analyzed based on stable domain. The results indicate that: The Hopf bifurcation of hydro-turbine governing system with sloping ceiling tailrace tunnel is supercritical. The phase space trajectories of characteristic variables stabilize at the equilibrium points

Curvature effect on tearing modes in presence of neoclassical friction

Energy Technology Data Exchange (ETDEWEB)

Maget, Patrick; Mellet, Nicolas; Meshcheriakov, Dmytro; Garbet, Xavier [CEA, IRFM, F-13108 Saint Paul-lez-Durance (France); Lütjens, Hinrich [Centre de Physique Théorique, Ecole Polytechnique, CNRS (France)

2013-11-15

Neoclassical physics (here associated to the poloidal variation of the magnetic field strength along field lines in a tokamak) is well known for driving self-generated plasma current and nonlinear magnetic islands associated to it in high performance, ITER relevant plasma discharges. It is demonstrated that the neoclassical friction between a magnetic perturbation and plasma flow already impacts magnetic islands in the linear regime, by inducing a weakening of curvature stabilization for tearing modes. This conclusion holds in particular for regimes where convection is influencing the pressure dynamics, as shown using a simple analytical model and confirmed in full Magneto-Hydro-Dynamics simulations.

Magneto-thermal-acoustic differential-frequency imaging of magnetic nanoparticle with magnetic spatial localization: a theoretical prediction

Science.gov (United States)

Piao, Daqing

2017-02-01

The magneto-thermo-acoustic effect that we predicted in 2013 refers to the generation of acoustic-pressure wave from magnetic nanoparticle (MNP) when thermally mediated under an alternating magnetic field (AMF) at a pulsed or frequency-chirped application. Several independent experimental studies have since validated magneto-thermoacoustic effect, and a latest report has discovered acoustic-wave generation from MNP at the second-harmonic frequency of the AMF when operating continuously. We propose that applying two AMFs with differing frequencies to MNP will produce acoustic-pressure wave at the summation and difference of the two frequencies, in addition to the two second-harmonic frequencies. Analysis of the specific absorption dynamics of the MNP when exposed to two AMFs of differing frequencies has shown some interesting patterns of acoustic-intensity at the multiple frequency components. The ratio of the acoustic-intensity at the summation-frequency over that of the difference-frequency is determined by the frequency-ratio of the two AMFs, but remains independent of the AMF strengths. The ratio of the acoustic-intensity at the summation- or difference-frequency over that at each of the two second-harmonic frequencies is determined by both the frequency-ratio and the field-strength-ratio of the two AMFs. The results indicate a potential strategy for localization of the source of a continuous-wave magneto-thermalacoustic signal by examining the frequency spectrum of full-field non-differentiating acoustic detection, with the field-strength ratio changed continuously at a fixed frequency-ratio. The practicalities and challenges of this magnetic spatial localization approach for magneto-thermo-acoustic imaging using a simple envisioned set of two AMFs arranged in parallel to each other are discussed.

Home and away with Norwegian hydro

International Nuclear Information System (INIS)

Jones, Simon

2000-01-01

Evidence of Norway's position as a world leader in terms of design and construction of hydroelectric power plant, and its position as the biggest producer of hydro in Europe, is presented. There is still some 30 TWh of hydro available for development in Norway. Statkraft is the country's biggest hydro generator: it owns and operates 54 hydro plants and has shares in a further 30. Statkraft's research has shown that there is still a large market for renewables in Europe and believes that householders are prepared to pay a premium for green energy. Statkraft trades energy with Denmark and Sweden and is believed to be planning further growth overseas. The new millennium is set to bring major changes in Norway's power industry: Hafslund and Elkem have already agreed to merge to create the country's biggest privately-owned power group

Sinkhole investigated at B.C. Hydro`s Bennett Dam

Energy Technology Data Exchange (ETDEWEB)

Anon.

1996-07-01

The cause of a sinkhole which appeared in a roadway crossing an earth filled dam in B. C., was discussed. The hole measured 6 ft. across and 20 ft. deep, and occurred in B.C. Hydro`s W.A.C. Bennett Dam which measures 600 ft. high, 2,600 ft. wide at the base and 35 ft. wide at the crest. The cause of the sinkhole is not known, but it is believed that a weakness in the dam may have found its way to the surface via a pipe connected to a bedrock settlement gauge buried within the dam. Sonar and ground penetrating radar were used to examine the area. The hole has been filled with gravel and monitoring continues. Experts do not anticipate immediate risk of dam failure. 1 fig.

Low head hydro market assessment : main report : vol. 1

International Nuclear Information System (INIS)

2008-03-01

Hydroelectric power is a predictable renewable energy source that produces no greenhouse gases (GHGs) and has low maintenance costs. In addition to river resources, low head hydro is available in sluice gates, irrigation canals, drinking water pressure release valves, and municipal wastewater outfalls. Canada's potential for low head hydro has been estimated at 5000 MW at 2000 different sites across the country. Sites of up to 50 MW have been identified in Ontario and Manitoba. This study performed a market assessment on low head hydro developments. Available and emerging technologies for developing low head hydro were identified. The economics of low head hydro in Canada were explored, and barriers to low head hydro development were identified. Strategies to promote low head hydro development were also explored, and the impact of different incentive types on the low head hydropower market were estimated using a simple economic model. It was concluded that a reduced, streamlined, and standardized environmental assessment process will significantly benefit low head hydro development in Canada. 5 refs., 14 tabs., 17 figs

Romanian achievement in hydro-power plants

International Nuclear Information System (INIS)

Cardu, M.; Bara, T.

1998-01-01

This paper briefly deals with the achievements relating to Hydro-electric Power Plants within the process of development of the National Power System in Romania. Also presented is the Romanian industry contribution to hydro-electrical power plant equipment manufacturing. (author)

Ekstraksi Minyak Atsiri Dari Akar Wangi Menggunakan Metode Steam - Hydro distillation dan Hydro distilation dengan Pemanas Microwave

Directory of Open Access Journals (Sweden)

Maulana M Al Hanief

2013-09-01

Full Text Available Penelitian ini bertujuan untuk memperoleh minyak atsiri dari akar wangi dengan modifikasi metode steam-hydro distillation dan hydro distillation yaitu menggunakan pemanasan microwave kemudian membandingkan hasilnya dengan penelitian sebelumnya. Modifikasi ini diharapkan lebih efisien dalam masalah lama penyulingan dan kualitas serta kuantitas rendemen minyak yang lebih baik dan banyak. Penelitian ini menggunakan dua metode yaitu steam-hydro distillation dan hydro distillation dengan pemanfaatan gelombang mikro. Bahan baku yang digunakan dalam penelitian adalah akar wangi jenis pulus wangi yang tumbuh di Kabupaten Garut, Jawa Barat. Variabel yang digunakan adalah bahan baku yang dicacah dan bahan baku utuh dengan variasi massa bahan 50 gr, 60, gr, 70 gr, 80 gr, dan 90 gr dengan pelarut air sebanyak 450 ml dalam labau distiller berukuran 1000 ml. Lama penyulingan adalah lima jam dengan pengamatan tiap 30 menit serta daya yang digunakan adalah 400 Watt. Analisa terhadap hasil minyak atsiri yang diperoleh antara lain analisa GC-MS, spesific gravity, indeks bias, dan bilangan asam. Hasil dari penelitian ini dibandingkan dengan hasil penelitian terdahulu yang tidak memanfaatkan gelombang mikro. Dari hasil penelitian diperoleh % rendemen kumulatif, sifat fisik, sifat kimia, dan kandungan komponen minyak dari metode steam-hydro distillation lebih baik dibandingkan metode hydro distillation ditandai dengan kuantitas dan kualitas yang sesuai dengan SNI.  Sementara itu jika dibandingkan dengan metode terdahulu dapat disimpulkan bahwa penggunaan gelombang mikro lebih efisien dalam waktu dan kuantitas serta kualitas minyak yang lebih baik dibandingkan tanpa penggunaan gelombang mikro

Development of magneto-plasmonic nanoparticles for multimodal image-guided therapy to the brain

OpenAIRE

Tomitaka, Asahi; Arami, Hamed; Raymond, Andrea; Yndart, Adriana; Kaushik, Ajeet; Jayant, Rahul Dev; Takemura, Yasushi; Cai, Yong; Toborek, Michal; Nair, Madhavan

2017-01-01

Magneto-plasmonic nanoparticles are one of the emerging multi-functional materials in the field of nanomedicine. Their potential for targeting and multi-modal imaging is highly attractive. In this study, magnetic core / gold shell (MNP@Au) magneto-plasmonic nanoparticles were synthesized by citrate reduction of Au ion on magnetic nanoparticle seeds. Hydrodynamic size and optical property of magneto-plasmonic nanoparticles synthesized with the variation of Au ion and reducing agent concentrati...

Hydro-Quebec looks south

International Nuclear Information System (INIS)

Ross, P.

1997-01-01

The recent introduction of Hydro-Quebec, the Canadian utility, into selling cheap electric power in the United States (US) deregulated power market is described, following applications to the US Federal Energy Regulatory Commission. As its prices are so much cheaper than its US competitors, it is expected that the company will soon have many willing customers across the USA. Hydro-Quebec will remain a publicly owned utility, but has experienced restructuring in order to meet this new competitive challenge. (UK)

Hydro-Quebec is profitable

International Nuclear Information System (INIS)

Poirier, M.

1997-01-01

The pros and cons of the potential privatisation of Hydro-Quebec were discussed. A brief review of charges of less than competent management, low profitability and the corporation's recent administrative restructuring was presented. The general thrust of the argument was that Hydro-Quebec plays a crucial role in the economic development of Quebec, it can be made to be more profitable and that for the good of Quebec it should continue as a public corporation under the control of the provincial government

The influence of platinum washing-out time on its recovery from used auto catalytic converters

Directory of Open Access Journals (Sweden)

A. Fornalczyk

2014-07-01

Full Text Available The used catalytic converters contain small amounts of precious metals. Recovery of these metals is essential for environmental and economic reasons. This work presents a method of Platinum Group Metals (PGM recovery from auto catalytic converters in which they are washed out by a liquid metal. The magneto-hydro-dynamic pump was used to force circulation of liquid metal under the influence of electromagnetic fields The influence of process time on platinum recovery was also carried out.

Méthodes numériques pour les plasmas sur architectures multicoeurs

OpenAIRE

Massaro , Michel

2016-01-01

This thesis deals with the resolution of the Magneto-Hydro-Dynamic (MHD) system on massively parallel architectures. This problem is an hyperbolic system of conservation laws. For cost reasons in terms of time and space, we use the finite volume method. These criteria are particularly important in the case of MHD because the solutions obtained may have many shock waves and be very turbulent. The approach of a physical phenomenon requires working on a fine mesh which involves a large quantity ...

Ontario Hydro CANDU operating experience

International Nuclear Information System (INIS)

Jackson, H.A.; Woodhead, L.W.; Fanjoy, G.R.

1984-03-01

The CANDU Pressurized Heavy Water (CANDU-PHW) type of nuclear-electric generating station has been developed jointly by Atomic Energy of Canada Limited and Ontario Hydro. This report highlights Ontario Hydro's operating experience using the CANDU-PHW system, with a focus on the operating performance and costs, reliability of system components and nuclear safety considerations for the workers and the public

Small steps for hydro

International Nuclear Information System (INIS)

Wicke, Peter

1998-01-01

The government in Peru has decided to utilise its gas reserves and restrict hydro to relatively small schemes. A number of reasons for the decision are given. In 1997, the Shell-Mobile-Bechtel-COSAPI consortium was formed and agreements were signed regarding exploiting Gas de Camisea. The country's energy needs to 2010 are being assessed. It is likely that by 2001 the whole of south Peru will be receiving gas from Camisea. The Peru situation is discussed under the headings of (i) existing capacity, (ii) growing demands, (iii) a history of hydro in Peru, (iv) electrification and SHP and (v) outlook. The future for Peru's electric energy development is bright. While most of its new power capacity will come from natural gas, the small hydros also have a part to play. A stronger commitment of national and regional political authorities to consider supplies outside the big cities is said to be needed. (UK)

Magneto-optic studies of magnetic oxides

Energy Technology Data Exchange (ETDEWEB)

Gehring, Gillian A., E-mail: g.gehring@shef.ac.uk [Department of Physics and Astronomy, University of Sheffield, Sheffield S3 7RH (United Kingdom); Alshammari, Marzook S.; Score, David S.; Neal, James R.; Mokhtari, Abbas; Fox, A. Mark [Department of Physics and Astronomy, University of Sheffield, Sheffield S3 7RH (United Kingdom)

2012-10-15

A brief review of the use of magneto-optic methods to study magnetic oxides is given. A simple method to obtain the magnetic circular dichroism (MCD) of a thin film on a transparent substrate is described. The method takes full account of multiple reflections in the film and substrate. Examples of the magneto-optic spectra of Co-doped ZnO, Fe{sub 3}O{sub 4}, and GdMnO{sub 3} are given. The Maxwell-Garnett method is used to describe the effects of metallic cobalt inclusions in Co:ZnO samples, and the change of the MCD spectra of Fe{sub 3}O{sub 4} at the Verwey temperature is discussed. Data showing different MCD signals at different energies is presented for GdMnO{sub 3}.

Modeling invasive alien plant species in river systems: Interaction with native ecosystem engineers and effects on hydro-morphodynamic processes

Science.gov (United States)

van Oorschot, M.; Kleinhans, M. G.; Geerling, G. W.; Egger, G.; Leuven, R. S. E. W.; Middelkoop, H.

2017-08-01

Invasive alien plant species negatively impact native plant communities by out-competing species or changing abiotic and biotic conditions in their introduced range. River systems are especially vulnerable to biological invasions, because waterways can function as invasion corridors. Understanding interactions of invasive and native species and their combined effects on river dynamics is essential for developing cost-effective management strategies. However, numerical models for simulating long-term effects of these processes are lacking. This paper investigates how an invasive alien plant species affects native riparian vegetation and hydro-morphodynamics. A morphodynamic model has been coupled to a dynamic vegetation model that predicts establishment, growth and mortality of riparian trees. We introduced an invasive alien species with life-history traits based on Japanese Knotweed (Fallopia japonica), and investigated effects of low- and high propagule pressure on invasion speed, native vegetation and hydro-morphodynamic processes. Results show that high propagule pressure leads to a decline in native species cover due to competition and the creation of unfavorable native colonization sites. With low propagule pressure the invader facilitates native seedling survival by creating favorable hydro-morphodynamic conditions at colonization sites. With high invader abundance, water levels are raised and sediment transport is reduced during the growing season. In winter, when the above-ground invader biomass is gone, results are reversed and the floodplain is more prone to erosion. Invasion effects thus depend on seasonal above- and below ground dynamic vegetation properties and persistence of the invader, on the characteristics of native species it replaces, and the combined interactions with hydro-morphodynamics.

Implosion scaling and hydro dynamically equivalent target design - Strategy for proof of principle of high gain inertial fusion

International Nuclear Information System (INIS)

Murakami, M.; Nishihara, K.; Azechi, H.; Nakatsuka, M.; Kanabe, T.; Miyanaga, N.

2003-01-01

Scaling laws for hydro dynamically similar implosions are derived by applying Lie group analysis to the set of partial differential equations for the hydrodynamic system. Physically this implies that any fluid system belonging to a common similarity group evolves quite in the same manner including hydrodynamic instabilities. The scalings strongly depend on the description of the energy transport, i.e., whether the fluid system is heat conductive or adiabatic. Under a fully specified group transformation including prescriptions on the laser wavelength and the ionization state, the hydrodynamic similarity can still be preserved even when the system is cooperated with such other energy sources as classical laser absorption, hot electrons, local alpha heating, and bremsstrahlung loss. The results are expected to give the basis of target design and diagnostics for scaled high gain experiments in future. (author)

Hydro power flexibility for power systems with variable renewable energy sources: an IEA Task 25 collaboration: Hydro power flexibility for power systems

Energy Technology Data Exchange (ETDEWEB)

Huertas-Hernando, Daniel [Department of Energy Systems, SINTEF, Trondheim Norway; Farahmand, Hossein [Department of Electric Power Engineering, Norwegian University of Science and Technology (NTNU), Trondheim Norway; Holttinen, Hannele [Department of Energy Systems, VTT Technical Research Centre of Finland, Espoo Finland; Kiviluoma, Juha [Department of Energy Systems, VTT Technical Research Centre of Finland, Espoo Finland; Rinne, Erkka [Department of Energy Systems, VTT Technical Research Centre of Finland, Espoo Finland; Söder, Lennart [Department of Electrical Engineering, KTH University, Stockholm Sweden; Milligan, Michael [Transmission and Grid Integration Group, National Renewable Energy Laboratory' s National Wind Technology Center, Golden CO USA; Ibanez, Eduardo [Transmission and Grid Integration Group, National Renewable Energy Laboratory' s National Wind Technology Center, Golden CO USA; Martínez, Sergio Martín [Department of Electrical Engineering, Electronics, Automation and Communications, Universidad de Castilla-La Mancha, Albacete Spain; Gomez-Lazaro, Emilio [Department of Electrical Engineering, Electronics, Automation and Communications, Universidad de Castilla-La Mancha, Albacete Spain; Estanqueiro, Ana [National Laboratory of Energy and Geology - LNEG, Lisbon Portugal; Rodrigues, Luis [National Laboratory of Energy and Geology - LNEG, Lisbon Portugal; Carr, Luis [Research Association for Energy Economics (FfE GmbH), Munich Germany; van Roon, Serafin [Research Association for Energy Economics (FfE GmbH), Munich Germany; Orths, Antje Gesa [Energinet.dk, Fredericia Denmark; Eriksen, Peter Børre [Energinet.dk, Fredericia Denmark; Forcione, Alain [Hydro Quebec, Montréal Canada; Menemenlis, Nickie [Hydro Quebec, Montréal Canada

2016-06-20

Hydro power is one of the most flexible sources of electricity production. Power systems with considerable amounts of flexible hydro power potentially offer easier integration of variable generation, e.g., wind and solar. However, there exist operational constraints to ensure mid-/long-term security of supply while keeping river flows and reservoirs levels within permitted limits. In order to properly assess the effective available hydro power flexibility and its value for storage, a detailed assessment of hydro power is essential. Due to the inherent uncertainty of the weather-dependent hydrological cycle, regulation constraints on the hydro system, and uncertainty of internal load as well as variable generation (wind and solar), this assessment is complex. Hence, it requires proper modeling of all the underlying interactions between hydro power and the power system, with a large share of other variable renewables. A summary of existing experience of wind integration in hydro-dominated power systems clearly points to strict simulation methodologies. Recommendations include requirements for techno-economic models to correctly assess strategies for hydro power and pumped storage dispatch. These models are based not only on seasonal water inflow variations but also on variable generation, and all these are in time horizons from very short term up to multiple years, depending on the studied system. Another important recommendation is to include a geographically detailed description of hydro power systems, rivers' flows, and reservoirs as well as grid topology and congestion.

Grid Compatibility of Variable Speed Wind Turbines with Directly Coupled Synchronous Generator and Hydro-Dynamically Controlled Gearbox

Energy Technology Data Exchange (ETDEWEB)

Mueller, H.; Poeller, M. [DIgSILENT GmbH, 72810 Gomaringen (Germany); Basteck, A.; Tilscher, M.; Pfister, J. [Voith Turbo GmbH and Co. KG, 74564 Crailsheim (Germany)

2006-07-01

This paper analyzes grid integration aspects of a new type of variable-speed wind turbine, the directly coupled synchronous generator with hydro-dynamically controlled gearbox. In contrast to existing wind generators using synchronous generators, the generator of this concept is directly connected to the AC grid, without the application of any power electronics converter. Variable speed operation of the turbine is mechanically achieved by a gear box with continuously controllable variable gear box ratio. For this purpose, a detailed dynamic model of a 2 MW wind turbine with a Voith WinDrive has been implemented using the modelling environment of the simulation software DIgSILENT PowerFactory. For investigating grid compatibility aspects of this new wind generator concept, a model of a 50 MW wind farm, with typical layout, based on 25 wind turbines of the 2 MW-class has been analyzed. This paper focuses on the compatibility of the new concept with existing connection standards, such as the E.ON grid code. Of special interest are typical stability phenomena of synchronous generators, such as transient and oscillatory stability as well as power quality issues like voltage flicker. The results of stability studies are presented and possible advantages of the new concept with special focus on offshore applications are discussed.

Giant magneto-impedance effect on nanocrystalline microwires with conductive layer deposit

International Nuclear Information System (INIS)

Wang, R.L.; Zhao, Z.J.; Liu, L.P.; Yuan, W.Z.; Yang, X.L.

2005-01-01

In this study, the giant magneto-impedance effect on Fe-based glass-coated nanocrystalline microwires with and without an additional outer copper layer was investigated. Experiment results showed that the magneto-impedance ratio of the wires with a layer of deposited copper is higher at low frequencies and lower at high frequencies (above 50 MHz), as compared to that of the microwires without an outer copper layer. The peak MI magnetic field, corresponding to the maximum of the magneto-impedance ratio shifts towards higher field values with increasing coating thickness of copper layer. The results are explained in terms of electro-magnetic interactions between the conductive layer and the ferromagnetic core

Hydro investment analysis under new market conditions

Energy Technology Data Exchange (ETDEWEB)

Doorman, Gerard

2010-07-01

of new capacity. Several approaches will be considered and evaluated, among these: Development of EOPS-ST. This model combines long term stochastic optimization with a more detailed short term model that uses linear programming; Development of ProdRisk, which is based on Stochastic Dual Dynamic Programming (SDDP) that allows for more detailed modelling than the traditional SDP approach; A new method using simulator based hydro scheduling models, where first stage decisions are based on deterministic equivalents. A model of this type has been tested for the hydro thermal market problem with good results, but so far without the necessary level of detail. As a first step these approaches will be compared with respect to their potential to solve the actual tasks. The next step will be to implement necessary extensions in the most promising model. In the final phase, the enhanced model will be used for relevant analyses like capacity increases in existing plants, pumped storage, the effect of constraints etc. The presentation will include relevant examples of the impact of higher daily price variations on the operation of the Sira Kvina system. (Author)

Regularity criteria for the 3D magneto-micropolar fluid equations via ...

Indian Academy of Sciences (India)

3D magneto-micropolar fluid equations. It involves only the direction of the velocity and the magnetic field. Our result extends to the cases of Navier–Stokes and MHD equations. Keywords. Magneto-micropolar fluid equations; regularity criteria; direction of velocity. 2010 Mathematics Subject Classification. 35Q35, 76W05 ...

The transverse shear deformation behaviour of magneto-electro-elastic shell

International Nuclear Information System (INIS)

Albarody, Thar M. Badri; Al-Kayiem, Hussain H.; Faris, Waleed

2016-01-01

Compared to the large number of possible magneto-electro-elastic shell theories, very few exact solutions determining the in-plane stresses, electric displacements and magnetic inductions are possible. While, solving the magneto-electro-elastic shell equations in terms of thermo-magneto-electro-elastic generalized field functions on arbitrary domains and for general conditions exactly are not always possible. In the present work, a linear version of magneto-electro-elastic shell with simply supported boundary conditions, solved exactly, provided that the lamination scheme is cross-ply or anti-symmetric angle-ply laminates. The exact solution that introduced herein can measure the in-plane stresses, electric displacements and magnetic inductions. It also allow for an accurate and usually elegant and conclusive investigation of the various sensations in a shell structure. However, it is important for micro-electro-mechanical shell applications to have an approach available that gives the transverse shear deformation Behaviour for cases that cannot examine experimentally. An investigated examples were accompanied and noteworthy conclusions were drawn which highlight the issues of the implementation of the exact solution, implication of the effects of the material properties, lay-ups of the constituent layers, and shell parameters on the static Behaviour

The transverse shear deformation behaviour of magneto-electro-elastic shell

Energy Technology Data Exchange (ETDEWEB)

Albarody, Thar M. Badri; Al-Kayiem, Hussain H. [UniversitiTeknologi PETRONAS, Perak (Malaysia); Faris, Waleed [International Islamic University Malaysia, Perak (Malaysia)

2016-01-15

Compared to the large number of possible magneto-electro-elastic shell theories, very few exact solutions determining the in-plane stresses, electric displacements and magnetic inductions are possible. While, solving the magneto-electro-elastic shell equations in terms of thermo-magneto-electro-elastic generalized field functions on arbitrary domains and for general conditions exactly are not always possible. In the present work, a linear version of magneto-electro-elastic shell with simply supported boundary conditions, solved exactly, provided that the lamination scheme is cross-ply or anti-symmetric angle-ply laminates. The exact solution that introduced herein can measure the in-plane stresses, electric displacements and magnetic inductions. It also allow for an accurate and usually elegant and conclusive investigation of the various sensations in a shell structure. However, it is important for micro-electro-mechanical shell applications to have an approach available that gives the transverse shear deformation Behaviour for cases that cannot examine experimentally. An investigated examples were accompanied and noteworthy conclusions were drawn which highlight the issues of the implementation of the exact solution, implication of the effects of the material properties, lay-ups of the constituent layers, and shell parameters on the static Behaviour.

Hydro or the waltz of managers

International Nuclear Information System (INIS)

Anon.

1997-01-01

A critique of current management and personnel problems at Hydro-Quebec was presented. With 20,000 employees and some of the world's greatest hydroelectric projects to its credit, Hydro-Quebec has historically been a source of great pride for its employees and Quebec's society. However, recent problems related to management, bureaucratization and communications within the corporation have led to important moral problems within the workforce. Management of the corporation under the newly appointed president, Andre Caille, the issue of profitability and competitiveness, the worsening morale among employees and the relationship between Hydro-Quebec and the provincial government were the principal topics discussed

Innovative private micro-hydro power development in Rwanda

International Nuclear Information System (INIS)

Pigaht, Maurice; Plas, Robert J. van der

2009-01-01

Under the 'Private Sector Participation in Micro-Hydro Development Project in Rwanda', four newly registered Rwandan companies are each constructing a micro-hydro electricity plant (100-500 kW) and building a low-voltage distribution grid. These companies financed their plants through their own equity and debt with support from the PSP Hydro project. This support comprised a subsidy of 30-50% of investment costs, technical and business development assistance, project monitoring and financial controlling. The experiences gained so far have important implications for similar future micro-hydro energy sector development projects and this paper puts forward three key messages: (i) institutional arrangements rather than technical quality determine the success of such projects; (ii) truly sustainable rural electrification through micro-hydro development demands a high level of local participation at all levels and throughout all project phases, not just after plant commissioning; and (iii) real impact and sustainability can be obtained through close collaboration of local private and financial sector firms requiring only limited external funds. In short, micro-hydro projects can and will be taken up by local investors as a business if the conditions are right. Applying these messages could result in an accelerated uptake of viable micro-hydro activities in Rwanda, and in the opinion of the authors elsewhere too.

Effective-mass model and magneto-optical properties in hybrid perovskites

OpenAIRE

Yu, Z. G.

2016-01-01

Hybrid inorganic-organic perovskites have proven to be a revolutionary material for low-cost photovoltaic applications. They also exhibit many other interesting properties, including giant Rashba splitting, large-radius Wannier excitons, and novel magneto-optical effects. Understanding these properties as well as the detailed mechanism of photovoltaics requires a reliable and accessible electronic structure, on which models of transport, excitonic, and magneto-optical properties can be effici...

Hydro-Quebec 2005 annual report : people with energy

International Nuclear Information System (INIS)

2006-01-01

Hydro-Quebec generates, transmits and distributes electricity mainly produced by renewable energy sources. Its sole shareholder is the Quebec government. This annual report reviewed the operations of Hydro-Quebec, and provided data on energy sales, production and details of the utility's environmental programs. Information on Hydro-Quebec subsidiaries in 2005 was presented in the following separate sections: Hydro-Quebec Production; Hydro-Quebec TransEnergie; Hydro-Quebec Distribution; Hydro-Quebec Equipement; and the Societe d'energie de la Baie James. In 2005, Hydro-Quebec Distribution signed contracts for an initial block of 990 MW of wind power and issued a tender call for an additional 2000 MW of wind power. A generator balancing service was created and authorized by the Regie de l'energie. Hydro-Quebec customers have achieved energy savings of nearly 450 GWh in 2005. The commissioning of Toulnustouc generating station was achieved 5 months ahead of schedule. The 526 MW facility will generate 2.7 TWh annually. Work at the Chute-Allard and Rapide-des-Coeurs sites has continued, as well as construction at Mercier and Peribonka and Eastmain-1. Income from continuing operations came to $2.25 billion, a $124 million increase that was attributed to a rise in domestic sales and net short-term exports. The income was offset by higher pension expenses, depreciation and amortization, as well as by cost of supply on external markets and financial expenses. All other operating expenses were lower than in 2004. Capital spending for the transmission system reached its highest level since 1997, with $793 million invested, including $336 million to meet growth. Data on the company's financial performance, executive changes and reorganization were provided. Financial statements included a review and analysis of financial transactions, an auditor's report, as well as customary notes to the consolidated financial statement including balance sheets, assets, liabilities and

Experimental study of the anisotropic magneto-Seebeck effect in (Ga,Mn)As thin films

Energy Technology Data Exchange (ETDEWEB)

Althammer, Matthias; Krupp, Alexander T.; Brenninger, Thomas; Venkateshvaran, Deepak; Opel, Matthias; Gross, Rudolf; Goennenwein, Sebastian T.B. [Walther-Meissner-Institut, Bayerische Akademie der Wissenschaften, Garching (Germany); Dreher, Lukas [Walter Schottky Institut, Technische Universitaet Muenchen, Garching (Germany); Schoch, Wladimir; Limmer, Wolfgang [Abteilung Halbleiterphysik, Universitaet Ulm, Ulm (Germany)

2011-07-01

In analogy to anisotropic magnetoresistance (AMR), the thermopower of ferromagnetic materials also characteristically depends on the orientation of the magnetization vector. This anisotropic magneto-thermopower - or anisotropic magneto-Seebeck effect (AMS) - has only scarcely been studied to date. Taking the ferromagnetic semiconductor (Ga,Mn)As with its large magneto-resistive effects as a prototype example, we have measured the evolution of both the AMR and the AMS effects at liquid He temperatures as a function of the orientation of a magnetic field applied in the (Ga,Mn)As film plane, for different, fixed magnetic field magnitudes. Our data show that the AMS effect can be adequately modeled only if the symmetry of the (Ga,Mn)As crystal is explicitly taken into account. We quantitatively compare our AMR and AMS measurements with corresponding model calculations, and address the validity of the Mott relations linking the magneto-resistance and the magneto-Seebeck coefficients.

Hydro-Quebec's environmental policy

International Nuclear Information System (INIS)

1996-10-01

Hydro-Quebec established a new environmental policy on August 1, 1996. A summary of the policy was presented. According to this policy statement the utility undertakes to recognize the environmental implications of its activities and assumes responsibilities for these implications by integrating them into its corporate decision-making processes. The following general principles and means of implementation have been highlighted: (1) sustainable development, (2) strict, responsible environmental management, (3) environmental research, (4) enhancement of activities and facilities, (5) information, consultation and dialogue, and (6) environmental responsibility of Hydro-Quebec personnel, subsidiaries and business partners

An analytical solution for the magneto-electro-elastic bimorph beam forced vibrations problem

International Nuclear Information System (INIS)

Milazzo, A; Orlando, C; Alaimo, A

2009-01-01

Based on the Timoshenko beam theory and on the assumption that the electric and magnetic fields can be treated as steady, since elastic waves propagate very slowly with respect to electromagnetic ones, a general analytical solution for the transient analysis of a magneto-electro-elastic bimorph beam is obtained. General magneto-electric boundary conditions can be applied on the top and bottom surfaces of the beam, allowing us to study the response of the bilayer structure to electromagnetic stimuli. The model reveals that the magneto-electric loads enter the solution as an equivalent external bending moment per unit length and as time-dependent mechanical boundary conditions through the definition of the bending moment. Moreover, the influences of the electro-mechanic, magneto-mechanic and electromagnetic coupling on the stiffness of the bimorph stem from the computation of the beam equivalent stiffness constants. Free and forced vibration analyses of both multiphase and laminated magneto-electro-elastic composite beams are carried out to check the effectiveness and reliability of the proposed analytic solution

Climate impact on BC Hydro's water resources

International Nuclear Information System (INIS)

Smith, D.; Rodenhuis, D.

2008-01-01

BC Hydro like many other hydro utilities has used the historical record of weather and runoff as the standard description the variability and uncertainty of the key weather drivers for its operation and planning studies. It has been conveniently assumed that this historical record is or has been statistically stationary and therefore is assumed to represent the future characteristics of climatic drivers on our system. This assumption is obviously no longer justifiable. To address the characterisation of future weather, BC Hydro has a multi-year a directed research program with the Pacific Climate Impacts Consortium to evaluate the impacts of climate change on the water resources that BC Hydro manages for hydropower generation and other uses. The objective of this program is to derive climate change adjusted meteorologic and hydrologic sequences suitable for use in system operations and planning studies. These climate-adjusted sequences then can be used to test system sensitivity to climate change scenarios relative to the baseline of the historical record. This paper describes BC Hydro's research program and the results achieved so far. (author)

The development of biodiversity conservation measures in China's hydro projects: A review.

Science.gov (United States)

Bai, Ruiqiao; Liu, Xuehua; Liu, Xiaofei; Liu, Lanmei; Wang, Jianping; Liao, Sihui; Zhu, Annah; Li, Zhouyuan

2017-11-01

The hydropower capacity of China ranks first in the world and accounts for approximately 20% of the total energy production in the country. While hydropower has substantially contributed to meeting China's renewable energy targets and providing clean energy to rural areas, the development of hydropower in China has been met with significant controversy. Ecologically, hydro projects alter the landscape, with potential impacts to the country's aquatic biodiversity. Over the past four decades in China, various mainstream opinions and misunderstandings have been presented concerning how to alleviate the negative impacts of hydro projects on aquatic ecosystems. This article reviews research concerning potential mitigation measures to enhance aquatic biodiversity conservation in hydro projects in China. Based on the academic attention such research has attracted, three technical measures for aquatic biodiversity conservation are considered: (1) fish passages, (2) restocking efforts and (3) river and lake renovations. This article provides a historical comparison of these three practices in China to demonstrate the advantages and disadvantages of each method. The article also reviews the relevant legislation, regulations and technical guidelines concerning China's hydro projects dating back to 1979. The dynamics in research, publications, and patents concerning these three mitigation measures are summarized to demonstrate their technological developments in the context of legislative and policy advances. Data were gathered through the China Knowledge Resource Integrated Database and the State Intellectual Property Office of the People's Republic of China. Based on the analysis provided, the article recommends an expansion of China's environmental certification system for hydro projects, more robust regional legislation to bolster the national framework, the cooperation between upstream and downstream conservation mechanisms, and better monitoring to determine the efficacy

Magneto-therapy of human joint cartilage.

Science.gov (United States)

Wierzcholski, Krzysztof; Miszczak, Andrzej

2017-01-01

The topic of the present paper concerns the human joint cartilage therapy performed by the magnetic induction field. There is proved the thesis that the applied magnetic field for concrete cartilage illness should depend on the proper relative and concrete values of applied magnetic induction, intensity as well the time of treatment duration. Additionally, very important are frequencies and amplitudes of magnetic field as well as magnetic permeability of the synovial fluid. The research methods used in this paper include: magnetic induction field produced by a new Polish and German magneto electronic devices for the therapy of human joint cartilage diseases, stationary and movable magnetic applicators, magnetic bandage, ferrofluid injections, author's experience gained in Germany research institutes and practical results after measurements and information from patients. The results of this paper concern concrete parameters of time dependent electro-magnetic field administration during the joint cartilage therapy duration and additionally concern the corollaries which are implied from reading values gained on the magnetic induction devices. The main conclusions obtained in this paper are as follows: Time dependent magnetic induction field increases the dynamic viscosity of movable synovial fluid and decreases symptoms of cartilage illness for concrete intensity of magnetic field and concrete field line architecture. The ferrofluid therapy and phospholipids bilayer simultaneously with the administrated external electromagnetic field, increases the dynamic viscosity of movable synovial fluid.

Mathematical Modelling and Parameter Identification of an Electro-Magneto-Mechanical Actuator for Vibration Control

DEFF Research Database (Denmark)

Darula, Radoslav; Stein, George Juraj; Kallesøe, Carsten Skovmose

2012-01-01

Electromechanical systems for vibration control exhibit complex non-linear behaviour. Therefore advanced mathematical tools and appropriate simplifications are required for their modelling. To properly understand the dynamics of such a non-linear system, it is necessary to identify the parameters....... The electric circuit is closed with a shunt resistance connected to the electromagnet. The current induced in the circuit generates additional alternating magnetic force. This force counteracts the original vibration and damps it. In this way the coupled electro-magneto-mechanical system suppresses the forced...

An Overview of Power Topologies for Micro-hydro Turbines

DEFF Research Database (Denmark)

Nababan, Sabar; Muljadi, E.; Blaabjerg, Frede

2012-01-01

This paper is an overview of different power topologies of micro-hydro turbines. The size of micro-hydro turbine is typically under 100kW. Conventional topologies of micro-hydro power are stand-alone operation used in rural electrical network in developing countries. Recently, many of micro-hydro...... power generations are connected to the distribution network through power electronics (PE). This turbines are operated in variable frequency operation to improve efficiency of micro-hydro power generation, improve the power quality, and ride through capability of the generation. In this paper our...... discussion is limited to the distributed generation. Like many other renewable energy sources, the objectives of micro-hydro power generation are to reduce the use of fossil fuel, to improve the reliability of the distribution system (grid), and to reduce the transmission losses. The overview described...

Broadbanding of circularly polarized patch antenna by waveguided magneto-dielectric metamaterial

Directory of Open Access Journals (Sweden)

Xin Mi Yang

2015-12-01

Full Text Available Design of bandwidth-enhanced circularly polarized (CP patch antenna using artificial magneto-dielectric substrate was investigated. The artificial magneto-dielectric material adopted here takes the form of waveguided metamaterial (WG-MTM. In particular, the embedded meander line (EML structure was employed as the building element of the WG-MTM. As verified by the retrieved effective medium parameters, the EML-based waveguided magneto-dielectric metamaterial (WG-MDM exhibits two-dimensionally isotropic magneto-dielectric property with respect to TEM wave excitations applied in two orthogonal directions. A CP patch antenna loaded with the EML-based WG-MDM (WG-MDM antenna has been proposed and its design procedure is described in detail. Simulation results show that the impedance and axial ratio bandwidths of the WG-MDM antenna have increased by 125% and 133%, respectively, compared with those obtained with pure dielectric substrate offering the same patch size. The design of the novel WG-MDM antenna was also validated by measurement results, which show good agreement with their simulated counterparts.

Rich magneto-absorption spectra of AAB-stacked trilayer graphene.

Science.gov (United States)

Do, Thi-Nga; Shih, Po-Hsin; Chang, Cheng-Peng; Lin, Chiun-Yan; Lin, Ming-Fa

2016-06-29

A generalized tight-binding model is developed to investigate the feature-rich magneto-optical properties of AAB-stacked trilayer graphene. Three intragroup and six intergroup inter-Landau-level (inter-LL) optical excitations largely enrich magneto-absorption peaks. In general, the former are much higher than the latter, depending on the phases and amplitudes of LL wavefunctions. The absorption spectra exhibit single- or twin-peak structures which are determined by quantum modes, LL energy spectra and Fermion distribution. The splitting LLs, with different localization centers (2/6 and 4/6 positions in a unit cell), can generate very distinct absorption spectra. There exist extra single peaks because of LL anti-crossings. AAB, AAA, ABA, and ABC stackings considerably differ from one another in terms of the inter-LL category, frequency, intensity, and structure of absorption peaks. The main characteristics of LL wavefunctions and energy spectra and the Fermi-Dirac function are responsible for the configuration-enriched magneto-optical spectra.

[Ontario Hydro International Inc.]. Annual report 1993

International Nuclear Information System (INIS)

1994-01-01

Ontario Hydro International Inc. is the international representative of Ontario Hydro. OHII operates as a global utility that markets Ontario Hydro's services and products. Its mission is to be the leader in energy efficiency and sustainable development in the international marketplace. This report describes the year's activities in the following areas: Energy management and environment, hydroelectric generation, nuclear products and services, fossil generation, grid (transmission) business, utility management, Asia Power Group Inc. The document also includes financial highlights and international and customer contracts

Innovative private micro-hydro power development in Rwanda

Energy Technology Data Exchange (ETDEWEB)

Pigaht, Maurice; Van der Plas, Robert J. [MARGE-Netherlands, Brem 68, 7577 EW Oldenzaal (Netherlands)

2009-11-15

Under the 'Private Sector Participation in Micro-Hydro Development Project in Rwanda', four newly registered Rwandan companies are each constructing a micro-hydro electricity plant (100-500 kW) and building a low-voltage distribution grid. These companies financed their plants through their own equity and debt with support from the PSP Hydro project. This support comprised a subsidy of 30-50% of investment costs, technical and business development assistance, project monitoring and financial controlling. The experiences gained so far have important implications for similar future micro-hydro energy sector development projects and this paper puts forward three key messages: (1) institutional arrangements rather than technical quality determine the success of such projects; (2) truly sustainable rural electrification through micro-hydro development demands a high level of local participation at all levels and throughout all project phases, not just after plant commissioning; and (3) real impact and sustainability can be obtained through close collaboration of local private and financial sector firms requiring only limited external funds. In short, micro-hydro projects can and will be taken up by local investors as a business if the conditions are right. Applying these messages could result in an accelerated uptake of viable micro-hydro activities in Rwanda, and in the opinion of the authors elsewhere too. (author)

Magneto-acoustic resonance in a non-uniform current carrying plasma column

OpenAIRE

Vaclavik, J.

2017-01-01

The forced radial magneto-acoustic oscillations in a plasma column with nonuniform mass density and temperature are investigated. It turns out that the oscillations have a resonant character similar to that of the magneto-acoustic oscillations in a uniform plasma column. The properties of the axial and azimuthal components of the oscillating magnetic field are discussed in detail

Image correction in magneto-optical microscopy

DEFF Research Database (Denmark)

Paturi, P.; Larsen, B.H.; Jacobsen, B.A.

2003-01-01

An image-processing procedure that assures correct determination of the magnetic field distribution of magneto-optical images is presented. The method remedies image faults resulting from sources that are proportional to the incident light intensity, such as different types of defects...

Himalayan hydro on the horizon

International Nuclear Information System (INIS)

Sharp, Timothy

2000-01-01

The prospects for development of hydro in the Himalayas has been enhanced by privatisation and the urgent need for clean electricity in the north of India. There are various hurdles to be overcome before the projects are likely to move forward in earnest before 2005, and these are mentioned. The demand for electricity in India is said to be enormous. At present, there is much polluting industry along the Himalayas. As throughout the Indian privatisation dilemma, the critical issues for development of Himalayan hydro come down to credible commercial power markets and finance. With regard to finance and administrative changes, the Indian government is carrying out a number of actions and these are itemised. The US is vigorously promoting the development of Himalayan hydro as a key to much needed regional co-operation and the World Bank is supportive

Plasma-Jet Magneto-Inertial Fusion Burn Calculations

Science.gov (United States)

Santarius, John

2010-11-01

Several issues exist related to using plasma jets to implode a Magneto-Inertial Fusion (MIF) liner onto a magnetized plasmoid and compress it to fusion-relevant temperatures [1]. The poster will explore how well the liner's inertia provides transient plasma confinement and affects the burn dynamics. The investigation uses the University of Wisconsin's 1-D Lagrangian radiation-hydrodynamics code, BUCKY, which solves single-fluid equations of motion with ion-electron interactions, PdV work, table-lookup equations of state, fast-ion energy deposition, pressure contributions from all species, and one or two temperatures. Extensions to the code include magnetic field evolution as the plasmoid compresses plus dependence of the thermal conductivity on the magnetic field. [4pt] [1] Y.C. F. Thio, et al.,``Magnetized Target Fusion in a Spheroidal Geometry with Standoff Drivers,'' in Current Trends in International Fusion Research, E. Panarella, ed. (National Research Council of Canada, Ottawa, Canada, 1999), p. 113.

Hydro-economic modelling in mining catchments

Science.gov (United States)

Ossa Moreno, J. S.; McIntyre, N.; Rivera, D.; Smart, J. C. R.

2017-12-01

Hydro-economic models are gaining momentum because of their capacity to model both the physical processes related to water supply, and socio-economic factors determining water demand. This is particularly valuable in the midst of the large uncertainty upon future climate conditions and social trends. Agriculture, urban uses and environmental flows have received a lot of attention from researchers, as these tend to be the main consumers of water in most catchments. Mine water demand, although very important in several small and medium-sized catchments worldwide, has received less attention and only few models have attempted to reproduce its dynamics with other users. This paper describes an on-going project that addresses this gap, by developing a hydro-economic model in the upper Aconcagua River in Chile. This is a mountain catchment with large scale mining and hydro-power users at high altitudes, and irrigation areas in a downstream valley. Relevant obstacles to the model included the lack of input climate data, which is a common feature in several mining areas, the complex hydrological processes in the area and the difficulty of quantifying the value of water used by mines. A semi-distributed model developed within the Water Evaluation and Planning System (WEAP), was calibrated to reproduce water supply, and this was complemented with an analysis of the value of water for mining based on two methods; water markets and an analysis of its production processes. Agriculture and other users were included through methods commonly used in similar models. The outputs help understanding the value of water in the catchment, and its sensitivity to changes in climate variables, market prices, environmental regulations and changes in the production of minerals, crops and energy. The results of the project highlight the importance of merging hydrology and socio-economic calculations in mining regions, in order to better understand trade-offs and cost of opportunity of using

Magneto-hydrodynamical model for plasma

Science.gov (United States)

Liu, Ruikuan; Yang, Jiayan

2017-10-01

Based on the Newton's second law and the Maxwell equations for the electromagnetic field, we establish a new 3-D incompressible magneto-hydrodynamics model for the motion of plasma under the standard Coulomb gauge. By using the Galerkin method, we prove the existence of a global weak solution for this new 3-D model.

Ontario Hydro decontamination experience

Energy Technology Data Exchange (ETDEWEB)

Lacy, C S; Patterson, R W; Upton, M S [Chemistry and Metallurgy Department, Central Production Services, Ontario Hydro, ON (Canada)

1991-04-01

Ontario Hydro currently operates 18 nuclear electric generating units of the CANDU design with a net capacity of 12,402 MW(e). An additional 1,762 MW(e) is under construction. The operation of these facilities has underlined the need to have decontamination capability both to reduce radiation fields, as well as to control and reduce contamination during component maintenance. This paper presents Ontario Hydro decontamination experience in two key areas - full heat transport decontamination to reduce system radiation fields, and component decontamination to reduce loose contamination particularly as practised in maintenance and decontamination centres. (author)

Ontario Hydro decontamination experience

International Nuclear Information System (INIS)

Lacy, C.S.; Patterson, R.W.; Upton, M.S.

1991-01-01

Ontario Hydro currently operates 18 nuclear electric generating units of the CANDU design with a net capacity of 12,402 MW(e). An additional 1,762 MW(e) is under construction. The operation of these facilities has underlined the need to have decontamination capability both to reduce radiation fields, as well as to control and reduce contamination during component maintenance. This paper presents Ontario Hydro decontamination experience in two key areas - full heat transport decontamination to reduce system radiation fields, and component decontamination to reduce loose contamination particularly as practised in maintenance and decontamination centres. (author)

The little hydro-electricity: the boosting?

International Nuclear Information System (INIS)

Brunier, S.; Najac, C.; Roussel, A.M.; Claustre, R; Baril, D.; Marty, D.; Lefevre, P.; Arnould, M.

2007-01-01

The hydraulic energy could be easily developed in France to reach the objectives of the european directive on the renewable energies. This development can be assured by the construction of power plants perfectly integrated in their environment and respecting the rivers and assured also by the increase of the capacities of existing power plants as it is allowing by the new regulations. This document presents the place and the capacity of the hydro-electricity in France, the implementing of a green electricity, the existing regulation, the river biological continuation, the ecosystems and the little hydro-electricity and the example of the hydro-electric power plant of Scey-sur-Saone. (A.L.B.)

Collision data involving hydro-carbon molecules

International Nuclear Information System (INIS)

Tawara, H.; Itikawa, Y.; Nishimura, H.; Tanaka, H.; Nakamura, Y.

1990-07-01

Hydro-carbon molecules are abundantly produced when graphites are used as internal wall materials of hydrogen plasmas and strongly influence properties of low temperature plasmas near the edges as well as those of high temperature plasmas at the center. In this report, following simple description of the production mechanisms of hydro-carbon molecules under the interactions between graphite and hydrogen plasma, the present status of collision data for hydro-carbon molecules by electron impact is discussed and the relevant data are summarized in a series of figures and tables. It should also be noted that, in addition to fusion plasmas, these hydrocarbon data compiled here are quite useful in other applications such as plasma chemistry and material processing. (author)

Enhanced pulsed magneto-motive ultrasound imaging using superparamagnetic nanoclusters

International Nuclear Information System (INIS)

Mehrmohammadi, M; Qu, M; Emelianov, S Y; Yoon, K Y; Johnston, K P

2011-01-01

Recently, pulsed magneto-motive ultrasound (pMMUS) imaging augmented with ultra-small magnetic nanoparticles has been introduced as a tool capable of imaging events at molecular and cellular levels. The sensitivity of a pMMUS system depends on several parameters, including the size, geometry and magnetic properties of the nanoparticles. Under the same magnetic field, larger magnetic nanostructures experience a stronger magnetic force and produce larger displacement, thus improving the sensitivity and signal-to-noise ratio (SNR) of pMMUS imaging. Unfortunately, large magnetic iron-oxide nanoparticles are typically ferromagnetic and thus are very difficult to stabilize against colloidal aggregation. In the current study we demonstrate improvement of pMMUS image quality by using large size superparamagnetic nanoclusters characterized by strong magnetization per particle. Water-soluble magnetic nanoclusters of two sizes (15 and 55 nm average size) were synthesized from 3 nm iron precursors in the presence of citrate capping ligand. The size distribution of synthesized nanoclusters and individual nanoparticles was characterized using dynamic light scattering (DLS) analysis and transmission electron microscopy (TEM). Tissue mimicking phantoms containing single nanoparticles and two sizes of nanoclusters were imaged using a custom-built pMMUS imaging system. While the magnetic properties of citrate-coated nanoclusters are identical to those of superparamagnetic nanoparticles, the magneto-motive signal detected from nanoclusters is larger, i.e. the same magnetic field produced larger magnetically induced displacement. Therefore, our study demonstrates that clusters of superparamagnetic nanoparticles result in pMMUS images with higher contrast and SNR.

The Manitoba Hydro-Electric Board 50. annual report

International Nuclear Information System (INIS)

2001-01-01

This document presents the financial statements for The Manitoba Hydro-Electric Board (Manitoba Hydro) for the fiscal year ended March 31, 2001. Manitoba Hydro was proud to report no electricity rate increase for the period 2000-2001, a feat realized for the fifth consecutive year for most customer groups. Financial and production highlights were first presented, followed by the vision mission and goals of Manitoba Hydro. Manitoba Hydro serves 403 000 customers in the province with electric energy, and 248 000 customers with natural gas service mainly in the south of the province. Electricity export sale agreements are in place with more than 35 utilities and marketers in the United States, Ontario and Saskatchewan. Self-renewing waterpower is used to generate the bulk of the electricity. The transmission and distribution lines stretch over 100 000 kilometres. Manitoba Hydro is the fourth largest energy utility in Canada based on capital assets. A review of the year was presented, as well as a brief historical overview of Manitoba Hydro. The financial review section discussed the management report, the Auditor's report. Included in this section were various statement sheets, namely the consolidated statement of income and retained earnings, consolidated balance sheet, consolidated statement of cash flows, followed by some notes to the consolidated financial statements. Consolidated financial statistics and operating statistics - 10-year overview were presented. A brief presentation of the Board members and senior officers ended this report. tabs. figs

The Manitoba Hydro-Electric Board 50. annual report

Energy Technology Data Exchange (ETDEWEB)

NONE

2001-07-01

This document presents the financial statements for The Manitoba Hydro-Electric Board (Manitoba Hydro) for the fiscal year ended March 31, 2001. Manitoba Hydro was proud to report no electricity rate increase for the period 2000-2001, a feat realized for the fifth consecutive year for most customer groups. Financial and production highlights were first presented, followed by the vision mission and goals of Manitoba Hydro. Manitoba Hydro serves 403 000 customers in the province with electric energy, and 248 000 customers with natural gas service mainly in the south of the province. Electricity export sale agreements are in place with more than 35 utilities and marketers in the United States, Ontario and Saskatchewan. Self-renewing waterpower is used to generate the bulk of the electricity. The transmission and distribution lines stretch over 100 000 kilometres. Manitoba Hydro is the fourth largest energy utility in Canada based on capital assets. A review of the year was presented, as well as a brief historical overview of Manitoba Hydro. The financial review section discussed the management report, the Auditor's report. Included in this section were various statement sheets, namely the consolidated statement of income and retained earnings, consolidated balance sheet, consolidated statement of cash flows, followed by some notes to the consolidated financial statements. Consolidated financial statistics and operating statistics - 10-year overview were presented. A brief presentation of the Board members and senior officers ended this report. tabs. figs.

Magneto-optical system for high speed real time imaging

Science.gov (United States)

Baziljevich, M.; Barness, D.; Sinvani, M.; Perel, E.; Shaulov, A.; Yeshurun, Y.

2012-08-01

A new magneto-optical system has been developed to expand the range of high speed real time magneto-optical imaging. A special source for the external magnetic field has also been designed, using a pump solenoid to rapidly excite the field coil. Together with careful modifications of the cryostat, to reduce eddy currents, ramping rates reaching 3000 T/s have been achieved. Using a powerful laser as the light source, a custom designed optical assembly, and a high speed digital camera, real time imaging rates up to 30 000 frames per seconds have been demonstrated.

Development of Hydro-Mechanical Deep Drawing

DEFF Research Database (Denmark)

Zhang, Shi-Hong; Danckert, Joachim

1998-01-01

The hydro-mechanical deep-drawing process is reviewed in this article. The process principles and features are introduced and the developments of the hydro-mechanical deep-drawing process in process performances, in theory and in numerical simulation are described. The applications are summarized....... Some other related hydraulic forming processes are also dealt with as a comparison....

Magneto-Optic Fiber Gratings Useful for Dynamic Dispersion Management and Tunable Comb Filtering

International Nuclear Information System (INIS)

Bao-Jian, Wu; Xin, Lu; Kun, Qiu

2010-01-01

Intelligent control of dispersion management and tunable comb filtering in optical network applications can be performed by using magneto-optic fiber Bragg gratings (MFBGs). When a nonuniform magnetic field is applied to the MFBG with a constant grating period, the resulting grating response is equivalent to that of a conventional chirped grating. Under a linearly nonuniform magnetic field along the grating, a linear dispersion is achieved in the grating bandgap and the maximal dispersion slope can come to 1260 ps/nm 2 for a 10-mm-long fiber grating at 1550 nm window. Similarly, a Gaussian-apodizing sampled MFBG is also useful for magnetically tunable comb filtering, with potential application to clock recovery from return-to-zero optical signals and optical carrier tracking. (condensed matter: electronic structure, electrical, magnetic, and optical properties)

BC Hydro shops for GHG offsets

International Nuclear Information System (INIS)

Anon.

2000-01-01

BC Hydro is reported to have offered to purchase one million tonnes of carbon dioxide reductions in Canada's Greenhouse Gas Emissions Reduction Trading program (GERT). The program uses a baseline and credit system, where emitters purchase measurable quantities of site-specific GHG reductions. Since mid-1998, the program registered five bilateral trades and seven offers to sell. BC Hydro's recent offer is the first offer to buy. BC Hydro has made the offer to buy in expectation of the introduction of the start of the Kyoto Protocol reductions, and expects to be in the game for some time to come if it is to meet its obligations under the Kyoto Protocol. Preference will be given to projects located in Canada, but BC Hydro will consider reductions created anywhere in the world. The financial range of a single trade is between $50,000 and $1 million. (GHG offsets are currently trading in North America for between $.50 and $3.00 Cdn per metric tonne of carbon dioxide equivalent.) At present, offsets are selling at a heavily discounted price because of the uncertainty that investments made now will be credited against future regulations curbing emitters. Consequently, buying now while prices are low, may lead to sizable benefits later, depending on the actual regulations when they are promulgated. Trading now will also give BC Hydro greater credibility and assurance to have its voice heard when discussions about emissions trading and the implementation of emission trading rules reaches the serious stage

Enhanced magneto-plasmonic effect in Au/Co/Au multilayers caused by exciton–plasmon strong coupling

Energy Technology Data Exchange (ETDEWEB)

Hamidi, S.M., E-mail: m_hamidi@sbu.ac.ir; Ghaebi, O.

2016-09-15

In this paper, we have investigated magneto optical Kerr rotation using the strong coupling of exciton–plasmon. For this purpose, we have demonstrated strong coupling phenomenon using reflectometry measurements. These measurements revealed the formation of two split polaritonic extrema in reflectometry as a function of wavelength. Then we have shown exciton–plasmon coupling in dispersion diagram which presented an anti-crossing between the polaritonic branches. To assure the readers of strong coupling, we have shown an enhanced magneto-optical Kerr rotation by comparing the reflectometry results of strong coupling of surface Plasmon polariton of Au/Co/Au multilayer and R6G excitons with surface Plasmon polariton magneto-optical kerr effect experimental setup. - Highlights: • The magneto optical Kerr rotation has been investigated by using the strong coupling of exciton–plasmon. • We have shown exciton–plasmon coupling in dispersion diagram which presented an anti-crossing between the polaritonic branches. • Strong coupling of surface plasmon polariton and exciton have been yielded to the enhanced magneto-optical Kerr effect. • Plasmons in Au/Co/Au multilayer and exciton in R6G have been coupled to enhance magneto-optical activity.

Times are changing, Hydro-Quebec multiplies its assets

International Nuclear Information System (INIS)

Lefevre, M.

1997-01-01

Hydro-Quebec''s advance into the North American and world multi-energy market began with the purchase of an interest in the natural gas holding company Noverco, a commercial partnership with Gaz de France, and marketing agreements with Enron and Trigen in the United States. Hydro-Quebec, the world''s sixth largest electric utility, aims to become a multi-energy enterprise selling not only electricity, but also natural gas, oil and certain renewable forms of energy. Currently, Hydro-Quebec is licensed to make border sales of electricity at regulated prices. Through the US Federal Energy Regulatory Commission (FERC), Hydro-Quebec will be able also to sell electricity through wholesale spot contracts with electricity marketers such as Trigen and Enron

Hydro and After: The Canadian Experience with the Organization, Nationalization and Deregulation of Electrical Utilities

International Nuclear Information System (INIS)

Nelles, Henry Vivian

2003-01-01

This paper surveys the process of nationalization and some recent steps towards denationalization in a distinctive Canadian institutional setting, the provincial hydro-electric power utilities. The richest, most industrialized central province, Ontario, established a dynamic publicly owned electric generation and distribution system before World War I. Most other provinces developed variations of the regulatory model to govern private monopolies until the post World War II period when widespread nationalization at the provincial level created a near universal pattern of state owned electric companies. Recently, the process of dismantling state monopolies in this sector has begun in two provinces, one where public ownership was weakest, and the other where the concept of 'provincial hydro' was born

A hydro-optical model for deriving water quality variables from satellite images (HydroSat): A case study of the Nile River demonstrating the future Sentinel-2 capabilities

NARCIS (Netherlands)

Salama, M.; Radwan, M.; van der Velde, R.

2012-01-01

This paper describes a hydro-optical model for deriving water quality variables from satellite images, hereafter HydroSat. HydroSat corrects images for atmospheric interferences and simultaneously retrieves water quality variables. An application of HydroSat to Landsat Enhanced Thematic Mapper (ETM)

Ontario hydro radioactive material transportation field guide

International Nuclear Information System (INIS)

Howe, W.

1987-01-01

The recent introduction of both the AECB Transport Packaging of Radioactive Material Regulations and Transport Canada's Transportation of Dangerous Goods Regulations have significantly altered the requirements for transporting radioactive material in Canada. Extensive additional training as well as certification of several hundred Ontario Hydro employees has been necessary to ensure compliance with the additional and revised regulatory requirements. To assist in the training of personnel, an 'active' corporate Ontario Hydro Field Guide for Radioactive Material Transport document has been developed and published. The contents of this Field Guide identify current Ontario Hydro equipment and procedures as well as the updated relevant regulatory requirements within Canada. In addition, to satisfying Ontario Hydro requirements for this type of information over two thousand of these Field Guides have been provided to key emergency response personnel throughout the province of Ontario to assist in their transportation accident response training

Mechatronics in compressor valves - experience with HydroCOM; Mechatronik in Kompressorventilen - Betriebserfahrungen mit HydroCOM

Energy Technology Data Exchange (ETDEWEB)

Rumpold, A. [Hoerbiger Ventilwerke GmbH, Wien (Austria)

2000-03-01

Optimisation of fluid flow rates is indispensable in piston compressor operation. Messrs. Hoerbiger are producers of continuous control elements which combine mechanical and electronic components. Applications and examples of the HydroCOM control system are presented. High availability permits servicing intervals around 160,000 hours of operation. The longer operating time will improve the competitive standing of piston compressors as compared to turbocompressors and screw compressors. [German] Fuer den Betrieb von Kolbenkompressoren ist eine optimale Liefermengenregelung unverzichtbarer Bestandteil. Im Gegensatz zu herkoemmlichen Verfahren hat Hoerbiger vor zwei Jahren durch die Kombination von Mechanik und Elektronik eine neue Generation von stufenlosen Mengenregelungen auf den Markt gebracht. Anwendungsbeispiele und Betriebserfahrungen mit der HydroCOM Regelung werden vorgestellt. Hohe Verfuegbarkeit erlaubt Wartungsintervalle fuer HydroCOM Aktuatoren von ca. 16000 Betriebsstunden. Und aufgrund der generell verbesserten Standzeiten von Packungen, Kolbenringen und Ventilen erzielt der so geregelte Kolbenkompressor hohe Attraktivitaet gegenueber Turbo- und Schraubenverdichtern. (orig./AKF)

A complex-polarization-propagator protocol for magneto-chiral axial dichroism and birefringence dispersion

DEFF Research Database (Denmark)

Cukras, Janusz; Kauczor, Joanna; Norman, Patrick

2016-01-01

A computational protocol for magneto-chiral dichroism and magneto-chiral birefringence dispersion is presented within the framework of damped response theory, also known as complex polarization propagator theory, at the level of time-dependent Hartree–Fock and time-dependent density functional th...

Sample-size resonance, ferromagnetic resonance and magneto-permittivity resonance in multiferroic nano-BiFeO3/paraffin composites at room temperature

International Nuclear Information System (INIS)

Wang, Lei; Li, Zhenyu; Jiang, Jia; An, Taiyu; Qin, Hongwei; Hu, Jifan

2017-01-01

In the present work, we demonstrate that ferromagnetic resonance and magneto-permittivity resonance can be observed in appropriate microwave frequencies at room temperature for multiferroic nano-BiFeO 3 /paraffin composite sample with an appropriate sample-thickness (such as 2 mm). Ferromagnetic resonance originates from the room-temperature weak ferromagnetism of nano-BiFeO 3 . The observed magneto-permittivity resonance in multiferroic nano-BiFeO 3 is connected with the dynamic magnetoelectric coupling through Dzyaloshinskii–Moriya (DM) magnetoelectric interaction or the combination of magnetostriction and piezoelectric effects. In addition, we experimentally observed the resonance of negative imaginary permeability for nano BiFeO 3 /paraffin toroidal samples with longer sample thicknesses D=3.7 and 4.9 mm. Such resonance of negative imaginary permeability belongs to sample-size resonance. - Highlights: • Nano-BiFeO 3 /paraffin composite shows a ferromagnetic resonance. • Nano-BiFeO 3 /paraffin composite shows a magneto-permittivity resonance. • Resonance of negative imaginary permeability in BiFeO 3 is a sample-size resonance. • Nano-BiFeO 3 /paraffin composite with large thickness shows a sample-size resonance.

HydroSHEDS: A global comprehensive hydrographic dataset

Science.gov (United States)

Wickel, B. A.; Lehner, B.; Sindorf, N.

2007-12-01

The Hydrological data and maps based on SHuttle Elevation Derivatives at multiple Scales (HydroSHEDS) is an innovative product that, for the first time, provides hydrographic information in a consistent and comprehensive format for regional and global-scale applications. HydroSHEDS offers a suite of geo-referenced data sets, including stream networks, watershed boundaries, drainage directions, and ancillary data layers such as flow accumulations, distances, and river topology information. The goal of developing HydroSHEDS was to generate key data layers to support regional and global watershed analyses, hydrological modeling, and freshwater conservation planning at a quality, resolution and extent that had previously been unachievable. Available resolutions range from 3 arc-second (approx. 90 meters at the equator) to 5 minute (approx. 10 km at the equator) with seamless near-global extent. HydroSHEDS is derived from elevation data of the Shuttle Radar Topography Mission (SRTM) at 3 arc-second resolution. The original SRTM data have been hydrologically conditioned using a sequence of automated procedures. Existing methods of data improvement and newly developed algorithms have been applied, including void filling, filtering, stream burning, and upscaling techniques. Manual corrections were made where necessary. Preliminary quality assessments indicate that the accuracy of HydroSHEDS significantly exceeds that of existing global watershed and river maps. HydroSHEDS was developed by the Conservation Science Program of the World Wildlife Fund (WWF) in partnership with the U.S. Geological Survey (USGS), the International Centre for Tropical Agriculture (CIAT), The Nature Conservancy (TNC), and the Center for Environmental Systems Research (CESR) of the University of Kassel, Germany.

Experience of pico/micro hydro based power generation

Energy Technology Data Exchange (ETDEWEB)

Murthy, S.S. [Indian Inst. of Technology, Delhi, New Delhi (India). Dept. of Electrical Engineering

2010-07-01

Although India has approximately 150,000 megawatts of hydro potential, only a small portion is tapped. There is also significant untapped hydro potential in many developing countries such as Nepal, Bhutan, Vietnam, Indonesia and regions in South America and Africa. Small-scale hydroelectric power systems with capacities of up to a few megawatts are eco-friendly and sustainable. They can be classified based on unit sizes as pico (u pto 10 kilowatts), micro (10-100 kilowatts) and mini (100 kilowatts to a few megawatts) hydro systems. Mini hydro systems are always grid connected while micro can be either grid connected or off grid. Pico is always off grid. In India, there are thousands of favorable sites in this range that should be tapped for distributed power generation to electrify local communities. This need is reflected by the global emphasis on distributed power generation as well as the Government of India's policy to promote this type of power generation. A working stand alone pico-hydro power generating system has been successfully installed in 5 sites in Karnataka. The purpose of the project was to demonstrate the technical, managerial and economic feasibility of setting up small hydro projects in remote hilly areas of Karnataka, India and its positive environmental impact. The presentation discussed the site selection criteria; installed sites of pico hydro; system description; parts of the system; the electric load controller; types of electronic load controllers; and a description of the unit and control scheme. tabs., figs.

Brigham City Hydro Generation Project

Energy Technology Data Exchange (ETDEWEB)

Ammons, Tom B. [Energy Conservation Specialist, Port Ewen, NY (United States)

2015-10-31

Brigham City owns and operates its own municipal power system which currently includes several hydroelectric facilities. This project was to update the efficiency and capacity of current hydro production due to increased water flow demands that could pass through existing generation facilities. During 2006-2012, this project completed efficiency evaluation as it related to its main objective by completing a feasibility study, undergoing necessary City Council approvals and required federal environmental reviews. As a result of Phase 1 of the project, a feasibility study was conducted to determine feasibility of hydro and solar portions of the original proposal. The results indicated that the existing Hydro plant which was constructed in the 1960’s was running at approximately 77% efficiency or less. Brigham City proposes that the efficiency calculations be refined to determine the economic feasibility of improving or replacing the existing equipment with new high efficiency equipment design specifically for the site. Brigham City completed the Feasibility Assessment of this project, and determined that the Upper Hydro that supplies the main culinary water to the city was feasible to continue with. Brigham City Council provided their approval of feasibility assessment’s results. The Upper Hydro Project include removal of the existing powerhouse equipment and controls and demolition of a section of concrete encased penstock, replacement of penstock just upstream of the turbine inlet, turbine bypass, turbine shut-off and bypass valves, turbine and generator package, control equipment, assembly, start-up, commissioning, Supervisory Control And Data Acquisition (SCADA), and the replacement of a section of conductors to the step-up transformer. Brigham City increased the existing 575 KW turbine and generator with an 825 KW turbine and generator. Following the results of the feasibility assessment Brigham City pursued required environmental reviews with the DOE and

MAGNETO-FRICTIONAL MODELING OF CORONAL NONLINEAR FORCE-FREE FIELDS. I. TESTING WITH ANALYTIC SOLUTIONS

Energy Technology Data Exchange (ETDEWEB)

Guo, Y.; Keppens, R. [School of Astronomy and Space Science, Nanjing University, Nanjing 210023 (China); Xia, C. [Centre for mathematical Plasma-Astrophysics, Department of Mathematics, KU Leuven, B-3001 Leuven (Belgium); Valori, G., E-mail: guoyang@nju.edu.cn [University College London, Mullard Space Science Laboratory, Holmbury St. Mary, Dorking, Surrey RH5 6NT (United Kingdom)

2016-09-10

We report our implementation of the magneto-frictional method in the Message Passing Interface Adaptive Mesh Refinement Versatile Advection Code (MPI-AMRVAC). The method aims at applications where local adaptive mesh refinement (AMR) is essential to make follow-up dynamical modeling affordable. We quantify its performance in both domain-decomposed uniform grids and block-adaptive AMR computations, using all frequently employed force-free, divergence-free, and other vector comparison metrics. As test cases, we revisit the semi-analytic solution of Low and Lou in both Cartesian and spherical geometries, along with the topologically challenging Titov–Démoulin model. We compare different combinations of spatial and temporal discretizations, and find that the fourth-order central difference with a local Lax–Friedrichs dissipation term in a single-step marching scheme is an optimal combination. The initial condition is provided by the potential field, which is the potential field source surface model in spherical geometry. Various boundary conditions are adopted, ranging from fully prescribed cases where all boundaries are assigned with the semi-analytic models, to solar-like cases where only the magnetic field at the bottom is known. Our results demonstrate that all the metrics compare favorably to previous works in both Cartesian and spherical coordinates. Cases with several AMR levels perform in accordance with their effective resolutions. The magneto-frictional method in MPI-AMRVAC allows us to model a region of interest with high spatial resolution and large field of view simultaneously, as required by observation-constrained extrapolations using vector data provided with modern instruments. The applications of the magneto-frictional method to observations are shown in an accompanying paper.

Magneto-optic gradient effect in domain-wall images: at the crossroads of magneto-optics and micromagnetics

Czech Academy of Sciences Publication Activity Database

Kamberský, Vladimír; Schäfer, R.

2011-01-01

Roč. 84, č. 1 (2011), 013815/1-013815/6 ISSN 1050-2947 Institutional research plan: CEZ:AV0Z10100521 Keywords : edge and boundary effects * reflection and refraction * diffraction and scattering * magneto-optical effects * theory * models * numerical simulation Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 2.878, year: 2011

IPPSO raises Hydro exports in smog negotiations

International Nuclear Information System (INIS)

Anon.

1997-01-01

The Independent Power Producers of Ontario (IPPSO) requested federal and provincial committees negotiating atmospheric emission standards to review Ontario Hydro's export wheeling plans. IPPSO alleges that Ontario Hydro is preparing to apply pressure on the Canadian export approval process, and is building up a major effort that will increase emissions, contrary to the objectives embodied in a number of environment protection projects such as the Ontario Smog Plan, The Federal-Provincial NOx Management Plan, the Strategic Options Plan, or the Convention on Long-Range Transboundary Air Pollution Draft NOx Protocol Negotiations. IPPSO alleges further that while Ontario Hydro is one of Canada's largest single emitter of greenhouse gases NOx, and SO 2 , and as a public sector corporation it should be the most amenable to serving the public good, the Corporation is doing exactly the opposite: it actively prevents production of electricity from less polluting sources. It is IPPSO's contention that Ontario Hydro's desire to control the Ontario market could come at significant cost to the environment

Hydrological Modeling in Alaska with WRF-Hydro

Science.gov (United States)

Elmer, N. J.; Zavodsky, B.; Molthan, A.

2017-12-01

The operational National Water Model (NWM), implemented in August 2016, is an instantiation of the Weather Research and Forecasting hydrological extension package (WRF-Hydro). Currently, the NWM only covers the contiguous United States, but will be expanded to include an Alaska domain in the future. It is well known that Alaska presents several hydrological modeling challenges, including unique arctic/sub-arctic hydrological processes not observed elsewhere in the United States and a severe lack of in-situ observations for model initialization. This project sets up an experimental version of WRF-Hydro in Alaska mimicking the NWM to gauge the ability of WRF-Hydro to represent hydrological processes in Alaska and identify model calibration challenges. Recent and upcoming launches of hydrology-focused NASA satellite missions such as the Soil Moisture Active Passive (SMAP) and Surface Water Ocean Topography (SWOT) expand the spatial and temporal coverage of observations in Alaska, so this study also lays the groundwork for assimilating these NASA datasets into WRF-Hydro in the future.

Quantitative magneto-optical investigation of superconductor/ferromagnet hybrid structures.

Science.gov (United States)

Shaw, G; Brisbois, J; Pinheiro, L B G L; Müller, J; Blanco Alvarez, S; Devillers, T; Dempsey, N M; Scheerder, J E; Van de Vondel, J; Melinte, S; Vanderbemden, P; Motta, M; Ortiz, W A; Hasselbach, K; Kramer, R B G; Silhanek, A V

2018-02-01

We present a detailed quantitative magneto-optical imaging study of several superconductor/ferromagnet hybrid structures, including Nb deposited on top of thermomagnetically patterned NdFeB and permalloy/niobium with erasable and tailored magnetic landscapes imprinted in the permalloy layer. The magneto-optical imaging data are complemented with and compared to scanning Hall probe microscopy measurements. Comprehensive protocols have been developed for calibrating, testing, and converting Faraday rotation data to magnetic field maps. Applied to the acquired data, they reveal the comparatively weaker magnetic response of the superconductor from the background of larger fields and field gradients generated by the magnetic layer.

Quantitative magneto-optical investigation of superconductor/ferromagnet hybrid structures

Science.gov (United States)

Shaw, G.; Brisbois, J.; Pinheiro, L. B. G. L.; Müller, J.; Blanco Alvarez, S.; Devillers, T.; Dempsey, N. M.; Scheerder, J. E.; Van de Vondel, J.; Melinte, S.; Vanderbemden, P.; Motta, M.; Ortiz, W. A.; Hasselbach, K.; Kramer, R. B. G.; Silhanek, A. V.

2018-02-01

We present a detailed quantitative magneto-optical imaging study of several superconductor/ferromagnet hybrid structures, including Nb deposited on top of thermomagnetically patterned NdFeB and permalloy/niobium with erasable and tailored magnetic landscapes imprinted in the permalloy layer. The magneto-optical imaging data are complemented with and compared to scanning Hall probe microscopy measurements. Comprehensive protocols have been developed for calibrating, testing, and converting Faraday rotation data to magnetic field maps. Applied to the acquired data, they reveal the comparatively weaker magnetic response of the superconductor from the background of larger fields and field gradients generated by the magnetic layer.

Canadian hydro potential in the North American market

International Nuclear Information System (INIS)

Adams, K.

2002-01-01

Canada's hydro potential in the North American energy market was discussed. Canada is a net exporter of electricity in North America, and since 1990, has exported an average of 28 Terawatt hours/year to the United States. More than 65 per cent of these exports were generated from hydro power plants. It was emphasized that significant reductions in greenhouse gases can be achieved if Canadian hydroelectricity is substituted for coal power generation. It was also noted that although there may not be enough hydro capacity to meet all of North America's energy requirements, development of new large hydro resources in Canada could help meet the growing demand for electricity in the United States. Hydro can also complement other renewable energy sources such as wind and solar. The factors that will determine if Canadian hydropower will contribute to the energy demand are market mechanisms such as greenhouse gas credit trading systems which provide incentive for renewable energy projects. In addition, the existing infrastructure must be expanded both east and west within Canada and north and south between Canada and the United States. 5 figs

Annual report 1993 (Ontario Hydro, Toronto)

Energy Technology Data Exchange (ETDEWEB)

NONE

1994-12-31

Ontario Hydro`s prime objective is to supply the people of Ontario with electricity at cost while maintaining high standards of safety and service. The annual report presents energy efficiency and competitiveness, operations in review, the environmental performance of the Corporation, the future, and choices for a sustainable future. A financial review and analysis is also provided, along with an auditor`s report and financial statements.

Electrical and magneto transport properties of

Indian Academy of Sciences (India)

samples. The morphology of crystal grains shows that the grains are nearly uniform in size and spherical. Electrical .... 1.5406 Å) in angular steps of 0.02 .... table to scattering by impurities, defects, grain boundaries .... because of different orientations of opposite spins, an energy ... 2000 Colossal magneto resistance oxides.

Dynamic modeling, simulation and control design of an advanced micro-hydro power plant for distributed generation applications

Energy Technology Data Exchange (ETDEWEB)

Marquez, J.L. [Instituto de Energia Electrica, Universidad Nacional de San Juan, Av. Libertador San Martin Oeste 1109, J5400ARL San Juan (Argentina); Molina, M.G. [CONICET, Instituto de Energia Electrica, Universidad Nacional de San Juan, Av. Libertador San Martin Oeste 1109, J5400ARL San Juan (Argentina); Pacas, J.M. [Institut fuer Leistungselektronik und Elektrische Antriebe, Universitaet Siegen, Fachbereich 12 Hoelderlinstr 3, D 57068 Siegen (Germany)

2010-06-15

A small-scale hydropower station is usually a run-of-river plant that uses a fixed speed drive with mechanical regulation of the turbine water flow rate for controlling the active power generation. This design enables to reach high efficiency over a wide range of water flows but using a complex operating mechanism, which is in consequence expensive and tend to be more affordable for large systems. This paper proposes an advanced structure of a micro-hydro power plant (MHPP) based on a smaller, lighter, more robust and more efficient higher-speed turbine. The suggested design is much simpler and eliminates all mechanical adjustments through a novel electronic power conditioning system for connection to the electric grid. In this way, it allows obtaining higher reliability and lower cost of the power plant. A full detailed model of the MHPP is derived and a new three-level control scheme is designed. The dynamic performance of the proposed MHPP is validated through digital simulations and employing a small-scale experimental set-up. (author)

Alexela ostab Hydro Texaco tanklaketi / Gert D. Hankewitz

Index Scriptorium Estoniae

Hankewitz, Gert D.

2006-01-01

Kütusefirma Alexela Oil teatas, et ostab tanklaketi Hydro Texaco kõik Balti riikide tanklad. Diagramm: Alexela ja Hydro Texaco majandusnäitajad. Vt. samas: Statoili juht: ühinemine turul muutusi ei too

Spatial heterogeneities and variability of karst hydro-system : insights from geophysics

Science.gov (United States)

Champollion, C.; Fores, B.; Lesparre, N.; Frederic, N.

2017-12-01

Heterogeneous systems such as karsts or fractured hydro-systems are challenging for both scientist and groundwater resources management. Karsts heterogeneities prevent the comparison and moreover the combination of data representative of different scales: borehole water level can generally not be used directly to interpret spring flow dynamic for example. The spatial heterogeneity has also an impact on the temporal variability of groundwater transfer and storage. Karst hydro-systems have characteristic non linear relation between precipitation amount and discharge at the outlets with threshold effects and a large variability of groundwater transit times In the presentation, geophysical field experiments conducted in karst hydro-system in the south of France are used to investigate groundwater transfer and storage variability at a scale of a few hundred meters. We focus on the added value of both geophysical time-lapse gravity experiments and 2D ERT imaging of the subsurface heterogeneities. Both gravity and ERT results can only be interpreted with large ambiguity or some strong a priori: the relation between resistivity and water content is not unique; almost no information about the processes can be inferred from the groundwater stock variations. The present study demonstrate how the ERT and gravity field experiments can be interpreted together in a coherent scheme with less ambiguity. First the geological and hydro-meteorological context is presented. Then the ERT field experiment including the processing and the results are detailed in the section about geophysical imaging of the heterogeneities. The gravity double difference (S2D) time-lapse experiment is described in the section about geophysical monitoring of the temporal variability. The following discussion demonstrate the impact of both experiments on the interpretation in terms of processes and heterogeneities.

The HydroServer Platform for Sharing Hydrologic Data

Science.gov (United States)

Tarboton, D. G.; Horsburgh, J. S.; Schreuders, K.; Maidment, D. R.; Zaslavsky, I.; Valentine, D. W.

2010-12-01

The CUAHSI Hydrologic Information System (HIS) is an internet based system that supports sharing of hydrologic data. HIS consists of databases connected using the Internet through Web services, as well as software for data discovery, access, and publication. The HIS system architecture is comprised of servers for publishing and sharing data, a centralized catalog to support cross server data discovery and a desktop client to access and analyze data. This paper focuses on HydroServer, the component developed for sharing and publishing space-time hydrologic datasets. A HydroServer is a computer server that contains a collection of databases, web services, tools, and software applications that allow data producers to store, publish, and manage the data from an experimental watershed or project site. HydroServer is designed to permit publication of data as part of a distributed national/international system, while still locally managing access to the data. We describe the HydroServer architecture and software stack, including tools for managing and publishing time series data for fixed point monitoring sites as well as spatially distributed, GIS datasets that describe a particular study area, watershed, or region. HydroServer adopts a standards based approach to data publication, relying on accepted and emerging standards for data storage and transfer. CUAHSI developed HydroServer code is free with community code development managed through the codeplex open source code repository and development system. There is some reliance on widely used commercial software for general purpose and standard data publication capability. The sharing of data in a common format is one way to stimulate interdisciplinary research and collaboration. It is anticipated that the growing, distributed network of HydroServers will facilitate cross-site comparisons and large scale studies that synthesize information from diverse settings, making the network as a whole greater than the sum of its

Sample-size resonance, ferromagnetic resonance and magneto-permittivity resonance in multiferroic nano-BiFeO{sub 3}/paraffin composites at room temperature

Energy Technology Data Exchange (ETDEWEB)

Wang, Lei; Li, Zhenyu; Jiang, Jia; An, Taiyu; Qin, Hongwei; Hu, Jifan, E-mail: hujf@sdu.edu.cn

2017-01-01

In the present work, we demonstrate that ferromagnetic resonance and magneto-permittivity resonance can be observed in appropriate microwave frequencies at room temperature for multiferroic nano-BiFeO{sub 3}/paraffin composite sample with an appropriate sample-thickness (such as 2 mm). Ferromagnetic resonance originates from the room-temperature weak ferromagnetism of nano-BiFeO{sub 3}. The observed magneto-permittivity resonance in multiferroic nano-BiFeO{sub 3} is connected with the dynamic magnetoelectric coupling through Dzyaloshinskii–Moriya (DM) magnetoelectric interaction or the combination of magnetostriction and piezoelectric effects. In addition, we experimentally observed the resonance of negative imaginary permeability for nano BiFeO{sub 3}/paraffin toroidal samples with longer sample thicknesses D=3.7 and 4.9 mm. Such resonance of negative imaginary permeability belongs to sample-size resonance. - Highlights: • Nano-BiFeO{sub 3}/paraffin composite shows a ferromagnetic resonance. • Nano-BiFeO{sub 3}/paraffin composite shows a magneto-permittivity resonance. • Resonance of negative imaginary permeability in BiFeO{sub 3} is a sample-size resonance. • Nano-BiFeO{sub 3}/paraffin composite with large thickness shows a sample-size resonance.

Viscosity and Vorticity in Reduced Magneto-Hydrodynamics

Energy Technology Data Exchange (ETDEWEB)

Joseph, Ilon [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

2015-08-12

Magneto-hydrodynamics (MHD) critically relies on viscous forces in order for an accurate determination of the electric eld. For each charged particle species, the Braginskii viscous tensor for a magnetized plasma has the decomposition into matrices with special symmetries.

Magneto-structural correlations in exchange coupled systems

International Nuclear Information System (INIS)

Willett, R.D.; Gatteschi, D.; Kahn, O.

1985-01-01

This book contains 19 chapters. Some of the chapter titles are: Optical Spectroscophy; The Basis of Spin-Hamiltonian Theory; Inelastic Neutorn Scattering From Clusters; Magneto-structural Correlations in Bioinorganic Chemistry; and Magnetic Exchange Interactions Propagated by Multi-Atom Bridges

Wound bed preparation: A novel approach using HydroTherapy.

Science.gov (United States)

Atkin, Leanne; Ousey, Karen

2016-12-01

Wounds that fail to heal quickly are often encountered by community nursing staff. An important step in assisting these chronic or stalled wounds progress through healing is debridement to remove devitalised tissue, including slough and eschar, that can prevent the wound from healing. A unique wound treatment called HydroTherapy aims to provide an optimal healing environment. The first step of HydroTherapy involves HydroClean plus™, this dressing enables removal of devitalised tissue through autolytic debridement and absorption of wound fluid. Irrigation and cleansing provided by Ringer's solution from the dressing further removes any necrotic tissue or eschar. Once effective wound bed preparation has been achieved a second dressing, HydroTac™, provides an ongoing hydrated wound environment that enables re-epithelialisation to occur in an unrestricted fashion. This paper presents 3 case studies of slow healing wounds treated with HydroClean plus™ which demonstrates effective wound debridement.

BOT schemes as financial model of hydro power projects

International Nuclear Information System (INIS)

Grausam, A.

1997-01-01

Build-operate-transfer (BOT) schemes are the latest methods adopted in the developing infrastructure projects. This paper outlines the project financing through BOT schemes and briefly focuses on the factors particularly relevant to hydro power projects. Hydro power development provides not only the best way to produce electricity, it can also solve problems in different fields, such as navigation problems in case of run-of-the river plants, ground water management systems and flood control etc. This makes HPP projects not cheaper, but hydro energy is a clean and renewable energy and the hydro potential worldwide will play a major role to meet the increased demand in future. 5 figs

An artificial intelligence (AI) NOx/heat rate optimization system for Ontario Hydro`s fossil generating stations

Energy Technology Data Exchange (ETDEWEB)

Luk, J.; Frank, A.; Bodach, P. [Ontario Hydro, Toronto, ON (Canada); Warriner, G. [Radian International, Tucker, GA (United States); Noblett, J. [Radian International, Austin, TX (United States); Slatsky, M. [Southern Company, Birmingham, AL (United States)

1999-08-01

Artificial intelligence (AI)-based software packages which can optimize power plant operations that improves heat rate and also reduces nitrogen oxide emissions are now commonly available for commercial use. This paper discusses the implementation of the AI-based NOx and Heat Rate Optimization System at Ontario Hydro`s generation stations, emphasizing the current AI Optimization Project at Units 5 and 6 of the Lakeview Generating Station. These demonstration programs are showing promising results in NOx reduction and plant performance improvement. The availability of the plant Digital Control System (DCS) in implementing AI optimization in a closed-loop system was shown to be an important criterion for success. Implementation of AI technology at other Ontario Hydro fossil generating units as part of the overall NOx emission reduction system is envisaged to coincide with the retrofit of the original plant control system with the latest DCS systems. 14 refs., 3 figs.

Fluid dynamics transactions

CERN Document Server

Fiszdon, W

1965-01-01

Fluid Dynamics Transactions, Volume 2 compiles 46 papers on fluid dynamics, a subdiscipline of fluid mechanics that deals with fluid flow. The topics discussed in this book include developments in interference theory for aeronautical applications; diffusion from sources in a turbulent boundary layer; unsteady motion of a finite wing span in a compressible medium; and wall pressure covariance and comparison with experiment. The certain classes of non-stationary axially symmetric flows in magneto-gas-dynamics; description of the phenomenon of secondary flows in curved channels by means of co

Faraday effect in hybrid magneto-plasmonic photonic crystals.

Science.gov (United States)

Caballero, B; García-Martín, A; Cuevas, J C

2015-08-24

We present a theoretical study of the Faraday effect in hybrid magneto-plasmonic crystals that consist of Au-Co-Au perforated membranes with a periodic array of sub-wavelength holes. We show that in these hybrid systems the interplay between the extraordinary optical transmission and the magneto-optical activity leads to a resonant enhancement of the Faraday rotation, as compared to purely ferromagnetic membranes. In particular, we determine the geometrical parameters for which this enhancement is optimized and show that the inclusion of a noble metal like Au dramatically increases the Faraday rotation over a broad bandwidth. Moreover, we show that the analysis of the Faraday rotation in these periodically perforated membranes provides a further insight into the origin of the extraordinary optical transmission.

?Strange Attractors (chaos) in the hydro-climatology of Colombia?

International Nuclear Information System (INIS)

Poveda Jaramillo, German

1997-01-01

Inter annual hydro-climatology of Colombia is strongly influenced by extreme phases of ENSO, a phenomenon exhibiting many features of chaotic non-linear system. The possible chaotic nature of Colombian hydrology is examined by using time series of monthly precipitation at Bogota (1866-1992) and Medellin (1908-1995), and average stream flows of the Magdalena River at Puerto Berrio. The power spectrum, the Haussdorf-Besikovich (fractal) dimension, the correlation dimension, and the largest Lyapunov exponent are estimated for the time series. Ideas of hydrologic forecasting and predictability are discussed in the context of nonlinear dynamical systems exhibit chaotic behavior

Hydrangea-like magneto-fluorescent nanoparticles through thiol-inducing assembly

Science.gov (United States)

Chen, Shun; Zhang, Junjun; Song, Shaokun; Xiong, Chuanxi; Dong, Lijie

2017-01-01

Magneto-fluorescent nanoparticles (NPs), recognized as an emerging class of materials, have drawn much attention because of their potential applications. Due to surface functionalization and thiol-metal bonds, a simple method has been put forward for fabricating hydrangea-like magneto-fluorescent Fe3O4-SH@QD NPs, through assembling thiol-modified Fe3O4 NPs with sub-size multi-layer core/shell CdSe/CdS/ZnS QDs. After a refined but controllable silane hydrolysis process, thiol-modified Fe3O4 was fabricated, resulting in Fe3O4-SH@QD NPs with QDs, while preventing the quenching of the QDs. As a result, the core Fe3O4 NPs were 18 nm in diameter, while the scattered CdSe/CdS/ZnS QDs were 7 nm in diameter. The resultant magneto-fluorescent Fe3O4-SH@QD NPs exhibit efficient fluorescence, superparamagnetism at room temperature, and rapid response to the external field, which make them ideal candidates for difunctional probes in MRI and bio-labels, targeting and photodynamic therapy, and cell tracking and separation.

Experimental investigation of torsional vibration isolation using Magneto Rheological Elastomer

Directory of Open Access Journals (Sweden)

Praveen Shenoy K

2018-01-01

Full Text Available Rotating systems suffer from lateral and torsional vibrations which have detrimental effect on the roto-dynamic performance. Many available technologies such as vibration isolators and vibration absorbers deal with the torsional vibrations to a certain extent, however passive isolators and absorbers find less application when the input conditions are dynamic. The present work discusses use of a smart material called as Magneto Rheological Elastomer (MRE, whose properties can be changed based on magnetic field input, as a potential isolator for torsional vibrations under dynamic loading conditions. Carbonyl Iron Particles (CIP of average size 5 μm were mixed with RTV Silicone rubber to form the MRE. The effect of magnetic field on the system parameters was comprehended under impulse loading conditions using a custom built in-house system. Series arrangement of accelerometers were used to differentiate between the torsional and the bending modes of vibration of the system. Impact hammer tests were carried out on the torsional system to study its response, in the presence and absence of magnetic field. The tests revealed a shift in torsional frequency in the presence of magnetic field which elucidates the ability of MRE to work as a potential vibration isolator for torsional systems.

Advanced lattice Boltzmann scheme for high-Reynolds-number magneto-hydrodynamic flows

Science.gov (United States)

De Rosis, Alessandro; Lévêque, Emmanuel; Chahine, Robert

2018-06-01

Is the lattice Boltzmann method suitable to investigate numerically high-Reynolds-number magneto-hydrodynamic (MHD) flows? It is shown that a standard approach based on the Bhatnagar-Gross-Krook (BGK) collision operator rapidly yields unstable simulations as the Reynolds number increases. In order to circumvent this limitation, it is here suggested to address the collision procedure in the space of central moments for the fluid dynamics. Therefore, an hybrid lattice Boltzmann scheme is introduced, which couples a central-moment scheme for the velocity with a BGK scheme for the space-and-time evolution of the magnetic field. This method outperforms the standard approach in terms of stability, allowing us to simulate high-Reynolds-number MHD flows with non-unitary Prandtl number while maintaining accuracy and physical consistency.

The different modes of hydro-economic analysis (Invited)

Science.gov (United States)

Harou, J. J.; Binions, O.; Erfani, T.

2013-12-01

In the face of growing water demands, climate change and spatial and temporal water access variability, accurately assessing the economic impacts of proposed water resource management changes is useful. The objective of this project funded by UK Water Industry Research was to present and demonstrate a framework for identifying and using the ';value of water' to enable water utilities and their regulators to make better decisions. A hydro-economic model can help evaluate water management options in terms of their hydrological and economic impact at different locations throughout a catchment over time. In this talk we discuss three modes in which hydro-economic models can be implemented: evaluative, behavioral and prescriptive. In evaluation mode economic water demand and benefit functions are used to post-process water resource management model results to assess the economic impacts (over space and time) of a policy under consideration. In behavioral hydro-economic models users are represented as agents and the economics is used to help predict their actions. In prescriptive mode optimization is used to find the most economically efficient management actions such as allocation patterns or source selection. These three types of hydro-economic analysis are demonstrated on a UK watershed (Great River Ouse) that includes 97 different water abstractors from amongst the public water supply, agriculture, industry and energy plant cooling sectors. The following issues under dry and normal historical conditions were investigated: Supply/demand investment planning, societal cost of environmental flows, water market prices, and scarcity-sensitive charges for water rights. The talk discusses which hydro-economic modeling mode is used to study each of these issues and why; example results are shown and discussed. The topic of how hydro-economic models can be built and deployed effectively is covered along with how existing water utility operational and planning tools can be

Overview of Hydrometeorologic Forecasting Procedures at BC Hydro

Science.gov (United States)

McCollor, D.

2004-12-01

Energy utility companies must balance production from limited sources with increasing demand from industrial, business, and residential consumers. The utility planning process requires a balanced, efficient, and effective distribution of energy from source to consumer. Therefore utility planners must consider the impact of weather on energy production and consumption. Hydro-electric companies should be particularly tuned to weather because their source of energy is water, and water supply depends on precipitation. BC Hydro operates as the largest hydro-electric company in western Canada, managing over 30 reservoirs within the province of British Columbia, and generating electricity for 1.6 million people. BC Hydro relies on weather forecasts of watershed precipitation and temperature to drive hydrologic reservoir inflow models and of urban temperatures to meet energy demand requirements. Operations and planning specialists in the company rely on current, value-added weather forecasts for extreme high-inflow events, daily reservoir operations planning, and long-term water resource management. Weather plays a dominant role for BC Hydro financial planners in terms of sensitive economic responses. For example, a two percent change in hydropower generation, due in large part to annual precipitation patterns, results in an annual net change of \\50 million in earnings. A five percent change in temperature produces a \\5 million change in yearly earnings. On a daily basis, significant precipitation events or temperature extremes involve potential profit/loss decisions in the tens of thousands of dollars worth of power generation. These factors are in addition to environmental and societal costs that must be considered equally as part of a triple bottom line reporting structure. BC Hydro water resource managers require improved meteorological information from recent advancements in numerical weather prediction. At BC Hydro, methods of providing meteorological forecast data

BC Hydro triple bottom line report 2002

International Nuclear Information System (INIS)

Anon

2002-08-01

British Columbia Hydro (BC Hydro) published this document which measures the environmental, social and economic performance of the company. It is a complement to BC Hydro's 2002 Annual Report. The report was prepared to better understand the company's business in terms of its commitment to being an environmentally, socially, and economically responsible company (the three bottom lines). BC Hydro proved its ability to integrate the three bottom lines in decision making processes by carefully examining the environmental, social and economical impacts of programs such as Power Smart, Green and Alternative Energy, and Water Use Planning. All indicators point to BC Hydro achieving its commitment of providing a minimum of 10 per cent of new demand through 2010 with new green energy sources. Water Use Plans were developed for hydroelectric generating stations, and they should all be in place by 2003. Efficiencies realised through the Power Smart program offset the increases in greenhouse gas associated with increased energy demand. Juvenile sturgeon raised in a hatchery were released into the Columbia River in May 2002. The completion of a 40-kilometre trail on the Sunshine Coast was helped by a financial contribution from BC Hydro in the amount of 23,000 dollars. Safety improvements were implemented at eight facilities, such as dam remediation, dam surveillance and instrumentation updates. Scholarships were awarded across the province, along with additional donations to non-profit organizations. Co-op positions were provided for 150 students. Internal energy efficiency programs were successful. Planning is under way for significant maintenance work and equipment replacement projects as the transmission and distribution infrastructure ages. The number of reported indicators was expanded this year. In turn, they were aligned with the revised Global Reporting Initiative (GRI) guidelines. tabs

Ontario Hydro Research Division annual report 1988

International Nuclear Information System (INIS)

1988-01-01

The Research Division of Ontario Hydro conducts research in the fields of chemistry, civil engineering, electrical engineering, mechanical engineering, metallurgy, and operations. Much of the research has a bearing on the safe, environmentally benign operation of Ontario Hydro's nuclear power plants. Particular emphasis has been placed on nuclear plant component aging and plant life assurance

Impact of flocculation on flotation tailing's hydro-cycloning properties

Directory of Open Access Journals (Sweden)

Knežević Dinko N.

2014-01-01

Full Text Available Research results of hydro-cycloning of flocculated and non-flocculated flotation tailing from the lead and zinc open pit mine 'Suplja stijena', Sula - Montenegro have been shown in this paper. Reason for this research was finding conditions in order to separate fraction that is suitable for embankment erection. Flotation tailings has been tested in the very state that it goes out from the flotation process and tailings which is flocculated by anionic flocculant. The object was to determine the impact of flocculation on properties of hydro-cycloning products and disposal process. In hydro-cycloning process greater underflow mass is being separated with non-flocculated tailing. Values of geomechanical parameters are significantly different, especially hydro-cyclone's underflow. All geomechanical parameters of hydro-cyclone's underflow are suitable for erecting embankment which shall be made from non-flocculated tailing. Underflow drainage of non-flocculated tailing is faster while overflow drainage is slower and problematic with both tailings.

Competition policy and regulation in hydro-dominated electricity markets

International Nuclear Information System (INIS)

Rangel, Luiz Fernando

2008-01-01

This paper discusses the main competition issues that arise in electricity systems dominated by hydro generation, arguing that technological differences between hydro and thermal plants may allow hydropower producers to exert market power in different and subtler ways compared to thermal generators. The key for market power in hydro-based systems is the strategic allocation of a given amount of output across periods, rather than a straightforward reduction of total output. The paper examines the interaction between strategic hydro reservoir operation and transmission capacity constraints, and summarizes the implications of market power for system reliability. A review of recent relevant literature is included. Finally, possible interventions to mitigate market power are analysed

Design and synthesis of pH-sensitive polyamino-ester magneto-dendrimers: Surface functional groups effect on viability of human prostate carcinoma cell lines DU145.

Science.gov (United States)

Dayyani, Nahid; Khoee, Sepideh; Ramazani, Ali

2015-06-15

Novel pH-sensitive, biocompatible and biodegradable magneto-dendrimers with OH and/or NH2 functional groups based on poly amino-ester were synthesized for delivery of anti-cancer drugs. Magnetite nanoparticles (MNPs) were synthesized by the co-precipitation method and their surfaces were modified by 3-aminopropyl triethoxysilane. The first and second generations of the magneto-dendrimer with hydroxyl end groups were produced by sequential acrylation and Michael addition reactions using the required amounts of acryloyl chloride and diethanolamine, respectively. The dendrimer containing amino functional surface groups up to second generation was synthesized by the same method using the necessary amounts of acryloyl chloride and ethylenediamine. These dendrimers were fully characterized by the Fourier transform infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA), dynamic light scattering (DLS) and zeta potential analysis, vibrating-sample magnetometer (VSM), scanning electron microscope (SEM), transmission electron microscopy (TEM) and selected area electron diffraction (SAED). In-vitro release profiles of the drug-loaded magnetic nanoparticles and their cytotoxicity assay were investigated at two pHs (7.4 and 5.8). The hydrolytic degradation behavior of magneto-dendrimers was evaluated in PBS buffer. Our research suggests that magneto-dendrimers having amine or hydroxyl functional groups could be considered as the suitable nanocarriers for therapy applications. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

Energy supply technologies. Hydro, ocean, wave and tidal

Energy Technology Data Exchange (ETDEWEB)

Fenhann, J.; Larsen, Hans [Risoe National Lab. - DTU (Denmark)

2007-11-15

This chapter presents an overview of current hydro, ocean, wave and tidal initiatives. Large hydro remains one of the lowest-cost generating technologies, although environmental constraints, resettlement impacts and the limited availability of sites have restricted further growth in many countries. Large hydro supplied 16 % of global electricity in 2004, down from 19 % a decade ago. Large hydro capacity totalled about 720 GW worldwide in 2004 and has grown historically at slightly more than 2 % annually. China installed nearly 8 GW of large hydro in 2004, taking the country to number one in terms of installed capacity (74 GW). With the completion of the Three Gorges Dam, China will add some 18.2 GW of hydro capacity in 2009. The socio-economic benefits of hydro include improved flood control and water supply. The socio-economic benefits of hydro include improved flood control and water supply. The socio-economic cost of hydro includes displacements and submergence. Further hydro can improve peak-capacity management. Ocean currents, some of which runs close to European coasts, carry a lot of kinetic energy. Part of this energy can be captured by sub-marine windmills and converted into electricity. These are more compact than the wind turbines used on land, simply because water is much denser than air. The main European countries with useful current power potential are France and the UK. Ocean tides are driven by the gravitational pull of the moon. With one high tide every 12 hours, a tidal power plant can operate for only four or five hours per cycle, so power from a single plant is intermittent. A suitably-designed tidal plant can, however, operate as a pimped storage system, using electricity during periods of low demand to store energy that can be recovered later. The only large, modern example of a tidal power plant is the 240 MW La Rance plant, built in France in the 1960s, which represents 91 % of the world tidal power capacity. Wave energy can be seen as

Solar Observations on Magneto-Convection

Science.gov (United States)

1989-05-31

Technical Library National Solar Observatory Sunspot, NM 88349 Karl - Schwarzschild -Strasse 1 8046 Garching bei Mundhen Solar Observations On Magneto...Schmidt, Hermann-Ulrich Schmidt, Hans-Christoph Thomas (eds.) Max-Planck-Institut fir Physik und Astrophysik Institut fiur Astrophysik Karl ... Schwarzschild -St-. 1 D-8046 Garching, FklG 14TIS CRiA.&l DTIC TA. U~Jar,iou8:ed B ......... ... Distribution I -- Availability COcý----- Avail and or Dist special

Magneto-Electric Dipole Antenna Arrays

OpenAIRE

Gupta, Shulabh; Jiang, Li Jun; Caloz, Christophe

2014-01-01

A planar magneto-electric (ME) dipole antenna array is proposed and demonstrated by both full-wave analysis and experiments. The proposed structure leverages the infinite wavelength propagation characteristic of composite right/left-handed (CRLH) transmission lines to form high-gain magnetic radiators combined with radial conventional electric radiators, where the overall structure is excited by a single differential feed. The traveling-wave type nature of the proposed ME-dipole antenna enabl...

Hydro turbines: An introduction

International Nuclear Information System (INIS)

Gordon, J.L.

1993-01-01

The various types of hydraulic turbines currently used in hydroelectric power plants are described. The descriptions are intended for use by non-engineers who are concerned with fish passage and fish mortality at a hydro power facility. Terminology used in the hydro industry is explained. Since the extent of cavitation is one of the factors affecting mortality rates of fish passing through hydraulic turbines, an equation is introduced which measures the extent of cavitation likely to be experienced in a turbine. An example of how the cavitation index can be calculated is provided for two typical power plants. The relation between certain parameters of power plant operation and the extent of cavitation, and therefore of fish mortality, is illustrated. 2 refs., 14 figs

Architecture at Hydro-Quebec

Energy Technology Data Exchange (ETDEWEB)

1991-01-01

Architecture at Hydro-Quebec is concerned not only with combining function and aesthetics in designing buildings and other structures for an electrical utility, but also to satisfy technical and administrative needs and to help solve contemporary problems such as the rational use of energy. Examples are presented of Hydro-Quebec's architectural accomplishments in the design of hydroelectric power stations and their surrounding landscapes, thermal power stations, transmission substations, research and testing facilities, and administrative buildings. It is shown how some buildings are designed to adapt to local environments and to conserve energy. The utility's policy of conserving installations of historic value, such as certain pre-1930 power stations, is illustrated, and aspects of its general architectural policy are outlined. 20 figs.

Hydro-Quebec's buyback tariff

International Nuclear Information System (INIS)

Richard, J.C.

1992-01-01

Hydro-Quebec had an installed electric generation capacity of 25,682 MW in 1990, of which 23,927 MW was hydraulic. Of the 26 thermal power plants, 22 are in remote communities on islands or in the north part of the province. The utility's development plan predicts an annual growth in demand of 2.6% to reach ca 200 TWh in 2006; this demand would be reduced to ca 180 TWh by energy efficiency measures. To increase capacity, Hydro-Quebec can utilize the hydro generation potential of its large rivers, of which 18,000 MW is economically viable, and its small rivers. Of the 10,000 MW theoretical potential of the latter, a large fraction cannot be economically developed under existing conditions. The utility has a policy to purchase energy as a function of the price of fossil fuel. For wind energy, this price was 4.22 cents/kWh in 1991; this price will be increased annually according to the inflation index. In its isolated sites such as the Magdalen Islands, current costs of diesel-generated electricity are at least 5.5 cents/kWh. There are possibilities for installing wind plants in isolated regions but their automatic control systems need to be improved for achieving a larger utilization factor relative to diesel generation and their cost needs to be reduced. 1 tab

The HydroShare Collaborative Repository for the Hydrology Community

Science.gov (United States)

Tarboton, D. G.; Idaszak, R.; Horsburgh, J. S.; Ames, D. P.; Goodall, J. L.; Couch, A.; Hooper, R. P.; Dash, P. K.; Stealey, M.; Yi, H.; Bandaragoda, C.; Castronova, A. M.

2017-12-01

HydroShare is an online, collaboration system for sharing of hydrologic data, analytical tools, and models. It supports the sharing of, and collaboration around, "resources" which are defined by standardized content types for data formats and models commonly used in hydrology. With HydroShare you can: Share your data and models with colleagues; Manage who has access to the content that you share; Share, access, visualize and manipulate a broad set of hydrologic data types and models; Use the web services application programming interface (API) to program automated and client access; Publish data and models and obtain a citable digital object identifier (DOI); Aggregate your resources into collections; Discover and access data and models published by others; Use web apps to visualize, analyze and run models on data in HydroShare. This presentation will describe the functionality and architecture of HydroShare highlighting our approach to making this system easy to use and serving the needs of the hydrology community represented by the Consortium of Universities for the Advancement of Hydrologic Sciences, Inc. (CUAHSI). Metadata for uploaded files is harvested automatically or captured using easy to use web user interfaces. Users are encouraged to add or create resources in HydroShare early in the data life cycle. To encourage this we allow users to share and collaborate on HydroShare resources privately among individual users or groups, entering metadata while doing the work. HydroShare also provides enhanced functionality for users through web apps that provide tools and computational capability for actions on resources. HydroShare's architecture broadly is comprised of: (1) resource storage, (2) resource exploration website, and (3) web apps for actions on resources. System components are loosely coupled and interact through APIs, which enhances robustness, as components can be upgraded and advanced relatively independently. The full power of this paradigm is the

Periodic reversal of magneto-optic Faraday rotation on uniaxial birefringence crystal with ultrathin magnetic films

Directory of Open Access Journals (Sweden)

C. W. Su

2013-07-01

Full Text Available An experimental approach of inclined incidence magneto-optic Faraday effect observed in the polar plane is applied. Three samples containing ferromagnetic cobalt ultrathin films on a semiconductor zinc oxide (0001 single crystal substrate with in-plane and out-of-plane anisotropy are evaluated. Through the fine adjustment of crossed polarizers in the magneto-optic effect measurement completely recorded the detail optical and magneto-optical responses from the birefringent crystal substrate and the magnetic film, especially for the signal induced from the substrate with uniaxial optical axis. The angle dependency of interference phenomena periodically from the optical and magneto-optical responses is attributed to the birefringence even in the absence of a magnetic field. The new type of observation finds that the transmission Faraday intensity in the oblique incidence includes a combination of polarization rotations, which results from optical compensation from the substrate and magneto-optical Faraday effects from the film. The samples grown at different rates and examined by this method exhibit magnetic structure discriminations. This result can be applied in the advanced polarized-light technologies to enhance the spatial resolution of magnetic surfaces with microstructural information under various magnetic field direction.

Revitalizing the nuclear business at Ontario Hydro

International Nuclear Information System (INIS)

Talbot, K.

1994-01-01

Ontario Hydro, North America's largest electric power utility, with an installed capacity of 34,000 MW, has under gone a major restructuring over the past year to better align itself with a changing electricity market and evolving customer needs. The single largest new business unit within the new Ontario Hydro is Ontario Hydro Nuclear (OHN), responsible for engineering, operation and maintenance of the Corporation's 20 large nuclear units at three generating sites, OHN faces a significant challenge in returning Ontario's nuclear units to the world-leading performance levels they enjoyed in the past, particularly the older Pickering A and Bruce A plants. However, steady progress is being made as evidenced by improving peer reviews and overall capacity and financial performance

The political economy of Canadian hydro-electricity : between old provincial hydros and neoliberal regional energy regimes

International Nuclear Information System (INIS)

Netherton, A.

2007-01-01

In economic terms, hydro-electricity is considered as a quasi-staple, as it prone to the classic staples problem of excess capacity. However, neither water nor hydroelectricity in Canada is produced primarily for export markets. Hydroelectric systems are often thought of as politicized monopolies. This paper discussed changes that have occurred in hydroelectric organizations over time, as they have been governed by a formative mixed regime; postwar provincial hydro systems; a megaprojects regime; and an emerging sustainability regionalization regime. The origins of electricity generation and transmission in Canada were discussed, as well as the ecological footprint of large mega-projects on rivers. The development of provincial hydro monopolies during the mid- to late- twentieth century was also outlined, as well as the sustainability and regionalization regime that developed after 1990. During the mature staples period of the mid-century, rents in hydro-electric organizations were distributed through cheap rates to subsidize and facilitate the development of mass production and mass consumption. However, post-staples consumption has now replaced mass consumption, and demand side management is replacing earlier cheap power policies. Nonetheless, the lack of systematic integration of networks has led to inefficiencies. Provincial grids are now being integrated into interconnected North American regional networks regulated by the United States. It was concluded that the Canadian electricity regime is increasingly influenced by the the supranational role that the United States is playing in structuring markets. 83 refs

Magneto-caloric and magneto-resistive properties of La0.67Ca0.33-xSrxMnO3

International Nuclear Information System (INIS)

Reves Dinesen, Anders

2004-08-01

This thesis presents results of an experimental investigation of magneto-caloric and magneto-resistive properties of a series of polycrystalline Ca- and Sr-doped lanthanum manganites, La 0.67 Ca 0.33-x Sr x MnO 3 (0≤ x ≤ 0.33), with the perovskite structure. The samples consisted of sintered oxide powders prepared the glycine-nitrate combustion technique. The compounds were ferromagnetic and showed a Curie transition in the temperature range 267370 K (T C increased with increasing x). An analysis of the structural properties was carried out by means of x-ray diffraction and the Rietveld technique. The variation of the Ca/Sr ratio was found to cause a transition from orthorhombic to rhombohedral symmetry in the composition range 0.110 0.67 Ca 0.33-x Sr x MnO 3 samples was measured directly and indirectly (by means of magnetization measurements). All the samples showed a magnetocaloric effect in the vicinity of T C . A model for the mag-netocaloric effect based on Weiss mean field theory and classical theories for heat capacities was developed. The model provided reasonable predictions of the magneto-caloric properties of the samples. The compounds with low Sr content showed a magnetocaloric effect comparable to that of Gadolinium, the prototypical working material for magnetic refrigeration at room temperature. A less comprehensive part of the investigation regarded the magneto-resistive properties of the La 0.67 Ca 0.33-x Sr x MnO 3 system. It was found that th polycrystalline nature of the compounds played a decisive role for the magnetotransport properties. Characteristic grain boundary effects, such as a low-field magnetoresistance, which is absent in single-crystalline perovskites, were observed. The low-field effect is usually ascribed to spin-dependent scattering in grain boundaries. Qualitatively the results obtained for the La 0.67 Ca 0.33-x Sr x MnO 3 samples were consistent with this model. The resistivity contribution arising from the presence of

A non-commutative formula for the isotropic magneto-electric response

International Nuclear Information System (INIS)

Leung, Bryan; Prodan, Emil

2013-01-01

A non-commutative formula for the isotropic magneto-electric response of disordered insulators under magnetic fields is derived using the methods of non-commutative geometry. Our result follows from an explicit evaluation of the Ito derivative with respect to the magnetic field of the non-commutative formula for the electric polarization reported in Schulz-Baldes and Teufel (2012 arXiv:1201.4812v1). The quantization, topological invariance and connection to a second Chern number of the magneto-electric response are discussed in the context of three-dimensional, disordered, time-reversal or inversion symmetric topological insulators. (paper)

Magneto-electro-elastic buckling analysis of nonlocal curved nanobeams

Science.gov (United States)

Ebrahimi, Farzad; Reza Barati, Mohammad

2016-09-01

In this work, a size-dependent curved beam model is developed to take into account the effects of nonlocal stresses on the buckling behavior of curved magneto-electro-elastic FG nanobeams for the first time. The governing differential equations are derived based on the principle of virtual work and Euler-Bernoulli beam theory. The power-law function is employed to describe the spatially graded magneto-electro-elastic properties. By extending the radius of the curved nanobeam to infinity, the results of straight nonlocal FG beams can be rendered. The effects of magnetic potential, electric voltage, opening angle, nonlocal parameter, power-law index and slenderness ratio on buckling loads of curved MEE-FG nanobeams are studied.

Design, construction and operation of Ontario Hydro's CANDU plants

International Nuclear Information System (INIS)

Campbell, P.G.

1981-06-01

Ontario Hydro has been producing electricity commercially from nuclear power since 1968, using CANDU reactors which have proved enormously successful. The 206-MW Douglas Point station, nearly 10 times larger than the first Canadian power reactor, NPD-2, resulted from a cooperative effort between Atomic Energy of Canada Ltd., the provincial government of Ontario, and Ontario Hydro. This approach led to a basic working relationship between the parties, with Ontario Hydro acting as project manager and builder, and AECL acting as consultant with respect to the nuclear components. Before Douglas Point was fully commissioned Ontario Hydro was ready to commit itself to more nuclear stations, and work was started on the four-unit Pickering nuclear generating station. Multi-unit stations were adopted to achieve economies of scale, and the concept has been retained for all subsequent nuclear power plants constructed in the province. The organization of Ontario Hydro's project management, construction, and operation of nuclear generating stations is described. Performance of the existing stations and cost of the power they produce have been entirely acceptable

Suitable combination of noble/ferromagnetic metal multilayers for enhanced magneto-plasmonic biosensing.

Science.gov (United States)

Regatos, David; Sepúlveda, Borja; Fariña, David; Carrascosa, Laura G; Lechuga, Laura M

2011-04-25

We present a theoretical and experimental study on the biosensing sensitivity of Au/Co/Au multilayers as transducers of the magneto-optic surface-plasmon-resonance (MOSPR) sensor. We demonstrate that the sensing response of these magneto-plasmonic (MP) transducers is a trade-off between the optical absorption and the magneto-optical activity, observing that the MP multilayer with larger MO effect does not provide the best sensing response. We show that it is possible to design highly-sensitive MP transducers able to largely surpass the limit of detection of the conventional surface-plasmon-resonance (SPR) sensor. This was proved comparing the biosensing performance of both sensors for the label-free detection of short DNA chains hybridization. For this purpose, we used and tested a novel label-free biofunctionalization protocol based on polyelectrolytes, which increases the resistance of MP transducers in aqueous environments.

Thermo-dynamic analysis and simulation of a combined air and hydro energy storage (CAHES) system

International Nuclear Information System (INIS)

Bi, Xianyun; Liu, Pei; Li, Zheng

2016-01-01

Large-scale energy storage is essential for the stability of a grid, especially for those with large proportion of intermittent renewable energy sources. The efficiency of a conventional compressed air energy storage (CAES) technology is limited by compression heat loss and changing working conditions. In this manuscript, a combined air and hydro energy storage (CAHES) system is proposed, which realizes a higher exergy efficiency compared with conventional CAES systems by reducing compression heat losses and addressing issues of changing working conditions through thermal compensation from solar radiation. The configuration and two operating modes of the proposed CAHES system are firstly introduced, followed by theoretical analysis and numerical simulation under different operating modes to analyze system performances. Impacts of external and internal factors on the system performances are analyzed. The practical feasibility of the system is also investigated. Results show that the exergy efficiency of the system reaches approximately 50%, whilst the charging electricity ratio reaches over 80%. - Highlights: • A combined air and hydro energy storage system is proposed. • High exergy efficiency is achieved and consumption of fossil fuel is eliminated. • The system performance is affected by compression ratio and solar radiation.

Toronto Hydro annual report, 1992

International Nuclear Information System (INIS)

1993-01-01

Toronto Hydro is the electric utility serving about 219,000 customers in Toronto, Ontario. In 1992, the utility purchased 9.6 billion kWh of electricity from Ontario Hydro, down 3.6% from 1990. Energy sales totalled 9.2 billion kWh, down 4.1% from 1990. Retail electricity rates increased an average of 6.7% in 1992, in spite of an increase in Ontario Hydro's wholesale rate by 8.2%, due to better than anticipated financial results and cost-control measures. The decline in electricity purchases and sales are attributed to economic factors, which also contributed to an increase in the utility's provision for bad debts. The third year of a 13.8-kV conversion project was completed in 1992; this project is converting the existing 4 kV distribution system to the higher voltage since maintenance and repair of the existing system is costly and the equipment is becoming less reliable. New construction, refurbishing, and modernization of equipment were performed at a number of substations. Other improvements in 1992 are reported in the areas of management and engineering systems, personnel policies, work safety, and energy management. Financial statements are included. 11 figs., 4 tabs

Fabrication of Continuous Microfibers Containing Magnetic Nanoparticles by a Facile Magneto-Mechanical Drawing

Science.gov (United States)

Li, Jin-Tao; Jia, Xian-Sheng; Yu, Gui-Feng; Yan, Xu; He, Xiao-Xiao; Yu, Miao; Gong, Mao-Gang; Ning, Xin; Long, Yun-Ze

2016-09-01

A facile method termed magneto-mechanical drawing is used to produce polymer composite microfibers. Compared with electrospinning and other fiber spinning methods, magneto-mechanical drawing uses magnetic force generated by a permanent magnet to draw droplets of polymer/magnetic nanoparticle suspensions, leading to fabrication of composite microfibers. In addition, because of the rotating collector, it is easy to control the fiber assembly such as fibrous array in parallel or crossed fibrous structure. The general applicability of this method has also been proved by spinning different polymers and magnetic nanoparticles. The resultant fibers exhibit good superparamagnetic behavior at room temperature and ultrahigh stretchability (~443.8 %). The results indicate that magneto-mechanical drawing is a promising technique to fabricate magnetic and stretchable microfibers and devices.

Design and analysis of a magneto-rheological damper for an all terrain vehicle

Science.gov (United States)

Krishnan Unni, R.; Tamilarasan, N.

2018-02-01

A shock absorber design intended to replace the existing conventional shock absorber with a controllable system using a Magneto-rheological damper is introduced for an All Terrain Vehicle (ATV) that was designed for Baja SAE competitions. Suspensions are a vital part of an All Terrain Vehicles as it endures various surfaces and requires utmost attention while designing. COMSOL multi-physics software is used for applications that have coupled physics problems and is a unique tool that is used for the designing and analysis phase of the Magneto-rheological damper for the considered application and the model is optimized based on Taguchi using DOE software. The magneto-rheological damper is designed to maximize the damping force with the measured geometric constraints for the All Terrain Vehicle.

Distributionally robust hydro-thermal-wind economic dispatch

International Nuclear Information System (INIS)

Chen, Yue; Wei, Wei; Liu, Feng; Mei, Shengwei

2016-01-01

Highlights: • A two-stage distributionally robust hydro-thermal-wind model is proposed. • A semi-definite programing equivalent and its algorithm are developed. • Cases that demonstrate the effectiveness of the proposed model are included. - Abstract: With the penetration of wind energy increasing, uncertainty has become a major challenge in power system dispatch. Hydro power can change rapidly and is regarded as one promising complementary energy resource to mitigate wind power fluctuation. Joint scheduling of hydro, thermal, and wind energy is attracting more and more attention nowadays. This paper proposes a distributionally robust hydro-thermal-wind economic dispatch (DR-HTW-ED) method to enhance the flexibility and reliability of power system operation. In contrast to the traditional stochastic optimization (SO) and adjustable robust optimization (ARO) method, distributionally robust optimization (DRO) method describes the uncertain wind power output by all possible probability distribution functions (PDFs) with the same mean and variance recovered from the forecast data, and optimizes the expected operation cost in the worst distribution. Traditional DRO optimized the random parameter in entire space, which is sometimes contradict to the actual situation. In this paper, we restrict the wind power uncertainty in a bounded set, and derive an equivalent semi-definite programming (SDP) for the DR-HTW-ED using S-lemma. A delayed constraint generation algorithm is suggested to solve it in a tractable manner. The proposed DR-HTW-ED is compared with the existing ARO based hydro-thermal-wind economic dispatch (AR-HTW-ED). Their respective features are shown from the perspective of computational efficiency and conservativeness of dispatch strategies.

Development of a dynamic coupled hydro-geomechanical code and its application to induced seismicity

Science.gov (United States)

Miah, Md Mamun

This research describes the importance of a hydro-geomechanical coupling in the geologic sub-surface environment from fluid injection at geothermal plants, large-scale geological CO2 sequestration for climate mitigation, enhanced oil recovery, and hydraulic fracturing during wells construction in the oil and gas industries. A sequential computational code is developed to capture the multiphysics interaction behavior by linking a flow simulation code TOUGH2 and a geomechanics modeling code PyLith. Numerical formulation of each code is discussed to demonstrate their modeling capabilities. The computational framework involves sequential coupling, and solution of two sub-problems- fluid flow through fractured and porous media and reservoir geomechanics. For each time step of flow calculation, pressure field is passed to the geomechanics code to compute effective stress field and fault slips. A simplified permeability model is implemented in the code that accounts for the permeability of porous and saturated rocks subject to confining stresses. The accuracy of the TOUGH-PyLith coupled simulator is tested by simulating Terzaghi's 1D consolidation problem. The modeling capability of coupled poroelasticity is validated by benchmarking it against Mandel's problem. The code is used to simulate both quasi-static and dynamic earthquake nucleation and slip distribution on a fault from the combined effect of far field tectonic loading and fluid injection by using an appropriate fault constitutive friction model. Results from the quasi-static induced earthquake simulations show a delayed response in earthquake nucleation. This is attributed to the increased total stress in the domain and not accounting for pressure on the fault. However, this issue is resolved in the final chapter in simulating a single event earthquake dynamic rupture. Simulation results show that fluid pressure has a positive effect on slip nucleation and subsequent crack propagation. This is confirmed by

Ontario Hydro looks at security

International Nuclear Information System (INIS)

Green, B.J.; Kee, B.

1995-01-01

Ontario Hydro operates 20 CANDU reactors on three different sites. Since 1984, a review of security arrangements on all the sites has taken place on a five-yearly basis. The review process for 1995 is outlined. The three objectives were as follows: to assess current security threats and risks to the stations; to assess the adequacy of the existing programme to protect against current threats; by comparing the security programme against those of comparable entities to establish benchmarks for good practice as a basis for improvements at Ontario Hydro. Valuable insights gained through the review are listed. These could be useful to other utilities. (UK)

Magneto-optic properties and optical parameter of thin MnCo films

Directory of Open Access Journals (Sweden)

E Attaran Kakhki

2009-09-01

Full Text Available Having precise hysterics loop of thin ferroelectric and ferromagnetic layers for optical switching and optical storages are important. A hysterieses loop can be achieved from a phenomenon call the magneto-optic effect. The magneto-optic effect is the rotation of a linear polarized electromagnetic wave propagated through a ferromagnetic medium. When light is transmitted through a layer of magnetic material the result is called the Faraday effects and in the reflection mode Kerr effect. In the present work we prepared a thin layer of MnxCo3-xO4 (0≤ x ≤ 1 and a binary form of MnO/Co3O4 by the spray pyrolysis method. The films have been characterized by a special set up of magneto-optic hysterics loop plotter containing a polarized He- Ne laser beam and a special electronic circuit. Faraday rotation were measured for these films by hysterics loop plotter and their optical properties were also obtained by spatial software designed for this purpose according to Swane Poel theoretical method. The measurements show that the samples at diluted Mn study has are ferromagnetic and the magneto-optic rotation show a good enhance respect to the single Co layers. Also, the study has shown that the MnCo oxide layer have two different energy gaps and by increasing of Mn this energy decreases and fall to 0.13 eV.

Optimal hydro scheduling and offering strategies considering price uncertainty and risk management

International Nuclear Information System (INIS)

Catalão, J.P.S.; Pousinho, H.M.I.; Contreras, J.

2012-01-01

Hydro energy represents a priority in the energy policy of Portugal, with the aim of decreasing the dependence on fossil fuels. In this context, optimal hydro scheduling acquires added significance in moving towards a sustainable environment. A mixed-integer nonlinear programming approach is considered to enable optimal hydro scheduling for the short-term time horizon, including the effect of head on power production, start-up costs related to the units, multiple regions of operation, and constraints on discharge variation. As new contributions to the field, market uncertainty is introduced in the model via price scenarios and risk management is included using Conditional Value-at-Risk to limit profit volatility. Moreover, plant scheduling and pool offering by the hydro power producer are simultaneously considered to solve a realistic cascaded hydro system. -- Highlights: ► A mixed-integer nonlinear programming approach is considered for optimal hydro scheduling. ► Market uncertainty is introduced in the model via price scenarios. ► Risk management is included using conditional value-at-risk. ► Plant scheduling and pool offering by the hydro power producer are simultaneously considered. ► A realistic cascaded hydro system is solved.

Bioinspired fabrication of magneto-optic hierarchical architecture by hydrothermal process from butterfly wing

International Nuclear Information System (INIS)

Peng Wenhong; Hu Xiaobin; Zhang Di

2011-01-01

We developed a green solution to incorporate nano-Fe 3 O 4 into the hierarchical architecture of a natural butterfly wing, thus obtaining unique magneto-optic nanocomposites with otherwise unavailable photonic features. Morphological characterization and Fourier Transform Infrared-Raman Spectroscope measurements indicate the assembly of Fe 3 O 4 nanocrystallites. The magnetic and optical responses of Fe 3 O 4 /wing show a coupling effect between the biological structure and magnetic material. The saturation magnetization and coercivity values of the as-prepared magneto-optic architecture varied with change of subtle structure. Such a combination of nano-Fe 3 O 4 and natural butterfly wing might create novel magneto-optic properties, and the relevant ideas could inspire the investigation of magneto-optical devices. - Highlights: → We develop a green, easy controlled hydrothermal process to synthesize magnetite hierarchical architecture. → The optical response of Fe 3 O 4 /wing exhibits a coupling effect between the structure and material. → The saturation magnetization value is mediated by shape anisotropy and the stress of different subtle structure, which has provided unique insights into studying the mysterious magnetic property of magnetite.

A general one-dimension nonlinear magneto-elastic coupled constitutive model for magnetostrictive materials

International Nuclear Information System (INIS)

Zhang, Da-Guang; Li, Meng-Han; Zhou, Hao-Miao

2015-01-01

For magnetostrictive rods under combined axial pre-stress and magnetic field, a general one-dimension nonlinear magneto-elastic coupled constitutive model was built in this paper. First, the elastic Gibbs free energy was expanded into polynomial, and the relationship between stress and strain and the relationship between magnetization and magnetic field with the polynomial form were obtained with the help of thermodynamic relations. Then according to microscopic magneto-elastic coupling mechanism and some physical facts of magnetostrictive materials, a nonlinear magneto-elastic constitutive with concise form was obtained when the relations of nonlinear strain and magnetization in the polynomial constitutive were instead with transcendental functions. The comparisons between the prediction and the experimental data of different magnetostrictive materials, such as Terfenol-D, Metglas and Ni showed that the predicted magnetostrictive strain and magnetization curves were consistent with experimental results under different pre-stresses whether in the region of low and moderate field or high field. Moreover, the model can fully reflect the nonlinear magneto-mechanical coupling characteristics between magnetic, magnetostriction and elasticity, and it can effectively predict the changes of material parameters with pre-stress and bias field, which is useful in practical applications

Effective-medium theory for nonlinear magneto-optics in magnetic granular alloys: cubic nonlinearity

International Nuclear Information System (INIS)

Granovsky, Alexander B.; Kuzmichov, Michail V.; Clerc, J.-P.; Inoue, Mitsuteru

2003-01-01

We propose a simple effective-medium approach for calculating the effective dielectric function of a magnetic metal-insulator granular alloy in which there is a weakly nonlinear relation between electric displacement D and electric field E for both constituent materials of the form D i =ε i (0) E i +χ i (3) |E i | 2 E i . We assume that linear ε i (0) and cubic nonlinear χ i (3) dielectric functions are diagonal and linear with magnetization non-diagonal components. For such metal-insulator composite magneto-optical effects depend on a light intensity and the effective cubic dielectric function χ eff (3) can be significantly greater (up to 10 3 times) than that for constituent materials. The calculation scheme is based on the Bergman and Stroud-Hui theory of nonlinear optical properties of granular matter. The giant cubic magneto-optical nonlinearity is found for composites with metallic volume fraction close to the percolation threshold and at a resonance of optical conductivity. It is shown that a composite may exhibit nonlinear magneto-optics even when both constituent materials have no cubic magneto-optical nonlinearity

Interconnected hydro-thermal systems - Models, methods, and applications

DEFF Research Database (Denmark)

Hindsberger, Magnus

2003-01-01

to be performed where the uncertainty of the inflow to the hydro reservoirs is handled endogenously. In this model snow reservoirs have been added in addition to the hydro reservoirs. Using this new approach allows sampling based decomposition algorithms to be used, which have proved to be efficient in solving...

Magneto Transport of CVD Carbon in Artificial Opals

Science.gov (United States)

Wang, Lei; Yin, Ming; Arammash, Fauzi; Datta, Timir

2014-03-01

Magneto-transport of carbon inverse opal structures were investigated in the 2.5 to 300 K temperatures and magnetic fields in the 0-10T regime. Qualitatively, our observations lie between those reported by previous researchers. Over this temperature range, transport (in zero magnetic field) is non-metallic; the resistance decreased with rising temperature however the temperature dependent behavior is not activated, as observed with variable range hopping. In three-dimensions, such behavior can also be the result of weak localization and electron-electron interactions; in particular the change in conductivity is a polynomial in fractional powers of absolute temperature. At sub-helium temperature regimes the relative magneto resistance is measured to be ~ 0.1 percent per Tesla. Results of data analysis for several different scenarios will be reported. DOD award #60177-RT-H from the ARO.

Magnetic field induced augmented thermal conduction phenomenon in magneto-nanocolloids

International Nuclear Information System (INIS)

Katiyar, Ajay; Dhar, Purbarun; Nandi, Tandra; Das, Sarit K.

2016-01-01

Magnetic field induced augmented thermal conductivity of magneto-nanocolloids involving nanoparticles, viz. Fe_2O_3, Fe_3O_4, NiO and Co_3O_4 dispersed in different base fluids have been reported. Experiments reveal the augmented thermal transport under external applied magnetic field. A maximum thermal conductivity enhancement ∼114% is attained at 7.0 vol% concentration and 0.1 T magnetic flux density for Fe_3O_4/EG magneto-nanocolloid. However, a maximum ∼82% thermal conductivity enhancement is observed for Fe_3O_4/kerosene magneto-nanocolloid for the same concentration but relatively at low magnetic flux density (∼0.06 T). Thereby, a strong effect of fluid as well as particle physical properties on the chain formation propensity, leading to enhanced conduction, in such systems is observed. Co_3O_4 nanoparticles show insignificant effect on the thermal conductivity enhancement of MNCs due to their minimal magnetic moment. A semi-empirical approach has been proposed to understand the mechanism and physics behind the thermal conductivity enhancement under external applied magnetic field, in tune with near field magnetostatic interactions as well as Neel relaxivity of the magnetic nanoparticles. Furthermore, the model is able to predict the phenomenon of enhanced thermal conductivity as a function of physical parameters and shows good agreement with the experimental observations. - Highlights: • Heat conduction in magneto-nanocolloids augments tremendously under magnetic field. • Oxide nanoparticles of Fe, Ni and Co dispersed in variant base fluids are used. • Enhancement in heat conduction is due to the formation of thermally conductive chains. • Proposed semi-empirical model shows good agreement with the experimental results.

Magneto x-ray study of a gadolinium-iron amorphous alloy

International Nuclear Information System (INIS)

Keller, E.N.

1985-01-01

This work reports the measurement of the magnetic x-ray absorption of an amorphous Gd-Fe ferrimagnetic thin film. The Gd to Fe concentration in the sample was 1:4. The magnetic x-ray effect is the x-ray analog of magneto-optic absorption effects. Magneto x-ray effects arise when a solid has different indices of refraction for right and left circularly polarized x-rays. The difference in absorption of left and right circularly polarized x-rays is called the magneto x-ray absorption. This absorption is proportional to the net spin of the final state density of states. At the L3 edge, the main x-ray transition is from initial Gd(2p) core states to final Gd(5d) unoccupied states. Since the 5d states have a net spin polarization in ferromagnetic Gd, this experiment hoped to directly observe how that polarization changes for Gd in the alloy. The magneto x-ray absorption at the Gd L3 edge will be proportional to the sign and amount of the net spin polarization of the 5d electrons. The magnetic x-ray absorption coefficient was found to be at least 0.0005 smaller than the linear absorption coefficient at the Gd white line energy. This was measured for the amorphous alloy at room temperature. Lock-in techniques were used to obtain the small limit to the absorption. A simple model for the size of the magnetic x-ray absorption coefficient in Gd suggests that the Gd(5d) net spin polarization is less than 0.01 Bohr magnetons per atom

Magneto-optical Kerr spectroscopy of noble metals

Science.gov (United States)

Uba, L.; Uba, S.; Antonov, V. N.

2017-12-01

Magneto-optical (MO) response of the noble metals Cu, Ag, and Au in the joint experimental and ab initio theoretical study is reported. The magneto-optical polar Kerr effect (MOKE) spectra of the noble-metal films were measured with the high sensitivity in the applied magnetic field of 1.5 T over the photon energy range 0.74-5.8 eV. Complete set of the optical conductivity tensor elements was determined precisely from the MOKE and the optical spectra measured at the same energy points. The importance of the off-diagonal intraband Drude-type transitions is demonstrated explicitly for each noble metal and found to be a substantial contribution to the observed spectra. It is shown that the first-principles calculations using the spin-polarized fully relativistic Dirac linear-muffin-tin-orbital method with the inclusion of correlation effects by GGA+U approach reproduce well the experimental spectra and allow to explain the microscopic origin of the noble metals' magneto-optical response in terms of interband transitions. Although the energy band structures of Cu, Ag, and Au are very similar, there are some distinctive differences in bandwidths and the energy positions of the bands (especially in X and L symmetry points), mainly due to different spin-orbit splitting and differences in the spatial extent of 3 d , 4 d , and 5 d valence wave functions of noble metals. It was found that the small differences in the band positions lead to significant differences in the MO properties of three noble metals. Although the spin-orbit interaction in Au is about six times larger than in Cu, and approximately two times larger than in Ag, the absolute value of Kerr rotation in Au is of the same magnitude as in Cu and one order of magnitude smaller as compared to Ag. The sharp Kerr effect spectral peak in Ag is not due to the electronic interband transitions, but rather to the plasma-edge splitting. The band-by-band decomposition of the Cu, Ag, and Au MO spectra is presented and the

Development of Magneto-Resistive Angular Position Sensors for Space Applications

Science.gov (United States)

Hahn, Robert; Langendorf, Sven; Seifart, Klaus; Slatter, Rolf; Olberts, Bastian; Romera, Fernando

2015-09-01

Magnetic microsystems in the form of magneto- resistive (MR) sensors are firmly established in automobiles and industrial applications. They measure path, angle, electrical current, or magnetic fields. MR technology opens up new sensor possibilities in space applications and can be an enabling technology for optimal performance, high robustness and long lifetime at reasonable costs. In a recent assessment study performed by HTS GmbH and Sensitec GmbH under ESA Contract a market survey has confirmed that space industry has a very high interest in novel, contactless position sensors based on MR technology. Now, a detailed development stage is pursued, to advance the sensor design up to Engineering Qualification Model (EQM) level and to perform qualification testing for a representative pilot space application.The paper briefly reviews the basics of magneto- resistive effects and possible sensor applications and describes the key benefits of MR angular sensors with reference to currently operational industrial and space applications. The results of the assessment study are presented and potential applications and uses of contactless magneto-resistive angular sensors for spacecraft are identified. The baseline mechanical and electrical sensor design will be discussed. An outlook on the EQM development and qualification tests is provided.

Far-Infrared Magneto-Optical Studies in Germanium and Indium-Antimonide at High Intensities

Science.gov (United States)

Leung, Michael

Observations of nonlinear magneto-optical phenomena occurring in p-type Germanium and n-type Indium Antimonide are reported. These include multi-photon ionization of impurity states, and a new observation, the magneto-photon ionization of impurity states, and a new observation, the magneto-photon drag effect. A novel source of far-infrared radiation has been used. This source uses a pulsed CO(,2) LASER to optically pump a super-radiant cell, generating light with intensities up to 100 KW/cm('2) and wavelengths from 66 (mu)m to 496 (mu)m in a pulse of 150 nanoseconds duration. The Germanium samples were doped with Gallium, which is a shallow acceptor with an ionization potential of 11 meV. At liquid Helium temperature virtually all charge carriers are bound to acceptor sites. However, the high intensity radiation unexpectedly ionizes the acceptors. This is demonstrated through measurements of photoconductivity, transmission and the photo-Hall Effect. This observation is unexpected because the photon energy is one-fourth the ionization potential. Rate equations describing sequential multiphoton excitations are in agreement with the experimental results. The intermediate states are postulated to be acceptor exciton band states. Studies of the photoexcited mobility at 496 (mu)m suggest that at non-saturating levels of photoexcitation, the primary scattering mechanism of hot holes in Germanium is by neutral impurities. A new magneto-optical effect, the magneto-photon drag effect, has been studied in both Germanium and Indium Antimonide. This is simply the absorption of momentum by free carriers, from an incident photon field. It has been found that the mechanism for this effect is different in the two materials. In Germanium, the effect occurs when carriers make optical transitions from the heavy hole band to the light hole band. Thus, the magneto-optical behavior depends heavily upon the band structure. On the other hand, a modified Drude model (independent electron

Deconstructing hydro: the BC electricity sector in this decade

International Nuclear Information System (INIS)

Jaccard, M.

2001-01-01

This paper provided speculation regarding the world-wide trend to deregulate electric utilities with particular focus on power deregulation in British Columbia. The four main issues facing electricity reform in British Columbia are to determine if publicly-owned assets should be privatised, how to achieve competitive electricity commodity prices in a de-regulated generation market, to determine the extent to which customers will be allowed direct access to sellers of electricity, and to determine which changes in industry structure are needed to ensure that control over the common carrier does not hinder fair competition. BC Hydro recently issued a plan for the next decade entitled the Integrated Electricity Plan which suggests that almost all growth in supply on the Hydro system will be limited to a few large projects totalling 900 megawatts, to be owned and operated by either BC Hydro or by the Columbia Power Corporation, another Crown entity. This plan is in complete contrast to the evolution of the electricity industry nearly everywhere else in the world where demand growth is being met almost entirely by small- and medium-scale non-utility resources issuing from competitive markets with minimal public funding. This article looks at why BC Hydro will probably be transformed significantly, even dismantled, in the coming decade. The article begins with a section explaining the cause and effects of major changes in the world-wide electricity industry. This is followed by a section reviewing what BC Hydro did in the 1990s while reform was taking place. The article also describes what BC Hydro intends to do in the next decade and explores reasons why this outcome is unlikely. The final section of the article provides an alternative vision of BC Hydro's future over the next decade. 1 tab., 3 figs

Properties of Exchange Coupled All-garnet Magneto-Optic Thin Film Multilayer Structures

Science.gov (United States)

Nur-E-Alam, Mohammad; Vasiliev, Mikhail; Kotov, Viacheslav A.; Balabanov, Dmitry; Akimov, Ilya; Alameh, Kamal

2015-01-01

The effects of exchange coupling on magnetic switching properties of all-garnet multilayer thin film structures are investigated. All-garnet structures are fabricated by sandwiching a magneto-soft material of composition type Bi1.8Lu1.2Fe3.6Al1.4O12 or Bi3Fe5O12:Dy2O3 in between two magneto-hard garnet material layers of composition type Bi2Dy1Fe4Ga1O12 or Bi2Dy1Fe4Ga1O12:Bi2O3. The fabricated RF magnetron sputtered exchange-coupled all-garnet multilayers demonstrate a very attractive combination of magnetic properties, and are of interest for emerging applications in optical sensors and isolators, ultrafast nanophotonics and magneto-plasmonics. An unconventional type of magnetic hysteresis behavior not observed previously in magnetic garnet thin films is reported and discussed. PMID:28788043

Properties of Exchange Coupled All-garnet Magneto-Optic Thin Film Multilayer Structures

Directory of Open Access Journals (Sweden)

Mohammad Nur-E-Alam

2015-04-01

Full Text Available The effects of exchange coupling on magnetic switching properties of all-garnet multilayer thin film structures are investigated. All-garnet structures are fabricated by sandwiching a magneto-soft material of composition type Bi1.8Lu1.2Fe3.6Al1.4O12 or Bi3Fe5O12:Dy2O3 in between two magneto-hard garnet material layers of composition type Bi2Dy1Fe4Ga1O12 or Bi2Dy1Fe4Ga1O12:Bi2O3. The fabricated RF magnetron sputtered exchange-coupled all-garnet multilayers demonstrate a very attractive combination of magnetic properties, and are of interest for emerging applications in optical sensors and isolators, ultrafast nanophotonics and magneto-plasmonics. An unconventional type of magnetic hysteresis behavior not observed previously in magnetic garnet thin films is reported and discussed.

Ground-state magneto-optical resonances in cesium vapor confined in an extremely thin cell

International Nuclear Information System (INIS)

Andreeva, C.; Cartaleva, S.; Petrov, L.; Slavov, D.; Atvars, A.; Auzinsh, M.; Blush, K.

2007-01-01

Experimental and theoretical studies are presented related to the ground-state magneto-optical resonance observed in cesium vapor confined in an extremely thin cell (ETC), with thickness equal to the wavelength of the irradiating light. It is shown that utilization of the ETC allows one to examine the formation of a magneto-optical resonance on the individual hyperfine transitions, thus distinguishing processes resulting in dark (reduced absorption) or bright (enhanced absorption) resonance formation. We report experimental evidence of bright magneto-optical resonance sign reversal in Cs atoms confined in an ETC. A theoretical model is proposed based on the optical Bloch equations that involves the elastic interaction processes of atoms in the ETC with its walls, resulting in depolarization of the Cs excited state, which is polarized by the exciting radiation. This depolarization leads to the sign reversal of the bright resonance. Using the proposed model, the magneto-optical resonance amplitude and width as a function of laser power are calculated and compared with the experimental ones. The numerical results are in good agreement with those of experiment

Fouling in small hydro projects; Verschmutzung von Kleinwasserkraftwerken - Schlussbericht

Energy Technology Data Exchange (ETDEWEB)

Abgottspon, A.; Staubli, T.

2010-03-15

This comprehensive final report for the Swiss Federal Office of Energy (SFOE) takes a look at fouling problems encountered in small hydro installations. The report is based on ten interviews made with operators of small hydro power stations in Switzerland. A parallel project carried out in Germany is mentioned. A large variation in the degree of fouling in the various hydro power stations is noted. Sources such as leaves in autumn and algae are discussed, as are the various rinsing procedures used to clear the turbines of fouling. Power losses are discussed and measures that can be taken to prevent fouling are described. Measurements made at an installation in Freienstein, Switzerland, are presented and discussed. The report is completed with an appendix containing calculations, details on the Freienstein power plant and the results of interviews made with the ten hydro power installations examined.

Exchange bias and bistable magneto-resistance states in amorphous TbFeCo thin films

Energy Technology Data Exchange (ETDEWEB)

Li, Xiaopu, E-mail: xl6ba@virginia.edu; Ma, Chung T.; Poon, S. Joseph, E-mail: sjp9x@virginia.edu [Department of Physics, University of Virginia, Charlottesville, Virginia 22904 (United States); Lu, Jiwei [Department of Materials Science and Engineering, University of Virginia, Charlottesville, Virginia 22904 (United States); Devaraj, Arun [Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory, Richland, Washington 99352 (United States); Spurgeon, Steven R.; Comes, Ryan B. [Physical and Computational Sciences Directorate, Pacific Northwest National Laboratory, Richland, Washington 99352 (United States)

2016-01-04

Amorphous TbFeCo thin films sputter deposited at room temperature on thermally oxidized Si substrate are found to exhibit strong perpendicular magnetic anisotropy. Atom probe tomography, scanning transmission electron microscopy, and energy dispersive X-ray spectroscopy mapping have revealed two nanoscale amorphous phases with different Tb atomic percentages distributed within the amorphous film. Exchange bias accompanied by bistable magneto-resistance states has been uncovered near room temperature by magnetization and magneto-transport measurements. The exchange anisotropy originates from the exchange interaction between the ferrimagnetic and ferromagnetic components corresponding to the two amorphous phases. This study provides a platform for exchange bias and magneto-resistance switching using single-layer amorphous ferrimagnetic thin films that require no epitaxial growth.

Microstructural effects on the magnetic and magneto-transport properties of electrodeposited Ni nanowire arrays

International Nuclear Information System (INIS)

Chen, Shu-Fang; Wei, Hao Han; Liu, Chuan-Pu; Hsu, C Y; Huang, J C A

2010-01-01

The magnetic and magneto-transport properties of Ni nanowire (NW) arrays, fabricated by electrodeposition in anodic-aluminum-oxide (AAO) templates, have been investigated. The AAO pores have diameters ranging from 35 to 75 nm, and the crystallinity of the Ni NW arrays could change from poly-crystalline to single-crystalline with the [111] and [110] orientations based on the electrodeposition potential. Notably, double switching magnetization loops and double-peaked magnetoresistance curves were observed in [110]-oriented NWs. The crystalline orientation of the Ni NW arrays is found to influence the corresponding magnetic and magneto-transport properties significantly. These magnetic behaviors are dominated by the competition between the magneto-crystalline and shape anisotropy.

HydroPak: concept design and analysis of a packaged cross-flow turbine

International Nuclear Information System (INIS)

2004-01-01

This report summarises the findings of a project to complete the conceptual design and economic optimization of a modular standardised crossflow hydro-turbine. Details are given of the work to date, the comparison of HydroPak cost with conventional micro- and mini-hydro power costs, and the economic advantages of taking the ''packaged'' and ''standardised approaches'' to the design process. The market for mini-hydro turbines is discussed

Magneto-plasmonics as a tool for magnetic field sensing

Czech Academy of Sciences Publication Activity Database

Vlček, J.; Lesňák, M.; Pištora, J.; Otipka, P.; Sobota, Jaroslav

2013-01-01

Roč. 58, č. 9 (2013), s. 260-264 ISSN 0447-6441 Institutional support: RVO:68081731 Keywords : plasmon resonance * magneto-optics * sensors * response factors Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering

Hydro-Quebec's Strategic Plan 2002-2006 : summary

International Nuclear Information System (INIS)

2001-01-01

A corporate profile of Hydro-Quebec was presented and the strategy that the utility will adopt for the 2002-2006 period was summarized. The utility plans to maintain its service quality and sustain environmental quality while developing a world class enterprise. Quebec has adopted a heritage pool giving Quebec consumers access to a maximum of 165 TWh of electricity per year at an average commodity rate of 2.79 cents per kilowatt-hour, the lowest rate for such a large amount of energy in North America. Above that volume, supply for the Quebec market will be ensured through competitive bidding, leading to the signing of supply contracts based on market price. Hydro-Quebec's strategy reflects the business opportunities open to Hydro-Quebec given its traditional activities in the province, the restructuring of North American energy markets, and the emergence of Quebec as a major energy hub. The business opportunities come from the fact that demand for electricity in Quebec is growing and from the opening of markets close to Quebec. Investment outlook in hydroelectric generation and transmission also appears to be profitable. It is likely that investment will be needed to build infrastructure. Hydro-Quebec is also working with its qualified workforce to develop a world-class international activity base. tabs., figs

Pumped Storage Hydro Power Plant Cierny Vah

International Nuclear Information System (INIS)

Regula, E.

1998-01-01

In this leaflet the pump-storage power plant Cierny Vah is presented. A Cierny Vah pumped storage power plant (PSP) has been designed and built for providing the reliable and quality electric energy supply and for covering load changes of an electrification system. (ES). It is mainly the pumped storage hydro power plants plants which in our conditions are the sources operatively covering the sudden changes of the ES load from the ecological, economic but mainly from the operational point of view. The electric energy generation volume is not the primary standpoint but especially their control functions in the ES. During the building of the Cierny Vah PSP the peak operation with the daily accumulation, participation in frequency control and output in ES and the compensation function in ES were to be its main tasks. After putting it into operation by especially after its becoming independent of the Slovak ES in 1994 the static functions (energy generation from pumping, balance output reserves, daily control, ...) gave way to dynamic functions which gained greater importance. After interconnection of the ES with the UCPTE West European Association in which there are besides other things, the strict criteria for observing balance outputs, the main functions of PSPs are as follows: (1) Dynamic services for ES; (2) Dispatching reserve for the fall out of the greatest ES block; (3) Observing the foreign cooperation balance agreed; (4) Compensation of peaks and also of sudden daily load diagram reductions. Technical parameters of the upper and lower reservoir are described. The hydro power plant is a body lower reservoir. In it there are six vertical pumping aggregates in the three machine layout: the motor-generator - the turbine - the pump. Between the turbine and the pump there is a hydraulically controlled claw clutch engaging at rest and disengaging also during the aggregate operation. During pumping air is involved inside the turbine. The Francis turbines have a

Synthesis of Immunotargeted Magneto-plasmonic Nanoclusters

OpenAIRE

Wu, Chun-Hsien; Sokolov, Konstantin

2014-01-01

Magnetic and plasmonic properties combined in a single nanoparticle provide a synergy that is advantageous in a number of biomedical applications including contrast enhancement in novel magnetomotive imaging modalities, simultaneous capture and detection of circulating tumor cells (CTCs), and multimodal molecular imaging combined with photothermal therapy of cancer cells. These applications have stimulated significant interest in development of protocols for synthesis of magneto-plasmonic nan...

HydroViz: evaluation of a web-based tool for improving hydrology education

Science.gov (United States)

Habib, E.; Ma, Y.; Williams, D.; Sharif, H.; Hossain, F.

2012-02-01

HydroViz is a web-based, student-centered, highly visual educational tool designed to support active learning in the field of Engineering Hydrology. The development of HydroViz is informed by recent advances in hydrologic data, numerical simulations, visualization and web-based technologies. An evaluation study was conducted to determine the effectiveness of HydroViz, to examine the buy-in of the program, and to identify project components that need to be improved. A total of 182 students from seven freshmen and junior-/senior-level undergraduate classes in three universities participated in the study over the course of two semesters (spring 2010 and fall 2010). Data sources included homework assignments, online surveys, and informal interviews with students. Descriptive statistics were calculated for homework and the survey. Qualitative analysis of students' comments and informal interview notes were also conducted to identify ideas and patterns. HydroViz was effective in facilitating students' learning and understanding of hydrologic concepts and increasing related skills. Students had positive perceptions of various features of HydroViz and they believe that HydroViz fits well in the curriculum. The experience with HydroViz was somewhat effective in raising freshmen civil engineering students' interest in hydrology. In general, HydroViz tend to be more effective with students in junior- or senior-level classes than students in freshmen classes. There does not seem to be obvious differences between different universities. Students identified some issues that can be addressed to improve HydroViz. Future adaptation and expansion studies are under planning to scale-up the application and utility of HydroViz into various hydrology and water-resource engineering curriculum settings.

Your energy team : Hydro Mississauga 1998 annual report

International Nuclear Information System (INIS)

1999-01-01

An operational and financial review of Hydro Mississauga for fiscal year 1998 is presented. Hydro Mississauga has been serving the municipality of Mississauga, Ontario for the past 82 years. In 1998, Hydro Mississauga went through major restructuring to include a new competitive 'Services' Division which offers a wide range of competitive products and services. Despite deregulation and restructuring, quality of service was maintained and all-time performance records were set for company safety and system reliability. Operating costs were also cut and low rates continued. The residential rate freeze will be extended for a sixth straight year into 1999. Consolidated financial statements show that in 1998 Hydro Mississauga was 100 per cent debt free. One of the top priorities for the utility in 1998 was to get ready to deal with any problem that might arise as we roll over into the year 2000. The utility has completed an inventory of all computer software and equipment and has taken measures such as remediation, testing and getting vendor assurances. tabs., figs

Magnetic field effects on spectrally resolved lifetime of on-line oxygen monitoring using magneto-optic probes

Science.gov (United States)

Mermut, O.; Gallant, P.; Le Bouch, N.; Leclair, S.; Noiseux, I.; Vernon, M.; Morin, J.-F.; Diamond, K.; Patterson, M. S.; Samkoe, K.; Pogue, B.

2009-02-01

Multimodal agents that serve as both probes for contrast and light-activated effectors of cellular processes in diseased tissue were developed. These agents were introduced into multicellular tumor spheroids (3D tissue models) and in the chorioallantoic membrane (CAM) of a chicken embryo. The luminescence decay was examined using a novel technique involving a spectrally-resolved fluorescence lifetime apparatus integrated with a weak electromagnet. A spectrallyresolved lifetime setup was used to identify magneto-optic species sensitive to magnetic field effects and distinguish from background emissions. We demonstrate that the applied magnetic fields can alter reaction rates and product distribution of some dyes detected by time- and spectrally-resolved luminescence changes. We will discuss the use of exogenous magneto-optical probes taken up in tumors to both induce phototoxicity, a process that is governed by complex and dynamically evolving mechanisms involving reactive oxygen species, and monitor treatment progress. The magnetic field enhancement, measured over a range of weak fields (0-300 mT) is correlated to oxygenation and may be used to monitor dynamic changes occurring due to oxygen consumption over the course of photodynamic therapy. Such online measurements provide the possibility to derive real-time information about response to treatment via monitoring magnetic field enhancement/suppression of the time-resolved, spectrally-resolved luminescence of the probe at the site of the treatment directly. Magnetic perturbation of lifetime can serve as a status reporter, providing optical feedback of oxygen-mediated treatments in situ and allowing for real-time adjustment of a phototherapy treatment plan.

Giant magneto-resistance devices

CERN Document Server

Hirota, Eiichi; Inomata, Koichiro

2002-01-01

This book deals with the application of giant magneto-resistance (GMR) effects to electronic devices. It will appeal to engineers and graduate students in the fields of electronic devices and materials. The main subjects are magnetic sensors with high resolution and magnetic read heads with high sensitivity, required for hard-disk drives with recording densities of several gigabytes. Another important subject is novel magnetic random-access memories (MRAM) with non-volatile non-destructive and radiation-resistant characteristics. Other topics include future GMR devices based on bipolar spin transistors, spin field-effect transistors (FETs) and double-tunnel junctions.

AB INITIO calculations of magneto-optical effects

Czech Academy of Sciences Publication Activity Database

Kuneš, Jan; Oppeneer, P. M.

2002-01-01

Roč. 2, - (2002), s. 141-146 ISSN 1346-7948 R&D Projects: GA AV ČR IAA1010214 Institutional research plan: CEZ:AV0Z1010914 Keywords : electronic structure * ab initio calculation * polar magneto-optical Kerr effect * transitiom metal * uranium intermetallics * CrO 2 Subject RIV: BM - Solid Matter Physics ; Magnetism

Effect of magneto rheological damper on tool vibration during hard turning

Science.gov (United States)

Paul, P. Sam; Varadarajan, A. S.

2012-12-01

Recently, the concept of hard turning has gained considerable attention in metal cutting as it can apparently replace the traditional process cycle of turning, heat treating, and finish grinding for assembly of hard wear resistant steel parts. The present investigation aims at developing a magneto rheological (MR) fluid damper for suppressing tool vibration and promoting better cutting performance during hard turning. The magneto rheological Fluid acts as a viscoelastic spring with non-linear vibration characteristics that are controlled by the composition of the magneto rheological fluid, the shape of the plunger and the electric parameters of the magnetizing field. Cutting experiments were conducted to arrive at a set of electrical, compositional and shape parameters that can suppress tool vibration and promote better cutting performance during turning of AISI 4340 steel of 46 HRC with minimal fluid application using hard metal insert with sculptured rake face. It was observed that the use of MR fluid damper reduces tool vibration and improves the cutting performance effectively. Also commercialization of this idea holds promise to the metal cutting industry.

The power of commitment : Newfoundland and Labrador Hydro 2000 annual report

International Nuclear Information System (INIS)

2000-01-01

A consolidated review of the operations of Newfoundland and Labrador Hydro (Hydro) was presented with particular focus on energy production, energy sales, the Avalon Transmission upgrade, development of the Granite Canal and Hydro's dam safety program. Hydro reported a 4.5 per cent increase in gross energy production at their generating plants throughout the system. Production from hydro sources also increased by 4.5 per cent to a total of 5,032 GWh. Thermal production from the Holyrood generating facility also increased slightly to 1,040 GWh. Production for peaking and emergency requirements from gas turbines and diesel plants dropped to 0.6 GWh. In 2000, about 83 per cent of all the energy supplied to their customers came from hydro sources. Total energy sales were up 4.6 per cent during 2000. This annual report presented the company's financial performance, executive changes, rural rate inquiry, and reorganization. Financial statements included a thorough review and analysis of financial transactions, the auditor's report, and the customary notes to the consolidated financial statement including balance sheets, assets, liabilities and capital. tabs., figs

Magneto-Rayleigh-Taylor instability driven by a rotating magnetic field

Science.gov (United States)

Duan, Shuchao; Xie, Weiping; Cao, Jintao; Li, Ding

2018-04-01

In this paper, we analyze theoretically the magneto-Rayleigh-Taylor instability driven by a rotating magnetic field. Slab configurations of finite thickness are treated both with and without using the Wenzel-Kramers-Brillouin approximation. Regardless of the slab thickness, the directional rotation of the driving magnetic field contributes to suppressing these instabilities. The two factors of the finite thickness and directional rotation of the magnetic field cooperate to enhance suppression, with the finite thickness playing a role only when the orientation of the magnetic field is time varying. The suppression becomes stronger as the driving magnetic field rotates faster, and all modes are suppressed, in contrast to the case of a non-rotating magnetic field, for which the vertical mode cannot be suppressed. This implies that the dynamically alternate configuration of a Theta-pinch and a Z-pinch may be applicable to the concept of Theta-Z liner inertial fusion.

Polycrystalline La1-xSrxMnO3 films on silicon: Influence of post-Deposition annealing on structural, (Magneto-)Optical, and (Magneto-)Electrical properties

Science.gov (United States)

Thoma, Patrick; Monecke, Manuel; Buja, Oana-Maria; Solonenko, Dmytro; Dudric, Roxana; Ciubotariu, Oana-Tereza; Albrecht, Manfred; Deac, Iosif G.; Tetean, Romulus; Zahn, Dietrich R. T.; Salvan, Georgeta

2018-01-01

The integration of La1-xSrxMnO3 (LSMO) thin film technology into established industrial silicon processes is regarded as challenging due to lattice mismatch, thermal expansion, and chemical reactions at the interface of LSMO and silicon. In this work, we investigated the physical properties of thin La0.73Sr0.27MnO3 films deposited by magnetron sputtering on silicon without a lattice matching buffer layer. The influence of a post-deposition annealing treatment on the structural, (magneto-)optical, and (magneto-)electrical properties was investigated by a variety of techniques. Using Rutherford backscattering spectroscopy, atomic force microscopy, Raman spectroscopy, and X-ray diffraction we could show that the thin films exhibit a polycrystalline, rhombohedral structure after a post-deposition annealing of at least 700 °C. The dielectric tensor in the spectral range from 1.7 eV to 5 eV determined from spectroscopic ellipsometry in combination with magneto-optical Kerr effect spectroscopy was found to be comparable to that of lattice matched films on single crystal substrates reported in literature [1]. The values of the metal-isolator transition temperature and temperature-dependent resistivities also reflect a high degree of crystalline quality of the thermally treated films.

The magneto-optical properties of non-uniform graphene nanoribbons

Science.gov (United States)

Chung, Hsien-Ching; Lin, Ming-Fa

2015-03-01

When synthesizing few-layer graphene nanoribbons (GNRs), non-uniform GNRs would be made simultaneously. Recently, the non-uniform GNRs, which is a stack of two GNRs with unequal widths, have been fabricated by mechanically exfoliated from bulk graphite. Some theoretical predictions have been reported, such as gap opening and transport properties. Under the influence of magnetic fields, magnetic quantization takes place and drastically changes the electronic properties. By tuning the geometric configuration, four categories of magneto-electronic spectra are exhibited. (1) The spectrum is mostly contributed by quasi-Landau levels (QLLs) of monolayer GNRs. (2) The spectrum displays two groups of QLLs, and the non-uniform GNR behaves like a bilayer one. (3) An intermediate category, the spectrum is composite disordered. (4) The spectrum presents the coexistence of monolayer and bilayer spectra. In this work, the magneto-electronic and optical properties for different geometric configurations are given, such as energy dispersions, density of states, wave functions, and magneto-absorption spectra are presented. Furthermore, the transformation between monolayer and bilayer spectra as well as the coexistence of monolayer and bilayer spectra are discussed in detail. One of us (Hsien-Ching Chung) thanks Ming-Hui Chung and Su-Ming Chen for financial support. This work was supported in part by the National Science Council of Taiwan under Grant Number 98-2112-M-006-013-MY4.

Heuristic Enhancement of Magneto-Optical Images for NDE

Science.gov (United States)

Cacciola, Matteo; Megali, Giuseppe; Pellicanò, Diego; Calcagno, Salvatore; Versaci, Mario; Morabito, FrancescoCarlo

2010-12-01

The quality of measurements in nondestructive testing and evaluation plays a key role in assessing the reliability of different inspection techniques. Each different technique, like the magneto-optic imaging here treated, is affected by some special types of noise which are related to the specific device used for their acquisition. Therefore, the design of even more accurate image processing is often required by relevant applications, for instance, in implementing integrated solutions for flaw detection and characterization. The aim of this paper is to propose a preprocessing procedure based on independent component analysis (ICA) to ease the detection of rivets and/or flaws in the specimens under test. A comparison of the proposed approach with some other advanced image processing methodologies used for denoising magneto-optic images (MOIs) is carried out, in order to show advantages and weakness of ICA in improving the accuracy and performance of the rivets/flaw detection.

Analysis of the Hydro-Quebec development plan 1992-2010

International Nuclear Information System (INIS)

Bernard, J.-T.; Genest-Laplante, E.

1994-01-01

In November 1992, the Quebec provincial utility Hydro-Quebec presented its development plan for the 1992-2010 period and shortly thereafter introduced its 1993-1995 energy efficiency commitments. The plan is analyzed using a model that incorporates the main institutional features of electricity price setting. Two scenarios are constructed. The first incorporates Hydro-Quebec's electricity demand forecast and the second allows electricity demand to respond to its price. A comparative analysis shows that electricity demand in the province should increase faster than forecast by Hydro-Quebec until 2010. In fact, demand could exceed the predicted level by ca 16 TWh, or 8.6%. This larger increase is due to a fall in the real price of electricity, itself caused by a government imposed fall in the real unit cost of the utility's operation. This last constraint is the real challenge faced by Hydro-Quebec. 12 refs., 7 tabs

Full cost accounting for decision making at Ontario Hydro

International Nuclear Information System (INIS)

Plagiannakos, T.

1996-01-01

Ontario Hydro's approach to full cost accounting (FCA) was outlined in response to questions raised earlier, in another forum, regarding Ontario Hydro's views on FCA. FCA was defined as an evaluation framework (as opposed to an accounting system) which tries to account for the internal (private) as well as the external (environment and human health) costs and benefits and integrate them into business decisions. When the external impacts cannot be monetized, qualitative evaluations are used based on the damage costing approach, which Ontario Hydro prefers to the cost of control method recommended by its critics. In general, however, Ontario Hydro is not opposed to FCA in so far as it puts the Utility in a better position to make more informed decisions, improve environmental cost management, avoid future costs, enhance revenue, improve environmental quality, contribute to environmental policy, and contribute to sustainable development. 1 fig

Development of a NDI system using the magneto-optical method. 2. Remote sensing using the novel magneto-optical inspection system

International Nuclear Information System (INIS)

Lee, Jinyi; Shoji, Tetsuo

1999-01-01

A new remote sensing system using the magneto-optical method is developed for inspection of flaws introduced during service operation where routine inspection is difficult because of difficult inaccessibility to the components. Among the advantages of non-destructive inspection (NDI) based on the magneto-optical sensor are: real time inspection, elimination of electrical noise and high spatial resolution. Remote sensing of flaws is achieved using the basic principles of Faraday effect, optical permeability, and diffraction of a laser by the domain walls. This paper describes a novel remote NDI system using the principles of optics and LMF. The main characteristic of the system is that image data and LMF information can be obtained simultaneously. It is possible to carry out remote and high speed inspection of cracks from the intensity of reflected light, and to estimate the size of a crack effectively with their diverse data. The advantages of this NDI system are demonstrated using two specimens. (author)

Ultracold molecules for the masses: Evaporative cooling and magneto-optical trapping

Science.gov (United States)

Stuhl, B. K.

While cold molecule experiments are rapidly moving towards their promised benefits of precision spectroscopy, controllable chemistry, and novel condensed phases, heretofore the field has been greatly limited by a lack of methods to cool and compress chemically diverse species to temperatures below ten millikelvin. While in atomic physics these needs are fulfilled by laser cooling, magneto-optical trapping, and evaporative cooling, until now none of these techniques have been applicable to molecules. In this thesis, two major breakthroughs are reported. The first is the observation of evaporative cooling in magnetically trapped hydroxyl (OH) radicals, which potentially opens a path all the way to Bose-Einstein condensation of dipolar radicals, as well as allowing cold- and ultracold-chemistry studies of fundamental reaction mechanisms. Through the combination of an extremely high gradient magnetic quadrupole trap and the use of the OH Λ-doublet transition to enable highly selective forced evaporation, cooling by an order of magnitude in temperature was achieved and yielded a final temperature no higher than 5mK. The second breakthrough is the successful application of laser cooling and magneto-optical trapping to molecules. Motivated by a proposal in this thesis, laser cooling of molecules is now known to be technically feasible in a select but substantial pool of diatomic molecules. The demonstration of not only Doppler cooling but also two-dimensional magneto-optical trapping in yttrium (II) oxide, YO, is expected to enable rapid growth in the availability of ultracold molecules—just as the invention of the atomic magneto-optical trap stimulated atomic physics twenty-five years ago.

HydroPak: concept design and analysis of a packaged cross-flow turbine

Energy Technology Data Exchange (ETDEWEB)

NONE

2004-07-01

This report summarises the findings of a project to complete the conceptual design and economic optimization of a modular standardised crossflow hydro-turbine. Details are given of the work to date, the comparison of HydroPak cost with conventional micro- and mini-hydro power costs, and the economic advantages of taking the ''packaged'' and ''standardised approaches'' to the design process. The market for mini-hydro turbines is discussed.

Scheduling of head-dependent cascaded hydro systems: Mixed-integer quadratic programming approach

International Nuclear Information System (INIS)

Catalao, J.P.S.; Pousinho, H.M.I.; Mendes, V.M.F.

2010-01-01

This paper is on the problem of short-term hydro scheduling, particularly concerning head-dependent cascaded hydro systems. We propose a novel mixed-integer quadratic programming approach, considering not only head-dependency, but also discontinuous operating regions and discharge ramping constraints. Thus, an enhanced short-term hydro scheduling is provided due to the more realistic modeling presented in this paper. Numerical results from two case studies, based on Portuguese cascaded hydro systems, illustrate the proficiency of the proposed approach.

Effective-medium theory for nonlinear magneto-optics in magnetic granular alloys: cubic nonlinearity

Energy Technology Data Exchange (ETDEWEB)

Granovsky, Alexander B. E-mail: granov@magn.ru; Kuzmichov, Michail V.; Clerc, J.-P.; Inoue, Mitsuteru

2003-03-01

We propose a simple effective-medium approach for calculating the effective dielectric function of a magnetic metal-insulator granular alloy in which there is a weakly nonlinear relation between electric displacement D and electric field E for both constituent materials of the form D{sub i}={epsilon}{sub i}{sup (0)}E{sub i} +{chi}{sub i}{sup (3)}|E{sub i}|{sup 2}E{sub i}. We assume that linear {epsilon}{sub i}{sup (0)} and cubic nonlinear {chi}{sub i}{sup (3)} dielectric functions are diagonal and linear with magnetization non-diagonal components. For such metal-insulator composite magneto-optical effects depend on a light intensity and the effective cubic dielectric function {chi}{sub eff}{sup (3)} can be significantly greater (up to 10{sup 3} times) than that for constituent materials. The calculation scheme is based on the Bergman and Stroud-Hui theory of nonlinear optical properties of granular matter. The giant cubic magneto-optical nonlinearity is found for composites with metallic volume fraction close to the percolation threshold and at a resonance of optical conductivity. It is shown that a composite may exhibit nonlinear magneto-optics even when both constituent materials have no cubic magneto-optical nonlinearity.

HydroShare: A Platform for Collaborative Data and Model Sharing in Hydrology

Science.gov (United States)

Tarboton, D. G.; Idaszak, R.; Horsburgh, J. S.; Ames, D. P.; Goodall, J. L.; Couch, A.; Hooper, R. P.; Dash, P. K.; Stealey, M.; Yi, H.; Bandaragoda, C.; Castronova, A. M.

2017-12-01

HydroShare is an online, collaboration system for sharing of hydrologic data, analytical tools, and models. It supports the sharing of and collaboration around "resources" which are defined by standardized content types for data formats and models commonly used in hydrology. With HydroShare you can: Share your data and models with colleagues; Manage who has access to the content that you share; Share, access, visualize and manipulate a broad set of hydrologic data types and models; Use the web services application programming interface (API) to program automated and client access; Publish data and models and obtain a citable digital object identifier (DOI); Aggregate your resources into collections; Discover and access data and models published by others; Use web apps to visualize, analyze and run models on data in HydroShare. This presentation will describe the functionality and architecture of HydroShare highlighting its use as a virtual environment supporting education and research. HydroShare has components that support: (1) resource storage, (2) resource exploration, and (3) web apps for actions on resources. The HydroShare data discovery, sharing and publishing functions as well as HydroShare web apps provide the capability to analyze data and execute models completely in the cloud (servers remote from the user) overcoming desktop platform limitations. The HydroShare GIS app provides a basic capability to visualize spatial data. The HydroShare JupyterHub Notebook app provides flexible and documentable execution of Python code snippets for analysis and modeling in a way that results can be shared among HydroShare users and groups to support research collaboration and education. We will discuss how these developments can be used to support different types of educational efforts in Hydrology where being completely web based is of value in an educational setting as students can all have access to the same functionality regardless of their computer.

Small hydro in Africa

CSIR Research Space (South Africa)

Jonker Klunne, W

2011-10-01

Full Text Available hydro, the author has started an online database of small hydropower projects in eastern and southern Africa. The main aim of the database is to catalogue the current situation and to make that accessible to policymakers, project developers, as well...

Magnetic field induced augmented thermal conduction phenomenon in magneto-nanocolloids

Energy Technology Data Exchange (ETDEWEB)

Katiyar, Ajay, E-mail: ajay_cim@rediffmail.com [Research and Innovation Centre (DRDO), Indian Institute of Technology Madras Research Park, Chennai 600 113 (India); Department of Mechanical Engineering, Indian Institute of Technology Madras, Chennai 600 036 (India); Dhar, Purbarun, E-mail: purbarun@iitrpr.ac.in [Department of Mechanical Engineering, Indian Institute of Technology Madras, Chennai 600 036 (India); Nandi, Tandra, E-mail: tandra_n@rediffmail.com [Defence Materials and Stores Research and Development Establishment (DRDO), G.T. Road, Kanpur 208 013 (India); Das, Sarit K., E-mail: skdas@iitrpr.ac.in [Department of Mechanical Engineering, Indian Institute of Technology Madras, Chennai 600 036 (India)

2016-12-01

Magnetic field induced augmented thermal conductivity of magneto-nanocolloids involving nanoparticles, viz. Fe{sub 2}O{sub 3}, Fe{sub 3}O{sub 4}, NiO and Co{sub 3}O{sub 4} dispersed in different base fluids have been reported. Experiments reveal the augmented thermal transport under external applied magnetic field. A maximum thermal conductivity enhancement ∼114% is attained at 7.0 vol% concentration and 0.1 T magnetic flux density for Fe{sub 3}O{sub 4}/EG magneto-nanocolloid. However, a maximum ∼82% thermal conductivity enhancement is observed for Fe{sub 3}O{sub 4}/kerosene magneto-nanocolloid for the same concentration but relatively at low magnetic flux density (∼0.06 T). Thereby, a strong effect of fluid as well as particle physical properties on the chain formation propensity, leading to enhanced conduction, in such systems is observed. Co{sub 3}O{sub 4} nanoparticles show insignificant effect on the thermal conductivity enhancement of MNCs due to their minimal magnetic moment. A semi-empirical approach has been proposed to understand the mechanism and physics behind the thermal conductivity enhancement under external applied magnetic field, in tune with near field magnetostatic interactions as well as Neel relaxivity of the magnetic nanoparticles. Furthermore, the model is able to predict the phenomenon of enhanced thermal conductivity as a function of physical parameters and shows good agreement with the experimental observations. - Highlights: • Heat conduction in magneto-nanocolloids augments tremendously under magnetic field. • Oxide nanoparticles of Fe, Ni and Co dispersed in variant base fluids are used. • Enhancement in heat conduction is due to the formation of thermally conductive chains. • Proposed semi-empirical model shows good agreement with the experimental results.

Vibration analysis of a hydro generator for different operating regimes

Science.gov (United States)

Haţiegan, C.; Pădureanu, I.; Jurcu, M.; Nedeloni, M. D.; Hamat, C. O.; Chioncel, C. P.; Trocaru, S.; Vasile, O.; Bădescu, O.; Micliuc, D.; (Filip Nedeloni, L.; Băra, A.; (Barboni Haţiegan, L.

2017-01-01

Based on experimental measurements, this paper presents the vibration analysis of a hydro generator that equips a Kaplan hydraulic turbine of a Hydropower plant in Romania. This analysis means vibrations measurement to different operating regimes of the hydro generator respectively before installing it and into operation, namely putting off load mode (unexcited and excited) respectively putting on load mode. By comparing, through the experimental results obtained before and after the operation of hydro aggregates are observed vibrations improvements.

Magneto-optic Doppler analyzer: a new instrument to measure mesopause winds

Science.gov (United States)

Williams, Bifford P.; Tomczyk, Steven

1996-11-01

The magneto-optic Doppler analyzer (MODA) is a new type of passive optical instrument that one can use to measure the Doppler shift of the sodium nightglow emitted at approximately 91 km near the mesopause. From this measurement, horizontal wind signatures are inferred. The MODA is based on a sodium vapor magneto-optic filter that provides inherent wavelength stability at a low cost. The instrument has been used to take nightly zonal and meridional wind measurements since October 1994 at Niwot Ridge, Colorado (40 N, 105 W). We obtained an internally consistent wind signal and measured the semidiurnal tide for several seasons.

BLUE GOLD: HYDRO-ELECTRIC RENT IN CANADA

OpenAIRE

Glenn Jenkins; RICHARD ZUKER

1984-01-01

In this study, an attempt is made to develop estimates of the value of economic rent from production of hydro-electricity. These estimates are made for the year 1979, which is the latest period for which a comprehensive set of data was available at the time this work was undertaken. The estimates are developed for the hydro-electricity generated (or used) by electric utilities in four provinces: Quebec (including Churchill Falls), Ontario, Manitoba and British Columbia. These electric systems...

More than energy: Ontario Hydro final annual report, January 1998 - March 1999

International Nuclear Information System (INIS)

1999-01-01

Ontario Hydro ceased operations on March 31, 1999 and its assets and functions were transferred by provincial statute to two successor corporations: Ontario Power Generation Corp. (OPG) and Ontario Hydro Services Inc. Its functions were also transferred to the Independent Electricity Market Operator and the Electrical Safety Authority, two not-for-profit agencies. The original act defining Ontario Hydro was replaced by the Energy Competition Act, 1998. Until the demerger of the company on April 1, 1999, Ontario Hydro served 108 direct industrial clients, almost one million retail clients and 255 municipal utilities. Ontario Power Generation inherited Ontario Hydro's generating portfolio, making it one of the largest power producers in North America in terms of installed capacity. The OPG system includes 69 hydroelectric stations, three nuclear sites, and six operating fossil fueled stations. Total installed system capacity is approximately 31,000 megawatts, and Ontario Hydro's total sales in 1998 were almost 139 terawatt hours. Ontario Hydro Services Company is an energy services-based transmission and distribution company. It owns and maintains 29,000 km of transmission lines, 114,700 km of distribution lines, 245 km of high-voltage underground cable, 256 transformer stations, 928 distribution and regulation stations, and 250 microwave stations. It also retains the retail business held by Ontario Hydro, which serves over 950,000 clients, and the transmission and generating business for 23 remote communities in Northern Ontario

Micro-hydro power: reviewing an old concept

Energy Technology Data Exchange (ETDEWEB)

Alward, R.; Eisenbart, S.; Volkman, J.

1979-01-01

This informaion package has been prepared to respond to an increasing number of requests for information on micro-hydro systems. It contains a resource directory, which is an attempt to put the reader in contact with the literature, plans, people, and companies appropriate to needs. On a world-wide basis, small-scale, environmentally benign, mechanical, and electrical hydropower systems are common. These are the systems for individual homes, farm, and shop use and generally have power outputs less than 100 kW. For convenience in terminology, this scale of hydro power is referred to as micro-hydro. A decision tree is first presented followed by information on determining the suitability of th site, equipment, economics, sources for financial assistance, regulatory conflicts, cautions and suggestions for the Do-It-Yourselfer, and the Self-Installer, manufacturers and suppliers, and sources of professional services. An annotated bibliography of 16 references is provided. (MCW)

A study of unsteady physiological magneto-fluid flow and heat transfer through a finite length channel by peristaltic pumping.

Science.gov (United States)

Tripathi, Dharmendra; Bég, O Anwar

2012-08-01

Magnetohydrodynamic peristaltic flows arise in controlled magnetic drug targeting, hybrid haemodynamic pumps and biomagnetic phenomena interacting with the human digestive system. Motivated by the objective of improving an understanding of the complex fluid dynamics in such flows, we consider in the present article the transient magneto-fluid flow and heat transfer through a finite length channel by peristaltic pumping. Reynolds number is small enough and the wavelength to diameter ratio is large enough to negate inertial effects. Analytical solutions for temperature field, axial velocity, transverse velocity, pressure gradient, local wall shear stress, volume flowrate and averaged volume flowrate are obtained. The effects of the transverse magnetic field, Grashof number and thermal conductivity on the flow patterns induced by peristaltic waves (sinusoidal propagation along the length of channel) are studied using graphical plots. The present study identifies that greater pressure is required to propel the magneto-fluid by peristaltic pumping in comparison to a non-conducting Newtonian fluid, whereas, a lower pressure is required if heat transfer is effective. The analytical solutions further provide an important benchmark for future numerical simulations.

B.C. Hydro : 1997 annual report

International Nuclear Information System (INIS)

1997-01-01

Operating and financial information from B.C. Hydro for 1997 is presented. B.C. Hydro is the third largest electric utility in Canada. The utility generates between 43,000 and 54,000 gigawatt-hours of electricity annually. More than 80 per cent of the electricity is produced by major hydroelectric generating stations on the Columbia and Peace rivers. This report presents a picture of improved financial performance, details of all revenues and expenditures and capsule summaries of the Utility's operations. The report also addresses issues regarding strategic direction, local and international competition, and consultation and regulatory activities. tabs. and figs

Magneto-optic and electro-optic modulators

International Nuclear Information System (INIS)

Hutchinson, D.P.; Ma, C.H.; Price, T.R.; Staats, P.A.; Vander Sluis, K.L.

1982-01-01

An important aspect of the Faraday rotation diagnostic for tokamak plasma measurements has been the development of suitable polarization modulators for submillimeter wavelengths. The problems are to obtain high optical transmission and fast modulation frequencies. At ORNL we have developed both a magneto-optic and an electro-optic submillimeter-wave modulators. These devices have been operated at modulation frequencies of approximately 100 kHz and both have high transmission

Development of high, medium and low oil content hydro cyclones; Desenvolvimento de hidrociclones para altos, medios e baixos teores de oleo

Energy Technology Data Exchange (ETDEWEB)

Moraes, Carlos Alberto Capela; Marins, Luiz Philipe Martinez; Melo, Darley Carrijo de; Silva, Fabricio Soares da [Centro de Pesquisas da Petrobras (CENPES). Gerencia de Tecnologia de Processamento e Avaliacao de Petroleo (Brazil)], e-mails: capela@petrobras.com.br, philipe@petrobras.com.br, darley@petrobras.com.br, fabriciosoares@petrobras.com.br; Oliveira Junior, Joao Americo Aguirre [Engineering Simulation and Scientific Software (ESSS), Florianopolis, SC (Brazil)], e-mail: aguirre@esss.com.br; Souza, Marcos Aurelio de; Barca, Luiz Fernando [Universidade Federal de Itajuba. Instituto de Engenharia Mecanica, MG (Brazil)], e-mails: maurelio@unifei.edu.br, barca@unifei.edu.br; Souza, Adriana Margarida Rodrigues Ferreira de [Fundacao Gorceix (Brazil)], e-mail: adrianamargarida.gorceix@petrobras.com.br; Almeida, Cristina Santos de [Universidade Federal do Rio de Janeiro. Fundacao de Coordenacao de Projetos, Pesquisa e Estudos Tecnologicos (COPPETEC/UFRJ). Escola de Quimica, RJ (Brazil)], e-mail: cristinaalmeida.coppetec@petrobras.com.br

2008-12-15

This paper is intended to describe the steps and present the results of a Research and Development (P and D) project aimed at developing and qualifying hydro cyclones for oil and water primary separation by PETROBRAS. The hydro cyclones families for high, medium and low oil content, respectively named as ATO, MTO and BTO were developed in this project and are currently in the patent filing phase. The members of each one of them were initially conceived and analyzed by means of numeric simulations (CFD). The set-ups for these simulations were based on experimental investigation supplemental papers of the fluid-dynamics in hydro cyclones, with the use of Laser Doppler Anemometry (LDA and PIV) in acrylic models. After the selection of the geometries for optimum performance at the CFD, actual size steel prototypes were designed and built for each one of the aforementioned hydro cyclones families. It was also designed and built a two-skid mounted system and one control rack which comprise a Mobile Lab for Hydro cyclone Tests (LMTH, being the acronym in Portuguese) with which field tests were carried out (Buracica Field, Bahia) in the prototypes. As the last phase of the Research and Development (R and D) project, it was prepared a computer routine which allows the performance of a project of a compact separation system for any specific application, using the hydro cyclones of the families aforementioned in series in the streams rich in water. This routine enables, from the features of the fluids in the application in particular, to select the most appropriate hydro cyclone to be used, obtain their corresponding operating conditions and also to obtain an estimate of the minimum performance range expected in the application under analysis. (author)

Scheduling of head-dependent cascaded hydro systems: Mixed-integer quadratic programming approach

Energy Technology Data Exchange (ETDEWEB)

Catalao, J.P.S.; Pousinho, H.M.I. [Department of Electromechanical Engineering, University of Beira Interior, R. Fonte do Lameiro, 6201-001 Covilha (Portugal); Mendes, V.M.F. [Department of Electrical Engineering and Automation, Instituto Superior de Engenharia de Lisboa, R. Conselheiro Emidio Navarro, 1950-062 Lisbon (Portugal)

2010-03-15

This paper is on the problem of short-term hydro scheduling, particularly concerning head-dependent cascaded hydro systems. We propose a novel mixed-integer quadratic programming approach, considering not only head-dependency, but also discontinuous operating regions and discharge ramping constraints. Thus, an enhanced short-term hydro scheduling is provided due to the more realistic modeling presented in this paper. Numerical results from two case studies, based on Portuguese cascaded hydro systems, illustrate the proficiency of the proposed approach. (author)

Temperature dependence of the domain wall magneto-Seebeck effect: avoiding artifacts of lead contributions

Science.gov (United States)

Fernández Scarioni, Alexander; Krzysteczko, Patryk; Sievers, Sibylle; Hu, Xiukun; Schumacher, Hans W.

2018-06-01

We study the resistive and thermopower signatures of a single domain wall in a magnetic nanowire in the temperature range from 4 K to 204 K. The results are compared to the anisotropic magnetoresistance (AMR) and anisotropic magneto-Seebeck (AMS) data of the whole permalloy nanowire. The AMS ratio of the nanowire reveals a sign change at a temperature of 98 K, while the AMR ratio is positive over the complete temperature range. This behavior is also observed for the domain wall, allowing an attribution of the measured signatures to the domain wall magneto-Seebeck and domain wall magnetoresistive contributions. However, the observed zero crossing of the AMS ratio, in both types of measurements is not expected for permalloy, since the Mott formula predicts a temperature dependency of the AMS identical to the AMR. We discuss the origin of this behavior and can attribute it to the contributions of the lead and the protective platinum layer used in our devices. A correction scheme is presented and applied. Such contributions could also play a role in the analysis of magneto-Seebeck effects in other nanoscale devices, such as the tunnel magneto-Seebeck effect of magnetic tunnel junctions.

Fifteen years of radioactive waste management at Ontario Hydro

International Nuclear Information System (INIS)

Carter, T.J.; Rao, P.K.M.

1985-01-01

Ontario Hydro is a large Canadian utility producing 84% (7394 MWe) of the Nuclear Electricity generated in Canada. The low- and intermediate-level radioactive wastes generated by the Ontario Hydro program are currently being managed at the Bruce Nuclear Power Development with various volume reduction, packaging and interim storage systems. Ontario Hydro also owns and operates a radioactive waste transportation system. Studies are in progress for final disposal of these wastes in a suitable geology in Ontario. Since its inception in 1971, Ontario Hydro's radioactive waste management program has evolved into providing a full fledged radioactive waste management capability to the utility's two nuclear generation centres at Pickering and Bruce, and later in the decade, to Darlington. This paper summarizes the various developments in this program; highlights the major facilities both in-service and planned to be built; reviews the experiences gained over fifteen years of in-house waste management; and discusses the proposed reorientation towards ultimate disposal of these wastes. 2 refs., 8 figs., 1 tab

Simulación del comportamiento de diversos modelos de amortiguadores magneto-reológicos mediante Modelica

OpenAIRE

Arranz Iglesias, Javier

2011-01-01

El presente proyecto fin de carrera consta de 8 capítulos, siendo el primero de ellos la introducción. En el capítulo 2: Se introduce el sistema de suspensión, así como los elementos de los que consta y los tipos de sistemas atendiendo a diversas clasificaciones. En el capítulo 3: Se trata el amortiguador magneto-reológico, los fluidos magneto-reológicos y sus aplicaciones. En el capítulo 4: Se exponen los diferentes modelos de caracterización del comportamiento de los amortiguadores magneto-...

Environmental-impact assessment of hydro-power in Egypt

International Nuclear Information System (INIS)

Rashad, S.M.; Ismail, M.A.

2000-01-01

The environmental impact of energy production and use with the associated emissions of greenhouse gases, particularly CO 2 , has created much attention and growing concern at both national and international levels. In Egypt, efforts have been directed to incorporate the environment-protection issues within the overall planning of the energy sector, as appropriate to its national commitment and its techno-economic considerations. Over the past decade, 1985-1995, hydro-power had contributed between 28 and 22% of the total energy produced by Egyptian power-plants, while the contribution of the hydro capacity was between 32.4 and 21.5%. Many studies have been carried out on the impacts of the Aswan High Dam on various aspects of the environment. An objective evaluation of the Dam, based on 25 years of operational data, indicated that it has overall been positive even though it has contributed to some environmental problems. These problems, however, are significantly less than most people originally expected. This paper deals with the review and analysis of the detrimental effects of hydro-power in Egypt. An evaluation will be given of the emissions of greenhouse gases from the whole hydro-chain. (Author)

Design and modeling of semi-active squeeze film dampers using magneto-rheological fluids

International Nuclear Information System (INIS)

Kim, Keun-Joo; Lee, Chong-Won; Koo, Jeong-Hoi

2008-01-01

Conventional squeeze film dampers (SFDs) have shown their effectiveness in suppressing unbalanced vibrations in rotor systems, particularly supported by rolling element bearings. Recently, there is an increasing demand for 'controllable' SFDs to meet the need of modern rotating machinery, characterized by high operating speed and high load capacity. Thus, this paper presents a controllable semi-active SFD using magneto-rheological (MR) fluids, focusing on its design and modeling. It offers a comprehensive design method and an innovative experimental identification and modeling technique for MR-SFDs. The primary goal of the MR-SFD design is set to maximize its dynamic control bandwidth, and the design method includes the material selection, magnetic circuit analysis and sealing element design. After constructing a prototype MR-SFD based on the final design, this work investigated how some of the critical design parameters affect the performance of the MR-SFD (i.e. its dynamic control bandwidth change). Furthermore, it characterized the damper's dynamic behavior experimentally using a novel excitation method that adopts active magnetic bearing (AMB) units. Unlike conventional methods, the AMB system was able to precisely control the amplitude and frequency of the input excitation, enabling us to obtain the nonlinear dynamic stiffness properties of the MR-SFD with varying input current. In modeling the dynamic behavior of the MR-SFD, this study employed the describing function method. The describing function analysis effectively captured the nonlinear dynamic behavior of the MR-SFD

Hydro-Quebec proudly celebrates 50 years of service

International Nuclear Information System (INIS)

Anon.

1994-01-01

The history of the electric utility Hydro-Quebec is reviewed from its creation in 1944 as the Hydroelectric Commission of Quebec. The utility inherited an installed capacity of 696 MW and it first went about standardizing electricity supply conditions and establishing equal rates in the Montreal area. It began major construction projects in the mid-1950s with the Bersimis and Carillon hydroelectric plants. By 1962, installed capacity reached 3,657 MW. In 1963, Hydro-Quebec bought 10 private electricity distribution companies, 45 cooperatives, and a series of private or municipal systems. In 1965, the utility commissioned the world's first 735-kV transmission line. In 1967, Hydro-Quebec opened its research institute, and another laboratory specializing in electrotechnologies was opened in 1987. The 1970s were noted for the James Bay hydroelectric projects, the development of which was eventually governed by the landmark James Bay and Northern Quebec Agreement of 1975. Electricity exports greatly expanded in the 1970s and early 1980s as larger hydroelectric projects came on stream. Challenges of the 1990s include service quality, environmental issues, energy efficiency, and conservation. Hydro-Quebec's Energy Efficiency Project has a target of annual savings of 9.3 TWh by the year 2000. Energy efficiency and power system upgrading are priorities for serving future customer needs. Hydro-Quebec continues to promote hydroelectric power as the cheapest, most environmentally benign form of energy and future generating stations in progress include phase II of the LaGrande complex (to be completed 1996). 2 figs

Marginal-cost pricing for Hydro-Quebec residential customers

International Nuclear Information System (INIS)

Paquin, C.

1994-02-01

An option available to governments and to utilities such as Hydro-Quebec for responding to objectives of energy efficiency is the adoption of marginal cost pricing. Compared to currently used price structures, marginal cost pricing will allow improvement of price signals and assure an optimal utilization of the resource. That type of pricing could be economically beneficial but may not be desirable from the point of view of revenue distribution. Taking account of Hydro-Quebec's cost structure, pure marginal cost pricing would generate an income that would be strongly contested on equity grounds. For example, it would raise prices 60% for residential customers. Faced with this possibility, an analysis is presented of the impact of a peak-offpeak pricing (or pure marginal cost pricing) on Hydro-Quebec's residential customer energy bills. The marginal costs of Hydro-Quebec are calculated by the method of Bernard and Chatel (1985) and analysis of the results is based on Friedman and Weare (1993). A sample of 28,417 residential customers from a 1989 Hydro-Quebec survey is used in the study. Two scenarios are analyzed; the first allowing comparison of the energy bill only on the basis of marginal costs and of average costs, and the second allowing comparison of the impact of marginal cost pricing on the total bill. In the first scenario, the impact translates into a 31% increase in energy bills for the entire customer class considered; in addition, this impact is inversely proportional to the revenue class. In the second scenario, the increase is 24%. 33 refs., 10 figs., 53 tabs

Overview of SPH-ALE applications for hydraulic turbines in ANDRITZ Hydro

Science.gov (United States)

Rentschler, M.; Marongiu, J. C.; Neuhauser, M.; Parkinson, E.

2018-02-01

Over the past 13 years, ANDRITZ Hydro has developed an in-house tool based on the SPH-ALE method for applications in flow simulations in hydraulic turbines. The initial motivation is related to the challenging simulation of free surface flows in Pelton turbines, where highly dynamic water jets interact with rotating buckets, creating thin water jets traveling inside the housing and possibly causing disturbances on the runner. The present paper proposes an overview of industrial applications allowed by the developed tool, including design evaluation of Pelton runners and casings, transient operation of Pelton units and free surface flows in hydraulic structures.

Urban water-quality modelling: implementing an extension to Multi-Hydro platform for real case studies

Science.gov (United States)

Hong, Yi; Giangola-Murzyn, Agathe; Bonhomme, Celine; Chebbo, Ghassan; Schertzer, Daniel

2015-04-01

During the last few years, the physically based and fully distributed numerical platform Multi-Hydro (MH) has been developed to simulate hydrological behaviours in urban/peri-urban areas (El-Tabach et al. , 2009 ; Gires et al., 2013 ; Giangola-Murzyn et al., 2014). This hydro-dynamical platform is open-access and has a modular structure, which is designed to be easily scalable and transportable, in order to simulate the dynamics and complex interactions of the water cycle processes in urban or peri-urban environment (surface hydrology, urban groundwater infrastructures and infiltration). Each hydrological module relies on existing and widely validated open source models, such as TREX model (Velleux, 2005) for the surface module, SWMM model (Rossman, 2010) for the drainage module and VS2DT model (Lappala et al., 1987) for the soil module. In our recent studies, an extension of MH has been set up by connecting the already available water-quality computational components among different modules, to introduce a pollutant transport modelling into the hydro-dynamical platform. As for the surface module in two-dimensions, the concentration of particles in flow is expressed by sediment advection equation, the settling of suspended particles is calculated with a simplified settling velocity formula, while the pollutant wash-off from a given land-use is represented as a mass rate of particle removal from the bottom boundary over time, based on transport capacity, which is computed by a modified form of Universal Soil Loss Equation (USLE). Considering that the USLE is originally conceived to predict soil losses caused by runoff in agriculture areas, several adaptations were needed to use it for urban areas, such as the alterations of USLE parameters according to different criterions, the definition of the appropriate initial dust thickness corresponding to various land-uses, etc. Concerning the drainage module, water quality routing within pipes assumes that the conduit

Design and analysis of magneto rheological fluid brake for an all terrain vehicle

Science.gov (United States)

George, Luckachan K.; Tamilarasan, N.; Thirumalini, S.

2018-02-01

This work presents an optimised design for a magneto rheological fluid brake for all terrain vehicles. The actuator consists of a disk which is immersed in the magneto rheological fluid surrounded by an electromagnet. The braking torque is controlled by varying the DC current applied to the electromagnet. In the presence of a magnetic field, the magneto rheological fluid particle aligns in a chain like structure, thus increasing the viscosity. The shear stress generated causes friction in the surfaces of the rotating disk. Electromagnetic analysis of the proposed system is carried out using finite element based COMSOL multi-physics software and the amount of magnetic field generated is calculated with the help of COMSOL. The geometry is optimised and performance of the system in terms of braking torque is carried out. Proposed design reveals better performance in terms of braking torque from the existing literature.

A Novel Defect Inspection Method for Semiconductor Wafer Based on Magneto-Optic Imaging

Science.gov (United States)

Pan, Z.; Chen, L.; Li, W.; Zhang, G.; Wu, P.

2013-03-01

The defects of semiconductor wafer may be generated from the manufacturing processes. A novel defect inspection method of semiconductor wafer is presented in this paper. The method is based on magneto-optic imaging, which involves inducing eddy current into the wafer under test, and detecting the magnetic flux associated with eddy current distribution in the wafer by exploiting the Faraday rotation effect. The magneto-optic image being generated may contain some noises that degrade the overall image quality, therefore, in this paper, in order to remove the unwanted noise present in the magneto-optic image, the image enhancement approach using multi-scale wavelet is presented, and the image segmentation approach based on the integration of watershed algorithm and clustering strategy is given. The experimental results show that many types of defects in wafer such as hole and scratch etc. can be detected by the method proposed in this paper.

SQUID magnetometry and magneto-optics of epitaxial EuS

International Nuclear Information System (INIS)

Rumpf, K.; Granitzer, P.; Krenn, H.; Kellner, W.; Pascher, H.; Kirchschlager, R.; Janecek, S.

2004-01-01

The complicated (H,T)-magnetic phase diagram of EuS is caused by the critical balance between nearest and next nearest neighbour exchange interaction (J NN = 0.119 K and J NNN =-0.1209 K) and leads to various spin arrangements NNSS..., NSN..., NNS, NNN... [NS denotes opposite ferromagnetic order in adjacent (111) planes]. Beside the subtle local exchange of 5d-t 2g electrons and localized holes with neighbouring Eu-4f spins, obviously also the strain status influences the occurrence of these different phases. We investigate the magnetic ordering phenomenon in a strained 2.5 μm EuS film on BaF 2 substrate by SQUID magnetometry and magneto-optics like spectral Faraday- and Kerr-effect measurements for temperatures from 2 K up to 200 K and for magnetic field up to 5 T. The magneto-optical probe monitors the local environment of the photoexcited electron-hole pair, called magnetic exciton, located within a ferromagnetic surrounding (photoinduced magnetic polaron), whereas the integral magnetization measured by SQUID is most sensitive to long-range magnetic ordering. In spite of the dissimilarity of measurement techniques we find an influence of the long-range magnetic order (e.g. of the NNS- or NNN-matrix) on the non-resonant Kerr reflection. The complementarity of SQUID and magneto-optical methods is stringent only in the (resonant) spectral range, where magnetic polarons are formed. (author)

Jumping magneto-electric states of electrons in semiconductor multiple quantum wells

International Nuclear Information System (INIS)

Pfeffer, Pawel; Zawadzki, Wlodek

2011-01-01

Orbital and spin electron states in semiconductor multiple quantum wells in the presence of an external magnetic field transverse to the growth direction are considered. Rectangular wells of GaAs/GaAlAs and InAs/AlSb are taken as examples. It is shown that, in addition to magneto-electric states known from one-well systems, there appear magneto-electric states having a much stronger dependence of energies on a magnetic field and exhibiting an interesting anti-crossing behavior. The origin of these states is investigated and it is shown that the strong field dependence of the energies is related to an unusual 'jumping' behavior of their wavefunctions between quantum wells as the field increases. The ways of investigating the jumping states by means of interband magneto-luminescence transitions or intraband cyclotron-like transitions are considered and it is demonstrated that the jumping states can be observed. The spin g factors of electrons in the jumping states are calculated using the real values of the spin–orbit interaction and bands' nonparabolicity for the semiconductors in question. It is demonstrated that the jumping states offer a wide variety of the spin g factors

X-ray magneto-optic KERR effect studies of spring magnet heterostructures.

Energy Technology Data Exchange (ETDEWEB)

Kortright, J. B.; Kim, S.-K.; Fullerton, E. E.; Jiang, J. S.; Bader, S. D.

2000-11-01

The complex 3-dimensional magnetization reversal behavior of Sin-Co/Fe exchange spring films is used to test the sensitivity of different resonant soft x-ray magneto-optical Kerr effect (MOKE) measurements to changes in longitudinal and transverse moments within the SOIIFe layer and to changes in these moments in depth within the Fe layer. As in the visible MOKE, changes in longitudinal and net transverse moments are resolved by measuring both Kerr rotation and intensity loops in the near the Fe 2p core resonance. These x-ray MOKE signals measured using linear incident polarization are more directly interpreted in terms of longitudinal and transverse moments than are the same signals measured using elliptical polarization. Varying photon energy near the Fe L3line is shown to be an effective means of resolving distinctly different reversal behavior at the top and bottom of the 20 nm thick Fe layer resulting from the strong exchange coupling at the Sin-Co/Fe interface. Measured x-ray MOKE spectra and signals are in qualitative agreement with those calculated using standard magneto-optical formalisms incorporating interference between different layers and measured helicity-dependent magneto-optical constants for Fe.

A magneto-rheological fluid mount featuring squeeze mode: analysis and testing

International Nuclear Information System (INIS)

Chen, Peng; Bai, Xian-Xu; Qian, Li-Jun; Choi, Seung-Bok

2016-01-01

This paper presents a mathematical model for a new semi-active vehicle engine mount utilizing magneto-rheological (MR) fluids in squeeze mode (MR mount in short) and validates the model by comparing analysis results with experimental tests. The proposed MR mount is mainly comprised of a frame for installation, a main rubber, a squeeze plate and a bobbin for coil winding. When the magnetic fields on, MR effect occurs in the upper gap between the squeeze plate and the bobbin, and the dynamic stiffness can be controlled by tuning the applied currents. Employing Bingham model and flow properties between parallel plates of MR fluids, a mathematical model for the squeeze type of MR mount is formulated with consideration of the fluid inertia, MR effect and hysteresis property. The field-dependent dynamic stiffness of the MR mount is then analyzed using the established mathematical model. Subsequently, in order to validate the mathematical model, an appropriate size of MR mount is fabricated and tested. The field-dependent force and dynamic stiffness of the proposed MR mount are evaluated and compared between the model and experimental tests in both time and frequency domains to verify the model efficiency. In addition, it is shown that both the damping property and the stiffness property of the proposed MR mount can be simultaneously controlled. (paper)

PCB management at Manitoba Hydro's Waverley Service Centre

International Nuclear Information System (INIS)

Rempel, R.G.; Engstrom, T.

1996-01-01

Manitoba Hydro was the first Canadian utility to initiate a program to decontaminate insulating oil contaminated with polychlorinated biphenyls (PCBs). This paper describes Manitoba Hydro's recovery, reuse and recycling program, operated out of the utility's Waverley Service Centre (WSC). The WSC is a central facility serving to phase out and and destroy PCBs which remain in Manitoba Hydro's electrical system. Several hundred thousand litres of PCB-contaminated insulating oil are decontaminated annually at the WSC. The decontaminated oil is then reconditioned for reuse within the system operations. A PCBX unit was purchased from Sun Ohio for the decontamination of insulating oils containing PCBs. PCB decontamination is achieved through a chemical dechlorination treatment process. The PCBX treatment unit and the PCB storage building were described. 18 refs., 8 figs

Higher profits, lower bills : a new electricity strategy for Hydro-Quebec

International Nuclear Information System (INIS)

2010-01-01

Quebec is the fourth largest producer of hydro-electricity in the world, and has among the lowest electricity rates in North America. In 2008, 89 percent of the electricity produced by Hydro-Quebec was sold in the province, and the remainder was exported. In 2009, the electric utility released its strategic plan for 2009 to 2013. Hydro-Quebec's net profits are forecast to decline by 24 percent by 2013 and electricity rates are forecast to rise by 8.5 percent. Since Hydro-Quebec has already developed all of the province's low-cost hydroelectric resources, it can no longer increase profits and lower rates by building new hydropower production stations. In order to continue to prosper, the utility will invest in energy efficiency and better coordination of its power system with Ontario's. Increased electricity exports from Hydro-Quebec will help both Ontario and the United States reduce their greenhouse gas emissions by displacing fossil power generation. 25 refs., 2 tabs., 3 figs.

ENVIRONMENTAL TECHNOLOGY VERIFICATION: JOINT (NSF-EPA) VERIFICATION STATEMENT AND REPORT HYDRO COMPLIANCE MANAGEMENT, INC. HYDRO-KLEEN FILTRATION SYSTEM, 03/07/WQPC-SWP, SEPTEMBER 2003

Science.gov (United States)

Verification testing of the Hydro-Kleen(TM) Filtration System, a catch-basin filter designed to reduce hydrocarbon, sediment, and metals contamination from surface water flows, was conducted at NSF International in Ann Arbor, Michigan. A Hydro-Kleen(TM) system was fitted into a ...

How would the privatization of Hydro-Quebec make Quebecers richer?

International Nuclear Information System (INIS)

Garcia, C.

2009-02-01

In 1962, a total of 46 companies shared Quebec's electricity production, involving no less than 9,710 megawatts of power. The 4 companies that controlled 85 per cent of this power were Hydro-Quebec, Aluminum Company of Canada (Alcan), Shawinigan Water and Power Company and the Gatineau Power Company. At the time, electricity rates also varied considerably throughout Quebec, being extremely high in regions far from Montreal, which hindered potential industrial development in those areas. This report discussed the privatization of Hydro-Quebec and how it could make Quebecers richer. The report discussed the early days of electricity in Quebec and outlined the reasons that led Quebec to nationalize the production and distribution of electricity and to entrust its management to Hydro-Quebec. A summary of the developments undertaken to enable Hydro-Quebec to substantially boost its exports to the United States following liberalization of the American market toward the end of the twentieth century was also provided. A comparison group of companies in the United States involved in the production, transmission and distribution of electricity was also presented in order to analyze Hydro-Quebec's performance from various standpoints. Other topics that were addressed in the report included operational efficiency; use of capital; the experience of the United Kingdom; the rise in electricity rates; a strategy for privatization; the public offering; and protecting Quebec electricity consumers. The role of the Quebec government and of Hydro-Quebec were also examined. Electricity exports and electricity and aluminum smelters were also assessed. The report noted that Hydro-Quebec's annual profit would shrink from $2,882 million to $709 million if it had to pay the market price for the electricity it obtains from Churchill Falls. 23 tabs., 1 fig., 2 appendices

Production method of hydrogen jet plasma process in hydro machinery

International Nuclear Information System (INIS)

Amini, F.

2007-01-01

The purpose of present paper is to the process of plasma formation in hydro machinery when a hydro turbine operates at various conditions and load rejection. By investigation the power, shock pressure , and impact effects of hydro machinery, it is revealed that energy and hydrogen are generated by the plasma process. The investigation on several turbines of various hydro power plants reveals that cold fusion process in hydro machinery generates hydrogen. The hypothesis concerning the participation of alkaline metals in river water and the atomic nuclei of the runner blade material in the formation of hydrogen are considered. It is possible to assume hydrogen, deuterium, helium, and tritium atoms (based on Dr. Mizuno and Dr. Kanarev theories) that are formed, diffuse into cavitation bubbles. The plasma is generated during the collapse of the bubble; thus, the quantity of burnt hydrogen determine the volume of generating hydrogen and the impact force caused by hydrogen explosion (noise).There are five main notions, which can determine hydrogen and plasma process: (1) turbine power effect, (2) high shock pressure, (3) crack on turbine parts, (4) impacts effects and (4) the lift of rotating parts. The frequency of the excitation lies in a range from 0.786 to 1.095 Hz.In future, it may be possible to design hydro turbines based on the plasma process that generates hydrogen; or there may exist turbines that rotate with a mixture of hydrogen explosion and water energies

Rural hydro technology

International Nuclear Information System (INIS)

Fowlie, M.

1999-01-01

This paper examines the increasing use of micro hydroelectric schemes for power generation in mountainous communities in Asia to alleviate some of the pressures on forests. An example of such a scheme in Pakistan is given, and the installation and operation of small hydro units, socio-economic factors, and the impact of the projects on the position of women in the community are discussed. (UK)

Navigating the hydro market in Latin America

International Nuclear Information System (INIS)

Yermoli, C.A.

1995-01-01

The governments of most Latin American countries have yet to establish clear policies about the future ownership of existing generation assets, but they do expect future capacity to be largely developed by the private sector. There were at one time plans for many government-financed hydro projects in the area, but these projects produced much paper and little electricity. Present trends will take the area toward independent power projects, both hydro projects and thermal power projects. This article is a review of those present trends

The Grossmatt hydro-power station

International Nuclear Information System (INIS)

Hintermann, M.

2006-01-01

This final report for the Swiss Federal Office of Energy (SFOE) presents the project for a small hydropower station on the Birs river in north-western Switzerland. The report reviews the history of the project, in which a new 385 kW-hydro-power station at the site of an earlier installation is foreseen. Details are presented on the investigations made and on the co-ordination with the owners of the hydro-power station situated up-river, the local power utility and the local authorities. Also, the requirements placed on the project by the fishing authorities are quoted and the solution foreseen is described. Also discussed are the requirements placed on the project by legislation on environmental impact and flood protection. Figures on electrical energy production and building costs are presented

The changing hydro-ecological dynamics of rivers and deltas of the Western Indian Ocean: Anthropogenic and environmental drivers, local adaptation and policy response

Science.gov (United States)

Duvail, Stéphanie; Hamerlynck, Olivier; Paron, Paolo; Hervé, Dominique; Nyingi, Wanja D.; Leone, Michele

2017-10-01

The rivers flowing into the Western Indian Ocean have steep headwater gradients and carry high sediment loads. In combination with strong tides and seasonal rainfall, these rivers create dynamic deltas with biodiversity-rich and productive ecosystems that, through flooding, have sustained indigenous use systems for centuries. However, river catchments are rapidly changing due to deforestation. Hydropower dams also increasingly alter flood characteristics, reduce sediment supply and contribute to coastal erosion. These impacts are compounded by climate change. Altogether, these changes affect the livelihoods of the delta users. Here, based on prior works that we and others have conducted in the region, we analyse the drivers of these hydro-ecological changes. We then provide recommendations for improved dam design and operations to sustain the underlying delta-building processes, the ecosystem values and the needs of the users.

Comprehensive nonlocal analysis of piezoelectric nanobeams with surface effects in bending, buckling and vibrations under magneto-electro-thermo-mechanical loading

Science.gov (United States)

Ebrahimi-Nejad, Salman; Boreiry, Mahya

2018-03-01

The bending, buckling and vibrational behavior of size-dependent piezoelectric nanobeams under thermo-magneto-mechano-electrical environment are investigated by performing a parametric study, in the presence of surface effects. The Gurtin-Murdoch surface elasticity and Eringen’s nonlocal elasticity theories are applied in the framework of Euler–Bernoulli beam theory to obtain a new non-classical size-dependent beam model for dynamic and static analyses of piezoelectric nanobeams. In order to satisfy the surface equilibrium equations, cubic variation of stress with beam thickness is assumed for the bulk stress component which is neglected in classical beam models. Results are obtained for clamped - simply-supported (C-S) and simply-supported - simply-supported (S-S) boundary conditions using a proposed analytical solution method. Numerical examples are presented to demonstrate the effects of length, surface effects, nonlocal parameter and environmental changes (temperature, magnetic field and external voltage) on deflection, critical buckling load and natural frequency for each boundary condition. Results of this study can serve as benchmarks for the design and analysis of nanostructures of magneto-electro-thermo-elastic materials.

Thai-Myanmar joint hydro schemes

Energy Technology Data Exchange (ETDEWEB)

Boonpiraks, S [Electricity Generating Authority of Thailand, Nonthaburi (Thailand)

1992-10-01

A brief overview is presented here of planned cooperation between Thailand and Myanmar to harness the hydro resources available along the border of the two countries. This would reduce their dependence on thermal generation. (author).

Interaction between daily load demand curve and management of hydro-thermal generation system

International Nuclear Information System (INIS)

Granelli, G.; Montagna, M.; Pasini, G.; Innorta, M.; Marannino, P.

1993-01-01

The influence that the behaviour of the daily load demand curve has on the management of a hydro-thermal generation system is considered. The aim of this paper is to show the improvements that can be achieved by suitable load management techniques capable of flattening the load demand curve. The analysis is carried out by using a hydro-thermal scheduling program and a thermal unit dynamic dispatch procedure. The possibility of properly re-committing the available thermal units is also taken into account. The economical and technical convenience of shutting down less economical thermal units operating near the lower generations limits is verified. Finally, some considerations are made about the possible use of the thermal generation incremental costs as a tool for planning the end users' kWh prices, even in the short term. The results refer to a system with characteristics similar to those of the Italian one. In determining the daily load demand curves, the characteristics of load demand in Italy as well as in other European countries are taken into account

BC Hydro's transmission business : transition to a competitive marketplace

International Nuclear Information System (INIS)

Threlkeld, R.J.

1998-01-01

Progress made by BC Hydro to facilitate the use of the transmission system for wholesale electricity transactions, including the separation of the system operation function from generation and merchant functions, was discussed. BC Hydro, Canada's third largest electric utility, was the first Canadian utility to offer open access to its transmission system for wholesale transactions. The utility has an installed generating capacity of about 10.8 gigawatts, 90 per cent of which is hydroelectric. The remainder is thermal, gas turbine and stationary and mobile diesel generation. The key element in establishing wholesale transmission transactions was the FERC-mandated open access same-time information system (OASIS) on which BC Hydro posts available transmission capacity, planned outages and pricing. The system operates on BC Hydro's internet node and interfaces to a Transmission Scheduling System (TSS). The TSS was developed in-house to handle the increased complexity of scheduling multiple energy and capacity transactions for users of the transmission system. Operation of the system and the challenge to constantly improve it were discussed

Magneto-Optical Thin Films for On-Chip Monolithic Integration of Non-Reciprocal Photonic Devices.

Science.gov (United States)

Bi, Lei; Hu, Juejun; Jiang, Peng; Kim, Hyun Suk; Kim, Dong Hun; Onbasli, Mehmet Cengiz; Dionne, Gerald F; Ross, Caroline A

2013-11-08

Achieving monolithic integration of nonreciprocal photonic devices on semiconductor substrates has been long sought by the photonics research society. One way to achieve this goal is to deposit high quality magneto-optical oxide thin films on a semiconductor substrate. In this paper, we review our recent research activity on magneto-optical oxide thin films toward the goal of monolithic integration of nonreciprocal photonic devices on silicon. We demonstrate high Faraday rotation at telecommunication wavelengths in several novel magnetooptical oxide thin films including Co substituted CeO₂ -δ , Co- or Fe-substituted SrTiO 3- δ , as well as polycrystalline garnets on silicon. Figures of merit of 3~4 deg/dB and 21 deg/dB are achieved in epitaxial Sr(Ti 0.2 Ga 0.4 Fe 0.4 )O 3- δ and polycrystalline (CeY₂)Fe₅O 12 films, respectively. We also demonstrate an optical isolator on silicon, based on a racetrack resonator using polycrystalline (CeY₂)Fe₅O 12 /silicon strip-loaded waveguides. Our work demonstrates that physical vapor deposited magneto-optical oxide thin films on silicon can achieve high Faraday rotation, low optical loss and high magneto-optical figure of merit, therefore enabling novel high-performance non-reciprocal photonic devices monolithically integrated on semiconductor substrates.

The design and development of a high-throughput magneto-mechanostimulation device for cartilage tissue engineering.

Science.gov (United States)

Brady, Mariea A; Vaze, Reva; Amin, Harsh D; Overby, Darryl R; Ethier, C Ross

2014-02-01

To recapitulate the in vivo environment and create neo-organoids that replace lost or damaged tissue requires the engineering of devices, which provide appropriate biophysical cues. To date, bioreactors for cartilage tissue engineering have focused primarily on biomechanical stimulation. There is a significant need for improved devices for articular cartilage tissue engineering capable of simultaneously applying multiple biophysical (electrokinetic and mechanical) stimuli. We have developed a novel high-throughput magneto-mechanostimulation bioreactor, capable of applying static and time-varying magnetic fields, as well as multiple and independently adjustable mechanical loading regimens. The device consists of an array of 18 individual stations, each of which uses contactless magnetic actuation and has an integrated Hall Effect sensing system, enabling the real-time measurements of applied field, force, and construct thickness, and hence, the indirect measurement of construct mechanical properties. Validation tests showed precise measurements of thickness, within 14 μm of gold standard calliper measurements; further, applied force was measured to be within 0.04 N of desired force over a half hour dynamic loading, which was repeatable over a 3-week test period. Finally, construct material properties measured using the bioreactor were not significantly different (p=0.97) from those measured using a standard materials testing machine. We present a new method for articular cartilage-specific bioreactor design, integrating combinatorial magneto-mechanostimulation, which is very attractive from functional and cost viewpoints.

Miksova hydro-electric power plant is awaiting the fortieths

International Nuclear Information System (INIS)

Regula, E.

2004-01-01

In this paper the history of cascade of the Miksova hydro-electric power plants (HEPP, in the Slovak Republic) is described. This cascade of power plants consists of the following hydro-electric power plant: Hricov HEPP, Miksova HEPP, Povazska Bystrica HEPP and Nosice HEPP. In the Miksova HEPP are installed three turbo-sets with Kaplan turbine from the CKD Blansko and with synchronous hydro-alternator. Synchronous hydroelectric alternators have maximal output by 31.2 MW. Their installed output is together 93.6 MW and projected production of electric energy is 207 GWh annually. To the end 2003 Miksova HEPP during 40 years has produced together 7,161,342 MWh of electric energy

Controlling the influence of elastic eigenmodes on nanomagnet dynamics through pattern geometry

Energy Technology Data Exchange (ETDEWEB)

Berk, C., E-mail: crberk@soe.ucsc.edu [School of Engineering, University of California Santa Cruz, 1156 High Street, Santa Cruz, CA 95064 (United States); Yahagi, Y. [School of Engineering, University of California Santa Cruz, 1156 High Street, Santa Cruz, CA 95064 (United States); Dhuey, S.; Cabrini, S. [Molecular Foundry, Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States); Schmidt, H. [School of Engineering, University of California Santa Cruz, 1156 High Street, Santa Cruz, CA 95064 (United States)

2017-03-15

The effect of the nanoscale array geometry on the interaction between optically generated surface acoustic waves (SAWs) and nanomagnet dynamics is investigated using Time-Resolved Magneto-Optical Kerr Effect Microscopy (TR-MOKE). It is demonstrated that altering the nanomagnet geometry from a periodic to a randomized aperiodic pattern effectively removes the magneto-elastic effect of SAWs on the magnetization dynamics. The efficiency of this method depends on the extent of any residual spatial correlations and is quantified by spatial Fourier analysis of the two structures. Randomization allows observation and extraction of intrinsic magnetic parameters such as spin wave frequencies and damping to be resolvable using all-optical methods, enabling the conclusion that the fabrication process does not affect the damping.

Controlling the influence of elastic eigenmodes on nanomagnet dynamics through pattern geometry

Science.gov (United States)

Berk, C.; Yahagi, Y.; Dhuey, S.; Cabrini, S.; Schmidt, H.

2017-03-01

The effect of the nanoscale array geometry on the interaction between optically generated surface acoustic waves (SAWs) and nanomagnet dynamics is investigated using Time-Resolved Magneto-Optical Kerr Effect Microscopy (TR-MOKE). It is demonstrated that altering the nanomagnet geometry from a periodic to a randomized aperiodic pattern effectively removes the magneto-elastic effect of SAWs on the magnetization dynamics. The efficiency of this method depends on the extent of any residual spatial correlations and is quantified by spatial Fourier analysis of the two structures. Randomization allows observation and extraction of intrinsic magnetic parameters such as spin wave frequencies and damping to be resolvable using all-optical methods, enabling the conclusion that the fabrication process does not affect the damping.

Neuro-fuzzy modelling of hydro unit efficiency

International Nuclear Information System (INIS)

Iliev, Atanas; Fushtikj, Vangel

2003-01-01

This paper presents neuro-fuzzy method for modeling of the hydro unit efficiency. The proposed method uses the characteristics of the fuzzy systems as universal function approximates, as well the abilities of the neural networks to adopt the parameters of the membership's functions and rules in the consequent part of the developed fuzzy system. Developed method is practically applied for modeling of the efficiency of unit which will be installed in the hydro power plant Kozjak. Comparison of the performance of the derived neuro-fuzzy method with several classical polynomials models is also performed. (Author)

Optical and magneto-optical characterization of TbFeCo thin films in trilayer structures

International Nuclear Information System (INIS)

McGahan, W.A.; He, P.; Chen, L.; Bonafede, S.; Woollam, J.A.; Sequeda, F.; McDaniel, T.; Do, H.

1991-01-01

A series of TbFeCo films ranging in thickness from 100 to 800 A have been deposited in trilayer structures on silicon wafer substrates, with Si 3 N 4 being employed as the dielectric material. These films have been characterized both optically and magneto-optically by variable angle of incidence spectroscopic ellipsometry, normal angle of incidence reflectometry, and normal angle of incidence Kerr spectroscopy. From these measurements, the optical constants n and k have been determined for the TbFeCo films, as well as the magneto-optical constants Q1 and Q2. Results are presented that demonstrate the lack of dependence of these constants on the thickness of the TbFeCo film, and which can be used for calculating the expected optical and magneto-optical response of any multilayer structure containing similar TbFeCo films

Natural resources: adjusting and innovating - Hydro-Quebec in the global age

International Nuclear Information System (INIS)

Ouellet, D.

1995-01-01

Although it is believed that the information economy is replacing the mass economy, many companies continue to grow on economies based on natural resources. Recent aggressive growth by Hydro-Quebec in the highly competitive market for energy products was singled out as one of the success stories. Among other things, Hydro-Quebec was reported to focus attention on the globalization of electricity products, particularly in Asia, Europe and Africa. The corporation was said to cooperate with other utilities companies such as Ontario Hydro and Power Asia Assets Corporation to diversify its markets abroad. Hydro-Quebec is also marketing new products, developed in its laboratories and by subsidiaries, such as power system simulators and power system planning and management systems, on a global scale

Magneto-transport properties of a random distribution of few-layer graphene patches

International Nuclear Information System (INIS)

Iacovella, Fabrice; Mitioglu, Anatolie; Pierre, Mathieu; Raquet, Bertrand; Goiran, Michel; Plochocka, Paulina; Escoffier, Walter; Trinsoutrot, Pierre; Vergnes, Hugues; Caussat, Brigitte; Conédéra, Véronique

2014-01-01

In this study, we address the electronic properties of conducting films constituted of an array of randomly distributed few layer graphene patches and investigate on their most salient galvanometric features in the moderate and extreme disordered limit. We demonstrate that, in annealed devices, the ambipolar behaviour and the onset of Landau level quantization in high magnetic field constitute robust hallmarks of few-layer graphene films. In the strong disorder limit, however, the magneto-transport properties are best described by a variable-range hopping behaviour. A large negative magneto-conductance is observed at the charge neutrality point, in consistency with localized transport regime

Charge-order driven multiferroic and magneto-dielectric properties of rare earth manganates

International Nuclear Information System (INIS)

Serrao, Claudy Rayan; Sahu, Jyoti Ranjan; Ghosh, Anirban

2010-01-01

Charge-order driven magnetic ferroelectricity is shown to occur in several rare earth manganates of the general formula, Ln 1-x A x MnO 3 (Ln rare earth, A = alkaline earth). Charge-ordered manganates exhibit dielectric constant anomalies around the charge-ordering or the antiferromagnetic transition temperature. Magnetic fields have a marked effect on the dielectric properties of these compounds, indicating the presence of coupling between the magnetic and electrical order parameters. Magneto-dielectric properties are retained in small particles of the manganates. The observation of magneto-ferroelectricity in these manganates is in accordance with theoretical predictions. (author)

Progress in magneto-encephalography; Les progres de la magnetoencephalographie

Energy Technology Data Exchange (ETDEWEB)

Dehaene, St. [CEA Saclay, Institut d' Imagerie Biomedicale - NeuroSpin, Dir. des Sciences du Vivant, 91 - Gif-sur-Yvette (France); Fermon, C. [CEA Saclay, Direction des Sciences de la Matiere, 91 - Gif-sur-Yvette (France)

2008-07-01

Researchers looking for a higher temporal resolution of cognitive functions are turning to magneto-encephalography (MEG) as an extension to MRI. Progress made in MEG imaging, especially in terms of the sensors employed, is opening up a broader range of applications. (authors)

Magneto-thermal conduction and magneto-caloric effect in poly and nano crystalline forms of multiferroic GdCrO3

International Nuclear Information System (INIS)

Uma, S; Philip, J

2014-01-01

Gadolinium chromite, GdCrO 3 , belongs to the family of rare earth chromites, exhibiting multiferroism with coupling between electric polarization and magnetic ordering. It is understood that the interaction between Gd 3+ and Cr 3+ ions is responsible for switchable polarization in this system. Below Néel temperature the spins of Cr 3+ ions interact in anti-parallel through super exchange mechanism, giving rise to antiferromagnetic ordering at around 169 K in poly and nanocrystalline phases of this material. In order to understand the nature of spin–lattice coupling and magnon–phonon interaction in the intermediate temperature range (150–250 K), the magneto-thermal conduction and magneto-caloric effect in poly and nanocrystalline forms of this material are reported. These properties show anomalies around 169 K, which is described as due to spin–phonon coupling. When particle sizes are reduced to nanometer scales, thermal conductivity decreases significantly while specific heat capacity increases. The former is explained as due to reduction in phonon mean free path and phonon scattering from nanoparticle interfaces, while the latter is ascribed to contributions from Einstein oscillators at weakly bound atoms at the interfaces of nanocrystals. (paper)

75 FR 45607 - Application To Export Electric Energy; Manitoba Hydro

Science.gov (United States)

2010-08-03

... DEPARTMENT OF ENERGY [OE Docket No. EA-281-B] Application To Export Electric Energy; Manitoba Hydro AGENCY: Office of Electricity Delivery and Energy Reliability, DOE. ACTION: Notice of application. SUMMARY: Manitoba Hydro (Manitoba) has applied to renew its authority to transmit electric energy from the...

A flexible experimental setup for femtosecond time-resolved broad-band ellipsometry and magneto-optics

Energy Technology Data Exchange (ETDEWEB)

Boschini, F.; Hedayat, H.; Piovera, C.; Dallera, C. [Dipartimento di Fisica, Politecnico di Milano, p.zza Leonardo da Vinci 32, 20133 Milano (Italy); Gupta, A. [Department of Chemistry, University of Alabama, Tuscaloosa, Alabama 35487 (United States); Carpene, E., E-mail: ettore.carpene@polimi.it [CNR-IFN, Dipartimento di Fisica, Politecnico di Milano, p.zza Leonardo da Vinci 32, 20133 Milano (Italy)

2015-01-15

A versatile experimental setup for femtosecond time-resolved ellipsometry and magneto-optical Kerr effect measurements in the visible light range is described. The apparatus is based on the pump-probe technique and combines a broad-band probing beam with an intense near-infrared pump. According to Fresnel scattering matrix formalism, the analysis of the reflected beam at different polarization states of the incident probe light allows one to determine the diagonal and the off-diagonal elements of the dielectric tensor in the investigated sample. Moreover, the pump-probe method permits to study the dynamics of the dielectric response after a short and intense optical excitation. The performance of the experimental apparatus is tested on CrO{sub 2} single crystals as a benchmark.

A flexible experimental setup for femtosecond time-resolved broad-band ellipsometry and magneto-optics

International Nuclear Information System (INIS)

Boschini, F.; Hedayat, H.; Piovera, C.; Dallera, C.; Gupta, A.; Carpene, E.

2015-01-01

A versatile experimental setup for femtosecond time-resolved ellipsometry and magneto-optical Kerr effect measurements in the visible light range is described. The apparatus is based on the pump-probe technique and combines a broad-band probing beam with an intense near-infrared pump. According to Fresnel scattering matrix formalism, the analysis of the reflected beam at different polarization states of the incident probe light allows one to determine the diagonal and the off-diagonal elements of the dielectric tensor in the investigated sample. Moreover, the pump-probe method permits to study the dynamics of the dielectric response after a short and intense optical excitation. The performance of the experimental apparatus is tested on CrO 2 single crystals as a benchmark

On-line irradiation testing of a Giant Magneto-Resistive (GMR) sensor

Energy Technology Data Exchange (ETDEWEB)

Olfert, J.; Luloff, B.; MacDonald, D.; Lumsden, R., E-mail: jeff.olfert@cnl.ca [Canadian Nuclear Laboratories, Chalk River, Ontario (Canada)

2016-06-15

Magneto-resistive sensors are rapidly gaining favour for magnetic field sensing applications owing to their high sensitivity, small size, and low cost. Their metallic, nonsemiconductor construction makes them excellent candidates for use in the harsh environments present in nuclear and space applications. In this work, a commercially available magneto-resistive sensor was irradiated up to a total gamma dose of 2 MGy (200 Mrad), and online testing was performed to monitor the sensor throughout the irradiation to detect any degradation. No significant evidence of degradation of the sensor characteristics was observed. A very small (< 1%) change in the bridge balance of the sensor as a function of accumulated dose was detected. (author)

Circular heat and momentum flux radiated by magneto-optical nanoparticles

Science.gov (United States)

Ott, A.; Ben-Abdallah, P.; Biehs, S.-A.

2018-05-01

In the present article we investigate the heat and momentum fluxes radiated by a hot magneto-optical nanoparticle in its surroundings under the action of an external magnetic field. We show that the flux lines circulate in a confined region at a nanometric distance from the particle around the axis of the magnetic field in a vortexlike configuration. Moreover we prove that the spatial orientation of these vortices (clockwise or counterclockwise) is associated with the contribution of optical resonances with topological charges m =+1 or m =-1 to the thermal emission. This work paves the way for a geometric description of heat and momentum transport in lattices of magneto-optical particles. Moreover it could have important applications in the field of energy storage as well as in thermal management at nanoscale.

The hydro-mechanical modeling of the fractured media

International Nuclear Information System (INIS)

Kadiri, I.

2002-10-01

The hydro-mechanical modeling of the fractured media is quite complex. Simplifications are necessary for the modeling of such media, but, not always justified, Only permeable fractures are often considered. The rest of the network is approximated by an equivalent continuous medium. Even if we suppose that this approach is validated, the hydraulic and mechanical properties of the fractures and of the continuous medium are seldom known. Calibrations are necessary for the determination of these properties. Until now, one does not know very well the nature of measurements which must be carried out in order to carry on a modeling in discontinuous medium, nor elements of enough robust validation for this kind of modeling. For a better understanding of the hydro-mechanical phenomena in fractured media, two different sites have been selected for the work. The first is the site of Grimsel in Switzerland in which an underground laboratory is located at approximately 400 m of depth. The FEBEX experiment aims at the in-situ study of the consecutive phenomena due to the installation of a heat source representative of radioactive waste in the last 17 meters of the FEBEX tunnel in the laboratory of Grimsel. Only, the modeling of the hydro-mechanical of the excavation was model. The modeling of the Febex enabled us to establish a methodology of calibration of the hydraulic properties in the discontinuous media. However, this kind of study on such complex sites does not make possible to answer all the questions which arise on the hydro-mechanical behavior of the fractured media. We thus carried out modeling on an other site, smaller than the fist one and more accessible. The experimental site of Coaraze, in the Maritime Alps, is mainly constituted of limestone and fractures. Then the variation of water pressure along fractures is governed by the opening/closure sequence of a water gate. Normal displacement as well as the pore pressure along these fractures are recorded, and then

Dynamic viscous behavior of magneto-rheological fluid in coupled mode operation

International Nuclear Information System (INIS)

Kaluvan, Suresh; Park, JinHyuk; Choi, Seung-Hyun; Kim, Pyunghwa; Choi, Seung-Bok

2015-01-01

A new method of measuring the coupled mode viscosity behavior of magneto-rheological (MR) fluid using the resonance concept is proposed. The coupled mode viscosity measurement device is designed as a resonant system using a cantilever beam probing with the rotating shaft mechanism. The ‘C’ shaped iron core of an electromagnetic coil, mounted in a resonating cantilever beam is used as a probing tip. The MR fluid between the probing tip and the rotating shaft mechanism experiences both squeeze and shear force. The vibration induced by the resonating cantilever beam creates only squeeze force on the MR fluid when the shaft is stationary. When the cantilever beam is vibrating at resonance and the shaft is rotating, the MR fluid experiences coupled (shear and squeeze) force. The cantilever beam is vibrated at its resonant frequency using the piezoelectric actuation technique and the resonance is maintained using simple closed loop resonator electronics. The input current to the probing coil is varied to produce a variable magnetic field which causes the viscosity change of the MR fluid. The viscosity change of the MR fluid produces a coupled force, which induces an additional stiffness on the resonating cantilever beam and alters its initial resonant frequency. The shift in resonant frequency due to the change in viscosity of the MR fluid is measured with the help of a resonator electronics circuit and its viscosity is related to the field dependent coupled mode yield stress of the MR fluid. The proposed measurement device is analytically derived and experimentally evaluated. (technical note)

Response of multiphase magneto-electro-elastic sensors under ...

African Journals Online (AJOL)

The finite element formulation for coupled magneto-electro-elastic sensor bonded to a mild steel beam with plane stress assumption is presented in this paper. The beam is subjected to harmonic excitation with a point load at tip and a uniformly distributed load along the bottom surface of the mild steel beam. Numerical ...

Hydro-Quebec line crew returns home from Haiti

Energy Technology Data Exchange (ETDEWEB)

Horne, D.

2005-04-01

This article recounted the experience of a 14-member Hydro-Quebec line crew and support group that travelled to Haiti in November 2004 to help re-establish essential electricity services. The work was conducted together with Electricite d'Haiti (EDH). The team installed 400 poles, 10 km of conductors and 85 transformers, restoring service to water pumps; La Providence and Raboteau hospitals; a centre housing Doctors without borders; a CARE distribution centre; and several convents and schools. The installation of street lights at strategic points allowed lighting to be restored in several districts of Gonaives. Hydro-Quebec was able to extend their mission to Haiti and purchase more poles and transformers with the help of a $500,000 contribution from the Canadian International Development Agency. Hydro-Quebec was the only company who came to the aid of EDH. The total budget for the project was $4 million. 2 figs.

Bifurcations and chaos of a vibration isolation system with magneto-rheological damper

Energy Technology Data Exchange (ETDEWEB)

Zhang, Hailong [Magneto-electronics Lab, School of Physics and Technology, Nanjing Normal University, Nanjing 210046 (China); Vibration Control Lab, School of Electrical and Automation Engineering, Nanjing Normal University, Nanjing 210042 (China); Zhang, Ning [Magneto-electronics Lab, School of Physics and Technology, Nanjing Normal University, Nanjing 210046 (China); Min, Fuhong; Yan, Wei; Wang, Enrong, E-mail: erwang@njnu.edu.cn [Vibration Control Lab, School of Electrical and Automation Engineering, Nanjing Normal University, Nanjing 210042 (China)

2016-03-15

Magneto-rheological (MR) damper possesses inherent hysteretic characteristics. We investigate the resulting nonlinear behaviors of a two degree-of-freedom (2-DoF) MR vibration isolation system under harmonic external excitation. A MR damper is identified by employing the modified Bouc-wen hysteresis model. By numerical simulation, we characterize the nonlinear dynamic evolution of period-doubling, saddle node bifurcating and inverse period-doubling using bifurcation diagrams of variations in frequency with a fixed amplitude of the harmonic excitation. The strength of chaos is determined by the Lyapunov exponent (LE) spectrum. Semi-physical experiment on the 2-DoF MR vibration isolation system is proposed. We trace the time history and phase trajectory under certain values of frequency of the harmonic excitation to verify the nonlinear dynamical evolution of period-doubling bifurcations to chaos. The largest LEs computed with the experimental data are also presented, confirming the chaotic motion in the experiment. We validate the chaotic motion caused by the hysteresis of the MR damper, and show the transitions between distinct regimes of stable motion and chaotic motion of the 2-DoF MR vibration isolation system for variations in frequency of external excitation.

Bifurcations and chaos of a vibration isolation system with magneto-rheological damper

Directory of Open Access Journals (Sweden)

Hailong Zhang

2016-03-01

Full Text Available Magneto-rheological (MR damper possesses inherent hysteretic characteristics. We investigate the resulting nonlinear behaviors of a two degree-of-freedom (2-DoF MR vibration isolation system under harmonic external excitation. A MR damper is identified by employing the modified Bouc-wen hysteresis model. By numerical simulation, we characterize the nonlinear dynamic evolution of period-doubling, saddle node bifurcating and inverse period-doubling using bifurcation diagrams of variations in frequency with a fixed amplitude of the harmonic excitation. The strength of chaos is determined by the Lyapunov exponent (LE spectrum. Semi-physical experiment on the 2-DoF MR vibration isolation system is proposed. We trace the time history and phase trajectory under certain values of frequency of the harmonic excitation to verify the nonlinear dynamical evolution of period-doubling bifurcations to chaos. The largest LEs computed with the experimental data are also presented, confirming the chaotic motion in the experiment. We validate the chaotic motion caused by the hysteresis of the MR damper, and show the transitions between distinct regimes of stable motion and chaotic motion of the 2-DoF MR vibration isolation system for variations in frequency of external excitation.

Application of reliability methods in Ontario Hydro

International Nuclear Information System (INIS)

Jeppesen, R.; Ravishankar, T.J.

1985-01-01

Ontario Hydro have established a reliability program in support of its substantial nuclear program. Application of the reliability program to achieve both production and safety goals is described. The value of such a reliability program is evident in the record of Ontario Hydro's operating nuclear stations. The factors which have contributed to the success of the reliability program are identified as line management's commitment to reliability; selective and judicious application of reliability methods; establishing performance goals and monitoring the in-service performance; and collection, distribution, review and utilization of performance information to facilitate cost-effective achievement of goals and improvements. (orig.)

Hydro-Quebec International : taking up the challenges of globalization

Energy Technology Data Exchange (ETDEWEB)

Carpentier, J.M.

1997-12-31

With the ever increasing demand for electricity, it is estimated that the world`s electrical generating capacity will grow by about 1,000,000 MW over the next eight years. This represents a 40 per cent increase over today`s capacity. Hydro-Quebec is determined to stake its place in international markets and to maximize the profits from the strong expertise gained during the construction of Quebec`s major electric facilities. The venture into international markets is primarily a commercial strategy. To that effect, Hydro-Quebec plans to invest up to $300 million in international projects around the world so that after five years it can have major interests and assets totaling $12 billion or more. China, North Africa and the Middle East are some of the market that Hydro-Quebec wishes to enter in the years ahead. The Eastern European and Southeast Asian markets are also worthy of interest. It was pointed out that Hydro-Quebec is not the only large electric utility turning to world market to pursue its growth. French, Spanish and American companies are also presently investing billions of dollars in the world market.

Hydro-Quebec International : taking up the challenges of globalization

International Nuclear Information System (INIS)

Carpentier, J.M.

1997-01-01

With the ever increasing demand for electricity, it is estimated that the world''s electrical generating capacity will grow by about 1,000,000 MW over the next eight years. This represents a 40 per cent increase over today''s capacity. Hydro-Quebec is determined to stake its place in international markets and to maximize the profits from the strong expertise gained during the construction of Quebec''s major electric facilities. The venture into international markets is primarily a commercial strategy. To that effect, Hydro-Quebec plans to invest up to $300 million in international projects around the world so that after five years it can have major interests and assets totaling $12 billion or more. China, North Africa and the Middle East are some of the market that Hydro-Quebec wishes to enter in the years ahead. The Eastern European and Southeast Asian markets are also worthy of interest. It was pointed out that Hydro-Quebec is not the only large electric utility turning to world market to pursue its growth. French, Spanish and American companies are also presently investing billions of dollars in the world market

HydroCoils, occlusion rates, and outcomes: a large single-center study.

LENUS (Irish Health Repository)

O'Hare, A M

2010-11-01

The HydroCoil is an expansile hydrogel coil designed to produce a greater degree of volumetric packing within cerebral aneurysms when compared with bare platinum coils. This increased packing is, in turn, believed to decrease the risk of recurrence within aneurysms and hence the risk of their rupture in the long term. The aim of this work was to assess whether the use of HydroCoils and the proportion of HydroCoil used have any influence on the subsequent occlusion and recurrence rates of treated aneurysms.

Role of model structure on the response of soil biogeochemistry to hydro-climatic fluctuations

Science.gov (United States)

Manzoni, S.; Porporato, A.

2005-05-01

Soil carbon and nutrient cycles are strongly affected by hydro-climatic variability, which interacts with the internal ecosystem structure. Here we test the implications of biogeochemical model structure on such dynamics by extending an existing model by the authors and coworkers. When forced by hydro-climatic fluctuations, the different model structures induce specific preferential nutrient paths among the soil pools, which in turn affect nutrient distribution and availability to microbes and plants. In particular, if it is assumed that microbes can directly assimilate organic nitrogen, plants tend to be inferior competitors for nutrients even in well-watered conditions, while if a certain amount of organic nitrogen is assumed to be mineralized without being first incorporated into microbial cells, vegetation can be advantaged over a wide range of soil moisture values. We also investigate the intensification of competition for nutrients (e.g., nitrogen) between plant and soil microbial communities under extreme hydrologic conditions, such as droughts and intense storms. Frequent rainfall events may determine ideal soil moisture conditions for plant uptake, enhancing nitrogen leaching while lowering oxygen concentration and inhibiting microbial activity. During droughts, the soil water potential often drops to the point of hampering the plant nutrient uptake while still remaining high enough for microbial decomposition and nitrogen immobilization. The interplay of microbe and vegetation water stress is investigated in depth as it controls the ability of one community (e.g., plants or soil microbes) to establish competitive advantage on the other. The long-term effects of these dynamics of competition and nutrient allocation are explored under steady-state and stochastic soil moisture conditions to analyze the feedbacks between soil organic matter and vegetation dynamics.

Magneto-Optical Thin Films for On-Chip Monolithic Integration of Non-Reciprocal Photonic Devices

Directory of Open Access Journals (Sweden)

Mehmet Cengiz Onbasli

2013-11-01

Full Text Available Achieving monolithic integration of nonreciprocal photonic devices on semiconductor substrates has been long sought by the photonics research society. One way to achieve this goal is to deposit high quality magneto-optical oxide thin films on a semiconductor substrate. In this paper, we review our recent research activity on magneto-optical oxide thin films toward the goal of monolithic integration of nonreciprocal photonic devices on silicon. We demonstrate high Faraday rotation at telecommunication wavelengths in several novel magnetooptical oxide thin films including Co substituted CeO2−δ, Co- or Fe-substituted SrTiO3−δ, as well as polycrystalline garnets on silicon. Figures of merit of 3~4 deg/dB and 21 deg/dB are achieved in epitaxial Sr(Ti0.2Ga0.4Fe0.4O3−δ and polycrystalline (CeY2Fe5O12 films, respectively. We also demonstrate an optical isolator on silicon, based on a racetrack resonator using polycrystalline (CeY2Fe5O12/silicon strip-loaded waveguides. Our work demonstrates that physical vapor deposited magneto-optical oxide thin films on silicon can achieve high Faraday rotation, low optical loss and high magneto-optical figure of merit, therefore enabling novel high-performance non-reciprocal photonic devices monolithically integrated on semiconductor substrates.

Transformation magneto-statics and illusions for magnets

Science.gov (United States)

Sun, Fei; He, Sailing

2014-10-01

Based on the form-invariant of Maxwell's equations under coordinate transformations, we extend the theory of transformation optics to transformation magneto-statics, which can design magnets through coordinate transformations. Some novel DC magnetic field illusions created by magnets (e.g. rescaling magnets, cancelling magnets and overlapping magnets) are designed and verified by numerical simulations. Our research will open a new door to designing magnets and controlling DC magnetic fields.

Hybrid Micro-Hydro Power Generation Development in Endau Rompin National Park Johor, Malaysia

Directory of Open Access Journals (Sweden)

Yusop Azli

2017-01-01

Full Text Available Micro-Hydro electrical power systems are very useful for remote area electrification which does not had supply from the national grid. On the contrary, this area has river streams with high potential for micro-hydro power generation. As such, the UTHM ECO-Hydro Team embarked on a project for erecting a micro-hydro power plant with collaboration with National Education Research Center (NERC, Johor National Park Corporation in Endau Rompin. The existing power generation in this area at present is by using diesel generator gives negative impact on finance and environment in the long run. It supplies power to several including library, offices, open laboratory, chalets and dorms.. At the moment, the micro-hydro system complements the diesel generator, thus becoming a hybrid power generation system.

Ab-initio study of the magneto-optical properties of the ultrathin films of Fe{sub n}/Au(001)

Energy Technology Data Exchange (ETDEWEB)

Boukelkoul, Mebarek, E-mail: boukelkoul_mebarek@yahoo.fr [Laboratoire de Physique Quantique et Systèmes Dynamiques, Faculté des sciences, Université Sétif1, Sétif, 19000 Algeria (Algeria); Haroun, Mohamed Fahim [Laboratoire de Physique Quantique et Systèmes Dynamiques, Faculté des sciences, Université Sétif1, Sétif, 19000 Algeria (Algeria); Haroun, Abdelhalim [Laboratoire de Physique Quantique et Systèmes Dynamiques, Faculté des sciences, Université Sétif1, Sétif, 19000 Algeria (Algeria); IPCMS, UMR 7504 CNRS-UNISTRA, 23 Rue du Loess, Strasbourg, 67034 France (France)

2016-12-15

With the aim of understand the microscopic origin of the magneto-optical response in the Fe ultrathin films, we used the first principle full-relativistic Spin-Polarized Relativistic Linear Muffin-Tin Orbitals with Atomic Sphere Approximation. We performed an ab-initio study of the structural, magnetic and magneto-optical properties of Fe deposited on semi-infinite Au(001). The structure and growth of the film leads to a pseudomorphic body centered tetragonal structure with tetragonality ratio c/a=1.62, and the pseudomorphic growth is found to be larger than 3 monolayers. The magnetic study revealed a ferromagnetic phase with a large magnetic moment compared to the bulk one. The magneto-optical response is calculated via the polar magneto-optical Kerr effect over a photon energy range up to 10 eV. The most important features of the Kerr rotation spectra are interpreted trough the interband transitions between localized states.

Pico hydro turbines for electricity in rural areas

OpenAIRE

Descotte, Gérard

2016-01-01

This article discusses the feedback and lessons learned, particularly from a survey carried out following the deployment program of a pico hydro power solution in a very isolated rural area in north Laos. This project is part of the strategic development for the rural electrification of Laos, in which pico hydro power facilities constitute the main avenue of progress for the electrification of isolated villages.

Small hydro plant- present scenario and future prospects

International Nuclear Information System (INIS)

Purohit, D.P.

1996-01-01

The article, deals with the methodology of power generation by small hydro power resources, especially in the Himalayan and sub Himalayan regions and the benefits it will bestow to the inhabitants of this region. The development of small hydro power projects in the Himalayas and sub Himalayas would serve as a model for environment- friendly sources of energy to benefit small communities world wide. The use of water turbine generators for the generation of cheaper power is also discussed. 4 refs

A novel magneto-optical crystal Yb:TbVO4

Science.gov (United States)

Zhu, Xianchao; Tu, Heng; Hu, Zhanggui

2018-04-01

Highly transparent Yb:TbVO4 single crystal with dimensions of Ø27 × 41 mm3 alomost without scattering defects has been successfully grown by Czochralski technique. The spectra, thermal properties and laser-induced damage threshold were investigated in detailed. The Faraday rotation (FR) measurement was carried out by means of extinction method. The Verdet constant comes up to 80 rad m-1 T-1 at 1064 nm, significantly larger than TbVO4 (58 rad m-1 T-1) and TGG (40 rad m-1 T-1) reported. Meanwhile, the as-grown crystal presents lower absorption coefficient and higher magneto-optical figure of merit at measured wavelength in comparison with TGG. Moreover, the crystal exhibits a substantially improved extinction ratio (42 dB) in contrast with TbVO4 (29 dB), and exceeds the highest value of TGG (40 dB). These advantages make Yb:TbVO4 a highly promising magneto-optical material candidate for optical isolators in the visible-near infrared region.

Magneto-plasmonic study of aligned Ni, Co and Ni/Co multilayer in polydimethylsiloxane as magnetic field sensor

Energy Technology Data Exchange (ETDEWEB)

Hamidi, Seyedeh Mehri, E-mail: M_hamidi@sbu.ac.ir [Magneto-plasmonic Lab, Laser and Plasma Research Institute, Shahid Beheshti University, Tehran (Iran, Islamic Republic of); Mosaeii, Babak; Afsharnia, Mina [Magneto-plasmonic Lab, Laser and Plasma Research Institute, Shahid Beheshti University, Tehran (Iran, Islamic Republic of); Aftabi, Ali [Physics Department, Shahid Beheshti University, Tehran (Iran, Islamic Republic of); Najafi, Mojgan [Department of Materials Engineering, Hamedan University of Technology, Hamedan (Iran, Islamic Republic of)

2016-11-01

We report the magneto-optical properties of aligned cobalt, Nickel and nickel/ Cobalt multilayer nanowires embedded in polydimethylsiloxane matrix. The NWs prepared by electrodeposition method in anodic alumina template and then dispersed in ethanol and placed in a heater to evaporate the ethanol and finally dispersed in polydimethylsiloxane matrix to reach to the composite. The used external magnetic field arranges the nanowires and our aligned nanowires were investigated by magneto-optical surface plasmon resonance techniques in two easy and hard axis configurations. Our results show the sufficient sensitivity in magneto-optical surface plasmon resonance of Nickel and cobalt arrays nanowires and because the different modulation mechanism in Ni and Co nanodisks, in Ni/Co multilayer we see the magnetization modulation of the excitation angle in accordance with magnetic field modulation of the SPP wave vector in each nanodisk. Finally, we show that the Ni/Co multilayer aligned nanowires can be used as efficient magnetic field sensor. - Highlights: • The magneto-optical properties of aligned multilayer nanowires has been investigated. • We see the sufficient sensitivity in magneto-optical surface plasmon resonance of Ni and Co nanowires. • The magnetic modulation mechanism in Ni/Co multilayer has been changed by angular modulation. • The magnetization modulation of the excitation angle accompanying the SPP wave vector modulation takes place in each nanodisk of multilayer.

The Nothuesli small hydro project

International Nuclear Information System (INIS)

Balachandran, S.; Jorde, K.

2008-01-01

This report for the Swiss Federal Office of Energy (SFOE) discusses the project for a small 16-kilowatt hydro plant on the Gonzenbaechli stream in eastern Switzerland. The site, which was used even before 1860 for obtaining power from the stream is briefly described, as are the present remains of earlier installations. An old Francis turbine has been retrieved and could possibly be reused. Water-flow figures and fall-heights are noted. Design flows and residual water quantities required by legislation are noted and discussed, as are the geology and topology of the catchment area. The proposals for a new hydro-power plant are described, including the apparatus proposed with a power of 20 kVA. Environmental aspects are also discussed, as are the investment costs and the economic viability of the project. The paper is completed with a comprehensive appendix, including detailed cost estimates.

Impact on the aquatic environment of hydro-peaking in hydroelectric plants

International Nuclear Information System (INIS)

Sabaton, C.; Lauters, F.; Valentin, S.

1996-01-01

There are a number of types of hydroelectric installations on French rivers. Some of these intermittently turbine water stored in dammed reservoirs, in order to use available reserves at the most opportune moment for power generation. These plants, run under 'hydro-peaking' management procedures, cause variations in discharge in river sections downstream of the restitution, on a daily or weekly scale. To answer questions concerning the impact of such variations in discharge on the aquatic environment, EDF launched a research program aimed at describing and better understanding the physical and biological phenomena related to hydro-peaking and assessing the possible impact of this type of plant management on French streams. Seven sites subjects to hydro-peaking were studied on rivers with mean flow rates lower than 20 m 3 /s (which corresponds to over 65 % of EDF hydro-peaking sites). Four themes in particular were examined: hydraulic characterization of hydro-peaking, modifications in thermal regime and water quality, response of benthic invertebrates and response of fish populations to hydro-peaking. For fish as well as for invertebrates, the role of the base discharge - in the absence of peaking flow - and that of the morphology of the river bed (and, in particular, the presence of shelter for fish) during periods of strong discharge were clearly highlighted. Impact assessment requires a precise diagnosis of the state of biocenoses. To carry out such a diagnosis, one must reason in terms of species, life phase (particularly the most sensitive phases) and population structure as well as the type of stream and the faunizone involved. A risk assessment is possible by means of simultaneous study of the morphology of the river bed and the response of the signal generated by hydro-peaking in terms of hydrology and physical characteristics downstream of the restitution. (authors)

Magneto-optical and transport studies of ZnO-based dilute magnetic semiconductors

Energy Technology Data Exchange (ETDEWEB)

Behan, A.J. [Department of Physics and Astronomy, University of Sheffield, Sheffield S3 7RH (United Kingdom); Neal, J.R. [Department of Physics and Astronomy, University of Sheffield, Sheffield S3 7RH (United Kingdom)]. E-mail: J.R.Neal@Sheffield.ac.uk; Ibrahim, R.M. [Department of Physics and Astronomy, University of Sheffield, Sheffield S3 7RH (United Kingdom); Mokhtari, A. [Department of Physics and Astronomy, University of Sheffield, Sheffield S3 7RH (United Kingdom); Ziese, M. [Universitaet Leipzig, Fakultaet fuer Physik und Geowissenschaften, Abteilung Supra leitung und Magnetismus, Linnestrasse 5, 04103 Leipzig (Germany); Blythe, H.J. [Department of Physics and Astronomy, University of Sheffield, Sheffield S3 7RH (United Kingdom); Fox, A.M. [Department of Physics and Astronomy, University of Sheffield, Sheffield S3 7RH (United Kingdom); Gehring, G.A. [Department of Physics and Astronomy, University of Sheffield, Sheffield S3 7RH (United Kingdom)

2007-03-15

Thin film samples of ZnO doped with V were grown on sapphire substrates by pulsed laser deposition (PLD). The magnetization was measured by SQUID magnetometry and the films were found to be ferromagnetic at room temperature. The transmission, Faraday rotation and magnetic circular dichroism were measured as a function of frequency at room temperature over an energy range of 1.5-4.0 eV and carrier concentrations were determined from Hall effect measurements. Clear magneto-optical signals that are ferromagnetic in origin were observed at the ZnO band edge and the optimal conditions for observing large ferromagnetic magneto-optic signals are discussed.

Magneto-optical and magnetic properties in a Co/Pd multilayered thin film

Energy Technology Data Exchange (ETDEWEB)

Nwokoye, Chidubem A. [Institute for Magnetics Research, Department of Electrical and Computer Engineering, The George Washington University, DC 20052 (United States); Naval Air Systems Command, Avionics, Sensors and E*Warfare Department, Patuxent River, MD 20670 (United States); Bennett, Lawrence H., E-mail: lbennett@gwu.edu [Institute for Magnetics Research, Department of Electrical and Computer Engineering, The George Washington University, DC 20052 (United States); Della Torre, Edward, E-mail: edt@gwu.edu [Institute for Magnetics Research, Department of Electrical and Computer Engineering, The George Washington University, DC 20052 (United States); Ghahremani, Mohammadreza [Institute for Magnetics Research, Department of Electrical and Computer Engineering, The George Washington University, DC 20052 (United States); Narducci, Frank A. [Naval Air Systems Command, Avionics, Sensors and E*Warfare Department, Patuxent River, MD 20670 (United States)

2017-01-01

The paper describes investigation of ferromagnetism at low temperatures. We explored the magneto-optical properties, influenced by photon–magnon interactions, of a ferromagnetic Co/Pd multilayered thin film below and above the magnon Bose–Einstein Condensation (BEC) temperature. Analyses of SQUID and MOKE low temperature experimental results reveal a noticeable phase transition in both magnetic and magneto-optical properties of the material at the BEC temperature. - Highlights: • The results show the effect of a non-zero chemical potential on the magnetization. • The MOKE and SQUID results show a phase transition point at the same temperature. • Magnon BEC is a major influence of the observed phase transition temperature.

Hydro adventurers

International Nuclear Information System (INIS)

Wood, Janet

2000-01-01

Some of the changes brought about by privatisation of the hydroelectric power industry in Ecuador are discussed. At present, about 25% of the population has no electricity supply; in the remaining areas demand is increasing. Seven new facilities are presently under discussion and these are described briefly. A plant at Abitugua is to be developed as a 'merchant plant' and the meaning and implications of this are described in detail. The present financing programme for Abituaga and an alternative financing programme are detailed. By 2010, some 40% of Ecuador's electricity is expected to come from hydro

Pulsed fusion space propulsion : Computational Magneto-Hydro Dynamics of a multi-coil parabolic reaction chamber

NARCIS (Netherlands)

Romanelli, G; Mignone, Andrea; Cervone, A.

2017-01-01

Pulsed fusion propulsion might finally revolutionise manned space exploration by providing an affordable and relatively fast access to interplanetary destinations. However, such systems are still in an early development phase and one of the key areas requiring further investigations is the

The effect of inhomogeneous initial stress on Love wave propagation in layered magneto-electro-elastic structures

International Nuclear Information System (INIS)

Zhang, J; Shen, Y P; Du, J K

2008-01-01

The effect of inhomogeneous initial stress on Love wave propagation in layered magneto-electro-elastic structures is investigated in this paper. The coupled magneto-electro-elastic field equations are solved by adopting the Wentzel–Kramers–Brillouin (WKB) approximate approach. Then the phase velocity can be calculated by applying boundary and continuity conditions. A specific example of a structure consisting of a CoFe 2 O 4 layer and a BaTiO 3 substrate is used to illustrate the influence of inhomogeneous initial stress on the phase velocity, corresponding coupled magneto-electric factor and stress fields. The different influence between constant initial stress and inhomogeneous initial stress is discussed and the results are expected to be helpful for the preparation and application of Love wave sensors

Report of the special prosecutor: BC Hydro 'Raiwind' project

International Nuclear Information System (INIS)

Fraser, P. D. K.

1999-10-01

A special prosecutor has been appointed by the British Columbia Government to assist the Royal Canadian Mounted Police (RCMP) in its investigation, and to render appropriate charging decisions in the matter of the circumstances surrounding the creation of IPC International Power Corporation (IPC) owned by a Mr. John N. Laxton, former Chairman of BC Hydro and his two children, and its joint venture with BC Hydro for the development of an international power project in Pakistan known as the Raiwind project. Of particular concerns were the conflict of interest breached by Mr. Laxton in loaning a substantial sum of money to a principal member of the Pakistani side of the joint venture, and by the former President and CEO of BC Hydro, Mr. John Sheehan, by his purchase of shares of IPC by a company owned by members of his family. In 1996 Mr. Sheehan's employment as President and CEO was terminated by BC Hydro for breaching internal conflict of interest guidelines and for failing to get approval from BC Hydro for the acquisition of IPC shares. Subsequently, Mr. Sheehan commenced an action against BC Hydro for wrongful dismissal, a claim which was upheld by the Supreme Court of British Columbia. The focus of the special prosecutor's criminal investigation ultimately became the conduct of Mr. Laxton and whether a charge could or should be laid under Section 122 of the Criminal Code. The outcome of his investigation, which is discussed in this report, was that there was no substantial likelihood of conviction under the breach or trust provisions of Section 122 with respect to the indirect purchases by Mr. Laxton of shares in IPC. Nor was there any reason to believe that a personal loan made in high-risk circumstances could be a benefit or advantage to the lender. Furthermore, the loan cannot be causally related to any loss or financial harm to BC Hydro. In fact, it could be argued that Mr. Laxton's private decision to make the loan was of real assistance in ensuring that the

Numerical modelling of hydro-morphological processes dominated by fine suspended sediment in a stormwater pond

Science.gov (United States)

Guan, Mingfu; Ahilan, Sangaralingam; Yu, Dapeng; Peng, Yong; Wright, Nigel

2018-01-01

Fine sediment plays crucial and multiple roles in the hydrological, ecological and geomorphological functioning of river systems. This study employs a two-dimensional (2D) numerical model to track the hydro-morphological processes dominated by fine suspended sediment, including the prediction of sediment concentration in flow bodies, and erosion and deposition caused by sediment transport. The model is governed by 2D full shallow water equations with which an advection-diffusion equation for fine sediment is coupled. Bed erosion and sedimentation are updated by a bed deformation model based on local sediment entrainment and settling flux in flow bodies. The model is initially validated with the three laboratory-scale experimental events where suspended load plays a dominant role. Satisfactory simulation results confirm the model's capability in capturing hydro-morphodynamic processes dominated by fine suspended sediment at laboratory-scale. Applications to sedimentation in a stormwater pond are conducted to develop the process-based understanding of fine sediment dynamics over a variety of flow conditions. Urban flows with 5-year, 30-year and 100-year return period and the extreme flood event in 2012 are simulated. The modelled results deliver a step change in understanding fine sediment dynamics in stormwater ponds. The model is capable of quantitatively simulating and qualitatively assessing the performance of a stormwater pond in managing urban water quantity and quality.

Mathematical Model of the One-stage Magneto-optical Sensor Based on Faraday Effect

Science.gov (United States)

Babaev, O. G.; Paranin, V. D.; Sinitsin, L. I.

2018-01-01

The aim of this work is to refine a model of magneto-optical sensors based on Faraday’s longitudinal magneto-optical effect. The tasks of the study include computer modeling and analysis of the transfer characteristic of a single-stage magneto-optical sensor for various polarization of the input beam and non-ideal optical components. The proposed mathematical model and software make it possible to take into account the non-ideal characteristics of film polaroids observed in operation in the near infrared region and at increased temperatures. On the basis of the results of the model analysis it was found that the dependence of normalized transmission T(γ2) has periodic nature. Choosing the angle (γ 2-γ 1) makes it possible to shift the initial operation point and change the sensitivity dT/dγ 2. The influence of the input beam polarization increases with the increase of polaroid parameter deviation from ideal and shows itself as reduction of modulation depth and angular shift of the sensor conversion response.

Iron Oxide and Gold Based Magneto-Plasmonic Nanostructures for Medical Applications: A Review

Directory of Open Access Journals (Sweden)

Thi Thuy Nguyen

2018-03-01

Full Text Available Iron oxide and gold-based magneto-plasmonic nanostructures exhibit remarkable optical and superparamagnetic properties originating from their two different components. As a consequence, they have improved and broadened the application potential of nanomaterials in medicine. They can be used as multifunctional nanoprobes for magneto-plasmonic heating as well as for magnetic and optical imaging. They can also be used for magnetically assisted optical biosensing, to detect extreme traces of targeted bioanalytes. This review introduces the previous work on magneto-plasmonic hetero-nanostructures including: (i their synthesis from simple “one-step” to complex “multi-step” routes, including seed-mediated and non-seed-mediated methods; and (ii the characterization of their multifunctional features, with a special emphasis on the relationships between their synthesis conditions, their structures and their properties. It also focuses on the most important progress made with regard to their use in nanomedicine, keeping in mind the same aim, the correlation between their morphology—namely spherical and non-spherical, core-satellite and core-shell, and the desired applications.

Steady shear characteristic and behavior of magneto-thermo-elasticity of isotropic MR elastomers

International Nuclear Information System (INIS)

Gao, Wei; Wang, Xingzhe

2016-01-01

The magneto-thermo-elastic steady shear behaviors of isotropic smart composites of silicon rubber matrix randomly filled with ferromagnetic particles, commonly referred to as magnetorheological (MR) elastomers, are investigated experimentally and theoretically in the present study. The strip specimens of the MR elastomer composite with different ferromagnetic particle concentrations are fabricated and implemented for lap-shear tests under both magnetic and thermal fields. It is illustrated that the magneto-thermo-elastic shear modulus of the MR elastomer is markedly enhanced with the volume fraction of ferromagnetic particles and the applied external magnetic field, while the shear modulus is decreased with the environment temperature. To qualitatively elucidate the magneto-thermo-elastic shear performance of this kind of magnetic smart composites, a modified constitutive of hyperelasticity is suggested taking into account the influence of magnetic field and temperature on the magnetic potential energy and strain energy. The theoretical modeling predictions on the stress–strain behaviors for different applied magnetic fields and environment temperatures are compared to experimental observations to demonstrate a good agreement. (paper)

Magnetic thaw-down and boil-off due to magneto acceptors in 2DEG

International Nuclear Information System (INIS)

Chaubet, C.; Raymond, A.; Bisotto, I.; Harmand, J. C.; Kubisa, M.; Zawadzki, W.

2013-01-01

The Quantum Hall Effect (QHE) and Shubnikov-de Haas effect are investigated experimentally using n type modulation-doped GaAs/GaAlAs quantum wells (QWs) additionally doped in the well with beryllium acceptor atoms. It is presently shown that the localized magneto-acceptor (MA) states which possess discrete energies above the corresponding Landau levels (LLs) lead to two observable effects in magneto-transport: magnetic thaw-down and magnetic boil-off of 2D electrons. Both effects are related to the fact that electrons occupying the localized MA states cannot conduct. Thus in the thaw-down effect the electrons fall down from the MA states to the free Landau states. This leads to a shift of the Hall plateau towards higher magnetic fields as a consequence of an increase of the 2D electron density N S . In the boil-off effect the electrons are pushed from the free Landau states to the empty MA states under high enough Hall electric field. This process has an avalanche character leading to a dramatic increase of magneto-resistance, consequence of a decrease of N S

Cost-benefit analysis of Hydro-Quebec's energy conservation programs

International Nuclear Information System (INIS)

Arsenault, E.

1993-09-01

A cost-benefit analysis is presented of the energy conservation programs of Hydro-Quebec for 1991 to 2010. Three possible scenarios are simulated. In the first scenario, Hydro-Quebec data are used without modification. In the second, the simulation is carried out in the absence of the Hydro-Quebec programs, and in the third, it is assumed that any economies achieved are only for the short term. A comparison between these simulations allows determination of results concerning the advantages and the costs which the programs introduce for the three groups comprising society: the consumer, the producer, and the government. The results of these comparisons show that the consumer, the producer, and the whole society gain benefits from the energy conservation programs, while the government loses. 13 refs., 13 figs., 14 tabs

Mission: Partnerships - A Socially Responsible Approach for New Hydro-electric Developments

Energy Technology Data Exchange (ETDEWEB)

Wojczynski, Ed; Cole, Victoria; Pachal, Shawna; Goulet, Richard

2010-09-15

Worldwide there is a desire for clean, secure and renewable energy developed in an environmentally and socially responsible manner. In the Canadian province of Manitoba, where water is an abundant resource, efforts are being undertaken by Manitoba Hydro to achieve this goal through the development of new hydro-electric generating stations in partnership with Aboriginal (indigenous) communities. This paper focuses on the lessons learned by Manitoba Hydro in developing and implementing partnership agreements with northern Aboriginal communities on two new generation projects - the Wuskwatim Generation Project and the Keeyask Generation Project.

5. ITER International Summer School - Programme and Abstract book

International Nuclear Information System (INIS)

Van Dam, J.W.; Gorelenkov, N.N.; Pueschel, M.J.; Berk, H.L.; Nazikian, R.; Pustovitov, V.D.; Lin, Z.; Koenis, A.; White, R.B.; Lilley, M.; Kiptily, V.G.; Sharapov, S.E.; Fisch, N.J.; Ganesh, R.; Putvinski, S.; Toi, Kazuo; Guimaraes-Filho, Z.O.; Todo, Y.; Bader, A.; Bonoli, P.; Granetz, R.; Harvey, R.W.; Jaeger, E.F.; Parker, R.; Wukitch, S.; Bass, E.M.; Waltz, R.E.; Bellintani, V.; Ozono, E.M.; Severo, J.H.F.; Kusnetzov, Y.; Galvao, R.M.O.; Botrugno, A.; Buratti, P.; Fusco, V.; Pucella, G.; Zonca, F.; Guimaraes, Z.; Di Troia, C.; Divin, A.; Lapenta, G.; Markidis, S.; Dong, Yunbo; Liu, Y.; Deng, W.; Rao, J.; Zhou, J.; Yang, Q.W.; Huang, Y.; Zhou, Y.; Li, W.; Song, X.M.; Dong, J.Q.; Cao, J.Y.; Garcia-Martinez, P.L.; Firpo, M.C.; Lifchitz, A.F.; Ferrari, H.E.; Farengo, R.; Ghantous, K.; Berk, H.L.; Gorelenkov, N.N.; Haskey, S.R.; Blackwell, B.D.; Hole, M.J.; Pretty, D.G.; Howard, J.; Iatsenko, N.; Iatsenko, E.; James, A.N.; Kappatou, A.; Delabie, E.; Jaspers, R.J.E.; Von Hellermann, M.G.; King, J.D.; La Haye, R.J.; Petty, C.C.; Osborne, T.H.; Lasnier, C.J.; Groebner, R.J.; Volpe, F.; Lanctot, M.J.; Makowski, M.A.; Holcomb, C.T.; Allen, S.L.; Luce, T.C.; Austin, M.E.; Meyer, W.H.; Morse, E.C.; Koliner, J.J.; Forest, C.B.; Sarff, J.S.; Oliva, S.; Anderson, J.K.; Almagri, A.R.; Koskela, T.; Kurki-Suonio, T.; Akaslompolo, S.; Asunta, O.; Hirvijoki, E.; Snicker, A.; Sipila, S.; Kumar, Sachin; Kumar, Sanjay; Sharma, R.P.; Lanctot, M.J.; Reimerdes, H.; Garofalo, A.M.; Chu, M.S.; Hanson, J.M.; Liu, Y.Q.; Navratil, G.A.; Bogatu, I.N.; In, Y.; Jackson, G.L.; La Haye, R.J.; Okayabashi, M.; Park, J.K.; Schaffer, M.J.; Schmitz, O.; Strait, E.J.; Lauret, M.; Monnier, A.; Fuhr, G.; Beyer, P.; Benkadda, S.; Garbet, X.; Muscatello, C.M.; Heidbrink, W.W.; Kolesnichenko, Y.I.; Lutsenko, V.V.; Van Zeeland, M.A.; Yakovenko, Y.V.; Ogawa, K.; Isobe, M.; Toi, K.; Spong, D.A.; Osakabe, M.; Papp, G.; Drevlak, M.; Fulop, T.; Helander, P.; Pokol, G.I.; Paz-Soldan, C.; Bergerson, W.F.; Brookhart, M.I.; Hannum, D.A.; Sarff, J.S.; Hegna, C.C.; Forest, C.B.; Saito, Seiki; Takayama, Arimichi; Ito, Atsushi; Nakamura, Hiroaki; Sears, J.; Parker, R.R.; Bader, A.; Golfinopoulos, T.; Kramer, G.J.; Singh, S.K.; Mattoo, S.K.; Awasthi, L.M.; Singh, R.; Kaw, P.K.; Boukhalfa, S.; Tribeche, M.; Zerguini, T.H.; Sversut Arsioli, B.; Ryter, F.; Tarasov, M.I.; Tarasov, I.K.; Sitnikov, D.A.; Slavnyj, A.S.; Kulaga, A.E.; Pavlichenko, R.O.; Berezhnyj, V.L.; Goncharov, I.G.; Prokopendo, A.V.; Shapoval, A.N.; Konovalov, V.G.; Volkov, E.D.; Lozin, A.V.; Tsybenko, S.A.; Pashnev, V.K.; Olshansky, V.V.; Stepanov, K.N.; Thomas, E.; Hopkins, D.; Betton, F.; Tobias, B.J.; Boom, J.E.; Che, S.; Classen, I.G.J.; Domier, C.W.; Donne, A.J.H.; Kong, X.; Kramer, G.J.; Luhmann, N.C.

2013-01-01

This conference provides an overview of MHD (Magneto Hydro-Dynamics) interacting with energetic particles (EP) with regard to the ITER project. The topics covered include: -) key energetic-particles issues for ITER, -) theory of EP-driven modes and associated transport, -) historical review of kinetic MHD, -) kinetic linear stability of EP-MHD modes, -) turbulent transport of fast particles, -) diagnostics of EP-MHD modes, -) experimental observation of EP-driven modes, -) diagnostics for EP-driven modes, -) the use of fast particle driven modes for MHD spectroscopy, -) modelling of EP-MHD modes, -) MHD modes driven by fast electrons: theory, -) MHD modes driven by fast electrons: experiment, -) nonlinear dynamics of EP-driven modes, and -) hybrid simulations of EP-MHD modes. This document puts together the program of the conference, a few abstracts and some posters

Study on Separation of Structural Isomer with Magneto-Archimedes method

Science.gov (United States)

Kobayashi, T.; Mori, T.; Akiyama, Y.; Mishima, F.; Nishijima, S.

2017-09-01

Organic compounds are refined by separating their structural isomers, however each separation method has some problems. For example, distillation consumes large energy. In order to solve these problems, new separation method is needed. Considering organic compounds are diamagnetic, we focused on magneto-Archimedes method. With this method, particle mixture dispersed in a paramagnetic medium can be separated in a magnetic field due to the difference of the density and magnetic susceptibility of the particles. In this study, we succeeded in separating isomers of phthalic acid as an example of structural isomer using MnCl2 solution as the paramagnetic medium. In order to use magneto-Archimedes method for separating materials for food or medicine, we proposed harmless medium using oxygen and fluorocarbon instead of MnCl2 aqueous solution. As a result, the possibility of separating every structural isomer was shown.

Separation of Flame and Nonflame-retardant Plastics Utilizing Magneto-Archimedes Method

International Nuclear Information System (INIS)

Misawa, Kohei; Kobayashi, Takayuki; Mori, Tatsuya; Akiyama, Yoko; Nishijima, Shigehiro; Mishima, Fumihito

2017-01-01

In physical recycling process, the quality of recycled plastics becomes usually poor in case various kinds of plastic materials are mixed. In order to solve the problem, we tried to separate flame and nonflame-retardant plastics used for toner cartridges as one example of mixed plastics by using magneto-Archimedes method. By using this method, we can control levitation and settlement of the particles in the medium by controlling the density and magnetic susceptibility of the medium and the magnetic field. In this study, we introduced the separation system of plastics by the combination of wet type specific gravity separation and magneto-Archimedes separation. In addition, we examined continuous and massive separation by introducing the system which can separate the plastics continuously in the flowing fluid. (paper)

Magneto-optical imaging of polycrystalline FeTe1-xSex prepared at various conditions

International Nuclear Information System (INIS)

Ding, Q.; Taen, T.; Mohan, S.; Nakajima, Y.; Tamegai, T.

2011-01-01

High-quality FeTe 1-x Se x polycrystals with T c ∼ 14 K were prepared by sintering at different temperatures. Intragranular critical current density of FeTe 1-x Se x polycrystals estimated from M-H curve is 5 x 10 4 A/cm 2 at 5 K under zero field. The observed intragranular J c value was confirmed by the magneto-optical images in the remanent state. The weak-link feature of FeTe 1-x Se x polycrystals is also revealed through magneto-optical imaging. We have prepared high-quality polycrystalline FeTe 1-x Se x by sintering at different temperatures and characterized their structural and magnetic properties with X-ray diffraction, magnetization measurements, and magneto-optical imaging. The intragranular J c was estimated to be 5 x 10 4 A/cm 2 , which is smaller than the single crystal, but still in the range for practical applications.

Free vibration analysis of magneto-electro-thermo-elastic nanobeams resting on a Pasternak foundation

Science.gov (United States)

Jandaghian, A. A.; Rahmani, O.

2016-03-01

In this study, free vibration analysis of magneto-electro-thermo-elastic (METE) nanobeams resting on a Pasternak foundation is investigated based on nonlocal theory and Timoshenko beam theory. Coupling effects between electric, magnetic, mechanical and thermal loading are considered to derive the equations of motion and distribution of electrical potential and magnetic potential along the thickness direction of the METE nanobeam. The governing equations and boundary conditions are obtained using the Hamilton principle and discretized via the differential quadrature method (DQM). Numerical results reveal the effects of the nonlocal parameter, magneto-electro-thermo-mechanical loading, Winkler spring coefficients, Pasternak shear coefficients and height-to-length ratio on the vibration characteristics of METE nanobeams. It is observed that the natural frequency is dependent on the magnetic, electric, temperature, elastic medium, small-scale coefficient, and height-to-length ratio. These results are useful in the mechanical analysis and design of smart nanostructures constructed from magneto-electro-thermo-elastic materials.

Free vibration analysis of magneto-electro-thermo-elastic nanobeams resting on a Pasternak foundation

International Nuclear Information System (INIS)

Jandaghian, A A; Rahmani, O

2016-01-01

In this study, free vibration analysis of magneto-electro-thermo-elastic (METE) nanobeams resting on a Pasternak foundation is investigated based on nonlocal theory and Timoshenko beam theory. Coupling effects between electric, magnetic, mechanical and thermal loading are considered to derive the equations of motion and distribution of electrical potential and magnetic potential along the thickness direction of the METE nanobeam. The governing equations and boundary conditions are obtained using the Hamilton principle and discretized via the differential quadrature method (DQM). Numerical results reveal the effects of the nonlocal parameter, magneto-electro-thermo-mechanical loading, Winkler spring coefficients, Pasternak shear coefficients and height-to-length ratio on the vibration characteristics of METE nanobeams. It is observed that the natural frequency is dependent on the magnetic, electric, temperature, elastic medium, small-scale coefficient, and height-to-length ratio. These results are useful in the mechanical analysis and design of smart nanostructures constructed from magneto-electro-thermo-elastic materials. (paper)

State of the art of control schemes for smart systems featuring magneto-rheological materials

International Nuclear Information System (INIS)

Choi, Seung-Bok; Do, Phu Xuan; Li, Weihua; Yu, Miao; Fu, Jie; Du, Haiping

2016-01-01

This review presents various control strategies for application systems utilizing smart magneto-rheological fluid (MRF) and magneto-rheological elastomers (MRE). It is well known that both MRF and MRE are actively studied and applied to many practical systems such as vehicle dampers. The mandatory requirements for successful applications of MRF and MRE include several factors: advanced material properties, optimal mechanisms, suitable modeling, and appropriate control schemes. Among these requirements, the use of an appropriate control scheme is a crucial factor since it is the final action stage of the application systems to achieve the desired output responses. There are numerous different control strategies which have been applied to many different application systems of MRF and MRE, summarized in this review. In the literature review, advantages and disadvantages of each control scheme are discussed so that potential researchers can develop more effective strategies to achieve higher control performance of many application systems utilizing magneto-rheological materials. (topical review)

The hydro energy; Energie hydraulique

Energy Technology Data Exchange (ETDEWEB)

Vachey, C.

2000-05-01

This paper is a first approach of the hydro energy energy. It presents the principle and the applications of this energy source. It proposes recommendations on the sizing and the cost estimation of an installation and the environmental impacts of this energy. (A.L.B.)

Compression of magnetized target in the magneto-inertial fusion

Science.gov (United States)

Kuzenov, V. V.

2017-12-01

This paper presents a mathematical model, numerical method and results of the computer analysis of the compression process and the energy transfer in the target plasma, used in magneto-inertial fusion. The computer simulation of the compression process of magnetized cylindrical target by high-power laser pulse is presented.

Thermo-hydro-mechanical behaviour of Boom clay; Comportement thermo-hydro-mecanique de l'argile de Boom

Energy Technology Data Exchange (ETDEWEB)

Le, T.T

2008-01-15

This thesis studied the thermo-hydro-mechanical properties of Boom clay, which was chosen to be the host material for the radioactive waste disposal in Mol, Belgium. Firstly, the research was concentrated on the soil water retention properties and the hydro-mechanical coupling by carrying out axial compression tests with suction monitoring. The results obtained permitted elaborating a rational experimental procedure for triaxial tests. Secondly, the systems for high pressure triaxial test at controlled temperature were developed to carry out compression, heating, and shearing tests at different temperatures. The obtained results showed clear visco-elasto-plastic behaviour of the soil. This behaviour was modelled by extending the thermo-elasto-plastic model of Cui et al. (2000) to creep effect. (author)

Design and development of the Macpherson Proton Preve Magneto rheological damper with PID controller

Science.gov (United States)

Amiruddin, I. M.; Pauziah, M.; Aminudin, A.; Unuh, M. H.

2017-10-01

Since the creation of the first petrol-fuelled vehicle by Karl Benz in the late nineteenth century, car industry has grown considerably to meet the industrial demands. Luxurious looks and agreeable rides are the primary needs of drivers. The Magneto-rheological damper balanced their damping trademark progressively by applying the damping coefficient depending on the control system. In this research, the control calculations are assessed by utilizing the MR damper. The capacity and reliably of the target force for the damper speed is investigated from control algorithm. This is imperative to defeat the damper limitation. In this study, the simulation results of the semi-dynamic MR damper with the PID controller shows better performance in sprung mass acceleration, unsprung mass acceleration and suspension dislodging with permitting over the top tyre acceleration. The altered model of the MR damper is specially designed for Proton Preve specifications and semi-active PID control. The procedure for the advancement incorporates the numerical model to graphically recreate and break down the dynamic framework by utilizing Matlab.

Towards A Grid Infrastructure For Hydro-Meteorological Research

Directory of Open Access Journals (Sweden)

Michael Schiffers

2011-01-01

Full Text Available The Distributed Research Infrastructure for Hydro-Meteorological Study (DRIHMS is a coordinatedaction co-funded by the European Commission. DRIHMS analyzes the main issuesthat arise when designing and setting up a pan-European Grid-based e-Infrastructure for researchactivities in the hydrologic and meteorological fields. The main outcome of the projectis represented first by a set of Grid usage patterns to support innovative hydro-meteorologicalresearch activities, and second by the implications that such patterns define for a dedicatedGrid infrastructure and the respective Grid architecture.

New directions in nuclear waste disposal in Ontario Hydro

International Nuclear Information System (INIS)

Nash, K.

1996-01-01

Ontario Hydro Nuclear has financial, environmental, safety and public acceptance business objectives which must be met to achieve long term sustainable success. Short term objectives of achieving nuclear excellence in safety, cost and production are vital to this success. Ontario Hydro's nuclear waste and decommissioning liabilities must be managed within these objectives. This paper outlines the financial environmental and societal considerations and responsibility framework for managing these liabilities. (author)

Shocks in magneto-reactive-gas dynamics with application to the piston problem; Sur les chocs dans un milieu magnetodynamique reactif avec application au probleme du piston

Energy Technology Data Exchange (ETDEWEB)

Soubbaramayer, [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

1967-03-01

This work deals with detonation and deflagration waves in magnetogasdynamics. Four types of detonations and four types of deflagration are considered. We point out that the propagation of these waves is not always completely determined by the initial boundary conditions and the conservation laws across the discontinuity. To fix the ideas we consider the piston problem and we show that in some cases more conditions must be added to the conservation laws in order to provide sufficient data for the unique determination of the propagation process. We then show that the needed additional conditions may be derived from an investigation of the internal structure of the detonation and deflagration process in magneto gas dynamics. This internal structure is investigated for the eight types of process under the influence of the combustion mechanism and the dissipative coefficients (viscosities, electrical and thermal conductivity). Finally all the possible solutions for the piston problem are discussed in a simple case. The methods developed here may be extended to ionizing shocks. (author) [French] On considere dans ce travail les ondes de detonation et de deflagration en magneto-dynamique. Quatre types de detonation et quatre types de deflagration sont etudies. On montre d'abord que la propagation de ces ondes n'est pas toujours completement determinee par les conditions initiales, les conditions aux limites et les conditions de choc. Pour fixer les idees nous considerons le probleme du piston et nous montrons que, dans certains cas, des conditions supplementaires doivent etre jointes aux conditions de choc pour determiner l'ecoulement d'une facon unique. Nous montrons ensuite que ces conditions supplementaires peuvent etre deduites de l'analyse de la structure interne des detonations et des deflagrations magnetodynamiques. Cette structure interne est etudiee en tenant compte du mecanisme de combustion et des coefficients de dissipation (viscosites, conductivites

Proposed Hydro-Quebec development plan, 1993: Proposal

International Nuclear Information System (INIS)

1992-01-01

The Quebec government now requires Hydro-Quebec to submit a development plan every three years instead of annually, in order to permit more in-depth studies and a broader consultation with interested parties. In the first of such three-year plans, a series of plan proposals is presented which was developed after a year of consultation with various groups on four fundamental matters: energy efficiency, means of generation, electro-intensive industries, and electricity exports. Options for meeting future demand at Hydro-Quebec are assessed, including the construction of new generation and transmission facilities, rehabilitation of existing facilities, improving electrical energy efficiency, and conservation strategies. These options are considered while applying the principle of sustainable development that respects the environment. Hydroelectricity will continue to be emphasized as the main source of generation since hydroelectric facilities offer distinct advantages in terms of costs, environmental impacts, and economic spinoffs. The proposed plan also presents objectives and strategies for improving the quality of service and internal operations. Financial forecasts for Hydro-Quebec are proposed which take into account the forecast changes in the utility's cost and revenue factors and its self-financing requirements. 5 figs., 15 tabs

Oscillatory magneto-convection under magnetic field modulation

OpenAIRE

Kiran, Palle; Bhadauria, B.S.; Narasimhulu, Y.

2017-01-01

In this paper we investigate an oscillatory mode of nonlinear magneto-convection under time dependant magnetic field. The time dependant magnetic field consists steady and oscillatory parts. The oscillatory part of the imposed magnetic field is assumed to be of third order. An externally imposed vertical magnetic field in an electrically conducting horizontal fluid layer is considered. The finite amplitude analysis is discussed while perturbing the system. The complex Ginzburg-Landau model is...

Remarks on stability of magneto-elastic shocks

Directory of Open Access Journals (Sweden)

Włodzimierz Domański

2015-12-01

Full Text Available The problem of stability of plane shock waves for a model of perfect magnetoelasticityis investigated. Important mathematical properties, like loss of strict hyperbolicityand loss of genuine nonlinearity, and their consequences for the stability ofmagneto-elastic shocks are discussed. It is shown that some of these shocks do not satisfyclassical Lax stability conditions. Both compressible and incompressible models ofmagneto-elasticity are discussed.[b]Keywords[/b]: perfect magneto-elasticity, shock waves, stability conditions

Cobalt nanoparticles deposited and embedded in AlN: Magnetic, magneto-optical, and morphological properties

International Nuclear Information System (INIS)

Huttel, Y.; Gomez, H.; Clavero, C.; Cebollada, A.; Armelles, G.; Navarro, E.; Ciria, M.; Benito, L.; Arnaudas, J.I.; Kellock, A.J.

2004-01-01

We present a structural, morphological, magnetic, and magneto-optical study of cobalt nanoparticles deposited on 50 A ring AlN/c-sapphire substrates and embedded in an AlN matrix. The dependence of the properties of Co nanoclusters deposited on AlN with growth temperature and amount of deposited Co are studied and discussed. Also we directly compare the properties of as grown and AlN embedded Co nanoclusters and show that the AlN matrix has a strong impact on their magnetic and magneto-optical properties

A simple experimental setup for magneto-dielectric measurements

Energy Technology Data Exchange (ETDEWEB)

Manimuthu, P.; Shanker, N. Praveen; Kumar, K. Saravana; Venkateswaran, C., E-mail: cvunom@hotmail.com

2014-09-01

The increasing demand for the multiferroic materials calls for the need of an experimental setup that will facilitate magneto-dielectric coupling measurements. A connector setup designed makes it possible to measure and analyze the dielectric properties of the material under the influence of a magnetic field. The salient feature of this setup is in its incorporation with the already existing experimental facilities.

A simple experimental setup for magneto-dielectric measurements

International Nuclear Information System (INIS)

Manimuthu, P.; Shanker, N. Praveen; Kumar, K. Saravana; Venkateswaran, C.

2014-01-01

The increasing demand for the multiferroic materials calls for the need of an experimental setup that will facilitate magneto-dielectric coupling measurements. A connector setup designed makes it possible to measure and analyze the dielectric properties of the material under the influence of a magnetic field. The salient feature of this setup is in its incorporation with the already existing experimental facilities

Magneto-optic and electro-optic modulators

International Nuclear Information System (INIS)

Hutchinson, D.P.; Ma, C.H.; Price, T.R.; Staats, P.A.; Sluis, K.L.V.

1982-01-01

An important aspect of the Faraday rotation diagnostic for tokamak plasma measurement has been the development of suitable polarization modulators for submillimeter wavelength. The problems are to obtain high optical transmission and fast modulation frequencies. In ORNL, the authors have developed both a magneto-optic and an electro-optic submillimeter-wave modulators. These devices have been operated at modulation frequency of approximately 100 kHz, and both have high transmission. The original magneto-optic modulator consists of a 3 mm thick by 1.4 cm diameter 2-111 ferrite disk mounted at the center of an air core coil. Recently, a new ferrite modulator has been tested, which allows a much higher modulation frequency than the original device. A laboratory set-up designed to simulate a plasma heterodyne interferometer/polarimeter experiment has been used to determine the modulator characteristics. A mechanical polarization rotor was used to simulate the rotation by plasma. The transmission of the ferrite disk was 80 % at a wavelength of 0.447 mm. The authors have also performed preliminary measurement on an electro-optic modulator first demonstrated by Fetterman at Lincoln Laboratory, U.S. This device is a classical electro-optic modulator using a cryogenically cooled (4.2 K) LiTaO 3 crystal. Experiments are underway to determine the electro-optic properties of the crystal over the temperature range from 4.2 K to 77 K and over the range of wavelength from 0.118 mm to 0.447 mm. (Wakatsuki, Y.)

Infrared magneto-spectroscopy of two-dimensional and three-dimensional massless fermions: A comparison

Energy Technology Data Exchange (ETDEWEB)

Orlita, M., E-mail: milan.orlita@lncmi.cnrs.fr [Laboratoire National des Champs Magnétiques Intenses, CNRS-UJF-UPS-INSA, 38042 Grenoble (France); Faculty of Mathematics and Physics, Charles University, Ke Karlovu 5, 121 16 Prague 2 (Czech Republic); Faugeras, C.; Barra, A.-L.; Martinez, G.; Potemski, M. [Laboratoire National des Champs Magnétiques Intenses, CNRS-UJF-UPS-INSA, 38042 Grenoble (France); Basko, D. M. [LPMMC UMR 5493, Université Grenoble 1/CNRS, B.P. 166, 38042 Grenoble (France); Zholudev, M. S. [Laboratoire Charles Coulomb (L2C), UMR CNRS 5221, GIS-TERALAB, Université Montpellier II, 34095 Montpellier (France); Institute for Physics of Microstructures, RAS, Nizhny Novgorod GSP-105 603950 (Russian Federation); Teppe, F.; Knap, W. [Laboratoire Charles Coulomb (L2C), UMR CNRS 5221, GIS-TERALAB, Université Montpellier II, 34095 Montpellier (France); Gavrilenko, V. I. [Institute for Physics of Microstructures, RAS, Nizhny Novgorod GSP-105 603950 (Russian Federation); Mikhailov, N. N.; Dvoretskii, S. A. [A.V. Rzhanov Institute of Semiconductor Physics, Siberian Branch, Russian Academy of Sciences, Novosibirsk 630090 (Russian Federation); Neugebauer, P. [Institut für Physikalische Chemie, Universität Stuttgart, Pfaffenwaldring 55, 70569 Stuttgart (Germany); Berger, C. [School of Physics, Georgia Institute of Technology, Atlanta, Georgia 30332 (United States); Institut Néel/CNRS-UJF BP 166, F-38042 Grenoble Cedex 9 (France); Heer, W. A. de [School of Physics, Georgia Institute of Technology, Atlanta, Georgia 30332 (United States)

2015-03-21

Here, we report on a magneto-optical study of two distinct systems hosting massless fermions—two-dimensional graphene and three-dimensional HgCdTe tuned to the zero band gap condition at the point of the semiconductor-to-semimetal topological transition. Both materials exhibit, in the quantum regime, a fairly rich magneto-optical response, which is composed from a series of intra- and interband inter-Landau level resonances with for massless fermions typical √(B) dependence. The impact of the system's dimensionality and of the strength of the spin-orbit interaction on the optical response is also discussed.

Ontario Hydro annual report 1986

International Nuclear Information System (INIS)

1987-04-01

Ontario Hydro's annual report of the financial position and activities for the year 1986 consists of their financial highlights; corporate profile; customer service and satisfaction; message from Chairman; message from President; 1986 in review; financial section; management report; five-year summary of financial statistics; and comparative statistics

Economically viable and environment-friendly hydro energy in Estonia

International Nuclear Information System (INIS)

Saks, Ants; Velner, Harald

2001-01-01

Hydro energy has been in oblivion in Estonia for about 30 years now. During the 1960s, most of Estonia's small hydropower plants were closed down, just as it was done in the whole Soviet Union. As the only larger hydro plant, the 125 MW plant in Narva, was situated on the Russian side of the Narva River, there were only two or three small hydro plants left. Even those were exploited at low capacity and mainly for heating the buildings. It was not until the 1990s that a number of enthusiasts started to re-establish the hydro plants by reconstructing old installations. The pre-feasibility study 'Hydropower in Estonia' proposed by Estonian and Swedish experts, showed that the restoration of the hydropower plants and watermills is economically feasible and technically possible if advanced technology is used. Hydropower as an alternative ('green') energy source should be used in the best technical-economical way. The first pilot plant in Estonia, the 200 kW Kamari plant was constructed in 1998 with compact-propeller units, in co-operation with Waterpumps WP Oy and ABB. Today, ten new plants have been constructed or are under construction. Hydropower plants/watermills should be reconstructed in accordance with the legislative acts on environment protection

Environmental impact and benefit from hydro-energy: Bulgarian case

International Nuclear Information System (INIS)

Vesselinov, V.; Iotova, A.

1996-01-01

The present hydro energy system in Bulgaria has been constructed mainly in the period 1950-1965. The currently utilized hydro-power potential, only 33% of the estimated technical potential, includes 87 HPP operating in 1991. A complex assessment of the environmental impact of the hydro energy objects as well as a comparative analysis of all energy sources in Bulgaria is made in the framework of Bulgarian Case Study of the DECADES Inter-Agency Project. The main types of environmental impact related to HPP operation are presented in 7 specific categories: land requirements, changes in the landscape, hydrological changes, micro-climatic changes, geodynamic changes, risk from man-made activities; generation of new ecosystems. A technique of expertise in ball is proposed as a suitable quantitative approach for more precise assessment of impact on climate factors from different energy sources. 2 tabs., 5 refs

The hydro digest

Energy Technology Data Exchange (ETDEWEB)

Scheil, Hermann [Itaipu Mondig, Power Generation Group (KWU), Siemens AG, Erlangen (Germany)

2000-12-01

Digest WK is an analysis and diagnostics system for turbine generators in large hydroelectric plant: it was developed from the Digest system which has been used in steam turbine plants for many years. The system is in use at the world's biggest hydro plant in Itaipu Binacional between Paraguay and Brazil. The system is described under the sub-headings of (a) monitoring concept; (b) the Digest WK system; (c) vibration monitoring; (d) generator temperature analysis and (e) outlook.

Vaksvikelva small hydro

OpenAIRE

Loe, Daniel Aarset

2017-01-01

Norway is in constant need of renewable energy, and hydroelectric power is still the main source. A great future potential can be found in countless small rivers scattered across the country, which could be developed through small hydro projects. In the process of converting mechanical movement - flowing water - into electric energy, about 5% turns into heat. From a power plant with an annual production of 15 GWh, this means energy enough to heat approximately 30 households is lost. In my pro...

Hydro Ottawa achieves Smart Meter milestone

International Nuclear Information System (INIS)

Anon.

2008-01-01

As Ontario's second largest municipal electricity company, Hydro Ottawa serves more than 285,000 residential and business customers in the city of Ottawa and the village of Casselman. Since 2006, the utility has installed more than 230,000 Smart Meters throughout its service territory in an effort to provide better services to its customers. This initiative represents the largest operational advanced metering infrastructure network in Canada. This move was necessary before time-of-use rates can be implemented in Ottawa. The Smart Meters deliver data wirelessly to Hydro Ottawa's Customer Information System for billing and eliminating manual readings. The Smart Meters are designed to promote more efficient use of electricity. The Government of Ontario has passed legislation requiring the installation of Smart Meters throughout the province by the end of 2010

Role of Pumped Storage Hydro Resources in Electricity Markets and System Operation: Preprint

Energy Technology Data Exchange (ETDEWEB)

Ela, E.; Kirby, B.; Botterud, A.; Milostan, C.; Krad, I.; Koritarov, V.

2013-05-01

The most common form of utility- sized energy storage system is the pumped storage hydro system. Originally, these types of storage systems were economically viable simply because they displace more expensive generating units. However, over time, as those expensive units became more efficient and costs declined, pumped hydro storage units no longer have the operational edge. As a result, in the current electricity market environment, pumped storage hydro plants are struggling. To offset this phenomenon, certain market modifications should be addressed. This paper will introduce some of the challenges faced by pumped storage hydro plants in today's markets and purpose some solutions to those problems.

A long-term analysis of pumped hydro storage to firm wind power

International Nuclear Information System (INIS)

Foley, A.M.; Leahy, P.G.; Li, K.; McKeogh, E.J.; Morrison, A.P.

2015-01-01

Highlights: • This is a long term generation analysis of a high wind power system. • A high CO 2 and fossil fuel price is closest to Ireland’s EU ETS 2020 target. • New pumped storage to firm wind is limited unless strong market costs exist. • Reserve for wind power show that ancillary services are relevant for balancing. - Abstract: Although pumped hydro storage is seen as a strategic key asset by grid operators, financing it is complicated in new liberalised markets. It could be argued that the optimum generation portfolio is now determined by the economic viability of generators based on a short to medium term return on investment. This has meant that capital intensive projects such as pumped hydro storage are less attractive for wholesale electricity companies because the payback periods are too long. In tandem a significant amount of wind power has entered the generation mix, which has resulted in operating and planning integration issues due to wind’s inherent uncertain, varying spatial and temporal nature. These integration issues can be overcome using fast acting gas peaking plant or energy storage. Most analysis of wind power integration using storage to date has used stochastic optimisation for power system balancing or arbitrage modelling to examine techno-economic viability. In this research a deterministic dynamic programming long term generation expansion model is employed to optimise the generation mix, total system costs and total carbon dioxide emissions, and unlike other studies calculates reserve to firm wind power. The key finding of this study is that the incentive to build capital-intensive pumped hydro storage to firm wind power is limited unless exogenous market costs come very strongly into play. Furthermore it was demonstrated that reserve increases with increasing wind power showing the importance of ancillary services in future power systems

Magneto-plasma separating technologies and their possible application for conversion spent fuel and radioactive waste

International Nuclear Information System (INIS)

Kovtun, Yu.V.; Skyibenko, Je.Yi.; Yuferov, V.B.

2007-01-01

A problem of spent fuel (SF) and radioactive waste (RAW) processing is considered in the views of using magneto-plasma technologies. Basing on this analysis, the block-diagram of RAW processing by the technology using a magneto-plasma separator is offered. The paper describes the device for material element separation, where the main physical mechanism of plasma formation and heating are collective processes involved by the plasma-beam interaction. The dimensions of a pilot-separating device are determined

Design and Development of a Magneto-Optic Sensor for Magnetic Field Measurements

Directory of Open Access Journals (Sweden)

Sarbani CHAKRABORTY

2015-01-01

Full Text Available A magneto-optic sensor is developed using a Terbium Doped Glass (TDG element as a Faraday rotation sensor and optical fiber as light transmitting and receiving medium. Online LabView based application software is developed to process the sensor output. The system is used to sense the magnetic field of a DC motor field winding in industrial environment. The sensor output is compared with the magnetic flux density variation obtained with a calibrated Hall Magnetic sensor (Gauss Meter. A linear variation of sensor output over wide range of current passing through the field winding is obtained. Further the results show an improved sensitivity of magneto-optic sensor over the Hall sensor.

Electrodeposition to construct free-standing chitosan/layered double hydroxides hydro-membrane for electrically triggered protein release.

Science.gov (United States)

Zhao, Pengkun; Zhao, Yanan; Xiao, Ling; Deng, Hongbing; Du, Yumin; Chen, Yun; Shi, Xiaowen

2017-10-01

In this study, we report the electrodeposition of a chitosan/layered double hydroxides (LDHs) hydro-membrane for protein release triggered by an electrical signal. The electrodeposition was performed in a chitosan and insulin loaded LDHs suspension in the absence of salt. A free-standing chitosan/LDHs hydro-membrane was generated on the electrode with improved mechanical properties, which is dramatically different from the weak hydrogel deposited in the presence of salt. The amount of LDHs in the hydro-membrane affects the optical transmittance and multilayered structure of the hybrid membrane. Compared to the weak chitosan/LDHs hydrogel, the hydro-membrane has a higher insulin loading capacity and the release of insulin is relatively slow. By biasing electrical potentials to the hydro-membrane, the release behavior of insulin can be adjusted accordingly. In addition, the chitosan/LDHs hydro-membrane showed no toxicity to cells. Our results provide a facile method to construct a chitosan/LDHs hybrid multilayered hydro-membrane and suggest the great potential of the hydro-membrane in controlled protein release. Copyright © 2017 Elsevier B.V. All rights reserved.

The Design of High Efficiency Crossflow Hydro Turbines: A Review and Extension

Directory of Open Access Journals (Sweden)

Ram Adhikari

2018-01-01

Full Text Available Efficiency is a critical consideration in the design of hydro turbines. The crossflow turbine is the cheapest and easiest hydro turbine to manufacture and so is commonly used in remote power systems for developing countries. A longstanding problem for practical crossflow turbines is their lower maximum efficiency compared to their more advanced counterparts, such as Pelton and Francis turbines. This paper reviews the experimental and computational studies relevant to the design of high efficiency crossflow turbines. We concentrate on the studies that have contributed to designs with efficiencies in the range of 88–90%. Many recent studies have been conducted on turbines of low maximum efficiency, which we believe is due to misunderstanding of design principles for achieving high efficiencies. We synthesize the key results of experimental and computational fluid dynamics studies to highlight the key fundamental design principles for achieving efficiencies of about 90%, as well as future research and development areas to further improve the maximum efficiency. The main finding of this review is that the total conversion of head into kinetic energy in the nozzle and the matching of nozzle and runner designs are the two main design requirements for the design of high efficiency turbines.

Magneto-Ionic Control of Interfacial Magnetic Anisotorpy

Science.gov (United States)

Bauer, Uwe; Emori, Satoru; Beach, Geoffrey

2014-03-01

Voltage control of magnetism could bring about revolutionary new spintronic memory and logic devices. Here, we examine domain wall (DW) dynamics in ultrathin Co films and nanowires under the influence of a voltage applied across a gadolinium oxide gate dielectric that simultaneously acts as an oxygen ion conductor. We investigate two electrode configurations, one with a continuous gate dielectric and the other with a patterned gate dielectric which exhibits an open oxide edge right underneath the electrode perimeter. We demonstrate that the open oxide edge acts as a fast diffusion path for oxygen ions and allows voltage-induced switching of magnetic anisotropy at the nanoscale by modulating interfacial chemistry rather than charge density. At room temperature this effect is limited to the vicinity of the open oxide edge, but at a temperature of 100°C it allows complete control over magnetic anisotropy across the whole electrode area, due to higher oxygen ion mobility at elevated temperature. We then harness this novel ``magneto-ionic'' effect to create unprecedentedly strong voltage-induced anisotropy modifications of 3000 fJ/Vm and create electrically programmable DW traps with pinning strengths of 650 Oe, enough to bring to a standstill DWs travelling at speeds of at least 20 m/s. This work is supported by the National Science Foundation through grant ECCS-1128439.

Magneto-exciton transitions in laterally coupled quantum dots

Science.gov (United States)

Barticevic, Zdenka; Pacheco, Monica; Duque, Carlos A.; Oliveira, Luiz E.

2008-03-01

We present a study of the electronic and optical properties of laterally coupled quantum dots. The excitonic spectra of this system under the effects of an external magnetic field applied perpendicular to the plane of the dots is obtained, with the potential of every individual dot taken as the superposition of a quantum well potential along the axial direction with a lateral parabolic confinement potential, and the coupled two- dot system then modeled by a superposition of the potentials of each dot, with their minima at different positions and truncated at the intersection plane. The wave functions and eigenvalues are obtained in the effective-mass approximation by using an extended variational approach in which the magneto- exciton states are simultaneously obtained [1]. The allowed magneto-exciton transitions are investigated by using circularly polarized radiation in the plane perpendicular to the magnetic field. We present results on the excitonic absorption coefficient as a function of the photon energy for different geometric quantum-dot confinement and magnetic-field values. Reference: [1] Z. Barticevic, M. Pacheco, C. A. Duque and L. E. Oliveira, Phys. Rev. B 68, 073312 (2003).

Observation of the X-ray magneto-optical voigt effect

Czech Academy of Sciences Publication Activity Database

Mertins, H. Ch.; Oppeneer, P. M.; Kuneš, Jan; Gaupp, A.; Abramsohn, D.; Schäfers, F.

2001-01-01

Roč. 87, č. 4 (2001), s. 047401-1-047401-4 ISSN 0031-9007 Grant - others:-(DE) ERB FMG ECT /980105 Institutional research plan: CEZ:A02/98:Z1-010-914 Keywords : x-ray magneto-optical Voigt effect Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 6.668, year: 2001

A study on the hydrotreating of coal hydro liquefaction residue and its kinetics

Energy Technology Data Exchange (ETDEWEB)

Huang, J.; Lu, X.; Zhang, D.; Gao, J. [Department of Chemical Engineering for Energy Resources, East China University of Science and Technology, Shanghai (China)

2010-09-15

Hydro-conversion of coal hydro liquefaction residue obtained from a 6 t/day pilot plant of Shenhua Group in Shanghai was carried out under the hydrotreating condition. The coal hydro liquefaction residue and its product were extracted in sequence with n-hexane, toluene and tetrahydrofuran in a Soxhlet apparatus. The n-hexane soluble fractions increased with the increase of reaction temperature and time. Its amount increased from 14.14% to a maximum of 40.86% under the conditions of 470 {sup o}C and 30 min, which meant that moderate extension of coal residence time in the coal hydro liquefaction reactor is beneficial to the increase of oil yield. A 4-lumped kinetic model of coal hydro liquefaction residue hydro-conversion was performed using solubility-based lumped fractions. In the model, the tetrahydrofuran insoluble fractions were classified into two parts: easily reactive part and unreactive part. The kinetic parameters were estimated by a fourth-order Runge-Kutta method and a nonlinear least squares method, and the apparent activation energies were calculated according to the Arrhenius Equation. A large quantity of total catalyst consisting of remained liquefaction catalyst, part of the mineral from raw coal and additive Fe-based catalyst could considerably reduce the apparent activation energy of hydro-conversion for the toluene insoluble/tetrahydrofuran insoluble fractions to 36.79 kJ-mol{sup -1}. The calculated values of the model coincided well with the experimental values. (authors)

Hydro power plants, an overview of the current types and technology

Directory of Open Access Journals (Sweden)

Tkáč Štefan

2018-03-01

Full Text Available Despite the long history of hydropower technology and rising number of system harvesting energy from alternative sources, the constant research within hydro power sector becoming increasingly important as the power from water was and still is the leading alternative source of green energy generation, capitalized not necessarily within micro-urban structures only. The advantages of hydro systems involve their relatively low acquisition cost against durability, the possibility of gaining energy independence, relatively high flexibility and adaptability for spatial conditions and energy demands of the end users. Nowadays micro hydro systems could capitalize head range starting at 100cm and the efficiency of hydro systems in general ranges between 65-75% in micro and small applications climbing up to 96% in macro designs. It is mostly due to flexibility in applications, adaptability in combinations with other renewable energy systems and the ability to generate clean, stable, thus reliable energy that makes technical development the most vibrant and noticeable in the micro sphere.

Parametric distribution approach for flow availability in small hydro potential analysis

Science.gov (United States)

Abdullah, Samizee; Basri, Mohd Juhari Mat; Jamaluddin, Zahrul Zamri; Azrulhisham, Engku Ahmad; Othman, Jamel

2016-10-01

Small hydro system is one of the important sources of renewable energy and it has been recognized worldwide as clean energy sources. Small hydropower generation system uses the potential energy in flowing water to produce electricity is often questionable due to inconsistent and intermittent of power generated. Potential analysis of small hydro system which is mainly dependent on the availability of water requires the knowledge of water flow or stream flow distribution. This paper presented the possibility of applying Pearson system for stream flow availability distribution approximation in the small hydro system. By considering the stochastic nature of stream flow, the Pearson parametric distribution approximation was computed based on the significant characteristic of Pearson system applying direct correlation between the first four statistical moments of the distribution. The advantage of applying various statistical moments in small hydro potential analysis will have the ability to analyze the variation shapes of stream flow distribution.

Hydro power plants, an overview of the current types and technology

Science.gov (United States)

Tkáč, Štefan

2018-03-01

Despite the long history of hydropower technology and rising number of system harvesting energy from alternative sources, the constant research within hydro power sector becoming increasingly important as the power from water was and still is the leading alternative source of green energy generation, capitalized not necessarily within micro-urban structures only. The advantages of hydro systems involve their relatively low acquisition cost against durability, the possibility of gaining energy independence, relatively high flexibility and adaptability for spatial conditions and energy demands of the end users. Nowadays micro hydro systems could capitalize head range starting at 100cm and the efficiency of hydro systems in general ranges between 65-75% in micro and small applications climbing up to 96% in macro designs. It is mostly due to flexibility in applications, adaptability in combinations with other renewable energy systems and the ability to generate clean, stable, thus reliable energy that makes technical development the most vibrant and noticeable in the micro sphere.

About the magneto-acoustic instabilities in mirrors

International Nuclear Information System (INIS)

Zvonkov, A.V.; Timofeev, A.V.

1984-01-01

It is shown that the characteristic of a plasma in mirrors anisotropy of io on distribution function versus velocities may results in the drive of magneto-acoustic instabilities. This instability, in contast to the well known Alyven oscillation instability, is driven on ion cyclotron frequency harmonics The instability in question has been possibly observed during the experiments a at the tmx device, where the oscillations have been excited both at the ion cycl tron frequency and harmonics

Short-term hydro-thermal scheduling using particle swarm optimization method

International Nuclear Information System (INIS)

Yu, Binghui; Yuan, Xiaohui; Wang, Jinwen

2007-01-01

The approaches based on different particle swarm optimization (PSO) techniques are applied to solve the short-term hydro-thermal scheduling problem. In the proposed methods, many constraints of the hydro-thermal system, such as power balance, water balance, reservoir volume limits and the operation limits of hydro and thermal plants, are considered. The feasibility of the proposed algorithm is demonstrated through an example system, and the results are compared with the results of a genetic algorithm and evolutionary programming approaches. The experimental results show that all the PSO algorithms have the ability to achieve nearly global solutions, but a local version of PSO with inertia weight appears to be the best amongst all the PSOs in terms of high quality solution

Ontario Hydro's transportation of radioactive material and emergency response plan

International Nuclear Information System (INIS)

Karmali, N.

1993-01-01

Ontario Hydro has been transporting radioactive material for almost 30 years without any exposure to the public or release to the environment. However, there have been three accidents involving Hydro's shipments of radioactive material. In addition to the quality packaging and shipping program, Ontario Hydro has an Emergency Response Plan and capability to deal with an accident involving a shipment of radioactive material. The Corporation's ability to respond, to effectively control and contain the situation, site remediation, and to provide emergency public information in the event of a road accident minimizes the risk to the public and the environment. This emphasizes their commitment to worker safety, public safety and impact to the environment. Response capability is mandated under various legislation and regulations in Canada

Development of HydroImage, A User Friendly Hydrogeophysical Characterization Software

Energy Technology Data Exchange (ETDEWEB)

Mok, Chin Man [GSI Environmental; Hubbard, Susan [Lawrence Berkeley National Laboratory; Chen, Jinsong [Lawrence Berkeley National Laboratory; Suribhatla, Raghu [AMEC E& I; Kaback, Dawn Samara [AMEC E& I

2014-01-29

HydroImage, user friendly software that utilizes high-resolution geophysical data for estimating hydrogeological parameters in subsurface strate, was developed under this grant. HydroImage runs on a personal computer platform to promote broad use by hydrogeologists to further understanding of subsurface processes that govern contaminant fate, transport, and remediation. The unique software provides estimates of hydrogeological properties over continuous volumes of the subsurface, whereas previous approaches only allow estimation of point locations. thus, this unique tool can be used to significantly enhance site conceptual models and improve design and operation of remediation systems. The HydroImage technical approach uses statistical models to integrate geophysical data with borehole geological data and hydrological measurements to produce hydrogeological parameter estimates as 2-D or 3-D images.

HydroCoil as an adjuvant to bare platinum coil treatment of 100 cerebral aneurysms

International Nuclear Information System (INIS)

Fanning, Noel F.; Berentei, Zsolt; Brennan, Paul R.; Thornton, John

2007-01-01

Introduction The overall safety of the HydroCoil, an expansile hybrid hydrogel-platinum coil, is unknown. We report a prospective observational study of our first 100 cerebral aneurysms treated with HydroCoils, focusing on safety and initial efficacy.Methods Indications, procedural complications, clinical and angiographic outcomes were recorded. Packing density, number of coils deployed and angiographic results were compared with those in a matched control group of 100 aneurysms treated solely with bare platinum coils. HydroCoil complication rates were compared to bare platinum coil rates at our institution and in published series. Results Adjuvant HydroCoil treatment led to increased mean percentage aneurysm filling compared to controls (50 ± 21% versus 27 ± 13%, P < 0.001). Immediate posttreatment angiographic results showed significantly (P < 0.001) more complete occlusions and fewer incomplete (<95%) occlusions compared to controls. Intermediate follow-up angiograms (median 7.5 months) in 63 aneurysms showed a trend towards fewer incomplete occlusions with HydroCoil treatment. There were significantly fewer major recurrences with HydroCoil treatment compared to the control treatment (9.5% versus 22.6%, P 0.046). In the adjuvant HydroCoil group, major recurrent aneurysms had significantly less percentage volume packing with HydroCoils than non-recurrent aneurysms (50.3 ± 5.0% versus 65.3 ± 18.0%, P = 0.04). There was a 12% procedural complication rate, 6% procedural morbidity and 1% mortality rate, similar to institutional and reported bare platinum coil complication rates.Conclusion HydroCoils can be safely deployed with a similar complication rate to bare platinum coils. They result in improved aneurysm filling. Intermediate follow-up angiography showed significantly fewer major recurrences. Long-term follow-up is required to confirm initial improved stability. (orig.)

Study of cavitation in hydro turbines. A review

Energy Technology Data Exchange (ETDEWEB)

Kumar, Pardeep; Saini, R.P. [Alternate Hydro Energy Centre, Indian Institute of Technology, Roorkee 247667 (India)

2010-01-15

Reaction turbines basically Francis turbines and propeller/Kaplan turbines are suitable for medium and low head hydropower sites. The management of the small hydropower plants is an important factor, for achieving higher efficiency of hydro turbines with time. Turbines show declined performance after few years of operation, as they get severely damaged due to various reasons. One of the important reasons is erosive wear of the turbines due to cavitation. Reaction turbines, however are more prone to cavitation especially Francis turbines where a zone in the operating range is seriously affected by cavitation and considered as forbidden zone. Cavitation is a phenomenon which manifests itself in the pitting of the metallic surfaces of turbine parts because of the formation of cavities. In the present paper, studies undertaken in this field by several investigators have been discussed extensively. Based on literature survey various aspects related to cavitation in hydro turbines, different causes for the declined performance and efficiency of the hydro turbines and suitable remedial measures suggested by various investigators have been discussed. (author)

Hydro-Thermal Fatigue Resistance Measurements on Polymer Interfaces

Science.gov (United States)

Gurumurthy, Charan K.; Kramer, Edward J.; Hui, Chung-Yuen

1998-03-01

We have developed a new technique based on a fiber optic displacement sensor for rapid determination of hydro-thermal fatigue crack growth rate per cycle (da/dN) of an epoxy/polyimide interface used in flip chip attach microelectronic assembly. The sample is prepared as a trilayered cantilever beam by capillary flow of the epoxy underfill over a polyimide coated metallic beam. During hydro-thermal cycling the crack growth along the interface (from the free end) changes the displacement of this end of the beam and we measure the free end displacement at the lowest temperature in each hydro-thermal cycle. The change in beam displacement is then converted into crack growth rate (da/dN). da/dN depends on the maximum change in the strain energy release rate of the crack and the phase angle in each cycle. The relation between da/dN and maximum strain energy release rate characterizes the fatigue crack growth resistance of the interface. We have developed and used a simple model anhydride cured and a commercially available PMDA/ODA passivation for this study.

Dispersion formulae for waves in a magneto-active relativistic plasma

International Nuclear Information System (INIS)

Misra, P.; Mohanty, J.N.

1980-01-01

Dispersion formulae are derived for the transverse waves propagating through a collisionless magneto-active plasma in the direction of the magnetic field valid for relativistic as well as non-relativistic temperatures. Wave propagation under various limiting conditions of temperatures and magnetic field are discussed. (author)

Dispersion formulae for waves in a magneto-active relativistic plasma

Energy Technology Data Exchange (ETDEWEB)

Misra, P. (Ravenshaw Coll., Cuttack (India)); Mohanty, J.N. (F.M. College, Balasore (India). Dept. of Physics)

1980-12-01

Dispersion formulae are derived for the transverse waves propagating through a collisionless magneto-active plasma in the direction of the magnetic field valid for relativistic as well as non-relativistic temperatures. Wave propagation under various limiting conditions of temperatures and magnetic field are discussed.

Rapid DNA multi-analyte immunoassay on a magneto-resistance biosensor

NARCIS (Netherlands)

Koets, M.; Wijk, van der T.; Eemeren, van J.T.W.M.; Amerongen, van A.; Prins, M.W.J.

2009-01-01

We present the rapid and sensitive detection of amplified DNA on a giant magneto-resistance sensor using superparamagnetic particles as a detection label. The one-step assay is performed on an integrated and miniaturized detection platform suitable for application into point-of-care devices. A

Challenging hydro-hegemony

DEFF Research Database (Denmark)

Wessels, Josepha Ivanka

2015-01-01

Bank. Both case studies show that control over water resources and supply provides political power over others at local level. Yet non-violent resistance can be observed in these border areas. In border areas between Israel, Syria and Palestine, control over access and water supply plays an important...... role in the ability of Israel to exercise hegemonic power in daily hydro-politics, which in the long term is detrimental for the people and the environment and disrupts the hydrological balance in the entire Jordan River basin....

Economic impact of Hydro-Quebec's nuclear activities

International Nuclear Information System (INIS)

Emard, R.

1994-01-01

Gentilly 2 nuclear power plant has benefited the regions of Becancour and Trois Rivieres, with spin-off at the provincial level. Gentilly 2 is Hydro Quebec's only nuclear plant. Its 675 MW provide nearly 3% of Hydro Quebec's production. Over 664 permanent jobs were created, 70% of them highly specialized and multi-skilled. In 1993, out of C$99 spent, 57.3 were for wages, 16.3 for equipment and supplies (including fuel and heavy water), 18 for professional services provided by AECL and others, and the remainder included fees, permits, contract work, and miscellaneous. Gentilly 2 has fostered technological development and inventions which are used at other CANDU stations. 7 ills

Hydro-Quebec opens up, expects positive reaction from FERC

International Nuclear Information System (INIS)

McArthur, D.; Salaff, S.

1997-01-01

Hydro-Quebec Energy Services US (HQUS), the marketing arm of Hydro-Quebec, amended its application for a power marketing licence with the Federal Energy Regulatory Commission (FERC), by offering to open up five per cent of the wholesale Quebec electricity market to competition. The Corporation hopes that its revised application will satisfy FERC to grant HQUS a power marketer licence, with the right to sell electricity in the US at market-based rates. Hydro-Quebec insiders believe that in addition to opening up the market to competition, thereby equalizing market conditions on both sides of the border, the Corporation's chances of receiving the licence also have been improved by the creation of the provincial energy board (Regie de l'energie) which in future will regulate electricity and gas transmission through Quebec, and establish transmission tariffs. FERC ruling is expected within 60 days of the March 7, 1997 amended application

Magnetic thaw-down and boil-off due to magneto acceptors in 2DEG

Energy Technology Data Exchange (ETDEWEB)

Chaubet, C.; Raymond, A. [L2C UMR 5221, CNRS-Université Montpellier 2, Place E. Bataillon, 34090 Montpellier cedex 05 (France); Bisotto, I. [LNCMI, UPR 3228, CNRS-INSA-UJF-UPS, BP166, 38042 Grenoble, Cedex 9 (France); Harmand, J. C. [LPN, CNRS, route de Nozay, 91460 Marcoussis (France); Kubisa, M. [Institute of Physics, Wroclaw University of Technology, 50-370 Wroclaw (Poland); Zawadzki, W. [Institute of Physics, Polish Academy of Sciences, 02668 Warsaw (Poland)

2013-12-04

The Quantum Hall Effect (QHE) and Shubnikov-de Haas effect are investigated experimentally using n type modulation-doped GaAs/GaAlAs quantum wells (QWs) additionally doped in the well with beryllium acceptor atoms. It is presently shown that the localized magneto-acceptor (MA) states which possess discrete energies above the corresponding Landau levels (LLs) lead to two observable effects in magneto-transport: magnetic thaw-down and magnetic boil-off of 2D electrons. Both effects are related to the fact that electrons occupying the localized MA states cannot conduct. Thus in the thaw-down effect the electrons fall down from the MA states to the free Landau states. This leads to a shift of the Hall plateau towards higher magnetic fields as a consequence of an increase of the 2D electron density N{sub S}. In the boil-off effect the electrons are pushed from the free Landau states to the empty MA states under high enough Hall electric field. This process has an avalanche character leading to a dramatic increase of magneto-resistance, consequence of a decrease of N{sub S}.

Magneto-optical trap for metastable helium at 389 nm

NARCIS (Netherlands)

Koelemeij, J.C.J.; Stas, R.J.W.; Hogervorst, W.; Vassen, W.

2003-01-01

We have constructed a magneto-optical trap (MOT) for metastable triplet helium atoms utilizing the 2 S-3(1)-->3 P-3(2) line at 389 nm as the trapping and cooling transition. The far-red-detuned MOT (detuning Delta=-41 MHz) typically contains few times 10(7) atoms at a relatively high (similar

Curie temperature, exchange integrals, and magneto-optical properties in off-stoichiometric bismuth iron garnet epitaxial films

Science.gov (United States)

Vertruyen, B.; Cloots, R.; Abell, J. S.; Jackson, T. J.; da Silva, R. C.; Popova, E.; Keller, N.

2008-09-01

We have studied the influence of the stoichiometry on the structural, magnetic, and magneto-optical properties of bismuth iron garnet (Bi3Fe5O12) thin films grown by pulsed laser deposition. Films with different stoichiometries have been obtained by varying the Bi/Fe ratio of the target and the oxygen pressure during deposition. Stoichiometry variations influence the Curie temperature TC by tuning the (Fe)-O-[Fe] geometry: TC increases when the lattice parameter decreases, contrary to what happens in the case of stoichiometric rare-earth iron garnets. The thermal variation of the magnetization, the Faraday rotation, and the Faraday ellipticity have been analyzed in the frame of the Néel two-sublattice magnetization model giving energies of -48K (4.1 meV), -29K (2.5 meV), and 84 K (7.3 meV) for the three magnetic exchange integrals jaa , jdd , and jad , respectively. Magneto-optical spectroscopy linked to compositional analysis by Rutherford backscattering spectroscopy shows that Bi and/or Fe deficiencies also affect the spectral variation (between 1.77 and 3.1 eV). Our results suggest that bismuth deficiency has an effect on the magneto-optical response of the tetrahedral Fe sublattice, whereas small iron deficiencies affect predominantly the magneto-optical response of the octahedral sublattice.

Magneto-inertial Fusion: An Emerging Concept for Inertial Fusion and Dense Plasmas in Ultrahigh Magnetic Fields

Energy Technology Data Exchange (ETDEWEB)

Thio, Francis Y.C.

2008-01-01

An overview of the U.S. program in magneto-inertial fusion (MIF) is given in terms of its technical rationale, scientific goals, vision, research plans, needs, and the research facilities currently available in support of the program. Magneto-inertial fusion is an emerging concept for inertial fusion and a pathway to the study of dense plasmas in ultrahigh magnetic fields (magnetic fields in excess of 500 T). The presence of magnetic field in an inertial fusion target suppresses cross-field thermal transport and potentially could enable more attractive inertial fusion energy systems. A vigorous program in magnetized high energy density laboratory plasmas (HED-LP) addressing the scientific basis of magneto-inertial fusion has been initiated by the Office of Fusion Energy Sciences of the U.S. Department of Energy involving a number of universities, government laboratories and private institutions.

Size-dependent electro-magneto-elastic bending analyses of the shear-deformable axisymmetric functionally graded circular nanoplates

Science.gov (United States)

Arefi, Mohammad; Zenkour, Ashraf M.

2017-10-01

This paper develops nonlocal elasticity equations and magneto-electro-elastic relations to size-dependent electro-magneto-elastic bending analyses of the functionally graded axisymmetric circular nanoplates based on the first-order shear deformation theory. All material properties are graded along the thickness direction based on exponential varying. It is assumed that a circular nanoplate is made from piezo-magnetic materials. The energy method and Ritz approach is employed for the derivation of governing equations of electro-magneto-elastic bending and the solution of the problem, respectively. The nanoplate is subjected to applied electric and magnetic potentials at top and transverse loads while it is rested on Pasternak's foundation. Some important numerical results are presented in various figures to show the influence of applied electric and magnetic potentials, small scale parameter and inhomogeneous index of an exponentially graded nanoplate.

Micro-hydro power in the UK: The role of communities in an emerging energy resource

International Nuclear Information System (INIS)

Bracken, L.J.; Bulkeley, H.A.; Maynard, C.M.

2014-01-01

Research around micro-hydro power is focused on technical aspects with limited understanding of the social organisation and environmental implications. We examine the ways in which micro-hydro is engaged by people and organisations as a means of contributing to the UK's policy ambition for renewable energy. We bring to the fore the way in which expertise is used and contested. A web based review of micro-hydro schemes in the UK was undertaken and a detailed evaluation of two schemes in the North of England was conducted to determine how expertise and contestation figures in community schemes. Results demonstrate a rapid expansion of micro-hydro in the UK. Ownership/control is highly ‘community based’. Until now research around micro-hydro has been dominated by technical approaches with schemes defined in terms of hardware. We propose a third dimension to Walker and Cass's (2007) classification of renewable energy developments: the environmental dimension. We suggest this dimension of micro-hydro is critical, both in terms of the extent to which resources can be realised but also the ways in which it might attract controversy, in particular around how expertise is used and valued. - Highlights: • Analysis of micro-hydro schemes in the UK demonstrates a recent rapid expansion. • We propose a third dimension to renewable energy developments: the environmental dimension. • The environmental dimension of micro-hydro determines how resources are realised. • Environmental features underpin the controversy which can emerge around schemes. • The ownership of micro-hydro schemes is highly ‘community based’

Small hydro generation building block profile

International Nuclear Information System (INIS)

2003-01-01

Concise business information on small hydro generation in British Columbia was presented in this document. It was noted that the steep terrain within the province and its abundant precipitation provides numerous opportunities for hydropower generation in British Columbia. The hydroelectric sector produces approximately 90 per cent of the electrical demand in the province. The document focusses on small hydro sites producing between 0.5 and 50 mega watts (MW) and not having large water storage. In the first section, an overview of the electricity sector in the province is provided. The following issues are examined in subsequent sections: land resources; infrastructure requirements; sales market; labour market; the regulatory regime; development factors; non-governmental aspects; investments and economics; the present status and future outlook of the industry; and, government revenue. Input-output tables were also provided. 22 refs., 5 tabs., 4 figs

Implementation and automation of a Faraday experiment for the magneto-optical characterization of ferrofluids

International Nuclear Information System (INIS)

Velásquez, A A; Urquijo, J P

2016-01-01

This work presents the design, assembly and automation of a Faraday experiment for use in characterization of the magneto-optical response of fluids and ferrofluids. The magneto-optical Faraday experiment was automated using programmable equipment, controlled through the IEEE-488 port via Standard Commands for Programmable Instruments executed from a graphical interface developed in LabVIEW software. To calibrate the system the Verdet constants of distilled water and isopropyl alcohol were measured, obtaining an error percentage less than 2% for both fluids. Subsequently we used the system for measuring the Verdet constant of a ferrofluid of iron oxide nanoparticles diluted in distilled water, which was synthesized and, before its dilution, characterized by scanning electron microscopy, room temperature Mössbauer spectroscopy and vibrating sample magnetometry. We found that the Verdet constant of the diluted ferrofluid was smaller than that of distilled water, indicating opposite contributions of the effects of the diamagnetic and paramagnetic phases present in the ferrofluid to the magneto-optical effect. Details of the assembly, control of the experiment and development of the measurements are presented in this paper. (paper)

Investigation of optical and magneto-optical constants and their surface-oxide-layer effects of single-crystalline GdCo2

International Nuclear Information System (INIS)

Lee, S.J.; Kim, K.J.; Canfield, P.C.; Lynch, D.W.

2000-01-01

We investigated the optical and magneto-optical properties of single-crystalline GdCo 2 by spectroscopic ellipsometry (SE) and magneto-optical Kerr spectrometry (MOKS). The diagonal component of the optical conductivity tensor of the compound was obtained by SE in the 1.5-5.5 eV region and the off-diagonal component by using the measured magneto-optical parameters (Kerr rotation and ellipticity) by MOKS and the SE data. The measured spectra were corrected for the surface oxide layer by employing a three-phase model treating the oxide layer as nonmagnetic with constant refractive index. The magnitude of the diagonal component becomes enhanced and the optical transition structures of the off-diagonal component become more pronounced by the oxide correction. The overall optical and magneto-optical data are discussed in terms of the calculated spin-polarized band structure and optical absorption of the compound and the effect of the surface oxide layer

Operational and structural measures to reduce hydro-peaking impact on fish larvae

International Nuclear Information System (INIS)

Kopecki, Ianina; Schneider, Matthias

2016-01-01

Eco-hydraulic investigations studying the effects of hydro-peaking on river biota are gaining in importance. Negative effects of rapid flow fluctuations due to hydro power production are well documented by many studies, with the larvae and juvenile fish identified among the mostly affected life stages. Therefore, elaboration of efficient hydro-peaking mitigation strategies is an important issue for energy companies as well as for water body administrations responsible for the fulfilment of WFD requirements. The present case study strives for practical solutions allowing to minimize or compensate the negative effects of hydro-peaking on the fish fauna of the 7 km long river reach on the river Lech (southern Germany). Model based investigations allow to access the impact from currently authorized discharge regime, suggest operational and structural measures within the reach in terms of reducing the risk of stranding for fish larvae and select the measures most easy to implement and with the largest ecological benefit. The paper describes the approach for accessing the effects of hydro-peaking based on 2D hydrodynamic modelling, fuzzy logic based habitat modelling and information on cutting-edge biological investigations on fish larvae from Lunz experimental facility (Austria). (authors)

Parameterisation effect on the behaviour of a head-dependent hydro chain using a nonlinear model

International Nuclear Information System (INIS)

Catalao, J.P.S.; Mariano, S.J.P.S.; Mendes, V.M.F.; Ferreira, L.A.F.M.

2006-01-01

This paper is on the problem of short-term hydro scheduling (STHS), particularly concerning a head-dependent hydro chain. We use a method based on nonlinear programming (NLP), namely quadratic programming, to consider hydroelectric power generation a function of water discharge and of the head. The method has been applied successfully to solve a test case based on a realistic cascaded hydro system with a negligible computational time requirement and is also applied to show that the role played by reservoirs in the hydro chain do not depend only on their relative position. As a new contribution to earlier studies, which presented reservoir operation rules mainly for medium and long-term planning procedures, we show that the physical data defining hydro chain parameters used in the nonlinear model have an effect on the STHS, implying different optimal storage trajectories for the reservoirs accordingly not only with their position in the hydro chain but also with the new parameterisation defining the data for the hydro system. Moreover, considering head dependency in the hydroelectric power generation, usually neglected for hydro plants with a large storage capacity, provides a better short-term management of the conversion of the potential energy available in the reservoirs into electric energy, which represents a major advantage for the hydroelectric utilities in a competitive electricity market. (author)

[Ontario Hydro]. 1995 corporate budget and 1995--1997 business plan

International Nuclear Information System (INIS)

1995-01-01

Ontario Hydro's corporate mission is to make Ontario Hydro a leader in energy efficiency and sustainable development, and to provide its customers with safe and reliable energy services at competitive prices. This document summarizes the corporation's work and financial results planned for the previous year and forecast for the two following years. It represents a consolidation of business plans prepared by the various business units

[Ontario Hydro]. 1994 corporate budget and 1994--1996 business plan

International Nuclear Information System (INIS)

1994-01-01

Ontario Hydro's Corporate mission is to make Ontario Hydro a leader in energy efficiency and sustainable development, and to provide its customers with safe and reliable energy services at competitive prices. This document summarizes the Corporation's work and financial results planned for the previous year and forecast for the two following years. It represents a consolidation of business plans prepared by the various Business Units

Hydro-Quebec looks to integrated development of Quebec and its regions

International Nuclear Information System (INIS)

Bissonnette, Lise

1995-01-01

Hydro-Quebec's telecommunication system, the largest private telecommunications network in Canada, was discussed. The network was set up to assure safety and efficiency of the power plants and energy transmission and distribution lines. By the year 2000 Hydro-Quebec will need electronic links with all its industrial, commercial and residential customers in order to guarantee competitive service and full customer satisfaction. Investments of about one half billion dollars have been earmarked to boost the capacity of their telecommunications grid and meet steadily growing needs. As a result of the very difficult negotiations to resolve the native land claims issue, Hydro-Quebec was forced to adapt a strict and far-reaching environmental policy, which is now beginning to pay off not only in environmental terms, but also in terms of goodwill among actual and prospective customers. As a result of these huge infrastructure projects Hydro Quebec will be in a position to guarantee people access to energy at a price that is among the lowest in the world. Although demand growth could slow, demand itself will not wane. As part of this overall strategy, Hydro-Quebec plans to defer large-scale projects, instead, for the foreseeable future it will concentrate on smaller power plants, some of which could be built on rivers that have already been tamed

Using ecosystem services to represent the environment in hydro-economic models

Science.gov (United States)

Momblanch, Andrea; Connor, Jeffery D.; Crossman, Neville D.; Paredes-Arquiola, Javier; Andreu, Joaquín

2016-07-01

Demand for water is expected to grow in line with global human population growth, but opportunities to augment supply are limited in many places due to resource limits and expected impacts of climate change. Hydro-economic models are often used to evaluate water resources management options, commonly with a goal of understanding how to maximise water use value and reduce conflicts among competing uses. The environment is now an important factor in decision making, which has resulted in its inclusion in hydro-economic models. We reviewed 95 studies applying hydro-economic models, and documented how the environment is represented in them and the methods they use to value environmental costs and benefits. We also sought out key gaps and inconsistencies in the treatment of the environment in hydro-economic models. We found that representation of environmental values of water is patchy in most applications, and there should be systematic consideration of the scope of environmental values to include and how they should be valued. We argue that the ecosystem services framework offers a systematic approach to identify the full range of environmental costs and benefits. The main challenges to more holistic representation of the environment in hydro-economic models are the current limits to understanding of ecological functions which relate physical, ecological and economic values and critical environmental thresholds; and the treatment of uncertainty.

Magneto-Plasmonic Properties of Au/Fe/Au Planar Nanostructures: Theory and Experiments

Czech Academy of Sciences Publication Activity Database

Vlček, J.; Lesňák, M.; Otipka, P.; Sobota, Jaroslav

2016-01-01

Roč. 12, č. 1 (2016), s. 136-141 ISSN 2211-8128 Institutional support: RVO:68081731 Keywords : magneto-plasmonics * planar nanostructures * response factors Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering

Decision making algorithms for hydro-power plant location

CERN Document Server

Majumder, Mrinmoy

2013-01-01

The present study has attempted to apply the advantage of neuro-genetic algorithms for optimal decision making in maximum utilization of natural resources. Hydro-power is one of the inexpensive, but a reliable source of alternative energy which is foreseen as the possible answer to the present crisis in the energy sector. However, the major problem related to hydro-energy is its dependency on location. An ideal location can produce maximum energy with minimum loss. Besides, such power-plant also requires substantial amount of land which is a precious resource nowadays due to the rapid and unco

Hydro models and salmon recovery in the northwest

International Nuclear Information System (INIS)

Dragoon, K.

1993-01-01

Hydro regulation models provide extensive support for analyzing the efficacy of salmon recovery plans in the Northwest. Power planners developed these computer programs to help plan and efficiently operate a large multiple use river system. The models represent physical relationships and operational requirements on the system. They also simulate coordinated system operations for efficient power generation. These models are being pressed into service to provide data for fish recovery plans. They provide important information about hydro system capabilities and responses to recovery programs. However, the models cannot meet all of the analytical needs of fish biologists working toward salmon recovery

Efficacy of magneto-laser therapy in the treatment of ureaplasma infection

Directory of Open Access Journals (Sweden)

N N Aliev

2018-04-01

Full Text Available Aim. To study clinical and epidemiological data in males and females with ureaplasma infection and to evaluate efficacy of magneto-laser therapy used as additional treatment of ureaplasma infection. Methods. 104 patients (94 men and 10 women with urogenital ureaplasma infection were observed. Patients were divided into two groups: a study group (n=55 that received standard and magneto-laser therapy, and a comparison group (n=49 that received only standard treatment. Polymerase chain reaction was used to investigate samples for Mycoplasma hominis, Ureaplasma parvum and urealyticum, and bacteriological study for Mycoplasma hominis and Ureaplasma spp. was additionally performed with determining their antibiotic susceptibility. Magnetic therapy was conducted with the use of Michelangelo device (Italy for 10 minutes to small pelvis area for 10 days. Results. As a result, 78 (82.9% males were diagnosed with uretritis, 52 (55.3% with prostatitis, 37 (39.3% with cystitis. In females monoinfection was more prevalent than in males (50.0% vs 40.4%. Ureaplasmosis predominantly affected subjects aged 20-29 (97.8% and 30-39 (86.0% years. In female group, patients aged 20-29 years prevailed, while in a male group - patients aged 30-39 years. In males, the association of Ureaplasma with Mycoplasma hominis (36.1% prevailed. Conclusion. Complex treatment of ureaplasma infection of urogenital tract including magneto-laser therapy demonstrated high clinical efficacy and allowed achieving clinical and laboratory cure of ureaplasma infection in 85.4% of cases.