Resonance integral analytical calculation considering shadowing effect
International Nuclear Information System (INIS)
Monteiro, M.A.M.; Martinez, A.S.
1990-01-01
It is presented a method for the Resonance Integral Calculation in the fuel and moderator regions, including the shadowing effect. This effect appears due to the presence of several fuel rods in a infinite moderator region. The method is based on the approximations to the J (ξ, β) function and theirs partial derivatives in relation to β. The dependence of the Resonance Integral in the J (ξ, β) comes from the rational approximation to the neutron escape probability. The final results were obtained in a very simple and fast way, and they show the good accuracy of the method. (author)
The Dependence of the Resonance Integral on the Doppler Effect
Energy Technology Data Exchange (ETDEWEB)
Rosen, J
1960-12-15
The Doppler sensitive contributions to the resonance integral for metal and oxide cylinders have been calculated using tables compiled by Adler, Hinman and Nordheim. The temperatures 20, 200, 350, 500 and 650 deg C have been investigated for the pure metal and 20, 300, 600, 900 and 1200 deg C for the oxide. Contributions from the separate resonances in the resolved region and for certain energies in the unresolved region are accounted for in detail. Integration over adequate statistical distributions has been carried out for the resonance parameters in the unresolved region. The increase in the resonance integral at elevated temperatures due to the Doppler effect is given separately in tables and diagrams.
The Effective Resonance Integral of Thorium Oxide Rods
Energy Technology Data Exchange (ETDEWEB)
Weitman, J
1962-12-15
The effective resonance integral of thorium oxide rods has been determined as a function of their surface to mass ratio. The range of S/M values covered is 0.15 - 0.65 cm/g. An experimental technique based on the comparison of activities obtained in thermal and slowing-down neutron fluxes was employed. The shape of the resonance neutron spectrum was determined from measurements with a fast chopper and from calculations, permitting deduction of a correction factor which relates the experimental values to the ideal 1/E case. The results are summarized by the following expression: RI{sub ThO{sub 2}} (5.0 + 15.6{radical}(S/M{sub ThO{sub 2}})) {+-} 5% The main contribution to the margin of error arises from the uncertainties in the 1.5 % spectral correction applied in the 1.5 b '1/v' part deducted and in the 1520 b infinite dilution integral of gold, used as a standard. In order to compare the consistency of Dresner's first equivalence theorem and Nordheim's numerical calculations relative to our results, the resonance integral values for thorium metal rods obtained previously by Hellstrand and Weitman have been recalculated, using recent cross section and spectrum data. The new formula is Rl{sub Th} = (3.3 + 16.1{radical}(S/M{sub Th})) {+-} 5%. It differs from the old one mainly because of the proved non-1/v behaviour of the thorium cross section below the first resonance.
Energy Technology Data Exchange (ETDEWEB)
Krcevinac, S; Takac, S [Institut za nuklearne nauke ' Boris Kidric' , Vinca, Belgrade (Yugoslavia)
1966-07-01
The analytical theory of resonance absorption, as well as the numerical Monte Carlo method, allows calculation of the resonance integral. However, it is based on specific approximations so it may be used accurately enough in a limited number of cases. Likewise, insufficiently accurate know ledge of the basic nuclear constants (e.g. resonance parameters, etc.) used as input data in analytical calculation, leads to inaccurate determination of the resonance integral.. Therefore, experimental determination of the effective resonance integral is still indispensable. In some cases the experimental results are used as the exclusive source of information, or as the basis for the semiempirical technique of calculation, and in others as a check of the new theoretical procedures. There are several experimental methods of direct determination of the resonance integral: the activation method (1,2), the reactor oscillator and the danger coefficient method. Indirectly, using the results of critical experiments, it is possible to determine correlated values of the effective resonance integral. The present work investigates the dependence of the effective resonance integral on the lattice pitch. Theoretically, the dependence is determined starting from Wigner's rational approximation in which the lattice is characterized by the effective ratio (S/M) {sup X}. Later this allows correlation between the lattice resonance integral and the resonance integral of the single rod (the rod in infinite medium). Using two approximations for Dancoff's factor we give the measured functional dependence of the effective resonance integral on the effective (S/M){sup X} ratio. To determine the resonance integral experimentally we used the activation method and the differential technique of measuring absorption distribution in U{sup 2}38. Since, because of the use of cadmium in determining the cadmium ratio in the fuel rod the effective lattice pitch cannot be defined with certain reliability, besides
Energy Technology Data Exchange (ETDEWEB)
Krcevinac, S; Takac, S [Institute of Nuclear Sciences Boris Kidric, Vinca, Beograd (Yugoslavia)
1966-04-15
The present work investigates the dependence of the effective resonance integral on the lattice pitch. Theoretically, the dependence is determined starting from Wigner's rational approximation in which the lattice is characterized by the effective ratio (s/M). Later this allows correlation between the lattice resonance integral and the resonance integral of the single rod (the rod in infinite medium). Using two approximations for Dancoff's factor we give the measured functional dependence of the effective resonance integral on the effective (s/M) ratio. The activation method and the differential technique of measuring absorption distribution in U-238 are used to determine the resonance integral experimentally. Since the effective lattice pitch cannot be defined with certain reliability, due to the use of cadmium in determining the cadmium ratio in the fuel rod, besides other perturbing effects, the method of comparing thermal activations of U-238 and a suitable thermal detector are used to determine the cadmium ratio.
International Nuclear Information System (INIS)
Krcevinac, S.; Takac, S.
1966-04-01
The present work investigates the dependence of the effective resonance integral on the lattice pitch. Theoretically, the dependence is determined starting from Wigner's rational approximation in which the lattice is characterized by the effective ratio (s/M). Later this allows correlation between the lattice resonance integral and the resonance integral of the single rod (the rod in infinite medium). Using two approximations for Dancoff's factor we give the measured functional dependence of the effective resonance integral on the effective (s/M) ratio. The activation method and the differential technique of measuring absorption distribution in U-238 are used to determine the resonance integral experimentally. Since the effective lattice pitch cannot be defined with certain reliability, due to the use of cadmium in determining the cadmium ratio in the fuel rod, besides other perturbing effects, the method of comparing thermal activations of U-238 and a suitable thermal detector are used to determine the cadmium ratio
The effect of non-uniform fuel rod temperatures on effective resonance integrals
International Nuclear Information System (INIS)
Reichel, A.
1961-06-01
The effective resonance integral for heterogeneous lattices can be reduced to the effective resonance integral for an equivalent homogeneous system with a fairly well defined error depending on lump size and geometry. This report investigates the effect of a radial parabolic temperature variation in cylindrical lumps on the equivalent homogeneous effective resonance integral. Also determined is the equivalent uniform temperature to be taken in the usual formulae to allow for non-uniform fuel rod temperature. This effective temperature is found to be T eff. = T s + 4/9 (T c - T s ) where T s and T c are the surface and central temperatures of the lump. (author)
Multilevel effect in uranium-238 and thorium-232 effective neutron capture resonance integrals
International Nuclear Information System (INIS)
Tellier, H.
1981-01-01
Until now, there has been a discrepancy between the computed and the measured values of the /sup 238/U effective capture integral. Recently, several new measurements of the resonance parameters were carried out and the use of a multilevel formalism was suggested to compute the /sup 238/U cross sections. This paper shows that the simultaneous use of recent parameters and the Reich-Moore formalism explain the discrepancy. 31 refs
Energy Technology Data Exchange (ETDEWEB)
Monteiro, M A.M. [NUCLEN, Rio de Janeiro, RJ (Brazil); Martinez, A S [Universidade Federal, Rio de Janeiro, RJ (Brazil). Coordenacao dos Programas de Pos-graduacao de Engenharia
1990-01-01
It is presented a method for the Resonance Integral Calculation in the fuel and moderator regions, including the shadowing effect. This effect appears due to the presence of several fuel rods in a infinite moderator region. The method is based on the approximations to the J ({xi}, {beta}) function and theirs partial derivatives in relation to {beta}. The dependence of the Resonance Integral in the J ({xi}, {beta}) comes from the rational approximation to the neutron escape probability. The final results were obtained in a very simple and fast way, and they show the good accuracy of the method. (author).
The Resonance Integral of Gold
Energy Technology Data Exchange (ETDEWEB)
Jirlow, K; Johansson, E
1959-04-15
The resonance activation integral of gold has been determined, by means of cadmium ratio measurements of thin foils in a neutron beam. Comparison was made with a 1/v detector, and the neutron spectra were measured with a chopper. The resonance integral, RI, is defined as {integral}{sub 0.5}{sup {infinity}}{sigma}{sub r}(E)dE/E, where {sigma}{sub r}(E) is the differenc between the total absorption cross section and the 1/v part. An experimental value of 1490 {+-} 40 barns has been obtained. RI has also been computed from resonance parameter data with the result 1529 {+-} 70 barns.
Doehrmann, Oliver; Weigelt, Sarah; Altmann, Christian F; Kaiser, Jochen; Naumer, Marcus J
2010-03-03
Information integration across different sensory modalities contributes to object recognition, the generation of associations and long-term memory representations. Here, we used functional magnetic resonance imaging adaptation to investigate the presence of sensory integrative effects at cortical levels as early as nonprimary auditory and extrastriate visual cortices, which are implicated in intermediate stages of object processing. Stimulation consisted of an adapting audiovisual stimulus S(1) and a subsequent stimulus S(2) from the same basic-level category (e.g., cat). The stimuli were carefully balanced with respect to stimulus complexity and semantic congruency and presented in four experimental conditions: (1) the same image and vocalization for S(1) and S(2), (2) the same image and a different vocalization, (3) different images and the same vocalization, or (4) different images and vocalizations. This two-by-two factorial design allowed us to assess the contributions of auditory and visual stimulus repetitions and changes in a statistically orthogonal manner. Responses in visual regions of right fusiform gyrus and right lateral occipital cortex were reduced for repeated visual stimuli (repetition suppression). Surprisingly, left lateral occipital cortex showed stronger responses to repeated auditory stimuli (repetition enhancement). Similarly, auditory regions of interest of the right middle superior temporal gyrus and sulcus exhibited repetition suppression to auditory repetitions and repetition enhancement to visual repetitions. Our findings of crossmodal repetition-related effects in cortices of the respective other sensory modality add to the emerging view that in human subjects sensory integrative mechanisms operate on earlier cortical processing levels than previously assumed.
The Resonance Integral of Niobium
Energy Technology Data Exchange (ETDEWEB)
Hellstrand, E; Lundgren, G
1962-08-15
The resonance integral of niobium has been studied by both pile oscillator and activation techniques. A value of 8.15b {+-} 0.65 b was obtained for the infinitely dilute integral. In addition, the variation of the resonance integral with foil thickness has been measured for thicknesses in the range 0.06 mm to 1.36 mm. A separate study of the half-life of the isomeric state in {sup 94}Nb yielded a value T{sub 1/2} = 6.30 - 0.03 m which is about 5 % lower than the value given in literature.
Resonance integral of cylindrical absorber; Rezonantni integral cilindricnog absorbera
Energy Technology Data Exchange (ETDEWEB)
Slipicevic, K [Elektrotehnicki fakultet, Belgrade (Yugoslavia)
1968-07-01
This paper presents the procedure for calculating effective resonance integral for cylindrical rod which enables derivation of improved spatial distribution of source neutron flux. Application of this new expression for penetration factor, simultaneously with Doppler broadening of Breight-Wigner line enabled derivation of new equation for resonance integral which is valid for the whole range of surface-volume ratio of the rod, has correct boundary conditions and gives as special, results same as Wigner and Pomeranchuk. Functions for correcting the effects of interference of potential and resonance dissipation are derived separately.
Energy Technology Data Exchange (ETDEWEB)
Markovic, V; Kocic, A [Institute of nuclear sciences Boris Kidric, Vinca, Beograd (Yugoslavia)
1965-12-15
Good understanding of the nuclear properties of the materials in the reactor core is essential for reactor operation. One of the fundamental properties is the resonance absorption of the fuel, which is directly included in the reactor calculation through resonance escape probability and influences the choice of the materials quality in the core. This paper describes the measurement of resonance absorption integral of the natural uranium as a function of the S/M ratio. Improved experiment planning and analysis of results, as well as improvement of the ROB-1 reactor oscillator device related to the interpretation of results and decrease of reactor drift variations during measurement enabled higher precision of results compared to previous experiments. Poznavanje osobina nuklearnih karakteristika materijala koji ulaze u jezgro nuklearnog reaktora predstavlja bitan faktor u njegovom rezimu rada. Jedna od osnovnih je svakako rezonantna apsorpcija goriva, cija velicina - preko faktora rezonantnog izbegavanja - direktno ulazi u proracun nuklearnih reaktora i utice na izbor kvaliteta materijala koji ga sacinjavaju. U radu se opisuje merenje rezonantnog apsorpcionog integrala prirodnog urana u funkciji odnosa S/M. Bolja postavka eksperimenta i interpretacija rezultata, s jedne strane, i poboljsanje uredjaja reaktorskog oscilatora ROB-1 /1/ u pogledu analize podataka i smanjenja promene drifta reaktora u toku merenja, s druge strane, daju znacaj ovom radu u pogledu dobijanja preciznijih rezultata u odnosu na ranije /2/ (author)
International Nuclear Information System (INIS)
Hong, Ser Gi; Kim, Kang-Seog
2011-01-01
This paper describes the iteration methods using resonance integral tables to estimate the effective resonance cross sections in heterogeneous transport lattice calculations. Basically, these methods have been devised to reduce an effort to convert resonance integral table into subgroup data to be used in the physical subgroup method. Since these methods do not use subgroup data but only use resonance integral tables directly, these methods do not include an error in converting resonance integral into subgroup data. The effective resonance cross sections are estimated iteratively for each resonance nuclide through the heterogeneous fixed source calculations for the whole problem domain to obtain the background cross sections. These methods have been implemented in the transport lattice code KARMA which uses the method of characteristics (MOC) to solve the transport equation. The computational results show that these iteration methods are quite promising in the practical transport lattice calculations.
An analytical approximation for resonance integral
International Nuclear Information System (INIS)
Magalhaes, C.G. de; Martinez, A.S.
1985-01-01
It is developed a method which allows to obtain an analytical solution for the resonance integral. The problem formulation is completely theoretical and based in concepts of physics of general character. The analytical expression for integral does not involve any empiric correlation or parameter. Results of approximation are compared with pattern values for each individual resonance and for sum of all resonances. (M.C.K.) [pt
Integral data analysis for resonance parameters determination
International Nuclear Information System (INIS)
Larson, N.M.; Leal, L.C.; Derrien, H.
1997-09-01
Neutron time-of-flight experiments have long been used to determine resonance parameters. Those resonance parameters have then been used in calculations of integral quantities such as Maxwellian averages or resonance integrals, and results of those calculations in turn have been used as a criterion for acceptability of the resonance analysis. However, the calculations were inadequate because covariances on the parameter values were not included in the calculations. In this report an effort to correct for that deficiency is documented: (1) the R-matrix analysis code SAMMY has been modified to include integral quantities of importance, (2) directly within the resonance parameter analysis, and (3) to determine the best fit to both differential (microscopic) and integral (macroscopic) data simultaneously. This modification was implemented because it is expected to have an impact on the intermediate-energy range that is important for criticality safety applications
Evaluation of temperature dependent neutron resonance integrals
International Nuclear Information System (INIS)
Menon, S.V.G.; Sahni, D.C.
1975-01-01
The Fourier transform method is extended for evaluating temperature dependent resonance integrals and Doppler coefficients. With the temperature dependent cross-sections, the slowing-down equation is transformed into a Fredholm integral equation of second kind. A method of solution is presented using the familiar Gauss-Hermite quadrature formulae. As a byproduct of the above technique, a fast and accurate method for computing the resonance integral J-function is given. (orig.) [de
Integrated unaligned resonant modulator tuning
Energy Technology Data Exchange (ETDEWEB)
Zortman, William A.; Lentine, Anthony L.
2017-10-03
Methods and systems for tuning a resonant modulator are disclosed. One method includes receiving a carrier signal modulated by the resonant modulator with a stream of data having an approximately equal number of high and low bits, determining an average power of the modulated carrier signal, comparing the average power to a predetermined threshold, and operating a tuning device coupled to the resonant modulator based on the comparison of the average power and the predetermined threshold. One system includes an input structure, a plurality of processing elements, and a digital control element. The input structure is configured to receive, from the resonant modulator, a modulated carrier signal. The plurality of processing elements are configured to determine an average power of the modulated carrier signal. The digital control element is configured to operate a tuning device coupled to the resonant modulator based on the average power of the modulated carrier signal.
International Nuclear Information System (INIS)
Zmijarevic, I.
1980-01-01
Space-energy distribution of resonance neutrons in reactor lattice cell was determined by solving the Boltzmann equation by spherical harmonics method applying P-3 approximation. Computer code SPLET used for these calculations is described. Resonance absorption and calculation of resonance integrals are described as well. Effective resonance integral values for U-238 resonance at 6.7 Ev are calculated for heavy water reactor cell with metal, oxide and carbide fuel elements
Resonance integral calculations for high temperature reactors
International Nuclear Information System (INIS)
Blake, J.P.H.
1960-02-01
Methods of calculation of resonance integrals of finite dilution and temperature are given for both, homogeneous and heterogeneous geometries, together with results obtained from these methods as applied to the design of high temperature reactors. (author)
A discussion of coupling and resonance effects for integrated systems consisting of subsystems
International Nuclear Information System (INIS)
Lin, C.W.; Liu, T.H.
1975-01-01
Three representative cases are studied to evaluate the interaction effect and to establish the need to include both stiffness and mass of the interacting systems in the system model. The first case is a supported system supported by a two-degrees-of-freedom supporting system. The second case represents two single degree of freedom systems, each supported by itself, but interconnected by a spring. The third case is a single degree of freedom system supported by another single degree of freedom supporting system. In each of the three case studied, the interaction effect is first measured by the difference in their natural frequencies for both the coupled system and the uncoupled systems. Although natural frequencies are important to the dynamic analysis of a system, the ultimate decision of whether the mathematical model is realistic depends on the result of the system response it predicts. With this in mind, case three is then studied with a white noise input. It is found that the root mean square response of both the supporting systems are substantially lower when coupled than when the systems are analyzed separately. Based on the results of this study, guidelines are provided for the subdivision into subsystems. (orig./HP) [de
A numerical method for resonance integral calculations
International Nuclear Information System (INIS)
Tanbay, Tayfun; Ozgener, Bilge
2013-01-01
A numerical method has been proposed for resonance integral calculations and a cubic fit based on least squares approximation to compute the optimum Bell factor is given. The numerical method is based on the discretization of the neutron slowing down equation. The scattering integral is approximated by taking into account the location of the upper limit in energy domain. The accuracy of the method has been tested by performing computations of resonance integrals for uranium dioxide isolated rods and comparing the results with empirical values. (orig.)
Multilayer Integrated Film Bulk Acoustic Resonators
Zhang, Yafei
2013-01-01
Multilayer Integrated Film Bulk Acoustic Resonators mainly introduces the theory, design, fabrication technology and application of a recently developed new type of device, multilayer integrated film bulk acoustic resonators, at the micro and nano scale involving microelectronic devices, integrated circuits, optical devices, sensors and actuators, acoustic resonators, micro-nano manufacturing, multilayer integration, device theory and design principles, etc. These devices can work at very high frequencies by using the newly developed theory, design, and fabrication technology of nano and micro devices. Readers in fields of IC, electronic devices, sensors, materials, and films etc. will benefit from this book by learning the detailed fundamentals and potential applications of these advanced devices. Prof. Yafei Zhang is the director of the Ministry of Education’s Key Laboratory for Thin Films and Microfabrication Technology, PRC; Dr. Da Chen was a PhD student in Prof. Yafei Zhang’s research group.
Isotopic effect giant resonances
International Nuclear Information System (INIS)
Buenerd, M.; Lebrun, D.; Martin, P.; Perrin, G.; Saintignon, P. de; Chauvin, J.; Duhamel, G.
1981-10-01
The systematics of the excitation energy of the giant dipole, monopole, and quadrupole resonances are shown to exhibit an isotopic effect. For a given element, the excitation energy of the transition decreases faster with the increasing neutron number than the empirical laws fitting the overall data. This effect is discussed in terms of the available models
Path-integral approach to resonant electron-molecule scattering
International Nuclear Information System (INIS)
Winterstetter, M.; Domcke, W.
1993-01-01
A path-integral formulation of resonant electron-molecule scattering is developed within the framework of the projection-operator formalism of scattering theory. The formation and decay of resonances is treated in real time as a quantum-mechanical electronic-tunneling process, modified by the coupling of the electronic motion with the nuclear degrees of freedom. It is shown that the electronic continuum can be summed over in the path-integral formulation, resulting formally in the path integral for an effective two-state system with coupling to vibrations. The harmonic-oscillator approximation is adopted for the vibrational motion in the present work. Approximation methods are introduced which render the numerical evaluation of the sum over paths feasible for up to ∼10 3 elementary time slices. The theory is numerically realized for simple but nontrivial models representing the 2 Π g d-wave shape resonance in e - +N 2 collisions and the 2 Σ u + p-wave shape resonance in e - +H 2 collisions, respectively. The accuracy of the path-integral results is assessed by comparison with exact numerical reference data for these models. The essential virtue of the path-integral approach is the fact that the computational effort scales at most linearly with the number of vibrational degrees of freedom. The path-integral method is thus well suited to treat electron collisions with polyatomic molecules and molecular aggregates
Nonlinear resonance in Duffing oscillator with fixed and integrative ...
Indian Academy of Sciences (India)
We study the nonlinear resonance, one of the fundamental phenomena in nonlinear oscillators, in a damped and periodically-driven Dufﬁng oscillator with two types of time-delayed feedbacks, namely, ﬁxed and integrative. Particularly, we analyse the effect of the time-delay parameter and the strength of the ...
Nonlinear resonance in Duffing oscillator with fixed and integrative ...
Indian Academy of Sciences (India)
2012-03-02
Mar 2, 2012 ... Abstract. We study the nonlinear resonance, one of the fundamental phenomena in nonlinear oscillators, in a damped and periodically-driven Duffing oscillator with two types of time-delayed feedbacks, namely, fixed and integrative. Particularly, we analyse the effect of the time-delay parameter α and the ...
An attempt to explain the uranium 238 resonance integral discrepancy
International Nuclear Information System (INIS)
Tellier, H.; Grandotto, M.
1978-01-01
Studies on uranium 238 resonance integral discrepancy were carried out for light water reactor physics. It was shown that using recently published resonance parameters and substituting a multilevel formalism to the usual Breit and Wigner formula reduced the well known discrepancy between two values of the uranium 238 effective resonance integral: the value calculated with the nuclear data and the one deduced from critical experiments. Since the cross section computed with these assumptions agrees quite well with the Oak-Ridge transmission data, it was used to obtain the self-shielding effect and the capture rate in light water lattices. The multiplication factor calculated with this method is found very close to the experimental value. Preliminary results for a set of benchmarks relative to several types of thermal neutron reactors lead to very low discrepancies. The reactivity loss is only 130 x 10 -5 instead of 650 x 10 -5 in the case of the usual libraries and the single level formula
The resonance integral of thorium metal rods
Energy Technology Data Exchange (ETDEWEB)
Hellstrand, E; Weitman, J
1960-03-15
The resonance integral for thorium metal rods of different diameters has been determined by the activation method. The irradiations took place in the central channel of the reactor R1, where the energy dependence of the neutron flux had earlier been investigated with a fast chopper up to about 1 keV. The absolute calibration was made with gold as a standard. The true resonance integral for gold was taken from the literature as 1,500 {+-} 35 b. The experimental values for thorium were fitted to two alternative expressions with the following results: RI = (1.70 + 15.9{radical}(S/M)) {+-} 5.5%; RI 17.3{radical}(S/M + 0.06) {+-} 5.5 %. The measurements were made for S/M values in the range 0.14 - 0.87 cm{sup 2}/g. The main contribution to the margin of errors arises from the uncertainties in the cross sections used and in the correction for the departure of the neutron energy distribution from the 1/E form.
Proportional-Integral-Resonant AC Current Controller
Directory of Open Access Journals (Sweden)
STOJIC, D.
2017-02-01
Full Text Available In this paper an improved stationary-frame AC current controller based on the proportional-integral-resonant control action (PIR is proposed. Namely, the novel two-parameter PIR controller is applied in the stationary-frame AC current control, accompanied by the corresponding parameter-tuning procedure. In this way, the proportional-resonant (PR controller, common in the stationary-frame AC current control, is extended by the integral (I action in order to enable the AC current DC component tracking, and, also, to enable the DC disturbance compensation, caused by the voltage source inverter (VSI nonidealities and by nonlinear loads. The proposed controller parameter-tuning procedure is based on the three-phase back-EMF-type load, which corresponds to a wide range of AC power converter applications, such as AC motor drives, uninterruptible power supplies, and active filters. While the PIR controllers commonly have three parameters, the novel controller has two. Also, the provided parameter-tuning procedure needs only one parameter to be tuned in relation to the load and power converter model parameters, since the second controller parameter is directly derived from the required controller bandwidth value. The dynamic performance of the proposed controller is verified by means of simulation and experimental runs.
Integrating out resonances in strongly-coupled electroweak scenarios
Directory of Open Access Journals (Sweden)
Rosell Ignasi
2017-01-01
Full Text Available Accepting that there is a mass gap above the electroweak scale, the Electroweak Effective Theory (EWET is an appropriate tool to describe this situation. Since the EWET couplings contain information on the unknown high-energy dynamics, we consider a generic strongly-coupled scenario of electroweak symmetry breaking, where the known particle fields are coupled to heavier states. Then, and by integrating out these heavy fields, we study the tracks of the lightest resonances into the couplings. The determination of the low-energy couplings (LECs in terms of resonance parameters can be made more precise by considering a proper short-distance behaviour on the Lagrangian with heavy states, since the number of resonance couplings is then reduced. Notice that we adopt a generic non-linear realization of the electroweak symmetry breaking with a singlet Higgs.
Calculation of resonance integral for fuel cluster
International Nuclear Information System (INIS)
Remsak, S.
1969-01-01
The procedure for calculating the shielding correction, formulated in the previous paper [6], was broadened and applied for a cluster of cylindrical rods. The sam analytical method as in the previous paper was applied. A combination of Gauss method with the method of Almgren and Porn used for solving the same type of integral was used to calculate the geometry functions. CLUSTER code was written for ZUSE-Z-23 computer to calculate the shielding corrections for pairs of fuel rods in the cluster. Computing time for one pair of fuel rods depends on the number of closely placed rod, and for two closely placed rods it is about 3 hours. Calculations were done for clusters containing 7 and 19 UO 2 rods. results show that calculated values of resonance integrals are somewhat higher than the values obtained by Helstrand empirical formula. Taking into account the results for two rods from the previous paper it can be noted that the calculated and empirical values for clusters with 2 and 7 rods are in agreement since the deviations do not exceed the limits of experimental error (±2%). In case of larger cluster with 19 rods deviations are higher than the experimental error. Most probably the calculated values exceed the experimental ones result from the fact that in this paper the shielding correction is calculated only in the region up to 1 keV [sr
Interference scattering effects on intermediate resonance absorption at operating temperatures
International Nuclear Information System (INIS)
Goldstein, R.
1975-01-01
Resonance integrals may be accurately calculated using the intermediate resonance (IR) approximation. Results are summarized for the case of an absorber with given potential scattering cross sections and interference scattering parameter admixed with a non absorbing moderator of given cross section and located in a narrow resonance moderating medium. From the form of the IR solutions, it is possible to make some general observations about effects of interference scattering on resonance absorption. 2 figures
Integrated polymer micro-ring resonators for optical sensing applications
Girault , Pauline; Lorrain , Nathalie; Poffo , Luiz; Guendouz , Mohammed; Lemaitre , Jonathan; Carré , Christiane; Gadonna , Michel; Bosc , Dominique; Vignaud , Guillaume
2015-01-01
International audience; Micro-resonators (MR) have become a key element for integrated optical sensors due to their integration capability and their easy fabrication with low cost polymer materials. Nowadays, there is a growing need on MRs as highly sensitive and selective functions especially in the areas of food and health. The context of this work is to implement and study integrated micro-ring resonators devoted to sensing applications. They are fabricated by processing SU8 polymer as cor...
Influence of resonance parameters' correlations on the resonance integral uncertainty; 55Mn case
International Nuclear Information System (INIS)
Zerovnik, Gasper; Trkov, Andrej; Capote, Roberto; Rochman, Dimitri
2011-01-01
For nuclides with a large number of resonances the covariance matrix of resonance parameters can become very large and expensive to process in terms of the computation time. By converting covariance matrix of resonance parameters into covariance matrices of background cross-section in a more or less coarse group structure a considerable amount of computer time and memory can be saved. The question is how important is the information that is discarded in the process. First, the uncertainty of the 55 Mn resonance integral was estimated in narrow resonance approximation for different levels of self-shielding using Bondarenko method by random sampling of resonance parameters according to their covariance matrices from two different 55 Mn evaluations: one from Nuclear Research and Consultancy Group NRG (with large uncertainties but no correlations between resonances), the other from Oak Ridge National Laboratory (with smaller uncertainties but full covariance matrix). We have found out that if all (or at least significant part of the) resonance parameters are correlated, the resonance integral uncertainty greatly depends on the level of self-shielding. Second, it was shown that the commonly used 640-group SAND-II representation cannot describe the increase of the resonance integral uncertainty. A much finer energy mesh for the background covariance matrix would have to be used to take the resonance structure into account explicitly, but then the objective of a more compact data representation is lost.
Fabrication of resonant micro cantilevers with integrated transparent fluidic channel
DEFF Research Database (Denmark)
Khan, Faheem; Schmid, Silvan; Davis, Zachary James
2011-01-01
Microfabricated cantilevers are proving their potential as excellent tools for analysis applications. In this paper, we describe the design, fabrication and testing of resonant micro cantilevers with integrated transparent fluidic channels. The cantilevers have been devised to measure the density...
Set up of a method for the adjustment of resonance parameters on integral experiments
International Nuclear Information System (INIS)
Blaise, P.
1996-01-01
Resonance parameters for actinides play a significant role in the neutronic characteristics of all reactor types. All the major integral parameters strongly depend on the nuclear data of the isotopes in the resonance-energy regions.The author sets up a method for the adjustment of resonance parameters taking into account the self-shielding effects and restricting the cross section deconvolution problem to a limited energy region. (N.T.)
Integrated MEMS/NEMS Resonant Cantilevers for Ultrasensitive Biological Detection
Directory of Open Access Journals (Sweden)
Xinxin Li
2009-01-01
Full Text Available The paper reviews the recent researches implemented in Chinese Academy of Sciences, with achievements on integrated resonant microcantilever sensors. In the resonant cantilevers, the self-sensing elements and resonance exciting elements are both top-down integrated with silicon micromachining techniques. Quite a lot of effort is focused on optimization of the resonance mode and sensing structure for improvement of sensitivity. On the other hand, to enable the micro-cantilevers specifically sensitive to bio/chemical molecules, sensing materials are developed and modified on the cantilever surface with a self-assembled monolayer (SAM based bottom-up construction and surface functionalization. To improve the selectivity of the sensors and depress environmental noise, multiple and localized surface modifications are developed. The achieved volume production capability and satisfactory detecting resolution to trace-level biological antigen of alpha-fetoprotein (AFP give the micro-cantilever sensors a great promise for rapid and high-resoluble detection.
Analysis and Modeling of Integrated Magnetics for LLC resonant Converters
DEFF Research Database (Denmark)
Li, Mingxiao; Ouyang, Ziwei; Zhao, Bin
2017-01-01
Shunt-inserted transformers are widely used toobtain high leakage inductance. This paper investigates thismethod in depth to make it applicable to integrate resonantinductor for the LLC resonant converters. The analysis andmodel of magnetizing inductance and leakage inductance forshunt...... transformers can provide a significantdifference. The way to obtain the desirable magnetizing andleakage inductance value for LLC resonant converters issimplified by the creation of air gaps together with a magneticshunt. The calculation and relation are validated by finiteelement analysis (FEA) simulations...
Integrated Microfluidic Sensor System with Magnetostrictive Resonators
Liang, Cai; Kosel, Jü rgen; Gooneratne, Chinthaka
2011-01-01
The present embodiments describe a method that integrates a magnetostrictive sensor with driving and detecting elements into a microfluidic chip to detect a chemical, biochemical or biomedical species. These embodiments may also measure the properties of a fluid such as viscosity, pH values. The whole system can be referred to lab-on-a-chip (LOC) or micro-total-analysis-systems (.mu.TAS). In particular, this present embodiments include three units, including a microfluidics unit, a magnetostrictive sensor, and driving/detecting elements. An analyzer may also be provided to analyze an electrical signal associated with a feature of a target specimen.
Integrated Microfluidic Sensor System with Magnetostrictive Resonators
Liang, Cai
2011-12-08
The present embodiments describe a method that integrates a magnetostrictive sensor with driving and detecting elements into a microfluidic chip to detect a chemical, biochemical or biomedical species. These embodiments may also measure the properties of a fluid such as viscosity, pH values. The whole system can be referred to lab-on-a-chip (LOC) or micro-total-analysis-systems (.mu.TAS). In particular, this present embodiments include three units, including a microfluidics unit, a magnetostrictive sensor, and driving/detecting elements. An analyzer may also be provided to analyze an electrical signal associated with a feature of a target specimen.
Photonic crystal resonator integrated in a microfluidic system
DEFF Research Database (Denmark)
Rodrigues de Sousa Nunes, Pedro André; Mortensen, Niels Asger; Kutter, Jörg Peter
2008-01-01
We report on a novel optofluidic system consisting of a silica-based 1D photonic crystal, integrated planar waveguides, and electrically insulated fluidic channels. An array of pillars in a microfluidic channel designed for electrochromatography is used as a resonator for on-column label...
Relativistic effects in resonance absorption
International Nuclear Information System (INIS)
Drake, J.F.; Lee, Y.C.
1976-01-01
The role of the relativistic-electron-mass variation in the generation of plasma waves by the linear mode conversion of intense electromagnetic waves is investigated. The increase in the electron mass in high intensity regions of the mode-converted wave reduces the local plasma frequency and thereby strongly modifies the plasma-driver resonance. A spatial discontinuity in the structure of the mode-converted wave results and causes the wave to break. Under rather modest restrictions, the wave breaking resulting from these effects occurs before the wave amplitude is limited either by thermal convection or by breaking caused by previously investigated nonrelativistic effects. Consequently, the amplitude of the mode-converted plasma wave should saturate at a much lower level than previously predicted. For simplicity, the analysis is limited to the initial stages of mode conversion where the ion dynamics can be neglected. The validity of this approximation is discussed
Sound Transmission Loss Through a Corrugated-Core Sandwich Panel with Integrated Acoustic Resonators
Schiller, Noah H.; Allen, Albert R.; Zalewski, Bart F; Beck, Benjamin S.
2014-01-01
The goal of this study is to better understand the effect of structurally integrated resonators on the transmission loss of a sandwich panel. The sandwich panel has facesheets over a corrugated core, which creates long aligned chambers that run parallel to the facesheets. When ports are introduced through the facesheet, the long chambers within the core can be used as low-frequency acoustic resonators. By integrating the resonators within the structure they contribute to the static load bearing capability of the panel while also attenuating noise. An analytical model of a panel with embedded resonators is derived and compared with numerical simulations. Predictions show that acoustic resonators can significantly improve the transmission loss of the sandwich panel around the natural frequency of the resonators. In one configuration with 0.813 m long internal chambers, the diffuse field transmission loss is improved by more than 22 dB around 104 Hz. The benefit is achieved with no added mass or volume relative to the baseline structure. The embedded resonators are effective because they radiate sound out-of-phase with the structure. This results in destructive interference, which leads to less transmitted sound power.
The effect of asymmetry on resonant tunneling
International Nuclear Information System (INIS)
Garcia-Calderon, G.
1986-07-01
Resonant tunneling experiments on multibarrier coupled heterostructures probe the quasistationary nature of the states of the corresponding one dimensional potential. This work considers the effect of asymmetric one dimensional multibarrier potentials on resonant tunneling. It is shown, by using the properties of the propagator of the system, that this effect may lead to novel resonance phenomena and affects the lifetime of the quasistationary states of the system. The above considerations are illustrated by a simple analytical solvable model. (author)
Electronically Tunable Fully Integrated Fractional-Order Resonator
Tsirimokou, Georgia
2017-03-20
A fully integrated implementation of a parallel fractional-order resonator which employs together a fractional order capacitor and a fractional-order inductor is proposed in this paper. The design utilizes current-controlled Operational Transconductance Amplifiers as building blocks, designed and fabricated in AMS 0:35m CMOS process, and based on a second-order approximation of a fractional-order differentiator/ integrator magnitude optimized in the range 10Hz–700Hz. An attractive benefit of the proposed scheme is its electronic tuning capability.
Electronically Tunable Fully Integrated Fractional-Order Resonator
Tsirimokou, Georgia; Psychalinos, Costas; Elwakil, Ahmed S.; Salama, Khaled N.
2017-01-01
A fully integrated implementation of a parallel fractional-order resonator which employs together a fractional order capacitor and a fractional-order inductor is proposed in this paper. The design utilizes current-controlled Operational Transconductance Amplifiers as building blocks, designed and fabricated in AMS 0:35m CMOS process, and based on a second-order approximation of a fractional-order differentiator/ integrator magnitude optimized in the range 10Hz–700Hz. An attractive benefit of the proposed scheme is its electronic tuning capability.
Diamond electro-optomechanical resonators integrated in nanophotonic circuits
Energy Technology Data Exchange (ETDEWEB)
Rath, P.; Ummethala, S.; Pernice, W. H. P., E-mail: wolfram.pernice@kit.edu [Institute of Nanotechnology, Karlsruhe Institute of Technology, 76344 Eggenstein-Leopoldshafen (Germany); Diewald, S. [Center for Functional Nanostructures, Karlsruhe Institute of Technology, 76131 Karlsruhe (Germany); Lewes-Malandrakis, G.; Brink, D.; Heidrich, N.; Nebel, C. [Fraunhofer Institute for Applied Solid State Physics, Tullastr. 72, 79108 Freiburg (Germany)
2014-12-22
Diamond integrated photonic devices are promising candidates for emerging applications in nanophotonics and quantum optics. Here, we demonstrate active modulation of diamond nanophotonic circuits by exploiting mechanical degrees of freedom in free-standing diamond electro-optomechanical resonators. We obtain high quality factors up to 9600, allowing us to read out the driven nanomechanical response with integrated optical interferometers with high sensitivity. We are able to excite higher order mechanical modes up to 115 MHz and observe the nanomechanical response also under ambient conditions.
Integrated polymer micro-ring resonators for optical sensing applications
Girault, Pauline; Lorrain, Nathalie; Poffo, Luiz; Guendouz, Mohammed; Lemaitre, Jonathan; Carré, Christiane; Gadonna, Michel; Bosc, Dominique; Vignaud, Guillaume
2015-03-01
Micro-resonators (MR) have become a key element for integrated optical sensors due to their integration capability and their easy fabrication with low cost polymer materials. Nowadays, there is a growing need on MRs as highly sensitive and selective functions especially in the areas of food and health. The context of this work is to implement and study integrated micro-ring resonators devoted to sensing applications. They are fabricated by processing SU8 polymer as core layer and PMATRIFE polymer as lower cladding layer. The refractive index of the polymers and of the waveguide structure as a function of the wavelength is presented. Using these results, a theoretical study of the coupling between ring and straight waveguides has been undertaken in order to define the MR design. Sub-micronic gaps of 0.5 μm to 1 μm between the ring and the straight waveguides have been successfully achieved with UV (i-lines) photolithography. Different superstrates such as air, water, and aqueous solutions with glucose at different concentrations have been studied. First results show a good normalized transmission contrast of 0.98, a resonator quality factor around 1.5 × 104 corresponding to a coupling ratio of 14.7%, and ring propagation losses around 5 dB/cm. Preliminary sensing experiments have been performed for different concentrations of glucose; a sensitivity of 115 ± 8 nm/RIU at 1550 nm has been obtained with this couple of polymers.
International Nuclear Information System (INIS)
Story, J.S.
1969-09-01
The data available up to the end of November 1968 on the thermal neutron absorption cross-sections, resonance absorption integrals, and resonance parameters of silicon and its stable isotopes are collected and discussed. Estimates are given of the mean spacing of the energy levels of the compound nuclei near the neutron binding energy. It is concluded that the thermal neutron absorption cross-section and resonance absorption integral of natural silicon are not well established. The data on these two parameters are somewhat correlated, and three different assessments of the resonance integral are presented which differ over-all by a factor of 230. Many resonances have been detected by charged particle reactions which have not yet been observed in neutron cross-section measurements. One of these resonances of Si 2 8, at E n = 4 ± 5 keV might account for the large resonance integral which is derived, very uncertainly, from integral data. The principal source of the measured resonance integral of Si 3 0 has not yet been located. The thermal neutron absorption cross-section of Si 2 8 appears to result mainly from a negative energy resonance, possibly the resonance at E n = - 59 ± 5 keV detected by the Si 2 8 (d,p) reaction. (author)
Memory effects on stochastic resonance
Neiman, Alexander; Sung, Wokyung
1996-02-01
We study the phenomenon of stochastic resonance (SR) in a bistable system with internal colored noise. In this situation the system possesses time-dependent memory friction connected with noise via the fluctuation-dissipation theorem, so that in the absence of periodic driving the system approaches the thermodynamic equilibrium state. For this non-Markovian case we find that memory usually suppresses stochastic resonance. However, for a large memory time SR can be enhanced by the memory.
Space charge effects: tune shifts and resonances
International Nuclear Information System (INIS)
Weng, W.T.
1986-08-01
The effects of space charge and beam-beam interactions on single particle motion in the transverse degree of freedom are considered. The space charge force and the resulting incoherent tune shift are described, and examples are given from the AGS and CERN's PSB. Equations of motion are given for resonances in the presence of the space charge force, and particle behavior is examined under resonance and space charge conditions. Resonance phase space structure is described with and without space charge. Uniform and bunched beams are compared. Beam-beam forces and resonances and beam-beam detuning are described. 18 refs., 15 figs
Coupling thermal atomic vapor to an integrated ring resonator
International Nuclear Information System (INIS)
Ritter, R; Kübler, H; Pfau, T; Löw, R; Gruhler, N; Pernice, W H P
2016-01-01
Strongly interacting atom–cavity systems within a network with many nodes constitute a possible realization for a quantum internet which allows for quantum communication and computation on the same platform. To implement such large-scale quantum networks, nanophotonic resonators are promising candidates because they can be scalably fabricated and interconnected with waveguides and optical fibers. By integrating arrays of ring resonators into a vapor cell we show that thermal rubidium atoms above room temperature can be coupled to photonic cavities as building blocks for chip-scale hybrid circuits. Although strong coupling is not yet achieved in this first realization, our approach provides a key step towards miniaturization and scalability of atom–cavity systems. (paper)
measurements of the absorption resonance integrals by reactor oscillator method
International Nuclear Information System (INIS)
Markovic, V.; Kocic, A.
1965-12-01
Experimental values of resonance integrals for silver vary significantly dependent on authors. That is why we have chosen this sample to measure RI. On the other hand, nuclear fuel (for example natural uranium) still represents an interesting objective for research in reactor physics. Measurements of natural uranium are done as a function of S/M. Measurements were done by amplitude reactor oscillator ROB-1/5 with precision from 0.5% - 2% dependent on the conditions of the oscillator. Measurements were completed at the heavy water reactor RB with 2% enriched uranium fuel [fr
Ultrasonic series resonant converter with integrated L-C-T
CSIR Research Space (South Africa)
Smit, MC
1995-01-01
Full Text Available primary plate separation, w G bifilar primary 2EOE,NpW(h + To - T;) d C= where d plate width. Fig. 8. SPICE model of discrete component converter ~ 21 B. Spice Simulation The objective of the simulation is to show that the integrated structure... reacts in the same way as a discrete series inductor capacitor and transformer would do, and in turn agrees with the experimental results. Fig. 8 shows the SPICE circuit model of the discrete component series resonant converter. Inductance L...
International Nuclear Information System (INIS)
Haeggblom, H.
1968-08-01
The method of calculating the resonance interaction effect by series expansions has been studied. Starting from the assumption that the neutron flux in a homogeneous mixture is inversely proportional to the total cross section, the expression for the flux can be simplified by series expansions. Two types of expansions are investigated and it is shown that only one of them is generally applicable. It is also shown that this expansion gives sufficient accuracy if the approximate resonance line shape function is reasonably representative. An investigation is made of the approximation of the resonance shape function with a Gaussian function which in some cases has been used to calculate the interaction effect. It is shown that this approximation is not sufficiently accurate in all cases which can occur in practice. Then, a rational approximation is introduced which in the first order approximation gives the same order of accuracy as a practically exact shape function. The integrations can be made analytically in the complex plane and the method is therefore very fast compared to purely numerical integrations. The method can be applied both to statistically correlated and uncorrelated resonances
Energy Technology Data Exchange (ETDEWEB)
Haeggblom, H
1968-08-15
The method of calculating the resonance interaction effect by series expansions has been studied. Starting from the assumption that the neutron flux in a homogeneous mixture is inversely proportional to the total cross section, the expression for the flux can be simplified by series expansions. Two types of expansions are investigated and it is shown that only one of them is generally applicable. It is also shown that this expansion gives sufficient accuracy if the approximate resonance line shape function is reasonably representative. An investigation is made of the approximation of the resonance shape function with a Gaussian function which in some cases has been used to calculate the interaction effect. It is shown that this approximation is not sufficiently accurate in all cases which can occur in practice. Then, a rational approximation is introduced which in the first order approximation gives the same order of accuracy as a practically exact shape function. The integrations can be made analytically in the complex plane and the method is therefore very fast compared to purely numerical integrations. The method can be applied both to statistically correlated and uncorrelated resonances.
Wireless passive polymer-derived SiCN ceramic sensor with integrated resonator/antenna
Li, Yan; Yu, Yuxi; San, Haisheng; Wang, Yansong; An, Linan
2013-10-01
This paper presents a passive wireless polymer-derived silicon carbonitride (SiCN) ceramic sensor based on cavity radio frequency resonator together with integrated slot antenna. The effect of the cavity sensor dimensions on the Q-factor and resonant frequency is investigated by numerical simulation. A sensor with optimal dimensions is designed and fabricated. It is demonstrated that the sensor signal can be wirelessly detected at distances up to 20 mm. Given the high-temperature stability of the SiCN, the sensor is very promising for high-temperature wireless sensing applications.
Integrated refractive index optical ring resonator detector for capillary electrophoresis.
Zhu, Hongying; White, Ian M; Suter, Jonathan D; Zourob, Mohammed; Fan, Xudong
2007-02-01
We developed a novel miniaturized and multiplexed, on-capillary, refractive index (RI) detector using liquid core optical ring resonators (LCORRs) for future development of capillary electrophoresis (CE) devices. The LCORR employs a glass capillary with a diameter of approximately 100 mum and a wall thickness of a few micrometers. The circular cross section of the capillary forms a ring resonator along which the light circulates in the form of the whispering gallery modes (WGMs). The WGM has an evanescent field extending into the capillary core and responds to the RI change due to the analyte conducted in the capillary, thus permitting label-free measurement. The resonating nature of the WGM enables repetitive light-analyte interaction, significantly enhancing the LCORR sensitivity. This LCORR architecture achieves dual use of the capillary as a sensor head and a CE fluidic channel, allowing for integrated, multiplexed, and noninvasive on-capillary detection at any location along the capillary. In this work, we used electro-osmotic flow and glycerol as a model system to demonstrate the fluid transport capability of the LCORRs. In addition, we performed flow speed measurement on the LCORR to demonstrate its flow analysis capability. Finally, using the LCORR's label-free sensing mechanism, we accurately deduced the analyte concentration in real time at a given point on the capillary. A sensitivity of 20 nm/RIU (refractive index units) was observed, leading to an RI detection limit of 10-6 RIU. The LCORR marries photonic technology with microfluidics and enables rapid on-capillary sample analysis and flow profile monitoring. The investigation in this regard will open a door to novel high-throughput CE devices and lab-on-a-chip sensors in the future.
Analog implementation of an integral resonant control scheme
International Nuclear Information System (INIS)
Pereira, E; Moheimani, S O R; Aphale, S S
2008-01-01
Integral resonant control (IRC) has been introduced as a high performance controller design methodology for flexible structures with collocated actuator–sensor pairs. IRC has a simple structure and is capable of achieving significant damping, over several modes, while guaranteeing closed-loop stability of the system in the presence of unmodeled out-of-bandwidth dynamics. IRC can be an ideal controller for various industrial damping applications, if packaged in a simple easy-to-implement electronic module. This work proposes an analog implementation of the IRC scheme using a single Op-Amp circuit. The objective is to show that with simple analog realization of the modified IRC scheme, it is possible to damp a large number of vibration modes. A brief discussion about the modeling, circuit considerations, implementation and experimental results is presented in order to validate the usefulness and practicality of the proposed analog IRC implementation. (technical note)
Effect of couplings in the resonance continuum
International Nuclear Information System (INIS)
Royal, J; Larson, A; Orel, A E
2004-01-01
Electronic coupling of two or more resonances via the electron scattering continuum is investigated. The effect of this coupling as a function of the resonance curves and autoionization widths is investigated, and the conditions for the maximum effect are determined. The theory is applied to two physical problems, the product state distribution produced by the dissociative recombination of electrons with HeH + and a one-dimensional model for ion-pair production resulting from electron collisions with H + 3 . It is found that the coupling does not affect the product state distribution in HeH + but produces a significant effect in the H + 3 model
Issues of effective field theories with resonances
International Nuclear Information System (INIS)
Gegelia, J.; Japaridze, G.
2014-01-01
We address some issues of renormalization and symmetries of effective field theories with unstable particles - resonances. We also calculate anomalous contributions in the divergence of the singlet axial current in an effective field theory of massive SU(N) Yang-Mills fields interacting with fermions and discuss their possible relevance to the strong CP problem. (author)
Nonlinear effects in varactor-tuned resonators.
Everard, Jeremy; Zhou, Liang
2006-05-01
This paper describes the effects of RF power level on the performance of varactor-tuned resonator circuits. A variety of topologies are considered, including series and parallel resonators operating in both unbalanced and balanced modes. As these resonators were designed to produce oscillators with minimum phase noise, the initial small signal insertion loss was set to 6 dB and, hence, QL/Q0 = 1/2. To enable accurate analysis and simulation, S parameter and PSPICE models for the varactors were optimized and developed. It is shown that these resonators start to demonstrate nonlinear operation at very low power levels demonstrating saturation and lowering of the resonant frequency. On occasion squegging is observed for modified bias conditions. The nonlinear effects are dependent on the unloaded Q (Q0), the ratio of loaded to unloaded Q (QL/Q0), the bias voltage, and circuit configurations with typical nonlinear effects occurring at -8 dBm in a circuit with a loaded Q of 63 and a varactor bias voltage of 3 V. Analysis, simulation, and measurements that show close correlation are presented.
Integrated variable projection approach (IVAPA) for parallel magnetic resonance imaging.
Zhang, Qiao; Sheng, Jinhua
2012-10-01
Parallel magnetic resonance imaging (pMRI) is a fast method which requires algorithms for the reconstructing image from a small number of measured k-space lines. The accurate estimation of the coil sensitivity functions is still a challenging problem in parallel imaging. The joint estimation of the coil sensitivity functions and the desired image has recently been proposed to improve the situation by iteratively optimizing both the coil sensitivity functions and the image reconstruction. It regards both the coil sensitivities and the desired images as unknowns to be solved for jointly. In this paper, we propose an integrated variable projection approach (IVAPA) for pMRI, which integrates two individual processing steps (coil sensitivity estimation and image reconstruction) into a single processing step to improve the accuracy of the coil sensitivity estimation using the variable projection approach. The method is demonstrated to be able to give an optimal solution with considerably reduced artifacts for high reduction factors and a low number of auto-calibration signal (ACS) lines, and our implementation has a fast convergence rate. The performance of the proposed method is evaluated using a set of in vivo experiment data. Copyright © 2012 Elsevier Ltd. All rights reserved.
TUZ, Resonance Integrals in Unresolved Region, Various Temperature, From Porter-Thomas Distribution
International Nuclear Information System (INIS)
Kuncir, G.F.
1969-01-01
1 - Nature of physical problem solved: TUZ computes resonance integrals for a wide variety of temperatures, compositions, and geometries for the unresolved resonances. 2 - Method of solution: The resonances are considered to be defined by an average over the Porter-Thomas distribution of neutron widths
Vacuum Gap Microstrip Microwave Resonators for 2.5-D Integration in Quantum Computing
International Nuclear Information System (INIS)
Lewis, Rupert M.; Henry, Michael David; Schroeder, Katlin
2017-01-01
We demonstrate vacuum gap λ/2 microwave resonators as a route toward higher integration in superconducting qubit circuits. The resonators are fabricated from pieces on two silicon chips bonded together with an In-Sb bond. Measurements of the devices yield resonant frequencies in good agreement with simulations. Furthermore, we discuss creating low loss circuits in this geometry.
Towards a fully integrated optical gyroscope using whispering gallery modes resonators
Amrane, T.; Jager, J.-B.; Jager, T.; Calvo, V.; Léger, J.-M.
2017-11-01
Since the developments of lasers and the optical fibers in the 70s, the optical gyroscopes have been subject to an intensive research to improve both their resolution and stability performances. However the best optical gyroscopes currently on the market, the ring laser gyroscope and the interferometer fiber optic gyroscope are still macroscopic devices and cannot address specific applications where size and weight constraints are critical. One solution to overcome these limitations could be to use an integrated resonator as a sensitive part to build a fully Integrated Optical Resonant Gyroscope (IORG). To keep a high rotation sensitivity, which is usually degraded when downsizing this kind of optical sensors based on the Sagnac effect, the resonator has to exhibit a very high quality factor (Q): as detailed in equation (1) where the minimum rotation rate resolution for an IORG is given as a function of the resonator characteristics (Q and diameter D) and of the global system optical system characteristics (i.e. SNR and bandwidth B), the higher the Q×D product, the lower the resolution.
New methodology for analytical calculation of resonance integrals in an heterogeneous medium
International Nuclear Information System (INIS)
Campos, T.P.R. de; Martinez, A.S.
1986-01-01
A new methodology for analytical calculation of Resonance Integral in a typical fuel cell is presented. The expression obtained for the Resonance Integral presents the advantage of being analytical. Its constituent terms are combinations of the well known function J(xi,β) with its partial derivatives in regard to β. This is a general expression for all types of resonance. The parameters used in this method depend on the resonance type and are obtained as a function of the parameter lambda. A simple expression, depending on resonance parameters is proposed for this variable. (Author) [pt
Flexible optical network components based on densely integrated microring resonators
Geuzebroek, D.H.
2005-01-01
This thesis addresses the design, realization and characterization of reconfigurable optical network components based on multiple microring resonators. Since thermally tunable microring resonators can be used as wavelength selective space switches, very compact devices with high complexity and
ZUT, Resonance Integrals in Resolved Region at Various Temperature, Escape Probability Calculation
International Nuclear Information System (INIS)
Kuncir, G.F.
1984-01-01
1 - Nature of physical problem solved: ZUT computes resonance integrals from resonance parameters for a wide variety of temperatures, compositions, and geometries for the resolved resonances. 2 - Method of solution: The form used permits specification of escape probability as a function of the lump dimension and the mean free path. The absorber term may be treated by the integral method, the narrow resonance or the infinite mass approximation. Moderator terms may be represented either by the full integral method (IM) or the asymptotic (NR) form
Integrated optics ring-resonator chemical sensor with polymer transduction layer
Ksendzov, A.; Homer, M. L.; Manfreda, A. M.
2004-01-01
An integrated optics chemical sensor based on a ring resonator with an ethyl cellulose polymer coating has been demonstrated. The measured sensitivity to isopropanol in air is 50 ppm-the level immediately useful for health-related air quality monitoring. The resonator was fabricated using SiO2 and SixNy materials. The signal readout is based on tracking the wavelength of a resonance peak. The resonator layout optimisation for sensing applications is discussed.
Dynamic nonlinear thermal optical effects in coupled ring resonators
Directory of Open Access Journals (Sweden)
Chenguang Huang
2012-09-01
Full Text Available We investigate the dynamic nonlinear thermal optical effects in a photonic system of two coupled ring resonators. A bus waveguide is used to couple light in and out of one of the coupled resonators. Based on the coupling from the bus to the resonator, the coupling between the resonators and the intrinsic loss of each individual resonator, the system transmission spectrum can be classified by three different categories: coupled-resonator-induced absorption, coupled-resonator-induced transparency and over coupled resonance splitting. Dynamic thermal optical effects due to linear absorption have been analyzed for each category as a function of the input power. The heat power in each resonator determines the thermal dynamics in this coupled resonator system. Multiple “shark fins” and power competition between resonators can be foreseen. Also, the nonlinear absorption induced thermal effects have been discussed.
International Nuclear Information System (INIS)
Yu Haitao; Li Xinxin; Gan Xiaohua; Liu Yongjing; Liu Xiang; Xu Pengcheng; Li Jungang; Liu Min
2009-01-01
With an integrated resonance exciting heater and a self-sensing piezoresistor, resonant micro-cantilever bio/chemical sensors are optimally designed and fabricated by micromachining techniques. This study is emphasized on the optimization of the integrated heating resistor. Previous research has put the heater at either the cantilever clamp end, the midpoint or the free end. Aiming at sufficiently high and stable resonant amplitude, our research indicates that the optimized location of the thermal-electric exciting resistor is the clamp end instead of other positions. By both theoretical analysis and resonance experiments where three heating resistors are placed at the three locations of the fabricated cantilever, it is clarified that the clamp end heating provides the most efficient resonance excitation in terms of resonant amplitude, Q-factor and resonance stability. Besides, the optimized combination of dc bias and ac voltage is determined by both analysis and experimental verification. With the optimized heating excitation, the resonant cantilever is used for biotin–avidin-specific detection, resulting in a ±0.1 Hz ultra-low noise floor of the frequency signal and a 130 fg mass resolution. In addition to resonance excitation, the heater is used to heat up the cantilever for speed-up desorption after detection that helps rapid and repeated sensing to chemical vapor. The clamp end is determined (by simulation) as the optimal heating location for uniform temperature distribution on the cantilever. Using the resonant cantilever, a rapid and repeated sensing experiment on dimethyl methylphosphonate (DMMP) vapor shows that a short-period heating at the detection interval significantly quickens the signal recovery and enhances the sensing repeatability
Thermal neutron capture and resonance integral cross sections of {sup 45}Sc
Energy Technology Data Exchange (ETDEWEB)
Van Do, Nguyen; Duc Khue, Pham; Tien Thanh, Kim [Institute of Physics, Vietnam Academy of Science and Technology, 10 Dao Tan, Hanoi (Viet Nam); Thi Hien, Nguyen [Institute of Physics, Vietnam Academy of Science and Technology, 10 Dao Tan, Hanoi (Viet Nam); Department of Physics and Center for High Energy Physics, Kyungpook National University, Daegu 702-701 (Korea, Republic of); Kim, Guinyun, E-mail: gnkim@knu.ac.kr [Department of Physics and Center for High Energy Physics, Kyungpook National University, Daegu 702-701 (Korea, Republic of); Kim, Kwangsoo [Department of Physics and Center for High Energy Physics, Kyungpook National University, Daegu 702-701 (Korea, Republic of); Shin, Sung-Gyun; Cho, Moo-Hyun [Department of Advanced Nuclear Engineering, Pohang University of Science and Technology, Pohang 790-784 (Korea, Republic of); Lee, Manwoo [Research Center, Dongnam Institute of Radiological and Medical Science, Busan 619-953 (Korea, Republic of)
2015-11-01
The thermal neutron cross section (σ{sub 0}) and resonance integral (I{sub 0}) of the {sup 45}Sc(n,γ){sup 46}Sc reaction have been measured relative to that of the {sup 197}Au(n,γ){sup 198}Au reaction by means of the activation method. High-purity natural scandium and gold foils without and with a cadmium cover of 0.5 mm thickness were irradiated with moderated pulsed neutrons produced from the Pohang Neutron Facility (PNF). The induced activities in the activated foils were measured with a high purity germanium (HPGe) detector. In order to improve the accuracy of the experimental results the counting losses caused by the thermal (G{sub th}) and resonance (G{sub epi}) neutron self-shielding, the γ-ray attenuation (F{sub g}) and the true γ-ray coincidence summing effects were made. In addition, the effect of non-ideal epithermal spectrum was also taken into account by determining the neutron spectrum shape factor (α). The thermal neutron cross-section and resonance integral of the {sup 45}Sc(n,γ){sup 46}Sc reaction have been determined relative to the reference values of the {sup 197}Au(n,γ){sup 198}Au reaction, with σ{sub o,Au} = 98.65 ± 0.09 barn and I{sub o,Au} = 1550 ± 28 barn. The present thermal neutron cross section has been determined to be σ{sub o,Sc} = 27.5 ± 0.8 barn. According to the definition of cadmium cut-off energy at 0.55 eV, the present resonance integral cross section has been determined to be I{sub o,Sc} = 12.4 ± 0.7 barn. The present results are compared with literature values and discussed.
International Nuclear Information System (INIS)
SivaRanjan, Uppala; Ramachandran, Ramesh
2014-01-01
A quantum-mechanical model integrating the concepts of reduced density matrix and effective Hamiltonians is proposed to explain the multi-spin effects observed in rotational resonance (R 2 ) nuclear magnetic resonance (NMR) experiments. Employing this approach, the spin system of interest is described in a reduced subspace inclusive of its coupling to the surroundings. Through suitable model systems, the utility of our theory is demonstrated and verified with simulations emerging from both analytic and numerical methods. The analytic results presented in this article provide an accurate description/interpretation of R 2 experimental results and could serve as a test-bed for distinguishing coherent/incoherent effects in solid-state NMR
Energy Technology Data Exchange (ETDEWEB)
SivaRanjan, Uppala; Ramachandran, Ramesh, E-mail: rramesh@iisermohali.ac.in [Department of Chemical Sciences, Indian Institute of Science Education and Research (IISER) Mohali, Sector 81, Manauli, P.O. Box-140306, Mohali, Punjab (India)
2014-02-07
A quantum-mechanical model integrating the concepts of reduced density matrix and effective Hamiltonians is proposed to explain the multi-spin effects observed in rotational resonance (R{sup 2}) nuclear magnetic resonance (NMR) experiments. Employing this approach, the spin system of interest is described in a reduced subspace inclusive of its coupling to the surroundings. Through suitable model systems, the utility of our theory is demonstrated and verified with simulations emerging from both analytic and numerical methods. The analytic results presented in this article provide an accurate description/interpretation of R{sup 2} experimental results and could serve as a test-bed for distinguishing coherent/incoherent effects in solid-state NMR.
From VHF to UHF CMOS-MEMS Monolithically Integrated Resonators
DEFF Research Database (Denmark)
Teva, Jordi; Berini, Abadal Gabriel; Uranga, A.
2008-01-01
This paper presents the design, fabrication and characterization of microresonators exhibiting resonance frequencies in the VHF and UHF bands, fabricated using the available layers of the standard and commercial CMOS technology, AMS-0.35mum. The resonators are released in a post-CMOS process cons...
Energy Technology Data Exchange (ETDEWEB)
Blaise, P.
1996-12-18
Resonance parameters for actinides play a significant role in the neutronic characteristics of all reactor types. All the major integral parameters strongly depend on the nuclear data of the isotopes in the resonance-energy regions.The author sets up a method for the adjustment of resonance parameters taking into account the self-shielding effects and restricting the cross section deconvolution problem to a limited energy region. (N.T.).
Measurement of resonance integral of the 90Sr(n,γ)91Sr reaction
International Nuclear Information System (INIS)
Nakamura, Shoji; Furutaka, Kazuyoshi; Wada, Hiroaki; Katoh, Toshio; Harada, Hideo; Fujii, Toshiyuki; Yamana, Hajimu
2001-01-01
To obtain fundamental data for research on nuclear transmutation method of radioactive wastes, the resonance integral (I 0 ) of the 90 Sr(n,γ) 91 Sr reaction was measured with an activation method. (author)
Magnetic resonance: safety measures and biological effects
International Nuclear Information System (INIS)
Gordillo, I.; Lafuente, J.; Fernandez, C.; Barbero, M.J.; Cascon, E.
1997-01-01
The biological effects of electromagnetic fields is currently a subject of great controversy. For this reason, magnetic resonance imaging (MRI) and spectroscopy are constantly under investigation. The source of the risk in MRI is associated with the three types of electromagnetic radiation to which the patient is exposed: the static magnetic field, variable (gradient) magnetic fields and radiofrequency fields. Each is capable of producing significant biological effects when employed at sufficient intensity. Patients exposed to risk sources are those situated within the lines of force of the magnetic field, ellipsoid lines that are arranged around the magnet, representing the strength of the surrounding field. To date, at the intensity normally utilized in MRI(<2T) and respecting the field limit recommendations established by the US Food and Drug Administration (FDA) for clinical use of this technique no adverse secondary biological effects have been reported. The known biological effects and other possible secondary effects are reviewed, and the recommended safety measures are discussed. (Author)
The evaluated neutron cross sections and resonance integrals of fission products with Z = 57-62
International Nuclear Information System (INIS)
Fedorova, A.F.; Pisanko, Zh.I.; Novoselov, G.M.
1976-01-01
Neutron cross sections at a neutron velocity of V=2200 m/s, and resonance integrals for fission products with Z=57-71 are estimated. In obtaining the recommended values the results of the neutron cross sections and resonance integrals for elements used as references were normalized in accordance with the latest adjusted values. In the course of estimation, preference was given to the more accurate methods for obtaining the measured values and to the more recent investigations
The evaluated neutron cross sections and resonance integrals of fission products with Z=63-71
International Nuclear Information System (INIS)
Fedorova, A.F.; Pisanko, Zh.I.; Novoselov, G.M.
1976-01-01
Neutron cross sections at a neutron velocity of V=2200 m/s, and the resonance integrals for fission products with Z=63-71 are estimated. In obtaining the recommended values the results were normalized of the neutron cross sections and resonance integrals for elements used as references in accordance with the latest adjusted values. In the course of estimation, preference was given to the more accurate measuring methods and the more recent investigations. Scientific publications up to 1975 have been used
Resonant passive–active vibration absorber with integrated force feedback control
International Nuclear Information System (INIS)
Høgsberg, Jan; Brodersen, Mark L; Krenk, Steen
2016-01-01
A general format of a two-terminal vibration absorber is constructed by placing a passive unit in series with a hybrid unit, composed of an active actuator in parallel with a second passive element. The displacement of the active actuator is controlled by an integrated feedback control with the difference in force between the two passive elements as input. This format allows passive and active contributions to be combined arbitrarily within the hybrid unit, which results in a versatile absorber format with guaranteed closed-loop stability. This is demonstrated for resonant absorbers with inertia realized passively by a mechanical inerter or actively by the integrated force feedback. Accurate calibration formulae are presented for two particular absorber configurations and the performance is subsequently demonstrated with respect to both equal modal damping and effective response reduction. (technical note)
Susceptibility effects in nuclear magnetic resonance imaging
International Nuclear Information System (INIS)
Ziener, Christian Herbert
2008-01-01
The properties of dephasing and the resulting relaxation of the magnetization are the basic principle on which all magnetic resonance imaging methods are based. The signal obtained from the gyrating spins is essentially determined by the properties of the considered tissue. Especially the susceptibility differences caused by magnetized materials (for example, deoxygenated blood, BOLD-effect) or magnetic nanoparticles are becoming more important for biomedical imaging. In the present work, the influence of such field inhomogeneities on the NMR-signal is analyzed. (orig.)
Chip-integrated optical power limiter based on an all-passive micro-ring resonator
Yan, Siqi; Dong, Jianji; Zheng, Aoling; Zhang, Xinliang
2014-10-01
Recent progress in silicon nanophotonics has dramatically advanced the possible realization of large-scale on-chip optical interconnects integration. Adopting photons as information carriers can break the performance bottleneck of electronic integrated circuit such as serious thermal losses and poor process rates. However, in integrated photonics circuits, few reported work can impose an upper limit of optical power therefore prevent the optical device from harm caused by high power. In this study, we experimentally demonstrate a feasible integrated scheme based on a single all-passive micro-ring resonator to realize the optical power limitation which has a similar function of current limiting circuit in electronics. Besides, we analyze the performance of optical power limiter at various signal bit rates. The results show that the proposed device can limit the signal power effectively at a bit rate up to 20 Gbit/s without deteriorating the signal. Meanwhile, this ultra-compact silicon device can be completely compatible with the electronic technology (typically complementary metal-oxide semiconductor technology), which may pave the way of very large scale integrated photonic circuits for all-optical information processors and artificial intelligence systems.
Control of integrated micro-resonator wavelength via balanced homodyne locking.
Cox, Jonathan A; Lentine, Anthony L; Trotter, Douglas C; Starbuck, Andrew L
2014-05-05
We describe and experimentally demonstrate a method for active control of resonant modulators and filters in an integrated photonics platform. Variations in resonance frequency due to manufacturing processes and thermal fluctuations are corrected by way of balanced homodyne locking. The method is compact, insensitive to intensity fluctuations, minimally disturbs the micro-resonator, and does not require an arbitrary reference to lock. We demonstrate long-term stable locking of an integrated filter to a laser swept over 1.25 THz. In addition, we show locking of a modulator with low bit error rate while the chip temperature is varied from 5 to 60° C.
International Nuclear Information System (INIS)
Angell, Christopher T.; Hayakawa, Takehito; Shizuma, Toshiyuki; Hajima, Ryoichi
2013-01-01
Non-destructive assay (NDA) of 239 Pu in spent nuclear fuel or melted fuel using a γ-ray beam is possible using self absorption and the integral resonance transmission method. The method uses nuclear resonance absorption where resonances in 239 Pu remove photons from the beam, and the selective absorption is detected by measuring the decrease in scattering in a witness target placed in the beam after the fuel, consisting of the isotope of interest, namely 239 Pu. The method is isotope specific, and can use photofission or scattered γ-rays to assay the 239 Pu. It overcomes several problems related to NDA of melted fuel, including the radioactivity of the fuel, and the unknown composition and geometry. This talk will explain the general method, and how photofission can be used to assay specific isotopes, and present example calculations. (author)
Magnetodielectric effect of Mn–Zn ferrite at resonant frequency
International Nuclear Information System (INIS)
Pengfei, Pan; Ning, Zhang
2016-01-01
The dielectric properties and the magnetodielectric effect in Mn–Zn ferrite at resonant frequency have been studied in this paper. Dimensional-resonance-induced abnormal dielectric spectrum was observed at f≈1 MHz. The relatively large magnetodielectric ratio of 4500% in a magnetic field of 3.5 kOe was achieved from the Mn–Zn ferrite sample with the initial permeability of 15 K at resonant frequency at room temperature. Theoretical analysis suggests that the large MD effect at resonant frequency is attributed to the enhanced magnetostriction effect. - Highlights: • Dimensional resonance was measured in dielectric spectrum at f≈1 MHz. • The MD ratio of 4500% was induced by H = 3.5 kOe at resonant frequency. • The magnetostriction effect leads to the large MD effect at resonant frequency.
High Frequency LLC Resonant Converter with Magnetic Shunt Integrated Planar Transformer
DEFF Research Database (Denmark)
Li, Mingxiao; Ouyang, Ziwei; Andersen, Michael A. E.
2018-01-01
High Frequency LLC requires a smaller resonant inductance which is usually implemented by transformer leakage inductance. However, this small resonant inductance is difficult to deal with a wide input voltage range. This paper proposes a new method to implement a larger resonant inductance by using...... a magnetic shunt integrated into planar transformer. The switching frequency can be greatly narrowed by designing a smaller inductance ratio of magnetizing inductance to resonant inductance. Since this method can well deal with a wide input voltage range without adding extra inductor and increasing the size...... of the transformer, the power density can be improved. The precise leakage inductance calculation method for this transformer and detailed LLC converter design procedure are presented. A 280-380V and 48V-100W half bridge LLC resonant converter with 1 MHz resonant frequency is built to verify the design methodology....
Geometrical resonance effects in thin superconducting films
International Nuclear Information System (INIS)
Nedellec, P.
1977-01-01
Electron tunneling density of states measurements on thick and clear superconducting films (S 1 ) backed by films in the normal or superconducting state (S 2 ) show geometrical resonance effects associated with the spatial variation of Δ(x), the pair potential, near the interface S 1 -S 2 . The present understanding of this so-called 'Tomasch effect' is described. The dispersion relation and the nature of excitations in the superconducting state are introduced. It is shown that the introduction of Green functions give a general description of the superconducting state. The notion of Andreev scattering at the S 1 -S 2 interface is presented and connect the geometrical resonance effects to interference process between excitations. The different physical parameters involved are defined and used in the discussion of some experimental results: the variation of the period in energy with the superconducting thickness is connected to the renormalized group velocity of excitations traveling perpendicular to the film. The role of the barrier potential at the interface on the Tomasch effect is described. The main results discussed are: the decrease of the amplitude of the Tomasch structures with energy is due to the loss of the mixed electron-hole character of the superconducting excitations far away from the Fermi level; the variation of the pair potential at the interface is directly related to the amplitude of the oscillations; the tunneling selectivity is an important parameter as the amplitude as well as the phase of the oscillations are modified depending on the value of the selectivity; the phase of the Tomasch oscillations is different for an abrupt change of Δ at the interface and for a smooth variation. An ambiguity arises due to the interplay between these parameters. Finally, some experiments, which illustrate clearly the predicted effects are described [fr
Reflection effect of localized absorptive potential on non-resonant and resonant tunneling
International Nuclear Information System (INIS)
Rubio, A.; Kumar, N.
1992-06-01
The reflection due to absorptive potential (-iV i ) for resonant and non-resonant tunneling has been considered. We show that the effect of reflection leads to a non-monotonic dependence of absorption on the strength V i with a maximum absorption of typically 0.5. This has implications for the operation of resonant tunneling devices. General conceptual aspects of absorptive potentials are discussed. (author). 9 refs, 2 figs
Photon cooperative effect in resonance spectroscopy
International Nuclear Information System (INIS)
Veklenko, B.A.
1998-01-01
A systematic method is proposed for calculating the density matrix of subsystems interacting with their environment under conditions of thermodynamic equilibrium. The density matrix of photons resonantly interacting with a surrounding gas is calculated. It is shown that use of the Gibbs distribution allows one to completely eliminate inelastic processes from the calculations. A correct account of photon-photon correlators indicates the presence of new cooperative effects. A new branch of the polariton spectrum is predicted, which is due to the presence of excited atoms in the medium. With the help of the density matrix the mean filling numbers of the photon modes are calculated. In terms of wavelengths, we have obtained a generalization of the Planck formula which accounts for photon cooperative phenomena. The manifestation of these effects in kinetic processes is discussed
Resonance effects in neutron scattering lengths
Energy Technology Data Exchange (ETDEWEB)
Lynn, J.E.
1989-06-01
The nature of neutron scattering lengths is described and the nuclear effects giving rise to their variation is discussed. Some examples of the shortcomings of the available nuclear data base, particularly for heavy nuclei, are given. Methods are presented for improving this data base, in particular for obtaining the energy variation of the complex coherent scattering length from long to sub-/angstrom/ wave lengths from the available sources of slow neutron cross section data. Examples of this information are given for several of the rare earth nuclides. Some examples of the effect of resonances in neutron reflection and diffraction are discussed. This report documents a seminar given at Argonne National Laboratory in March 1989. 18 refs., 18 figs.
Resonance effects in neutron scattering lengths
International Nuclear Information System (INIS)
Lynn, J.E.
1989-01-01
The nature of neutron scattering lengths is described and the nuclear effects giving rise to their variation is discussed. Some examples of the shortcomings of the available nuclear data base, particularly for heavy nuclei, are given. Methods are presented for improving this data base, in particular for obtaining the energy variation of the complex coherent scattering length from long to sub-angstrom wave lengths from the available sources of slow neutron cross section data. Examples of this information are given for several of the rare earth nuclides. Some examples of the effect of resonances in neutron reflection and diffraction are discussed. This report documents a seminar given at Argonne National Laboratory in March 1989. 18 refs., 18 figs
Effect of resonance line shape on precision measurements of nuclear magnetic resonance shifts
International Nuclear Information System (INIS)
Kachurin, A.M.; Smelyanskij, A.Ya.
1986-01-01
Effect of resonance line shape on the systematic error of precision measurements of nuclear magnetic resonance (NMR) shifts of high resolution (on the center of NMR dispersion line) is analysed. Effect of the device resonance line form-function asymmetry is evaluated; the form-function is determined by configuration of the spectrometer magnetic field and enters the convolution, which describes the resonance line form. It is shown that with the increase of the relaxation line width the form-function effect on the measurement error yields to zero. The form-function effect on measurements and correction of a phase angle of NMR detection is evaluated. The method of semiquantitative evaluation of resonance line and NMR spectrometer parameters, guaranteeing the systematic error of the given infinitesimal, is presented
Non-integrability of first order resonances in Hamiltonian systems in three degrees of freedom
Christov, Ognyan
2012-02-01
The normal forms of the Hamiltonian 1:2: ω resonances to degree three for ω = 1, 3, 4 are studied for integrability. We prove that these systems are non-integrable except for the discrete values of the parameters which are well known. We use the Ziglin-Morales-Ramis method based on the differential Galois theory.
Monte Carlo-narrow resonance calculational techniques for treating double-heterogeneity effects
International Nuclear Information System (INIS)
Gelbard, E.M.; Chen, I.J.
1986-01-01
Reliable methods already exist for computing resonance integrals (RI's) in regular lattices. But lattice structures always contain irregularities. Such effects have been called ''double-heterogeneity'' effects. Two methods for computing double heterogeneity effects on RI's are reviewed and evaluated. 2 refs., 1 tab
Photo-Detectors Integrated with Resonant Tunneling Diodes
Directory of Open Access Journals (Sweden)
José M. L. Figueiredo
2013-07-01
Full Text Available We report on photo-detectors consisting of an optical waveguide that incorporates a resonant tunneling diode (RTD. Operating at wavelengths around 1.55 μm in the optical communications C band we achieve maximum sensitivities of around 0.29 A/W which is dependent on the bias voltage. This is due to the nature of RTD nonlinear current-voltage characteristic that has a negative differential resistance (NDR region. The resonant tunneling diode photo-detector (RTD-PD can be operated in either non-oscillating or oscillating regimes depending on the bias voltage quiescent point. The oscillating regime is apparent when the RTD-PD is biased in the NDR region giving rise to electrical gain and microwave self-sustained oscillations Taking advantage of the RTD’s NDR distinctive characteristics, we demonstrate efficient detection of gigahertz (GHz modulated optical carriers and optical control of a RTD GHz oscillator. RTD-PD based devices can have applications in generation and optical control of GHz low-phase noise oscillators, clock recovery systems, and fiber optic enabled radio frequency communication systems.
Energy Technology Data Exchange (ETDEWEB)
Kocic, A; Markovic, V [Institute of nuclear sciences Boris Kidric, Vinca, Beograd (Yugoslavia)
1967-04-15
Zirconium and zircaloy-2 alloy, as constructive materials, have found wide application in reactor technology, especially in heavy water systems for two reasons: a) low neutron absorption cross section, b) good mechanical properties. The thickness of the zirconium and zircaloy-2 for different applications varies from several tenths of a millimeter to about ten millimeters. Therefore, to calculate reactor systems it is desirable to know the effective neutron absorption cross section for the range of thicknesses mention above. The thermal neutron cross sections for these materials are low and no appreciable variation of the effective neutron cross section occurs even for the largest thicknesses. However, this is not true for effective resonance absorption. On the other hand, due to the lack of detailed knowledge of the zirconium resonances, calculations of the effective resonance integrals cannot be performed. Therefore it is necessary to measure the effective total and resonance absorption cross section for zirconium (author)
Energy Technology Data Exchange (ETDEWEB)
Siwak, N. P. [Department of Electrical and Computer Engineering, Institute for Systems Research, University of Maryland, College Park, Maryland 20742 (United States); Laboratory for the Physical Sciences, 8050 Greenmead Drive, College Park, Maryland 20740 (United States); Fan, X. Z.; Ghodssi, R. [Department of Electrical and Computer Engineering, Institute for Systems Research, University of Maryland, College Park, Maryland 20742 (United States); Kanakaraju, S.; Richardson, C. J. K. [Laboratory for the Physical Sciences, 8050 Greenmead Drive, College Park, Maryland 20740 (United States)
2014-10-06
An integrated photodiode displacement readout scheme for a microelectromechanical cantilever waveguide resonator sensing platform is presented. III-V semiconductors are used to enable the monolithic integration of passive waveguides with active optical components. This work builds upon previously demonstrated results by measuring the displacement of cantilever waveguide resonators with on-chip waveguide PIN photodiodes. The on-chip integration of the readout provides an additional 70% improvement in mass sensitivity compared to off-chip photodetector designs due to measurement stability and minimized coupling loss. In addition to increased measurement stability, reduced packaging complexity is achieved due to the simplicity of the readout design. We have fabricated cantilever waveguides with integrated photodetectors and experimentally characterized these cantilever sensors with monolithically integrated PIN photodiodes.
{sup 41}K(n, {gamma}){sup 42}K thermal and resonance integral cross section measurements
Energy Technology Data Exchange (ETDEWEB)
Ferreira, F.A. Jr.; Maidana, N.L.; Vanin, V.R. [Sao Paulo Univ., SP (Brazil). Lab. do Acelerador Linear; Dias, M.S.; Koskinas, M.F. [IPEN-CNEN, Sao Paulo, SP (Brazil). Lab. de Metrolgia Nuclear; Lopez-Pino, N. [Instituto Superior de Tecnolgias y Ciencias Aplicadas (InSTEC), Habana (Cuba)
2012-07-01
We measured the {sup 41}K thermal neutron absorption and resonance integral cross sections after the irradiation of KNO{sub 3} samples near the core of the IEA-R1 IPEN pool-type research reactor. Bare and cadmium-covered targets were irradiated in pairs with Au-Al alloy flux-monitors. The residual activities were measured by gamma-ray spectroscopy with a HPGe detector, with special care to avoid the {sup 42}K decay {beta}{sup -} emission effects on the spectra. The gamma-ray self-absorption was corrected with the help of MCNP simulations. We applied the Westcott formalism in the average neutron flux determination and calculated the depression coefficients for thermal and epithermal neutrons due to the sample thickness with analytical approximations. We obtained 1.57(4) b and 1.02(4) b, for thermal and resonance integral cross sections, respectively, with correlation coefficient equal to 0.39.
Simulation of Helmholtz Resonance Effects in Aircraft ECS
Pollok, Alexander; Schröffer, Andreas
2017-01-01
Helmholtz resonators are closed volumes that are connected to pipes. They exhibit a pronounced resonance frequency, where small boundary pressure excitations in the volume or the environment lead to large mass flow excitations in the pipe. Aircraft have a topology similar to Helmholtz resonators, the closed volume is represented by the cabin, while the pipe is represented by the Environmental Control System. Some discrepancies appear due to the non-zero mass-flow or friction effects in...
Micro-resonators based on integrated polymer technology for optical sensing
Girault , Pauline; Lemaitre , Jonathan; Guendouz , Mohammed; Lorrain , Nathalie; Poffo , Luiz; Gadonna , Michel; Bosc , Dominique
2014-01-01
International audience; Research on sensors has experienced a noticeable development over the last decades especially in label free optical biosensors. However, compact sensors without markers for rapid, reliable and inexpensive detection of various substances induces a significant research of new technological solutions. The context of this work is the development of a sensor based on easily integrated and inexpensive micro-resonator (MR) component in integrated optics, highly sensitive and ...
INTER, ENDF/B Thermal Cross-Sections, Resonance Integrals, G-Factors Calculation
International Nuclear Information System (INIS)
Dunford, Charles L.
2007-01-01
1 - Description of program or function: INTER calculates thermal cross sections, g-factors, resonance integrals, fission spectrum averaged cross sections and 14.0 MeV (or other energy) cross sections for major reactions in an ENDF-6 or ENDF-5 format data file. Version 7.01 (Jan 2005): set success flag after return from beginning. 2 - Method of solution: INTER performs integrations by using the trapezoidal rule
Measurement and Evaluation of the Activation Resonance Integral of 146Nd, 148Nd and 150Nd
International Nuclear Information System (INIS)
Ricabarra, M. D.; Turjanski, R.; Ricabarra, G. H.
2012-01-01
Values of the ratio of the reduced activation resonance integral to the thermal cross section, I'/σ 0 of 146 Nd, 148 Nd and 150 Nd were determined relative to gold by measuring cadmium ratios. A lithium-drifted germanium gamma ray spectrometer was used to resolve the activities of the irradiated samples. The results are for 146 Nd I'/σ 0 = 1.42±0.1 0 and with an assumed σ 0 = 1.4 barn, I' = 1 .99±0.20; for 148 Nd I'/ σ 0 = 4.22±0.1 4 and with an assumed σ 0 = 2.5 barn, I' = 10.5±0. 9 barn, and for 150 Nd I'/σ 0 = 13.7±0. 8 and with an assumed σ 0 = 1.2 barn, I' = 16.4±2.8. The resolved and unresolved epithermal integrals of 146 Nd, 148 Nd and 150 Nd were calculated. Values of the spectral correction factor were also calculated, so the resonance integral could be obtained from the epithermal integral data measured in our reactor spectrum in this experiment. Epithermal integral and spectral correction factors are listed in the text. The most important result of this investigation is that the 148 Nd activation reduced resonance integral is about half of the previously recommended value and consequently the radiative width for 148 Nd is also about half of the previously accepted value. (author)
Influence of the resonance integral value on the fuel cycle characteristics
Energy Technology Data Exchange (ETDEWEB)
Graziani, G; Trauwaert, E
1972-04-24
The problem that is considered here is to determine what can be done about a variation in resonance integral when the complete geometry of the reactor and of the fuel elements are fixed, leaving as only free parameters the amount of heavy metal and the enrichment to put in the fuel pins.
Low insertion loss SOI microring resonator integrated with nano-taper couplers
DEFF Research Database (Denmark)
Pu, Minhao; Frandsen, Lars Hagedorn; Ou, Haiyan
2009-01-01
We demonstrate a microring resonator working at TM mode integrated with nano-taper couplers with 3.6dB total insertion loss. The measured insertion loss of the nano-taper coupler was only 1.3dB for TM mode....
Resonance integral calculations for isolated rods containing oxides of 238U and 232Th
International Nuclear Information System (INIS)
Baker, V.C.; Marable, J.H.
1980-02-01
Results of resonance integral calculations for UO 2 and ThO 2 isolated rods are discussed. The calculations were performed with ENDF/B-IV cross-section data and the multigroup transport code ANISN. The findings reported demonstrate by comparison with semiempirical relationships (based on experimentally derived results) the suitability of the method used for determining resonance integrals. The calculations were based on a cylindrical rod in an H 2 O moderator of large radius. Multigroup cross sections were obtained by a MINX-SPHINX-AMMPX sequence, and ANISN was used to account for the neutron flux and capture rates. A special approach was used to determine a neutron source distribution such that the flux in the moderator region was forced to behave in an asymptotic way; thus, the ideal resonance integral experiment could be calculated. The UO 2 resonance integrals calculated were in exceptionally good agreement with experimental values based on isolated rods. The ThO 2 results were approximately 6% lower than experimental values, and efforts to understand the discrepancy are discussed. 8 figures, 7 tables
Magnetically integrated high step-up resonant DC-DC converter for distributed photovoltaic systems
DEFF Research Database (Denmark)
Vinnikov, Dmitri; Chub, Andrii; Liivik, Elizaveta
2017-01-01
In this paper magnetically integrated resonant single-switch quasi-Z-source DC-DC converter is evaluated as a candidate topology for the low-cost photovoltaic microconverter. The derivation of the topology and its basic operation principle are explained. Generalized design guidelines...
Monolithic integration of a resonant tunneling diode and a quantum well semiconductor laser
Grave, I.; Kan, S. C.; Griffel, G.; Wu, S. W.; Sa'Ar, A.
1991-01-01
A monolithic integration of a double barrier AlAs/GaAs resonant tunneling diode and a GaAs/AlGaAs quantum well laser is reported. Negative differential resistance and negative differential optical response are observed at room temperature. The device displays bistable electrical and optical characteristics which are voltage controlled. Operation as a two-state optical memory is demonstrated.
International Nuclear Information System (INIS)
Holden, N.E.
1994-01-01
A re-evaluation of all thermal neutron cross sections and neutron resonance integrals has been performed, utilizing the previous database of the ''Barn Book'' and all of the more recently published experiments. Only significant changes or previously undetermined values are recorded in this report. The source for each value is also recorded in the accompanying table
Resonant Effects in Neutral beam Moderation at TJ-II
International Nuclear Information System (INIS)
Guasp, J.; Liniers, M.; Fuentes, C.
1999-01-01
The structure of fast ion losses in neutral beam moderation at TJ-II is analysed theoretically, in particular the influence of resonant effects and the radial electric field dependence. The direct losses show strong resonant effects when the ratio of the poloidal and toroidal rotation velocities pass near the values -4/3, -2 or 0. These effects are visible as strong maxima on the loss fractions and also as characteristic trajectory behaviours. The delayed losses present resonant effects also, generally at intermediate energies (5 to 20 KeV for 40 keV injection). Near the resonances the population of passing particles in these losses is very high and the loss fraction can equal or even surpass the direct losses. In these delayed losses the particles concentrate along vertical strips on the loss cone diagrams of roughly constant parallel velocity. This parallel velocity increases with the electric field, the loss maxima are reached usually when the pitch and energy of these strips are near the initial injection values. The trapped particle population in these delayed losses is maximal at null electric and decreases with the field intensity for both potential signs. The corresponding final energies are usually low (1 to 5 keV). Except at extreme potentials, where the -4 resonance can appear, no resonant effects are observed for this population. The resonance ordering is similar for all configurations and follows reasonably the predictions of a simple model. The extreme configurations are dominated by the effects of the 0 and -2 resonances, giving very high loss fractions even for null electric field. In contrast the intermediate configurations, near the Reference one, do not present resonant effects and the losses are moderate at low potentials. Only above 2000 v the resonant effects start to appear. (Author) 11 refs
DEFF Research Database (Denmark)
Petersen, Nils Holger
2014-01-01
A chapter in a book about terminology within the field of medievalism: the chapter discusses the resonance of medieval music and ritual in modern (classical) music culture and liturgical practice.......A chapter in a book about terminology within the field of medievalism: the chapter discusses the resonance of medieval music and ritual in modern (classical) music culture and liturgical practice....
International Nuclear Information System (INIS)
Belanova, T.S.
1994-12-01
Data on the thermal neutron fission and capture cross-sections as well as their corresponding resonance integrals are reviewed and analysed. The data are classified according to the form of neutron spectra under investigation. The weighted mean values of the cross-sections and resonance integrals for every type of neutron spectra were adopted as evaluated data. (author). 87 refs, 2 tabs
International Nuclear Information System (INIS)
Schwenk, G.A. Jr.
1980-01-01
The calculation of neutron-nuclei reaction rates in the lower resolved resonance region (167 eV - 1.855 eV) is considered in this dissertation. Particular emphasis is placed on the calculation of these reaction rates for tight lattices where their accuracy is most important. The results of the continuous energy Monte Carlo code, VIM, are chosen as reference values for this study. The primary objective of this work is to develop a method for calculating resonance reaction rates which agree well with the reference solution, yet is efficient enough to be used by nuclear reactor fuel cycle designers on a production basis. A very efficient multigroup solution of the two spatial region energy dependent integral transport equation is developed. This solution, denoted the Broad Group Integral Method (BGIM), uses escape probabilities to obtain the spatial coupling between regions and uses an analytical flux shape within a multigroup to obtain weighted cross sections which account for the rapidly varying resonance cross sections. The multigroup lethargy widths chosen for the numerical integration of the two region energy-dependent neutron continuity equations can be chosen much wider (a factor of 30 larger) than in the direct numerical integration methods since the analytical flux shape is used to account for fine structure effects. The BGIM solution is made highly efficient through the use of these broad groups. It is estimated that for a 10 step unit cell fuel cycle depletion calculation, the computer running time for a production code such as EPRI-LEOPARD would be increased by only 6% through the use of the more accurate and intricate BGIM method in the lower resonance energy region
First experimental results on CMOS Integrated Nickel Electroplated Resonators
DEFF Research Database (Denmark)
Yalcinkaya, Arda Deniz; Hansen, Ole
2004-01-01
This paper presents experimental results on MEMS metallic add-on post-fabrication effects on complementary metal oxide semiconductor (CMOS) transistors. Two versions of add-on processing, that use either e-beam evaporation or magnetron sputtering, are compared through investigation of the electri...
Ionic core effects on the Mie resonance in lithium clusters
International Nuclear Information System (INIS)
Yabana, K.
1994-01-01
We investigate effects of atomic cores on the Mie resonance in lithium metal clusters, perturbing a helium Hamiltonian with zero-range pseudopotentials. The resonance is red-shifted with respect to the classical formula by core effects, most important of which is the increased effective mass due to the core potentials. Much of the large shift seen in lithium clusters is thereby explained if the strength of the Pseudopotentials is taken from band structure calculations. However, such pseudopotentials cause the resonance to be greatly broadened, contrary to observation
Substrate effects on terahertz metamaterial resonances for various metal thicknesses
International Nuclear Information System (INIS)
Park, S. J.; Ahn, Y. H.
2014-01-01
We demonstrate dielectric substrate effects on the resonance shift of terahertz metamaterials with various metal thicknesses by using finite-difference time-domain simulations. We found a small red shift in the metamaterial resonance with increasing metal thickness for the free-standing case. Conversely, when the metamaterial pattern was supported by a substrate with a high dielectric constant, the resonant frequency exhibited a large blue shift because the relative contribution of the substrate's refractive index to the resonant frequency decreased drastically as we increased the metal thickness. We determined the substrate's refractive index, 1.26, at which the metamaterial resonance was independent of the metal thickness. We extracted the effective refractive index as a function of the substrate's refractive index explicitly, which was noticeably different for different film thicknesses.
"Cul-de-sac" microstrip resonators for high-speed integrated optical commutator switches
Jaeger, Nicolas A.; Chen, Mingche
1993-04-01
A novel microstrip resonator structure for use with integrated Y-branch optical modulators fabricated in Ti:LiNbO3 is proposed. The legs of the structure are intended to act as the electrodes of the modulator, with light being directed into each of the output waveguides of the Y-branch on alternate half-cycles of the standing wave excited in the resonator; forming an optical commutator switch. Such resonators having Al2O3 substrates were designed, fabricated, and tested. Measurements on one such resonator, operating at 7.12 GHz and having an unloaded quality factor of 123, indicating that 50 V should develop across the ends of its legs for 35 mW dissipated power; the corresponding values, from the model used to design the resonator, were 179, 50 V,and 24 mW, respectively. Using the model it is shown that a similar resonator fabricated on LiNbO3 should be able to develop about 50 V for 100 mW dissipated power at 15 GHz.
Characterization of resonances using finite size effects
International Nuclear Information System (INIS)
Pozsgay, B.; Takacs, G.
2006-01-01
We develop methods to extract resonance widths from finite volume spectra of (1+1)-dimensional quantum field theories. Our two methods are based on Luscher's description of finite size corrections, and are dubbed the Breit-Wigner and the improved ''mini-Hamiltonian'' method, respectively. We establish a consistent framework for the finite volume description of sufficiently narrow resonances that takes into account the finite size corrections and mass shifts properly. Using predictions from form factor perturbation theory, we test the two methods against finite size data from truncated conformal space approach, and find excellent agreement which confirms both the theoretical framework and the numerical validity of the methods. Although our investigation is carried out in 1+1 dimensions, the extension to physical 3+1 space-time dimensions appears straightforward, given sufficiently accurate finite volume spectra
The effects of 3:1 resonances in stellar pulsations
International Nuclear Information System (INIS)
Moskalik, P.; Buchler, J.R.
1989-01-01
The effects of a 3:1 resonance are studied and compared to those of a 2:1 resonance. When the growth rate of the higher frequency mode is negative it is shown that a 3:1 resonance affects the pulsation in a very similar fashion to a 2:1 resonance. In fact, it may be very difficult to discriminate in observational data between these two types of coupling. On the other hand, when the higher frequency mode is linearly unstable a 3:1 resonance, contrary to a 2:1 case, is unable to saturate the instability in the absence of nonresonant coupling terms. Astrophysical applications are discussed. 19 refs
Studies of the Effective Total and Resonance Absorption Cross Sections for Zircaloy 2 and Zirconium
Energy Technology Data Exchange (ETDEWEB)
Hellstrand, E; Lindahl, G; Lundgren, G
1961-06-15
Using pile oscillator technique, the total absorption cross section for zircaloy 2 plates has been determined in the neutron spectrum of the reactor R1. The plate thickness was varied in six steps from 0. 2 mm to 6. 4 mm. The thermal cross section for the alloy was calculated from cross section data and the known composition of the alloy. By subtracting this value from the measured cross sections and dividing by the factor {alpha}=2/{radical}({pi}) x r x {radical}(T/T{sub 0}) the effective resonance integrals were obtained. After subtraction of a constant amount for resonance contributions from hafnium, tin etc., effective resonance integrals for zirconium could be evaluated. An extrapolated value of 0.85 {+-} 0.15 b was obtained for the infinitely dilute integral (l/v part excluded). The ratio of the resonance integral at plate thicknesses 0.2 and 6.4 mm came out as 1.65 {+-} 0.25.
Giant resonance effects in radiative capture
International Nuclear Information System (INIS)
Snover, K.A.
1979-01-01
The technique of capture reaction studies of giant resonance properties is described, and a number of examples are given. Most of the recent work of interest has been in proton capture, in part because of the great utility (and availability) of polarized beams; most of the discussion concerns this reaction. Alpha capture, which has been a useful tool for exploring isoscalar E2 strength, and neutron capture are, however, also treated. 46 references, 14 figures
Integrated phononic crystal resonators based on adiabatically-terminated phononic crystal waveguides
Directory of Open Access Journals (Sweden)
Razi Dehghannasiri
2016-12-01
Full Text Available In this letter, we demonstrate a new design for integrated phononic crystal (PnC resonators based on confining acoustic waves in a heterogeneous waveguide-based PnC structure. In this architecture, a PnC waveguide that supports a single mode at the desired resonance frequencies is terminated by two waveguide sections with no propagating mode at those frequencies (i.e., have mode gap. The proposed PnC resonators are designed through combining the spatial-domain and the spatial-frequency domain (i.e., the k-domain analysis to achieve a smooth mode envelope. This design approach can benefit both membrane-based and surface-acoustic-wave-based architectures by confining the mode spreading in k-domain that leads to improved electromechanical excitation/detection coupling and reduced loss through propagating bulk modes.
Directory of Open Access Journals (Sweden)
Jian Li
2016-09-01
Full Text Available A high-overtone bulk acoustic resonator (HBAR consisting of a piezoelectric film with two electrodes on a substrate exhibits a high quality factor (Q and multi-mode resonance spectrum. By analyzing the influences of each layer’s material and structure (thickness parameters on the effective electromechanical coupling coefficient (Keff2, the resonance spectrum characteristics of Keff2 have been investigated systematically, and the optimal design of HBAR has been provided. Besides, a device, corresponding to one of the theoretical cases studied, is fabricated and evaluated. The experimental results are basically consistent with the theoretical results. Finally, the effects of Keff2 on the function of the crystal oscillators constructed with HBARs are proposed. The crystal oscillators can operate in more modes and have a larger frequency hopping bandwidth by using the HBARs with a larger Keff2·Q.
Bourke, Levi; Blaikie, Richard J
2017-12-01
Dielectric waveguide resonant underlayers are employed in ultra-high NA interference photolithography to effectively double the depth of field. Generally a single high refractive index waveguiding layer is employed. Here multilayer Herpin effective medium methods are explored to develop equivalent multilayer waveguiding layers. Herpin equivalent resonant underlayers are shown to be suitable replacements provided at least one layer within the Herpin trilayer supports propagating fields. In addition, a method of increasing the intensity incident upon the photoresist using resonant overlayers is also developed. This method is shown to greatly enhance the intensity within the photoresist making the use of thicker, safer, non-absorbing, low refractive index matching liquids potentially suitable for large-scale applications.
A warning on fission resonance intergrals: Caveat utor
International Nuclear Information System (INIS)
Holden, N.E.
1988-01-01
A common error is made in defining the resonance integral in most tabulations and handbooks. Although it has a minor effect on the capture resonance integral and on the fission resonance integral for the fissile nuclides, it leads to gross errors in the fission resonance integral for the fertile nuclides. The errors in the fission resonance integral for fertile nuclides of the elements from thorium through curium in the ENDF/B-V library will be presented. Let the user beware
International Nuclear Information System (INIS)
Meftah, B.; Karam, R.A.
1984-01-01
Agreement between calculations and measurements within prescribed limits of error is always the test of engineering design analysis. Large and puzzling discrepancies do exist between several measured and calculated important integral reactor parameters. A thorough and exhaustive investigation of the methods used in reactor analysis revealed that in the generation of effective resonance cross sections no anisotropy effects are considered in the resonances. This is true in the integral transport and fundamental-mode codes. The neglect of anisotropy introduces errors at two levels: (1) the effective group cross sections such as σsub(c), σsub(f) and σsub(s); and (2) the diffusion coefficients and P 1 and higher components of the scattering cross sections. The study showed that the inclusion of linear scattering anisotropy increases, in general, the cell effective capture cross section of 238 U in both ZPR-6/5 and TRX-3 reactors. The increase was up to 2% in TRX-3 and 0.5% in ZPR-6/5. The effect on the multiplication factor was -0.003% Δk/k for ZPR-6/5 and -0.05% Δk/k for TRX-3. (author)
ISR effects for resonant Higgs production at future lepton colliders
Directory of Open Access Journals (Sweden)
Mario Greco
2016-12-01
Full Text Available We study the effects of the initial state radiation on the s-channel Higgs boson resonant production at μ+μ− and e+e− colliders by convoluting with the beam energy spread profile of the collider and the Breit–Wigner resonance profile of the signal. We assess their impact on both the Higgs signal and SM backgrounds for the leading decay channels h→bb¯, WW⁎. Our study improves the existing analyses of the proposed future resonant Higgs factories and provides further guidance for the accelerator designs with respect to the physical goals.
DEFF Research Database (Denmark)
an impetus or drive to that account: change, innovation, rupture, or discontinuity. Resonances: Historical Essays on Continuity and Change explores the historiographical question of the modes of interrelation between these motifs in historical narratives. The essays in the collection attempt to realize...
Regeta, Khrystyna; Allan, Michael; Winstead, Carl; McKoy, Vincent; Mašín, Zdeněk; Gorfinkiel, Jimena D
2016-01-14
We measured differential cross sections for elastic (rotationally integrated) electron scattering on pyrimidine, both as a function of angle up to 180(∘) at electron energies of 1, 5, 10, and 20 eV and as a function of electron energy in the range 0.1-14 eV. The experimental results are compared to the results of the fixed-nuclei Schwinger variational and R-matrix theoretical methods, which reproduce satisfactorily the magnitudes and shapes of the experimental cross sections. The emphasis of the present work is on recording detailed excitation functions revealing resonances in the excitation process. Resonant structures are observed at 0.2, 0.7, and 4.35 eV and calculations for different symmetries confirm their assignment as the X̃(2)A2, Ã(2)B1, and B̃(2)B1 shape resonances. As a consequence of superposition of coherent resonant amplitudes with background scattering the B̃(2)B1 shape resonance appears as a peak, a dip, or a step function in the cross sections recorded as a function of energy at different scattering angles and this effect is satisfactorily reproduced by theory. The dip and peak contributions at different scattering angles partially compensate, making the resonance nearly invisible in the integral cross section. Vibrationally integrated cross sections were also measured at 1, 5, 10 and 20 eV and the question of whether the fixed-nuclei cross sections should be compared to vibrationally elastic or vibrationally integrated cross section is discussed.
Nonlinear Resonance Islands and Modulational Effects in a Proton Synchrotron
Energy Technology Data Exchange (ETDEWEB)
Satogata, Todd Jeffrey [Northwestern Univ., Evanston, IL (United States)
1993-01-01
We examine both one-dimensional and two-dimensional nonlinear resonance islands created in the transverse phase space of a proton synchrotron by nonlinear magnets. We also examine application of the theoretical framework constructed to the phenomenon of modulational diffusion in a collider model of the Fermilab Tevatron. For the one-dimensional resonance island system, we examine the effects of two types of modulational perturbations on the stability of these resonance islands: tune modulation and beta function modulation. Hamiltonian models are presented which predict stability boundaries that depend on only three paramders: the strength and frequency of the modulation and the frequency of small oscillations inside the resonance island. These. models are compared to particle tracking with excellent agreement. The tune modulation model is also successfully tested in experiment, where frequency domain analysis coupled with tune modulation is demonstrated to be useful in measuring the strength of a nonlinear resonance. Nonlinear resonance islands are also examined in two transverse dimensions in the presence of coupling and linearly independent crossing resonances. We present a first-order Hamiltonian model which predicts fixed point locations, but does not reproduce small oscillation frequencies seen in tracking; therefore in this circumstance such a model is inadequate. Particle tracking is presented which shows evidence of two-dimensional persistent signals, and we make suggestions on methods for observing such signals in future experiment.
Single-frequency, fully integrated, miniature DPSS laser based on monolithic resonator
Dudzik, G.; Sotor, J.; Krzempek, K.; Soboń, G.; Abramski, K. M.
2014-02-01
We present a single frequency, stable, narrow linewidth, miniature laser sources operating at 532 nm (or 1064 nm) based on a monolithic resonators. Such resonators utilize birefringent filters formed by YVO4 beam displacer and KTP or YVO4 crystals to force single frequency operation at 532 nm or 1064 nm, respectively. In both configurations Nd:YVO4 gain crystal is used. The resonators dimensions are 1x1x10.5 mm3 and 1x1x8.5 mm3 for green and infrared configurations, respectively. Presented laser devices, with total dimensions of 40x52x120 mm3, are fully equipped with driving electronics, pump diode, optical and mechanical components. The highly integrated (36x15x65 mm3) low noise driving electronics with implemented digital PID controller was designed. It provides pump current and resonator temperature stability of ±30 μA@650 mA and ±0,003ºC, respectively. The laser parameters can be set and monitored via the USB interface by external application. The developed laser construction is universal. Hence, the other wavelengths can be obtained only by replacing the monolithic resonator. The optical output powers in single frequency regime was at the level of 42 mW@532 nm and 0.5 W@1064 nm with the long-term fluctuations of ±0.85 %. The linewidth and the passive frequency stability under the free running conditions were Δν < 100 kHz and 3ṡ10-9@1 s integration time, respectively. The total electrical power supply consumption of laser module was only 4 W. Presented compact, single frequency laser operating at 532 nm and 1064 nm may be used as an excellent source for laser vibrometry, interferometry or seed laser for fiber amplifiers.
International Nuclear Information System (INIS)
Slipicevic, K.
1968-12-01
Following a review of the existing theories od resonance absorption this thesis includes a new approach for calculating the effective resonance integral of absorbed neutrons, new approximate formula for the penetration factor, an analysis of the effective resonance integral and the correction of the resonance integral taking into account the interference of potential and resonance dissipation. A separate chapter is devoted to calculation of the effective resonance integral for the regular reactor lattice with cylindrical fuel elements
Integrability of the Gross-Pitaevskii equation with Feshbach resonance management
International Nuclear Information System (INIS)
Zhao Dun; Luo Honggang; Chai Huayue
2008-01-01
In this Letter we study the integrability of a class of Gross-Pitaevskii equations managed by Feshbach resonance in an expulsive parabolic external potential. By using WTC test, we find a condition under which the Gross-Pitaevskii equation is completely integrable. Under the present model, this integrability condition is completely consistent with that proposed by Serkin, Hasegawa, and Belyaeva [V.N. Serkin, A. Hasegawa, T.L. Belyaeva, Phys. Rev. Lett. 98 (2007) 074102]. Furthermore, this integrability can also be explicitly shown by a transformation, which can convert the Gross-Pitaevskii equation into the well-known standard nonlinear Schroedinger equation. By this transformation, each exact solution of the standard nonlinear Schroedinger equation can be converted into that of the Gross-Pitaevskii equation, which builds a systematical connection between the canonical solitons and the so-called nonautonomous ones. The finding of this transformation has a significant contribution to understanding the essential properties of the nonautonomous solitons and the dynamics of the Bose-Einstein condensates by using the Feshbach resonance technique
Mortada, O.; Zahr, A. H.; Orlianges, J.-C.; Crunteanu, A.; Chatras, M.; Blondy, P.
2017-02-01
This paper reports on the design, simulation, fabrication, and test results of ZnO-based contour-mode micro-resonators integrating piezoelectric zinc oxide (ZnO) layers. The inter-digitated (IDT) type micro-resonators are fabricated on ZnO films and suspended top of 2 μm thick silicon membranes using silicon-on insulator technology. We analyze several possibilities of increasing the quality factor (Q) and the electromechanical coupling coefficient (kt2) of the devices by varying the numbers and lengths of the IDT electrodes and using different thicknesses of the ZnO layer. We designed and fabricated IDTs of different finger numbers (n = 25, 40, 50, and 80) and lengths (L = 100/130/170/200 μm) for three different thicknesses of ZnO films (200, 600, and 800 nm). The measured Q factor confirms that reducing the length and the number of IDT fingers enables us to reach better electrical performances at resonant frequencies around 700 MHz. The extracted results for an optimized micro-resonator device having an IDT length of 100 μm and 40 finger electrodes show a Q of 1180 and a kt2 of 7.4%. We demonstrate also that the reduction of the ZnO thickness from 800 nm to 200 nm increases the quality factor from 430 to 1600, respectively, around 700 MHz. Experimental data are in very good agreement with theoretical simulations of the fabricated devices
Integration of Resonant Coil for Wireless Power Transfer and Implantable Antenna for Signal Transfer
Directory of Open Access Journals (Sweden)
Dong-Wook Seo
2016-01-01
Full Text Available We propose the integration of the resonant coil for wireless power transfer (WPT and the implantable antenna for physiological signal transfer. The integration allows for a compact biomedical implantable system such as electrocardiogram (ECG recorder and pacemaker. While the resonant coils resonate at the frequency of 13.56 MHz for the WPT, the implantable antenna works in the medical implant communications service (MICS band of 402–405 MHz for wireless communications. They share the narrow substrate area of a bar-type shape; the coil has the current path on the outer part of the substrate and the meandered planar inverted-F antenna (PIFA occupies the inside of the coil. To verify the potentials of the proposed structure, a prototype is fabricated and tested in vitro. The power transfer efficiency (PTE of about 20% is obtained at a distance of 15 mm and the antenna gain of roughly −40 dBi is achieved.
Integrated nanohole array surface plasmon resonance sensing device using a dual-wavelength source
International Nuclear Information System (INIS)
Escobedo, C; Vincent, S; Choudhury, A I K; Campbell, J; Gordon, R; Brolo, A G; Sinton, D
2011-01-01
In this paper, we demonstrate a compact integrated nanohole array-based surface plasmon resonance sensing device. The unit includes a LED light source, driving circuitry, CCD detector, microfluidic network and computer interface, all assembled from readily available commercial components. A dual-wavelength LED scheme was implemented to increase spectral diversity and isolate intensity variations to be expected in the field. The prototype shows bulk sensitivity of 266 pixel intensity units/RIU and a limit of detection of 6 × 10 −4 RIU. Surface binding tests were performed, demonstrating functionality as a surface-based sensing system. This work is particularly relevant for low-cost point-of-care applications, especially those involving multiple tests and field studies. While nanohole arrays have been applied to many sensing applications, and their suitability to device integration is well established, this is the first demonstration of a fully integrated nanohole array-based sensing device.
Farrar, Danielle; Budson, Andrew E
2017-04-01
While the relationship between diffusion tensor imaging (DTI) measurements and training effects is explored by Voelker et al. (this issue), a cursory discussion of functional magnetic resonance imaging (fMRI) measurements categorizes increased activation with findings of greater white matter integrity. Evidence of the relationship between fMRI activation and white matter integrity is conflicting, as is the relationship between fMRI activation and training effects. An examination of the changes in fMRI activation in response to training is helpful, but the relationship between DTI and fMRI activation, particularly in the context of white matter changes, must be examined further before general conclusions can be drawn.
Wu, Yaw-Dong; Shih, Tien-Tsorng; Lee, Jian-Jang
2009-11-01
In this paper, we proposed the design of directional coupler integrated with ring resonator based on two-dimensional photonic crystals (2D PCs) to develop a triplexer filter. It can be widely used as the fiber access network element for multiplexer-demultiplexer wavelength selective in fiber-to-the-home (FTTH) communication systems. The directional coupler is chosen to separate the wavelengths of 1490nm and 1310nm. The ring resonator separates the wavelength of 1550nm. The transmission efficiency is larger than 90%. Besides, the total size of propose triplexer is only 19μm×12μm. We present simulation results using the finite-difference time-domain (FDTD) method for the proposed structure.
Indian Academy of Sciences (India)
small bar magnets. NMR spectroscopy .... that the integrated area for the methylene .... in a network of spins. .... Schematic representation of the type of short (broken arrows) and medium-range .... we can define between cities and towns in the.
Nonlinear Dynamics of Silicon Nanowire Resonator Considering Nonlocal Effect.
Jin, Leisheng; Li, Lijie
2017-12-01
In this work, nonlinear dynamics of silicon nanowire resonator considering nonlocal effect has been investigated. For the first time, dynamical parameters (e.g., resonant frequency, Duffing coefficient, and the damping ratio) that directly influence the nonlinear dynamics of the nanostructure have been derived. Subsequently, by calculating their response with the varied nonlocal coefficient, it is unveiled that the nonlocal effect makes more obvious impacts at the starting range (from zero to a small value), while the impact of nonlocal effect becomes weaker when the nonlocal term reaches to a certain threshold value. Furthermore, to characterize the role played by nonlocal effect in exerting influence on nonlinear behaviors such as bifurcation and chaos (typical phenomena in nonlinear dynamics of nanoscale devices), we have calculated the Lyapunov exponents and bifurcation diagram with and without nonlocal effect, and results shows the nonlocal effect causes the most significant effect as the device is at resonance. This work advances the development of nanowire resonators that are working beyond linear regime.
Chaos-induced resonant effects and its control
International Nuclear Information System (INIS)
Zambrano, Samuel; Casado, Jose M.; Sanjuan, Miguel A.F.
2007-01-01
This Letter shows that a suitable chaotic signal can induce resonant effects analogous to those observed in presence of noise in a bistable system under periodic forcing. By constructing groups of chaotic and random perturbations with similar one-time statistics we show that in some cases chaos and noise induce indistinguishable resonant effects. This reinforces the conjecture by which in some situations where noise is supposed to play a key role maybe chaos is the key ingredient. Here we also show that the presence of a chaotic signal as the perturbation leading to a resonance opens new control perspectives based on our ability to stabilize chaos in different periodic orbits. A discussion of the possible implications of these facts is also presented at the end of the Letter
Resonant nuclear battery may aid in mitigating the greenhouse effect
International Nuclear Information System (INIS)
Brown, P.M.
1989-01-01
A new process for the direct conversion of radioactive decay energy directly into electricity of a usable form is currently being developed by Peripheral Systems, Inc. of Portland, Oregon. United States Patent 4,835,433 was issued May 30, 1989 to protect this Resonant Nuclear Power Supply. When developed, this system promises cheap, reliable power from a package small and light enough to be mobile and an energy density great enough for use as a space-based power supply. One of the potential domestic applications could be to power electric automobiles. Use in highly populated areas would have a tremendous beneficial effect on the ecology. The principle of operation for the resonant nuclear power supply is an LCR (inductance capacitance resistance) resonant tank circuit oscillating at its self-resonant frequency (at resonance, the inductive reactance and the capacitive reactance cancel to leave the ohmic resistance of the circuit as the only major loss of energy). A means for absorbing the natural radioactive decay energy emitted from an alpha or beta source is provided in the primary tank circuit and contributes an amount of energy, by means of the beta voltaic effect, in excess of the energy required to sustain the oscillation of the LCR primary tank. A transformer is impedance matched to this oscillating primary circuit for efficient energy transfer of the excess energy to a secondary output circuit, which yields net electrical power in a high-frequency usable form to drive a load
The temperature coefficient of the resonance integral for uranium metal and oxide
Energy Technology Data Exchange (ETDEWEB)
Blomberg, P; Hellstrand, E; Homer, S
1960-06-15
The temperature coefficient of the resonance integral in uranium metal and oxide has been measured over a wide temperature range for rods with three different diameters. The results for metal agree with most earlier results from activation measurements but differ as much as a factor of two from results obtained with reactivity methods. For oxide only one measurement has been reported recently. Our value is considerably lower than the result of that measurement. The experiments will continue in order to find the reason for the large discrepancy mentioned above.
The temperature coefficient of the resonance integral for uranium metal and oxide
International Nuclear Information System (INIS)
Blomberg, P.; Hellstrand, E.; Homer, S.
1960-06-01
The temperature coefficient of the resonance integral in uranium metal and oxide has been measured over a wide temperature range for rods with three different diameters. The results for metal agree with most earlier results from activation measurements but differ as much as a factor of two from results obtained with reactivity methods. For oxide only one measurement has been reported recently. Our value is considerably lower than the result of that measurement. The experiments will continue in order to find the reason for the large discrepancy mentioned above
Conformally integrated stent cell resonators for wireless monitoring of peripheral artery disease
Viswanath, Anupam
2013-01-01
This paper presents the design and in vitro evaluation of magnetoelastic sensors intended for wireless monitoring of tissue accumulation in peripheral artery stents. The sensors, shaped like stent cells, are fabricated from 28-μm thick foils of magnetoelastic Ni-Fe alloy and are conformally integrated with the stent. The typical sensitivity to viscosity is 427 ppm/cP over a 1.1-8.6 cP range. The sensitivity to mass loading is typically 63,000-65000 ppm/mg with resonant frequency showing an 8.1% reduction for an applied mass that is 15% of the unloaded mass of the sensor. © 2013 IEEE.
Directional effects in transitional resonance spectra and group constants
International Nuclear Information System (INIS)
Hill, R.N.; Oh, K.O.; Rhodes, J.D.
1989-01-01
Analytical exploratory investigations indicate that transition effects such as streaming cause a considerable spatial variation in the neutron spectra across resonances; streaming leads to opposite effects in the forward and backward directions. The neglect of this coupled spatial/angular variations of the transitory resonance spectra is an approximation that is common to all current group constant generation methodologies. This paper presents a description of the spatial/angular coupling of the neutron flux across isolated resonances. It appears to be necessary to differentiate between forward-and backward-directed neutron flux components or even to consider components in narrower angular cones. The effects are illustrated for an isolated actinide resonance in a simplified fast reactor blanket problem. The resonance spectra of the directional flux components φ + and φ - , and even more so the 90-deg cone components, are shown to deviate significantly from the infinite medium approximation, and the differences increase with penetration. The charges in φ + lead to a decreasing scattering group constant that enhances neutron transmission; the changes in φ - lead to an increasing group constant inhibiting backward scattering. Therefore, the changes in the forward-and backward-directed spectra both lead to increased neutron transmission. Conversely, the flux (φ = φ + +φ - ) is shown to agree closely with the infinite medium approximation both in the analytical formulas and in the numerical solution. The directional effect cancel in the summation. The forward-and backward-directed flux components are used as weighting spectra to illustrate the group constant changes for a single resonance
Indian Academy of Sciences (India)
Administrator
Refresher Course in. Experimental Physics. Refresher Course on. Advanced in Biophysics. IISc Young Science. Fellowship Programme. Inside Back Cover. Flowering Trees. (Credit: K Sankara Rao,IISc,. Bangalore). 97. 83. Classics. REFLECTIONS. 71 Integrative Microbiology – The Third Golden Age. Moselio Schaechter.
Nonlinear resonance islands and modulational effects in a proton synchrotron
International Nuclear Information System (INIS)
Satogata, T.J.
1993-01-01
The authors examine one-dimensional and two-dimensional nonlinear resonance islands created in the transverse phase space of a proton synchrotron by nonlinear magnets. The authors examine application of the theoretical framework constructed to the phenomenon of modulational diffusion in a collider model of the Fermilab Tevatron. For the one-dimensional resonance island system, the authors examine the effects of two types of modulational perturbations on the stability of these resonance islands: Tune modulation and beta function modulation. Hamiltonian models are presented which predict stability boundaries that depend on only three parameters: The strength and frequency of the modulation and the frequency of small oscillations inside the resonance island. The tune modulation model is successfully tested in experiment, where frequency domain analysis coupled with tune modulation is demonstrated to be useful in measuring the strength of a nonlinear resonance. Nonlinear resonance islands are examined in two transverse dimensions in the presence of coupling and linearly independent crossing resonances. The authors present a first-order Hamiltonian model which predicts fixed point locations, but does not reproduce small oscillation frequencies seen in tracking. Particle tracking is presented which shows evidence of two-dimensional persistent signals, and the authors make suggestions on methods for observing such signals in future experiment. The authors apply the tune modulation stability diagram to the explicitly two-dimensional phenomenon of modulational diffusion in the Fermilab Tevatron with beam-beam kicks as the source of nonlinearity. The amplitude growth created by this mechanism in simulation is exponential rather than root-time as predicted by modulational diffusion models. The authors comment upon the luminosity and lifetime limitations such a mechanism implies in a proton storage ring
Directory of Open Access Journals (Sweden)
Weipeng Yang
2017-10-01
Full Text Available An integral plus resonant sliding mode direct power control (IRSMC DPC strategy for voltage source converter high voltage direct current (VSC-HVDC systems under unbalanced grid voltage conditions is proposed in this paper. Through detailed instantaneous power flow analysis, a generalized power compensation method, by which the ratio between the amplitude of active and reactive power ripples can be controlled continuously, is obtained. This enables the system to provide flexible power control, so that the desired performance of the system on both the ac and dc sides can be attained under different operating conditions. When the grid voltage is unbalanced, one or both of the active and reactive power terms contain ripples, oscillating at twice the grid frequency, to obtain non-distorted ac current. A power controller consisting of the proportional, integral and resonant control laws is designed using the sliding mode control approach, to achieve accurate power control objective. Simulation studies on a two-terminal VSC-HVDC system using MATLAB/SIMULINK (R2013b, Mathworks, Natick, MA, USA are conducted to verify the effectiveness of the IRSMC DPC strategy. The results show that this strategy ensures satisfactory performance of the system over a wide range of operating conditions.
1 million-Q optomechanical microdisk resonators for sensing with very large scale integration
Hermouet, M.; Sansa, M.; Banniard, L.; Fafin, A.; Gely, M.; Allain, P. E.; Santos, E. Gil; Favero, I.; Alava, T.; Jourdan, G.; Hentz, S.
2018-02-01
Cavity optomechanics have become a promising route towards the development of ultrasensitive sensors for a wide range of applications including mass, chemical and biological sensing. In this study, we demonstrate the potential of Very Large Scale Integration (VLSI) with state-of-the-art low-loss performance silicon optomechanical microdisks for sensing applications. We report microdisks exhibiting optical Whispering Gallery Modes (WGM) with 1 million quality factors, yielding high displacement sensitivity and strong coupling between optical WGMs and in-plane mechanical Radial Breathing Modes (RBM). Such high-Q microdisks with mechanical resonance frequencies in the 102 MHz range were fabricated on 200 mm wafers with Variable Shape Electron Beam lithography. Benefiting from ultrasensitive readout, their Brownian motion could be resolved with good Signal-to-Noise ratio at ambient pressure, as well as in liquid, despite high frequency operation and large fluidic damping: the mechanical quality factor reduced from few 103 in air to 10's in liquid, and the mechanical resonance frequency shifted down by a few percent. Proceeding one step further, we performed an all-optical operation of the resonators in air using a pump-probe scheme. Our results show our VLSI process is a viable approach for the next generation of sensors operating in vacuum, gas or liquid phase.
Surface and temperature effects in isovector giant resonances
International Nuclear Information System (INIS)
Lipparini, E.; Stringari, S.
1988-01-01
Using the liquid droplet model (LDM) we investigate three different sum rules for the isovector dipole and monopole excitations. Analytical formulae are derived for the excitation energies of these resonances and the predictions are compared with experiments. The role of the surface and the effects of temperature are explicitly discussed. (orig.)
Effective Hamiltonians in quantum physics: resonances and geometric phase
International Nuclear Information System (INIS)
Rau, A R P; Uskov, D
2006-01-01
Effective Hamiltonians are often used in quantum physics, both in time-dependent and time-independent contexts. Analogies are drawn between the two usages, the discussion framed particularly for the geometric phase of a time-dependent Hamiltonian and for resonances as stationary states of a time-independent Hamiltonian
Effect of magnetic resonance imaging characteristics on uterine fibroid treatment
Directory of Open Access Journals (Sweden)
Duc NM
2018-04-01
Full Text Available Nguyen Minh Duc, Huynh Quang HuyDepartment of Radiology, Pham Ngoc Thach University of Medicine, Ho Chi Minh City, VietnamAbstract: Uterine fibroids are the most common gynecological benign tumors adversely affecting the quality of life of women of a reproductive age. Magnetic resonance imaging (MRI is efficient at localizing the site of lesions and characterizing uterine fibroids before treatment. Understanding the different characteristics of uterine fibroids on MRI is essential, because it not only enables prompt diagnosis, but also guides the development of suitable therapeutic methods. This pictorial review demonstrates the effect of MRI features on uterine fibroid treatment. Keywords: uterine fibroids, characteristics, magnetic resonance imaging, treatments
Tunneling effect in cavity-resonator-coupled arrays
International Nuclear Information System (INIS)
Ma Hua; Xu Zhuo; Qu Shao-Bo; Zhang Jie-Qiu; Wang Jia-Fu; Liang Chang-Hong
2013-01-01
The quantum tunneling effect (QTE) in a cavity-resonator-coupled (CRC) array was analytically and numerically investigated. The underlying mechanism was interpreted by treating electromagnetic waves as photons, and then was generalized to acoustic waves and matter waves. It is indicated that for the three kinds of waves, the QTE can be excited by cavity resonance in a CRC array, resulting in sub-wavelength transparency through the narrow splits between cavities. This opens up opportunities for designing new types of crystals based on CRC arrays, which may find potential applications such as quantum devices, micro-optic transmission, and acoustic manipulation. (condensed matter: electronic structure, electrical, magnetic, and optical properties)
Photonic crystal ring resonator based optical filters for photonic integrated circuits
International Nuclear Information System (INIS)
Robinson, S.
2014-01-01
In this paper, a two Dimensional (2D) Photonic Crystal Ring Resonator (PCRR) based optical Filters namely Add Drop Filter, Bandpass Filter, and Bandstop Filter are designed for Photonic Integrated Circuits (PICs). The normalized output response of the filters is obtained using 2D Finite Difference Time Domain (FDTD) method and the band diagram of periodic and non-periodic structure is attained by Plane Wave Expansion (PWE) method. The size of the device is minimized from a scale of few tens of millimeters to the order of micrometers. The overall size of the filters is around 11.4 μm × 11.4 μm which is highly suitable of photonic integrated circuits
Micro-resonators based on integrated polymer technology for optical sensing
Girault, Pauline; Lemaitre, Jonathan; Guendouz, Mohammed; Lorrain, Nathalie; Poffo, Luiz; Gadonna, Michel; Bosc, Dominique
2014-05-01
Research on sensors has experienced a noticeable development over the last decades especially in label free optical biosensors. However, compact sensors without markers for rapid, reliable and inexpensive detection of various substances induce a significant research of new technological solutions. The context of this work is the development of a sensor based on easily integrated and inexpensive micro-resonator (MR) component in integrated optics, highly sensitive and selective mainly in the areas of health and food. In this work, we take advantage of our previous studies on filters based on micro-resonators (MR) to experiment a new couple of polymers in the objective to use MR as a sensing function. MRs have been fabricated by processing SU8 polymer as core and PMATRIFE polymer as cladding layer of the waveguide. The refractive index contrast reaches 0.16 @ 1550 nm. Sub-micronic ring waveguides gaps from 0.5 to 1 μm have been successfully achieved with UV (i-line) photolithography. This work confirms our forecasts, published earlier, about the resolution that can be achieved. First results show a good extinction coefficient of ~17 dB, a quality factor around 104 and a finesse of 12. These results are in concordance with the theoretical study and they allow us to validate our technology with this couple of polymers. Work is going on with others lower cladding materials that will be used to further increase refractive index contrast for sensing applications.
Douaud, Gwenaëlle; Filippini, Nicola; Knight, Steven; Talbot, Kevin; Turner, Martin R
2011-12-01
Amyotrophic lateral sclerosis as a system failure is a concept supported by the finding of consistent extramotor as well as motor cerebral pathology. The functional correlates of the structural changes detected using advanced magnetic resonance imaging techniques such as diffusion tensor imaging and voxel-based morphometry have not been extensively studied. A group of 25 patients with amyotrophic lateral sclerosis was compared to healthy control subjects using a multi-modal neuroimaging approach comprising T(1)-weighted, diffusion-weighted and resting-state functional magnetic resonance imaging. Using probabilistic tractography, a grey matter connection network was defined based upon the prominent corticospinal tract and corpus callosum involvement demonstrated by white matter tract-based spatial statistics. This 'amyotrophic lateral sclerosis-specific' network included motor, premotor and supplementary motor cortices, pars opercularis and motor-related thalamic nuclei. A novel analysis protocol, using this disease-specific grey matter network as an input for a dual-regression analysis, was then used to assess changes in functional connectivity directly associated with this network. A spatial pattern of increased functional connectivity spanning sensorimotor, premotor, prefrontal and thalamic regions was found. A composite of structural and functional magnetic resonance imaging measures also allowed the qualitative discrimination of patients from controls. An integrated structural and functional connectivity approach therefore identified apparently dichotomous processes characterizing the amyotrophic lateral sclerosis cerebral network failure, in which there was increased functional connectivity within regions of decreased structural connectivity. Patients with slower rates of disease progression showed connectivity measures with values closer to healthy controls, raising the possibility that functional connectivity increases might not simply represent a
Energy Technology Data Exchange (ETDEWEB)
Haeggblom, H
1969-02-15
In order to investigate some aspects of the 'Intermediate Resonance Approximation' developed by Goldstein and Cohen, comparative calculations have been made using this method together with more accurate methods. The latter are as follows: a) For homogeneous materials the slowing down equation is solved in the fundamental mode approximation with the computer programme SPENG. All cross sections are given point by point. Because the spectrum can be calculated for at most 2000 energy points, the energy regions where the resonances are accurately described are limited. Isolated resonances in the region 100 to 240 eV are studied for {sup 238}U/Fe and {sup 238}U/Fe/Na mixtures. In the regions 161 to 251 eV and 701 to 1000 eV, mixtures of {sup 238}U and Na are investigated. {sup 239}Pu/Na and {sup 239}Pu/{sup 238}U/Na mixtures are studied in the region 161 to 251 eV. b) For heterogeneous compositions in slab geometry the integral transport equation is solved using the FLIS programme in 22 energy groups. Thus, only one resonance can be considered in each calculation. Two resonances are considered, namely those belonging to {sup 238}U at 190 and 937 eV. The compositions are lattices of {sup 238}U and Fe plates. The computer programme DORIX is used for the calculations using the Intermediate Resonance Approximation. Calculations of reaction rates and effective cross sections are made at 0, 300 and 1100 deg K for homogeneous media and at 300 deg K for heterogeneous media. The results are compared to those obtained by using the programmes SPENG and FLIS and using the narrow resonance approximation.
International Nuclear Information System (INIS)
Rouben, D.C.
1997-01-01
A semiclassical method for resonant tunneling in a quantum well in the presence of a magnetic field tilted with regard to an electric field is developed. In particular a semiclassical formula is derived for the total current of electrons after the second barrier of the quantum well. The contribution of the stable and unstable orbits is studied. It appears that the parameters which describe the classical chaos in the quantum well have an important effect on the tunneling current. A numerical experiment is led, the contributions to the current of some particular orbits are evaluated and the results are compared with those given by the quantum theory. (A.C.)
Mode splitting effect in FEMs with oversized Bragg resonators
Energy Technology Data Exchange (ETDEWEB)
Peskov, N. Yu.; Sergeev, A. S. [Institute of Applied Physics Russian Academy of Sciences, Nizhny Novgorod (Russian Federation); Kaminsky, A. K.; Perelstein, E. A.; Sedykh, S. N. [Joint Institute for Nuclear Research, Dubna (Russian Federation); Kuzikov, S. V. [Institute of Applied Physics Russian Academy of Sciences, Nizhny Novgorod (Russian Federation); Nizhegorodsky State University, Nizhny Novgorod (Russian Federation)
2016-07-15
Splitting of the fundamental mode in an oversized Bragg resonator with a step of the corrugation phase, which operates over the feedback loop involving the waveguide waves of different transverse structures, was found to be the result of mutual influence of the neighboring zones of the Bragg scattering. Theoretical description of this effect was developed within the framework of the advanced (four-wave) coupled-wave approach. It is shown that mode splitting reduces the selective properties, restricts the output power, and decreases the stability of the narrow-band operating regime in the free-electron maser (FEM) oscillators based on such resonators. The results of the theoretical analysis were confirmed by 3D simulations and “cold” microwave tests. Experimental data on Bragg resonators with different parameters in a 30-GHz FEM are presented. The possibility of reducing the mode splitting by profiling the corrugation parameters is shown. The use of the mode splitting effect for the output power enhancement by passive compression of the double-frequency pulse generated in the FEM with such a resonator is discussed.
A few words about resonances in the electroweak effective Lagrangian
Energy Technology Data Exchange (ETDEWEB)
Rosell, Ignasi [Departamento de Ciencias Físicas, Matemáticas y de la Computación, Universidad CEU Cardenal Herrera, c/ Sant Bartomeu 55, 46115 Alfara del Patriarca, València (Spain); Pich, Antonio; Santos, Joaquín [Departament de Física Teòrica, IFIC, Universitat de València – CSIC, Apt. Correus 22085, 46071 València (Spain); Sanz-Cillero, Juan José [Departamento de Física Teórica and Instituto Física Teórica, IFT-UAM/CSIC, Universidad Autónoma de Madrid, Cantoblanco, 28049 Madrid (Spain)
2016-01-22
Contrary to a widely spread believe, we have demonstrated that strongly coupled electroweak models including both a light Higgs-like boson and massive spin-1 resonances are not in conflict with experimental constraints on the oblique S and T parameters. We use an effective Lagrangian implementing the chiral symmetry breaking SU (2){sub L} ⊗ SU (2){sub R} → SU (2){sub L+R} that contains the Standard Model gauge bosons coupled to the electroweak Goldstones, one Higgs-like scalar state h with mass m{sub h} = 126 GeV and the lightest vector and axial-vector resonance multiplets V and A. We have considered the one-loop calculation of S and T in order to study the viability of these strongly-coupled scenarios, being short-distance constraints and dispersive relations the main ingredients of the calculation. Once we have constrained the resonance parameters, we do a first approach to the determination of the low energy constants of the electroweak effective theory at low energies (without resonances). We show this determination in the case of the purely Higgsless bosonic Lagrangian.
Shi, Yifei
2013-08-01
Internal resonant modes are always observed in the marching-on-in-time (MOT) solution of the time domain electric field integral equation (EFIE), although \\'relaxed initial conditions,\\' which are enforced at the beginning of time marching, should in theory prevent these spurious modes from appearing. It has been conjectured that, numerical errors built up during time marching establish the necessary initial conditions and induce the internal resonant modes. However, this conjecture has never been proved by systematic numerical experiments. Our numerical results in this communication demonstrate that, the internal resonant modes\\' amplitudes are indeed dictated by the numerical errors. Additionally, it is shown that in a few cases, the internal resonant modes can be made \\'invisible\\' by significantly suppressing the numerical errors. These tests prove the conjecture that the internal resonant modes are induced by numerical errors when the time domain EFIE is solved by the MOT method. © 2013 IEEE.
Shi, Yifei; Bagci, Hakan; Lu, Mingyu
2013-01-01
Internal resonant modes are always observed in the marching-on-in-time (MOT) solution of the time domain electric field integral equation (EFIE), although 'relaxed initial conditions,' which are enforced at the beginning of time marching, should in theory prevent these spurious modes from appearing. It has been conjectured that, numerical errors built up during time marching establish the necessary initial conditions and induce the internal resonant modes. However, this conjecture has never been proved by systematic numerical experiments. Our numerical results in this communication demonstrate that, the internal resonant modes' amplitudes are indeed dictated by the numerical errors. Additionally, it is shown that in a few cases, the internal resonant modes can be made 'invisible' by significantly suppressing the numerical errors. These tests prove the conjecture that the internal resonant modes are induced by numerical errors when the time domain EFIE is solved by the MOT method. © 2013 IEEE.
Temperature Dependence of the Resonant Magnetoelectric Effect in Layered Heterostructures
Directory of Open Access Journals (Sweden)
Dmitrii A. Burdin
2017-10-01
Full Text Available The dependence of the resonant direct magnetoelectric effect on temperature is studied experimentally in planar composite structures. Samples of rectangular shapes with dimensions of 5 mm × 20 mm employed ferromagnetic layers of either an amorphous (metallic glass alloy or nickel with a thickness of 20–200 μm and piezoelectric layers of single crystalline langatate material or lead zirconate titanate piezoelectric ceramics with a thickness of 500 μm. The temperature of the samples was varied in a range between 120 and 390 K by blowing a gaseous nitrogen stream around them. It is shown that the effective characteristics of the magnetoelectric effect—such as the mechanical resonance frequency fr, the quality factor Q and the magnitude of the magnetoelectric coefficient αE at the resonance frequency—are contingent on temperature. The interrelations between the temperature changes of the characteristics of the magnetoelectric effect and the temperature variations of the following material parameters—Young’s modulus Y, the acoustic quality factor of individual layers, the dielectric constant ε, the piezoelectric modulus d of the piezoelectric layer as well as the piezomagnetic coefficients λ(n of the ferromagnetic layer—are established. The effect of temperature on the characteristics of the nonlinear magnetoelectric effect is observed for the first time. The results can be useful for designing magnetoelectric heterostructures with specified temperature characteristics, in particular, for the development of thermally stabilized magnetoelectric devices.
Resonant scattering on impurities in the quantum Hall effect
International Nuclear Information System (INIS)
Gurvitz, A.
1994-06-01
We developed a new approach to carrier transport between the edge states via resonant scattering on impurities, which is applicable both for short and long range impurities. A detailed analysis of resonant scattering on a single impurity is performed. The results used for study of the inter-edge transport by multiple resonant hopping via different impurities' site. We found the total conductance can be obtained from an effective Schroedinger equation with constant diagonal matrix elements in the Hamiltonian, where the complex non-diagonal matrix elements are the amplitudes of a carrier hopping between different impurities. It is explicitly shown how the complex phase leads to Aharonov-Bohm oscillations in the total conductance. Neglecting the contribution of self-crossing resonant-percolation trajectories, we found that the inter-edge carrier transport is similar to propagation in one-dimensional system with off-diagonal disorder. Then we demonstrated that each Landau band has an extended state Ε Ν , while all other states are localized, and the localization length behaves as L - 1 Ν (Ε) ∼ (Ε - Ε Ν ) 2 . (author)
Zhenmin Chen; Xiang Wu; Liying Liu; Lei Xu
2017-01-01
In this work, we present a novel approach for obtaining the effective mass of mechanical vibration mode in micro-bubble resonators (MBRs). To be specific, the effective mass is deduced from the measurement of optical spring effect (OSE) in MBRs. This approach is demonstrated and applied to analyze the effective mass of hollow MBRs and liquid-filled MBRs, respectively. It is found that the liquid-filled MBRs has significantly stronger OSE and a less effective mass than hollow MBRs, both of the...
RF slice profile effects in magnetic resonance fingerprinting.
Hong, Taehwa; Han, Dongyeob; Kim, Min-Oh; Kim, Dong-Hyun
2017-09-01
The radio frequency (RF) slice profile effects on T1 and T2 estimation in magnetic resonance fingerprinting (MRF) are investigated with respect to time-bandwidth product (TBW), flip angle (FA) level and field inhomogeneities. Signal evolutions are generated incorporating the non-ideal slice selective excitation process using Bloch simulation and matched to the original dictionary with and without the non-ideal slice profile taken into account. For validation, phantom and in vivo experiments are performed at 3T. Both simulations and experiments results show that T1 and T2 error from non-ideal slice profile increases with increasing FA level, off-resonance, and low TBW values. Therefore, RF slice profile effects should be compensated for accurate determination of the MR parameters. Copyright © 2017 Elsevier Inc. All rights reserved.
A Faraday effect position sensor for interventional magnetic resonance imaging.
Bock, M; Umathum, R; Sikora, J; Brenner, S; Aguor, E N; Semmler, W
2006-02-21
An optical sensor is presented which determines the position and one degree of orientation within a magnetic resonance tomograph. The sensor utilizes the Faraday effect to measure the local magnetic field, which is modulated by switching additional linear magnetic fields, the gradients. Existing methods for instrument localization during an interventional MR procedure often use electrically conducting structures at the instruments that can heat up excessively during MRI and are thus a significant danger for the patient. The proposed optical Faraday effect position sensor consists of non-magnetic and electrically non-conducting components only so that heating is avoided and the sensor could be applied safely even within the human body. With a non-magnetic prototype set-up, experiments were performed to demonstrate the possibility of measuring both the localization and the orientation in a magnetic resonance tomograph. In a 30 mT m(-1) gradient field, a localization uncertainty of 1.5 cm could be achieved.
Crowe, Iain F; Clark, Nicholas; Hussein, Siham; Towlson, Brian; Whittaker, Eric; Milosevic, Milan M; Gardes, Frederic Y; Mashanovich, Goran Z; Halsall, Matthew P; Vijayaraghaven, Aravind
2014-07-28
We examine the near-IR light-matter interaction for graphene integrated cavity ring resonators based on silicon-on-insulator (SOI) race-track waveguides. Fitting of the cavity resonances from quasi-TE mode transmission spectra reveal the real part of the effective refractive index for graphene, n(eff) = 2.23 ± 0.02 and linear absorption coefficient, α(gTE) = 0.11 ± 0.01dBμm(-1). The evanescent nature of the guided mode coupling to graphene at resonance depends strongly on the height of the graphene above the cavity, which places limits on the cavity length for optical sensing applications.
E2 nuclear resonance effects in pionic and kaonic atoms
International Nuclear Information System (INIS)
Batty, C.J.; Biagi, S.F.; Blecher, M.
1977-09-01
The attenuation due to the E2 nuclear resonance effect has been measured in hadronic atoms using pions with 111 Cd and 112 Cd, and for kaons with 122 Sn. Energies of the relevant X-ray and γ-ray transitions and of the X-ray cascade intensities have also been measured so as to give a self-consistent set of information. The results are found to be in very good agreement with theoretical calculations. (author)
Behavioral and Biological Effects of Resonant Electromagnetic Absorption in Rats.
1976-11-01
for 23-550 MHz, biological phantom materials to simulate tissue properties, monopole -above-ground radiation chamber, design of a waveguide slot array...Resonant Electromagnetic Power Absorption in Rats" L T OF FTCTIF S A,’L i .LIS SFigure Pa 1 A photograiph of the monopole -above-gruund radiation...and mice without ground effects (L/2b = 3.25 where 21Tb is the "average" circumference of the animals) ........ .................... ... 20 8
The effect of compressibility on the Alfven spatial resonance heating
International Nuclear Information System (INIS)
Azevedo, C.A.
1984-01-01
The effect of compressibility of magnetic field line on the damping rate of Alfven spatial resonance heating for a high beta plasma (Kinetic pressure/magnetic pressure) was analysed, using the ideal MHD (Magnetohydrodynamic) model in cylindrical geometry for a diffuse θ-pinch with conducting wall. The dispersion relation was obtained solving the equation of motion in the plasma and vacuum regions together with boundary conditions. (Author) [pt
DEFF Research Database (Denmark)
Freijedo Fernandez, Francisco Daniel; Chaudhary, Sanjay Kumar; Guerrero, Josep M.
2015-01-01
-domain. As an alternative, a power based averaged modelling is also proposed. Type IV wind turbine harmonic signature and STATCOM active harmonic mitigation are considered for the simulation case studies. Simulation results provide a good insight of the features and limitations of the proposed methodologies.......This paper approaches modelling methodologies for integration of wind turbines and STATCOM in harmonic resonance studies. Firstly, an admittance equivalent model representing the harmonic signature of grid connected voltage source converters is provided. A simplified type IV wind turbine modelling...... is then straightforward. This linear modelling is suitable to represent the wind turbine in the range of frequencies at which harmonic interactions are likely. Even the admittance method is suitable both for frequency and time domain studies, some limitations arise in practice when implementing it in the time...
Thermal neutron capture cross sections resonance integrals and g-factors
International Nuclear Information System (INIS)
Mughabghab, S.F.
2003-02-01
The thermal radiative capture cross sections and resonance integrals of elements and isotopes with atomic numbers from 1 to 83 (as well as 232 Th and 238 U) have been re-evaluated by taking into consideration all known pertinent data published since 1979. This work has been undertaken as part of an IAEA co-ordinated research project on 'Prompt capture gamma-ray activation analysis'. Westcott g-factors for radiative capture cross sections at a temperature of 300K were computed by utilizing the INTER code and ENDF-B/VI (Release 8) library files. The temperature dependence of the Westcott g-factor is illustrated for 113 Cd, 124 Xe and 157 Gd at temperatures of 150, 294 and 400K. Comparisons have also been made of the newly evaluated capture cross sections of 6 Li, 7 Li, 12 C and 207 Pb with those determined by the k 0 method. (author)
Detection of Moving Targets Using Soliton Resonance Effect
Kulikov, Igor K.; Zak, Michail
2013-01-01
The objective of this research was to develop a fundamentally new method for detecting hidden moving targets within noisy and cluttered data-streams using a novel "soliton resonance" effect in nonlinear dynamical systems. The technique uses an inhomogeneous Korteweg de Vries (KdV) equation containing moving-target information. Solution of the KdV equation will describe a soliton propagating with the same kinematic characteristics as the target. The approach uses the time-dependent data stream obtained with a sensor in form of the "forcing function," which is incorporated in an inhomogeneous KdV equation. When a hidden moving target (which in many ways resembles a soliton) encounters the natural "probe" soliton solution of the KdV equation, a strong resonance phenomenon results that makes the location and motion of the target apparent. Soliton resonance method will amplify the moving target signal, suppressing the noise. The method will be a very effective tool for locating and identifying diverse, highly dynamic targets with ill-defined characteristics in a noisy environment. The soliton resonance method for the detection of moving targets was developed in one and two dimensions. Computer simulations proved that the method could be used for detection of singe point-like targets moving with constant velocities and accelerations in 1D and along straight lines or curved trajectories in 2D. The method also allows estimation of the kinematic characteristics of moving targets, and reconstruction of target trajectories in 2D. The method could be very effective for target detection in the presence of clutter and for the case of target obscurations.
Effects of lymphatic drainage on cellulitis assessed by magnetic resonance
International Nuclear Information System (INIS)
Meyer, Patricia Froes; Martins, Nara Mendes; Martins, Flavia Mendes; Monteiro, Rosimary Araujo; Mendonca, Karla Morganna Pereira Pinto de
2008-01-01
The aim of this study was to assess the use of magnetic resonance as a new method for evaluating the manual lymphatic drainage technique in treating cellulitis. Cellulitis is one of the main esthetic problems that lead women toward seeking guidance and specific treatments. There are various therapeutic approaches, owing to the multifactorial nature of its pathogen, although the effectiveness of most of these has not been definitively proven, given that the assessment methods used are mostly subjective or do not provide enough information on subcutaneous tissue. The introduction of magnetic resonance as a means of assessing a lymphatic drainage technique in cellulitis treatment makes the evaluation more accurate, since it enables a detailed study of subcutaneous architecture. (author)
Effects of lymphatic drainage on cellulitis assessed by magnetic resonance
Energy Technology Data Exchange (ETDEWEB)
Meyer, Patricia Froes; Martins, Nara Mendes; Martins, Flavia Mendes; Monteiro, Rosimary Araujo; Mendonca, Karla Morganna Pereira Pinto de [Universidade Federal do Rio Grande do Norte (UFRN), Natal, RN (Brazil). Centro de Ciencias da Saude
2008-12-15
The aim of this study was to assess the use of magnetic resonance as a new method for evaluating the manual lymphatic drainage technique in treating cellulitis. Cellulitis is one of the main esthetic problems that lead women toward seeking guidance and specific treatments. There are various therapeutic approaches, owing to the multifactorial nature of its pathogen, although the effectiveness of most of these has not been definitively proven, given that the assessment methods used are mostly subjective or do not provide enough information on subcutaneous tissue. The introduction of magnetic resonance as a means of assessing a lymphatic drainage technique in cellulitis treatment makes the evaluation more accurate, since it enables a detailed study of subcutaneous architecture. (author)
Energy Technology Data Exchange (ETDEWEB)
Slipicevic, K [Institute of Nuclear Sciences Boris Kidric, Vinca, Beograd (Yugoslavia)
1968-07-01
Following a review of the existing theories od resonance absorption this thesis includes a new approach for calculating the effective resonance integral of absorbed neutrons, new approximate formula for the penetration factor, an analysis of the effective resonance integral and the correction of the resonance integral taking into account the interference of potential and resonance dissipation. A separate chapter is devoted to calculation of the effective resonance integral for the regular reactor lattice with cylindrical fuel elements.
Energy Technology Data Exchange (ETDEWEB)
Keating, Kristina [Rutgers Univ., Newark, NJ (United States). Dept. of Earth and Environmental Sciences; Slater, Lee [Rutgers Univ., Newark, NJ (United States). Dept. of Earth and Environmental Sciences; Ntarlagiannis, Dimitris [Rutgers Univ., Newark, NJ (United States). Dept. of Earth and Environmental Sciences; Williams, Kenneth H. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Earth Sciences Division
2015-02-24
This documents contains the final report for the project "Integrated Geophysical Measurements for Bioremediation Monitoring: Combining Spectral Induced Polarization, Nuclear Magnetic Resonance and Magnetic Methods" (DE-SC0007049) Executive Summary: Our research aimed to develop borehole measurement techniques capable of monitoring subsurface processes, such as changes in pore geometry and iron/sulfur geochemistry, associated with remediation of heavy metals and radionuclides. Previous work has demonstrated that geophysical method spectral induced polarization (SIP) can be used to assess subsurface contaminant remediation; however, SIP signals can be generated from multiple sources limiting their interpretation value. Integrating multiple geophysical methods, such as nuclear magnetic resonance (NMR) and magnetic susceptibility (MS), with SIP, could reduce the ambiguity of interpretation that might result from a single method. Our research efforts entails combining measurements from these methods, each sensitive to different mineral forms and/or mineral-fluid interfaces, providing better constraints on changes in subsurface biogeochemical processes and pore geometries significantly improving our understanding of processes impacting contaminant remediation. The Rifle Integrated Field Research Challenge (IFRC) site was used as a test location for our measurements. The Rifle IFRC site is located at a former uranium ore-processing facility in Rifle, Colorado. Leachate from spent mill tailings has resulted in residual uranium contamination of both groundwater and sediments within the local aquifer. Studies at the site include an ongoing acetate amendment strategy, native microbial populations are stimulated by introduction of carbon intended to alter redox conditions and immobilize uranium. To test the geophysical methods in the field, NMR and MS logging measurements were collected before, during, and after acetate amendment. Next, laboratory NMR, MS, and SIP measurements
Nonthermal effects of therapeutic ultrasound: the frequency resonance hypothesis.
Johns, Lennart D
2002-07-01
To present the frequency resonance hypothesis, a possible mechanical mechanism by which treatment with non-thermal levels of ultrasound stimulates therapeutic effects. The review encompasses a 4-decade history but focuses on recent reports describing the effects of nonthermal therapeutic levels of ultrasound at the cellular and molecular levels. A search of MEDLINE from 1965 through 2000 using the terms ultrasound and therapeutic ultrasound. The literature provides a number of examples in which exposure of cells to therapeutic ultrasound under nonthermal conditions modified cellular functions. Nonthermal levels of ultrasound are reported to modulate membrane properties, alter cellular proliferation, and produce increases in proteins associated with inflammation and injury repair. Combined, these data suggest that nonthermal effects of therapeutic ultrasound can modify the inflammatory response. The concept of the absorption of ultrasonic energy by enzymatic proteins leading to changes in the enzymes activity is not novel. However, recent reports demonstrating that ultrasound affects enzyme activity and possibly gene regulation provide sufficient data to present a probable molecular mechanism of ultrasound's nonthermal therapeutic action. The frequency resonance hypothesis describes 2 possible biological mechanisms that may alter protein function as a result of the absorption of ultrasonic energy. First, absorption of mechanical energy by a protein may produce a transient conformational shift (modifying the 3-dimensional structure) and alter the protein's functional activity. Second, the resonance or shearing properties of the wave (or both) may dissociate a multimolecular complex, thereby disrupting the complex's function. This review focuses on recent studies that have reported cellular and molecular effects of therapeutic ultrasound and presents a mechanical mechanism that may lead to a better understanding of how the nonthermal effects of ultrasound may be
Theory of inelastic effects in resonant atom-surface scattering
International Nuclear Information System (INIS)
Evans, D.K.
1983-01-01
The progress of theoretical and experimental developments in atom-surface scattering is briefly reviewed. The formal theory of atom-surface resonant scattering is reviewed and expanded, with both S and T matrix approaches being explained. The two-potential formalism is shown to be useful for dealing with the problem in question. A detailed theory based on the S-matrix and the two-potential formalism is presented. This theory takes account of interactions between the incident atoms and the surface phonons, with resonant effects being displayed explicitly. The Debye-Waller attenuation is also studied. The case in which the atom-surface potential is divided into an attractive part V/sub a/ and a repulsive part V/sub r/ is considered at length. Several techniques are presented for handling the scattering due to V/sub r/, for the case in which V/sub r/ is taken to be the hard corrugated surface potential. The theory is used to calculate the scattered intensities for the system 4 He/LiF(001). A detailed comparison with experiment is made, with polar scans, azimuthal scans, and time-of-flight measurements being considered. The theory is seen to explain the location and signature of resonant features, and to provide reasonable overall agreement with the experimental results
Liu, Yongjing; Li, Xinxin; Zhang, Zhixiang; Zuo, Guomin; Cheng, Zhenxing; Yu, Haitao
2009-02-01
Nanogram per milliliter-level ultra-low concentration detection of alpha-fetoprotein (AFP), which is an important marker for heptocellular carcinoma, is in favor of early-stage prognosis and disease diagnosis. On-the-spot rapid detection of such antigens as AFP highly requires innovative micro/nano techniques. To meet this requirement, an advanced resonant microcantilever is developed and used for screening the tumor marker at nanogram per milliliter level. The sensing principle of the resonant microcantilever is measuring frequency-shift versus specific-adsorbed mass. With both electromagnetic resonance-exciting and piezoresistive readout elements on-chip integrated, the microcantilever sensor is operated in a rotating resonance mode to improve sensitivity and resolution to specific mass adsorption. Prior to detection of AFP with previously immobilized anti-AFP antibody, the antigen-antibody specific-binding is confirmed with an enzyme linked immunosorbent assay experiment. By implementing the specific reaction in liquid and reading out the sensor signal in lab air environment, the micromechanical sensor has achieved the sensitive scale between 2 and 20 ng/ml. To effectively depress cross-talk signal and improve resolution, the insensitive regions of the cantilever surface are pre-modified with 2-[methoxy (polyethyleneoxy) propyl] trimethoxysilane for nonspecific bio-adsorption minimization. Finally, a better AFP detecting limit than 2 ng/mL is experimentally achieved. The label-free resonant microcantilever sensor is promising in low-cost or even disposable early-stage prognosis and diagnosis of tumors.
Uranus, H.P.; Zhuang, L.; Roeloffzen, C.G.H.; Hoekstra, Hugo
We report experimental observations of the negative-group-velocity (v_g) phenomenon in an integrated-optical two-port ring-resonator circuit. We demonstrate that when the v_g is negative, the (main) peak of output pulse appears earlier than the peak of a reference pulse, while for a positive v_g,
Resonant spin Hall effect in two dimensional electron gas
Shen, Shun-Qing
2005-03-01
Remarkable phenomena have been observed in 2DEG over last two decades, most notably, the discovery of integer and fractional quantum Hall effect. The study of spin transport provides a good opportunity to explore spin physics in two-dimensional electron gas (2DEG) with spin-orbit coupling and other interaction. It is already known that the spin-orbit coupling leads to a zero-field spin splitting, and competes with the Zeeman spin splitting if the system is subjected to a magnetic field perpendicular to the plane of 2DEG. The result can be detected as beating of the Shubnikov-de Haas oscillation. Very recently the speaker and his collaborators studied transport properties of a two-dimensional electron system with Rashba spin-orbit coupling in a perpendicular magnetic field. The spin-orbit coupling competes with the Zeeman splitting to generate additional degeneracies between different Landau levels at certain magnetic fields. It is predicted theoretically that this degeneracy, if occurring at the Fermi level, gives rise to a resonant spin Hall conductance, whose height is divergent as 1/T and whose weight is divergent as -lnT at low temperatures. The charge Hall conductance changes by 2e^2/h instead of e^2/h as the magnetic field changes through the resonant point. The speaker will address the resonance condition, symmetries in the spin-orbit coupling, the singularity of magnetic susceptibility, nonlinear electric field effect, the edge effect and the disorder effect due to impurities. This work was supported by the Research Grants Council of Hong Kong under Grant No.: HKU 7088/01P. *S. Q. Shen, M. Ma, X. C. Xie, and F. C. Zhang, Phys. Rev. Lett. 92, 256603 (2004) *S. Q. Shen, Y. J. Bao, M. Ma, X. C. Xie, and F. C. Zhang, cond-mat/0410169
Uncertainty Analysis with Considering Resonance Self-shielding Effect
International Nuclear Information System (INIS)
Han, Tae Young
2016-01-01
If infinitely diluted multi-group cross sections were used for the sensitivity, the covariance data from the evaluated nuclear data library (ENDL) was directly applied. However, in case of using a self-shielded multi-group cross section, the covariance data should be corrected considering self-shielding effect. Usually, implicit uncertainty can be defined as the uncertainty change by the resonance self-shielding effect as described above. MUSAD ( Modules of Uncertainty and Sensitivity Analysis for DeCART ) has been developed for a multiplication factor and cross section uncertainty based on the generalized perturbation theory and it, however, can only quantify the explicit uncertainty by the self-shielded multi-group cross sections without considering the implicit effect. Thus, this paper addresses the implementation of the implicit uncertainty analysis module into the code and the numerical results for the verification are provided. The implicit uncertainty analysis module has been implemented into MUSAD based on infinitely-diluted cross section-based consistent method. The verification calculation was performed on MHTGR 350 Ex.I-1a and the differences with McCARD result decrease from 40% to 1% in CZP case and 3% in HFP case. From this study, it is expected that MUSAD code can reasonably produce the complete uncertainty on VHTR or LWR where the resonance self-shielding effect should be significantly considered
Uncertainty Analysis with Considering Resonance Self-shielding Effect
Energy Technology Data Exchange (ETDEWEB)
Han, Tae Young [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)
2016-10-15
If infinitely diluted multi-group cross sections were used for the sensitivity, the covariance data from the evaluated nuclear data library (ENDL) was directly applied. However, in case of using a self-shielded multi-group cross section, the covariance data should be corrected considering self-shielding effect. Usually, implicit uncertainty can be defined as the uncertainty change by the resonance self-shielding effect as described above. MUSAD ( Modules of Uncertainty and Sensitivity Analysis for DeCART ) has been developed for a multiplication factor and cross section uncertainty based on the generalized perturbation theory and it, however, can only quantify the explicit uncertainty by the self-shielded multi-group cross sections without considering the implicit effect. Thus, this paper addresses the implementation of the implicit uncertainty analysis module into the code and the numerical results for the verification are provided. The implicit uncertainty analysis module has been implemented into MUSAD based on infinitely-diluted cross section-based consistent method. The verification calculation was performed on MHTGR 350 Ex.I-1a and the differences with McCARD result decrease from 40% to 1% in CZP case and 3% in HFP case. From this study, it is expected that MUSAD code can reasonably produce the complete uncertainty on VHTR or LWR where the resonance self-shielding effect should be significantly considered.
Directory of Open Access Journals (Sweden)
Jiawei eWANG
2015-04-01
Full Text Available Silicon nitride (SiN is a promising material platform for integrating photonic components and microfluidic channels on a chip for label-free, optical biochemical sensing applications in the visible to near-infrared wavelengths. The chip-scale SiN-based optofluidic sensors can be compact due to a relatively high refractive index contrast between SiN and the fluidic medium, and low-cost due to the complementary metal-oxide-semiconductor (CMOS-compatible fabrication process. Here, we demonstrate SiN-based integrated optofluidic biochemical sensors using a coupled-resonator optical waveguide (CROW in the visible wavelengths. The working principle is based on imaging in the far field the out-of-plane elastic-light-scattering patterns of the CROW sensor at a fixed probe wavelength. We correlate the imaged pattern with reference patterns at the CROW eigenstates. Our sensing algorithm maps the correlation coefficients of the imaged pattern with a library of calibrated correlation coefficients to extract a minute change in the cladding refractive index. Given a calibrated CROW, our sensing mechanism in the spatial domain only requires a fixed-wavelength laser in the visible wavelengths as a light source, with the probe wavelength located within the CROW transmission band, and a silicon digital charge-coupled device (CCD / CMOS camera for recording the light scattering patterns. This is in sharp contrast with the conventional optical microcavity-based sensing methods that impose a strict requirement of spectral alignment with a high-quality cavity resonance using a wavelength-tunable laser. Our experimental results using a SiN CROW sensor with eight coupled microrings in the 680nm wavelength reveal a cladding refractive index change of ~1.3 × 10^-4 refractive index unit (RIU, with an average sensitivity of ~281 ± 271 RIU-1 and a noise-equivalent detection limit (NEDL of 1.8 ×10^-8 RIU ~ 1.0 ×10^-4 RIU across the CROW bandwidth of ~1 nm.
Moessbauer effect and electron paramagnetic resonance studies on yeast aconitase
International Nuclear Information System (INIS)
Suzuki, Takashi; Maeda, Yutaka; Sakai, Hiroshi; Fujimoto, Shigeru; Morita, Yuhei.
1975-01-01
The Moessbauer effect and electron paramagnetic resonance (EPR) of yeast aconitase [EC 4.2.1.3] purified from the cells of Candida lipolytica (ATCC 20114) were measured. Moessbauer spectra suggested that yeast acontitase mostly contained two high-spin Fe(III) ions in an antiferromagnetically coupled binuclear complex that resembled oxidized 2 Fe ferredoxins, together with a small amount of high-spin Fe(II). EPR spectra recorded no signal at 77 0 K, but showed a slightly asymmetric signal centered at g=2.0 at 4.2 0 K, presumably due to the small amount of Fe(II) Fe(III) pairs. (auth.)
Energy Technology Data Exchange (ETDEWEB)
Ferdinand, Benedikt; Wiedmaier, Dominik; Koelle, Dieter; Kleiner, Reinhold [Physikalisches Institut and Center for Quantum Science in LISA+, Universitaet Tuebingen (Germany); Bothner, Daniel [Physikalisches Institut and Center for Quantum Science in LISA+, Universitaet Tuebingen (Germany); Kavli Institute of Nanoscience, Delft University of Technology, Delft (Netherlands)
2016-07-01
We intend to investigate a hybrid quantum system where ultracold atomic gases play the role of a long-living quantum memory, coupled to a superconducting qubit via a coplanar waveguide transmission line resonator. As a first step we developed a resonator chip containing a Z-shaped trapping wire for the atom trap. In order to suppress parasitic resonances due to stray capacitances, and to achieve good ground connection we use hybrid superconductor - normal conductor chips. As an additional degree of freedom we add a ferroelectric capacitor making the resonators voltage-tunable. We furthermore show theoretical results on the expected coupling strength between resonator and atomic cloud.
Homogenized boundary conditions and resonance effects in Faraday cages
Hewett, D. P.; Hewitt, I. J.
2016-05-01
We present a mathematical study of two-dimensional electrostatic and electromagnetic shielding by a cage of conducting wires (the so-called `Faraday cage effect'). Taking the limit as the number of wires in the cage tends to infinity, we use the asymptotic method of multiple scales to derive continuum models for the shielding, involving homogenized boundary conditions on an effective cage boundary. We show how the resulting models depend on key cage parameters such as the size and shape of the wires, and, in the electromagnetic case, on the frequency and polarization of the incident field. In the electromagnetic case, there are resonance effects, whereby at frequencies close to the natural frequencies of the equivalent solid shell, the presence of the cage actually amplifies the incident field, rather than shielding it. By appropriately modifying the continuum model, we calculate the modified resonant frequencies, and their associated peak amplitudes. We discuss applications to radiation containment in microwave ovens and acoustic scattering by perforated shells.
Zhang, Hao; Kang, Wei; Wu, Wen
2017-12-01
In this paper, a miniaturized diplexer designed with two novel one-third-mode substrate integrated resonator (OTMSIR) filters has been presented. The one-third triangular resonator cavity with two transmission zeros (TZs) and two transmission poles is investigated. TZs are implemented by taking cross couplings of lower order modes in this design. The diplexer is then obtained by integrating two different sizes of OTMSIR filters with a common T-junction structure. A X-band diplexer operating at 10 GHz and 11.5 GHz is designed on a substrate with a dielectric constant of 3.55 to verify the above design concept. This novel structure features more compact size, better transmission performance, higher out of band rejection and easier integration compared with other circuits. A good agreement is obtained between the simulations and the measured results.
Directory of Open Access Journals (Sweden)
Zhenmin Chen
2017-09-01
Full Text Available In this work, we present a novel approach for obtaining the effective mass of mechanical vibration mode in micro-bubble resonators (MBRs. To be specific, the effective mass is deduced from the measurement of optical spring effect (OSE in MBRs. This approach is demonstrated and applied to analyze the effective mass of hollow MBRs and liquid-filled MBRs, respectively. It is found that the liquid-filled MBRs has significantly stronger OSE and a less effective mass than hollow MBRs, both of the extraordinary behaviors can be beneficial for applications such as mass sensing. Larger OSE from higher order harmonics of the mechanical modes is also observed. Our work paves a way towards the developing of OSE-based high sensitive mass sensor in MBRs.
Chen, Zhenmin; Wu, Xiang; Liu, Liying; Xu, Lei
2017-09-30
In this work, we present a novel approach for obtaining the effective mass of mechanical vibration mode in micro-bubble resonators (MBRs). To be specific, the effective mass is deduced from the measurement of optical spring effect (OSE) in MBRs. This approach is demonstrated and applied to analyze the effective mass of hollow MBRs and liquid-filled MBRs, respectively. It is found that the liquid-filled MBRs has significantly stronger OSE and a less effective mass than hollow MBRs, both of the extraordinary behaviors can be beneficial for applications such as mass sensing. Larger OSE from higher order harmonics of the mechanical modes is also observed. Our work paves a way towards the developing of OSE-based high sensitive mass sensor in MBRs.
Integrated Optic Surface Plasmon Resonance Measurements in a Borosilicate Glass Substrate
Directory of Open Access Journals (Sweden)
Antonino Parisi
2008-11-01
Full Text Available The surface plasmon resonance (SPR technique is a well-known optical method that can be used to measure the refractive index of organic nano-layers adsorbed on a thin metal film. Although there are many configurations for measuring biomolecular interactions, SPR-based techniques play a central role in many current biosensing experiments, since they are the most suited for sensitive and quantitative kinetic measurements. Here we give some results from the analysis and numerical elaboration of SPR data from integrated optics experiments in a particular borosilicate glass, chosen for its composition offering the rather low refractive index of 1.4701 at 633 nm wavelength. These data regard the flow over the sensing region (metal window of different solutions with refractive indexes in the range of interest (1.3ÃƒÂ·1.5 for the detection of contaminants in aqueous solutions. After a discussion of the principles of SPR, of the metal window design optimization by means of optical interaction numerical modeling, and of waveguide fabrication techniques, we give a description of system setup and experimental results. Optimum gold film window thickness and width in this guided-wave configuration has been for the first time derived and implemented on an integrated optic prototype device. Its characterization is given by means of the real time waveguide output intensity measurements, which correspond to the interaction between the sensing gold thin film window and the flowing analyte. The SPR curve was subsequently inferred. Finally, a modified version of the device is reported, with channel waveguides arranged in a Y-junction optical circuit, so that laser source stability requirements are lowered by a factor of 85 dB, making possible the use of low cost sources in practical applications.
QCD and resonance physics Nonperturbative effects in operator expansion
International Nuclear Information System (INIS)
Shifman, M.A.; Vainshtein, A.L.; Zakharov, V.I.
1978-01-01
The aim of the paper is to show that QCD provides well-defined predictions for a single resonance. The crucial point is the inclusion of power corrections to asymptotic freedom which are due to nonperturbative effects of QCD. Apart from presenting a general outline in intuitive terms the operator expansion for the product of external currents is discussed. It is argued that the effect of nonperturbative terms is twofold: a) they induce vacuum expectation values such as (0.1Gsub(μv)sup(a)Gsub(μv)sup(a)10), Gsub(μv)sup(a) being the gluon field strength tensor and b) they break the operator expansion itself starting from some critical dimension. The latter effect is suppressed as a high power of Q -2 where Q is the momentum carried by a current. Both a) and b) are examplified in the instanton physics but the whole approach is of more general value
Post irradiation effects (PIE) in integrated circuits
International Nuclear Information System (INIS)
Barnes, C.E.; Shaw, D.C.; Fleetwood, D.M.; Winokur, P.S.
1992-01-01
Post Irradiation Effects (PIE) ranging from normal recovery catastrophic failure have been observed in integrated circuits during the PIE period. These variations indicate that a rebound or PIE recipe used for radiation hardness assurance must be chosen with care. In this paper, the authors provide examples of PIE in a variety of integrated circuits of importance to spacecraft electronics
Impact of Treatment Integrity on Intervention Effectiveness
Fryling, Mitch J.; Wallace, Michele D.; Yassine, Jordan N.
2012-01-01
Treatment integrity has cogent implications for intervention effectiveness. Understanding these implications is an important, but often neglected, undertaking in behavior analysis. This paper reviews current research on treatment integrity in applied behavior analysis. Specifically, we review research evaluating the relation between integrity…
Homogenized boundary conditions and resonance effects in Faraday cages
Hewitt, I. J.
2016-01-01
We present a mathematical study of two-dimensional electrostatic and electromagnetic shielding by a cage of conducting wires (the so-called ‘Faraday cage effect’). Taking the limit as the number of wires in the cage tends to infinity, we use the asymptotic method of multiple scales to derive continuum models for the shielding, involving homogenized boundary conditions on an effective cage boundary. We show how the resulting models depend on key cage parameters such as the size and shape of the wires, and, in the electromagnetic case, on the frequency and polarization of the incident field. In the electromagnetic case, there are resonance effects, whereby at frequencies close to the natural frequencies of the equivalent solid shell, the presence of the cage actually amplifies the incident field, rather than shielding it. By appropriately modifying the continuum model, we calculate the modified resonant frequencies, and their associated peak amplitudes. We discuss applications to radiation containment in microwave ovens and acoustic scattering by perforated shells. PMID:27279775
Bioceramic Resonance Effect on Meridian Channels: A Pilot Study
Directory of Open Access Journals (Sweden)
Ting-Kai Leung
2015-01-01
Full Text Available Bioceramic is a kind of material which emits nonionizing radiation and luminescence, induced by visible light. Bioceramic also facilitates the breakup of large clusters of water molecules by weakening hydrogen bonds. Hydrogen bond weakening, which allows water molecules to act in diverse ways under different conditions, is one of the key mechanisms underlying the effects of Bioceramic on biophysical and physical-chemical processes. Herein, we used sound to amplify the effect of Bioceramic and further developed an experimental device for use in humans. Thirteen patients who suffered from various chronic and acute illnesses that severely affected their sleep patterns and life quality were enrolled in a trial of Bioceramic resonance (i.e., rhythmic 100-dB sound waves with frequency set at 10 Hz applied to the skin surface of the anterior chest. According to preliminary data, a “Propagated Sensation along Meridians” (PSM was experienced in all Bioceramic resonance-treated patients but not in any of the nine control patients. The device was believed to enhance microcirculation through a series of biomolecular and physiological processes and to subject the specific meridian channels of Traditional Chinese Medicine (TCM to coherent vibration. This noninvasive technique may offer an alternative to needle acupuncture and other traditional medical practices with clinical benefits.
Directory of Open Access Journals (Sweden)
Dileep Kumar Varma Sagiraju
2017-08-01
Full Text Available The load voltage and frequency should be controlled under steady state and transient conditions in off grid applications. Power quality and power management is very important task for rural communities under erratic wind and load conditions. This paper presents a coordinated Proportional resonant (PR and battery energy controller for enhancement of power quality and power management in direct drive standalone wind energy system. The dynamic performance of standalone direct drive Permanent Magnet Synchronous Generator (PMSG is investigated with the proposed control scheme under various operating conditions such as fluctuating wind with step increase and decrease in wind velocity, balanced and unbalanced load conditions. The proposed PR control strategy with battery energy controller also ensures effective power balance between wind and battery source in order to fulfill the load demand. The superiority of the proposed control strategy is confirmed by comparing with the traditional vector control strategy under fluctuating wind and load conditions through MATLAB/SIMULINK platform.
Evaluation of thermal effects on the beam quality of disk laser with unstable resonator
Shayganmanesh, Mahdi; Beirami, Reza
2017-01-01
In this paper thermal effects of the disk active medium and associated effects on the beam quality of laser are investigated. Using Collins integral and iterative method, transverse mode of an unstable resonator including a Yb:YAG active medium in disk geometry is calculated. After that the beam quality of the laser is calculated based on the generalized beam characterization method. Thermal lensing of the disk is calculated based on the OPD (Optical Path Difference) concept. Five factors influencing the OPD including temperature gradient, disk thermal expansion, photo-elastic effect, electronic lens and disk deformation are considered in our calculations. The calculations show that the effect of disk deformation factor on the quality of laser beam in the resonator is strong. However the total effect of all the thermal factors on the internal beam quality is fewer. Also it is shown that thermal effects degrade the output power, beam profile and beam quality of the output laser beam severely. As well the magnitude of each of affecting factors is evaluated distinctly.
Simulation of electron spin resonance spectroscopy in diverse environments: An integrated approach
Zerbetto, Mirco; Polimeno, Antonino; Barone, Vincenzo
2009-12-01
We discuss in this work a new software tool, named E-SpiReS (Electron Spin Resonance Simulations), aimed at the interpretation of dynamical properties of molecules in fluids from electron spin resonance (ESR) measurements. The code implements an integrated computational approach (ICA) for the calculation of relevant molecular properties that are needed in order to obtain spectral lines. The protocol encompasses information from atomistic level (quantum mechanical) to coarse grained level (hydrodynamical), and evaluates ESR spectra for rigid or flexible single or multi-labeled paramagnetic molecules in isotropic and ordered phases, based on a numerical solution of a stochastic Liouville equation. E-SpiReS automatically interfaces all the computational methodologies scheduled in the ICA in a way completely transparent for the user, who controls the whole calculation flow via a graphical interface. Parallelized algorithms are employed in order to allow running on calculation clusters, and a web applet Java has been developed with which it is possible to work from any operating system, avoiding the problems of recompilation. E-SpiReS has been used in the study of a number of different systems and two relevant cases are reported to underline the promising applicability of the ICA to complex systems and the importance of similar software tools in handling a laborious protocol. Program summaryProgram title: E-SpiReS Catalogue identifier: AEEM_v1_0 Program summary URL:http://cpc.cs.qub.ac.uk/summaries/AEEM_v1_0.html Program obtainable from: CPC Program Library, Queen's University, Belfast, N. Ireland Licensing provisions: GPL v2.0 No. of lines in distributed program, including test data, etc.: 311 761 No. of bytes in distributed program, including test data, etc.: 10 039 531 Distribution format: tar.gz Programming language: C (core programs) and Java (graphical interface) Computer: PC and Macintosh Operating system: Unix and Windows Has the code been vectorized or
Effect of inflation on parametric resonance during preheating
International Nuclear Information System (INIS)
Hirai, Shiro
2002-01-01
The effect of inflation on parametric resonance during preheating is investigated. The behaviour of the preheating scalar field during inflation is investigated and is found to become squeezed in cases ranging from small-scale cases to large-scale cases. However, the positive-frequency solution is usually adopted in the initial condition of the scalar field at preheating. Although large squeezing occurs during inflation, the difference in the comoving occupation number of particles n k between two initial conditions is shown to be not so large. Rather, the ratio n k varies from 0.2 to 5.0, depending on k. In order to clarify this situation, we introduce the squeeze formulation. The squeeze parameters r and φ are calculated not only in preheating, but also in inflation. Since the squeeze parameters are calculated from inflation to preheating, we can clarify the behaviour of the parametric resonance. In preheating, the behaviour of r is shown to remain relatively unchanged with respect to k; however, the squeeze angle φ displays different behaviour for large-scale cases and small-scale cases
Effects of Aperture Size on Q factor and Shielding Effectiveness of a Cubic Resonator
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S. Parr
2017-09-01
Full Text Available The EMC properties of a cubic metallic shield are highly affected by its resonances. At the resonant frequencies, the shielding effectiveness (SE collapses, which results in high field strengths inside the cavity. This can cause failure or even breakdown of electronic devices inside the shield. The resonant behaviour is mainly determined by the quality or Q factor of the shield. In this paper, the effects of the aperture size on the Q factor and the SE of an electrically large, cubic shield are analysed. At first, a method is developed in order to determine the Q factor based on the resonance behaviour of the shield in time domain. Only the first resonance of the shield is considered therefore. The results are evaluated for different aperture diameters and compared with theory for the Q factor. The dominant coupling mechanism of electromagnetic energy into the shield is thus identified. Then the effect of aperture size on the SE is analysed. The excitation of resonances is very probable if the interfering signal is an ultrawideband (UWB pulse, which constitutes a typical intentional electromagnetic interference (IEMI scenario. Therefore, the relation between aperture size and SE is analysed using the theory of the transient SE for a broadband signal with a constant spectral density distribution. The results show, that a worst case aperture size exists, where the SE has its minimum.
Heterogeneous Economic Integration Agreement Effects
Baier, Scott L.; Bergstrand, Jeffrey H.; Clance, Matthew W.
2015-01-01
Gravity equations have been used for more than 50 years to estimate ex post the partial effects of trade costs on international trade flows, and the well-known - and traditionally presumed exogenous â€“ "trade-cost elasticity" plays a central role in computing general equilibrium trade-flow and welfare effects of trade-cost changes. This paper addresses theoretically and empirically the influence of variable and fixed export costs in explaining the likely heterogeneity in the trade-cost elast...
International Nuclear Information System (INIS)
McLellan, G.W.
1994-01-01
This integrated test plan describes the demonstration test of the ResonantSonic drilling system. This demonstration is part of the Office of Technology Development's Volatile Organic Compound Arid Integrated Demonstration (VOC-Arid ID). Two main purposes of this demonstration are (1) to continue testing the ResonantSonic drilling system compatibility with the Hanford Site waste characterization programs, and (2) to transfer this method for use at the Hanford Site, other government sites, and the private sector. The ResonantSonic method is a dry drilling technique. Field testing of this method began in July 1993. During the next four months, nine holes were drilled, and continuous core samples were retrieved. Penetration rates were 2 to 3 times the baseline, and the operational downtime rate was less than 10%. Successfully demonstrated equipment refinements included a prototype 300 series ResonantSonic head, a new drill rod design for 18-centimeter diameter pipe, and an automated pipe handling system. Various configurations of sampling equipment and drill bits were tested, depending on geologic conditions. The principal objective of the VOC-Arid ID is to determine the viability of emerging technologies that can be used to characterize, remediate, and/or monitor arid or semiarid sites containing VOCs (e.g., carbon tetrachloride) with or without associated metal and radionuclide contamination
Interference effect in the resonant emission of a semiconductor microcavity
Cassabois, G.; Bogani, F.; Triques, A. L.; Delalande, C.; Roussignol, Ph.
2001-07-01
We present a phenomenological description of the coherent emission from a semiconductor microcavity in the strong-coupling regime. We consider two main contributions which are calculated in the framework of the semiclassical approach of the linear dispersion theory: reflectivity corresponds to the response of a uniform microcavity while resonant Rayleigh scattering (RRS) arises from disorder. Our simulations are compared to experimental results obtained at normal incidence in a backscattering geometry by means of cw spectroscopy and interferometric correlation with subpicosecond resolution. In this geometry, a fair agreement is reached assuming interferences between the two aforementioned contributions. This interference effect gives evidence of the drastic modification of the RRS emission pattern of the embedded quantum well induced by the Fabry-Pérot cavity.
Effects of Colored Noise on Stochastic Resonance in Sensory Neurons
International Nuclear Information System (INIS)
Nozaki, D.; Mar, D.J.; Collins, J.J.; Grigg, P.
1999-01-01
Noise can assist neurons in the detection of weak signals via a mechanism known as stochastic resonance (SR). We demonstrate experimentally that SR-type effects can be obtained in rat sensory neurons with white noise, 1/f noise, or 1/f 2 noise. For low-frequency input noise, we show that the optimal noise intensity is the lowest and the output signal-to-noise ratio the highest for conventional white noise. We also show that under certain circumstances, 1/f noise can be better than white noise for enhancing the response of a neuron to a weak signal. We present a theory to account for these results and discuss the biological implications of 1/f noise. copyright 1999 The American Physical Society
Directory of Open Access Journals (Sweden)
Paolo Bardella
2016-01-01
Full Text Available In the last few decades, various solutions have been proposed to increase the modulation bandwidth and, consequently, the transmission bit-rate of semiconductor lasers. In this manuscript, we discuss a design procedure for a recently proposed laser cavity realized with the monolithic integration of two distributed Bragg reflector (DBR lasers allowing one to extend the modulation bandwidth. Such an extension is obtained introducing in the dynamic response a photon-photon resonance (PPR at a frequency higher than the modulation bandwidth of the corresponding single-section laser. Design guidelines will be proposed, and dynamic small and large signal simulations results, calculated using a finite difference traveling wave (FDTW numerical simulator, will be discussed to confirm the design results. The effectiveness of the design procedure is verified in a structure with PPR frequency at 35 GHz allowing one to obtain an open eye diagram for a non-return-to-zero (NRZ digital signal up to 80 GHz . Furthermore, the investigation of the rich dynamics of this structure shows that with proper bias conditions, it is possible to obtain also a tunable self-pulsating signal in a frequency range related to the PPR design.
Yakubov, Vladislav; Xu, Lirong; Volinsky, Alex A.; Qiao, Lijie; Pan, De'an
2017-08-01
Trilayer Ni/PZT/Ni cylindrical magnetoelectric (ME) composites were prepared by electrodeposition, a process, which creates sub-millimeter raised edges due to current concentration near sharp points. The ME response in both axial and vertical modes was measured with the edges, with only outer edges removed, and with both outer and inner edges removed. The ME voltage coefficient improved at resonance by 40% and 147% without the edges in the vertical and axial modes, respectively. The observed improvements in three different samples were only present at the ME resonance and no changes were detected outside of the ME resonance. Mechanical quality factor at resonance also improved with no effect on the resonant frequency. Experimentally demonstrated minor geometry changes resulted in substantial ME improvement at resonant frequency. This study demonstrates device performance optimization. The observed effects have been attributed to improved vibrations in terms of decreased damping coefficient and enhanced vibration amplitude at resonance.
Directory of Open Access Journals (Sweden)
Vladislav Yakubov
2017-08-01
Full Text Available Trilayer Ni/PZT/Ni cylindrical magnetoelectric (ME composites were prepared by electrodeposition, a process, which creates sub-millimeter raised edges due to current concentration near sharp points. The ME response in both axial and vertical modes was measured with the edges, with only outer edges removed, and with both outer and inner edges removed. The ME voltage coefficient improved at resonance by 40% and 147% without the edges in the vertical and axial modes, respectively. The observed improvements in three different samples were only present at the ME resonance and no changes were detected outside of the ME resonance. Mechanical quality factor at resonance also improved with no effect on the resonant frequency. Experimentally demonstrated minor geometry changes resulted in substantial ME improvement at resonant frequency. This study demonstrates device performance optimization. The observed effects have been attributed to improved vibrations in terms of decreased damping coefficient and enhanced vibration amplitude at resonance.
International Nuclear Information System (INIS)
Bora, B.; Bhuyan, H.; Favre, M.; Wyndham, E.; Chuaqui, H.
2012-01-01
Plasma series resonance (PSR) effect is well known in geometrically asymmetric capacitively couple radio frequency plasma. However, plasma series resonance effect in geometrically symmetric plasma has not been properly investigated. In this work, a theoretical approach is made to investigate the plasma series resonance effect and its influence on Ohmic and stochastic heating in geometrically symmetric discharge. Electrical asymmetry effect by means of dual frequency voltage waveform is applied to excite the plasma series resonance. The results show considerable variation in heating with phase difference between the voltage waveforms, which may be applicable in controlling the plasma parameters in such plasma.
Self-shielding effect in unresolved resonance data in JENDL-4.0
International Nuclear Information System (INIS)
Konno, Chikara; Takakura, Kosuke; Ochiai, Kentaro; Sato, Satoshi; Kato, Yoshinari
2012-01-01
At International Conference on Nuclear Data for Science and Technology in 2007 we pointed out that most of unresolved resonance data in JENDL-3.3 have a problem related to self-shielding correction. Here with a simple calculation model we have investigated whether the latest JENDL, JENDL-4.0, was improved for the problem or not. The results suggest that unresolved resonance data in JENDL-4.0 have no problem, but it seems that self-shielding effects for the unresolved resonance data in JENDL-4.0 are too large. New benchmark experiments for unresolved resonance data are strongly recommended in order to verify unresolved resonance data. (author)
Effects of stress on nursing integrity.
McIntosh, Bryan; Sheppy, Bruce
This article looks at the relationship between stress, nursing integrity and patient care. It has been argued that the professional integrity of nurses has been eroded and consequently they have become more susceptible to anxiety, stress and exhaustion, potentially affecting care delivery. The authors suggest that the goal of providing high professional standards is threatened by increased service demands, and there is therefore a need for nurses to develop effective coping strategies to manage stress resulting from competing tensions in the workplace.
Effects of water on fingernail electron paramagnetic resonance dosimetry.
Zhang, Tengda; Zhao, Zhixin; Zhang, Haiying; Zhai, Hezheng; Ruan, Shuzhou; Jiao, Ling; Zhang, Wenyi
2016-09-01
Electron paramagnetic resonance (EPR) is a promising biodosimetric method, and fingernails are sensitive biomaterials to ionizing radiation. Therefore, kinetic energy released per unit mass (kerma) can be estimated by measuring the level of free radicals within fingernails, using EPR. However, to date this dosimetry has been deficient and insufficiently accurate. In the sampling processes and measurements, water plays a significant role. This paper discusses many effects of water on fingernail EPR dosimetry, including disturbance to EPR measurements and two different effects on the production of free radicals. Water that is unable to contact free radicals can promote the production of free radicals due to indirect ionizing effects. Therefore, varying water content within fingernails can lead to varying growth rates in the free radical concentration after irradiation-these two variables have a linear relationship, with a slope of 1.8143. Thus, EPR dosimetry needs to be adjusted according to the water content of the fingernails of an individual. When the free radicals are exposed to water, the eliminating effect will appear. Therefore, soaking fingernail pieces in water before irradiation, as many researchers have previously done, can cause estimation errors. In addition, nails need to be dehydrated before making accurately quantitative EPR measurements. © The Author 2016. Published by Oxford University Press on behalf of The Japan Radiation Research Society and Japanese Society for Radiation Oncology.
Trade Integration Effects in ASEAN Countries
Directory of Open Access Journals (Sweden)
Yana Valeryevna Dyomina
2015-09-01
Full Text Available The paper examines evolution of trade integration process in ASEAN. The author employs three methods in order to evaluate the degree of ASEAN‘s trade integration that has been achieved over two decades since the signing of the Association of South-East Asian Nations Free Trade Area Agreement (AFTA in 1992. The high degree of trade integration among member states allows moving to the next stage of international economic integration (ASEAN countries are going to form ASEAN Community (the Common Market by the 1st of January 2016. So the study assesses the ASEAN’s preparedness to the Common Market by determining the share of mutual (intraregional trade, regional trade intensity index (RTII and trade integration effects (trade creation and trade diversion effects for each member state, 2 groups of ASEAN countries (ASEAN-6 and ASEAN-4 and the Association as a whole. The paper shows that despite the increase in the share of intraregional trade during the years of the AFTA functioning, the member states of ASEAN still demonstrate low levels of trade integration: a 75% of the Association’s external trade focuses on extra regional partners; b ASEAN as a whole has the low volume of RTII and among its member states only Singapore has the high one; c trade diversion effect prevails over trade creation one
International Nuclear Information System (INIS)
Sun, J. D.; Qin, H.; Yang, X. X.; Zhang, Z. P.; Li, X. X.; Zhang, X. Y.; Cai, Y.; Wu, D. M.; Zhang, B. S.; Lewis, R. A.; Sun, Y. F.
2015-01-01
The effect of the symmetries in the terahertz (THz) field distribution and the field-effect channel on THz photoresponse is examined. Resonant excitation of cavity plasmon modes and nonresonant self-mixing of THz waves are demonstrated in a GaN/AlGaN two-dimensional electron gas with symmetrically designed nanogates, antennas, and filters. We found that the self-mixing signal can be effectively suppressed by the symmetric design and the resonant response benefits from the residual asymmetry. The findings suggest that a single detector may provide both high sensitivity from the self-mixing mechanism and spectral resolution from the resonant response by optimizing the degree of geometrical and/or electronic symmetries
Parallel gradient effects on ICRH (Ion Cyclotron Resonance Heating) in Tokamaks
International Nuclear Information System (INIS)
Smithe, D.N.
1987-01-01
This dissertation examines the effects on Ion Cyclotron Resonance Heating of parallel nonuniformity in the magnetic field which arises from the poloidal field in a tokamak and the universal (major radius)/sup /minus/1/ scaling of the cyclotron frequency. The goal of the analysis is the macroscopic warm plasma current including temperature in the sense of the finite Larmor radius expansion and the quasilocal approximation of the parallel guiding center motion. A 1-D numerical application of the fully nonlocal integral dielectric is performed. Parallel gradient effects are studied for He-3 minority, 2nd harmonic deuterium, and hydrogen minority heating in tokamaks. The results show quite significant alteration of the toroidal wavenumber absorption spectrum, and a wealth of new behavior on the local propagation scale. 95 refs., 37 figs
Resonant magnetic perturbation effect on tearing mode dynamics
International Nuclear Information System (INIS)
Frassinetti, L.; Olofsson, K.E.J.; Brunsell, P.R.; Drake, J.R.
2010-01-01
The effect of a resonant magnetic perturbation (RMP) on the tearing mode (TM) dynamics is experimentally studied in the EXTRAP T2R device. EXTRAP T2R is equipped with a set of sensor coils and active coils connected by a digital controller allowing a feedback control of the magnetic instabilities. The recently upgraded feedback algorithm allows the suppression of all the error field harmonics but keeping a selected harmonic to the desired amplitude, therefore opening the possibility of a clear study of the RMP effect on the corresponding TM. The paper shows that the RMP produces two typical effects: (1) a weak oscillation in the TM amplitude and a modulation in the TM velocity or (2) a strong modulation in the TM amplitude and phase jumps. Moreover, the locking mechanism of a TM to a RMP is studied in detail. It is shown that before the locking, the TM dynamics is characterized by velocity modulation followed by phase jumps. Experimental results are reasonably explained by simulations obtained with a model.
Integrated optics ring-resonator chemical sensor for detection of air contamination
Manfreda, A. M.; Homer, M. L.; Ksendzov, A.
2004-01-01
We report a silicon nitride-based ring resonator chemical sensor with sensing polymer coating. Its sensitivity to isopropanol in air is at least 50 ppm - well under the permissible exposure level of 400 ppm.
International Nuclear Information System (INIS)
Zhang, Mengying; Zhao, Zhan; Du, Lidong; Fang, Zhen
2017-01-01
This paper presented a high-performance pressure sensor based on a film bulk acoustic resonator (FBAR). The support film of the FBAR chip was made of silicon nitride and the part under the resonator area was etched to enhance the sensitivity and improve the linearity of the pressure sensor. A micro resistor temperature sensor and a micro resistor heater were integrated in the chip to monitor and control the operating temperature. The sensor chip was fabricated, and packaged in an oscillator circuit for differential pressure detection. When the detected pressure ranged from −100 hPa to 600 hPa, the sensitivity of the improved FBAR pressure sensor was −0.967 kHz hPa −1 , namely −0.69 ppm hPa −1 , which was 19% higher than that of existing sensors with a complete support film. The nonlinearity of the improved sensor was less than ±0.35%, while that of the existing sensor was ±5%. To eliminate measurement errors from humidity, the temperature control system integrated in the sensor chip controlled the temperature of the resonator up to 75 °C, with accuracy of ±0.015 °C and power of 20 mW. (paper)
Simeonov, Plamen L; Ehresmann, Andrée C
2017-12-01
Forty-two years ago, Capra published "The Tao of Physics" (Capra, 1975). In this book (page 17) he writes: "The exploration of the atomic and subatomic world in the twentieth century has …. necessitated a radical revision of many of our basic concepts" and that, unlike 'classical' physics, the sub-atomic and quantum "modern physics" shows resonances with Eastern thoughts and "leads us to a view of the world which is very similar to the views held by mystics of all ages and traditions." This article stresses an analogous situation in biology with respect to a new theoretical approach for studying living systems, Integral Biomathics (IB), which also exhibits some resonances with Eastern thought. Stepping on earlier research in cybernetics 1 and theoretical biology, 2 IB has been developed since 2011 by over 100 scientists from a number of disciplines who have been exploring a substantial set of theoretical frameworks. From that effort, the need for a robust core model utilizing advanced mathematics and computation adequate for understanding the behavior of organisms as dynamic wholes was identified. At this end, the authors of this article have proposed WLIMES (Ehresmann and Simeonov, 2012), a formal theory for modeling living systems integrating both the Memory Evolutive Systems (Ehresmann and Vanbremeersch, 2007) and the Wandering Logic Intelligence (Simeonov, 2002b). Its principles will be recalled here with respect to their resonances to Eastern thought. Copyright © 2017 Elsevier Ltd. All rights reserved.
[Effectiveness of integrative psychotherapeutic counseling for students].
Sperth, Michael; Hofmann, Frank-Hagen; Holm-Hadulla, Rainer Mathias
2014-06-01
In this first effectiveness study of psychotherapeutic counseling for students in German-speaking countries, the effectiveness of an integrative model of counseling was evaluated based on a sample of 151 clients. Effectiveness of integrative counseling according to the ABCDE-model was found to be high in comparison to other international studies in this area. Pre-post differences on measures of mental distress and satisfaction were significant and effect sizes were mostly moderate to high. A high percentage of clients improved statistically and clinically significant. Counselors' expert rating and diagnostics according to ICD-10 that have been included in contrast to previous effectiveness studies showed that clients suitable for the counseling setting get treated in the counseling center while more severely disturbed clients in terms of psychopathology or diagnosis get referred to outpatient treatment, drop out or object to provide post-data. © Georg Thieme Verlag KG Stuttgart · New York.
New WIMS library generation from ENDF/B6 and effect of resonance group structure on cell parameters
International Nuclear Information System (INIS)
Pazirandeh, Ali; Tabesh, Alireza
2002-01-01
Due to inaccessibility to NJOY, steps were taken to create WIMS library, which can be extracted from ENDF/B6 without using NJOY. In addition to using preprocessing codes few programs were written to calculate integral resonance, slowing down power per unit lethargy, potential scattering, and differential scattering cross section, scattering matrices. For neutrons with energy above 4 eV, isotropic elastic scattering was assumed. For neutrons below 4 eV the free gas model was used, except for light elements, which tabulated values of S(α,β) in ENDF/B6 used. The Goldstein-Cohen factors are taken from WIMKAL88.Lib. The integral resonance with self absorption per unit lethargy was obtained from GROUPIE output. The P 1 scattering matrices are calculated only for four elements, namely H, D, C and O at 300 K. In order to examine the created libraries, k eff , δ 28 , ρ 28 , ρ 25 and CR are calculated using new WIMS library, WIMKAL88.Lib and NEA329.Lib. The results showed general agreement. The controversial issue of WIMS library group structure, particularly in resonance region has raised the question of whether the number of resonance group i.e., 13 is optimized. We generated different WIMS libraries consisting of 5, 8, 13, 18 and 23 resonance groups. The main aim was to examine the effect to resonance group structure on calculated core parameters, mainly, k eff , δ 28 , ρ 28 , ρ 25 and CR. These parameters are also calculated and compared with those obtained using WIMKAL88, and NEA329 libraries. (author)
Integrability in heavy quark effective theory
Braun, Vladimir M.; Ji, Yao; Manashov, Alexander N.
2018-06-01
It was found that renormalization group equations in the heavy-quark effective theory (HQET) for the operators involving one effective heavy quark and light degrees of freedom are completely integrable in some cases and are related to spin chain models with the Hamiltonian commuting with the nondiagonal entry C( u) of the monodromy matrix. In this work we provide a more complete mathematical treatment of such spin chains in the QISM framework. We also discuss the relation of integrable models that appear in the HQET context with the large-spin limit of integrable models in QCD with light quarks. We find that the conserved charges and the "ground state" wave functions in HQET models can be obtained from the light-quark counterparts in a certain scaling limit.
'Blocking' effects in magnetic resonance? The ferromagnetic nanowires case
International Nuclear Information System (INIS)
Ramos, C.A.; De Biasi, E.; Zysler, R.D.; Vassallo Brigneti, E.; Vazquez, M.
2007-01-01
We present magnetic resonance results obtained at L, X, and Q bands (1.2, 9.4 and 34GHz, respectively) on ferromagnetic nanowires with a hysteresis cycle characterized by a remanent magnetization M r /M s ∼0.92 and a coercive field H c =1.0kOe. The hysteretic response of the ferromagnetic resonance spectra is discussed in terms of independent contributions of the nanowires aligned along and opposite to the applied field. We will discuss the implications of this study on the magnetic resonance in nanoparticles and other systems with large anisotropy
Resonant effects on the low frequency vlasov stability of axisymmetric field reversed configurations
International Nuclear Information System (INIS)
Finn, J.M.; Sudan, R.N.
We investigate the effect of particle resonances on low frequency MHD modes in field-reversed geometries, e.g., an ion ring. It is shown that, for sufficiently high field reversal, modes which are hydromagnetically stable can be driven unstable by ion resonances. The stabilizing effect of a toroidal magnetic field is discussed
The problem of resonance self-shielding effect in neutron multigroup calculations
International Nuclear Information System (INIS)
Wang Qingming; Huang Jinghua
1991-01-01
It is not allowed to neglect the resonance self-shielding effect in hybrid blanket and fast reactor neutron designs. The authors discussed the importance as well as the method of considering the resonance self-shielding effect in hybrid blanket and fast reactor neutron multigroup calculations
Thermal and particle size distribution effects on the ferromagnetic resonance in magnetic fluids
International Nuclear Information System (INIS)
Marin, C.N.
2006-01-01
Thermal and particle size distribution effects on the ferromagnetic resonance of magnetic fluids were theoretically investigated, assuming negligible interparticle interactions and neglecting the viscosity of the carrier liquid. The model is based on the usual approach for the ferromagnetic resonance description of single-domain magnetic particle systems, which was amended in order to take into account the finite particle size effect, the particle size distribution and the orientation mobility of the particles within the magnetic fluid. Under these circumstances the shape of the resonance line, the resonance field and the line width are found to be strongly affected by the temperature and by the particle size distribution of magnetic fluids
Optical pulling force and conveyor belt effect in resonator-waveguide system.
Intaraprasonk, Varat; Fan, Shanhui
2013-09-01
We present the theoretical condition and actual numerical design that achieves an optical pulling force in resonator-waveguide systems, where the direction of the force on the resonator is in the opposite direction to the input light in the waveguide. We also show that this pulling force can occur in conjunction with the lateral optical equilibrium effect, such that the resonator is maintained at the fixed distance from the waveguide while experiencing the pulling force.
International Nuclear Information System (INIS)
Marin, C.N.
2002-01-01
Based on the assumption of particle chains formation within a magnetic liquid, computer simulation of the magnetic resonance line is presented. The dependence on particle concentration within a magnetic liquid of magnetic resonance linewidth is analyzed. The computer simulation demonstrates that the particles chaining has an important effect on the enlargement of the magnetic resonance line. Increasing the particle concentration within magnetic liquid leads to an increase in the linewidth. The agreement with some experimental findings is discussed
Directory of Open Access Journals (Sweden)
Ke Gong
2018-01-01
Full Text Available A series-fed linear substrate-integrated dielectric resonator antenna array (SIDRAA is presented for millimeter-wave applications, in which the substrate-integrated dielectric resonator antenna (SIDRA elements and the feeding structure can be codesigned and fabricated using the same planar process. A prototype 4 × 1 SIDRAA is designed at Ka-band and fabricated with a two-layer printed circuit board (PCB technology. Four SIDRAs are implemented in the Rogers RT6010 substrate using the perforation technique and fed by a compact substrate-integrated waveguide (SIW through four longitudinal coupling slots within the Rogers RT5880 substrate. The return loss, radiation patterns, and antenna gain were experimentally studied, and good agreement between the measured and simulated results is observed. The SIDRAA example provides a bandwidth of about 10% around 34.5 GHz for 10 dB return loss and stable broadside radiation patterns with the peak gain of 10.5–11.5 dBi across the band.
Directory of Open Access Journals (Sweden)
Sascha Geidel
2016-09-01
Full Text Available While there have been huge advances in the field of biosensors during the last decade, their integration into a microfluidic environment avoiding external tubing and pumping is still neglected. Herein, we show a new microfluidic design that integrates multiple reservoirs for reagent storage and single-use electrochemical pumps for time-controlled delivery of the liquids. The cartridge has been tested and validated with a silicon nitride-based photonic biosensor incorporating multiple optical ring resonators as sensing elements and an immunoassay as a potential target application. Based on experimental results obtained with a demonstration model, subcomponents were designed and existing protocols were adapted. The newly-designed microfluidic cartridges and photonic sensors were separately characterized on a technical basis and performed well. Afterwards, the sensor was functionalized for a protein detection. The microfluidic cartridge was loaded with the necessary assay reagents. The integrated pumps were programmed to drive the single process steps of an immunoassay. The prototype worked selectively, but only with a low sensitivity. Further work must be carried out to optimize biofunctionalization of the optical ring resonators and to have a more suitable flow velocity progression to enhance the system’s reproducibility.
Arvanitis, Costas D; McDannold, Nathan
2013-11-01
Ultrasound can be used to noninvasively produce different bioeffects via viscous heating, acoustic cavitation, or their combination, and these effects can be exploited to develop a wide range of therapies for cancer and other disorders. In order to accurately localize and control these different effects, imaging methods are desired that can map both temperature changes and cavitation activity. To address these needs, the authors integrated an ultrasound imaging array into an MRI-guided focused ultrasound (MRgFUS) system to simultaneously visualize thermal and mechanical effects via passive acoustic mapping (PAM) and MR temperature imaging (MRTI), respectively. The system was tested with an MRgFUS system developed for transcranial sonication for brain tumor ablation in experiments with a tissue mimicking phantom and a phantom-filled ex vivo macaque skull. In experiments on cavitation-enhanced heating, 10 s continuous wave sonications were applied at increasing power levels (30-110 W) until broadband acoustic emissions (a signature for inertial cavitation) were evident. The presence or lack of signal in the PAM, as well as its magnitude and location, were compared to the focal heating in the MRTI. Additional experiments compared PAM with standard B-mode ultrasound imaging and tested the feasibility of the system to map cavitation activity produced during low-power (5 W) burst sonications in a channel filled with a microbubble ultrasound contrast agent. When inertial cavitation was evident, localized activity was present in PAM and a marked increase in heating was observed in MRTI. The location of the cavitation activity and heating agreed on average after registration of the two imaging modalities; the distance between the maximum cavitation activity and focal heating was -3.4 ± 2.1 mm and -0.1 ± 3.3 mm in the axial and transverse ultrasound array directions, respectively. Distortions and other MRI issues introduced small uncertainties in the PAM
Bloemen, Oswald J. N.; Deeley, Quinton; Sundram, Fred; Daly, Eileen M.; Barker, Gareth J.; Jones, Derek K.; van Amelsvoort, Therese A. M. J.; Schmitz, Nicole; Robertson, Dene; Murphy, Kieran C.; Murphy, Declan G. M.
2010-01-01
Background: Autistic Spectrum Disorder (ASD), including Asperger syndrome and autism, is a highly genetic neurodevelopmental disorder. There is a consensus that ASD has a biological basis, and it has been proposed that it is a "connectivity" disorder. Diffusion Tensor Magnetic Resonance Imaging
All-optical control of microfiber resonator by graphene's photothermal effect
International Nuclear Information System (INIS)
Wang, Yadong; Gan, Xuetao; Zhao, Chenyang; Fang, Liang; Mao, Dong; Zhang, Fanlu; Xi, Teli; Zhao, Jianlin; Xu, Yiping; Ren, Liyong
2016-01-01
We demonstrate an efficient all-optical control of microfiber resonator assisted by graphene's photothermal effect. Wrapping graphene onto a microfiber resonator, the light-graphene interaction can be strongly enhanced via the resonantly circulating light, which enables a significant modulation of the resonance with a resonant wavelength shift rate of 71 pm/mW when pumped by a 1540 nm laser. The optically controlled resonator enables the implementation of low threshold optical bistability and switching with an extinction ratio exceeding 13 dB. The thin and compact structure promises a fast response speed of the control, with a rise (fall) time of 294.7 μs (212.2 μs) following the 10%–90% rule. The proposed device, with the advantages of compact structure, all-optical control, and low power acquirement, offers great potential in the miniaturization of active in-fiber photonic devices.
All-optical control of microfiber resonator by graphene's photothermal effect
Energy Technology Data Exchange (ETDEWEB)
Wang, Yadong; Gan, Xuetao; Zhao, Chenyang; Fang, Liang; Mao, Dong; Zhang, Fanlu; Xi, Teli; Zhao, Jianlin, E-mail: jlzhao@nwpu.edu.cn [Key Laboratory of Space Applied Physics and Chemistry, Ministry of Education, and Shaanxi Key Laboratory of Optical Information Technology, School of Science, Northwestern Polytechnical University, Xi' an 710072 (China); Xu, Yiping; Ren, Liyong [State Key Laboratory of Transient Optics and Photonics, Xi' an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi' an 710119 (China)
2016-04-25
We demonstrate an efficient all-optical control of microfiber resonator assisted by graphene's photothermal effect. Wrapping graphene onto a microfiber resonator, the light-graphene interaction can be strongly enhanced via the resonantly circulating light, which enables a significant modulation of the resonance with a resonant wavelength shift rate of 71 pm/mW when pumped by a 1540 nm laser. The optically controlled resonator enables the implementation of low threshold optical bistability and switching with an extinction ratio exceeding 13 dB. The thin and compact structure promises a fast response speed of the control, with a rise (fall) time of 294.7 μs (212.2 μs) following the 10%–90% rule. The proposed device, with the advantages of compact structure, all-optical control, and low power acquirement, offers great potential in the miniaturization of active in-fiber photonic devices.
The effect of integrated reporting on integrated thinking between risk ...
African Journals Online (AJOL)
... between strategy and the risks and opportunities faced by the organisation. For this purpose, a web-based research questionnaire was sent to high-level implementers of integrated reporting at companies listed on the Johannesburg Stock Exchange (JSE) in South Africa, where integrated reporting is a listing requirement.
Resonant circular photogalvanic effect in GaN/AlGaN heterojunctions
Wittmann, B.; Golub, L. E.; Danilov, S. N.; Karch, J.; Reitmaier, C.; Kvon, Z. D.; Vinh, N. Q.; van der Meer, A. F. G.; Murdin, B.; Ganichev, S. D.
2008-01-01
The resonant circular photogalvanic effect is observed in wurtzite (0001)-oriented GaN low-dimensional structures excited by infrared radiation. The current is induced by angular-momentum transfer of photons to the photoexcited electrons at resonant intersubband optical transitions in a GaN/AlGaN
A Study of the Resonance Interaction Effect between 238U and 239Pu in Lower Energy Region
International Nuclear Information System (INIS)
Haeggblom, H.
1968-12-01
An investigation has been made of the statistical frequency function for the distances between the 238 U and the 239 Pu resonances in the region 4-244 eV. It is concluded that the frequency function is probably constant but that the distances diverge appreciably from a constant function in the actual case, and that the divergence is such that the interaction effect on the resonance integral is smaller than would be expected from statistical considerations. This is also confirmed by calculations on the interaction effect. These have been performed using three different methods, namely: a) considering the actual positions and widths of the resonances, b) assuming a constant frequency function for the resonance. spacing and applying a theory developed by Rowlands and E A Fischer. c) applying a simplified, approximate method for calculations based on the statistical theory. The calculations are made for two temperatures and two values of the plutonium enrichment. It is shown that the average cross sections are considerably larger than the statistical calculations indicate
Energy Technology Data Exchange (ETDEWEB)
Haeggblom, H
1968-12-15
An investigation has been made of the statistical frequency function for the distances between the {sup 238}U and the {sup 239}Pu resonances in the region 4-244 eV. It is concluded that the frequency function is probably constant but that the distances diverge appreciably from a constant function in the actual case, and that the divergence is such that the interaction effect on the resonance integral is smaller than would be expected from statistical considerations. This is also confirmed by calculations on the interaction effect. These have been performed using three different methods, namely: a) considering the actual positions and widths of the resonances, b) assuming a constant frequency function for the resonance. spacing and applying a theory developed by Rowlands and E A Fischer. c) applying a simplified, approximate method for calculations based on the statistical theory. The calculations are made for two temperatures and two values of the plutonium enrichment. It is shown that the average cross sections are considerably larger than the statistical calculations indicate.
Possible resonance effect of axionic dark matter in Josephson junctions.
Beck, Christian
2013-12-06
We provide theoretical arguments that dark-matter axions from the galactic halo that pass through Earth may generate a small observable signal in resonant S/N/S Josephson junctions. The corresponding interaction process is based on the uniqueness of the gauge-invariant axion Josephson phase angle modulo 2π and is predicted to produce a small Shapiro steplike feature without externally applied microwave radiation when the Josephson frequency resonates with the axion mass. A resonance signal of so far unknown origin observed by C. Hoffmann et al. [Phys. Rev. B 70, 180503(R) (2004)] is consistent with our theory and can be interpreted in terms of an axion mass m(a)c2=0.11 meV and a local galactic axionic dark-matter density of 0.05 GeV/cm3. We discuss future experimental checks to confirm the dark-matter nature of the observed signal.
Magnetic hysteresis effects in superconducting coplanar microwave resonators
Energy Technology Data Exchange (ETDEWEB)
Bothner, D.; Gaber, T.; Kemmler, M.; Gruenzweig, M.; Ferdinand, B.; Koelle, D.; Kleiner, R. [Universitaet Tuebingen (Germany); Wuensch, S.; Siegel, M. [Karlsruher Institut fuer Technologie (Germany); Mikheenko, P.; Johansen, T.H. [University of Oslo (Norway)
2013-07-01
We present experimental data regarding the impact of external magnetic fields on quality factor and resonance frequency of superconducting microwave resonators in a coplanar waveguide geometry. In particular we focus on the influence of magnetic history and show with the assistance of numerical calculations that the found hysteretic behaviour can be well understood with a highly inhomogeneous microwave current density in combination with established field penetration models for type-II superconducting thin films. Furthermore we have used magneto-optical imaging techniques to check the field distribution which we have assumed in our calculations. Finally, we demonstrate that and how the observed hysteretic behaviour can be used to optimize and tune the resonator performance for possible hybrid quantum sytems in magnetic fields.
Magnetic resonance imaging: effects of magnetic field strength
International Nuclear Information System (INIS)
Crooks, L.E.; Arakawa, M.; Hoenninger, J.; McCarten, B.; Watts, J.; Kaufman, L.
1984-01-01
Magnetic resonance images of the head, abdomen, and pelvis of normal adult men were obtained using varying magnetic field strength, and measurements of T1 and T2 relaxations and of signal-to-noise (SN) ratios were determined. For any one spin echo sequence, gray/white matter contrast decreases and muscle/fat contrast increases with field. SN levels rise rapidly up to 3.0 kgauss and then change more slowly, actually dropping for muscle. The optimum field for magnetic resonance imaging depends on tissue type, body part, and imaging sequence, so that it does not have a unique value. Magnetic resonance systems that operate in the 3.0-5.0 kgauss range achieve most or all of the gains that can be achieved by higher magnetic fields
Batra, Prag; Bandt, S. Kathleen; Leuthardt, Eric C.
2016-01-01
Background: Awake craniotomy is currently the gold standard for aggressive tumor resections in eloquent cortex. However, a significant subset of patients is unable to tolerate this procedure, particularly the very young or old or those with psychiatric comorbidities, cardiopulmonary comorbidities, or obesity, among other conditions. In these cases, typical alternative procedures include biopsy alone or subtotal resection, both of which are associated with diminished surgical outcomes. Case Description: Here, we report the successful use of a preoperatively obtained resting state functional connectivity magnetic resonance imaging (MRI) integrated with intraoperative neuronavigation software in order to perform functional cortical mapping in the setting of an aborted awake craniotomy due to loss of airway. Conclusion: Resting state functional connectivity MRI integrated with intraoperative neuronavigation software can provide an alternative option for functional cortical mapping in the setting of an aborted awake craniotomy. PMID:26958419
Directory of Open Access Journals (Sweden)
Weifeng Zhang
2016-11-01
Full Text Available Silicon photonics with advantages of small footprint, compatibility with the mature CMOS fabrication technology, and its potential for seamless integration with electronics is making a significant difference in realizing on-chip integration of photonic systems. A microdisk resonator (MDR with a strong capacity in trapping and storing photons is a versatile element in photonic integrated circuits. Thanks to the large index contrast, a silicon-based MDR with an ultra-compact footprint has a great potential for large-scale and high-density integrations. However, the existence of multiple whispering gallery modes (WGMs and resonance splitting in an MDR imposes inherent limitations on its widespread applications. In addition, the waveguide structure of an MDR is incompatible with that of a lateral PN junction, which leads to the deprivation of its electrical tunability. To circumvent these limitations, in this paper we propose a novel design of a silicon-based MDR by introducing a specifically designed slab waveguide to surround the disk and the lateral sides of the bus waveguide to suppress higher-order WGMs and to support the incorporation of a lateral PN junction for electrical tunability. An MDR based on the proposed design is fabricated and its optical performance is evaluated. The fabricated MDR exhibits single-mode operation with a free spectral range of 28.85 nm. Its electrical tunability is also demonstrated and an electro-optic frequency response with a 3-dB modulation bandwidth of ∼30.5 GHz is measured. The use of the fabricated MDR for the implementation of an electrically tunable optical delay-line and a tunable fractional-order temporal photonic differentiator is demonstrated.
Calculation of the fine spectrum and integration of the resonance cross sections in the cells
International Nuclear Information System (INIS)
Paratte, J.M.
1986-10-01
The code BOXER is used for the neutronics calculations of two-dimensional LWR arrays. During the calculation of the group constants of the cells (pin, clad and moderator), the program SLOFIN, a BOXER module, allows taking into account the self-shielding of the resonances. The resonance range is devided into two parts: - above 907 eV the cross sections are condensed into groups by the library code ETOBOX. In SLOFIN, these values are interpolated over the equivalent cross section and the temperature. The interpolation formula chosen gives an accuracy better than 1% for values of the equivalent cross section larger than 5 barns. - between 4 and 907 eV, the cross sections are given in pointwise form as a function of the lethargy. At first a list of pointwise macroscopic cross section is established. Then the fine spectrum in the cell is calculated in 2 or 3 zones by means of the collision probability theory. In the central zone one resonant pseudo-nuclide is considered for the calculation of the scattering source, while the light nuclides are explicitly treated but under the assumption of energy independent cross sections. The fine spectrum is then used as a weihting function for the condensation of the pointwise cross sections of the resonant nuclides into energy groups. The procedure was checked on the basis of the TRX-1 to -4 and BAPL-UO 2 -1 to -3 experiments which are used as benchmarks for the tests of the ENDF/B libraries. The comparisons with other calculation results show that the deviations observed are typical for the basic cross sections. The method proposed shows a good accuracy in the application range foreseen for BOXER. It is also fast enough to be used as a standard method in a cell code. (author)
High-Q Superconducting Coplanar Waveguide Resonators for Integration into Molecule Ion Traps
2010-05-01
V12C (3.13) 4 and We = V12 (3.14) 4 w 2 L’ finally yielding 2Wm R Q = wo m - w0L= woRC, (3.15) where wo = 1/ vLC is the resonant frequency of the...small. The primary challenge with simulating the microresonators was refining the mesh while remaining under memory limits of the modeling computer. It
Effect of Initial Curvature on the Static and Dynamic Behavior of MEMS Resonators
Hajjaj, Amal Z.
2017-11-03
In this paper, we investigate experimentally and analytically the effect of the initial shape, arc and cosine wave, on the static and dynamic behavior of microelectromechanical (MEMS) resonators. We show that by carefully choosing the geometrical parameters and the shape of curvature, the veering phenomenon (avoided-crossing) between the first two symmetric modes can be activated. To demonstrate this concept, we study electrothermally tuned and electrostatically driven MEMS initially curved resonators. Applying electrothermal voltage heats up the beams and then increases their curvature (stiffness) and controls their resonance frequencies. While changing the electrothermal voltage, we demonstrate high frequency tunability of arc resonators compared to the cosine-configuration resonators for the first and third resonance frequencies. For arc beams, we show that the first resonance frequency increases up to twice its fundamental value and the third resonance frequency decreases until getting very close to the first resonance frequency triggering the veering phenomenon. Around the veering regime, we study experimentally and analytically, using a reduced order model based on a nonlinear Euler-Bernoulli shallow arch beam model, the dynamic behavior of the arc beam for different electrostatic forcing.
The effect of integrated reporting on integrated thinking between risk ...
African Journals Online (AJOL)
IIRC (2013b: 3), integrated thinking takes into account the connectivity and ... historical information and provides investors and other stakeholders with .... in the disclosure of risks and opportunities by using a sample of the top 100 JSE-.
Zhang, Hao; Li, Wenxiu; Han, Peng; Chang, Xiaoyang; Liu, Jiaming; Lin, Jian; Xue, Xia; Zhu, Fang; Yang, Yang; Liu, Xiaojing; Zhang, Xiaofu; Huang, Anping; Xiao, Zhisong; Fang, Jiancheng
2018-01-01
Anomalous dispersion enhancement physical mechanism for Sagnac effect is described by special relativity derivation, and three kinds of definitions of minimum detectable angular rate of resonance optical gyroscope (ROG) are compared and the relations among them are investigated. The effect of linewidth broadening induced by anomalous dispersion on the sensitivity of ROG is discussed in this paper. Material dispersion-broadened resonance linewidth deteriorates the performance of a passive ROG and dispersion enhancement effect, while the sensitivity of a structural dispersion ROG is enhanced by two orders of magnitude even considering the dispersion-broadened resonance linewidth.
Evidence for deformation effect on the giant monopole resonance
International Nuclear Information System (INIS)
Buenerd, M.; Lebrun, D.; Martin, P.; de Saintignon, P.; Perrin, C.
1980-01-01
The giant monopole resonance in the region of deformed nuclei has been investigated by inelastic scattering of 108.5 MeV 3 He at very small scattering angles. Evidence is reported for coupling between the giant monopole and giant quadrupole vibrations, based both on energy shift and transition strength
Internal additive noise effects in stochastic resonance using organic field effect transistor
Energy Technology Data Exchange (ETDEWEB)
Suzuki, Yoshiharu; Asakawa, Naoki [Division of Molecular Science, Graduate School of Science and Technology, Gunma University, 1-5-1 Tenjin-cho, Kiryu, Gunma 376-8515 (Japan); Matsubara, Kiyohiko [KOOROGI LLC, 6-1585-1-B Sakaino-cho, Kiryu, Gunma 376-0002 (Japan)
2016-08-29
Stochastic resonance phenomenon was observed in organic field effect transistor using poly(3-hexylthiophene), which enhances performance of signal transmission with application of noise. The enhancement of correlation coefficient between the input and output signals was low, and the variation of correlation coefficient was not remarkable with respect to the intensity of external noise, which was due to the existence of internal additive noise following the nonlinear threshold response. In other words, internal additive noise plays a positive role on the capability of approximately constant signal transmission regardless of noise intensity, which can be said “homeostatic” behavior or “noise robustness” against external noise. Furthermore, internal additive noise causes emergence of the stochastic resonance effect even on the threshold unit without internal additive noise on which the correlation coefficient usually decreases monotonically.
Effects of time delay on stochastic resonance of the stock prices in financial system
International Nuclear Information System (INIS)
Li, Jiang-Cheng; Li, Chun; Mei, Dong-Cheng
2014-01-01
The effect of time delay on stochastic resonance of the stock prices in finance system was investigated. The time delay is introduced into the Heston model driven by the extrinsic and intrinsic periodic information for stock price. The signal power amplification (SPA) was calculated by numerical simulation. The results indicate that an optimal critical value of delay time maximally enhances the reverse-resonance in the behaviors of SPA as a function of long-run variance of volatility or cross correlation coefficient between noises for both cases of intrinsic and extrinsic periodic information. Moreover, in both cases, being a critical value in the delay time, when the delay time takes value below the critical value, reverse-resonance increases with the delay time increasing, however, when the delay time takes value above the critical value, the reverse-resonance decrease with the delay time increasing. - Highlights: • The effects of delay time on stochastic resonance of the stock prices was investigated. • There is an optimal critical value of delay time maximally enhances the reverse-resonance • The reverse-resonance increases with the delay time increasing as the delay time takes value below the critical value • The reverse-resonance decrease with the delay time increasing as the delay time takes value above the critical value
Effects of time delay on stochastic resonance of the stock prices in financial system
Energy Technology Data Exchange (ETDEWEB)
Li, Jiang-Cheng [Department of Physics, Yunnan University, Kunming, 650091 (China); Li, Chun [Department of Computer Science, Puer Teachers' College, Puer 665000 (China); Mei, Dong-Cheng, E-mail: meidch@ynu.edu.cn [Department of Physics, Yunnan University, Kunming, 650091 (China)
2014-06-13
The effect of time delay on stochastic resonance of the stock prices in finance system was investigated. The time delay is introduced into the Heston model driven by the extrinsic and intrinsic periodic information for stock price. The signal power amplification (SPA) was calculated by numerical simulation. The results indicate that an optimal critical value of delay time maximally enhances the reverse-resonance in the behaviors of SPA as a function of long-run variance of volatility or cross correlation coefficient between noises for both cases of intrinsic and extrinsic periodic information. Moreover, in both cases, being a critical value in the delay time, when the delay time takes value below the critical value, reverse-resonance increases with the delay time increasing, however, when the delay time takes value above the critical value, the reverse-resonance decrease with the delay time increasing. - Highlights: • The effects of delay time on stochastic resonance of the stock prices was investigated. • There is an optimal critical value of delay time maximally enhances the reverse-resonance • The reverse-resonance increases with the delay time increasing as the delay time takes value below the critical value • The reverse-resonance decrease with the delay time increasing as the delay time takes value above the critical value.
Blueshift of the surface plasmon resonance in silver nanoparticles: substrate effects
DEFF Research Database (Denmark)
Raza, Søren; Yan, Wei; Stenger, Nicolas
2013-01-01
We study the blueshift of the surface plasmon (SP) resonance energy of isolated Ag nanoparticles with decreasing particle diameter, which we recently measured using electron energy loss spectroscopy (EELS) [1]. As the particle diameter decreases from 26 down to 3.5 nm, a large blueshift of 0.5 e......V of the SP resonance energy is observed. In this paper, we base our theoretical interpretation of our experimental findings on the nonlocal hydrodynamic model, and compare the effect of the substrate on the SP resonance energy to the approach of an effective homogeneous background permittivity. We derive...
Liu, Guoxi; Zhang, Chunli; Chen, Weiqiu; Dong, Shuxiang
2013-07-01
An analytical model of resonant magnetoelectric (ME) coupling in magnetostrictive (MS)-piezoelectric (PE) laminated composites in consideration of eddy-current effect in MS layer using equivalent circuit method is presented. Numerical calculations show that: (1) the eddy-current has a strong effect on ME coupling in MS-PE laminated composites at resonant frequency; and (2) the resonant ME coupling is then significantly dependent on the sizes of ME laminated composites, which were neglected in most previous theoretical analyses. The achieved results provide a theoretical guidance for the practice engineering design, manufacture, and application of ME laminated composites and devices.
Effect of Initial Curvature on the Static and Dynamic Behavior of MEMS Resonators
Hajjaj, Amal Z.; Alcheikh, Nouha; Younis, Mohammad I.
2017-01-01
In this paper, we investigate experimentally and analytically the effect of the initial shape, arc and cosine wave, on the static and dynamic behavior of microelectromechanical (MEMS) resonators. We show that by carefully choosing the geometrical
Su, Shujing; Lu, Fei; Wu, Guozhu; Wu, Dezhi; Tan, Qiulin; Dong, Helei; Xiong, Jijun
2017-08-25
The highly sensitive pressure sensor presented in this paper aims at wireless passive sensing in a high temperature environment by using microwave backscattering technology. The structure of the re-entrant resonator was analyzed and optimized using theoretical calculation, software simulation, and its equivalent lump circuit model was first modified by us. Micro-machining and high-temperature co-fired ceramic (HTCC) process technologies were applied to fabricate the sensor, solving the common problem of cavity sealing during the air pressure loading test. In addition, to prevent the response signal from being immersed in the strong background clutter of the hermetic metal chamber, which makes its detection difficult, we proposed two key techniques to improve the signal to noise ratio: the suppression of strong background clutter and the detection of the weak backscattered signal of the sensor. The pressure sensor demonstrated in this paper works well for gas pressure loading between 40 and 120 kPa in a temperature range of 24 °C to 800 °C. The experimental results show that the sensor resonant frequency lies at 2.1065 GHz, with a maximum pressure sensitivity of 73.125 kHz/kPa.
Increase in effectiveness of low frequency acoustic liners by use of coupled Helmholtz resonators
Dean, L. W.
1977-01-01
Coupling of Helmholtz resonators in a low-frequency absorber array was studied as a means for increasing the effectiveness for absorbing low-frequency core engine noise. The equations for the impedance of the coupled-resonator systems were developed in terms of uncoupled-resonator parameters, and the predicted impedance for a parallel-coupled scheme is shown to compare favorably with measurements from a test model. In addition, attenuation measurements made in a flow duct on test coupled-resonator panels are shown to compare favorably with predicted values. Finally, the parallel-coupled concept is shown to give significantly more attenuation than that of a typical uncoupled resonator array of the same total volume.
International Nuclear Information System (INIS)
Zaitsev, V.V.; Stepanov, A.V.
1982-01-01
It is shown that the existence of a minimum of the Alfven speed in the corona at a height of approx.1R/sub sun/ follows from the characteristics of type II radio bursts. The region of a reduced Alfven speed is a resonator for a fast magnetosonic (FMS) waves. The eigenmodes of the resonator are determined. The period of the fundamental mode has the order of several minutes. In the resonator FMS waves can be excited at the Cherenkov resonance by streams of energetic ions. Modulations of metal solar radio emission with a period of several minutes is explained by the effect of the propagation of radio waves through an oscillating magnetohydrodynamic (MHD) resonator
Single-top t-channel production with off-shell and non-resonant effects
International Nuclear Information System (INIS)
Papanastasiou, A.S.; Frederix, R.; Hirschi, V.; Maltoni, F.
2013-05-01
This letter details and discusses the next-to-leading order QCD corrections to t-channel electro-weak W + bj production, where finite top-width effects are consistently taken into account. The computation is done within the aMC rate at NLO framework and includes both resonant and non-resonant contributions as well as interferences between the two. Results are presented for the LHC and compared to those of the narrow-width approximation and effective theory approaches.
International Nuclear Information System (INIS)
Sinha, T.; Kanungo, R.; Samanta, C.; Ghosh, S.; Basu, P.; Rebel, H.
1996-01-01
Alpha- particle scattering from the resonant (3 + 1 ) and non-resonant continuum states of 6 Li is studied at incident energy 10 MeV/A. The α+d breakup continuum part within the excitation energy E ex = 1.475-2.475 MeV is discretized in two energy bins. Unlike the results at higher incident energies, here the coupled-channel calculations show significant breakup continuum coupling effects on the elastic and inelastic scattering. It is shown that even when the continuum-continuum coupling effects are strong, the experimental data of the ground state and the resonant as well as discretized non-resonant continuum states impose stringent constraint on the coupling strengths of the non-resonant continuum states. (orig.). With 2 figs., 1 tab
Chemical binding effects in resonance - potential interference scattering for harmonic crystals
International Nuclear Information System (INIS)
Kuwaifi, A.; Summerfield, G.C.
1991-01-01
The neutron scattering cross section which is the quantity directly measured in experiments is given by the absolute square of the scattering amplitude. For energies near a resonance, this yields three terms: potential, resonant and interference. In this paper we deal with the interference neutron scattering cross section which is written in terms of a three-point correlation function. This function is calculated for the ideal gas and harmonic crystal models. For short collision times, the interference result for harmonic crystals is the same as the ideal gas but it has an effective temperature. This is the same effective temperature as was previously found for absorption and pure resonant processes. Therefore, the interference scattering cross section can be treated in the same way as resonant scattering and absorption are treated using an ideal gas result with the usual effective temperature. (author)
Integrated microfluidic capillary in a waveguide resonator for chemical and biomedical sensing
International Nuclear Information System (INIS)
Pavuluri, S K; Lopez-Villarroya, R; McKeever, E; Goussetis, G; Desmulliez, M P Y; Kavanagh, D
2009-01-01
A novel microfluidic sensing device based on waveguide cavity filters is proposed for the characterisation, detection of cells in solution and chemical substances in micro-litre volumes. The sensor consists of a micromachined microfluidic channel within a waveguide-based resonator localised increased near-fields and could potentially be designed for different frequency regimes to improve the sensitivity. The present sensor has been proposed for fabrication in different manufacturing platforms and an initial prototype with a 100μm micromachined channel that is embedded within an X-band E-plane waveguide has been fabricated and tested. The design methodology for the microfluidic channel and the E-plane filter is also presented.
Development of Integrated Electronics for Readout of High Frequency Micro/Nano-mechanical Resonator
DEFF Research Database (Denmark)
Tang, Meng
Micro størrelse bulk type resonatorer er blevet udviklet gennern de sidste fem år til anvendelse inden for elektronikbranchen til lav strøm og billige alternativer til både passive og aktive komponenter. Dog kan denne type bulk resonator også bruges til bio/kemiske sensorer hvor, da på grund af den...... fri bevægelser omkring sin resonansfrekven. Metodens evne til at måle resonans frekvens, Q-faktor og den parallel kondensator på samme tid er verificeret både teoretisk og eksperimentelt i luft ved høj hastighed. Hertil kommer, at metoden ikke har brug for nogen kompliceret form for feedback som gøre...
Power Take-Off with Integrated Resonator for Energy Extraction from Linear Motions
DEFF Research Database (Denmark)
2014-01-01
The invention relates to a magnetic gear for converting linear motion into rotational motion and vice versa. The present invention converts slow linear irregular oscillating motion of wave energy devices into torque on a high speed shaft for powering a generator while making the wave energy device...... of sea or ocean waves into useful energy, such as electricity. The invention relates to the control and operation of a magnetic gear based motor/generator system. The invention provides a high force density electric powered linear actuator....... resonate with the waves. The invention relates to the field of energy-harvesting from energy sources, where the energy-harvesting requires the extraction of energy from slow and often irregular reciprocating motion of bodies. The present invention relates to a wave power apparatus for converting power...
Fully integrated Q-switch for commercial high-power resonator with solitary XLMA-fiber
Lange, R.; Bachert, C.; Rehmann, G.; Weber, H.; Luxen, R.; Enns, H.; Schenk, M.; Hosdorf, S.; Marfels, S.; Bay, M.; Kösters, A.; Krause, V.; Giesberts, M.; Fitzau, O.; Hoffmann, H.-D.
2018-02-01
In surface processing applications the correlation of laser power to processing speed demands a further enhancement of the performance of short-pulsed laser sources with respect to the investment costs. The frequently applied concept of master oscillator power amplifier relies on a complex structure, parts of which are highly sensitive to back reflected amplified radiation. Aiming for a simpler, robust source using only a single ytterbium doped XLMA fiber in a q-switched resonator appears as promising design approach eliminating the need for subsequent amplification. This concept requires a high power-tolerant resonator which is provided by the multikilowatt laser platform of Laserline including directly water-cooled active fiber thermal management. Laserline GmbH and Fraunhofer Institute for Laser Technology joined their forces1 to upgrade standard high power laser sources for short-pulsed operation exceeding 1 kW of average power. Therefor a compact, modular qswitch has been developed. In this paper the implementation of a polarization independent q-switch into an off-the-shelf multi-kilowatt diodepumped continuous wave fiber source is shown. In this early step of implementation we demonstrated more than 1000 W of average power at pulse lengths below 50 ns FWHM and 7.5 mJ pulse energy. The M2 corresponds to 9.5. Reliability of the system is demonstrated based on measurements including temperature and stability records. We investigated the variation possibilities concerning pulse parameters and shape as well as upcoming challenges in power up-scaling.
Energy Technology Data Exchange (ETDEWEB)
Sokolowski, E K; Bladh, R
1969-02-15
Pile oscillator measurements of heavy-water solutions of As, B, Mn and In have been carried out in two different neutron spectra in the R0 reactor. For B, Mn and In the 2200 m/s cross section values recommended in BNL-325 are given to within 1.5 % or less, while for As the stated uncertainty is 5 %. In the present work the BNL values for B, Mn and In were used to derive weighted mean calibration constants for the reactor, which were then in turn used for obtaining self-consistent cross section values for all four elements. The values thus obtained for B, Mn and In were within experimental error of the recommended BNL values. The absorption cross section for As is in good agreement with a recently published value for the activation cross section. The value for the resonance integral of As, derived from the present measurements, is in better agreement with calculations from resonance parameters than values reported earlier.
International Nuclear Information System (INIS)
Sokolowski, E.K.; Bladh, R.
1969-02-01
Pile oscillator measurements of heavy-water solutions of As, B, Mn and In have been carried out in two different neutron spectra in the R0 reactor. For B, Mn and In the 2200 m/s cross section values recommended in BNL-325 are given to within 1.5 % or less, while for As the stated uncertainty is 5 %. In the present work the BNL values for B, Mn and In were used to derive weighted mean calibration constants for the reactor, which were then in turn used for obtaining self-consistent cross section values for all four elements. The values thus obtained for B, Mn and In were within experimental error of the recommended BNL values. The absorption cross section for As is in good agreement with a recently published value for the activation cross section. The value for the resonance integral of As, derived from the present measurements, is in better agreement with calculations from resonance parameters than values reported earlier
Zero-range effective field theory for resonant wino dark matter. Part III. Annihilation effects
Braaten, Eric; Johnson, Evan; Zhang, Hong
2018-01-01
Near a critical value of the wino mass where there is a zero-energy S-wave resonance at the neutral-wino-pair threshold, low-energy winos can be described by a zero-range effective field theory (ZREFT) in which the winos interact nonperturbatively through a contact interaction and through Coulomb interactions. The effects of wino-pair annihilation into electroweak gauge bosons are taken into account through the analytic continuation of the real parameters for the contact interaction to comple...
DEZEST, Denis; MATHIEU, Fabrice; MAZENQ, Laurent; SOYER, Caroline; COSTECALDE, Jean; REMIENS, Denis; THOMAS, Olivier; DEÜ, Jean-François; NICU, Liviu
2013-01-01
In this work, we demonstrate the integration of piezoelectric actuation means on arrays of nanocantilevers at the wafer scale. We use lead titanate zirconate (PZT) as piezoelectric material mainly because of its excellent actuation properties even when geometrically constrained at extreme scale
Spin measurements for 147Sm+n resonances: Further evidence for nonstatistical effects
International Nuclear Information System (INIS)
Koehler, P. E.; Ullmann, J. L.; Bredeweg, T. A.; O'Donnell, J. M.; Reifarth, R.; Rundberg, R. S.; Vieira, D. J.; Wouters, J. M.
2007-01-01
We have determined the spins J of resonances in the 147 Sm(n,γ) reaction by measuring multiplicities of γ-ray cascades following neutron capture. Using this technique, we were able to determine J values for all but 14 of the 141 known resonances below E n =1 keV, including 41 firm J assignments for resonances whose spins previously were either unknown or tentative. These new spin assignments, together with previously determined resonance parameters, allowed us to extract level spacings (D 0,3 =11.76±0.93 and D 0,4 =11.21±0.85 eV) and neutron strength functions (10 4 S 0,3 =4.70±0.91 and 10 4 S 0,4 =4.93±0.92) for J=3 and 4 resonances, respectively. Furthermore, cumulative numbers of resonances and cumulative reduced neutron widths as functions of resonance energy indicate that very few resonances of either spin have been missed below E n =700 eV. This conclusion is strengthened by the facts that, over this energy range, Wigner distributions calculated using these D 0 values agree with the measured nearest-neighbor level spacings to within the experimental uncertainties, and that the Δ 3 values calculated from the data also agree with the expected values. Because a nonstatistical effect recently was reported near E n =350 eV from an analysis of 147 Sm(n,α) data, we divided the data into two regions; 0 n n n 0 distribution for resonances below 350 eV is consistent with the expected Porter-Thomas distribution. However, we found that Γ n 0 data in the 350 n 2 distribution having ν≥2 We discuss possible explanations for these observed nonstatistical effects and their possible relation to similar effects previously observed in other nuclides
Energy Technology Data Exchange (ETDEWEB)
Wang Shumin; Duyn, Jeff H [Laboratory of Functional and Molecular Imaging, National Institute of Neurological Disorders and Stroke, National Institutes of Health, 10 Center Drive, 10/B1D728, Bethesda, MD 20892 (United States)
2006-06-21
We present the combined field integral equation (CFIE) method for analysing radio-frequency coil arrays in high-field magnetic resonance imaging (MRI). Three-dimensional models of coils and the human body were used to take into account the electromagnetic coupling. In the method of moments formulation, we applied triangular patches and the Rao-Wilton-Glisson basis functions to model arbitrarily shaped geometries. We first examined a rectangular loop coil to verify the CFIE method and also demonstrate its efficiency and accuracy. We then studied several eight-channel receive-only head coil arrays for 7.0 T SENSE functional MRI. Numerical results show that the signal dropout and the average SNR are two major concerns in SENSE coil array design. A good design should be a balance of these two factors.
Double resonance Raman effects in InN nanowires
Energy Technology Data Exchange (ETDEWEB)
Domenech-Amador, N.; Cusco, R.; Artus, L. [Institut Jaume Almera, Consell Superior d' Investigacions Cientifiques (CSIC), Lluis Sole i Sabaris s.n., Barcelona, Catalonia (Spain); Calarco, R. [Institute of Bio- and Nanosystems, Research Center Juelich GmbH, Juelich (Germany); Paul-Drude-Institut fuer Festkoerperelektronik, Berlin (Germany); Yamaguchi, T.; Nanishi, Y. [Faculty of Science and Engineering, Ritsumeikan University, Noji-Higashi, Kusatsu, Shiga 525-8577 (Japan)
2012-04-15
We study the excitation wavelength dependence of the Raman spectra of InN nanowires. The E{sub 1}(LO) phonon mode, which is detected in backscattering configuration because of light entering through lateral faces, exhibits an upward frequency shift that can be explained by Martin's double resonance. The E{sub 1} (LO)/E{sub 2}{sup h} intensity ratio increases with the excitation wavelength more rapidly than the A{sub 1}(LO)/E{sub 2}{sup h} ratio measured in InN thin films. (copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)
Depolarisation effects in resonance absorption neutron polarising filters
International Nuclear Information System (INIS)
Mayers, J.
1982-06-01
The depolarisation of a neutron beam passing through a system of magnetically misaligned single domain particles is examined and simulated using a Monte-Carlo programme. The results of the simulations are in excellent agreement with those of analytic calculations within the regimes where such calculations are applicable. The simulations have been used in the estimation of the polarising efficiency and transmittance of a resonance absorption filter containing partially aligned particles of SmCo 5 . It is shown that the application of strong magnetic fields (approximately equal to 2T) should significantly improve the filter performance. A method of measuring this improvement is suggested. (author)
Magnetic resonance annual 1986
International Nuclear Information System (INIS)
Kressel, H.Y.
1986-01-01
This book contains papers written on magnetic resonance during 1986. Topics include: musculosketetal magnetic resonance imaging; imaging of the spine; magnetic resonance chemical shift imaging; magnetic resonance imaging in the central nervous system; comparison to computed tomography; high resolution magnetic resonance imaging using surface coils; magnetic resonance imaging of the chest; magnetic resonance imaging of the breast; magnetic resonance imaging of the liver; magnetic resonance spectroscopy of neoplasms; blood flow effects in magnetic resonance imaging; and current and potential applications of clinical sodium magnetic resonance imaging
Alfarsi, Anas; Dillon, Amy; McSweeney, Seán; Krüse, Jacob; Griffin, Brendan; Devine, Ken; Sherry, Patricia; Henken, Stephan; Fitzpatrick, Stephen; Fitzpatrick, Dara
2018-04-12
There are no rapid dissolution based tests for determining coating thickness, integrity and drug concentration in controlled release pellets either during production or post-production. The manufacture of pellets requires several coating steps depending on the formulation. The sub-coating and enteric coating steps typically take up to six hours each followed by additional drying steps. Post production regulatory dissolution testing also takes up to six hours to determine if the batch can be released for commercial sale. The thickness of the enteric coating is a key factor that determines the release rate of the drug in the gastro-intestinal tract. Also, the amount of drug per unit mass decreases with increasing thickness of the enteric coating. In this study, the coating process is tracked from start to finish on an hourly basis by taking samples of pellets during production and testing those using BARDS (Broadband Acoustic Resonance Dissolution Spectroscopy). BARDS offers a rapid approach to characterising enteric coatings with measurements based on reproducible changes in the compressibility of a solvent due to the evolution of air during dissolution. This is monitored acoustically via associated changes in the frequency of induced acoustic resonances. A steady state acoustic lag time is associated with the disintegration of the enteric coatings in basic solution. This lag time is pH dependent and is indicative of the rate at which the coating layer dissolves. BARDS represents a possible future surrogate test for conventional USP dissolution testing as its data correlates directly with the thickness of the enteric coating, its integrity and also with the drug loading as validated by HPLC. Copyright © 2018 Elsevier B.V. All rights reserved.
On-resonance deformation effect measurements: A probe of order within chaos in the nucleus
International Nuclear Information System (INIS)
Davis, E.D.; Gould, C.R.; Gould, C.R.
1998-01-01
The statistics of on-resonance measurements of the deformation effect cross section σ 02 in unpolarized neutron transmission through an aligned 165 Ho target is discussed. Under the standard Porter-Thomas assumption about reduced partial width amplitudes, the sign of σ 02 is random at s-wave resonances with d-wave admixtures. Motivated by the observation of sign correlations in epithermal parity-violation studies, conditions under which a doorway state will give rise to σ 02 close-quote s of nonrandom sign are identified. Oblate shape isomers lying at excitation energies in the isolated resonance regime could meet these conditions. copyright 1998 The American Physical Society
Zakharchenko, K V; Kuznetsov, M B; Chistyakov, A A; Karavanskij, V A
2001-01-01
One studies the effect of resonance radiation-free transfer of electronic excitation between silicon nanocrystals and iodine molecules sorbed in pores. The experiment procedure includes laser-induced luminescence and laser desorption mass spectrometry. One analyzes photoluminescence spectra prior to and upon iodine sorption. Excitation of iodine through the mechanism of resonance transfer is determined to result in desorption of the iodine sorbed molecules with relatively high kinetic energies (3-1 eV). One evaluated the peculiar distance of resonance transfer the approximate value of which was equal to 2 nm
Resonance effects of transition radiation emitted from thin foil stacks using electron beam
Energy Technology Data Exchange (ETDEWEB)
Awata, Takaaki; Yajima, Kazuaki; Tanaka, Takashi [Kyoto Univ. (Japan). Faculty of Engineering; and others
1997-03-01
Transition Radiation(TR) X rays are expected to be a high brilliant X-ray source because the interference among TR X rays emitted from many thin foils placed periodically in vacuum can increase their intensity and make them quasi-monochromatic. In order to study the interference (resonance) effects of TR, we measured the energy spectra of TR for several sets of thin-foil stacks at various emission angles. It was found that the resonance effects of TR are classified into intrafoil and interfoil resonances and the intensity of TR X rays increases nonlinearly with increasing foil number, attributing to the interfoil resonance. It became evident that the brilliance of TR is as high as that of SR. (author)
Effect of inhomogeneous temperature fields on acoustic streaming structures in resonators.
Červenka, Milan; Bednařík, Michal
2017-06-01
Acoustic streaming in 2D rectangular resonant channels filled with a fluid with a spatial temperature distribution is studied within this work. An inertial force is assumed for driving the acoustic field; the temperature inhomogeneity is introduced by resonator walls with prescribed temperature distribution. The method of successive approximations is employed to derive linear equations for calculation of primary acoustic and time-averaged secondary fields including the streaming velocity. The model equations have a standard form which allows their numerical integration using a universal solver; in this case, COMSOL Multiphysics was employed. The numerical results show that fluid temperature variations in the direction perpendicular to the resonator axis influence strongly the streaming field if the ratio of the channel width and the viscous boundary layer thickness is big enough; the streaming in the Rayleigh vortices can be supported as well as opposed, which can ultimately lead to the appearance of additional vortices.
Verginadis, Ioannis I; Simos, Yannis V; Velalopoulou, Anastasia P; Vadalouca, Athina N; Kalfakakou, Vicky P; Karkabounas, Spyridon Ch; Evangelou, Angelos M
2012-12-01
Exposure to various types of electromagnetic fields (EMFs) affects pain specificity (nociception) and pain inhibition (analgesia). Previous study of ours has shown that exposure to the resonant spectra derived from biologically active substances' NMR may induce to live targets the same effects as the substances themselves. The purpose of this study is to investigate the potential analgesic effect of the resonant EMFs derived from the NMR spectrum of morphine. Twenty five Wistar rats were divided into five groups: control group; intraperitoneal administration of morphine 10 mg/kg body wt; exposure of rats to resonant EMFs of morphine; exposure of rats to randomly selected non resonant EMFs; and intraperitoneal administration of naloxone and simultaneous exposure of rats to the resonant EMFs of morphine. Tail Flick and Hot Plate tests were performed for estimation of the latency time. Results showed that rats exposed to NMR spectrum of morphine induced a significant increase in latency time at time points (p spectrum of morphine. Our results indicate that exposure of rats to the resonant EMFs derived from the NMR spectrum of morphine may exert on animals similar analgesic effects to morphine itself.
Effect of the Potential Shape on the Stochastic Resonance Processes
Kenmoé, G. Djuidjé; Ngouongo, Y. J. Wadop; Kofané, T. C.
2015-10-01
The stochastic resonance (SR) induced by periodic signal and white noises in a periodic nonsinusoidal potential is investigated. This phenomenon is studied as a function of the friction coefficient as well as the shape of the potential. It is done through an investigation of the hysteresis loop area which is equivalent to the input energy lost by the system to the environment per period of the external force. SR is evident in some range of the shape parameter of the potential, but cannot be observed in the other range. Specially, variation of the shape potential affects significantly and not trivially the heigh of the potential barrier in the Kramers rate as well as the occurrence of SR. The finding results show crucial dependence of the temperature of occurrence of SR on the shape of the potential. It is noted that the maximum of the input energy generally decreases when the friction coefficient is increased.
Energy Technology Data Exchange (ETDEWEB)
Parra, Jorge O.; Hackert, Chris L.; Collier, Hughbert A.; Bennett, Michael
2002-01-29
The objective of this project was to develop an advanced imaging method, including pore scale imaging, to integrate NMR techniques and acoustic measurements to improve predictability of the pay zone in hydrocarbon reservoirs. This is accomplished by extracting the fluid property parameters using NMR laboratory measurements and the elastic parameters of the rock matrix from acoustic measurements to create poroelastic models of different parts of the reservoir. Laboratory measurement techniques and core imaging are being linked with a balanced petrographical analysis of the core and theoretical model.
Synchrotron oscillation effects on an rf-solenoid spin resonance
Benati, P.; Chiladze, D.; Dietrich, J.; Gaisser, M.; Gebel, R.; Guidoboni, G.; Hejny, V.; Kacharava, A.; Kamerdzhiev, V.; Kulessa, P.; Lehrach, A.; Lenisa, P.; Lorentz, B.; Maier, R.; Mchedlishvili, D.; Morse, W. M.; Öllers, D.; Pesce, A.; Polyanskiy, A.; Prasuhn, D.; Rathmann, F.; Semertzidis, Y. K.; Stephenson, E. J.; Stockhorst, H.; Ströher, H.; Talman, R.; Valdau, Yu.; Weidemann, Ch.; Wüstner, P.
2012-12-01
New measurements are reported for the time dependence of the vertical polarization of a 0.97GeV/c deuteron beam circulating in a storage ring and perturbed by an rf solenoid. The storage ring is the cooler synchrotron (COSY) located at the Forschungszentrum Jülich. The beam polarization was measured continuously using a 1.5 cm thick carbon target located at the edge of the circulating deuteron beam and the scintillators of the EDDA detector. An rf solenoid mounted on the ring was used to generate fields at and near the frequency of the 1-Gγ spin resonance. Measurements were made of the vertical beam polarization as a function of time with the operation of the rf solenoid in either fixed or continuously variable frequency mode. Using rf-solenoid strengths as large as 2.66×10-5revolutions/turn, slow oscillations (˜1Hz) were observed in the vertical beam polarization. When the circulating beam was continuously electron cooled, these oscillations completely reversed the polarization and showed no sign of diminishing in amplitude. But for the uncooled beam, the oscillation amplitude was damped to nearly zero within a few seconds. A simple spin-tracking model without the details of the COSY ring lattice was successful in reproducing these oscillations and demonstrating the sensitivity of the damping to the magnitude of the synchrotron motion of the beam particles. The model demonstrates that the characteristic features of measurements made in the presence of large synchrotron oscillations are distinct from the features of such measurements when made off resonance. These data were collected in preparation for a study of the spin coherence time, a beam property that needs to become long to enable a search for an electric dipole moment using a storage ring.
Spin-wave resonance in magnetic films in conditions of skin effect
International Nuclear Information System (INIS)
Nosov, R.N.; Sementsov, D.I.
2002-01-01
The effect of the finite depth of the high-frequency field penetration into the ferromagnetic metal on the spin-wave resonance spectrum perpendicular to the magnetized layer with different types of the spins surface fixation and by availability of attenuation in the spin system is studied. The exact numerical solution of the magnetization motion equation with an account of the skin-layer finite thickness is obtained. The change in the form of the resonance curve on the frequencies close to the frequency of the ferromagnetic resonance is identified in the case of essentially nonuniform high-frequency field distribution by the layer thickness along with widening and decreasing in the amplitude of all resonance peaks [ru
Modeling and understanding of effects of randomness in arrays of resonant meta-atoms
DEFF Research Database (Denmark)
Tretyakov, Sergei A.; Albooyeh, Mohammad; Alitalo, Pekka
2013-01-01
In this review presentation we will discuss approaches to modeling and understanding electromagnetic properties of 2D and 3D lattices of small resonant particles (meta-atoms) in transition from regular (periodic) to random (amorphous) states. Nanostructured metasurfaces (2D) and metamaterials (3D......) are arrangements of optically small but resonant particles (meta-atoms). We will present our results on analytical modeling of metasurfaces with periodical and random arrangements of electrically and magnetically resonant meta-atoms with identical or random sizes, both for the normal and oblique-angle excitations....... We show how the electromagnetic response of metasurfaces is related to the statistical parameters of the structure. Furthermore, we will discuss the phenomenon of anti-resonance in extracted effective parameters of metamaterials and clarify its relation to the periodicity (or amorphous nature...
Shared or Integrated: Which Type of Integration is More Effective Improves Students’ Creativity?
Mariyam, M.; Kaniawati, I.; Sriyati, S.
2017-09-01
Integrated science learning has various types of integration. This study aims to apply shared and integrated type of integration with project based learning (PjBL) model to improve students’ creativity on waste recycling theme. The research method used is a quasi experiment with the matching-only pre test-post test design. The samples of this study are 108 students consisting of 36 students (experiment class 1st), 35 students (experiment class 2nd) and 37 students (control class 3rd) at one of Junior High School in Tanggamus, Lampung. The results show that there is difference of creativity improvement in the class applied by PjBL model with shared type of integration, integrated type of integration and without any integration in waste recycling theme. Class applied by PjBL model with shared type of integration has the higher creativity improvement than the PjBL model with integrated type of integration and without any integration. Integrated science learning using shared type only combines 2 lessons, hence an intact concept is resulted. So, PjBL model with shared type of integration more effective improves students’ creativity than integrated type.
Gómez Rodríguez, Rafael Ángel
2014-01-01
To say that someone possesses integrity is to claim that that person is almost predictable about responses to specific situations, that he or she can prudentially judge and to act correctly. There is a closed interrelationship between integrity and autonomy, and the autonomy rests on the deeper moral claim of all humans to integrity of the person. Integrity has two senses of significance for medical ethic: one sense refers to the integrity of the person in the bodily, psychosocial and intellectual elements; and in the second sense, the integrity is the virtue. Another facet of integrity of the person is la integrity of values we cherish and espouse. The physician must be a person of integrity if the integrity of the patient is to be safeguarded. The autonomy has reduced the violations in the past, but the character and virtues of the physician are the ultimate safeguard of autonomy of patient. A field very important in medicine is the scientific research. It is the character of the investigator that determines the moral quality of research. The problem arises when legitimate self-interests are replaced by selfish, particularly when human subjects are involved. The final safeguard of moral quality of research is the character and conscience of the investigator. Teaching must be relevant in the scientific field, but the most effective way to teach virtue ethics is through the example of the a respected scientist.
International Nuclear Information System (INIS)
Romaneehsen, B.; Oberholzer, K.; Kreitner, K.-F.; Mueller, L.P.
2003-01-01
Purpose: To investigate the feasibility of using multiple receiver coil elements for time saving integrated parallel imaging techniques (iPAT) in traumatic musculoskeletal disorders. Material and methods: 6 patients with traumatic derangements of the knee, ankle and hip underwent MR imaging at 1.5 T. For signal detection of the knee and ankle, we used a 6-channel body array coil that was placed around the joints, for hip imaging two 4-channel body array coils and two elements of the spine array coil were combined for signal detection. All patients were investigated with a standard imaging protocol that mainly consisted of different turbo spin-echo sequences (PD-, T 2 -weighted TSE with and without fat suppression, STIR). All sequences were repeated with an integrated parallel acquisition technique (iPAT) using a modified sensitivity encoding (mSENSE) technique with an acceleration factor of 2. Overall image quality was subjectively assessed using a five-point scale as well as the ability for detection of pathologic findings. Results: Regarding overall image quality, there were no significant differences between standard imaging and imaging using mSENSE. All pathologies (occult fracture, meniscal tear, torn and interpositioned Hoffa's cleft, cartilage damage) were detected by both techniques. iPAT led to a 48% reduction of acquisition time compared with standard technique. Additionally, time savings with iPAT led to a decrease of pain-induced motion artifacts in two cases. Conclusion: In times of increasing cost pressure, iPAT using multiple coil elements seems to be an efficient and economic tool for fast musculoskeletal imaging with diagnostic performance comparable to conventional techniques. (orig.) [de
Hu, Liang-sheng; Fong, Chi-Chun; Zou, Lan; Wong, Wing-Leung; Wong, Kwok-Yin; Wu, Rudolf S S; Yang, Mengsu
2014-03-15
A piezoelectric biosensor for detection of endocrine disrupting chemicals (EDCs) was developed by incorporating chemical/biochemical recognition elements on the ceramic resonator surface for competitive binding assays. A facile electrodeposition was employed to modify the sensor surface with Au nanoparticles, which increased the surface area and enhanced the binding capacity of the immobilized probes. Thiol-labeled long chain hydrocarbon with bisphenol A (BPA) as head group was synthesized and self-assembled on the Au nanoparticle surface as the sensing probes, which showed a linear response upon the binding of estrogen receptor (ER-α) ranging from 1 to 30 nM. Detection of estrone, 17β-estradiol and BPA was achieved by integrating a competitive binding assay with the piezoelectric sensor. In this detection scheme, different concentrations of EDCs were incubated with 30 nM of ER-α, and the un-bounded ER-α in the solution was captured by the probes immobilized on the ceramic resonator, which resulted in the frequency changes for different EDCs. The biosensor assay exhibited a linear response to EDCs with a low detection limit of 2.4-2.9 nM (S/N=3), and required only a small volume of sample (1.5 µl) with the assay time of 2h. The performance of the biosensor assay was also evaluated for rapid and facile determination of EDCs of environmental relevant concentrations in drinking water and seawater, and the recovery rate was in the range between 94.7% and 109.8%. © 2013 Elsevier B.V. All rights reserved.
International Nuclear Information System (INIS)
Aleksanyan, A.A.; Volchkov, N.A.; Dravin, V.A.; Kazakov, I.P.; Karuzskij, A.L.; Murzin, V.N.; Perestoronin, A.V.; Tskhovrebov, A.M.; Shmelev, S.S.
2014-01-01
Features of the effect of a subterahertz microwave field on the current characteristics of a resonant-tunneling diode in resonance systems with different configurations have been studied. Changes in the current characteristics of the resonant-tunneling diode under variation of the electrophysical parameters of dielectric and microstrip resonators, in particular high-Q-factor superconducting microstrip resonators, have been experimentally studied and analyzed [ru
Schaffer, L.; Burns, J. A.
1995-01-01
Dust grains in planetary rings acquire stochastically fluctuating electric charges as they orbit through any corotating magnetospheric plasma. Here we investigate the nature of this stochastic charging and calculate its effect on the Lorentz resonance (LR). First we model grain charging as a Markov process, where the transition probabilities are identified as the ensemble-averaged charging fluxes due to plasma pickup and photoemission. We determine the distribution function P(t;N), giving the probability that a grain has N excess charges at time t. The autocorrelation function tau(sub q) for the strochastic charge process can be approximated by a Fokker-Planck treatment of the evolution equations for P(t; N). We calculate the mean square response to the stochastic fluctuations in the Lorentz force. We find that transport in phase space is very small compared to the resonant increase in amplitudes due to the mean charge, over the timescale that the oscillator is resonantly pumped up. Therefore the stochastic charge variations cannot break the resonant interaction; locally, the Lorentz resonance is a robust mechanism for the shaping of etheral dust ring systems. Slightly stronger bounds on plasma parameters are required when we consider the longer transit times between Lorentz resonances.
Effect of an additional magnetic field on Hanle-type absorption resonances
International Nuclear Information System (INIS)
Singh Grewal, Raghwinder; Pattabiraman, M
2014-01-01
We computationally compare Hanle-type resonances for a F g =1→F e =0 transition of the 87 RbD 2 line for magnetic field scans parallel (longitudinal scan) and perpendicular (transverse scan) to the direction of propagation of the optical field in the presence of an additional transverse magnetic field (TMF). For a linearly polarized light, the coherent population trapping (CPT) resonances split at line centre and are identical for both longitudinal and transverse scans. When the probe beam ellipticity is varied, the effect of the TMF is found to be opposite for longitudinal and transverse scans. For a longitudinal scan, the splitting observed in the CPT resonance evolves into an enhanced absorption resonance with an increase in ellipticity. For a transverse scan, the splitting vanishes at higher ellipticities. This can be understood in terms of population redistribution in the ground state sublevels and near-neighbor ground state coherences created by the TMF. We also show that the enhanced absorption signal that splits the CPT resonance strongly depends on transit time, and the CPT resonance strength depends on the excited state dephasing rate. (paper)
Isoscalar giant resonances and Landau parameters with density-dependent effective interactions
International Nuclear Information System (INIS)
Kohno, Michio; Ando, Kazuhiko
1979-01-01
Discussion is given on the relations between the Landau parameters and the isoscalar giant (quadrupole- and monopole-) resonance energies by using general density-dependent interactions. In the limit of infinite nuclear matter, the isoscalar giant quadrupole energy is shown to depend not only on the effective mass but also on the Landau parameter F 2 . Collective energies of the isoscalar giant resonances are calculated for 16 O and 40 Ca with four different effective interactions, G-0, B1, SII and SV, by using the scaling- and constrained Hartree-Fock-methods. It is shown that the dependence of the collective energies on the effective interactions is essentially determined by the Landau parameters. The G-0 force is found to be most successful in reproducing the giant resonance energies. Validity of the RPA-moment theorems is examined for the case of local density-dependent interactions. (author)
Interference shake-up effects in the resonant Auger decay of krypton
International Nuclear Information System (INIS)
Lagutin, B.M.; Sukhorukov, V.L.; Petrov, I.D.; Demekhin, Ph.V.; Schartner, K.-H.; Ehresmann, A.; Schmoranzer, H.
2005-01-01
Parameters of the resonant 4p 4p -3dε-bar Auger effect (RA) following the 3d-n p (n=5,6) excitation in Kr were calculated with taking into account the interference between several resonant and direct non-resonant transition amplitudes. For the first time all individual lines of the extended RA spectrum which comprises both the 4p 4 ( 1 D) 5p and the 4p 4 ( 1 D) 6p groups of final ionic states were considered. It was revealed that each group contains individual lines where the interference contributions have different signs thus providing a weak interference effect on the average over the whole group. Interference effects are found to be more pronounced in the angular distribution of the RA products
International Nuclear Information System (INIS)
Moldauer, P.A.
1979-01-01
The main features of the effects of S-matrix flucturations on average cross sections are reviewed with emphasis on recent developments on the enhancement of small cross sections and cross sections between directly coupled channels. Examples are given in which the effect can distort the shape of a doorway state resonance so as to reduce its observed width. 4 figures
Investigation of ELM [edge localized mode] Dynamics with the Resonant Magnetic Perturbation Effects
Energy Technology Data Exchange (ETDEWEB)
Pankin, Alexei Y.; Kritz, Arnold H.
2011-07-19
Topics covered are: anomalous transport and E x B flow shear effects in the H-mode pedestal; RMP (resonant magnetic perturbation) effects in NSTX discharges; development of a scaling of H-mode pedestal in tokamak plasmas with type I ELMs (edge localized modes); and divertor heat load studies.
Investigation of ELM [edge localized mode] Dynamics with the Resonant Magnetic Perturbation Effects
International Nuclear Information System (INIS)
Pankin, Alexei Y.; Kritz, Arnold H.
2011-01-01
Topics covered are: anomalous transport and E f- B flow shear effects in the H-mode pedestal; RMP (resonant magnetic perturbation) effects in NSTX discharges; development of a scaling of H-mode pedestal in tokamak plasmas with type I ELMs (edge localized modes); and divertor heat load studies
International Nuclear Information System (INIS)
Collins, T.
1985-08-01
A simple criterion governs the beam distortion and/or loss of protons on a fast resonance crossing. Results from numerical integrations are illustrated for simple sextupole, octupole, and 10-pole resonances
Energy Technology Data Exchange (ETDEWEB)
Collins, T.
1985-08-01
A simple criterion governs the beam distortion and/or loss of protons on a fast resonance crossing. Results from numerical integrations are illustrated for simple sextupole, octupole, and 10-pole resonances.
Energy Technology Data Exchange (ETDEWEB)
Romaneehsen, B.; Oberholzer, K.; Kreitner, K.-F. [Johannes Gutenberg-Univ. Mainz (Germany). Klinik und Poliklinik fuer Radiologie; Mueller, L.P. [Johannes Gutenberg-Univ. Mainz (Germany). Klinik und Poliklinik fuer Unfallchirurgie
2003-09-01
Purpose: To investigate the feasibility of using multiple receiver coil elements for time saving integrated parallel imaging techniques (iPAT) in traumatic musculoskeletal disorders. Material and methods: 6 patients with traumatic derangements of the knee, ankle and hip underwent MR imaging at 1.5 T. For signal detection of the knee and ankle, we used a 6-channel body array coil that was placed around the joints, for hip imaging two 4-channel body array coils and two elements of the spine array coil were combined for signal detection. All patients were investigated with a standard imaging protocol that mainly consisted of different turbo spin-echo sequences (PD-, T{sub 2}-weighted TSE with and without fat suppression, STIR). All sequences were repeated with an integrated parallel acquisition technique (iPAT) using a modified sensitivity encoding (mSENSE) technique with an acceleration factor of 2. Overall image quality was subjectively assessed using a five-point scale as well as the ability for detection of pathologic findings. Results: Regarding overall image quality, there were no significant differences between standard imaging and imaging using mSENSE. All pathologies (occult fracture, meniscal tear, torn and interpositioned Hoffa's cleft, cartilage damage) were detected by both techniques. iPAT led to a 48% reduction of acquisition time compared with standard technique. Additionally, time savings with iPAT led to a decrease of pain-induced motion artifacts in two cases. Conclusion: In times of increasing cost pressure, iPAT using multiple coil elements seems to be an efficient and economic tool for fast musculoskeletal imaging with diagnostic performance comparable to conventional techniques. (orig.) [German] Ziel: Einsatz integrierter paralleler Akquisitionstechniken (iPAT) zur Verkuerzung der Untersuchungszeit bei muskuloskelettalen Verletzungen. Material und Methoden: 6 Patienten mit einem Knie, Sprunggelenks- oder Huefttrauma wurden bei 1,5 T
Radiation reaction effect on laser driven auto-resonant particle acceleration
International Nuclear Information System (INIS)
Sagar, Vikram; Sengupta, Sudip; Kaw, P. K.
2015-01-01
The effects of radiation reaction force on laser driven auto-resonant particle acceleration scheme are studied using Landau-Lifshitz equation of motion. These studies are carried out for both linear and circularly polarized laser fields in the presence of static axial magnetic field. From the parametric study, a radiation reaction dominated region has been identified in which the particle dynamics is greatly effected by this force. In the radiation reaction dominated region, the two significant effects on particle dynamics are seen, viz., (1) saturation in energy gain by the initially resonant particle and (2) net energy gain by an initially non-resonant particle which is caused due to resonance broadening. It has been further shown that with the relaxation of resonance condition and with optimum choice of parameters, this scheme may become competitive with the other present-day laser driven particle acceleration schemes. The quantum corrections to the Landau-Lifshitz equation of motion have also been taken into account. The difference in the energy gain estimates of the particle by the quantum corrected and classical Landau-Lifshitz equation is found to be insignificant for the present day as well as upcoming laser facilities
Integrated smartphone imaging of quantum dot photoluminescence and Förster resonance energy transfer
Petryayeva, Eleonora; Algar, W. Russ
2015-06-01
Smartphones and other mobile devices are emerging as promising analytical platforms for point-of-care diagnostics, particularly when combined with nanotechnology. For example, we have shown that the optical properties of semiconductor quantum dots (QDs) are well suited to photoluminescence (PL) detection with a smartphone camera. However, this previous work has utilized an external excitation source for interrogation of QD PL. In this proceeding, we demonstrate that the white-light LED photographic flashes built into smartphones can be optically filtered to yield blue light suitable for excitation of QD PL. Measurements were made by recording video with filtered flash illumination and averaging the frames of the video to obtain images with good signal-to-background ratios. These images permitted detection of green-emitting and red-emitting QDs at levels comparable to those possible with excitation using an external long-wave UV lamp. The optical properties of QDs proved to be uniquely suited to smartphone PL imaging, exhibiting emission that was 1-2 orders magnitude brighter than that of common fluorescent dyes under the same conditions. Excitation with the smartphone flash was also suitable for imaging of FRET between green-emitting QD donors and Alexa Fluor 555 (A555) fluorescent dye acceptors. No significant difference in FRET imaging capability was observed between excitation with the smartphone flash and a long-wave UV lamp. Although the smartphone flash did have some disadvantages compared to an external UV lamp, these disadvantages are potentially offset by the benefit of having excitation and detection integrated into the smartphone.
Integrating Technology: The Principals' Role and Effect
Machado, Lucas J.; Chung, Chia-Jung
2015-01-01
There are many factors that influence technology integration in the classroom such as teacher willingness, availability of hardware, and professional development of staff. Taking into account these elements, this paper describes research on technology integration with a focus on principals' attitudes. The role of the principal in classroom…
International Nuclear Information System (INIS)
Zhou, Changsong; Kurths, Juergen; Hu, Bambi
2001-01-01
We demonstrate the effect of coherence resonance in a heterogeneous array of coupled Fitz Hugh--Nagumo neurons. It is shown that coupling of such elements leads to a significantly stronger coherence compared to that of a single element. We report nontrivial effects of parameter heterogeneity and spatial independence of noise on array-enhanced coherence resonance; especially, we find that (i) the coherence increases as spatial correlation of the noise decreases, and (ii) inhomogeneity in the parameters of the array enhances the coherence. Our results have the implication that generic heterogeneity and background noise can play a constructive role to enhance the time precision of firing in neural systems
Single-top t-channel production with off-shell and non-resonant effects
Energy Technology Data Exchange (ETDEWEB)
Papanastasiou, A.S. [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Frederix, R. [CERN, Geneva (Switzerland). TH Unit; Frixione, S. [CERN, Geneva (Switzerland). TH Unit; ITPP, EPFL, Lausanne (Switzerland); Hirschi, V. [ITPP, EPFL, Lausanne (Switzerland); Maltoni, F. [Univ. Catholique de Louvain, Louvain-la-Neuve (Belgium). Centre of Cosmology, Particle Physics and Phenomenology
2013-05-15
This letter details and discusses the next-to-leading order QCD corrections to t-channel electro-weak W{sup +}bj production, where finite top-width effects are consistently taken into account. The computation is done within the aMC rate at NLO framework and includes both resonant and non-resonant contributions as well as interferences between the two. Results are presented for the LHC and compared to those of the narrow-width approximation and effective theory approaches.
Square well model and the functional form for the resonance integral
International Nuclear Information System (INIS)
Raina, V.; Srivastava, P.K.; Sane, K.V.
1975-01-01
It is shown that the relation β = eta(Z 1 Z 2 )/sup 1/2/ exp/broken bracket/ -X(Z 1 + Z 2 )R/broken bracket//R can be derived by assuming that the effective potential in π-electron systems can be approximated by a three-dimensional square well form. (U.S.)
International Nuclear Information System (INIS)
Tepikian, S.
1988-01-01
Siberian Snakes provide a practical means of obtaining polarized proton beams in large accelerators. The effect of snakes can be understood by studying the dynamics of spin precession in an accelerator with snakes and a single spin resonance. This leads to a new class of energy independent spin depolarizing resonances, called snake resonances. In designing a large accelerator with snakes to preserve the spin polarization, there is an added constraint on the choice of the vertical betatron tune due to the snake resonances. 11 refs., 4 figs
Energy Technology Data Exchange (ETDEWEB)
Rouben, D C
1997-11-28
A semiclassical method for resonant tunneling in a quantum well in the presence of a magnetic field tilted with regard to an electric field is developed. In particular a semiclassical formula is derived for the total current of electrons after the second barrier of the quantum well. The contribution of the stable and unstable orbits is studied. It appears that the parameters which describe the classical chaos in the quantum well have an important effect on the tunneling current. A numerical experiment is led, the contributions to the current of some particular orbits are evaluated and the results are compared with those given by the quantum theory. (A.C.) 70 refs.
Effects of pairing correlation on low-lying quasi-particle resonance in neutron drip-line nuclei
Kobayashi, Yoshihiko; Matsuo, Masayuki
2015-01-01
We discuss effects of pairing correlation on quasi-particle resonance. We analyze in detail how the width of low-lying quasi-particle resonance is governed by the pairing correlation in the neutron drip-line nuclei. We consider the 46Si + n system to discuss low-lying p wave quasi-particle resonance. Solving the Hartree-Fock-Bogoliubov equation in the coordinate space with scattering boundary condition, we calculate the phase shift, the elastic cross section, the resonance width and the reson...
CREATING EFFECTIVE MODELS OF VERTICAL INTEGRATED STRUCTURES IN UKRAINE
Directory of Open Access Journals (Sweden)
D. V. Koliesnikov
2011-01-01
Full Text Available The results of scientific research aimed at development of methodology-theoretical mechanisms of building the effective models of vertically-integrated structures are presented. A presence of vertically-integrated structures on natural-monopolistic markets at private and governmental sectors of economy and priority directions of integration are given.
Effect of vertical integration on the utilization of hardwood resources
Jan Wiedenbeck
2002-01-01
The effectiveness of vertical integration in promoting the efficient utilization of the hardwood resource in the eastern United States was assessed during a series of interviews with vertically integrated hardwood manufacturers in the Appalachian region. Data from 19 companies that responded to the 1996 phone survey indicate that: 1) vertically integrated hardwood...
Moix, Jeremy M; Ma, Jian; Cao, Jianshu
2015-03-07
A numerically exact path integral treatment of the absorption and emission spectra of open quantum systems is presented that requires only the straightforward solution of a stochastic differential equation. The approach converges rapidly enabling the calculation of spectra of large excitonic systems across the complete range of system parameters and for arbitrary bath spectral densities. With the numerically exact absorption and emission operators, one can also immediately compute energy transfer rates using the multi-chromophoric Förster resonant energy transfer formalism. Benchmark calculations on the emission spectra of two level systems are presented demonstrating the efficacy of the stochastic approach. This is followed by calculations of the energy transfer rates between two weakly coupled dimer systems as a function of temperature and system-bath coupling strength. It is shown that the recently developed hybrid cumulant expansion (see Paper II) is the only perturbative method capable of generating uniformly reliable energy transfer rates and emission spectra across a broad range of system parameters.
International Nuclear Information System (INIS)
Mannella, N.; Yang, S.-H.; Mun, B.S.; Garcia de Abajo, F.J.; Kay, A.W.; Sell, B.C.; Watanabe, M.; Ohldag, H.; Arenholz, E.; Young, A.T.; Hussain, Z.; Van Hove, M.A.; Fadley, C.S.
2006-01-01
We present experimental and theoretical results for the variation of the O 1s intensity from a NiO(001) surface as the excitation energy is varied through the Ni 2p1/2,3/2 absorption resonances, and as the incidence angle of the radiation is varied from grazing to larger values. For grazing incidence, a strong multi-atom resonant photoemission(MARPE) effect is seen on the O 1s intensity as the Ni 2p resonances are crossed, but its magnitude decreases rapidly as the incidence angle is increased. Resonant x-ray optical (RXRO) calculations are found to predict these effects very well, although the experimental effects are found to decrease at higher incidence angles faster than those in theory. The potential influence of photoelectron diffraction effects on such measurements are also considered, including experimental data with azimuthal-angle variation and corresponding multiple-scattering-diffraction calculations, but we conclude that they do not vary beyond what is expected on the basis of the change in photoelectron kinetic energy. Varying from linear polarization to circular polarization is found to enhance these effects in NiO considerably, although the reasons are not clear. We also discuss the relationship of these measurements to other related interatomic resonance experiments and theoretical developments, and make some suggestions for future studies in this area
Koval, L. R.
1978-01-01
In the context of the transmission of airborne noise into an aircraft fuselage, a mathematical model is presented for the effects of internal cavity resonances on sound transmission into a thin cylindrical shell. The 'noise reduction' of the cylinder is defined and computed, with and without including the effects of internal cavity resonances. As would be expected, the noise reduction in the absence of cavity resonances follows the same qualitative pattern as does transmission loss. Numerical results show that cavity resonances lead to wide fluctuations and a general decrease of noise reduction, especially at cavity resonances. Modest internal absorption is shown to greatly reduce the effect of cavity resonances. The effects of external airflow, internal cabin pressurization, and different acoustical properties inside and outside the cylinder are also included and briefly examined.
Huang, Pei-Nian; Xia, Sheng-Xuan; Fu, Guang-Lai; Liang, Mei-Zhen; Qin, Meng; Zhai, Xiang; Wang, Ling-Ling
2018-03-01
In this paper, we propose a structure composed of two graphene waveguides and dual coupled graphene ring resonators (GRRs) to achieve a plasmon-induced absorption (PIA) effect. A three-level plasmonic system and a temporal coupled mode theory (CMT) are utilized to verify the simulation results. Moreover, a double-window-PIA effect can be conveniently attained by introducing another GRR with proper parameters to meet more specific acquirement in optical modulation process. The pronounced PIA resonances can be tuned in a number of ways, such as by adjusting the coupling distance between the GRRs and the couplings between the GRR and the waveguide, and tuning the radius and the Fermi energy of the GRRs. Besides, the produced PIA effect shows a high group delay up to - 1 . 87 ps, exhibiting a particularly prominent fast-light feature. Our results have potential applications in the realization of THz-integrated spectral control and graphene plasmonic devices such as sensors, filters, ultra-fast optical switches and so on.
Hadronic atoms and ticklish nuclei: the E2 nuclear resonance effect
International Nuclear Information System (INIS)
Leon, M.
1975-06-01
The E2 nuclear resonance effect in hadronic atoms offers a way to increase the hadronic information that can be obtained from hadronic x-ray experiments. The effect occurs when an atomic deexcitation energy closely matches a nuclear excitation energy, so that some configuration mixing occurs. It shows up as an attenuation of some of the hadronic x-ray lines from a resonant versus a normal isotope target. The effect was observed very clearly in pionic cadmium in a recent LAMPF experiment. A planned LAMPF experiment will use the nuclear resonance effect to determine whether the p-wave π-nucleus interaction does indeed become repulsive for Z greater than or equal to 35 as predicted. The effect also appears in the kaonic molybdenum data taken at LBL because several of the stable molybdenum isotopes are resonant. A number of promising cases for π - , K - , anti p, and Σ - atoms are discussed and a spectacular and potentially very informative experiment on anti p- 100 Mo is proposed. (9 figures, 9 tables) (U.S.)
Resonant communicators, effective communicators. Communicator’s flow and credibility
Directory of Open Access Journals (Sweden)
Irene García-Ureta, Ph.D
2012-01-01
Full Text Available Communication studies have been integrating the latest developments in cognitive sciences and acknowledging the importance of understanding the subjective processes involved in communication. This article argues that communication studies should also take into account the psychology of the communicator. This article presents the theoretical basis and the results of a training programme designed for audiovisual communicators. The programme is based on the theories of self-efficacy and flow and seeks to improve students’ communication competencies through the use of presentation techniques and psychological skills to tackle communication apprehension. The programme involves an active methodology that is based on modelling, visualisation, immediate feedback and positive reinforcement. A repeated-measures ANOVA shows that the programme successfully decreases the level of communication apprehension, improves the perceived self-efficacy, improves the psychological state needed to perform better in front of the cameras (flow, and improves students’ communication skills. A path analysis proved that the perceived self-efficacy and anxiety levels predict the level of flow during the communication act. At the end of the training programme, those who experienced higher levels of flow and enjoyment during the communication task achieved higher quality levels in their communication exercise. It is concluded that the concepts of self-efficacy and flow facilitate advancing in the understanding of the factors that determine a communicator’s credibility and ability to connect with the audience.
Yebo, Nebiyu A; Lommens, Petra; Hens, Zeger; Baets, Roel
2010-05-24
Optical structures fabricated on silicon-on-insulator technology provide a convenient platform for the implementation of highly compact, versatile and low cost devices. In this work, we demonstrate the promise of this technology for integrated low power and low cost optical gas sensing. A room temperature ethanol vapor sensor is demonstrated using a ZnO nanoparticle film as a coating on an SOI micro-ring resonator of 5 microm in radius. The local coating on the ring resonators is prepared from colloidal suspensions of ZnO nanoparticles of around 3 nm diameter. The porous nature of the coating provides a large surface area for gas adsorption. The ZnO refractive index change upon vapor adsorption shifts the microring resonance through evanescent field interaction. Ethanol vapor concentrations down to 100 ppm are detected with this sensing configuration and a detection limit below 25 ppm is estimated.
Identification of anomalous Doppler resonance effect during current ramp down in HT-7 tokamak
Energy Technology Data Exchange (ETDEWEB)
Li Erzhong, E-mail: rzhonglee@ipp.ac.c [Institute of Plasma Physics, Chinese Academy of Science, Hefei 230031 (China); Hu Liqun; Ling Bili; Liu Yong; Ti Ang; Zhou Reijie; Lu Hongwei; Gao Xiang [Institute of Plasma Physics, Chinese Academy of Science, Hefei 230031 (China)
2010-09-21
The abrupt steep jump of electron cyclotron emission (ECE) signals during current ramp-down has been observed and explained by an anomalous Doppler resonance effect (ADR). The identifying process of ADR was presented based on the fast Fourier transform (FFT) technique. The threshold value for triggering a steep jump on ECE signals has been identified under different discharge conditions.
A novel nonlinear damage resonance intermodulation effect for structural health monitoring
Ciampa, Francesco; Scarselli, Gennaro; Meo, Michele
2017-04-01
This paper is aimed at developing a theoretical model able to predict the generation of nonlinear elastic effects associated to the interaction of ultrasonic waves with the steady-state nonlinear response of local defect resonance (LDR). The LDR effect is used in nonlinear elastic wave spectroscopy to enhance the excitation of the material damage at its local resonance, thus to dramatically increase the vibrational amplitude of material nonlinear phenomena. The main result of this work is to prove both analytically and experimentally the generation of novel nonlinear elastic wave effects, here named as nonlinear damage resonance intermodulation, which correspond to a nonlinear intermodulation between the driving frequency and the LDR one. Beside this intermodulation effect, other nonlinear elastic wave phenomena such as higher harmonics of the input frequency and superharmonics of LDR frequency were found. The analytical model relies on solving the nonlinear equation of motion governing bending displacement under the assumption of both quadratic and cubic nonlinear defect approximation. Experimental tests on a damaged composite laminate confirmed and validated these predictions and showed that using continuous periodic excitation, the nonlinear structural phenomena associated to LDR could also be featured at locations different from the damage resonance. These findings will provide new opportunities for material damage detection using nonlinear ultrasounds.
Investigation of (3, 3) resonance effects on the properties of neutron ...
Indian Academy of Sciences (India)
Home; Journals; Pramana – Journal of Physics; Volume 76; Issue 4. Investigation of (3,3) resonance effects on the properties of neutron-rich double magic spherical ﬁnite nucleus, 132Sn, in the ground state and under compression. Mohammed H E Abu-Sei'leek. Volume 76 Issue 4 April 2011 pp 573-589 ...
Strawn, Jeffrey R.; Patel, Nick C.; Chu, Wen-Jang; Lee, Jing-Huei; Adler, Caleb M.; Kim, Mi Jung; Bryan, Holly S.; Alfieri, David C.; Welge, Jeffrey A.; Blom, Thomas J.; Nandagopal, Jayasree J.; Strakowski, Stephen M.; DelBello, Melissa P.
2012-01-01
Objectives: This study used proton magnetic resonance spectroscopy ([superscript 1]H MRS) to evaluate the in vivo effects of extended-release divalproex sodium on the glutamatergic system in adolescents with bipolar disorder, and to identify baseline neurochemical predictors of clinical remission. Method: Adolescents with bipolar disorder who were…
Directory of Open Access Journals (Sweden)
J. Aizpurua
2011-09-01
Full Text Available The sensitivity in surface enhanced infrared spectroscopy (SEIRS strongly depends on where the resonant excitation is spectrally located compared to the molecular vibration that is to be enhanced. In this contribution, we study the effect of coupling in the electromagnetic properties of 2D gold nanorod arrays in the IR. We also study the SEIRS activity of higher order resonant excitations in long nanoantennas to identify polaritonic signals of a supporting SiO2 layer with nanometer thickness (3 nm on a silicon substrate.
International Nuclear Information System (INIS)
Bora, B.; Bhuyan, H.; Favre, M.; Wyndham, E.; Chuaqui, H.; Kakati, M.
2011-01-01
Self-excited plasma series resonance is observed in low pressure capacitvely coupled radio frequency discharges as high-frequency oscillations superimposed on the normal radio frequency current. This high-frequency contribution to the radio frequency current is generated by a series resonance between the capacitive sheath and the inductive and resistive bulk plasma. In this report, we present an experimental method to measure the plasma series resonance in a capacitively coupled radio frequency argon plasma by modifying the homogeneous discharge model. The homogeneous discharge model is modified by introducing a correction factor to the plasma resistance. Plasma parameters are also calculated by considering the plasma series resonances effect. Experimental measurements show that the self-excitation of the plasma series resonance, which arises in capacitive discharge due to the nonlinear interaction of plasma bulk and sheath, significantly enhances both the Ohmic and stochastic heating. The experimentally measured total dissipation, which is the sum of the Ohmic and stochastic heating, is found to increase significantly with decreasing pressure.
International Nuclear Information System (INIS)
Uchiyama, Yuta; Morita, Ryo
2011-01-01
The power uprating of the nuclear power plant (NPP) is conducted in United States, EU countries and so on, and also is planned in Japan. However, the degradation phenomena such as flow-induced vibration and wall thinning may increase or expose in the power uprate condition. In U.S. NPP, the dryer had been damaged by high cycle fatigue due to acoustic-induced vibration under a 17% extended power uprating (EPU) condition. This is caused by acoustic resonance at the stub pipes of safety relief valves (SRVs) in the main steam lines (MSL). Increased velocity by uprating excites the pressure fluctuations and makes large amplitude resonance. To evaluate the acoustic resonance at the stub pipes of SRVs in actual BWR, it is necessary to clarify the acoustic characteristics in steam flow. Although there are several previous studies about acoustic resonance, most of them are not steam flow but air flow. Therefore in this study, to investigate the acoustic characteristics in steam flow, we conducted steam flow experiments in each dry and wet steam conditions, and also nearly saturated condition. We measured pressure fluctuation at the top of the single stub pipe and in main steam piping. As a result, acoustic resonance in dry steam flow could be evaluated as same as that in air flow. It is clarified that resonance amplitude of fluctuating pressure at the top of the stub pipe in wet steam was reduced to one-tenth compared with that in dry. (author)
Xiong, Caiqiao; Zhou, Xiaoyu; Zhang, Ning; Zhan, Lingpeng; Chen, Yongtai; Nie, Zongxiu
2016-02-01
The nonlinear harmonics within the ion motion are the fingerprint of the nonlinear fields. They are exclusively introduced by these nonlinear fields and are responsible to some specific nonlinear effects such as nonlinear resonance effect. In this article, the ion motion in the quadrupole field with a weak superimposed octopole component, described by the nonlinear Mathieu equation (NME), was studied by using the analytical harmonic balance (HB) method. Good accuracy of the HB method, which was comparable with that of the numerical fourth-order Runge-Kutta (4th RK), was achieved in the entire first stability region, except for the points at the stability boundary (i.e., β = 1) and at the nonlinear resonance condition (i.e., β = 0.5). Using the HB method, the nonlinear 3β harmonic series introduced by the octopole component and the resultant nonlinear resonance effect were characterized. At nonlinear resonance, obvious resonant peaks were observed in the nonlinear 3β series of ion motion, but were not found in the natural harmonics. In addition, both resonant excitation and absorption peaks could be observed, simultaneously. These are two unique features of the nonlinear resonance, distinguishing it from the normal resonance. Finally, an approximation equation was given to describe the corresponding working parameter, q nr , at nonlinear resonance. This equation can help avoid the sensitivity degradation due to the operation of ion traps at the nonlinear resonance condition.
Continuum Modeling of Inductor Hysteresis and Eddy Current Loss Effects in Resonant Circuits
Energy Technology Data Exchange (ETDEWEB)
Pries, Jason L. [ORNL; Tang, Lixin [ORNL; Burress, Timothy A. [ORNL
2017-10-01
This paper presents experimental validation of a high-fidelity toroid inductor modeling technique. The aim of this research is to accurately model the instantaneous magnetization state and core losses in ferromagnetic materials. Quasi–static hysteresis effects are captured using a Preisach model. Eddy currents are included by coupling the associated quasi-static Everett function to a simple finite element model representing the inductor cross sectional area. The modeling technique is validated against the nonlinear frequency response from two different series RLC resonant circuits using inductors made of electrical steel and soft ferrite. The method is shown to accurately model shifts in resonant frequency and quality factor. The technique also successfully predicts a discontinuity in the frequency response of the ferrite inductor resonant circuit.
Ozkaya, Efe; Yilmaz, Cetin
2017-02-01
The effect of eddy current damping on a novel locally resonant periodic structure is investigated. The frequency response characteristics are obtained by using a lumped parameter and a finite element model. In order to obtain wide band gaps at low frequencies, the periodic structure is optimized according to certain constraints, such as mass distribution in the unit cell, lower limit of the band gap, stiffness between the components in the unit cell, the size of magnets used for eddy current damping, and the number of unit cells in the periodic structure. Then, the locally resonant periodic structure with eddy current damping is manufactured and its experimental frequency response is obtained. The frequency response results obtained analytically, numerically and experimentally match quite well. The inclusion of eddy current damping to the periodic structure decreases amplitudes of resonance peaks without disturbing stop band width.
Nuclear effects in electron spin resonance of crystalline solids
International Nuclear Information System (INIS)
Ursu, I.; Nistor, S.V.
1976-01-01
A survey on the theory of paramagnetic ions in crystals is given. Some recent applications in which nuclear properties are studied by means of the ESR method are presented against this background. Finer effects in the hyperfine structure of ESR spectra, temperature dependance of the hyperfine coupling of S-state ions, observation of nuclear isotopic shift in ESR represent the applications discussed
Unexpected nonlinear effects and critical coupling in NbN superconducting microwave resonators
International Nuclear Information System (INIS)
Abdo, B.; Buks, E.
2004-01-01
Full Text:In this work, we have designed and fabricated several NbN superconducting stripline microwave resonators sputtered on sapphire substrates. The low temperature response exhibits strong and unexpected nonlinear effects, including sharp jumps as the frequency or poser are varied, frequency hysteresis loops changing direction as the input power is varied, and others. Contrary to some other superconducting resonators, a simple model of a one-dimensional Duffing resonator cannot account for the experimental results. Whereas the physical origin of the unusual nonlinear response of our samples remains an open question, our intensive experimental study of these effects under varying conditions provides some important insight. We consider a hypothesis according to which Josephson junctions forming weak links between the grains of the NbN are responsible for the observed behavior. We show that most of the experimental results are qualitatively consistent with such hypothesis. While revealing the underlying physics remains an outstanding challenge for future research, the utilization of the unusual nonlinear response for some novel applications is already demonstrated in the present work. In particular an operate the resonator as an inter modulation amplifier and find that the gain can be as high as 15 dB. To the best of our knowledge, inter modulation gain greater than unity has not been reported before in the scientific literature. In another application we demonstrate for the first time that the coupling between the resonator and its feed line can be made amplitude dependent. This novel mechanism allows us to tune the resonator into critical coupling conditions
Effects of Syriza movement on EU integration
Aksu, Ceyda
2017-01-01
Although establishing unity in Europe or creating an integrated Europe dates back to medieval ages as an idea, it has been accelerated through all attempts and scholar works in the period after World War II. But while the process of integration has not been completed yet, some new developments which may endanger the process have been emerging within European Union. Lately Syriza which took power in 25th of January 2015 became the focal point for the people living not only in Greece and Europe...
International Nuclear Information System (INIS)
Han Tong; Cui Shimin; Tong Xiaoguang; Liu Li; Xue Kai; Liu Meili; Liang Siquan; Zhang Yunting; Zhi Dashi
2011-01-01
Objective: To assess the value of three -dimensional visualization of functional brain tissue and the functional magnetic resonance imaging (fMRI)-integrated neuronavigation in the resection of brain tumor adjacent to motor cortex. Method: Sixty patients with tumor located in the central sulcus were enrolled. Thirty patients were randomly assigned to function group and 30 to control group. Patients in function group underwent fMRI to localize the functional brain tissues. Then the function information was transferred to the neurosurgical navigator. The patients in control group underwent surgery with navigation without function information. The therapeutic effect, excision rate. improvement of motor function, and survival quality during follow-up were analyzed. Result: All patients in function group were accomplished visualization of functional brain tissues and fMRI-integrated neuronavigation. The locations of tumors, central sulcus and motor cortex were marked during the operation. The fMRI -integrated information played a great role in both pre- and post-operation. Pre-operation: designing the location of the skin flap and window bone, determining the relationship between the tumor and motor cortex, and designing the pathway for the resection. Post- operation: real-time navigation of relationship between the tumor and motor cortex, assisting to localize the motor cortex using interoperation ultra-sound for correcting the displacement by the CSF outflow and collapsing tumor. The patients in the function group had better results than the patients in the control group in therapeutic effect (u=2.646, P=0.008), excision rate (χ = 7.200, P<0.01), improvement of motor function (u=2.231, P=0.026), and survival quality (KPS u c = 2.664, P=0.008; Zubrod -ECOG -WHO u c =2.135, P=0.033). Conclusions: Using preoperative three -dimensional visualization of cerebral function tissue and the fMRI-integrated neuronavigation technology, combining intraoperative accurate
Effect of resonant microwave power on a PIG ion source
International Nuclear Information System (INIS)
Brown, I.G.; Galvin, J.E.; Gavin, B.F.; MacGill, R.A.
1984-08-01
We have investigated the effect of applying microwave power at the electron cyclotron frequency on the characteristics of the ion beam extracted from a hot-cathode PIG ion source. No change was seen in the ion charge state distribution. A small but significant reduction in the beam noise level was seen, and it is possible that the technique may find application in situations where beam quiescence is important. 29 references, 2 figures
International Nuclear Information System (INIS)
Payne, M.G.; Miller, J.C.; Hart, R.C.; Garrett, W.R.
1991-01-01
We consider effects which occur when four-wave sum frequency generation and multiphoton ionization are induced by lasers tuned near a three-photon resonance and simultaneously near or at a dipole allowed four-photon resonance. In studies with unfocused laser beams, if the phase mismatch of the generated four-wave-mixing field is large and the related two-photon resonance for the absorption of a four-wave-mixing photon and a laser photon results in strong absorption of the four-wave-mixing field, a coherent cancellation occurs between the pumping of the resonance by two- and four-photon processes. This interference effect occurs when the first laser is tuned on either side of the three-photon resonance and |Δk rL |much-gt 1, where Δk r is the mismatch and L is the length of the path of the laser beams in the gas. With focused laser beams large differences occur between ionization with unidirectional beams and with counterpropagating laser beams when |Δk rb |much-gt 1, where b is the confocal parameter of the focused laser beams. Strong absorption of the four-wave-mixing field is shown not to be necessary for strong destructive interference with focused laser beams when the phase mismatch is large. This work also suggests an explanation for earlier experiments where the presence of a four-photon resonance enabled the generation of third-harmonic light in a positively dispersive wavelength region. We argue that this process can occur when the laser used to achieve the four-photon resonance is focused on the small z (z is the coordinate in the direction of propagation) side of the focal point of the laser responsible for the third-harmonic generation
Integrating Adult Learning and Technologies for Effective Education: Strategic Approaches
Wang, Victor C. X.
2010-01-01
As adult learners and educators pioneer the use of technology in the new century, attention has been focused on developing strategic approaches to effectively integrate adult learning and technology in different learning environments. "Integrating Adult Learning and Technologies for Effective Education: Strategic Approaches" provides innovative…
Effect of Integral Non-Linearity on Energy Calibration of ...
African Journals Online (AJOL)
The integral non-linearity (INL) of four spectroscopy systems, two integrated (A1 and A2) and two classical (B1 and B2) systems was determined using pulses from a random pulse generator. The effect of INL on the system's energy calibration was also determined. The effect is minimal in the classical system at high ...
Integrative Strategy for Effective Teaching of Density and Pressure in ...
African Journals Online (AJOL)
Integrative Strategy for Effective Teaching of Density and Pressure in Senior Secondary Schools: A Guide to Physics teachers. U Stephen, J T Mkpanang. Abstract. The problem of many teachers throughout the world is not what to teach but how to teach what. In this paper, integrative strategy for effective teaching of density ...
Effects of Integrating Peace Education in the Nigeria Education System
Olowo, Oluwatoyin Olusegun
2016-01-01
This paper attempted to investigate the effects of integrating Peace Education into Nigeria educational system. Four research questions were designed for the study. The researcher designed an instrument tagged: Questionnaire on effect of Integrating Peace Education (QEIPE). The entire population of two hundred respondents spread across Secondary…
Duckers, H.J.; Muller, H J; Verhaagen, J; Nicolay, K; Gispen, Willem Hendrik
Proton magnetic resonance imaging enables non-invasive monitoring of lesion formation in multiple sclerosis and has an important role in assessing the potential effects of therapy. T2-weighted and short tau inversion recovery magnetic resonance imaging were used to assess the effect of a
Uher, T; Vaneckova, M; Sormani, M P; Krasensky, J; Sobisek, L; Dusankova, J Blahova; Seidl, Z; Havrdova, E; Kalincik, T; Benedict, R H B; Horakova, D
2017-02-01
While impaired cognitive performance is common in multiple sclerosis (MS), it has been largely underdiagnosed. Here a magnetic resonance imaging (MRI) screening algorithm is proposed to identify patients at highest risk of cognitive impairment. The objective was to examine whether assessment of lesion burden together with whole brain atrophy on MRI improves our ability to identify cognitively impaired MS patients. Of the 1253 patients enrolled in the study, 1052 patients with all cognitive, volumetric MRI and clinical data available were included in the analysis. Brain MRI and neuropsychological assessment with the Brief International Cognitive Assessment for Multiple Sclerosis were performed. Multivariable logistic regression and individual prediction analysis were used to investigate the associations between MRI markers and cognitive impairment. The results of the primary analysis were validated at two subsequent time points (months 12 and 24). The prevalence of cognitive impairment was greater in patients with low brain parenchymal fraction (BPF) (3.5 ml) than in patients with high BPF (>0.85) and low T2-LV (patients predicted cognitive impairment with 83% specificity, 82% negative predictive value, 51% sensitivity and 75% overall accuracy. The risk of confirmed cognitive decline over the follow-up was greater in patients with high T2-LV (OR 2.1; 95% CI 1.1-3.8) and low BPF (OR 2.6; 95% CI 1.4-4.7). The integrated MRI assessment of lesion burden and brain atrophy may improve the stratification of MS patients who may benefit from cognitive assessment. © 2016 EAN.
Resonant shallow donor magnetopolaron effect in a GaAs/AlGaAs quantum dot in high magnetic fields
International Nuclear Information System (INIS)
Zhu Kadi.
1993-11-01
Resonant shallow donor magnetopolaron effect in a GaAs/AlGaAs quantum dot in high magnetic fields is investigated by the variational treatment. It is shown that both the cyclotron resonant frequency ω * c+ due to the 1s-p+ hydrogenic transition and the cyclotron resonant frequency ω * c- due to the 1s-p - hydrogenic transition increase with the decrease of the dot size. The cyclotron resonant frequency ω * c+ is always larger than the bulk LO-phonon frequency ω LO , while the cyclotron resonant frequency ω * c- is lower than ω LO for larger quantum dots (l 0 > 2.0.r 0 , r 0 is the polaron radius). The results also show that the Coulomb interaction effect on the resonant frequencies is significant. (author). 26 refs, 3 figs
Kaźmierczak, Andrzej; Dortu, Fabian; Giannone, Domenico; Bogaerts, Wim; Drouard, Emmanuel; Rojo-Romeo, Pedro; Gaffiot, Frederic
2009-10-01
We analyze a highly compact optical add-drop filter topology based on a pair of microdisk resonators and a bus waveguide intersection. The filter is further assessed on an integrated optical 4×4 network for optical on-chip communication. The proposed network structure, as compact as 50×50 μm, is fabricated in a CMOS-compatible process on a silicon-on-insulator (SOI) substrate. Finally, the experimental results demonstrate the proper operation of the fabricated devices.
Effect of difference between group constants processed by codes TIMS and ETOX on integral quantities
International Nuclear Information System (INIS)
Takano, Hideki; Ishiguro, Yukio; Matsui, Yasushi.
1978-06-01
Group constants of 235 U, 238 U, 239 Pu, 240 Pu and 241 Pu have been produced with the processing code TIMS using the evaluated nuclear data of JENDL-1. The temperature and composition dependent self-shielding factors have been calculated for the two cases with and without considering mutual interference resonant nuclei. By using the group constants set produced by the TIMS code, the integral quantities, i.e. multiplication factor, Na-void reactivity effect and Doppler reactivity effect, are calculated and compared with those calculated with the use of the cross sections set produced by the ETOX code to evaluate accuracy of the approximate calculation method in ETOX. There is much difference in self-shielding factor in each energy group between the two codes. For the fast reactor assemblies under study, however, the integral quantities calculated with these two sets are in good agreement with each other, because of eventual cancelation of errors. (auth.)
Wang, Xiaoxi; Lentine, Anthony; DeRose, Christopher; Starbuck, Andrew L; Trotter, Douglas; Pomerene, Andrew; Mookherjea, Shayan
2016-10-03
Tunable silicon microring resonators with small, integrated micro-heaters which exhibit a junction field effect were made using a conventional silicon-on-insulator (SOI) photonic foundry fabrication process. The design of the resistive tuning section in the microrings included a "pinched" p-n junction, which limited the current at higher voltages and inhibited damage even when driven by a pre-emphasized voltage waveform. Dual-ring filters were studied for both large (>4.9 THz) and small (850 GHz) free-spectral ranges. Thermal red-shifting was demonstrated with microsecond-scale time constants, e.g., a dual-ring filter was tuned over 25 nm in 0.6 μs 10%-90% transition time, and with efficiency of 3.2 μW/GHz.
Energy Technology Data Exchange (ETDEWEB)
Contente, A D; Rodrigues, C G; Kataoka, D; Silveira, E; Oliveira, Junior, G F.B. de; Gonzaga, J L [Companhia Energetica de Sao Paulo, SP (Brazil)
1992-12-31
The problem caused by partial resonance effect in the phase regulation winding in Taubate substation transformer bench is discussed. Studies and decisions taken to use capacitors on tertiary winding of the transformers set, are presented. Damages caused by resonance on transformer contacts, studies and assays made to solve the problem, resonance frequency measured, and capacitors values calculation, are also shown 3 refs., 3 figs., 2 tabs.
Directory of Open Access Journals (Sweden)
Yunshun Zhang
2016-10-01
Full Text Available The collection of clean power from ambient vibrations is considered a promising method for energy harvesting. For the case of wheel rotation, the present study investigates the effectiveness of a piezoelectric energy harvester, with the application of stochastic resonance to optimize the efficiency of energy harvesting. It is hypothesized that when the wheel rotates at variable speeds, the energy harvester is subjected to on-road noise as ambient excitations and a tangentially acting gravity force as a periodic modulation force, which can stimulate stochastic resonance. The energy harvester was miniaturized with a bistable cantilever structure, and the on-road noise was measured for the implementation of a vibrator in an experimental setting. A validation experiment revealed that the harvesting system was optimized to capture power that was approximately 12 times that captured under only on-road noise excitation and 50 times that captured under only the periodic gravity force. Moreover, the investigation of up-sweep excitations with increasing rotational frequency confirmed that stochastic resonance is effective in optimizing the performance of the energy harvester, with a certain bandwidth of vehicle speeds. An actual-vehicle experiment validates that the prototype harvester using stochastic resonance is capable of improving power generation performance for practical tire application.
Interference effect as resonance killer of newly observed charmoniumlike states Y(4320) and Y(4390)
Energy Technology Data Exchange (ETDEWEB)
Chen, Dian-Yong [Southeast University, School of Physics, Nanjing (China); Liu, Xiang [Lanzhou University, School of Physical Science and Technology, Lanzhou (China); Lanzhou University, Research Center for Hadron and CSR Physics, Institute of Modern Physics of CAS, Lanzhou (China); Matsuki, Takayuki [Tokyo Kasei University, Tokyo (Japan); Nishina Center, RIKEN, Wako, Theoretical Research Division, Saitama (Japan)
2018-02-15
In this letter, we decode the newly observed charmoniumlike states, Y(4320) and Y(4390), by introducing interference effect between ψ(4160) and ψ(4415), which plays a role of resonance killer for Y(4320) and Y(4390). It means that two newly reported charmoniumlike states are not genuine resonances, according to which we can naturally explain why two well-established charmonia ψ(4160) and ψ(4415) are missing in the cross sections of e{sup +}e{sup -} → π{sup +}π{sup -}J/ψ and π{sup +}π{sup -}h{sub c} simultaneously. To well describe the detailed data of these cross sections around √(s) = 4.2 GeV, our study further illustrates that a charmoniumlike structure Y(4220) must be introduced. As a charmonium, Y(4220) should dominantly decay into its open-charm channel e{sup +}e{sup -} → D{sup 0}π{sup +}D{sup *-}, which provides an extra support to ψ(4S) assignment to Y(4220). In fact, this interference effect introduced to explain Y(4320) and Y(4390) gives a typical example of non-resonant explanations to the observed XYZ states, which should be paid more attention especially before identifying the observed XYZ states as genuine resonances. (orig.)
Noise-induced transitions and resonant effects in nonlinear systems
Zaikin, Alexei
2003-02-01
Our every-day experience is connected with different acoustical noise or music. Usually noise plays the role of nuisance in any communication and destroys any order in a system. Similar optical effects are known: strong snowing or raining decreases quality of a vision. In contrast to these situations noisy stimuli can also play a positive constructive role, e.g. a driver can be more concentrated in a presence of quiet music. Transmission processes in neural systems are of especial interest from this point of view: excitation or information will be transmitted only in the case if a signal overcomes a threshold. Dr. Alexei Zaikin from the Potsdam University studies noise-induced phenomena in nonlinear systems from a theoretical point of view. Especially he is interested in the processes, in which noise influences the behaviour of a system twice: if the intensity of noise is over a threshold, it induces some regular structure that will be synchronized with the behaviour of neighbour elements. To obtain such a system with a threshold one needs one more noise source. Dr. Zaikin has analyzed further examples of such doubly stochastic effects and developed a concept of these new phenomena. These theoretical findings are important, because such processes can play a crucial role in neurophysics, technical communication devices and living sciences. Unsere alltägliche Erfahrung ist mit verschiedenen akustischen Einfluessen wie Lärm, aber auch Musik verbunden. Jeder weiss, wie Lärm stören kann und Kommunikation behindert oder gar unterbindet. Ähnliche optische Effekte sind bekannt: starkes Schneetreiben oder Regengüsse verschlechtern die Sicht und lassen uns Umrisse nur noch schemenhaft erkennen. Jedoch koennen ähnliche Stimuli auch sehr positive Auswirkungen haben: Autofahrer fahren bei leiser Musik konzentrierter -- die Behauptung von Schulkindern, nur bei dröhnenden Bässen die Mathehausaufgaben richtig rechnen zu können, ist allerdings nicht wissenschaftlich
DEFF Research Database (Denmark)
Zhou, Leming; Zhou, Xiaoping; Chen, Yandong
2018-01-01
For the LCL-type grid-connected distributed generation system, the grid-current-feedback active damping (GCFAD) methods have a conflict between the resonance-suppression ability and harmonic-currents amplification. For this, an inverter-current-feedback reso-nance-suppression (ICFRS) method without...... additional sensors is proposed to reduce resonance-frequency offset and grid-inductance effect due to its unattenuated damping characteristic under high-frequency bandwidth. By analyzing two types of equivalent impedance models of ICFRS and GCFAD with a high-pass filter (HPF), GCFAD can suppress...
Directory of Open Access Journals (Sweden)
Fabienne Danhier
Full Text Available BACKGROUND: Paclitaxel (PTX is a potent anti-cancer chemotherapeutic agent and is widely used in the treatments of solid tumors, particularly of the breast and ovaries. An effective and safe micellar formulation of PTX was used to administer higher doses of PTX than Taxol® (the current commercialized drug. We hypothesize that PTX-loaded micelles (M-PTX may enhance tumor radiosensitivity by increasing the tumor oxygenation (pO(2. Our goals were (i to evaluate the contribution of the "oxygen effect" to the radiosensitizing effect of PTX; (ii to demonstrate the therapeutic relevance of the combination of M-PTX and irradiation and (iii to investigate the underlying mechanisms of the observed oxygen effect. METHODOLOGY AND PRINCIPAL FINDINGS: We used (PEG-p-(CL-co-TMC polymeric micelles to solubilize PTX. pO(2 was measured on TLT tumor-bearing mice treated with M-PTX (80 mg/kg using electron paramagnetic resonance (EPR oximetry. The regrowth delay following 10 Gy irradiation 24 h after M-PTX treatment was measured. The tumor perfusion was assessed by the patent blue staining. The oxygen consumption rate and the apoptosis were evaluated by EPR oximetry and the TUNEL assay, respectively. EPR oximetry experiments showed that M-PTX dramatically increases the pO(2 24 h post treatment. Regrowth delay assays demonstrated a synergy between M-PTX and irradiation. M-PTX increased the tumor blood flow while cells treated with M-PTX consumed less oxygen and presented more apoptosis. CONCLUSIONS: M-PTX improved the tumor oxygenation which leads to synergy between this treatment and irradiation. This increased pO(2 can be explained both by an increased blood flow and an inhibition of O(2 consumption.
International Nuclear Information System (INIS)
Segev, M.
1996-01-01
The last three years have witnessed an increasing interest in the in-rod distribution of resonance absorption and of temperature. High burnup, especially beyond the 'classical' limit of 30 GWd/T, is expected to generate uneven in-rod isotope distributions with consequences for fuel rod integrity and reactor Doppler feedback. There are recent indications that, even for a freshly loaded uranium-oxide rod, proper account of the U 238 in-rod absorption rate distribution results in a doppler coefficient some 15% lower in magnitude than its routinely calculated value. Presently a special form of application is made of the Bogart approach. This approach is based on the fact that, as a fuel rod is filled in from the outside, its resonance capture rate increases monotonically, despite file decreasing effective capture cross section for the thickness annulus. Bogart used His observation to derive a differential equation for the in-rod absorption distribution. Presently we capitalize on the idea in a discrete form. (author)
Energy Technology Data Exchange (ETDEWEB)
Segev, M [Ben-Gurion Univ. of the Negev, Beersheba (Israel). Dept. of Nuclear Engineering
1996-12-01
The last three years have witnessed an increasing interest in the in-rod distribution of resonance absorption and of temperature. High burnup, especially beyond the `classical` limit of 30 GWd/T, is expected to generate uneven in-rod isotope distributions with consequences for fuel rod integrity and reactor Doppler feedback. There are recent indications that, even for a freshly loaded uranium-oxide rod, proper account of the U{sup 238} in-rod absorption rate distribution results in a doppler coefficient some 15% lower in magnitude than its routinely calculated value. Presently a special form of application is made of the Bogart approach. This approach is based on the fact that, as a fuel rod is filled in from the outside, its resonance capture rate increases monotonically, despite file decreasing effective capture cross section for the thickness annulus. Bogart used His observation to derive a differential equation for the in-rod absorption distribution. Presently we capitalize on the idea in a discrete form. (author).
International Nuclear Information System (INIS)
Molnar, Levente; Barannikova, Olga; Wang, Fuqiang
2006-01-01
Statistical model fit to particle ratios in Au+Au collisions at RHIC suggests chemical freeze-out near phase transition boundary. Model interpretations of evolution from chemical to kinetic freeze-out vary. Results of the blast-wave fit to the STAR experimental data, where resonance contributions are not accounted for, suggest significant cooling and expansion between the freezeouts for central Au+Au collisions. Other models including resonances, argue for instant single freezeout with temperature close to the phase transition temperature. By combined thermal and blast-wave model parametrization including resonances, we systematically investigate the effect of resonance decays on the extracted kinetic freeze-out parameters. (authors)
DEFF Research Database (Denmark)
Ainsworth, A P; Rafaelsen, S R; Wamberg, P A
2004-01-01
BACKGROUND: It is not known whether initial endoscopic ultrasonography (EUS) or magnetic resonance cholangiopancreatography (MRCP) is more cost effective than endoscopic retrograde cholangiopancreatography (ERCP). METHODS: A cost-effectiveness analysis of EUS, MRCP and ERCP was performed on 163...
Observation of Resonant Effects in Ultracold Collisions between Heteronuclear Feshbach Molecules
Ye, Xin; Wang, Fudong; Zhu, Bing; Guo, Mingyang; Lu, Bo; Wang, Dajun
2016-05-01
Magnetic field dependent dimer-dimer collisional losses are studied with ultracold 23 Na87 Rb Feshbach molecules. By ramping the magnetic field across the 347.8 G inter-species Feshbach resonance and removing residual atoms with a magnetic field gradient, ~ 8000 pure NaRb Feshbach molecules with a temperature below 1 μK are produced. By holding the pure molecule sample in a crossed optical dipole trap and measuring the time-dependent loss curves under different magnetic fields near the Feshbach resonance, the dimer-dimer loss rates with respect to the atomic scattering length a are mapped out. We observe a resonant feature at around a = 600a0 and a rising tail at above a = 1600a0 . This behavior resembles previous theoretical works on homonuclear Feshbach molecule, where resonant effects between dimer-dimer collisions tied to tetramer bound states were predicted. Our work shows the possibility of exploring four-body physics within a heteronuclear system. We are supported by Hong Kong RGC General Research Fund no. CUHK403813.
Secondary resonances and the boundary of effective stability of Trojan motions
Páez, Rocío Isabel; Efthymiopoulos, Christos
2018-02-01
One of the most interesting features in the libration domain of co-orbital motions is the existence of secondary resonances. For some combinations of physical parameters, these resonances occupy a large fraction of the domain of stability and rule the dynamics within the stable tadpole region. In this work, we present an application of a recently introduced `basic Hamiltonian model' H_b for Trojan dynamics (Páez and Efthymiopoulos in Celest Mech Dyn Astron 121(2):139, 2015; Páez et al. in Celest Mech Dyn Astron 126:519, 2016): we show that the inner border of the secondary resonance of lowermost order, as defined by H_b, provides a good estimation of the region in phase space for which the orbits remain regular regardless of the orbital parameters of the system. The computation of this boundary is straightforward by combining a resonant normal form calculation in conjunction with an `asymmetric expansion' of the Hamiltonian around the libration points, which speeds up convergence. Applications to the determination of the effective stability domain for exoplanetary Trojans (planet-sized objects or asteroids) which may accompany giant exoplanets are discussed.
Resonance effects in projectile-electron loss in relativistic collisions with excited atoms
International Nuclear Information System (INIS)
Voitkiv, A B
2005-01-01
The theory of electron loss from projectile-ions in relativistic ion-atom collisions is extended to the case of collisions with excited atoms. The main feature of such collisions is a resonance which can emerge between electron transitions in the ion and atom. The resonance becomes possible due to the Doppler effect and has a well-defined impact energy threshold. In the resonance case, the ion-atom interaction is transmitted by the radiation field and the range of this interaction becomes extremely long. Because of this the presence of other atoms in the target medium and the size of the space occupied by the medium have to be taken into account and it turns out that microscopic loss cross sections may be strongly dependent on such macroscopic parameters as the target density, temperature and size. We consider both the total and differential loss cross sections and show that the resonance can have a strong impact on the angular and energy distributions of electrons emitted from the projectiles and the total number of electron loss events
Effect of polarization and focusing on laser pulse driven auto-resonant particle acceleration
International Nuclear Information System (INIS)
Sagar, Vikram; Sengupta, Sudip; Kaw, Predhiman
2014-01-01
The effect of laser polarization and focusing is theoretically studied on the final energy gain of a particle in the Auto-resonant acceleration scheme using a finite duration laser pulse with Gaussian shaped temporal envelope. The exact expressions for dynamical variables viz. position, momentum, and energy are obtained by analytically solving the relativistic equation of motion describing particle dynamics in the combined field of an elliptically polarized finite duration pulse and homogeneous static axial magnetic field. From the solutions, it is shown that for a given set of laser parameters viz. intensity and pulse length along with static magnetic field, the energy gain by a positively charged particle is maximum for a right circularly polarized laser pulse. Further, a new scheme is proposed for particle acceleration by subjecting it to the combined field of a focused finite duration laser pulse and static axial magnetic field. In this scheme, the particle is initially accelerated by the focused laser field, which drives the non-resonant particle to second stage of acceleration by cyclotron Auto-resonance. The new scheme is found to be efficient over two individual schemes, i.e., auto-resonant acceleration and direct acceleration by focused laser field, as significant particle acceleration can be achieved at one order lesser values of static axial magnetic field and laser intensity
Interference shake-up effects in the resonant Auger decay of krypton
International Nuclear Information System (INIS)
Lagutin, B.M.; Sukhorukov, V.L.; Petrov, I.D.; Demekhin, Ph.V.; Schartner, K.-H.; Ehresmann, A.; Schmoranzer, H.
2004-01-01
Full text: Recently it was shown that the resonant Auger effect (RA) has a complex multiple-pathway character. In particular, the intensities, I, of the two groups of lines in the RA spectrum of Kr corresponding to the 4p 4 ( 1 D)5pLSJ and the 4p 4 ( 1 D)6pLSJ final ionic states were measured as functions of the exciting-photon energy, E, at the two close-lying 3d -1 3/2 5p and 3d -1 5/2 6p resonance states. The experimental results were qualitatively interpreted within the frame of the two-levels model in which each group of the final ionic states was approximated as a single one. It was demonstrated that for both cases the I(E) dependence cannot be fitted as a sum of two Lorentzian curves corresponding to distinguishable transitions via the isolated 3d -1 3/2 5p or 3d -1 5/2 6p resonances. However, within the restrictions of the model, it was not possible to determine unambiguously the significance of each of the interfering partial resonant amplitudes as well as the direct non-resonant one. In the present work, for the first time, the ab initio calculation of the RA characteristics for each individual line of the Kr RA spectrum was performed with taking into account the interference between many resonant and direct non-resonant transition amplitudes. It was shown that in each of the above groups there is a line(or lines) for which the sign (destructive or constructive) of the interference of the partial amplitude is opposite to that one estimated in the two-levels model. This means that the studied RA decay is more complex than was suggested in. It is theoretically predicted that the interference effects would be more pronounced in the angular distribution of the products of the RA photoionization of which future measurements are desirable
Theory of Electric-Field Effects on Electron-Spin-Resonance Hyperfine Couplings
International Nuclear Information System (INIS)
Karna, S.P.
1997-01-01
A quantum mechanical theory of the effects of a uniform electric field on electron-spin-resonance hyperfine couplings is presented. The electric-field effects are described in terms of perturbation coefficients which can be used to probe the local symmetry as well as the strength of the electric field at paramagnetic sites in a solid. Results are presented for the first-order perturbation coefficients describing the Bloembergen effect (linear electric-field effect on hyperfine coupling tensor) for the O atom and the OH radical. copyright 1997 The American Physical Society
Directory of Open Access Journals (Sweden)
Matthias C. Krantz
2013-05-01
Full Text Available Resonant bending-mode magnetoelectric (ME coefficients of magnetostrictive-piezoelectric multilayer cantilevers are calculated analytically using a model developed for arbitrary multilayers on a substrate. Without quality factor effects the ME coefficient maxima in the four-dimensional parameter space of layer numbers, layer sequences, piezoelectric volume fractions, and substrate thicknesses are found to be essentially constant for nonzero substrate thickness. Global maxima occur for bilayers without substrates. Vanishing magnetoelectric response regions result from voltage cancellation in piezoelectric layers or absence of bending-mode excitation. They are determined by the neutral plane position in the multilayer stack. With Q-factor effects dominated by viscous air damping ME coefficients strongly increase with cantilever thickness primarily due to increasing resonance frequencies. The results yield a layer specific prediction of ME coefficients, resonance frequencies, and Q-factors in arbitrary multilayers and thus distinction of linear-coupling and Q-factor effects from exchange interaction, interface, or nonlinear ME effects.
Challenge of Effective Technology Integration into Teaching and Learning
Ramorola, M. Z.
2013-01-01
South African teachers are faced with challenges in integrating technology effectively into a coherent framework at school level. There seems to be little evidence of technology integration into classroom activities such as systematic planning and implementation of lessons that require learners to think critically, work collaboratively, and use…
Poloidal field effects on fundamental minority ion cyclotron resonance heating in a tokamak plasma
International Nuclear Information System (INIS)
Jun, S. C.; Imre, Kaya; Stevens, D. C.; Weitzner, Harold; Chang, C. S.
2000-01-01
Minority ion fundamental cyclotron resonance is studied in a large tokamak in which the geometrical optics approximation applies off resonance and the minority average speed is less than the wave phase speeds. Poloidal equilibrium magnetic field effects are included, which lead to nontrivially nonlocal integrodifferential equations for the wave fields. Exact reciprocity relation is given as well as explicit analytic solutions for the transmission coefficients for both the high and low field side incidences. Numerical solutions are needed only for the high field side incident reflection coefficient. Numerical schemes are described and numerical results are presented together with a reliable error bound. Typically, energy absorption increases with poloidal field. The energy absorption increases with minority density at low values of minority density. However, it decreases at high minority density. Poloidal field effects weaken the dependence of energy absorption on the toroidal wave number. (c) 2000 American Institute of Physics
Speech-specificity of two audiovisual integration effects
DEFF Research Database (Denmark)
Eskelund, Kasper; Tuomainen, Jyrki; Andersen, Tobias
2010-01-01
Seeing the talker’s articulatory mouth movements can influence the auditory speech percept both in speech identification and detection tasks. Here we show that these audiovisual integration effects also occur for sine wave speech (SWS), which is an impoverished speech signal that naïve observers...... often fail to perceive as speech. While audiovisual integration in the identification task only occurred when observers were informed of the speech-like nature of SWS, integration occurred in the detection task both for informed and naïve observers. This shows that both speech-specific and general...... mechanisms underlie audiovisual integration of speech....
The giant-dipole-resonance effect in coulomb excitation of 10B
International Nuclear Information System (INIS)
Vermeer, W.J.; Zabel, T.H.; Esat, M.T.; Kuehner, J.A.; Spear, R.H.; Baxter, A.M.
1982-04-01
Coulomb excitation of the 0.718-MeV, Jsup(π) = 1 + , first excited state of 10 B has been studied using projectile excitation by 208 Pb and observing the backward scattered particles. The results give a clear indication of the virtual excitation of the giant dipole resonance as a second-order effect. The observed magnitude is consistent with the usual hydrodynamic model estimate and with a recent shell-model calculation
The effect of background absorption on the compound cross-section in resonance scattering
International Nuclear Information System (INIS)
Frenkel, A.
1976-01-01
The effect of channel-channel correlations in the compound cross-section is studied in a model of a resonance above a compound background characterized by equal absorption in all open channels. A general rule which cannot be derived from unitarity alone is proved for the fluctuating cross-section. It provides new understanding of level-level correlations in scattering through compound nucleus states. (author)
Lifetime-vibrational interference effects in resonantly excited x-ray emission spectra of CO
Energy Technology Data Exchange (ETDEWEB)
Skytt, P.; Glans, P.; Gunnelin, K. [Uppsala Univ. (Sweden)] [and others
1997-04-01
The parity selection rule for resonant X-ray emission as demonstrated for O{sub 2} and N{sub 2} can be seen as an effect of interference between coherently excited degenerate localized core states. One system where the core state degeneracy is not exact but somewhat lifted was previously studied at ALS, namely the resonant X-ray emission of amino-substituted benzene (aniline). It was shown that the X-ray fluorescence spectrum resulting from excitation of the C1s at the site of the {open_quotes}aminocarbon{close_quotes} could be described in a picture separating the excitation and the emission processes, whereas the spectrum corresponding to the quasi-degenerate carbons could not. Thus, in this case it was necessary to take interference effects between the quasi-degenerate intermediate core excited states into account in order to obtain agreement between calculations and experiment. The different vibrational levels of core excited states in molecules have energy splittings which are of the same order of magnitude as the natural lifetime broadening of core excitations in the soft X-ray range. Therefore, lifetime-vibrational interference effects are likely to appear and influence the band shapes in resonant X-ray emission spectra. Lifetime-vibrational interference has been studied in non-resonant X-ray emission, and in Auger spectra. In this report the authors discuss results of selectively excited soft X-ray fluorescence spectra of molecules, where they focus on lifetime-interference effects appearing in the band shapes.
Effects of error feedback on a nonlinear bistable system with stochastic resonance
International Nuclear Information System (INIS)
Li Jian-Long; Zhou Hui
2012-01-01
In this paper, we discuss the effects of error feedback on the output of a nonlinear bistable system with stochastic resonance. The bit error rate is employed to quantify the performance of the system. The theoretical analysis and the numerical simulation are presented. By investigating the performances of the nonlinear systems with different strengths of error feedback, we argue that the presented system may provide guidance for practical nonlinear signal processing
International Nuclear Information System (INIS)
Zhenping Li; Close, F.E.
1990-03-01
The photo and electroproduction of baryon resonances has been calculated using the Constituent Quark Model with chromodynamics consistent with O(υ 2 /c 2 ) for the quarks. We find that the successes of the nonrelativistic quark model are preserved, some problems are removed and that QCD mixing effects may become important with increasing q 2 in electroproduction. For the first time both spectroscopy and transitions receive a unified treatment with a single set of parameters. (author)
Experimental determination of resonance absorption cross sections for Zircaloy-2 and zirconium
Energy Technology Data Exchange (ETDEWEB)
Kocic, A; Markovic, V [Boris Kidric Institute of Nuclear Sciences, Vinca, Beograd (Yugoslavia)
1968-05-15
The integral absorption cross section for the neutron spectrum and the thermal absorption cross section for zircaloy-2 have been determined using the pile oscillator technique. Using both values and a measured ratio of the epithermal to the thermal flux, the effective resonance integrals were obtained. After subtraction of the contributions for alloy and impurity elements, the effective resonance integrals for zirconium were evaluated. An extrapolated value of 0.91{+-}0.10 was obtained for the dilute integral. (author)
The Effects of Integrating Laboratory Work with Theory on Academic ...
African Journals Online (AJOL)
The Effects of Integrating Laboratory Work with Theory on Academic Achievement in Secondary School Physics. ... Journal Home > Vol 4, No 4 (2010) > ... better than those taught by treating practical work after and separate from theory.
Sensing (un)binding events via surface plasmons: effects of resonator geometry
Antosiewicz, Tomasz J.; Claudio, Virginia; Käll, Mikael
2016-04-01
The resonance conditions of localized surface plasmon resonances (LSPRs) can be perturbed in any number ways making plasmon nanoresonators viable tools in detection of e.g. phase changes, pH, gasses, and single molecules. Precise measurement via LSPR of molecular concentrations hinge on the ability to confidently count the number of molecules attached to a metal resonator and ideally to track binding and unbinding events in real-time. These two requirements make it necessary to rigorously quantify relations between the number of bound molecules and response of plasmonic sensors. This endeavor is hindered on the one hand by a spatially varying response of a given plasmonic nanosensor. On the other hand movement of molecules is determined by stochastic effects (Brownian motion) as well as deterministic flow, if present, in microfluidic channels. The combination of molecular dynamics and the electromagnetic response of the LSPR yield an uncertainty which is little understood and whose effect is often disregarded in quantitative sensing experiments. Using a combination of electromagnetic finite-difference time-domain (FDTD) calculations of the plasmon resonance peak shift of various metal nanosensors (disk, cone, rod, dimer) and stochastic diffusion-reaction simulations of biomolecular interactions on a sensor surface we clarify the interplay between position dependent binding probability and inhomogeneous sensitivity distribution. We show, how the statistical characteristics of the total signal upon molecular binding are determined. The proposed methodology is, in general, applicable to any sensor and any transduction mechanism, although the specifics of implementation will vary depending on circumstances. In this work we focus on elucidating how the interplay between electromagnetic and stochastic effects impacts the feasibility of employing particular shapes of plasmonic sensors for real-time monitoring of individual binding reactions or sensing low concentrations
Effects of multi-photon interferences from internally generated fields in strongly resonant systems
International Nuclear Information System (INIS)
Deng, Lu; Payne, Marvin G.; Garrett, William R.
2006-01-01
In studies of various nonlinear optical phenomena, strong resonant features in the atomic or molecular response to multi-photon driven processes have been used to greatly enhance the visibility of otherwise weak higher-order processes. However, there are well defined circumstances where a multi-photon-resonant response of a target system leads to the generation of one or more new electromagnetic fields that can drastically change the overall system response from what would be expected from the imposed laser fields alone. New effects can occur and dominate some aspects of the nonlinear optical response because of the constructive or destructive interference between transition amplitudes along multiple excitation pathways between a given set of optically coupled states, where one of the pathways involve internally generated field(s). Under destructive interference some resonant enhancements can become completely canceled (suppressed). This review focuses on the class of optical interference effects associated with internally generated fields, that have been found to be capable of influencing a very significant number of basic physical phenomena in gas or vapor phase systems. It provides a historical overview of experimental and theoretical developments and a modern understanding of the underlying physics and its various manifestations that include: suppression of multi-photon excitation processes, suppression of stimulated emissions (Raman, hyper-Raman, and optically pumped stimulated emissions), saturation of parametric wave-mixing, pressure and beam-geometry dependent shifting of multi-photon-resonant absorption lines, and the suppression of Autler-Townes splitting and ac-stark shifts. Additionally, optical interference effects in some modern contexts, such as achieving multi-photon induced transparency, establishing single-photon self-interference based induced transparency, and generating entangled single photon states, are reviewed
International Nuclear Information System (INIS)
Huffman, P.R.; Roberson, N.R.; Gould, C.R.; Haase, D.G.
1993-01-01
In 1988, Bunakov proposed a test of parity (P) even time reversal (T) violation in the neighborhood of two interfering p-wave resonances of the same spin. A similar enhancement exists if a d-wave and s-wave resonance interfere. Until now, however, no suitable resonances have been located in nuclei which can be aligned, and the only tests of time reversal violation in neutron transmission have been carried out with MeV-energy neutrons. The authors estimate the deformation effect cross sections for neutron resonances in aligned 165 Ho, and estimate the sensitivity of a five-fold correlation time reversal test carried out on a resonance that exhibits a deformation effect
ν-barp for neutron-induced fission in resonance region: Spin and (n, γf) reaction effects
International Nuclear Information System (INIS)
Fort, E.; Long, P.; Frehaut, J.
1989-01-01
The average number of prompt neutrons ν-bar p emitted per fission event has been evaluated for 239 Pu with a special regard to the fluctuations experimentally observed in the low energy range. These fluctuations are demonstrated to have a significant impact for the applications especially the reactivity coefficient of advanced water reactors. Consequently, the ν-bar p curve has to be defined in the same fine energy mesh as the fission cross-section for accurate neutron source calculations. In this range formalisms are proposed to calculate ν-bar p from the resonance parameters, resolved or averaged. Using JEF1 library as a data base the analysis of several thermal, low moderated or fast systems shows a good convergence of the selected microscopic and integral informations. In the present evaluation the importance of the spin and (n, γf) effects in the generation of dips in the ν-bar p curve is emphasized. These effects which exist in the low energy range up to about 10 keV lead to a reduction of the effective value of ν-bar p . Predominant in the epithermal range, the spin effect progressively decreases and the reduction of ν-bar p is due to the (n, γf) effect only in the keV region. (author)
International Nuclear Information System (INIS)
Cheng, Haitao; Yang, Heng; Li, XinXin; Wang, Yuelin
2013-01-01
A novel piezoresistive sensing method is presented herein for the detection of nanobeam resonator based on a monolithically integrated MOS (metal–oxide–semiconductor) capacitor structure. The bottom layer of the nanobeam located beneath the MOS capacitor is utilized as a piezoresistor for the detection of internal stress resulting from nanobeam deformation, and therefore the challenging process of ultra-shallow junction doping is avoided. When a bias voltage applied on the MOS gate exceeds the threshold, the depletion layer width is built up to the maximum, and the piezoresistive cancellation effect beside the neutral plane is eliminated. Based on a conventional microelectromechanical (MEMS) process, an MOS capacitor is fabricated at the terminal of a double-clamped nanobeam with dimensions of 46 µm × 7 µm × 149 nm. The measured R–V curve of this MOS structure presents a 64.7 nm thick piezoresistor which closely agrees with the design. This double-clamped nanobeam is excited into mechanical resonance by mounting it on a piezoelectric ceramic, and the amplitude–frequency response is measured by a network analyzer. The measured resonant frequency is 3.97 MHz and the quality (Q)-factor is 82 in atmosphere environment. Besides, this piezoresistive sensing method is verified by a laser-Doppler vibrometry. (paper)
Salleh, Tuan Salwani; Zakaria, Effandi
2016-01-01
The objective of this research is to investigate the effectiveness of a learning strategy using Maple in integral calculus. This research was conducted using a quasi-experimental nonequivalent control group design. One hundred engineering technology students at a technical university were chosen at random. The effectiveness of the learning…
In vitro evaluation of genotoxic effects under magnetic resonant coupling wireless power transfer.
Mizuno, Kohei; Shinohara, Naoki; Miyakoshi, Junji
2015-04-07
Wireless power transfer (WPT) technology using the resonant coupling phenomenon has been widely studied, but there are very few studies concerning the possible relationship between WPT exposure and human health. In this study, we investigated whether exposure to magnetic resonant coupling WPT has genotoxic effects on WI38VA13 subcloned 2RA human fibroblast cells. WPT exposure was performed using a helical coil-based exposure system designed to transfer power with 85.4% efficiency at a 12.5-MHz resonant frequency. The magnetic field at the positions of the cell culture dishes is approximately twice the reference level for occupational exposure as stated in the International Commission on Non-Ionizing Radiation Protection (ICNIRP) guidelines. The specific absorption rate at the positions of the cell culture dishes matches the respective reference levels stated in the ICNIRP guidelines. For assessment of genotoxicity, we studied cell growth, cell cycle distribution, DNA strand breaks using the comet assay, micronucleus formation, and hypoxanthine-guanine phosphoribosyltransferase (HPRT) gene mutation, and did not detect any significant effects between the WPT-exposed cells and control cells. Our results suggest that WPT exposure under the conditions of the ICNIRP guidelines does not cause detectable cellular genotoxicity.
In Vitro Evaluation of Genotoxic Effects under Magnetic Resonant Coupling Wireless Power Transfer
Directory of Open Access Journals (Sweden)
Kohei Mizuno
2015-04-01
Full Text Available Wireless power transfer (WPT technology using the resonant coupling phenomenon has been widely studied, but there are very few studies concerning the possible relationship between WPT exposure and human health. In this study, we investigated whether exposure to magnetic resonant coupling WPT has genotoxic effects on WI38VA13 subcloned 2RA human fibroblast cells. WPT exposure was performed using a helical coil-based exposure system designed to transfer power with 85.4% efficiency at a 12.5-MHz resonant frequency. The magnetic field at the positions of the cell culture dishes is approximately twice the reference level for occupational exposure as stated in the International Commission on Non-Ionizing Radiation Protection (ICNIRP guidelines. The specific absorption rate at the positions of the cell culture dishes matches the respective reference levels stated in the ICNIRP guidelines. For assessment of genotoxicity, we studied cell growth, cell cycle distribution, DNA strand breaks using the comet assay, micronucleus formation, and hypoxanthine-guanine phosphoribosyltransferase (HPRT gene mutation, and did not detect any significant effects between the WPT-exposed cells and control cells. Our results suggest that WPT exposure under the conditions of the ICNIRP guidelines does not cause detectable cellular genotoxicity.
Magnetic resonance thermometry for monitoring photothermal effects of interstitial laser irradiation
Goddard, Jessica; Jose, Jessnie; Figueroa, Daniel; Le, Kelvin; Liu, Hong; Nordquist, Robert E.; Hode, Tomas; Chen, Wei R.
2012-03-01
Selective photothermal interaction using dye-assisted non-invasive laser irradiation has limitations when treating deeper tumors or when the overlying skin is heavily pigmented. We developed an interstitial laser irradiation method to induce the desired photothermal effects. An 805-nm near-infrared laser with a cylindrical diffuser was used to treat rat mammary tumors by placing the active tip of the fiber inside the target tumors. Three different power settings (1.0 to 1.5 watts) were applied to treat animal tumors with an irradiation duration of 10 minutes. The temperature distributions of the treated tumors were measured by a 7.1-Tesla magnetic resonance imager using proton resonance frequency (PRF) method. Three-dimensional temperature profiles were reconstructed and assessed using PRF. This is the first time a 7.1-Tesla magnetic resonance imager has been used to monitor interstitial laser irradiation via PRF. This study provides a basic understanding of the photothermal interaction needed to control the thermal damage inside tumor using interstitial laser irradiation. It also shows that PRF can be used effectively in monitoring photothermal interaction. Our long-term goal is to develop a PRF-guided laser therapy for cancer treatment.
International Nuclear Information System (INIS)
Prabhu Gaunkar, N.; Bouda, N. R. Y.; Nlebedim, I. C.; Hadimani, R. L.; Mina, M.; Jiles, D. C.; Bulu, I.; Ganesan, K.; Song, Y. Q.
2015-01-01
This work presents investigations and detailed analysis of ringing in a non-resonant pulsed nuclear magnetic resonance (NMR) circuit. Ringing is a commonly observed phenomenon in high power switching circuits. The oscillations described as ringing impede measurements in pulsed NMR systems. It is therefore desirable that those oscillations decay fast. It is often assumed that one of the causes behind ringing is the role of the magnetic core used in the antenna (acting as an inductive load). We will demonstrate that an LRC subcircuit is also set-up due to the inductive load and needs to be considered due to its parasitic effects. It is observed that the parasitics associated with the inductive load become important at certain frequencies. The output response can be related to the response of an under-damped circuit and to the magnetic core material. This research work demonstrates and discusses ways of controlling ringing by considering interrelationships between different contributing factors
Effect of surface roughness on substrate-tuned gold nanoparticle gap plasmon resonances.
Lumdee, Chatdanai; Yun, Binfeng; Kik, Pieter G
2015-03-07
The effect of nanoscale surface roughness on the gap plasmon resonance of gold nanoparticles on thermally evaporated gold films is investigated experimentally and numerically. Single-particle scattering spectra obtained from 80 nm diameter gold particles on a gold film show significant particle-to-particle variation of the peak scattering wavelength of ±28 nm. The experimental results are compared with numerical simulations of gold nanoparticles positioned on representative rough gold surfaces, modeled based on atomic force microscopy measurements. The predicted spectral variation and average resonance wavelength show good agreement with the measured data. The study shows that nanometer scale surface roughness can significantly affect the performance of gap plasmon-based devices.
Energy Technology Data Exchange (ETDEWEB)
Prabhu Gaunkar, N., E-mail: neelampg@iastate.edu; Bouda, N. R. Y.; Nlebedim, I. C.; Hadimani, R. L.; Mina, M.; Jiles, D. C. [Department of Electrical and Computer Engineering, Iowa State University, Ames, Iowa 50011 (United States); Bulu, I.; Ganesan, K.; Song, Y. Q. [Schlumberger-Doll Research, Cambridge, Massachusetts 02139 (United States)
2015-05-07
This work presents investigations and detailed analysis of ringing in a non-resonant pulsed nuclear magnetic resonance (NMR) circuit. Ringing is a commonly observed phenomenon in high power switching circuits. The oscillations described as ringing impede measurements in pulsed NMR systems. It is therefore desirable that those oscillations decay fast. It is often assumed that one of the causes behind ringing is the role of the magnetic core used in the antenna (acting as an inductive load). We will demonstrate that an LRC subcircuit is also set-up due to the inductive load and needs to be considered due to its parasitic effects. It is observed that the parasitics associated with the inductive load become important at certain frequencies. The output response can be related to the response of an under-damped circuit and to the magnetic core material. This research work demonstrates and discusses ways of controlling ringing by considering interrelationships between different contributing factors.
Effect of annealing induced residual stress on the resonance frequency of SiO2 microcantilevers
Balasubramanian, S.; Prabakar, K.; Tripura Sundari, S.
2018-04-01
In the present work, effect of residual stress, induced due to annealing of SiO2 microcantilevers (MCs) on their resonance frequency is studied. SiO2MCs of various dimensions were fabricated using direct laser writer & wet chemical etching method and were annealed at 800 °C in oxygen environment, post release. The residual stress was estimated from the deflection profile of the MCs measured using 3D optical microscope, before and after annealing. Resonance frequency of the MCs was measured using nano-vibration analyzer and was found to change after annealing. Further the frequency shift was found to depend on the MC dimensions. This is attributed to the large stress gradients induced by annealing and associated stiffness changes.
Spaceflight Effect on White Matter Structural Integrity
Lee, Jessica K.; Kopplemans, Vincent; Paternack, Ofer; Bloomberg, Jacob J.; Mulavara, Ajitkumar P.; Seidler, Rachael D.
2017-01-01
Recent reports of elevated brain white matter hyperintensity (WMH) counts and volume in postflight astronaut MRIs suggest that further examination of spaceflight's impact on the microstructure of brain white matter is warranted. To this end, retrospective longitudinal diffusion-weighted MRI scans obtained from 15 astronauts were evaluated. In light of the recent reports of microgravity-induced cephalad fluid shift and gray matter atrophy seen in astronauts, we applied a technique to estimate diffusion tensor imaging (DTI) metrics corrected for free water contamination. This approach enabled the analysis of white matter tissue-specific alterations that are unrelated to fluid shifts, occurring from before spaceflight to after landing. After spaceflight, decreased fractional anisotropy (FA) values were detected in an area encompassing the superior and inferior longitudinal fasciculi and the inferior fronto-occipital fasciculus. Increased radial diffusivity (RD) and decreased axial diffusivity (AD) were also detected within overlapping regions. In addition, FA values in the corticospinal tract decreased and RD measures in the precentral gyrus white matter increased from before to after flight. The results show disrupted structural connectivity of white matter in tracts involved in visuospatial processing, vestibular function, and movement control as a result of spaceflight. The findings may help us understand the structural underpinnings of the extensive spaceflight-induced sensorimotor remodeling. Prospective longitudinal assessment of the white matter integrity in astronauts is needed to characterize the evolution of white matter microstructural changes associated with spaceflight, their behavioral consequences, and the time course of recovery. Supported by a grant from the National Space Biomedical Research Institute, NASA NCC 9-58.
Autler-Townes effect in a strongly driven electromagnetically induced transparency resonance
International Nuclear Information System (INIS)
Yang Lijun; Zhang Lianshui; Li Xiaoli; Han Li; Fu Guangsheng; Manson, Neil B.; Suter, Dieter; Wei Changjiang
2005-01-01
In this paper we study the nonlinear behavior of an electromagnetically induced transparency (EIT) resonance subject to a coherent driving field. The EIT is associated with a Λ three-level system where two hyperfine levels within an electronic ground state are coupled to a common excited state level by a coupling field and a probe field. In addition there is an radio-frequency (rf) field driving a hyperfine transition within the ground state. The paper contrasts two different situations. In one case the rf-driven transition shares a common level with the probed transition and in the second case it shares a common level with the coupled transition. In both cases the EIT resonance is split into a doublet and the characteristics of the EIT doublet are determined by the strength and frequency of the rf-driving field. The doublet splitting originates from the rf-field induced dynamic Stark effect and has close analogy with the Autler-Townes effect observed in three-level pump-probe spectroscopy study. The situation changes when the rf field is strong and the two cases are very different. One is analogous to two Λ three-level systems with EIT resonance associated with each. The other corresponds to a doubly driven three-level system with rf-field-induced electromagnetically induced absorption resonance. The two situations are modeled using numerical solutions of the relevant equation of motion of density matrix. In addition a physical account of their behaviors is given in terms of a dressed state picture
The Dilution Effect and Information Integration in Perceptual Decision Making.
Directory of Open Access Journals (Sweden)
Jared M Hotaling
Full Text Available In cognitive science there is a seeming paradox: On the one hand, studies of human judgment and decision making have repeatedly shown that people systematically violate optimal behavior when integrating information from multiple sources. On the other hand, optimal models, often Bayesian, have been successful at accounting for information integration in fields such as categorization, memory, and perception. This apparent conflict could be due, in part, to different materials and designs that lead to differences in the nature of processing. Stimuli that require controlled integration of information, such as the quantitative or linguistic information (commonly found in judgment studies, may lead to suboptimal performance. In contrast, perceptual stimuli may lend themselves to automatic processing, resulting in integration that is closer to optimal. We tested this hypothesis with an experiment in which participants categorized faces based on resemblance to a family patriarch. The amount of evidence contained in the top and bottom halves of each test face was independently manipulated. These data allow us to investigate a canonical example of sub-optimal information integration from the judgment and decision making literature, the dilution effect. Splitting the top and bottom halves of a face, a manipulation meant to encourage controlled integration of information, produced farther from optimal behavior and larger dilution effects. The Multi-component Information Accumulation model, a hybrid optimal/averaging model of information integration, successfully accounts for key accuracy, response time, and dilution effects.
The Dilution Effect and Information Integration in Perceptual Decision Making.
Hotaling, Jared M; Cohen, Andrew L; Shiffrin, Richard M; Busemeyer, Jerome R
2015-01-01
In cognitive science there is a seeming paradox: On the one hand, studies of human judgment and decision making have repeatedly shown that people systematically violate optimal behavior when integrating information from multiple sources. On the other hand, optimal models, often Bayesian, have been successful at accounting for information integration in fields such as categorization, memory, and perception. This apparent conflict could be due, in part, to different materials and designs that lead to differences in the nature of processing. Stimuli that require controlled integration of information, such as the quantitative or linguistic information (commonly found in judgment studies), may lead to suboptimal performance. In contrast, perceptual stimuli may lend themselves to automatic processing, resulting in integration that is closer to optimal. We tested this hypothesis with an experiment in which participants categorized faces based on resemblance to a family patriarch. The amount of evidence contained in the top and bottom halves of each test face was independently manipulated. These data allow us to investigate a canonical example of sub-optimal information integration from the judgment and decision making literature, the dilution effect. Splitting the top and bottom halves of a face, a manipulation meant to encourage controlled integration of information, produced farther from optimal behavior and larger dilution effects. The Multi-component Information Accumulation model, a hybrid optimal/averaging model of information integration, successfully accounts for key accuracy, response time, and dilution effects.
Energy Technology Data Exchange (ETDEWEB)
Mayer, Michael
2015-03-09
The scope of the thesis is the development of a method for improvement of efficient integrated management systems for high reliability organizations (HRO). A comprehensive analysis of severe accident prevention is performed. Severe accident management, mitigation measures and business continuity management are not included. High reliability organizations are complex and potentially dynamic organization forms that can be inherently dangerous like nuclear power plants, offshore platforms, chemical facilities, large ships or large aircrafts. A recursive generic management system model (RGM) was development based on the following factors: systemic and cybernetic Asepcts; integration of different management fields, high decision quality, integration of efficient methods of safety and risk analysis, integration of human reliability aspects, effectiveness evaluation and improvement.
Integrating technologies for effective knowledge management
Energy Technology Data Exchange (ETDEWEB)
Beaugrand, F.S.; Curtis, T.A. [Public Petroleum Data Model, PPDM Association, Calgary, AB (Canada)
2002-06-01
In order to succeed in today's business environment, effective knowledge management strategies are needed along with effective tools to solve real business problems. Relational databases provide accessible and practical tools that can be used to manage corporate knowledge assets. However, technology is growing so rapidly that it is difficult and too expensive for individual corporations to pursue each line of development independently. Collaborative efforts are needed to improve access to shared knowledge. The PPDM Association is an international not for profit standards body that is working collaboratively with the petroleum exploration and production industry to develop standards for managing data and knowledge, spatially enabling data, standardizing data content and data exchange. The PPDM Association provides a vendor-neutral environment for development, technical support and a methodology for designing, developing and publishing technical deliverables.
Radiation effects on the integrity of paper
International Nuclear Information System (INIS)
Otero D'Almeida, Maria Luiza; Medeiros Barbosa, Patricia de Souza; Boaratti, Marcelo Fernando Guerra; Borrely, Sueli Ivone
2009-01-01
Books and documents attacked by fungi and insects have already been treated by radiation for disinfestations purposes. However, there is still need to investigate the influence of radiation on the cellulose paper structure. The aim of this research was to study the effects of radiation on paper properties, especially those related to strength and appearance. Paper sheets for this study were prepared in the laboratory, using bleached eucalyptus pulp as raw material. No additives were used to concentrate the attention only on the effects of irradiation on the pure cellulose matrix. The samples were irradiated at IPEN's 60 Co Gammacell irradiator with six radiation doses, from 3 to 15 kGy at the dose rate 0.817 Gy/s. The properties of paper sheets were tested after irradiation and compared with unirradiated samples according to ISO methods. No significant changes were detected in paper samples irradiated up to 15 kGy.
Quantum size effects on spin-tunneling time in a magnetic resonant tunneling diode
Saffarzadeh, Alireza; Daqiq, Reza
2009-01-01
We study theoretically the quantum size effects of a magnetic resonant tunneling diode (RTD) with a (Zn,Mn)Se dilute magnetic semiconductor layer on the spin-tunneling time and the spin polarization of the electrons. The results show that the spin-tunneling times may oscillate and a great difference between the tunneling time of the electrons with opposite spin directions can be obtained depending on the system parameters. We also study the effect of structural asymmetry which is related to t...
Integration of effects on human populations
International Nuclear Information System (INIS)
Harwell, M.A.; Harwell, C.C.
1985-01-01
It seems possible that several hundred millions of humans could die from the direct effects of nuclear war. The indirect effects could result in the loss of one to several billions of humans. How close the latter projection would come to loss of all humans is problematical, but the current best estimation is that this result would not follow from the physical and societal perturbations currently projected to occur after a large-scale nuclear war. One important issue of scale to keep in mind is the difference between estimating that on a global scale the bases for human support would be undetermined for a particular fraction of the population (e.g., estimating insufficient food to support more than a certain fraction of the current population), and predicting the survival strategies of small groups of people. Projections of global-scale population losses do not mean that even in those areas in which humans would be expected to die, all would suffer the same fate. No analysis have been attempted here concerning the capability of selected humans on a relatively small scale (e.g., individual, family, community level) to find a successful strategy for survival. That a person or group in a combatant country might find a way to escape the effects of radiation, societal disruptions, climatic alterations, and the host of other potential disruptions, and still continue to survive seems possible, even in devastated areas. That billions of people could do so in the absence of a sufficient food support base is impossible. Thus, one needs to distinguish carefully between possible survival strategies on a small scale, and the physical limitations of support for massive numbers of people on a large scale
Zhuang, L.; Roeloffzen, C.G.H.; Meijerink, Arjan; Burla, M.; Marpaung, D.A.I.; Leinse, Arne; Hoekman, M.; Heideman, Rene; van Etten, Wim
2010-01-01
An experimental prototype is presented that illustrates the implementation aspects and feasibility of the novel ring resonator-based optical beamformer concept that has been developed and analyzed in Part I of this paper . This concept can be used for seamless control of the reception angle in
Meijerink, Arjan; Roeloffzen, C.G.H.; Meijerink, Roland; Zhuang, L.; Marpaung, D.A.I.; Bentum, Marinus Jan; Burla, M.; Verpoorte, Jaco; Jorna, Pieter; Huizinga, Adriaan; van Etten, Wim
2010-01-01
A novel optical beamformer concept is introduced that can be used for seamless control of the reception angle in broadband wireless receivers employing a large phased array antenna (PAA). The core of this beamformer is an optical beamforming network (OBFN), using ring resonator-based broadband
The influence of temperature in the characterization of nuclear resonance
International Nuclear Information System (INIS)
Campos, T.P.R. de; Martinez, A.S.
1986-01-01
A detailed analysis carried out to determine the temperature effects on the selection of different types of resonance for Resonance Integral calculations is presented. The type of approximation (WR, IR or NR) to be applied to the slowing down integral of the neutron balance equation depends on the relationship between the average energy lost by the neutron and the practical width. A method to include the temperature dependence in the ratio ΔE/GAMMA sub(p) is proposed. The results allowed us to show that this dependence negligence may lead to large errors in the Resonance Integral calculation. (Author) [pt
International Nuclear Information System (INIS)
Barroso, D.E.G.
1982-01-01
A sensitivity analysis of reactor integral parameter to more 10% variation in the resolved resonance parameters #betta##betta# of the fertile isotope and the variations of more 10% in the α values (#betta# sub(#betta#)/#betta# sub(f)) of fissile isotopes of PWR fuel elements, is done. The analysis is made with thermal and epithermal spectra, those last generated in a fuel cell with low V sub(M)/V sub(F). The HAMMER system, the interface programs HELP and LITHE and the HAMMER computer codes, were used as a base for this study. (E.G.) [pt
An integral effect test facility of the SMART, SMART ITL
Energy Technology Data Exchange (ETDEWEB)
Park, Hyun Sik; Moon, Sang Ki; Kim, Yeon Sik; Cho, Seok; Choi, Ki Yong; Bae, Hwang; Kim, Dong Eok; Choi, Nam Hyun; Min, Kyoung Ho; Ko, Yung Joo; Shin, Yong Cheol; Park, Rae Joon; Lee, Won Jae; Song, Chul Hwa; Yi, Sung Jae [KAERI, Daejeon (Korea, Republic of)
2012-10-15
SMART (System integrated Modular Advanced ReacTor) is a 330 MWth integral pressurized water reactor (iPWR) developed by KAERI and had obtained standard design approval (SDA) from Korean regulatory authority on July 2012. In this SMART design main components including a pressurizer, reactor coolant pumps and steam generators are installed in a reactor pressure vessel without any large connecting pipes. As the LBLOCA scenario is inherently excluded, its safety systems could be simplified only to ensure the safety during the SBLOCA scenarios and the other system transients. An integral effect test loop for the SMART (SMART ITL), or called as FESTA, had been designed to simulate the integral thermal hydraulic behavior of the SMART. The objectives of the SMART ITL are to investigate and understand the integral performance of reactor systems and components and the thermal hydraulic phenomena occurred in the system during normal, abnormal and emergency conditions, and to verify the system safety during various design basis events of the SMART. The integral effect test data will also be used to validate the related thermal hydraulic models of the safety analysis code such as TASS/SMR S, which is used for performance and accident analysis of the SMART design. This paper introduces the scaling analysis and scientific design of the integral test facility of the SMART, SMART ITL and its scaling analysis results.
Continuous neutron slowing down theory applied to resonances
International Nuclear Information System (INIS)
Segev, M.
1977-01-01
Neutronic formalisms that discretize the neutron slowing down equations in large numerical intervals currently account for the bulk effect of resonances in a given interval by the narrow resonance approximation (NRA). The NRA reduces the original problem to an efficient numerical formalism through two assumptions: resonance narrowness with respect to the scattering bands in the slowing down equations and resonance narrowness with respect to the numerical intervals. Resonances at low energies are narrow neither with respect to the slowing down ranges nor with respect to the numerical intervals, which are usually of a fixed lethargy width. Thus, there are resonances to which the NRA is not applicable. To stay away from the NRA, the continuous slowing down (CSD) theory of Stacey was invoked. The theory is based on a linear expansion in lethargy of the collision density in integrals of the slowing down equations and had notable success in various problems. Applying CSD theory to the assessment of bulk resonance effects raises the problem of obtaining efficient quadratures for integrals involved in the definition of the so-called ''moderating parameter.'' The problem was solved by two approximations: (a) the integrals were simplified through a rationale, such that the correct integrals were reproduced for very narrow or very wide resonances, and (b) the temperature-broadened resonant line shapes were replaced by nonbroadened line shapes to enable analytical integration. The replacement was made in such a way that the integrated capture and scattering probabilities in each resonance were preserved. The resulting formalism is more accurate than the narrow-resonance formalisms and is equally as efficient
Thermal Hydraulic Integral Effect Tests for Pressurized Water Reactors
Energy Technology Data Exchange (ETDEWEB)
Baek, W. P.; Song, C. H.; Kim, Y. S. and others
2005-02-15
The objectives of the project are to construct a thermal-hydraulic integral effect test facility and to perform various integral effect tests for design, operation, and safety regulation of pressurized water reactors. During the first phase of this project (1997.8{approx}2002.3), the basic technology for thermal-hydraulic integral effect tests was established and the basic design of the test facility was accomplished: a full-height, 1/300-volume-scaled full pressure facility for APR1400, an evolutionary pressurized water reactor that was developed by Korean industry. Main objectives of the present phase (2002.4{approx}2005.2), was to optimize the facility design and to construct the experimental facility. We have performed following researches: 1) Optimization of the basic design of the thermal-hydraulic integral effect test facility for PWRs - ATLAS (Advanced Thermal-hydraulic Test Loop for Accident Simulation) - Reduced height design for APR1400 (+ specific design features of KSNP safety injection systems) - Thermal-hydraulic scaling based on three-level scaling methodology by Ishii et al. 2) Construction of the ATLAS facility - Detailed design of the test facility - Manufacturing and procurement of components - Installation of the facility 3) Development of supporting technology for integral effect tests - Development and application of advanced instrumentation technology - Preliminary analysis of test scenarios - Development of experimental procedures - Establishment and implementation of QA system/procedure.
Effects of the radial electric field resonances on the particle orbits and loss cones in TJ-II
International Nuclear Information System (INIS)
Guasp, J.; Liniers, M.
1997-07-01
The effects of the radial electric field resonances on the trapping and confinement of low and intermediate energy ions (0.1-1 keV) for the Reference configuration of TJ-II have been analysed. In TJ-II these resonances appear for electric potentials that grow with pitch and with the square root of the initial kinetic energy and are placed inside strips whose width increases with the initial radius and with the absolute value of initial pitch. The 0-Resonance is the most important one for particle trapping, it appears for high electric potential (between 1000 and 3000 V for 0.5 keV ions) with the same sign than pitch, inside very wide strips (several thousands of V). Along these band periphery, for potential intensities below the central resonant values, there exists a very strong increase of particle trapping. Instead, around the resonance center, the trapping is inhibited and a very strong increase of the passing particle population appears. This increase is higher for the torus external side (Theta approximately 0 degree centigree) and for small initial radius. For peripherical particles wide loss strips appear along the border of the resonant band corresponding to more positive potential. The 2-Resonance has small effect on trapping but affects strongly to the of peripherical passing particles. It appears for moderate electric potential (between 400 and 1000 V for 0.5 keV ions) with sign opposite than pitch and inside narrow bands than the 0-Resonance. In this case a loss of peripherical passing particles appears, placed also along the more positive potential band side. The other Resonances (except the -4) have much less effect on particle trapping and confinement. All these phenomena have been explained by the action of magnetic barriers and different mechanisms for particle orbit modification. (Author) 8 refs
Nguyen, Van Do; Pham, Duc Khue; Kim, Tien Thanh; Kim, Guinyun; Lee, Manwoo; Kim, Kyung Sook; Kang, Heung-Sik; Cho, Moo-Hyun; Ko, In Soo; Namkung, Won
2011-01-01
The thermal neutron cross-section and the resonance integral of the 165Ho(n,γ) 166gHo reaction have been measured by the activation method using a 197Au(n,γ) 198Au monitor reaction as a single comparator. The high-purity natural Ho and Au foils with and without a cadmium shield case of 0.5 mm thickness were irradiated in a neutron field of the Pohang neutron facility. The induced activities in the activated foils were measured with a calibrated p-type high-purity Ge detector. The correction factors for the γ-ray attenuation ( Fg), the thermal neutron self-shielding ( Gth), the resonance neutron self-shielding ( Gepi) effects, and the epithermal neutron spectrum shape factor ( α) were taken into account. The thermal neutron cross-section for the 165Ho(n,γ) 166gHo reaction has been determined to be 59.7 ± 2.5 barn, relative to the reference value of 98.65 ± 0.09 barn for the 197Au(n,γ) 198Au reaction. By assuming the cadmium cut-off energy of 0.55 eV, the resonance integral for the 165Ho(n,γ) 166gHo reaction is 671 ± 47 barn, which is determined relative to the reference value of 1550 ± 28 barn for the 197Au(n,γ) 198Au reaction. The present results are, in general, good agreement with most of the previously reported data within uncertainty limits.
Effect of spatially correlated noise on coherence resonance in a network of excitable cells
International Nuclear Information System (INIS)
Kwon, Okyu; Jo, Hang-Hyun; Moon, Hie-Tae
2005-01-01
We study the effect of spatially correlated noise on coherence resonance (CR) in a Watts-Strogatz small-world network of Fitz Hugh-Nagumo neurons, where the noise correlation decays exponentially with distance between neurons. It is found that CR is considerably improved just by a small fraction of long-range connections for an intermediate coupling strength. For other coupling strengths, an abrupt change in CR occurs following the drastic fracture of the clustered structures in the network. Our study shows that spatially correlated noise plays a significant role in the phenomenon of CR reinforcing the role of the clustered structure of the system
Energy Technology Data Exchange (ETDEWEB)
Ziener, Christian Herbert
2008-07-01
The properties of dephasing and the resulting relaxation of the magnetization are the basic principle on which all magnetic resonance imaging methods are based. The signal obtained from the gyrating spins is essentially determined by the properties of the considered tissue. Especially the susceptibility differences caused by magnetized materials (for example, deoxygenated blood, BOLD-effect) or magnetic nanoparticles are becoming more important for biomedical imaging. In the present work, the influence of such field inhomogeneities on the NMR-signal is analyzed. (orig.)
Postmortem magnetic resonance images of the injured brain: effective evidence in the courtroom.
Harris, L S
1991-09-01
Magnetic resonance images (MRI) of the whole, formalin-fixed brain produce details of pathologic changes deep within brain substance not apparent on external examination. Photographs of these radiographic images present pathologic features in a black-and-white, 2-dimensional format which has proven particularly effective in court before judge and jury. This pathologist has noted acceptance of such photographs in explaining to jurors the details of his testimony in selected cases where brain trauma resulted in a wrongful death. Penetrating missile wounds and blunt impact injuries are particularly well documented by this method.
Orbital alignment effects in near-resonant Rydberg atoms-rare gas collisions
International Nuclear Information System (INIS)
Isaacs, W.A.; Morrison, M.A.
1993-01-01
Recent experimental and theoretical studies of near-resonant energy transfer collisions involving rare-gas atoms and alkali or alkaline earth atoms which have been initially excited to an aligned state via one or more linearly polarized rasters have yielded a wealth of insight into orbital alignment and related effects. We have extended this inquiry to initially aligned Rydberg states, examining state-to-state and alignment-selected cross sections using quantum collision theory augmented by approximations appropriate to the special characteristics of the Rydberg state (e.g., the quasi-free-electron model and the impulse approximation)
International Nuclear Information System (INIS)
Pakter, R.; Schneider, R.S.; Rizzato, F.B.
1993-01-01
The cyclotron-resonance laser accelerator (CRLA), where a coherent electromagnetic wave may transfer a large amount of energy to a beam of electrons gravitating in a guide magnetic field is studied. This large amount of transferred energy takes place due to the autoresonance mechanism where, under some ideal conditions, an initial wave-particle synchronism is self-sustained throughout the accelerating period. An improved analysis of the mentioned self-consistent wave-particle interaction, taking into account a possible frequency mismatch between wave and particles. It is also shown how the frequency mismatch can compensate the dispersion effects. (L.C.J.A.)
Limiting effects on laser compression by resonant backward Raman scattering in modern experiments
International Nuclear Information System (INIS)
Yampolsky, Nikolai A.; Fisch, Nathaniel J.
2011-01-01
Through resonant backward Raman scattering, the plasma wave mediates the energy transfer between long pump and short seed laser pulses. These mediations can result in pulse compression at extraordinarily high powers. However, both the overall efficiency of the energy transfer and the duration of the amplified pulse depend upon the persistence of the plasma wave excitation. At least with respect to the recent state-of-the-art experiments, it is possible to deduce that at present the experimentally realized efficiency of the amplifier is likely constrained mainly by two effects, namely, the pump chirp and the plasma wave wavebreaking.
One phonon resonant Raman scattering in semiconductor quantum wires: Magnetic field effect
Energy Technology Data Exchange (ETDEWEB)
Betancourt-Riera, Re., E-mail: rbriera@posgrado.cifus.uson.mx [Instituto Tecnologico de Hermosillo, Avenida Tecnologico S/N, Colonia Sahuaro, C.P. 83170, Hermosillo, Sonor, (Mexico); Departamento de Investigacion en Fisica, Universidad de Sonora, Apartado Postal 5-088, C.P. 83190, Hermosillo, Sonora (Mexico); Betancourt-Riera, Ri. [Instituto Tecnologico de Hermosillo, Avenida Tecnologico S/N, Colonia Sahuaro, C.P. 83170, Hermosillo, Sonora (Mexico); Nieto Jalil, J.M. [Tecnologico de Monterrey-Campus Sonora Norte, Bulevar Enrique Mazon Lopez No. 965, C.P. 83000, Hermosillo, Sonora (Mexico); Riera, R. [Departamento de Investigacion en Fisica, Universidad de Sonora, Apartado Postal 5-088, C.P. 83190, Hermosillo, Sonora (Mexico)
2013-02-01
We have developed a theory of one phonon resonant Raman scattering in a semiconductor quantum wire of cylindrical geometry in the presence of an external magnetic field distribution, parallel to the cylinder axis. The effect of the magnetic field in the electron and hole states, and in the Raman scattering efficiency, is determinate. We consider the electron-phonon interaction using a Froehlich-type Hamiltonian, deduced for the case of complete confinement phonon modes by Comas and his collaborators. We also assume T=0 K, a single parabolic conduction and valence bands. The spectra are discussed for different magnetic field values and the selection rules for the processes are also studied.
Calculating many-body effects in resonant [(dtμ)d2e] formation
International Nuclear Information System (INIS)
Leon, M.
1986-01-01
A method is developed for calculating the effect of neighboring molecules on the resonant molecular formation reaction tμ + D 2 → [(dtμ)d2e]*, avoiding any expansion in powers of the density. Using a simplified model, the role of collisional broadening, motional narrowing, and the interference of different formation amplitudes is examined. This model is used to generate molecular formation rates as functions of density for fixed temperature. The generalization which will allow comparison with experimental data is discussed
Effects of Resonant Helical Field on Toroidal Field Ripple in IR-T1 Tokamak
Mahdavipour, B.; Salar Elahi, A.; Ghoranneviss, M.
2018-02-01
The toroidal magnetic field which is created by toroidal coils has the ripple in torus space. This magnetic field ripple has an importance in plasma equilibrium and stability studies in tokamak. In this paper, we present the investigation of the interaction between the toroidal magnetic field ripple and resonant helical field (RHF). We have estimated the amplitude of toroidal field ripples without and with RHF (with different q = m/n) ( m = 2, m = 3, m = 4, m = 5, m = 2 & 3, n = 1) using “Comsol Multiphysics” software. The simulations show that RHF has effects on the toroidal ripples.
Hien, Nguyen Thi; Kim, Guinyun; Kim, Kwangsoo; Do, Nguyen Van; Khue, Pham Duc; Thanh, Kim Tien; Shin, Sung-Gyun; Cho, Moo-Hyun
2018-06-01
The thermal neutron capture cross-section (σ0) and resonance integral (I0) of the 108Pd(n,γ)109Pd reaction have been measured relative to that of the monitor reaction 197Au(n,γ)198Au. The measurements were carried out using the neutron activation with the cadmium ratio method. Both the samples and monitors were irradiated with and without cadmium cover of 0.5 mm thickness. The induced activities of the reaction products were measured with a well calibrated HPGe γ-ray detector. In order to improve the accuracy of the results, the necessary corrections for the counting losses were made. The thermal neutron capture cross-section and resonance integral of the 108Pd(n,γ)109Pd reaction were determined to be σ0,Pd = 8.68 ± 0.41 barn and I0,Pd = 245.6 ± 24.8 barn, respectively. The obtained results are compared with literature values and discussed.
On the logistics effects of integrated product and package design
DEFF Research Database (Denmark)
Bramklev, Caroline; Hansen, Claus Thorp
2007-01-01
obtaining error-free deliveries, saving costs and avoiding quality problems. Thus, the authors of this paper see a challenge in developing the theory and methodology for Integrated Product and Package Design. In this paper we take a first step in this direction. Firstly, we have carried out a broad review...... of literature, which shows that there is a need for research into Integrated Product and Package Design. Secondly, we have analysed three cases from industrial practice, which show that a conscious and integrated design of product and package has positive logistics effects, whereas neglecting this issue might...... result in higher costs and quality problems. On the basis of these cases we have made an initial cross-case analysis, which indicates that it is possible to develop the terminology and methodology for Integrated Product and Package Design....
Effects of the van der Waals Force on the Dynamics Performance for a Micro Resonant Pressure Sensor
Directory of Open Access Journals (Sweden)
Lizhong Xu
2016-01-01
Full Text Available The micro resonant pressure sensor outputs the frequency signals where the distortion does not take place in a long distance transmission. As the dimensions of the sensor decrease, the effects of the van der Waals forces should be considered. Here, a coupled dynamic model of the micro resonant pressure sensor is proposed and its coupled dynamic equation is given in which the van der Waals force is considered. By the equation, the effects of the van der Waals force on the natural frequencies and vibration amplitudes of the micro resonant pressure sensor are investigated. Results show that the natural frequency and the vibrating amplitudes of the micro resonant pressure sensor are affected significantly by van der Waals force for a small clearance between the film and the base plate, a small initial tension stress of the film, and some other conditions.
Vetoshkin, Evgeny; Babikov, Dmitri
2007-09-28
For the first time Feshbach-type resonances important in recombination reactions are characterized using the semiclassical wave packet method. This approximation allows us to determine the energies, lifetimes, and wave functions of the resonances and also to observe a very interesting correlation between them. Most important is that this approach permits description of a quantum delta-zero-point energy effect in recombination reactions and reproduces the anomalous rates of ozone formation.
International Nuclear Information System (INIS)
Matsuda, Y.; Smith, G.R.; Cohen, R.H.
1989-01-01
Efficiency of current drive by electron cyclotron waves is investigated numerically by a bounce-averaged Fokker-Planck code to ellucidate the effects of momentum transfer from resonant to bulk-electrons, finite bulk temperature relative to the energy of resonant electrons, and trapped electrons. Comparisons are made with existing theories to assess their validity and quantitative difference between theory and code results. Difference of nearly a factor of 2 was found in efficiency between some theory and code results. (author)
Creep and shrinkage effects on integral abutment bridges
Munuswamy, Sivakumar
Integral abutment bridges provide bridge engineers an economical design alternative to traditional bridges with expansion joints owing to the benefits, arising from elimination of expensive joints installation and reduced maintenance cost. The superstructure for integral abutment bridges is cast integrally with abutments. Time-dependent effects of creep, shrinkage of concrete, relaxation of prestressing steel, temperature gradient, restraints provided by abutment foundation and backfill and statical indeterminacy of the structure introduce time-dependent variations in the redundant forces. An analytical model and numerical procedure to predict instantaneous linear behavior and non-linear time dependent long-term behavior of continuous composite superstructure are developed in which the redundant forces in the integral abutment bridges are derived considering the time-dependent effects. The redistributions of moments due to time-dependent effects have been considered in the analysis. The analysis includes nonlinearity due to cracking of the concrete, as well as the time-dependent deformations. American Concrete Institute (ACI) and American Association of State Highway and Transportation Officials (AASHTO) models for creep and shrinkage are considered in modeling the time dependent material behavior. The variations in the material property of the cross-section corresponding to the constituent materials are incorporated and age-adjusted effective modulus method with relaxation procedure is followed to include the creep behavior of concrete. The partial restraint provided by the abutment-pile-soil system is modeled using discrete spring stiffness as translational and rotational degrees of freedom. Numerical simulation of the behavior is carried out on continuous composite integral abutment bridges and the deformations and stresses due to time-dependent effects due to typical sustained loads are computed. The results from the analytical model are compared with the
Quantum delta-kicked rotor: the effect of amplitude noise on the quantum resonances
Brouard, S
2003-01-01
We study analytically the effect of amplitude noise on the quantum resonances of an atom optics realization of the delta-kicked rotor. Noise is shown to add a time growth to the 'deterministic' energy and to induce a time increasing spreading in the momentum distribution; exact results are given for both effects. The ballistic peaks characteristic of the noiseless distribution for particular initial conditions broaden and eventually vanish, whereas the associated quadratic growth of energy persists; at large times, the survival probability decays as t sup - sup 1. Moreover, the nonexponential 'localization' linked to different initial conditions is gradually destroyed. Features specific to Gaussian noise, white and coloured, are analysed. The feasibility of experimental tests of these effects is discussed.
Effect of metal coating and residual stress on the resonant frequency ...
Indian Academy of Sciences (India)
CranesSci MEMS Laboratory, Department of Mechanical Engineering, Indian. Institute of ... Finally, it is found that the analytical models give an error of ... As a resonator, the most important characteristics are the resonant frequency and.
Kim, Chang-Wan; Dai, Mai Duc; Eom, Kilho
2016-01-01
We have studied the finite-size effect on the dynamic behavior of graphene resonators and their applications in atomic mass detection using a continuum elastic model such as modified plate theory. In particular, we developed a model based on von Karman plate theory with including the edge stress, which arises from the imbalance between the coordination numbers of bulk atoms and edge atoms of graphene. It is shown that as the size of a graphene resonator decreases, the edge stress depending on the edge structure of a graphene resonator plays a critical role on both its dynamic and sensing performances. We found that the resonance behavior of graphene can be tuned not only through edge stress but also through nonlinear vibration, and that the detection sensitivity of a graphene resonator can be controlled by using the edge stress. Our study sheds light on the important role of the finite-size effect in the effective design of graphene resonators for their mass sensing applications.
High-sensitivity dc field magnetometer using nonlinear resonance magnetoelectric effect
International Nuclear Information System (INIS)
Burdin, D.A.; Chashin, D.V.; Ekonomov, N.A.; Fetisov, Y.K.; Stashkevich, A.A.
2016-01-01
The design and operation principle of dc field magnetometer using nonlinear resonance magnetoelectric effect in a ferromagnetic–piezoelectric structure are described. It is shown that under action of ac pumping magnetic field the structure generates the output voltage containing higher harmonics whose amplitudes depend on the dc magnetic field. Best performance of the device is obtained if the signal of the third harmonics is used for the dc field measurement. The sensitivity can be considerably (by approximately three orders of magnitude) increased if advantage is taken of the acoustic resonance of the structure at this frequency. There exists the optimal pumping field ensuring the highest sensitivity. Further increasing of this field expands the range of measurable dc fields at the expense of deteriorated sensitivity. The magnetometer fabricated on the basis of a planar langatate-Metglas structure had sensitivity up to ~1 V/Oe and allowed detection of the fields as low as ~10"−"5 Oe. - Highlights: • Operational principle and design of new type dc field magnetometer is described. • Magnetometer uses nonlinear magnetoelectric effect in a langatate-Metglas structure. • Magnetometer has sensitivity of ~1 V/Oe and detects fields as low as 10"−"5 Oe. • The proposed magnetometer can compete with well known fluxgate sensors.
High-sensitivity dc field magnetometer using nonlinear resonance magnetoelectric effect
Energy Technology Data Exchange (ETDEWEB)
Burdin, D.A.; Chashin, D.V.; Ekonomov, N.A. [Moscow State University of Information Technologies, Radio Engineering and Electronics, Moscow (Russian Federation); Fetisov, Y.K., E-mail: fetisov@mirea.ru [Moscow State University of Information Technologies, Radio Engineering and Electronics, Moscow (Russian Federation); Stashkevich, A.A. [LSPM (CNRS-UPR 3407), Université Paris 13, Sorbonne Paris Cité, 93430 Villetaneuse (France)
2016-05-01
The design and operation principle of dc field magnetometer using nonlinear resonance magnetoelectric effect in a ferromagnetic–piezoelectric structure are described. It is shown that under action of ac pumping magnetic field the structure generates the output voltage containing higher harmonics whose amplitudes depend on the dc magnetic field. Best performance of the device is obtained if the signal of the third harmonics is used for the dc field measurement. The sensitivity can be considerably (by approximately three orders of magnitude) increased if advantage is taken of the acoustic resonance of the structure at this frequency. There exists the optimal pumping field ensuring the highest sensitivity. Further increasing of this field expands the range of measurable dc fields at the expense of deteriorated sensitivity. The magnetometer fabricated on the basis of a planar langatate-Metglas structure had sensitivity up to ~1 V/Oe and allowed detection of the fields as low as ~10{sup −5} Oe. - Highlights: • Operational principle and design of new type dc field magnetometer is described. • Magnetometer uses nonlinear magnetoelectric effect in a langatate-Metglas structure. • Magnetometer has sensitivity of ~1 V/Oe and detects fields as low as 10{sup −5} Oe. • The proposed magnetometer can compete with well known fluxgate sensors.
Energy Technology Data Exchange (ETDEWEB)
Nurgaliev, T., E-mail: timur@ie.bas.bg [Institute of Electronics, Bulgarian Academy of Sciences, 72 Tsarigradsko Chausse, 1784 Sofia (Bulgaria); Blagoev, B.; Mateev, E.; Neshkov, L. [Institute of Electronics, Bulgarian Academy of Sciences, 72 Tsarigradsko Chausse, 1784 Sofia (Bulgaria); Strbik, V. [Institute of Electrical Engineering, Slovak Academy of Sciences, Dúbravská cesta 9, 841 04 Bratislava (Slovakia); Uspenskaya, L. [Institute of Solid State Physics, Russian Academy of Sciences, 142432 Chernogolovka, Moscow (Russian Federation); Nedkov, I. [Institute of Electronics, Bulgarian Academy of Sciences, 72 Tsarigradsko Chausse, 1784 Sofia (Bulgaria); Chromik, Š. [Institute of Electrical Engineering, Slovak Academy of Sciences, Dúbravská cesta 9, 841 04 Bratislava (Slovakia)
2014-03-15
Highlights: • Current (spin) injection effect in LSMO/YBCO was studied by impedance measurements. • Complex impedance of YBCO increases at current injection from LSMO to YBCO at 77 K. • This increase is due to an increase of the quasiparticle conductivity of YBCO. • Injection does not significantly affect the relaxation time of the quasiparticles. - Abstract: The DC current injection effect from a ferromagnetic (FM) La{sub 0.7}Sr{sub 0.3}MnO{sub 3} (LSMO) to a high temperature superconducting (HTS) Y{sub 1}Ba{sub 2}Cu{sub 3}O{sub 7−x} (YBCO) thin film was investigated by the microwave surface impedance measurements in a FM/HTS structure, formed as a microstrip resonator for improving the sensitivity of the experiments. The quality factor and the resonance frequency of this structure were found to strongly depend on the current strength, injected from the LSMO electrode into the HTS microstrip electrode. The magnetic penetration depth and the quasiparticle conductivity of the HTS component were determined to increase under DC current injection process, which in all probability stimulated breaking of Cooper pairs and led to a decrease of the superfluid concentration and an increase of the normal fluid concentration without significantly affecting the relaxation time of the quasiparticles.
Immediate effects of the Finnish resonance tube method on behavioral dysphonia.
Paes, Sabrina Mazzer; Zambon, Fabiana; Yamasaki, Rosiane; Simberg, Susanna; Behlau, Mara
2013-11-01
To investigate the immediate effects of the Finnish resonance tube method for teachers with behavioral dysphonia. Twenty-five female teachers (m=39.9 years of age) with at least a 5-year history of dysphonia were included. Additional inclusion criteria were the diagnosis of chronic behavioral dysphonia with an indication for speech therapy and the absence of any prior speech therapy. Subjects produced three sets of 10 tokens of sustained phonation with a 1-minute rest interval between tokens into a 27-cm glass tube immersed in at least 2 cm of water. Voice samples were recorded before and after these sets. The effects of these exercises were evaluated by self-assessment, auditory perceptual analysis, and acoustic evaluation involving extraction of fundamental frequency and visual spectrographic analysis. Sixty-eight percent of the teachers reported increased phonatory comfort and 52% reported improved voice quality after performing the exercises. Perceptual analysis indicated improved voice quality in the samples of counting numbers, confirmed by decreased instability, subharmonics, noise in high frequencies, and the tendency for reduced low frequency noise on spectrographic evaluation. Additionally, mean fundamental frequency decreased. The Finnish resonance tube method increased phonatory comfort and vocal changes suggestive diminished hyperfunction. Copyright © 2013 The Voice Foundation. Published by Mosby, Inc. All rights reserved.
Gosar, A.
2010-04-01
The town of Kobarid is located in one of three areas with the highest seismic hazard in Slovenia. It was hit by several 1976-1977 Friuli sequence earthquakes and recently by the 1998 and 2004 Krn Mountains earthquakes which caused damage of intensity up to VII EMS-98 scale. The town is located in a small basin filled with heterogeneous glaciofluvial Quaternary sediments in which site effects due to soft sediments are expected. The existing microzonation which is based on surface geological data only is inadequate, and no borehole or geophysical data are available in the basin that would allow a modelling approach of site effects assessment. The microtremor horizontal-to-vertical spectral ratio (HVSR) method was therefore applied in order to assess the fundamental frequency of the sediments. Investigations were performed on a 100×100 m dense grid and 106 free-field measurements acquired. Clear HVSR peaks were obtained in the majority of the surveyed area. The eastern part of the basin is characterized by two well separated peaks which indicate distinct shallow and deep impedance contrasts. The iso-frequency map of sediments shows a distribution in a broad range of 1.8-22.2 Hz. The observed frequencies can be related to the total thickness of Quaternary sediments (sand, gravel) in the western part of the basin only. They are deposited over bedrock built of Cretaceous flysch. In the eastern part the obtained fundamental frequencies are influenced by the presence of a shallow conglomerate layer inside sandy gravel or lacustrine chalk. The extent of these layers was not known before. Microtremor measurements were also performed inside 19 characteristic buildings of various heights (from two to four stories), and longitudinal and transverse fundamental frequencies determined from amplitude spectra. A potential of soil-structure resonance was assessed by comparing building frequencies with the free-field sediments frequencies derived from the iso-frequency map. For two
Site effects and soil-structure resonance study in the Kobarid basin (NW Slovenia using microtremors
Directory of Open Access Journals (Sweden)
A. Gosar
2010-04-01
Full Text Available The town of Kobarid is located in one of three areas with the highest seismic hazard in Slovenia. It was hit by several 1976–1977 Friuli sequence earthquakes and recently by the 1998 and 2004 Krn Mountains earthquakes which caused damage of intensity up to VII EMS-98 scale. The town is located in a small basin filled with heterogeneous glaciofluvial Quaternary sediments in which site effects due to soft sediments are expected. The existing microzonation which is based on surface geological data only is inadequate, and no borehole or geophysical data are available in the basin that would allow a modelling approach of site effects assessment. The microtremor horizontal-to-vertical spectral ratio (HVSR method was therefore applied in order to assess the fundamental frequency of the sediments. Investigations were performed on a 100×100 m dense grid and 106 free-field measurements acquired. Clear HVSR peaks were obtained in the majority of the surveyed area. The eastern part of the basin is characterized by two well separated peaks which indicate distinct shallow and deep impedance contrasts. The iso-frequency map of sediments shows a distribution in a broad range of 1.8–22.2 Hz. The observed frequencies can be related to the total thickness of Quaternary sediments (sand, gravel in the western part of the basin only. They are deposited over bedrock built of Cretaceous flysch. In the eastern part the obtained fundamental frequencies are influenced by the presence of a shallow conglomerate layer inside sandy gravel or lacustrine chalk. The extent of these layers was not known before. Microtremor measurements were also performed inside 19 characteristic buildings of various heights (from two to four stories, and longitudinal and transverse fundamental frequencies determined from amplitude spectra. A potential of soil-structure resonance was assessed by comparing building frequencies with the free-field sediments frequencies derived from the iso
The probable effect of integrated reporting on audit quality
Directory of Open Access Journals (Sweden)
Tamer A. El Nashar
2016-06-01
Full Text Available This paper examines a probable effect of integrated reporting on improving the audit quality of organizations. I correlate the hypothesis of this paper in relation to the current trends of protecting the economies, the financial markets and the societies. I predict an improvement of the audit quality, as a result to an estimated percentage of organizations’ reliance on the integrated reporting in their accountability perspective. I used a decision tree and a Bayes’ theorem approach, to predict the probabilities of the significant effect on improving the auditing quality. I find the overall result of this paper, indicates that the probability of organizations to rely on the integrated reporting by a significant percentage, predicts also a significant improvement in audit quality.
A Cost-Effective Design and Analysis of Full Bridge LLC Resonant Converter
Kaibalya Prasad Panda; Sreyasee Rout
2016-01-01
LLC (Inductor-inductor-capacitor) resonant converter has lots of advantages over other type of resonant converters which include high efficiency, more reliable and have high power density. This paper presents the design and analysis of a full bridge LLC resonant converter. In addition to the operational principle, the ZVS and ZCS conditions are also explained with the DC characteristics. Simulation of the LLC resonant converter is performed in MATLAB/ Simulink and the practical prototype setu...
An Integrated Model for Effective Knowledge Management in Chinese Organizations
An, Xiaomi; Deng, Hepu; Wang, Yiwen; Chao, Lemen
2013-01-01
Purpose: The purpose of this paper is to provide organizations in the Chinese cultural context with a conceptual model for an integrated adoption of existing knowledge management (KM) methods and to improve the effectiveness of their KM activities. Design/methodology/approaches: A comparative analysis is conducted between China and the western…
Effect of integrated pest management farmer field school (IPMFFS ...
African Journals Online (AJOL)
This research aimed to explore the effect of the Integrated Pest Management Farmer Field School (IPMFFS), on farmer knowledge, farmer group's ability, process of adoption and diffusion of IPM in Jember district. The population of the research was 556 farmer groups consisting of 22.240 farmers engaged in the IPMFFS in ...
Exploring cost-effective maize integrated weed management ...
African Journals Online (AJOL)
Several production constraints have led to low yields (< 2.5 t ha-1) in maize (Zea mays L.) inUganda, among which are weeds. This study investigated the most cost-effective integrated weedmanagement (IWM) approach in maize in eastern Uganda. An experiment was conducted atIkulwe station, Mayuge in 2011 and 2012 ...
Planck 2015 results: XXI. The integrated Sachs-Wolfe effect
DEFF Research Database (Denmark)
Ade, P. A R; Aghanim, N.; Arnaud, M.
2016-01-01
This paper presents a study of the integrated Sachs-Wolfe (ISW) effect from the Planck 2015 temperature and polarization data release. This secondary cosmic microwave background (CMB) anisotropy caused by the large-scale time-evolving gravitational potential is probed from different perspectives....
Effects of Spatial and Selective Attention on Basic Multisensory Integration
Gondan, Matthias; Blurton, Steven P.; Hughes, Flavia; Greenlee, Mark W.
2011-01-01
When participants respond to auditory and visual stimuli, responses to audiovisual stimuli are substantially faster than to unimodal stimuli (redundant signals effect, RSE). In such tasks, the RSE is usually higher than probability summation predicts, suggestive of specific integration mechanisms underlying the RSE. We investigated the role of…
412 The Effects of Integrating Laboratory Work with Theory on ...
African Journals Online (AJOL)
User
2010-10-17
Oct 17, 2010 ... This study was an attempt to investigate the effects of integrating ... which is antithesis of true science. ... Where O1 and O3 are pretest measurement of experimental and ... schools in the study area formed the sample for the study. ... questions drawn from the selected physics concepts, elasticity, simple.
Effects of Video Modeling on Treatment Integrity of Behavioral Interventions
DiGennaro-Reed, Florence D.; Codding, Robin; Catania, Cynthia N.; Maguire, Helena
2010-01-01
We examined the effects of individualized video modeling on the accurate implementation of behavioral interventions using a multiple baseline design across 3 teachers. During video modeling, treatment integrity improved above baseline levels; however, teacher performance remained variable. The addition of verbal performance feedback increased…
Critical current in the Integral Quantum Hall Effect
International Nuclear Information System (INIS)
Kostadinov, I.Z.
1985-11-01
A multiparticle theory of the Integral Quantum Hall Effect (IQHE) was constructed operating with pairs wave function as an order parameter. The IQHE is described with bosonic macroscopic states while the fractional QHE with fermionic ones. The calculation of the critical current and Hall conductivity temperature dependence is presented. (author)
Integrating Professional Development across the Curriculum: An Effectiveness Study
Ciarocco, Natalie J.; Dinella, Lisa M.; Hatchard, Christine J.; Valosin, Jayde
2016-01-01
The current study empirically tested the effectiveness of a modular approach to integrating professional development across an undergraduate psychology curriculum. Researchers conducted a two-group, between-subjects experiment on 269 undergraduate psychology students assessing perceptions of professional preparedness and learning. Analysis…
Integrative Strategy for Effective Teaching of Alternating Circuits in ...
African Journals Online (AJOL)
One of the reasons advanced for the low enrolment and achievement of students in Physics at both secondary and post-secondary schools is poor teaching strategies used by teachers of Physics particularly in teaching Physics concepts classified by students as being difficult. In this paper, integrative strategy for effective ...
Effects of integration time on in-water radiometric profiles.
D'Alimonte, Davide; Zibordi, Giuseppe; Kajiyama, Tamito
2018-03-05
This work investigates the effects of integration time on in-water downward irradiance E d , upward irradiance E u and upwelling radiance L u profile data acquired with free-fall hyperspectral systems. Analyzed quantities are the subsurface value and the diffuse attenuation coefficient derived by applying linear and non-linear regression schemes. Case studies include oligotrophic waters (Case-1), as well as waters dominated by Colored Dissolved Organic Matter (CDOM) and Non-Algal Particles (NAP). Assuming a 24-bit digitization, measurements resulting from the accumulation of photons over integration times varying between 8 and 2048ms are evaluated at depths corresponding to: 1) the beginning of each integration interval (Fst); 2) the end of each integration interval (Lst); 3) the averages of Fst and Lst values (Avg); and finally 4) the values weighted accounting for the diffuse attenuation coefficient of water (Wgt). Statistical figures show that the effects of integration time can bias results well above 5% as a function of the depth definition. Results indicate the validity of the Wgt depth definition and the fair applicability of the Avg one. Instead, both the Fst and Lst depths should not be adopted since they may introduce pronounced biases in E u and L u regression products for highly absorbing waters. Finally, the study reconfirms the relevance of combining multiple radiometric casts into a single profile to increase precision of regression products.
An attempt to explain the uranium 238 effective capture integral discrepancy
International Nuclear Information System (INIS)
Tellier, Henry; Grandotto-Biettoli, Marc; Vanuxeem, Jacqueline
1979-02-01
Up to now, there was a discrepancy between the computed value and the measured value of the uranium 238 effective capture integral. The former has been always greater than the latter. For this reason, the reactor physicists have used an adjustment of the computed value. Nowadays the accuracy of the cross sections knowledge is increased and the reactors computation codes are almost exact. Such an adjustment is no more justified. Recently several new measurements of the resonance parameters were carried out and the use of a multilevel formalism was suggested to compute the uranium 238 cross sections. It is shown in this work that the simultaneous use of recent parameters and Reich and Moore formalism explain the discrepancy. For the thermal neutron reactors, two thirds of this discrepancy are explained by the neutron data and the last third by the multilevel formalism [fr
DEFF Research Database (Denmark)
Emerek, Ruth
2004-01-01
Bidraget diskuterer de forskellige intergrationsopfattelse i Danmark - og hvad der kan forstås ved vellykket integration......Bidraget diskuterer de forskellige intergrationsopfattelse i Danmark - og hvad der kan forstås ved vellykket integration...
International Nuclear Information System (INIS)
Koike, Masafumi; Ota, Toshihiko; Saito, Masako; Sato, Joe
2016-01-01
Effects of the inhomogeneous matter density on the three-generation neutrino oscillation probability are analyzed. Realistic profile of the matter density is expanded into a Fourier series. Taking in the Fourier modes one by one, we demonstrate that each mode has its corresponding target energy. The high Fourier mode selectively modifies the oscillation probability of the low-energy region. This rule is well described by the parametric resonance between the neutrino oscillation and the matter effect. The Fourier analysis gives a simple guideline to systematically control the uncertainty of the oscillation probability caused by the uncertain density of matter. Precise analysis of the oscillation probability down to the low-energy region requires accurate evaluation of the Fourier coefficients of the matter density up to the corresponding high modes.
DEFF Research Database (Denmark)
Zhukovsky, Sergei V.; Babicheva, Viktoriia; Uskov, Alexander
2014-01-01
We theoretically study the characteristics of photoelectron emission in plasmonic nanoparticle arrays. Nanoparticles are partially embedded in a semiconductor, forming Schottky barriers at metal/semiconductor interfaces through which photoelectrons can tunnel from the nanoparticle...... into the semiconductor; photodetection in the infrared range, where photon energies are below the semiconductor band gap (insufficient for band-to-band absorption in semiconductor), is therefore possible. The nanoparticles are arranged in a sparse rectangular lattice so that the wavelength of the lattice......-induced Rayleigh anomalies can overlap the wavelength of the localized surface plasmon resonance of the individual particles, bringing about collective effects from the nanoparticle array. Using full-wave numerical simulations, we analyze the effects of lattice constant, embedding depth, and refractive index step...
International Nuclear Information System (INIS)
Allen, Lucy R; Paci, Emanuele
2010-01-01
Fluorescence resonance energy transfer is a powerful technique which is often used to probe the properties of proteins and complex macromolecules. The technique relies on relatively large fluorescent dyes which are engineered into the molecule of interest. In the case of small proteins, these dyes may affect the stability of the protein, and modify the folding kinetics and the folding mechanisms which are being probed. Here we use atomistic simulation to investigate the effect that commonly used fluorescent dyes have on the folding of a four-helix bundle protein. We show that, depending on where the dyes are attached, their effect on the kinetic and thermodynamic properties of the protein may be significant. We find that, while the overall folding mechanism is not affected by the dyes, they can destabilize, or even stabilize, intermediate states.
Resonating-group study and importance of exchange effects in the α + 6Li system
International Nuclear Information System (INIS)
Suenkel, W.; Tang, Y.C.
1979-01-01
The resonating-group method in the one-channel approximation is used to investigate the α + 6 Li system. The result shows that, especially at relatively high energies, reasonable agreement with experiment can be obtained. In particular, the cross section rise in the backward angular region is well reproduced. The effects of internuclear antisymmetrization, represented by various nucleon-exchange terms in the kernel function, are also carefully examined. Some of the interesting findings are that the blocking effect is quite significant in this system and the two-exchange terms (sometimes even the three-exchange terms) seem to have only minor influence on the scattering cross section. 7 figures, 1 table
DEFF Research Database (Denmark)
Hanni, Matti; Lantto, Perttu; Ilias, Miroslav
2007-01-01
Relativistic effects on the 129Xe nuclear magnetic resonance shielding and 131Xe nuclear quadrupole coupling (NQC) tensors are examined in the weakly bound Xe2 system at different levels of theory including the relativistic four-component Dirac-Hartree-Fock (DHF) method. The intermolecular...... interaction-induced binary chemical shift d, the anisotropy of the shielding tensor ?s, and the NQC constant along the internuclear axis ?ll are calculated as a function of the internuclear distance. DHF shielding calculations are carried out using gauge-including atomic orbitals. For comparison, the full...... is obtained for d and ?s in Xe2. For these properties, the currently most complete theoretical description is obtained by a piecewise approximation where the uncorrelated relativistic DHF results obtained close to the basis-set limit are corrected, on the one hand, for NR correlation effects and, on the other...
Nonlinear Modeling and Simulation of Thermal Effects in Microcantilever Resonators Dynamic
International Nuclear Information System (INIS)
Tadayon, M A; Sayyaadi, H; Jazar, G Nakhaie
2006-01-01
Thermal dependency of material characteristics in micro electromechanical systems strongly affects their performance, design, and control. Hence, it is essential to understand and model that in MEMS devices to optimize their designs. A thermal phenomenon introduces two main effects: damping due to internal friction, and softening due to Young modulus temperature relation. Based on some reported theoretical and experimental results, we model the thermal phenomena and use two Lorentzian functions to describe the restoring and damping forces caused by thermal phenomena. In order to emphasize the thermal effects, a nonlinear model of the MEMS, by considering capacitor nonlinearity, have been used. The response of the system is developed by employing multiple time scales perturbation method on nondimensionalized form of equations. Frequency response, resonant frequency and peak amplitude are examined for variation of dynamic parameters involved
Observation of the E2 nuclear resonance effect in some pionic atoms
International Nuclear Information System (INIS)
Leon, M.; Bradbury, J.N.; Gram, P.A.M.; Hutson, R.L.; Schillaci, M.E.; Hargrove, C.K.
1979-01-01
The E2 nuclear resonance effect has been studied in the pionic atoms of 48 Ti, 104 Ru, 110 Pd, 111 112 Cd, and 150 Sm. For pionic 111 112 Cd, where the ''mixed-in'' level is directly observable, the measured effect agrees very well with theory. For pionic 110 Pd, the measurement confirms for the first time the prediction of Ericson et al. that the P-wave π-nucleus interaction becomes repulsive for large enough Z, but also implies a P-wave absorptive width smaller than predicted by standard optical potentials. The experimental results for 104 Ru and 150 Sm agree with simple theoretical model, while that for 48 Ti does not. (Auth.)
The effect of materials properties on the Q of high Tc helical and coaxial resonators
International Nuclear Information System (INIS)
Peterson, G.E.; Fleming, D.A.; Johnson, D.W. Jr.; Rhodes, W.W.
1990-01-01
High T c helical and coaxial resonators have applications in U.H.F. radio receivers. We have employed a variety of techniques to study the superconducting materials used to form such resonators. These include, X-ray diffraction, SEM, density, dilatometry and sedigraph. We have correlated our data with resonator Q and frequency and have determined optimum conditions for highest Q. Our best resonators perform better than their all copper counterparts by a factor of 10 at 77K and at frequencies below 1,000 MHz. We have used these resonators in local oscillators and Butterworth filters in U.H.F. receivers
Energy Technology Data Exchange (ETDEWEB)
Kang, Kyoungho; Seokcho; Park, Hyunsik; Choi, Namhyun; Park, Yusun; Kim, Jongrok; Bae, Byounguhn; Kim, Yeonsik; Choi, Kiyong; Song, Chulhwa [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)
2013-05-15
In this study, thermal-hydraulic integral effect test with the ATLAS (Advanced Thermal-Hydraulic Test Loop for Accident Simulation) was performed for simulating a failure of CEDM penetration nozzle. The main objectives of the present test were not only to provide physical insight into the system response during a failure of CEDM penetration nozzle but also to establish an integral effect test database for the validation of the safety analysis codes. Furthermore, present experimental data were utilized to resolve the safety issue raised by the PWSCC at the CEDM penetration nozzle of the YGN-3. Thermal-hydraulic integral effect test with the ATLAS was performed for simulating a failure of CEDM penetration nozzle. Failure of two penetration nozzles of the CEDM in the APR1400 was simulated. Initial and boundary conditions were determined with respect to the reference conditions of the APR1400. However, with an aim of corresponding to the YGN-3 situation, the safety injection water was supplied via CLI mode. Compared to the cold leg break SBLOCA, the consequences of the event were milder in terms of a loop seal clearance, break flow rate, collapsed water level, and PCT. This could be mainly attributed to the small break flow rate in case of the failure in the RPV upper head. Present experimental data were utilized to resolve the safety issue raised by the PWSCC at the CEDM penetration nozzle of the YGN-3.
O'Dell, Michael W; Villanueva, Mark; Creelman, Carly; Telhan, Gaurav; Nestor, Jaclyn; Hentel, Keith D; Ballon, Douglas; Dyke, Jonathan P
2017-12-01
Although important for dosing and dilution, there are few data describing botulinum toxin (BT) movement in human muscle. To better understand BT movement within human muscle. Proof-of-concept study with descriptive case series. Outpatient academic practice. Five subjects with stroke who were BT naive with a mean age of 60.4 ± 14 years and time poststroke of 4.6 ± 3.7 years. Three standardized injections were given to the lateral gastrocnemius muscle (LGM): 2 contained 25 units (U) of onabotulinumtoxinA (Botox) in 0.25 mL of saline solution and the third 0.25 mL of saline solution only. The tibialis anterior muscle (TAM) was not injected in any subject. A leg magnetic resonance image was obtained at baseline, 2 months, and 3 months later with a 3.0 Tesla Siemens scanner. Three muscles, the LGM, lateral soleus muscle (LSM), and TAM, were manually outlined on the T2 mapping sequence at each time point. A histogram of T2 relaxation times (T2-RT) for all voxels at baseline was used to calculate a mean and standard deviation (SD) T2-RT for each muscle. Botulinum toxin muscle effect (BTME) at 2 months and 3 months was defined as a subject- and muscle-specific T2-RT voxel threshold ≥3 SD above the baseline mean at or near BT injection sites. BTME volume for each leg magnetic resonance imaging slice at 3 time points and 3 muscles for all subjects. One subject missed the 3-month scan, leaving 18 potential observations of BTME. Little to no BTME effect was seen in the noninjected TAM. A BTME was detected in the LGM in 13 of 18 possible observations, and no effect was detected in 5 observations. Possible BTME effect was seen in the LSM in 3 subjects due to either diffusion through fascia or needle misplacement. Volume of BTME, as defined here, appeared to be substantially greater than the 0.25-mL injection volume. This descriptive case series is among the first attempts to quantify BTME within human muscle. Our findings are preliminary and are limited by a few
Effect of dynamical phase on the resonant interaction among tsunami edge wave modes
Geist, Eric L.
2018-01-01
Different modes of tsunami edge waves can interact through nonlinear resonance. During this process, edge waves that have very small initial amplitude can grow to be as large or larger than the initially dominant edge wave modes. In this study, the effects of dynamical phase are established for a single triad of edge waves that participate in resonant interactions. In previous studies, Jacobi elliptic functions were used to describe the slow variation in amplitude associated with the interaction. This analytical approach assumes that one of the edge waves in the triad has zero initial amplitude and that the combined phase of the three waves φ = θ1 + θ2 − θ3 is constant at the value for maximum energy exchange (φ = 0). To obtain a more general solution, dynamical phase effects and non-zero initial amplitudes for all three waves are incorporated using numerical methods for the governing differential equations. Results were obtained using initial conditions calculated from a subduction zone, inter-plate thrust fault geometry and a stochastic earthquake slip model. The effect of dynamical phase is most apparent when the initial amplitudes and frequencies of the three waves are within an order of magnitude. In this case, non-zero initial phase results in a marked decrease in energy exchange and a slight decrease in the period of the interaction. When there are large differences in frequency and/or initial amplitude, dynamical phase has less of an effect and typically one wave of the triad has very little energy exchange with the other two waves. Results from this study help elucidate under what conditions edge waves might be implicated in late, large-amplitude arrivals.
Effect of Dynamical Phase on the Resonant Interaction Among Tsunami Edge Wave Modes
Geist, Eric L.
2018-04-01
Different modes of tsunami edge waves can interact through nonlinear resonance. During this process, edge waves that have very small initial amplitude can grow to be as large or larger than the initially dominant edge wave modes. In this study, the effects of dynamical phase are established for a single triad of edge waves that participate in resonant interactions. In previous studies, Jacobi elliptic functions were used to describe the slow variation in amplitude associated with the interaction. This analytical approach assumes that one of the edge waves in the triad has zero initial amplitude and that the combined phase of the three waves φ = θ 1 + θ 2 - θ 3 is constant at the value for maximum energy exchange ( φ = 0). To obtain a more general solution, dynamical phase effects and non-zero initial amplitudes for all three waves are incorporated using numerical methods for the governing differential equations. Results were obtained using initial conditions calculated from a subduction zone, inter-plate thrust fault geometry and a stochastic earthquake slip model. The effect of dynamical phase is most apparent when the initial amplitudes and frequencies of the three waves are within an order of magnitude. In this case, non-zero initial phase results in a marked decrease in energy exchange and a slight decrease in the period of the interaction. When there are large differences in frequency and/or initial amplitude, dynamical phase has less of an effect and typically one wave of the triad has very little energy exchange with the other two waves. Results from this study help elucidate under what conditions edge waves might be implicated in late, large-amplitude arrivals.
Effect of Dynamical Phase on the Resonant Interaction Among Tsunami Edge Wave Modes
Geist, Eric L.
2018-02-01
Different modes of tsunami edge waves can interact through nonlinear resonance. During this process, edge waves that have very small initial amplitude can grow to be as large or larger than the initially dominant edge wave modes. In this study, the effects of dynamical phase are established for a single triad of edge waves that participate in resonant interactions. In previous studies, Jacobi elliptic functions were used to describe the slow variation in amplitude associated with the interaction. This analytical approach assumes that one of the edge waves in the triad has zero initial amplitude and that the combined phase of the three waves φ = θ 1 + θ 2 - θ 3 is constant at the value for maximum energy exchange (φ = 0). To obtain a more general solution, dynamical phase effects and non-zero initial amplitudes for all three waves are incorporated using numerical methods for the governing differential equations. Results were obtained using initial conditions calculated from a subduction zone, inter-plate thrust fault geometry and a stochastic earthquake slip model. The effect of dynamical phase is most apparent when the initial amplitudes and frequencies of the three waves are within an order of magnitude. In this case, non-zero initial phase results in a marked decrease in energy exchange and a slight decrease in the period of the interaction. When there are large differences in frequency and/or initial amplitude, dynamical phase has less of an effect and typically one wave of the triad has very little energy exchange with the other two waves. Results from this study help elucidate under what conditions edge waves might be implicated in late, large-amplitude arrivals.
Representation of states on effect-tribes and effect algebras by integrals
Dvurečenskij, Anatolij
2011-02-01
We describe σ-additive states on effect-tribes by integrals. Effect-tribes are monotone σ-complete effect algebras of functions where operations are defined pointwise. Then we show that every state on an effect algebra is an integral through a Borel regular probability measure. Finally, we show that every σ-convex combination of extremal states on a monotone σ-complete effect algebra is a Jauch-Piron state.
Enhancement of optical Kerr effect in quantum-cascade lasers with multiple resonance levels.
Bai, Jing; Citrin, D S
2008-08-18
In this paper, we investigated the optical Kerr lensing effect in quantum-cascade lasers with multiple resonance levels. The Kerr refractive index n2 is obtained through the third-order susceptibility at the fundamental frequency chi(3)( omega; omega, omega,-omega). Resonant two-photon processes are found to have almost equal contributions to chi(3)( omega; omega, omega,-omega) as the single-photon processes, which result in the predicted enhancement of the positive nonlinear (Kerr) refractive index, and thus may enhance mode-locking of quantum-cascade lasers. Moreover, we also demonstrate an isospectral optimization strategy for further improving n2 through the band-structure design, in order to boost the multimode performance of quantum-cascade lasers. Simulation results show that the optimized stepwise multiple-quantum-well structure has n2 approximately 10-8 cm2/W, a twofold enhancement over the original flat quantum-well structure. This leads to a refractive-index change (delta)n of about 0.01, which is at the upper bound of those reported for typical Kerr medium. This stronger Kerr refractive index may be important for quantum-cascade lasers ultimately to demonstrate self-mode-locking.
Broadband non-polarizing beam splitter based on guided mode resonance effect
International Nuclear Information System (INIS)
Ma Jian-Yong; Xu Cheng; Qiang Ying-Huai; Zhu Ya-Bo
2011-01-01
A broadband non-polarizing beam splitter (NPBS) operating in the telecommunication C+L band is designed by using the guided mode resonance effect of periodic silicon-on-insulator (SOI) elements. It is shown that this double layer SOI structure can provide ∼50/50 beam ratio with the maximum divergences between reflection and transmission being less than 8% over the spectrum of 1.4 μm∼1.7 μm and 1% in the telecommunication band for both TE and TM polarizations. The physical basis of this broadband non-polarizing property is on the simultaneous excitation of the TE and TM strong modulation waveguide modes near the designed spectrum band. Meanwhile, the electric field distributions for both TE and TM polarizations verify the resonant origin of spectrum in the periodic SOI structure. Furthermore, it is demonstrated with our calculations that the beam splitter proposed here is tolerant to the deviations of incident angle and structure parameters, which make it very easy to be fabricated with current IC technology. (electromagnetism, optics, acoustics, heat transfer, classical mechanics, and fluid dynamics)
Tian, S Y; Zou, L; Quan, X; Zhang, Y; Xue, F S; Ye, T H
2010-06-01
To assess the effects of midazolam on explicit and implicit memories, 12 volunteers were randomly divided into the two groups: one with an Observer's Assessment of Alertness/Sedation score of 3 (mild sedation) and one with a score of 1 (deep sedation). Blood oxygen-level-dependent functional magnetic resonance imaging was measured before and during an auditory stimulus, then with midazolam sedation, and then during a second auditory stimulus with continuous midazolam sedation. After 4 h, explicit and implicit memories were assessed. There was no evidence of explicit memory at the two levels of midazolam sedation. Implicit memory was retained at a mild level of midazolam sedation but absent at a deep level of midazolam sedation. At a mild level of midazolam sedation, activation of all brain areas by auditory stimulus (as measured by functional magnetic resonance imaging) was uninhibited. However, a deep level of midazolam sedation depressed activation of the superior temporal gyrus by auditory stimulus. We conclude that midazolam does not abolish implicit memory at a mild sedation level, but can abolish both explicit and implicit memories at a deep sedation level. The superior temporal gyrus may be one of the target areas.
Broadband non-polarizing beam splitter based on guided mode resonance effect
Ma, Jian-Yong; Xu, Cheng; Qiang, Ying-Huai; Zhu, Ya-Bo
2011-10-01
A broadband non-polarizing beam splitter (NPBS) operating in the telecommunication C+L band is designed by using the guided mode resonance effect of periodic silicon-on-insulator (SOI) elements. It is shown that this double layer SOI structure can provide ~50/50 beam ratio with the maximum divergences between reflection and transmission being less than 8% over the spectrum of 1.4 μm~1.7 μm and 1% in the telecommunication band for both TE and TM polarizations. The physical basis of this broadband non-polarizing property is on the simultaneous excitation of the TE and TM strong modulation waveguide modes near the designed spectrum band. Meanwhile, the electric field distributions for both TE and TM polarizations verify the resonant origin of spectrum in the periodic SOI structure. Furthermore, it is demonstrated with our calculations that the beam splitter proposed here is tolerant to the deviations of incident angle and structure parameters, which make it very easy to be fabricated with current IC technology.
Solid-state effects on thermal-neutron cross sections and on low-energy resonances
International Nuclear Information System (INIS)
Harvey, J.A.; Mook, H.A.; Hill, N.W.; Shahal, O.
1982-01-01
The neutron total cross sections of several single crystals (Si, Cu, sapphire), several polycrystalline samples (Cu, Fe, Be, C, Bi, Ta), and a fine-powder copper sample have been measured from 0.002 to 5 eV. The Cu powder and polycrystalline Fe, Be and C data exhibit the expected abrupt changes in cross section. The cross section of the single crystal of Si is smooth with only small broad fluctuations. The data on two single Cu crystals, the sapphire crystal, cast Bi, and rolled samples of Ta and Cu have many narrow peaks approx. 10 -3 eV wide. High resolution (0.3%) transmission measurements were made on the 1.057-eV resonance in 240 Pu and the 0.433-eV resonance in 180 Ta, both at room and low temperatures to study the effects of crystal binding. Although the changes in Doppler broadening with temperature were apparent, no asymmetries due to a recoilless contribution were observed
Stol, D.; Badenbroek, I.; Hollander, M.; Nielen, M.; Schellevis, F.; Wit, N. de
2014-01-01
The effectiveness and cost-effectiveness of an integrated cardiometabolic risk assessment and treatment program in primary care (the INTEGRATE study): a stepped-wedge randomized controlled trial protocol. Rationale: The increasing prevalence of cardiometabolic disease (CMD), including cardiovascular
Energy Technology Data Exchange (ETDEWEB)
Weichsel, T., E-mail: tim.weichsel@fep.fraunhofer.de; Hartung, U.; Kopte, T. [Fraunhofer Institute for Organic Electronics, Electron Beam and Plasma Technology FEP, 01277 Dresden (Germany); Zschornack, G. [Institute of Solid State Physics, Dresden University of Technology, 01062 Dresden, Germany and Helmholtz-Zentrum Dresden-Rossendorf e.V., Institute of Ion Beam Physics and Materials Research, Dresden (Germany); Kreller, M.; Philipp, A. [DREEBIT GmbH, 01900 Grossroehrsdorf (Germany)
2015-09-15
A metal ion source prototype has been developed: a combination of magnetron sputter technology with 2.45 GHz electron cyclotron resonance (ECR) ion source technology—a so called magnetron ECR ion source (MECRIS). An integrated ring-shaped sputter magnetron with an Al target is acting as a powerful metal atom supply in order to produce an intense current of singly charged metal ions. Preliminary experiments show that an Al{sup +} ion current with a density of 167 μA/cm{sup 2} is extracted from the source at an acceleration voltage of 27 kV. Spatially resolved double Langmuir probe measurements and optical emission spectroscopy were used to study the plasma states of the ion source: sputter magnetron, ECR, and MECRIS plasma. Electron density and temperature as well as Al atom density were determined as a function of microwave and sputter magnetron power. The effect of ECR heating is strongly pronounced in the center of the source. There the electron density is increased by one order of magnitude from 6 × 10{sup 9} cm{sup −3} to 6 × 10{sup 10} cm{sup −3} and the electron temperature is enhanced from about 5 eV to 12 eV, when the ECR plasma is ignited to the magnetron plasma. Operating the magnetron at constant power, it was observed that its discharge current is raised from 1.8 A to 4.8 A, when the ECR discharge was superimposed with a microwave power of 2 kW. At the same time, the discharge voltage decreased from about 560 V to 210 V, clearly indicating a higher plasma density of the MECRIS mode. The optical emission spectrum of the MECRIS plasma is dominated by lines of excited Al atoms and shows a significant contribution of lines arising from singly ionized Al. Plasma emission photography with a CCD camera was used to prove probe measurements and to identify separated plasma emission zones originating from the ECR and magnetron discharge.
Radiation effects in semiconductors: technologies for hardened integrated circuits
International Nuclear Information System (INIS)
Charlot, J.M.
1983-09-01
Various technologies are used to manufacture integrated circuits for electronic systems. But for specific applications, including those with radiation environment, it is necessary to choose an appropriate technologie or to improve a specific one in order to reach a definite hardening level. The aim of this paper is to present the main effects induced by radiation (neutrons and gamma rays) into the basic semiconductor devices, to explain some physical degradation mechanisms and to propose solutions for hardened integrated circuit fabrication. The analysis involves essentially the monolithic structure of the integrated circuits and the isolation technology of active elements. In conclusion, the advantages of EPIC and SOS technologies are described and the potentialities of new technologies (GaAs and SOI) are presented
Radiation effects in semiconductors: technologies for hardened integrated circuits
International Nuclear Information System (INIS)
Charlot, J.M.
1984-01-01
Various technologies are used to manufacture integrated circuits for electronic systems. But for specific applications, including those with radiation environment, it is necessary to choose an appropriate technology or to improve a specific one in order to reach a definite hardening level. The aim of this paper is to present the main effects induced by radiation (neutrons and gamma rays) into the basic semiconductor devices, to explain some physical degradation mechanisms and to propose solutions for hardened integrated circuit fabrication. The analysis involves essentially the monolithic structure of the integrated circuits and the isolation technology of active elements. In conclusion, the advantages of EPIC and SOS technologies are described and the potentialities of new technologies (GaAs and SOI) are presented. (author)
International Nuclear Information System (INIS)
Hwang, R.N.; Toppel, B.J.; Henryson, H. II.
1980-10-01
Motivated by a need for an economical yet rigorous tool which can address the computation of the structural material Doppler effect, an extremely efficient improved RABANL capability has been developed utilizing the fact that the Doppler broadened line shape functions become essentially identical to the natural line shape functions or Lorentzian limits beyond about 100 Doppler widths from the resonance energy, or when the natural width exceeds about 200 Doppler widths. The computational efficiency has been further enhanced by preprocessing or screening a significant number of selected resonances during library preparation into composition and temperature independent smooth background cross sections. The resonances which are suitable for such pre-processing are those which are either very broad or those which are very weak. The former contribute very little to the Doppler effect and their self-shielding effect can readily be averaged into slowly varying background cross section data, while the latter contribute very little to either the Doppler or to self-shielding effects. To illustrate the accuracy and efficiency of the improved RABANL algorithms and resonance screening techniques, calculations have been performed for two systems, the first with a composition typical of the STF converter region and the second typical of an LMFBR core composition. Excellent agreement has been found for RABANL compared to the reference Monte Carlo solution obtained using the code VIM, and improved results have also been obtained for the narrow resonance approximation in the ultra-fine-group option of MC 2 -2
Ogino, Kota; Suzuki, Safumi; Asada, Masahiro
2017-12-01
Spectral narrowing of a resonant-tunneling-diode (RTD) terahertz oscillator, which is useful for various applications of terahertz frequency range, such as an accurate gas spectroscopy, a frequency reference in various communication systems, etc., was achieved with a phase-locked loop system. The oscillator is composed of an RTD, a slot antenna, and a varactor diode for electrical frequency tuning. The output of the RTD oscillating at 610 GHz was down-converted to 400 MHz by a heterodyne detection. The phase noise was transformed to amplitude noise by a balanced mixer and fed back into the varactor diode. The loop filter for a stable operation is discussed. The spectral linewidth of 18.6 MHz in free-running operation was reduced to less than 1 Hz by the feedback.
International Nuclear Information System (INIS)
Soliman, N.F.
2012-01-01
In k 0 - Neutron Activation Analysis (k 0 -NAA), the conversion from the tabulated Q 0 (ratio of the resonance integral to thermal neutron cross-section)to Q 0 (α) (α is the shape factor of the epithermal neutron flux, indicating the deviation of the epithermal neutron spectrum from the ideal 1/E shape) are calculated using a FORTRAN program. The calculations are done for most elements that can be detected by neutron activation using different values of the parameter (α) ranging from -0.1≤α≤+0.1. The obtained data are used to study the dependence of the values (α) on the irradiation position factor in (k 0 -NAA)equation for some selected isotopes differ in their resonance energy and its Q 0 values. The results show that, the irradiation factor is affective mainly for low thermal tro epithermal flux ratio f especially for Q 0 value greater than 50. so consequently determining the irradiation parameters α value is not needed for irradiation positions that rich with thermal neutron. But for high f values the irradiation position factor should be taken into account. On the other hand the constructed FORTRAN program can be used to calculate the value Q 0 (α) directly for different value of α
International Nuclear Information System (INIS)
Yu, Haitao; Guo, Xinmeng; Wang, Jiang; Deng, Bin; Wei, Xile
2014-01-01
The phenomenon of stochastic resonance in Newman-Watts small-world neuronal networks is investigated when the strength of synaptic connections between neurons is adaptively adjusted by spike-time-dependent plasticity (STDP). It is shown that irrespective of the synaptic connectivity is fixed or adaptive, the phenomenon of stochastic resonance occurs. The efficiency of network stochastic resonance can be largely enhanced by STDP in the coupling process. Particularly, the resonance for adaptive coupling can reach a much larger value than that for fixed one when the noise intensity is small or intermediate. STDP with dominant depression and small temporal window ratio is more efficient for the transmission of weak external signal in small-world neuronal networks. In addition, we demonstrate that the effect of stochastic resonance can be further improved via fine-tuning of the average coupling strength of the adaptive network. Furthermore, the small-world topology can significantly affect stochastic resonance of excitable neuronal networks. It is found that there exists an optimal probability of adding links by which the noise-induced transmission of weak periodic signal peaks
Energy Technology Data Exchange (ETDEWEB)
Yu, Haitao; Guo, Xinmeng; Wang, Jiang, E-mail: jiangwang@tju.edu.cn; Deng, Bin; Wei, Xile [School of Electrical Engineering and Automation, Tianjin University, Tianjin 300072 (China)
2014-09-01
The phenomenon of stochastic resonance in Newman-Watts small-world neuronal networks is investigated when the strength of synaptic connections between neurons is adaptively adjusted by spike-time-dependent plasticity (STDP). It is shown that irrespective of the synaptic connectivity is fixed or adaptive, the phenomenon of stochastic resonance occurs. The efficiency of network stochastic resonance can be largely enhanced by STDP in the coupling process. Particularly, the resonance for adaptive coupling can reach a much larger value than that for fixed one when the noise intensity is small or intermediate. STDP with dominant depression and small temporal window ratio is more efficient for the transmission of weak external signal in small-world neuronal networks. In addition, we demonstrate that the effect of stochastic resonance can be further improved via fine-tuning of the average coupling strength of the adaptive network. Furthermore, the small-world topology can significantly affect stochastic resonance of excitable neuronal networks. It is found that there exists an optimal probability of adding links by which the noise-induced transmission of weak periodic signal peaks.
Resonance phase and sings of P-odd and P-even effects, observable in the reactions with neutrons
International Nuclear Information System (INIS)
Smotritskij, L.M.
2002-01-01
It is shown that introduction of the resonance phase for two quasistationary states with a similar spin and counter parity makes it possible to correlate the sing dependence of both the P-odd and P-even effects, experimentally observed in the reactions with neutrons. The common description of such effects enables determination of the theory unknown (free) parameters from the experiment [ru
Enflo, Laura; Sundberg, Johan; Romedahl, Camilla; McAllister, Anita
2013-01-01
Purpose: Resonance tube phonation in water (RTPW) or in air is a voice therapy method successfully used for treatment of several voice pathologies. Its effect on the voice has not been thoroughly studied. This investigation analyzes the effects of RTPW on collision and phonation threshold pressures (CTP and PTP), the lowest subglottal pressure…
Neutron Activation Resonance Integrals of 64Zn, 68Zn, 85Rb, 100Mo, 102Ru, 113In, 123Sb, and 180Hf
International Nuclear Information System (INIS)
Ricabarra, M. D.; Turjanski, R.; Ricabarra, G. H.
1969-01-01
The ratio of resonance integral to thermal activation cross sections of the isotopes 64 Zn, 68 Zn, 85 Rb, 100 Mo, 102 Ru, 113 In, 123 Sb, and 180 Hf relative to gold has been determined by measuring cadmium ratios. The standard gold or a secondary standard was mixed uniformly in the samples and the activities resolved with a lithium-drift germanium γ-ray spectrometer. Expressed as Westcott S 0 values the results were: 64 Zn = 2.06 ± 0.03, 68 Zn = 3.72 ± 0.14, 85 Rb = 18.4 ± 0.6, 100 Mo = 21.7 ± 0.8, 102 Ru = 3.76 ± 0.03, 113 In = 24.7 ± 0.5, 123 Sb = 28.3 ± 2.1, 180 Hf = 2.17 ± 0.09. All measurements are relative to S 0 = 17.7 for gold. (author)
Memory effects on a resonate-and-fire neuron model subjected to Ornstein-Uhlenbeck noise
Paekivi, S.; Mankin, R.; Rekker, A.
2017-10-01
We consider a generalized Langevin equation with an exponentially decaying memory kernel as a model for the firing process of a resonate-and-fire neuron. The effect of temporally correlated random neuronal input is modeled as Ornstein-Uhlenbeck noise. In the noise-induced spiking regime of the neuron, we derive exact analytical formulas for the dependence of some statistical characteristics of the output spike train, such as the probability distribution of the interspike intervals (ISIs) and the survival probability, on the parameters of the input stimulus. Particularly, on the basis of these exact expressions, we have established sufficient conditions for the occurrence of memory-time-induced transitions between unimodal and multimodal structures of the ISI density and a critical damping coefficient which marks a dynamical transition in the behavior of the system.
International Nuclear Information System (INIS)
Kim, Yonghee; Heo, Myoung-Sun; Moon, Geol; Kim, Ji-Hyoun; Jhe, Wonho; Noh, Heung-Ryoul
2010-01-01
We experimentally demonstrate resonant symmetry lifting in a parametrically modulated magneto-optical trap of cold 85 Rb atoms. This is achieved by applying a weak additional modulation at half the frequency of the strong parametric modulation, which acts as an effective static bias field to the system. We measure the system response by varying the amplitude of the additional fictitious bias as well as the relative phase between the bias and the parametric drive, and the results are in good agreement with theory. The additional modulation provides an additional degree of freedom to control the system, which is useful for investigating system properties such as susceptibility, dynamic response, and related critical phenomena. We also have measured the amplitude of the response to higher harmonics of the additional modulation frequency, which allows more precise understanding of the system dynamics.
Effects of resonant magnetic perturbation on the triggering and the evolution of double-tearing mode
Wang, L.; Lin, W. B.; Wang, X. Q.
2018-02-01
The effects of resonant magnetic perturbation on the triggering and the evolution of the double-tearing mode are investigated by using nonlinear magnetohydrodynamics simulations in a slab geometry. It is found that the double-tearing mode can be destabilized by boundary magnetic perturbation. Moreover, the mode has three typical development stages before it reaches saturation: the linear stable stage, the linear-growth stage, and the exponential-growth stage. The onset and growth of the double-tearing mode significantly depend on the boundary magnetic perturbations, particularly in the early development stage of the mode. The influences of the magnetic perturbation amplitude on the mode for different separations of the two rational surfaces are also discussed.
Substitution effect in nuclear magnetic resonance of C-13: α methoxicyclohexanones
International Nuclear Information System (INIS)
Lopez Holland, M.A.G.
1984-01-01
Eletronic and steric interactions between the carbonyl and methoxyl groups in α-methoxicyclohexanones by H-1 and C-13 nuclear magnetic resonance spectroscopy (n.m.r) is studied. Interpretation of H-1 n.m.r measurements based on the carbonyl group anisotropy is made. The asigment of spectral lines to specific nuclear by Lanthanide Shift Reagent Experiments is confirmed. Interpretation of C-13 n.m.r. spectra with respect to molecular effects and emphirical relationships associated with the substituent was analysed. The C-13 chemical shift asignment by comparison with results of partially (SFORD) and fully decompled spectra and also by relating the measured chemical shift with values cited in the literature for similar compounds are made. A qualitative study using I.R. spectroscopy in attempt to evaluate the predominance of one the conformers of the studied compounds in solutions of n-hexan and chloroform is made. (M.J.C.) [pt
International Nuclear Information System (INIS)
Chu, Viet Ha; Nghiem, Thi Ha Lien; Tran, Hong Nhung; Fort, Emmanuel
2011-01-01
Due to the energy transfer from surface plasmons, the fluorescence of fluorophores near metallic nanostructures can be enhanced. This effect has been intensively studied recently for biosensor applications. This work reports on the luminescence enhancement of 100 nm Cy3 dye-doped polystyrene nanoparticles by energy transfer from surface plasmons of gold colloidal nanoparticles with sizes of 20 and 100 nm. Optimal luminescence enhancement of the fluorophores has been observed in the mixture with 20 nm gold nanoparticles. This can be attributed to the resonance energy transfer from gold nanoparticles to the fluorophore beads. The interaction between the fluorophores and gold particles is attributed to far-field interaction
International Nuclear Information System (INIS)
Ursu, I.; Demco, D.E.; Simplaceanu, V.; Valcu, N.
1977-01-01
The nuclear magnetic resonance method is able to provide information concerning the isotopic content of 235 U in UF 6 by means of measuring the nuclear magnetic transverse relaxation time (T,L2) of 19 F nuclei in liquid UF 6 . In this work, the sources of errors in the T 2 measurements have been analysed and methods for reducing them are dicussed. Typical errors in T 2 determinations are below 2%. The enrichment estimations made by using the linear calibration curves had a deviation of less than 2% with some exceptions. It was found that the chemical impurities may significantly affect the enrichment estimations. 19 F NMR spectra of liquid and gaseous UF 6 at low pressures did not reveal any structure or enrichment effect. The longitudinal nuclear magnetic relaxation of 19 F nuclei in low pressure, gaseous and solid UF 6 showed no enrichment dependence, nor the dipolar relaxation time in solid UF 6 did. (author)
The state of development of an intense resonance electron-ion accelerator based on Doppler effect
International Nuclear Information System (INIS)
Egorov, A.M.; Ivanov, B.I.; Butenko, V.I.; Ognivenko, V.V.; Onishchenko, I.N.; Prishchepov, V.P.
1996-01-01
An intense ion accelerator has been proposed and now is being developed in which accelerating and focusing electric fields in a slow wave structure are excited by an intense electron beam using the anomalous and the normal Doppler effects. The results of theoretical studies and computer simulations show the advantage of this acceleration method that will make it possible to obtain acceleration rates of the order of 10 - 100 MeV/m, and ion beam energies and currents of the order of 10-100 MeV, 1-10 A. The project and technical documentation of an experimental accelerating installation were worked out. Currently, the 5 MeV accelerator-injector URAL-5 is in operation; preliminary experiments on a small installation have been carried out; experimental investigations of an accelerating RF resonator model (in 1/2 scaling) are being performed; the accelerating test installation is being manufactured. (author). 1 tab. 12 fig., 6 refs
Excellent polarization-independent reflector based on guided mode resonance effect
International Nuclear Information System (INIS)
Xu Cheng; Xu Lin-Min; Qiang Ying-Huai; Zhu Ya-Bo; Liu Jiong-Tian; Ma Jian-Yong
2011-01-01
A broad band polarization-independent reflector working in the telecommunication C+L band is proposed using the guided mode resonance effect of a periodic surface relief element deposited by a layer of silicon medium. It is shown that this structure can provide high reflection (R > 99.5%) and wide angular bandwidth (θ ≈ 20°, R > 98%) for both TE and TM polarizations over a wide spectrum band 1.5 μm∼1.6 μm. Furthermore, it is found by rigorous coupled wave analysis that the polarization-independent reflector proposed here is tolerant of a deviation of grating thickness, which makes it very easy to fabricate in experiments. (electromagnetism, optics, acoustics, heat transfer, classical mechanics, and fluid dynamics)
The state of development of an intense resonance electron-ion accelerator based on Doppler effect
Energy Technology Data Exchange (ETDEWEB)
Egorov, A M; Ivanov, B I; Butenko, V I; Ognivenko, V V; Onishchenko, I N; Prishchepov, V P [Kharkov Inst. of Physics and Technology (Ukraine)
1997-12-31
An intense ion accelerator has been proposed and now is being developed in which accelerating and focusing electric fields in a slow wave structure are excited by an intense electron beam using the anomalous and the normal Doppler effects. The results of theoretical studies and computer simulations show the advantage of this acceleration method that will make it possible to obtain acceleration rates of the order of 10 - 100 MeV/m, and ion beam energies and currents of the order of 10-100 MeV, 1-10 A. The project and technical documentation of an experimental accelerating installation were worked out. Currently, the 5 MeV accelerator-injector URAL-5 is in operation; preliminary experiments on a small installation have been carried out; experimental investigations of an accelerating RF resonator model (in 1/2 scaling) are being performed; the accelerating test installation is being manufactured. (author). 1 tab. 12 fig., 6 refs.
International Nuclear Information System (INIS)
Payne, M.G.; Deng, L.; Garrett, W.R.
1998-01-01
We present a theory for two- and three-photon excitation, optical shifting, and four-wave mixing when a first laser is tuned onto, or near, a two-photon resonance and a second much more intense laser is tuned near or on resonance between the two-photon resonance and a second excited state. When the second excited state has a dipole-allowed transition back to the ground state and the concentration is sufficiently high, a destructive interference is produced between three-photon coupling of the ground state and the second excited state and one-photon coupling between the same states by the internally generated four-wave mixing field. This interference leads to several striking effects. For instance, as the onset of the interference occurs, the optical shifts in the two-photon resonance excitation line shape become smaller in copropagating geometry so that the line shapes for multiphoton ionization enhanced by the two-photon resonance eventually become unaffected by the second laser. In the same range of concentrations the four-wave mixing field evolves to a concentration-independent intensity. With counterpropagating laser beams the line shape exhibits normal optical shifts like those observed for both copropagating and counterpropagating laser beams at very low concentrations. The theoretical work presented here extends our earlier works by including the effect of laser bandwidth and by removing the restriction of having the second laser be tuned far from three-photon resonance. In this way we have now included, as a special case, the effect of both laser bandwidth and interference on laser-induced transparency. Unlike other effects related to odd-photon destructive interference, the effect of a broad bandwidth is to bring about the predicted effects at much lower concentrations. Studies in rubidium show good agreement between theory and experiment for both ionization line shapes and four-wave mixing intensity as a function of concentration. copyright 1998 The
Antiproton-nucleus interaction and nuclear E2 resonance effect in molybdenum and neodymium isotopes
International Nuclear Information System (INIS)
Kanert, W.
1986-01-01
Antiprotonix X-radiation from 92 Mo, 94 Mo, 95 Mo, 98 Mo, 100 Mo and 146 Nd, 148 Nd was measured with Ge detectors at the LEAR (CERN). The nuclear E2 resonance effect (configuration mixing by dynamic electric quadrupole interaction) was for the first time observed in antiprotonic atoms. It effects in 94 Mo, 95 Mo, and 98 Mo a mixing of the atomic levels (7,6) and (5,4). From the resulting weakening of the antiprotonic X-ray line (7→6) in comparison with the nonresonant isotope 92 Mo information on the effects of the strong interaction in the (5,4) level was obtained which is in Mo not directly observable. The absorption widths by strong interactions in the level (6,5) resulted for 92 Mo, 94 Mo, 95 Mo, and 98 Mo to 1.4±0.3 keV, 2.3±0.9 keV, 1.9±0.4 keV, and 2.3±0.7 keV, the energy shifts by strong interactions to 0.46±0.08 keV, 0.64±0.22 keV, 0.74±0.12 keV, and 0.55±0.16 keV. In the nonresonant isotope 92 Mo the absorption width of the level (7,6) to 19.5±1.2 eV. A fit of the effective scattering length to the data for 92 Mo resulted anti a = (0.25+3.05i) fm. In 100 Mo the predicted case of strong coupling could be experimentally established by the nearly complete extinction of the line (8→7) and the broadening of the line (9→8). In 148 Nd the nuclear E2 resonance effect effects a mixing of the levels (9,8) and (8,6) and by this a reduction of the line (9→8) in comparison to 146 Nd. For this isotope information on the effects of the strong interaction could be extracted separately for the fine structure components. (orig.) [de
Tavakol, Parvin; Labruto, Fausto; Bergstrand, Lott; Blomqvist, Lennart
2011-02-01
Sometimes the measures taken to make a radiology department more effective, such as prioritizing the workload and keeping equipment running for as many hours as staffing permits, are not enough. In such cases, outsourcing radiological examinations is a potential solution for reducing waiting times. To investigate differences in waiting time, quality and costs between magnetic resonance (MR) examinations performed in a university hospital and examinations outsourced to private service. We retrospectively selected a group of consecutive, outsourced MR examinations (n=97) and a control group of in-house MR examinations, matched for type of examination. In each group there were referrals that had a specified preferred timeframe for completion. We measured the percentage of cases in which this timeframe was met and if it was not met, how many days exceeded the preferred time. In referrals without a specified preferred timeframe, we also calculated the waiting time. Quality standards were measured by the percentage of examinations that had to be re-done and re-assessed. Finally, we calculated the cumulative costs, taking into account the costs for re-doing and re-assessing examinations. There was no statistically significant difference between the groups, in either the number of examinations that were not performed within the preferred time or the number of days that exceeded the preferred timeframe. For referrals without a preferred timeframe, the waiting time was shorter for outsourced examinations than those not outsourced. There were no differences in the number of examinations that had to be re-done, but more examinations needed to be re-assessed in the outsourced group than in the in-house group. The calculated costs for outsourced examinations were lower than the costs for internally performed examinations. Outsourcing magnetic resonance examinations may be an effective way of reducing a radiology department's workload. Ways in which to reduce the additional costs
Thermal and rotational effect on giant dipole resonances in rotating nuclei at high temperature
International Nuclear Information System (INIS)
Sugawara-Tanabe, Kazuko; Tanabe, Kosai.
1986-01-01
Microscopic calculations are carried out for the giant dipole resonances excited on the thermal high spin states in 162 Er and 166 Er based on the thermal linear response theory with realistic forces and large single-particle space. The dynamical strength function is compared with the experimental γ-ray absorption cross section. The general trend that the resonance energy decreases and the resonance width increases with increasing angular momentum and temperature is well reproduced by the calculations. (author)
Thermal Hydraulic Integral Effect Tests for Pressurized Water Reactors
International Nuclear Information System (INIS)
Baek, Won Pil; Song, C. H.; Kim, Y. S.
2007-02-01
The objectives of the project are to construct a thermal-hydraulic integral effect test facility and to perform the tests for design, operation, and safety regulation of pressurized water reactors. In the first phase of this project (1997.8∼2002.3), the basic technology for thermal-hydraulic integral effect tests was established and the basic design of the test facility was accomplished. In the second phase (2002.4∼2005.2), an optimized design of the ATLAS (Advanced Thermal-hydraulic Test Loop for Accident Simulation) was established and the construction of the facility was almost completed. In the third phase (2005.3∼2007.2), the construction and commission tests of the ATLAS are to be completed and some first-phase tests are to be conducted
Ravi, Keerthi Sravan; Potdar, Sneha; Poojar, Pavan; Reddy, Ashok Kumar; Kroboth, Stefan; Nielsen, Jon-Fredrik; Zaitsev, Maxim; Venkatesan, Ramesh; Geethanath, Sairam
2018-03-11
To provide a single open-source platform for comprehensive MR algorithm development inclusive of simulations, pulse sequence design and deployment, reconstruction, and image analysis. We integrated the "Pulseq" platform for vendor-independent pulse programming with Graphical Programming Interface (GPI), a scientific development environment based on Python. Our integrated platform, Pulseq-GPI, permits sequences to be defined visually and exported to the Pulseq file format for execution on an MR scanner. For comparison, Pulseq files using either MATLAB only ("MATLAB-Pulseq") or Python only ("Python-Pulseq") were generated. We demonstrated three fundamental sequences on a 1.5 T scanner. Execution times of the three variants of implementation were compared on two operating systems. In vitro phantom images indicate equivalence with the vendor supplied implementations and MATLAB-Pulseq. The examples demonstrated in this work illustrate the unifying capability of Pulseq-GPI. The execution times of all the three implementations were fast (a few seconds). The software is capable of user-interface based development and/or command line programming. The tool demonstrated here, Pulseq-GPI, integrates the open-source simulation, reconstruction and analysis capabilities of GPI Lab with the pulse sequence design and deployment features of Pulseq. Current and future work includes providing an ISMRMRD interface and incorporating Specific Absorption Ratio and Peripheral Nerve Stimulation computations. Copyright © 2018 Elsevier Inc. All rights reserved.
Heuberer, Philipp R; Smolen, Daniel; Pauzenberger, Leo; Plachel, Fabian; Salem, Sylvia; Laky, Brenda; Kriegleder, Bernhard; Anderl, Werner
2017-05-01
The number of arthroscopic rotator cuff surgeries is consistently increasing. Although generally considered successful, the reported number of retears after rotator cuff repair is substantial. Short-term clinical outcomes are reported to be rarely impaired by tendon retears, whereas to our knowledge, there is no study documenting long-term clinical outcomes and tendon integrity after arthroscopic rotator cuff repair. To investigate longitudinal long-term repair integrity and clinical outcomes after arthroscopic rotator cuff reconstruction. Case series; Level of evidence, 4. Thirty patients who underwent arthroscopic rotator cuff repair with suture anchors for a full-tendon full-thickness tear of the supraspinatus or a partial-tendon full-thickness tear of the infraspinatus were included. Two and 10 years after initial arthroscopic surgery, tendon integrity was analyzed using magnetic resonance imaging (MRI). The University of California, Los Angeles (UCLA) score and Constant score as well as subjective questions regarding satisfaction with the procedure and return to normal activity were used to evaluate short- and long-term outcomes. At the early MRI follow-up, 42% of patients showed a full-thickness rerupture, while 25% had a partial rerupture, and 33% of tendons remained intact. The 10-year MRI follow-up (129 ± 11 months) showed 50% with a total rerupture, while the other half of the tendons were partially reruptured (25%) or intact (25%). The UCLA and Constant scores significantly improved from preoperatively (UCLA total: 50.6% ± 20.2%; Constant total: 44.7 ± 10.5 points) to 2 years (UCLA total: 91.4% ± 16.0% [ P rotator cuff repair showed good clinical long-term results despite a high rate of retears. Nonetheless, intact tendons provided significantly superior clinical long-term outcomes, making the improvement of tendon healing and repair integrity important goals of future research efforts.
Integrating Individual-Based Indices of Contaminant Effects
Directory of Open Access Journals (Sweden)
Christopher L. Rowe
2001-01-01
Full Text Available Habitat contamination can alter numerous biological processes in individual organisms. Examining multiple individual-level responses in an integrative fashion is necessary to understand how individual health or fitness reflects environmental contamination. Here we provide an example of such an integrated perspective based upon recent studies of an amphibian (the bullfrog, Rana catesbeiana that experiences several, disparate changes when larval development occurs in a trace element�contaminated habitat. First, we present an overview of studies focused on specific responses of individuals collected from, or transplanted into, a habitat contaminated by coal combustion residues (CCR. These studies have reported morphological, behavioral, and physiological modifications to individuals chronically interacting with sediments in the CCR-contaminated site. Morphological abnormalities in the oral and tail regions in contaminant-exposed individuals influenced other properties such as grazing, growth, and swimming performance. Behavioral changes in swimming activities and responses to stimuli appear to influence predation risk in the contaminant-exposed population. Significant changes in bioenergetics in the contaminated habitat, evident as abnormally high energetic expenditures for survival (maintenance costs, may ultimately influence production pathways (growth, energy storage in individuals. We then present a conceptual model to examine how interactions among the affected systems (morphological, behavioral, physiological may ultimately bring about more severe effects than would be predicted if the responses were considered in isolation. A complex interplay among simultaneously occurring biological changes emerges in which multiple, sublethal effects ultimately can translate into reductions in larval or juvenile survival, and thus reduced recruitment of juveniles into the population. In systems where individuals are exposed to low concentrations of
Optimal transformation for correcting partial volume averaging effects in magnetic resonance imaging
International Nuclear Information System (INIS)
Soltanian-Zadeh, H.; Windham, J.P.; Yagle, A.E.
1993-01-01
Segmentation of a feature of interest while correcting for partial volume averaging effects is a major tool for identification of hidden abnormalities, fast and accurate volume calculation, and three-dimensional visualization in the field of magnetic resonance imaging (MRI). The authors present the optimal transformation for simultaneous segmentation of a desired feature and correction of partial volume averaging effects, while maximizing the signal-to-noise ratio (SNR) of the desired feature. It is proved that correction of partial volume averaging effects requires the removal of the interfering features from the scene. It is also proved that correction of partial volume averaging effects can be achieved merely by a linear transformation. It is finally shown that the optimal transformation matrix is easily obtained using the Gram-Schmidt orthogonalization procedure, which is numerically stable. Applications of the technique to MRI simulation, phantom, and brain images are shown. They show that in all cases the desired feature is segmented from the interfering features and partial volume information is visualized in the resulting transformed images
Farhat, Mohamed
2014-08-01
We present in this paper a theoretical and numerical analysis of bending waves localized on the boundary of a platonic crystal whose building blocks are Split Ring Resonators (SRR). We first derive the homogenized parameters of the structured plate using a three-scale asymptotic expansion in the linearized biharmonic equation. In the limit when the wavelength of the bending wave is much larger than the typical heterogeneity size of the platonic crystal, we show that it behaves as an artificial plate with an anisotropic effective Young modulus and a dispersive effective mass density. We then analyze dispersion diagrams associated with bending waves propagating within an infinite array of SRR, for which eigen-solutions are sought in the form of Floquet-Bloch waves. We finally demonstrate that this structure displays the hallmarks of All-Angle Negative Refraction (AANR) and it leads to superlensing and ultrarefraction effects, interpreted thanks to our homogenization model as a consequence of negative and vanishing effective density, respectively. © EPLA, 2014.
Farhat, Mohamed; Enoch, Stefan; Guenneau, Sé bastien
2014-01-01
We present in this paper a theoretical and numerical analysis of bending waves localized on the boundary of a platonic crystal whose building blocks are Split Ring Resonators (SRR). We first derive the homogenized parameters of the structured plate using a three-scale asymptotic expansion in the linearized biharmonic equation. In the limit when the wavelength of the bending wave is much larger than the typical heterogeneity size of the platonic crystal, we show that it behaves as an artificial plate with an anisotropic effective Young modulus and a dispersive effective mass density. We then analyze dispersion diagrams associated with bending waves propagating within an infinite array of SRR, for which eigen-solutions are sought in the form of Floquet-Bloch waves. We finally demonstrate that this structure displays the hallmarks of All-Angle Negative Refraction (AANR) and it leads to superlensing and ultrarefraction effects, interpreted thanks to our homogenization model as a consequence of negative and vanishing effective density, respectively. © EPLA, 2014.
Major Achievements and Prospect of the ATLAS Integral Effect Tests
International Nuclear Information System (INIS)
Choi, K.; Kim, Y.; Song, C.; Baek, W.
2012-01-01
A large-scale thermal-hydraulic integral effect test facility, ATLAS (Advanced Thermal-hydraulic Test Loop for Accident Simulation), has been operated by KAERI. The reference plant of ATLAS is the APR1400 (Advanced Power Reactor, 1400 MWe). Since 2007, an extensive series of experimental works were successfully carried out, including large break loss of coolant accident tests, small break loss of coolant accident tests at various break locations, steam generator tube rupture tests, feed line break tests, and steam line break tests. These tests contributed toward an understanding of the unique thermal-hydraulic behavior, resolving the safety-related concerns and providing validation data for evaluation of the safety analysis codes and methodology for the advanced pressurized water reactor, APR1400. Major discoveries and lessons found in the past integral effect tests are summarized in this paper. As the demand for integral effect tests is on the rise due to the active national nuclear R and D program in Korea, the future prospects of the application of the ATLAS facility are also discussed.
Nuclear magnetic resonance studies of quadrupolar nuclei and dipolar field effects
International Nuclear Information System (INIS)
Urban, Jeffry Todd
2004-01-01
Experimental and theoretical research conducted in two areas in the field of nuclear magnetic resonance (NMR) spectroscopy is presented: (1) studies of the coherent quantum-mechanical control of the angular momentum dynamics of quadrupolar (spin I > 1/2) nuclei and its application to the determination of molecular structure; and (2) applications of the long-range nuclear dipolar field to novel NMR detection methodologies.The dissertation is organized into six chapters. The first two chapters and associated appendices are intended to be pedagogical and include an introduction to the quantum mechanical theory of pulsed NMR spectroscopy and the time dependent theory of quantum mechanics. The third chapter describes investigations of the solid-state multiple-quantum magic angle spinning (MQMAS) NMR experiment applied to I 5/2 quadrupolar nuclei. This work reports the use of rotary resonance-matched radiofrequency irradiation for sensitivity enhancement of the I = 5/2 MQMAS experiment. These experiments exhibited certain selective line narrowing effects which were investigated theoretically.The fourth chapter extends the discussion of multiple quantum spectroscopy of quadrupolar nuclei to a mostly theoretical study of the feasibility of enhancing the resolution of nitrogen-14 NMR of large biomolecules in solution via double-quantum spectroscopy. The fifth chapter continues to extend the principles of multiple quantum NMR spectroscopy of quadrupolar nuclei to make analogies between experiments in NMR/nuclear quadrupolar resonance (NQR) and experiments in atomic/molecular optics (AMO). These analogies are made through the Hamiltonian and density operator formalism of angular momentum dynamics in the presence of electric and magnetic fields.The sixth chapter investigates the use of the macroscopic nuclear dipolar field to encode the NMR spectrum of an analyte nucleus indirectly in the magnetization of a sensor nucleus. This technique could potentially serve as an encoding