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A two-dimensional computational fluid dynamics (CFD) numerical model is developed to study the power takeoff (PTO) efficiency of an Edinburgh duck wave energy converter (WEC) device by using the OpenFOAM source package. After the numerical validations and the convergent verifications, the characteristics of the duck WEC device for the power takeoff in various incident wave periods are examined. The present numerical investigation indicates that the maximum absorbed power of the duck WEC device is attained in its resonant period, while the maximum efficiency is achieved in a lower period. The influence of the damping coefficient on the PTO is also investigated. The optimal damping coefficient for acquiring more power and better efficiency is determined from a numerical examination.

A Tm:YAP laser with an output wavelength of 1989 nm was selected for the first time as the pump source of a Q-switched Ho:YAP laser. When the absorbed power was 30 W, an average power of 18.02 W with the pulse width of 104.2 ns acousto-optic (AO) Q-switched Ho:YAP laser was obtained at a repetition frequency of 10 kHz. The slope efficiency was 70.11%, and the optical-optical conversion efficiency was 43.03%. The output center wavelength was 2129.22 nm with the line width of 0.74 nm.

A few-layer tungsten disulfide (WS2) nanosheet film on a YAG substrate was fabricated and used as saturable absorber in a passively Q-switched Er:SrF2 laser operating at 2.79 µm. Under an absorbed power of 2.42 W, a stable Q-switched laser operation was realized with an average output power of 428 mW and a pulse duration of 679 ns at a repetition rate of 38 kHz, corresponding to a pulse energy of 11.26 µJ.

Transport calculations of the operational regimes for the constructed modified T-15 device are presented. The Canonical Profiles Transport Model (CPTM), verified with JET and MAST tokamaks, is used in the simplified version: Te, Ti and current density diffusion equations are solved with the fixed plasma density n profile. L- and H- modes are described by the appropriate modeling of the boundary conditions for the temperatures and plasma density, confirmed by JET experiment. The absorbed power density profile is determined by the simple formulas. The results are presented as graphics and tables, which can be easily used in order to cre ate the scientific device programs, to develop diagnostics or to define the position of the device in modern tokamak experiments.

A diode-pumped 937 nm Nd:GGG laser operating on the quasi-three-level under direct pumping at wavelength of around 882 nm is demonstrated, and its performances are investigated. A maximum output power of 358 mW at 937 nm was achieved at absorbed pump power of 4.8 W. The optical-to-optical conversion efficiency and the slope efficiency relative to absorbed power were 7.5 and 11.2%, respectively.

Conducting composites of polyaniline doped with dodecylbenzenesulfonic acid (PAni-DBSA) and poly(styrene-b-styrene-butadiene-b-styrene) (STF) as supporting matrix were prepared by in situ synthesis. The influence of composition and thickness on the electromagnetic properties and shielding effectiveness (SE) of the materials was evaluated using a microwave network analyzer and a standard rectangular waveguide from 8.2–12.4 GHz (X–band). It was found that the composition 49/51 exhibited the best SE and the higher values of reflected power (PR), e′, e″ and e*. The compositions 12/88 and 17/83 presented the higher values of transmitted power (PT) and absorbed power (PA), respectively. The composition 25/75 presented the higher value of tan δ. The thickness of 5× showed the best SE and higher value of PR. The higher value of transmitted power (PT) was obtained for thickness of 1×. The values of PA were similar for all thicknesses. The thickness of 1x showed the higher values of e′, e″, e* and tan δ.

This study investigated the significance of blood vessels in the absorbed power and temperature distributions when optimization was employed during hyperthermia. The treated tumor region was simulated using a three-dimensional (3D) tissue model embedded with a countercurrent blood vessel network (Huang et al., 1996). 3D temperature distributions are obtained by solving the conduction equation in the tissues and the convective energy equation with specified Nusselt number in the vessels. 3D absorbed power depositions are obtained by using optimization to reach a uniform temperature of 43 °C for the desired treated region. Results show that the absorbed power deposition for optimization with fine spatial resolution produces a uniform temperature distribution maintained at 43 °C in the desired treated tumor region except for some cold spots and/or small cold strips caused by thermally significant large vessels. The amount of total absorbed power suggests that a region with thermally significant vasculature requires much more power deposited than one without vasculature. In addition, optimization with coarse spatial resolution results in a highly inhomogeneous temperature distribution in the treated region due to the strong cooling effect of blood vessels. Therefore, prior to hyperthermia treatments, thermally significant blood vessels should be identified and handled carefully to effectively reduce their strong cooling effect, particularly those vessels flowing into the treated region.

In the condition of certain electromagnetic levitation coi l and spherical sample, according to the expressions of levitation force and absorbed power in magnetic field, the re lationship between levitation force, absorbed power and high frequency power supply frequency is established in this paper. In addition, the effect of the power supply frequency on the levitation force of the coil and the absorbed power of the sample is analyzed, and the general rules of frequency parameter selection are confirmed. Finally, a guiding role in the frequ ency selection of high frequency power supply in electromagnetic levitation melting is played.

Three dimensional plasma simulation is presented and the results are compared with the experimental observations by Langmuir probe for an industrial inductively coupled plasma (ICP) reactor employing multi-spiral coils. In this simulation, gas heating is also taken into consideration since the gas density is inversely proportional to temperature and the effect is not negligible. It is shown that the gas temperature near the susceptor reach at 400K while the chamber is kept at 300 K when the absorbed power of the electron is at 1.5 kW. The elapsed time for one run is about only 85 minutes for Ar and it is quite acceptable as an industrial tool for various plasma processes.

Infrared camera images are used to calculate the power deposited on a target by a millimeter wave source. Thin carbon-impregnated sheets of Kapton are illuminated with RF energy, and then infrared images in the 3-5 /spl mu/m band provide temperature data that is used to numerically solve the heat equation and obtain absorbed power values. Techniques to determine the electrical properties of Kapton up to 94 GHz were developed.

We present a new technique to analyze the absorption efficiency of the active medium for a LD side-pumped Nd:YAG laser. A detailed ray trace has been carried out to evaluate the route of the pump LD-rays propagating inside the diffusing chamber. The method, named the infinite convergence approach, is used to determine the total absorbed power of a Nd:YAG rod when random reflection takes place at the inner surface of the reflector wall. By reason of losses caused by slits milled the reflector wall, there is an optimum slit width corresponding to the maximum absorption efficiency. It has been theoretically determined that the absorption efficiency can be summarized by a convergent result for the infinite energy transfer process inside the diffusing chamber. The method is applicable to the cavity design for any LD side-pumped solid-state lasers.

Exposure to mechanical shocks might pose a greater health risk than exposure to continuous vibration. Previous studies have investigated subjective responses, muscle activity or transmission of vibration to the spine or head during shock. If there is a difference between biomechanic responses of the seated body to shocks when compared to continuous vibration, then this may indicate a more, or less, hazardous vibration waveform. This paper presents measurements of apparent mass and absorbed power during exposure to random vibration, repeated shocks and combinations of shocks and random vibration. Eleven male and 13 female subjects were exposed to 15 vibration conditions generated using an electro-dynamic shaker. Subjects were exposed to five 20 s acceleration waveforms with nominally identical power spectra (random vibration, equally spaced shocks, unequally spaced shocks, random combined with equally spaced shocks, random combined with unequally spaced shocks) at each of 0·5, 1·0 and 1·5 m/s2r.m.s. The general shapes of the apparent mass or absorbed power curves were not affected by stimulus type, indicating that the biomechanical response of the body is fundamentally the same when exposed to shocks or random vibration. Two non-linear effects were observed: apparent mass resonance frequencies were slightly higher for exposure to shocks; apparent mass and absorbed power resonance frequencies decreased with increases in vibration magnitude for each stimulus type. It is concluded that the two non-linear mechanisms operate simultaneously: a stiffening effect during exposure to shocks and a softening effect as vibration magnitudes increase. Total absorbed powers were greatest for shock stimuli and least for random vibration.

Evaluation of human exposure whole-body vibration (WBV) and shock can be carried out in a variety of ways. The most commonly used standards for predicting discomfort from WBV are BS6841 (1987) and ISO2631-1 (1997) which offer different frequency weightings ( W b and W k ) and three methods of assessment: vibration dose value (VDV), estimated VDV (eVDV) and maximum transient vibration value (MTVV). Previous studies have also used DRI and absorbed power for assessments of shock and WBV. This paper reports a laboratory study in which 24 human subjects were exposed to 15 vertical vibration stimuli comprising of random vibration, repeated shocks and combinations of random vibration and shocks at 0·5, 1·0 and 1·5 m/s 2 r.m.s. Subjects rated the discomfort from the vibration on a numerical scale after each exposure. Acquired acceleration signals were analyzed using VDV, r.m.s. and MTVV for unweighted, W b , W k and DRI weighted signals. Acceleration and force were combined to give a measure of absorbed power. Subjective responses were correlated to vibration magnitude for the 13 analysis types. VDV was the best standard method of assessment; MTVV was the worst. W b and W k frequency weightings showed slightly greater correlations between vibration magnitude and discomfort than DRI weighted or unweighted signals. For VDV, there were no significant differences between the correlations obtained using any frequency weighting. For assessment of all stimuli types together, absorbed power gave higher correlations with subjective discomfort than acceleration-based methods. It is concluded that the methods described in ISO2631-1 should be clarified and simplified. Due to the difficulty in measuring absorbed power in the field, methods proposed in BS6841 are recommended as the most appropriate for assessment of discomfort from continuous vibration or repeated shocks.

Cryogenic temperature operation of a 〈010〉-cut microchip Tm,Ho:Lu2SiO5 laser end-pumping by a fiber-coupled laser-diode is presented. A 2.73 W absorbed pump power is used to generate a maximum laser output of 470 mW, representing a 17.2% optical-to-optical conversion efficiency and a 61.7% slope efficiency corresponding to absorbed power. In the experiment, the oscillating wavelength shifting from 2.03 to 2.08 µm has been observed and a single 2.03 µm wavelength oscillation has obtained. To our knowledge, this work is the first time to investigate the Cryogenic temperature operation of microchip Tm,Ho:Lu2SiO5.

An apparatus is described for studying industrial RF assisted processes, on the laboratory scale. The applied electromagnetic field can be as intense as that used in industry; it can be varied for performing step changes, constant temperature, or constant absorbed power experiments. The thermal environmental conditions of the product can also be controlled. The permittivity is continuously measured so that the energy balance is carefully established.Results concerning the study of PVC-plastisol gelation will illustrate the performances of the apparatus and illustrate how modeling of the process can be done.

The general approach to Alfvén-wave current drive and induced plasma rotation in tokamaks with strongly elongated transverse cross-sections is considered. Model approximations are used to describe the circulating- and trapped-particle dynamics in all particle-trapping regions. This approach gives an accuracy of some percent. New terms, connected with the wave dissipation on trapped particles in the second and third trapped-particle regions for elongated tokamaks, are taken into account. The plasma rotation and longitudinal current, depending on the absorbed power of kinetic Alfvén waves, are discussed.

The power absorbed by 12 male subjects during exposure to vertical whole-body vibration at six magnitudes of random vibration (0·25, 0·5, 1·0, 1·5, 2·0 and 2·5 ms−2r.m.s.) has been measured in the laboratory. All subjects showed greatest absorbed power at about 5 Hz, but the frequency of this peak in the absorbed power reduced with increasing vibration magnitude. The total absorbed power increased approximately in proportion to the square of the acceleration magnitude: normalizing the absorbed power to the square of the r.m.s. vibration magnitude removed most of the differences, although the changes in resonance frequency were still evident. The frequency dependence of absorbed power at a constant magnitude of acceleration was approximated by a simple weighting having slopes of ±6 dB/octave either side of 5 Hz. Comparing the characteristics of this absorbed power weighting to standard frequency weightings showed substantial differences, especially at high frequencies. It is concluded that the differences from currently accepted frequency weightings are so great that the absorbed power is unlikely to yield good general predictions of the discomfort or risks of injury from whole-body vertical vibration.

Electrodynamic characteristics of the tunable cavity plasma source, as well as the optical and chemical properties of a nonequilibrium microwave plasma generated in this type of plasma device are presented. Some characteristic features of the adjustable length rectangular cavity plasma generator are described: (i) the possibility of continuing varying the plasma absorbed power without any variation of the incident microwave power, and (ii) the possibility of variation in the internal spatial structure of plasma. Products of methane decomposition in Ar+1% CH4 and Ne+1% CH4 microwave plasmas are compared with those measured in the positive column of a DC discharge under similar external parameters. The observed differences in the gas component concentrations and in the yields in the condensed phase are within a factor of three for both discharges, and can be attributed to distinctions in the internal structure of the discharges. These results are in agreement with previous theoretical considerations.

Using acoustic methods we have measured nonlinear AC conductance in 2D arrays of Ge-in-Si quantum dots. The combination of experimental results and modeling of AC conductance of a dense lattice of localized states leads us to the conclusion that the main mechanism of AC conduction in hopping systems with large localization length is due to the charge transfer within large clusters, while the main mechanism behind its non-Ohmic behavior is charge heating by absorbed power., Comment: 5 pages, 7 figures

This paper is focused on the vibration effects produced by an array of decentralised velocity feedback loops that are evenly distributed over a rectangular thin plate to minimise its flexural response. The velocity feedback loops are formed by collocated ideal velocity sensor and point force actuator pairs, which are unconditionally stable and produce ‘sky-hook’ damping on the plate. The study compares how the overall flexural vibration of the plate and the local absorption of vibration power by the feedback loops vary with the control gains. The analysis is carried out both considering a typical frequency-domain formulation based on kinetic energy and structural power physical quantities, which is normally used to study vibration and noise problems, and a time-domain formulation also based on kinetic energy and structural power, which is usually implemented to investigate control problems. The time-domain formulation shows to be much more computationally efficient and robust with reference to truncation errors. Thus it has been used to perform a parametric study to assess if, and under which conditions, the minimum of the kinetic energy and the maximum of the absorbed power cost functions match with reference to: (a) the number of feedback control loops, (b) the structural damping in the plate, (c) the mutual distance of a pair of control loops and (d) the mutual gains implemented in a pair of feedback loops.

A method for thermal processing of food packaging waste using microwaves was developed. The waste material was shredded and compacted into cylinders with added moisture. The cylinders at different densities and moisture contents were processed at three microwave power levels, and at 0 and 15 prig over pressure. Heating rate decreased with density. At 2.83x10-2 W/cm3 absorbed power, locations close to the surface of the material had slower heating rates. At low densities (1.004 g/cm3 to 2.510 g/cm3), heating rate was higher at 40% moisture content than at 35 and 50% moisture contents. At higher densities (3.012 g/cm3 to 4.016 g/cm3) heating rates were higher at 35 and 50% moisture contents. At 4.48x10-2 W/cm3 and 5.85x10-2 W/cm3 absorbed power, heating rate increased with power and was not significantly higher at any specific location. Uniform temperatures of 121°C were attained when the waste samples were heated in an enclosed chamber at 4.48x10-2 W/cm3 absorbed power and 15 psig steam over pressure. Loga...

Using a combined ray tracing and Fokker-Planck code, an investigation is made on the propagation and absorption of the launched power spectrum during lower hybrid (LH) current drive in tokamaks, in a situation where toroidally induced ray stochasticity is important. Stochastic effects are correctly taken into account by tracing a large number of rays. The influence of the balance between the wave damping and the stochastic divergence of nearby ray trajectories in governing the power spectrum dynamics and in establishing the characteristics of the LH power deposition patterns is illustrated. It is shown that, when strong wave damping prevails, the launched power spectrum behaves regularly: the LH power deposition is localized and the absorbed power spectrum is very similar in shape to the launched one, although some broadening and shifting in the parallel wave index generally occur. If the wave damping is weak and stochastic effects are important, the rays end by covering the entire plasma cross-section and the power spectrum dynamics follows a diffusive pattern: the LH power deposition turns out to be extended and the absorbed power spectrum is much broader than the launched one, as a result of strong spreading towards the high absolute values of the parallel wave index

Soybeans were rewetted to selected levels of initial moisture content and then dried in a microwave field under various conditions of microwave power and inlet air condition. An empirical diffusion model, based on the assumption that the surface moisture content is an exponentially decreasing function of the initial free moisture content, fit the data very well. This modelling technique resulted in goodfits to independent data on soybean drying. Tests showed that soybeans may be dried in a microwave field much more rapidly than by convection alone, with no reduction in germination for absorbed power levels below 0.13 W/g.

This paper considers the heating mix of ITER for the two main scenarios. Presently, 73 MW of absorbed power are foreseen in the mix 20/33/20 for ECH, NBI and ICH. Given a sufficient edge stability, Q = 10-the goal of scenario 2-can be reached with 40MW power irrespective of the heating method but depends sensitively inter alia on the H-mode pedestal temperature, the density profile shape and on the characteristics of impurity transport. ICH preferentially heats the ions and would contribute specifically with Delta Q < 1.5. The success of the Q = 5 steady-state scenario 4 with reduced current requires discharges with improved confinement necessitating weakly or strongly reversed shear, f(bs) > 0.5, and strong off-axis current drive (CD). The findings presented here are based on revised CD efficiencies gamma for ECCD and a detailed benchmark of several CD codes. With ECCD alone, the goals of scenario 4 can hardly be reached. Efficient off-axis CD is only possible with NBI. With beams, inductive discharges with f(ni) > 0.8 can be maintained for 3000 s. The conclusion of this study is that the present heating mix of ITER is appropriate. It provides the necessary actuators to induce in a flexible way the best possible scenarios. The development risks of NBI at 1 MeV can be reduced by operation at 0.85 MeV.

Drying kinetics of seed corn was studied under constant and variable microwave power operating modes. The absorbed microwave power levels were 0.25 W/g, 0.50 W/g, and 0.75 W/g of wet grain. Heated air at 30°C was used to carry moisture from the grain bed. For constant microwave power operation, the total drying time was reduced from 5.0 hr to 3.5 hr and 2.25 hr, respectively, when the absorbed power was increased from 025 W/g to 050 W/g and 0.75 W/g. However, after about 2 hr the drying rates fell to approximately the same level regardless of the absorbed power. The outgoing air temperature, an indicator of the grain temperature, increased with the increase in absorbed power. The germination of the corn dried at 0.25 W/g was 94% while it dropped to 53% and 44% respectively for 0.50 W/g and 0.75 W/g absorbed power. Bulk density of the corn dried at 0.25 W/g power was 0.735 g/cc and it was reduced to 0.712 glcc and 0.706 glcc respectively for 0.50 W/g and 0.75 W/g absorbed microwave power. Variable microwav...

In JT-60, H-mode experiments with outer and lower divertors have been performed. In the outer divertor discharge, an H-mode similar to the modes observed in the lower/upper divertor discharges is obtained. Its threshold absorbed power and electron density are 16 MW and 1.8 × 1019 m−3. In the two schemes of combined heating with NB + ICRF and NB + LHRF, H-mode discharges are also obtained. Moreover, in the new configuration with the JT-60 lower divertor, H-mode phases with and without edge localized modes are obtained. The improvement in the energy confinement time in both divertor configurations is limited to values within 10%. The paper mainly presents the H-mode results of the outer divertor discharges. Also, typical results of the lower divertor discharges are shown for a comparison of the H-mode characteristics of the two configurations.

This paper describes a computer control method for sintering dielectric materials by microwave heating. The algorithm used allows control of either the surface temperature of the sample or the absorbed power. The experimental results compare favorably with those of classical sintering methods.

Full wave simulations of fusion plasmas show a direct correlation between the location of the fast-wave cut-off, radiofrequency (RF) field amplitude in the scrape-off layer (SOL) and the RF power losses in the SOL observed in the National Spherical Torus eXperiment (NSTX). In particular, the RF power losses in the SOL increase significantly when the launched waves transition from evanescent to propagating in that region. Subsequently, a large amplitude electric field occurs in the SOL, driving RF power losses when a proxy collisional loss term is added. A 3D reconstruction of absorbed power in the SOL is presented showing agreement with the RF experiments in NSTX. Loss predictions for the future experiment NSTX-Upgrade (NSTX-U) are also obtained and discussed.

In this paper, a complete electromagnetic and thermal analysis has been performed considering the head of a subject exposed to various kinds of cellular phones available on the market, and focusing the attention on important organs like the eye lens and brain. Attention has first been posed on a particular phone model, and a comparison between the absorbed power distribution and steady-state temperature increases has been carried out. The influence of different antennas (dipole, monopole, whip, and planar inverted F antenna) on the power absorption and on the consequent tissue heating has then been analyzed. The obtained results show for a radiated power of 600 mW, maximum SAR values, averaged over 1 g, from 2.2 to 3.7 W/kg depending on the considered phone. The maximum temperature increases are obtained in the ear and vary from 0.22/spl deg/C to 0.43/spl deg/C, while the maximum temperature increases in the brain lie from 0.08/spl deg/C to 0.19/spl deg/C. These steady-state temperature increases are obtained after about 50 min of exposure, with a time constant of approximately 6 min. Finally, the results evidence a maximum temperature increase in the external part of the brain from 0.10/spl deg/C to 0.16/spl deg/C for every 1 W/kg of SAR, averaged over 1 g of brain tissue.

Correlations between the external discharge parameters (the driving frequency ω and the chamber dimension R) and plasma characteristics (the skin depth δ and the electron-neutral collision frequency νm) are studied using the transformer circuit model [R. B. Piejak et al., Plasma Sources Sci. Technol. 1, 179 (1992)] when the absorbed power is maximized in an inductively coupled plasma. From the analysis of the transformer circuit model, the maximum power transfer conditions, which depend on the external discharge parameters and the internal plasma characteristics, were obtained. It was found that a maximum power transfer occurs when δ≈0.38R for the discharge condition at which νm/ω≪1, while it occurs when δ≈2ω/νmR for the discharge condition at which νm/ω≫1. The results of this circuit analysis are consistent with the stable last inductive mode region of an inductive-to-capacitive mode transition [Lee and Chung, Phys. Plasmas 13, 063510 (2006)], which was theoretically derived from Maxwell's equations. Our...

The E–H mode transition and hysteresis in low pressure argon inductively coupled discharges are investigated using a global model and a transformer model. The total absorbed power by the plasma and the coil current are calculated as a function of the electron density at fixed RF injected power rather than fixed RF coil current as previously shown in the literature. We found that the transition corresponds to a difference of the absorbed power efficiency between E and H mode. The calculation results show the existence of an inaccessible region between E and H mode as well as a threshold coil current and a minimum absorbed power for the H mode. Hysteresis is well reproduced by this simple calculation and can be directly compared with experimental data.

The relative absorbed power of polarized light is calculated for copper thin films by means of Green's functions technique and ECPA approach. A mechanism of polarized light absorption on the electrically neutral as well as electrically charged films is analysed. It is concluded that the crystallographic structure and a volume charge parameter play the most important role in light absorption. Mittels der Technik Greenscher Funktionen und der ECPA-Naherung wird die relative absorbierte Leistung von absorbiertem Licht fur diinne Kupferschichten berechnet. Ein Mechanismus der Absorption des polarisierten Lichts von elektrisch neutralen sowie elektrisch geladenen Schichten wird analysiert. Es wird nngenommen, das die kristallographische Struktur und ein Volumen-ladungsparameter , die wesentlichste Rolle bei der Lichtabsorption spielen.

A low-power CW microwave discharge at 2.45 GHz was used to produce XeO* excimer molecules. It was found that a total gas pressure between 5 and 20 Torr, absorbed power of about 20–100 W, and an oxygen-to-xenon ratio of 1∶100 maximized the XeO(1S−1D) green emission at 5200 to 5600 A. The XeO* emission appeared in the cooler parts of the discharge near the containment tube walls and in the electric field nodes of the TM012 resonant mode.

Microwave irradiation at 960-MHz CW of isolated poikilothermic hearts in Ringer's solution causes bradycardia. Tachycardia is usually produced by generalized heating, suggesting the possibility of a different mechanism in this case. The effect occurs only over a narrow power range of approximately 2-10 mW/g absorbed by the heart. It is hypothesized that microwave radiation causes neurotransmitter release either by excitation of the nerve remnants in the heart, or by some other mechanism, producing bradycardia over a restricted range of power absorption. Drugs which can change the response of the heart to transmitter substances have been used, and the results support a neurotransmitter release hypothesis. A generalized heating effect, causing tachycardia, is predominant at higher levels of absorbed power.

Data obtained on superficial lesions in different sites and for different patients show that it is possible to correlate average values of the temperature and of the absorbed power density. For healthy tissues, the correlation appears to be defined to within 1/spl deg/C. For tumor tissues, on the other hand minimum values of the temperature appear to be predictable. This result indicates that hyperthermic dosimetry is feasible. Furthermore, a differential temperature phenomenon is observed, in which a lacalized absorbed power distribution induces higher temperatures in tumors than in the surrounding healthy tissues. This observation, if confirmed with larger statistics and for tumors at a depth, appears to indicate that tumor-killing temperatures can be induced with the heating method employed while simultaneously sparing the surrounding healthy tissues.

A study is made on the scheme of heating a local region of a biological body by utilizing an EM field and increasing the conductivity of the local region. It was found that when the frequency of the EM field is in the range of 1 to 100 MHz, the increase of the conductivity of the local region usually causes a decrease, instead of an increase, of the absorbed power in that local region. For a microwave EM field, there may exist an optimum conductivity for the local region to gain the most effective EM heating.

The entropy of a noninteracting dipole system with the equilibrium dipole moment μ ‖ 〈100〉 in a rigid cubic lattice is obtained for the external electric field E‖ [100] of arbitrary strength, taking into account the 90° tunneling. In thermostating experiments the KCI-OH monocrystals were illuminated with light pulses of rectangular shape (single 10−2 s shots, absorbed power ranging 3 × 103 erg/s cm3) and the electric field applied to the crystal was simultaneously removed. The electric field pulse shape, needed for maintaining the crystal temperature constant within some millidegrees at 0.75 K, is close to the theoretical one assuming a “working” dipole number NE ≈ 0.1Nopt. [Russian Text Ignored].

Numerical results on the internal electromagnetic (EM) field and absorbed power density inside a human torso induced by EM waves of frequencies ranging from 1 to 500 MHz and of both vertical and horizontal polarizations are presented. The induced fields inside the torso are shown to be dependent on the frequency and the torso geometry. Theoretical results are obtained based on the tensor integral equation method and some theoretical predictions are compared to existing experimental results.

A surge in absorbed power by a heterogeneous catalyst placed in an RF field was observed at high temperatures. This phenomenon has been explained by the dielectric behaviour of the material. A transition in dielectric behaviour from low to high loss is sensitive to both temperature and chemisorbed water and will cause thermal fluctuations in the catalyst.

To determine the spectral absorptance of a material the authors use a method that modulates the monochromatic radiation incident on the specimen and directly compares the absorbed power with electrical power released in the specimen.

Current drive by radiofrequency waves is considered for a preionization plasma. The ratio J/P of the driven current density and the absorbed power density is computed, taking into account both Coulomb and electronneutral collisions. A considerable modification of the fully ionized plasma case is found.

The dependence of carrier-phonon interaction on dimensionality and on quantum well thickness is studied in bulk Ga 0.47 In 0.53 As and in 3.4, 8.0, and 13.8 nm thick Ga 0.47 In 0.53 As/Al 0.48 In 0.52 As quantum well structures. The variation of carrier temperature with absorbed power in a steady-state photoluminescence experiment yields effective longitudinal optical phonon energies and carrier-polar optical scattering times, which are within experimental error independent of sample structure and agree with the theoretical value.

Statistical samples of quad 2-input NAND gates (CMOS) were submitted to electrostatic discharge (ESD) according to MIL specifications. The tests were performed at five levels of ESD. Failure thresholds for the devices were measured, and using reliability models such as the Normal, the Two-Parameter Exponential and the lognormal, reliability and hazard rate plots have been generated as functions of absorbed power. An ESD adjacent circuit sensitivity analysis was also performed.

The power absorbed by a surface at 0.2 K illuminated with thermal radiation from a surface at 0.9–6 K has been measured using a variety of materials for these surfaces. Also, the reduction in the absorbed power by the insertion of various thermal shields has been measured. The results are compared with theory and with other measurements. Conclusions as to appropriate design techniques for cryogenic apparatus are discussed.

The influence of an ac current of arbitrary amplitude and frequency on the mixed-state dc-voltage-ac-drive tiltingratchet response of a superconducting film with uniaxial cosine pinning potential at finite temperature is theoretically investigated. The results are obtained in the single-vortex approximation, within the frame of an exact solution of the Langevin equation for non-interacting vortices. Both experimentally achievable, the dc ratchet response and absorbed ac power are predicted to demonstrate a pronounced filter-like behavior at microwave frequencies. Based on our findings, we propose a cut-off filter and discuss its operating curves as functions of the driving parameters, i.e, ac amplitude, frequency, and dc bias. The predicted results can be examined, e.g, on superconducting films with a washboard pinning potential landscape.

The low-frequency automodulation of r.f. power, absorbed at antiferromagnetic resonance, is discovered at temperatures below 1K. The effect is shown to be caused by non-linear oscillations of occupation numbers of magnons, excited by r.f. pumping.