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In this paper, a controller for a doubly fed induction generator (DFIG) connected to a wind system is proposed. This control assigning its own structures as an optimal control method, the electric model in the DFIG state space is also shown, for which it is expected to estimate a linear model through the subspace technique and thus to design the controller. It will be possible to show that a structure assignment controller is undoubtedly a good option for the control of multivariable systems. The results of the output signals will be analyzed when applying the controller, assigning their own structures, which will allow us to observe that the response and disturbance times are below two tenths of a second.

For a time, each new processor churned out more waste heat than the last. Had these chips kept on the trajectory they were following in the early 2000s, they would soon have packed about 6,400 watts onto each square centimeter-the power flux on the surface of the sun.

The fundamental problem of propagation invariant Bessel beams is that they are not square-integrable in the transverse direction, and are therefore associated with an infinite power flux. H...

In modern practical medicine, along with pharmacological agents, more and more attention is paid to physiotherapeutic methods. Over the past decades, extremely high-frequency therapy (EHF-therapy) has been widely used. The electromagnetic radiation of the EHF range is used in medicine not only as a therapeutic, but also as a diagnostic tool. At the moment, there are various methods for determining individual sensitivity to EHF-therapy at the cellular level of patients with cardiovascular diseases, although this method of physiotherapy is also successfully used to treat neurological diseases. A cytobiophysical technique was developed and studied to determine individual sensitivity to EHF-therapy in neurology. The technique is based on determining the number of negatively charged nuclei of the patient’s buccal epithelium cells before and after exposure to cells of electromagnetic radiation from the EHF range and comparing the obtained parameters to determine individual sensitivity to EHF therapy. The measurements were carried out using buccal epithelium of conditionally healthy donors 24–35 years old of both sexes (n=8), as well as patients with degree I and II degree discirculatory encephalopathy at the age of 41–77 years (n=55) who were hospitalized. A generator of type G4-141 served as a source of EHF radiation, irradiation was carried out at a wavelength of λ=7,1 mm, and a power flux density of 10 mW/cm2. The cytobiophysical technique allows us to solve the problem of individualization in the case of EHF-therapy, since the current approaches to the treatment of patients with discirculatory encephalopathy require maximum individualization of treatment and a combination of drug treatment with physiotherapeutic methods of treatment. The cytobiophysical technique is easy to use, non-invasive, painless for the patient, allows you to determine individual sensitivity to EHF-therapy for various pathologies, and also allows you to quickly (study time is 15–20 minutes) to monitor the effectiveness of any type of therapy, including EHF-therapy at all stages of treatment.

There is increasing interest in applications which use the 30 to 90 GHz frequency range, including automotive radar, 5 G cellular networks and wireless local area links. This study investigated pulsed 30–90 GHz radiation penetration into the human ear canal and tympanic membrane using computational phantoms. Modelling involved 100 ps and 20 ps pulsed excitation at three angles: direct (orthogonal), 30° anterior, and 45° superior to the ear canal. The incident power flux density (PD) estimation was normalised to the International Commission on Non-Ionizing Radiation Protection (1998) standard for general population exposure of 10 Wm−2 and occupational exposure of 50 Wm−2. The PD, specific absorption rate (SAR) and temperature rise within the tympanic membrane was highly dependent on the incident angle of the radiation and frequency. Using a 30 GHz pulse directed orthogonally into the ear canal, the PD in the tympanic membrane was 0.2% of the original maximal signal intensity. The corresponding PD at 90 GHz was 13.8%. A temperature rise of 0.032° C (+20%, −50%) was noted within the tympanic membrane using the equivalent of an occupational standard exposure at 90 GHz. The central area of the tympanic membrane is exposed in a preferential way and local effects on small regions cannot be excluded. The authors strongly advocate further research into the effects of radiation above 60 GHz on the structures of the ear to assist the process of setting standards.

For a first-order quasilinear equation with power flux function, a generalized entropy solution of the Cauchy problem with exponential initial condition is constructed. An example of a nonunique generalized entropy solution in the class of locally bounded functions of the Cauchy problem with zero initial condition is given.

Recently, there has renewed and growing interest in the characterization of spin (SAM) and orbital (OAM) angular momentum (OAM) of electromagnetic waves, with a view to potential applications in increasing capacity of wireless communication systems. Both the generation and the accurate detection and evaluation of OAM in reference and real-life electromagnetic environments is posing new challenges.

Wave mixing of ultrasonic guided wave has attracted considerable attention because of its potential for localizing micro-damage in plate-like structures. Non-zero power flux and phase-velocity matching are regarded as the necessary conditions for generating cumulative harmonics. However, selecting a high-efficiency Lamb mode with obvious difference or sum harmonics remains problematic in practice. In this paper, experiment and numerical simulations have been performed to investigate the excitation efficiency of mode pairs that satisfy resonance conditions. The result shown that a mode pair (S0 mode at 1.2MHz and S0 mode at 3.0MHz can generate the S2 mode at 4.2MHz) has more obvious harmonics than other mode pairs. We could find that the potential of the excitation efficiency simulation on selecting mode pairs with obviously harmonics.

Analytical and numerical analysis of electromagnetic wave propagation in cylindrical waveguides filled with isotropic metamaterial is presented. Emphasis is given to the characteristics of power flux in the waveguide. In the structure of the waveguide, The characteristics equation for the modes in this waveguide is obtained. The behavior of the dispersion curves and the energy flux are examined theoretically. The negative energy flux propagation through the cylindrical waveguide is confirmed.

Five-layer slab a waveguide combined with a metamaterial has been studied. The central layers were the metamaterial and a normal material in the core of waveguide. The dispersion relation, field formulas, power formulas and the power flux formula has been derived. The waveguide property was controlled by changing the permittivity and permeability and thicknesses of the layers. The presence of metamaterial contributes to cut-off the mode TEo and other modes were propagated to backward. The stopping light was determined using the power flux value. However, the negative values of it refer to the backward direction of propagation. Furthermore the stopped light can be achieved in a certain value of power. Our results found it is good for different applications in communication and controlling.

Background: Exposure to radiofrequency electromagnetic fields (RF-EMF) from mobile communication technologies is changing rapidly. To characterize sources and associated variability, we studied the differences and correlations in exposure patterns between children aged 8 to 18 and their parents, over the course of the day, by age, by activity pattern, and for different metrics of exposure. Methods: Using portable RF-EMF measurement devices, we collected simultaneous real-time personal measurements of RF-EMF over 24 to 72 h in 294 parent-child pairs from Denmark, the Netherlands, Slovenia, Switzerland, and Spain. The devices measured the power flux density (mW/m(2)) in 16 different frequency bands every 4 s, and activity diary Apps kept by the participants were used to collect time-activity information in realtime. We analyzed their exposures by activity, for the different source constituents of exposure: downlink (radiation emitted from mobile phone base stations), uplink (transmission from phone to base station), broadcast, DECT (digital enhanced cordless telecommunications) and Wi-Fi. We looked at the correlations between parents and children overall, during day (06:00-22.00) and night (22:00-06:00) and while spending time at home. Results: The mean of time-weighted average personal exposures was 0.16 mW/m(2) for children and 0.15 mW/m(2) for parents, on average predominantly originating from downlink sources (47% for children and 45% for parents), followed by uplink (18% and 27% respectively) and broadcast (25% and 19%). On average, exposure for downlink and uplink were highest during the day, and for Wi-Fi and DECT during the evening. Exposure during activities where most of the time is spent (home, school and work) was relatively low whereas exposure during travel and outside activities was higher. Exposure to uplink increased with age among young people, while DECT decreased slightly. Exposure to downlink, broadcast, and Wi-Fi showed no obvious trend with age. We found that exposure to total RF-EMF is correlated among children and their parents (R-speannan = 0.45), especially while at home (0.62) and during the night (0.60). Correlations were higher for environmental sources such as downlink (0.57) and broadcast (0.62) than for usage-related exposures such as uplink (0.29). Conclusion: The generation gap between children and their parents is mostly evident in uplink exposure, due to more and longer uplink and cordless phone calls among parents, and their tendency to spend slightly more time in activities with higher environmental RF-EMF exposure, such as travel. Despite these differences in personal behavior, exposure to RF-EMF is moderately correlated between children and their parents, especially exposures resulting from environmental RF-EMF sources., GERoNiMO project: This work was supported by funding from the European Commission Seventh Framework Programme under grant agreement number FP7 603794.r HERMES project: This work is supported by the Swiss National Science Foundation (project number 138190). This research is also supported by the Swiss Research Foundation for Electricity and Mobile Communication (reference number 41).r ABCD, The Netherlands: This work is supported by the Netherlands Organisation for Health Research and Development (grant 2100.0076) and within the programme Electromagnetic Fields and Health Research (grants 85600004 and 85800001).r DNBC, Denmark: This work is supported by the Danish Epidemiology Science Centre; The Lundbeck Foundation; Egmont Foundation; March of Dimes Birth Defect Foundation; Augustinus Foundation; and the Medical Research Council.r ZuMe, Switzerland: This work is supported by the AWEL (Office for Waste, Water, Energy and Air) in Zurich.r INMA, Spain: This study was funded by grants from Instituto de Salud Carlos III (Red INMA G03/176; CB06/02/0041; PI041436; PI081151 incl. FEDER funds; PI12/01890 incl. FEDER funds; CP13/00054 incl. FEDER funds; MS13/00054), CIBERESP, Generalitat de Catalunya-CIRIT 1999SGR 00241, Generalitat de Catalunya-AGAUR (2009 SGR 501, 2014 SGR 822), Fundacio La marato de TV3 (090430), Spanish Ministry of Economy and Competitiveness (SAF2012-32991 incl. FEDER funds), Agence Nationale de Securite Sanitaire de l'Alimentation de l'Environnement et du Travail (1262C0010), European Commission (261357, 308333 and 603794). ISGlobal is a member of the CERCA Program, Generalitat de Catalunya.

The solid angle for \(\tan {\theta }\) = 20 km/40 km, or θ=26.5o. This is \(\varOmega = 2\pi \int _0^{\theta }\ \sin {\theta }\ \mathrm {d} \theta = 2\pi (1 - \cos {\theta })\) = 0.663 steradians. By inserting the numbers, the flux is determined to be 2 10−10 W m−2. To reach the edge of a city with a radius of 20 km, this is 47.7 km from the transmitter, with the required power flux the radiated power must be P = 2 × 10−10 W m−2 × [(47.7 × 103)]2 m2 = 0.4 W. This is a very small quantity. The danger level is at a distance R, where the flux reaches 0.4 W/R2 = 10−2W, so R = 6.3 m. This is a proposal put forth by Facebook.

In this meta-study, the major forms of thorium based nuclear reactors were compared using thermodynamic parameters to find which reactor type holds the highest thermodynamic efficiency and hence, determine which reactor would be most beneficial to research further and implement for energy production. Our study found that molten salt reactors had the best thermodynamic efficiency and also runs at one atmospheric pressure, making it safer than conventional water reactors. The findings in this study show molten salt reactors would be the most efficient reactor to replace standard water reactors, which dominate the market in use of nuclear energy production. This study found a strong link between the thermal efficiency of the plant and the pressure and temperature at which it runs. Reactor core volumes also appeared to have a small effect on the efficiencies. Power flux density was calculated for each style of reactor and compared to other parameters but no distinct relationship was found between them.

The narrow scrape-off layer power component observed in COMPASS inner wall limiter circular discharges by means of IR thermography is investigated by Langmuir probes embedded in the limiter. The power flux profiles are in good agreement with IR observations and can be described by a double-exponential decay with a short decay length (

The problem of solving the dispersion relations for waves in guiding electrodynamic structures on the complex planes of wavenumbers is considered. A method combining the positive features of the Muller method and the phase variation method based on the argument principle is proposed. The implementation of the method is described. For estimating the correctness of the solutions obtained, a new approach employing the convergence to zero of the period-averaged power flux of complex waves is suggested.

Microwave irradiation of animals on the frequency of the resonance transparency of aqueous media at the power flux density 10 NW/cm2 didn’t accompanied by a statistically significant effect on the severity of experimental acute respiratory distress syndrome. Analysis of the distribution of pulmonary index, as an indicator of the severity of the alveolar-capillary disorders, suggests that while the power flux density of microwave radiation 10NW/cm2, its normalization occurs in 40% of the animals. It is noted that in this capacity, there is a reduction in the proportion of animals with lung index in the range of 8-12% from 60 to 20% (p=0.011). The statistical analysis revealed significant differences distributions it absolute values in this group and the comparison group, in which microwave irradiation hasn’t been conducted (χ2=36,4; р=0,001). Microwave irradiation with the power flux density 50 NW/cm2 is manifested by normalization of pulmonary index in 83% of the animals. However, in 17% of animals subjected to such exposure it was noted the high conservation values of the index, which doesn’t exceed 12 units. The increase of power of microwave radiation of up to 80 NW/cm2 is accompanied by normalization of the manifestations of acute distress syndrome in 77% of the animals (p

The influence of microwave radiation with a power flux density of 80 W/cm2 and carrier frequency of 9.4 GHz on the thermal stability of aluminum nanopowder after irradiation in air is studied. It is established that, after irradiation, the chemical activity of aluminum nanopowder increases, the temperature for the beginning of its oxidation decreases by 40°, while the thermal effect of oxidation decreases by 13.5%.

In this paper a method is described which allows estimating the power flux brought by an electric arc on the electrodes. This information is highly important for the understanding of contact erosion mechanisms, as well as for the practical choice of appropriate materials and sizes in switching devices applications. Our method is applied to the case of Ag-SnO 2 electrodes. Compatibility conditions between experimental values of mass loss in well-defined situations and numerical calculations of melted/vaporized metal lead to a maximum surface power density of 8×109 W/m2 for cathode and 2×109 W/m2 for anode. Moreover it is found that less than 16% of the total power brought to the electrodes contributes to metal phase changes.

One of the major concerns in the design and performance of satellite communications links is the possible effects of interference on the communications link. This chapter reviews the types of interference affecting satellite communications and provides several specific analysis tools and parameters used to quantify interference and mitigate its effects on system performance. Understanding the source of the interference is the first step in developing mitigation techniques for interference avoidance or reduction. Interference signals can be introduced to the satellite system through several propagation conditions (or mechanisms) that may be present in the region of the satellite link. The presence of unwanted signals on the radio frequency (RF) link produces the potential for interference degradations on the performance of the satellite network. The primary parameter involved in the evaluation of interference is the power flux density (pfd).

On the eve of component procurement, this paper discusses the present physics basis for the first ITER tungsten (W) divertor, beginning with a reminder of the key elements defining the overall design, and outlining relevant aspects of the Research Plan accompanying the new “staged approach” to ITER nuclear operations which fixes the overall divertor lifetime constraint. The principal focus is on the main design driver, steady state power fluxes in the DT phases, obtained from simulations using the 2-D SOLPS-4.3 and SOLPS-ITER plasma boundary codes, assuming the use of the low Z seeding impurities nitrogen (N) and neon (Ne). A new perspective on the simulation database is adopted, concentrating purely on the divertor physics aspects rather than on the core-edge integration, which has been studied extensively in the course of the divertor design evolution and is published elsewhere. Emphasis is placed on factors which may increase the peak steady state loads: divertor target shaping for component misalignment protection, the influence of fluid drifts, and the consequences of narrow scrape-off layer heat flux channels. All tend to push the divertor into an operating space at higher sub-divertor neutral pressure in order to remain at power flux densities acceptable for the target material. However, a revised criterion for the maximum tolerable loads based on avoidance of W recrystallization, sets an upper limit potentially ∼50% higher than the previously accepted value of ∼10 MW m−2, a consequence both of the choice of material and the finalized component design. Although the simulation database is currently restricted to the 2-D toroidally symmetric situation, considerable progress is now also being made using the EMC3-Eirene 3-D code suite for the assessment of power loading in the presence of magnetic perturbations for ELM control. Some new results for low input power corresponding to the early H-mode operation phases are reported, showing that even if realistic plasma screening is taken into account, significant asymmetric divertor heat fluxes may arise far from the unperturbed strike point. The issue of tolerable limits for transient heat pulses is an open and key question. A new scaling for ELM power deposition has shown that whilst there may be more latitude for operation at higher current without ELM control, the ultimate limit is likely to be set more by material fatigue under large numbers of sub-threshold melting events. Keywords: ITER, Tungsten, Divertor, Heat fluxes, SOLPS

A method for the uncertainty estimation of probe calibrations using the power flux density (PFD) system of (18~26.5) GHz recently developed at the National Institute of Metrology, China is presented. A measurement model is developed first, and then the sources of uncertainty and the corresponding evaluation procedures are explained. The method is used to estimate the uncertainty of the calibration factor of a FP7050 probe at 18 GHz obtained by the PFD system. The good agreement between the calibration results from two PFD systems validates the method.

An experiment aimed at benchmarking the ITER scrape-off layer (SOL) power width scaling in limited L-mode discharges has been conducted on DIII-D. Scans of the main scaling parameters were performed in an inner-wall-limited (IWL) magnetic configuration. Using the near-SOL density and temperature e-folding lengths, λ n , λ T , determined from reciprocating Langmuir probe measurements, SOL power flux density e-folding lengths, λ q , are derived. A few lower single null (LSN) discharges were also run for comparison. The results are generally in agreement with the ITER design assumptions, finding that λ n and λ T are correlated ( λ T ∼ 1.2 λ n ) and both λ n and λ T are on average 2.1–2.5 times larger in IWL configurations than in LSN. In moderate elongation (κ ∼ 1.4) IWL discharges, λ q is largest and agrees with the assumed ITER scaling within the estimated uncertainty (a factor of ∼2). In IWL discharges λ q measurements are consistent with the expectations of SOL power balance.

The ITER First Wall is being redesigned to address a number of issues identified during the 2007 design review. One of the main improvements concerns the handling of parallel plasma heat loads. The design must be optimised for maximum leading edge protection with acceptable power flux distribution, which is achieved by shaping the First Wall panels. The conceptual design presented in the paper can accommodate both inboard and outboard limiter plasmas for a total power in the discharge of 7.5 MW at 7.5 MA and allows the abandonment of the original dedicated port limiters.

This article introduces the new divertor design for the planned upgrade to HL-2A and details the optimization of the divertor parameters, including the target geometry, throat width, and the size and location of the pumping chamber entrance. The basic requirements are to provide tolerable power loads on the target plates and sufficient particle exhaust for the Ip = 1.2MA, 10–20 MW auxiliary heated reference discharge. The SOLPS5.0 code package is used to generate a database. A vertical target divertor configuration has been adopted as the first conceptual design, which gives a peak heat load on the divertor target of 4–10 MW/m 2 for an anticipated power flux into the SOL of 5–10 MW discharge. The pumping efficiency is found to increase by a factor of 3–4 when the divertor gap is narrowed from 5.5 to 2.0 cm.

19th International Conference on Plasma-Surface Interactions in Controlled Fusion Devices (PSI), Univ Calif, Gen Atom, San Diego, CA, MAY 24-28, 2010; International audience; Experiments and theoretical investigations of surface temperature measurement in the medium and long wavelength infrared range carried out on MAST show that a nonhomogenous surface temperature distribution due to the surface state (micro-metric hot-spots and/or surface roughness) can lead to a significant difference (up to similar to 40%) between both wavelengths. The over-estimation of the bulk temperature decreases with wavelength and the discrepancy observed on MAST can be reproduced using a hot-spot simulation model, by varying the dust size and the dust coverage such that a coverage of 0.2 parts per thousand with 1 mu m dust size which is consistent with the observations. The over-estimation of the bulk temperature is assessed at medium and long wavelength as a function of dust contribution (coverage/size). The effect is also assessed in different conditions (temperature of the bulk as well as the incident power flux). (C) 2010 Elsevier B.V. All rights reserved.

The effect (earlier discovered) of penetration of an electromagnetic-field power flux into a wall exhibiting perfect mixed anisotropic conductivity is considered in more detail. It is shown that the power transmitted into the screen through the nodes of conductivity lines and through resonance-length closed contours can be regarded as the limit value of the power absorbed in a wall characterized by an anisotropic impedance when the absorbing impedance approaches the values corresponding to the case of perfect mixed conductivity.

The considerable development of modern technology during last decades has been accom-panied by improvements in associated adapted machines� performance. The improvement process has always been guided by the same rules of researching higher efficiency and more secure effects each time. This leads to a progressive transfer of human action to more adapted and more specific effecting objects, from simple tools for elementary actions to more sophisticated machines for quite complex tasks. Each step of this transfer of human operator action has been realized by delegating to the effecting machine efficiency, accuracy, power and safety�basically all of technical nature and linked to power flux, with the human operator still keeping the mastery of the action to fulfil his own goals.

A method is presented for measuring the aeroacoustic source strength in ducts with flow at frequencies at which the wave motion can be considered substantially one-dimensional. The method is based on coherent power flux measurements using pairs of microphones positioned both upstream and downstream of the source region. The method is applied to a flow excited expansion chamber with aeroacoustic source measurements presented for chambers with a range of flow velocities and chamber lengths. The results indicate locked-on flow tones are generated in the chamber. The frequency of these locked-on flow tones is compared with that predicted using describing function theory applied to resonators with a grazing flow as well as that of other literature.

The influence of millimetric radiation with wave lengths of 4.9, 5.6, and 7.1 mm; a power flux density of 6–10 mW/cm2, and exposures for 2–30 min on dry seeds of different plant species stimulates the germination energy and germination capability of seeds at short exposures (for a few minutes). The method of the presowing treatment of seeds with initially low germination capability by short exposures of millimetric radiation in order to increase the viability of the seeds and the productivity of the plants grown from them has been suggested.

The requirements imposed on the frequency-selection parameters, and also on the sensitivity and screening of the measuring apparatus are established.

This article theoretically studies the conditions for existence of longitudinal or flexural waves in nonlinear, isotropic rods and presents numerical simulations corroborating the theoretical results. It has been known that the existence of guided waves at nonlinearity induced double harmonics is subject to constraints which arise from the potential of power flux transfer from the primary generating mode to the generated higher order modes. The knowledge about the behavior of waves in rods at harmonics higher than double is still limited. This gap was addressed here by the method of perturbation coupled with wavemode orthogonality and forced response. This reduces the nonlinear problem to a forced linear problem which was subsequently investigated to formulate an angular order-based constraint as the condition of existence/nonexistence of nonlinearity-driven higher harmonics of longitudinal and flexural waves in rods.

A four-layer slab waveguide including left-handed material is investigated numerically in this paper. Considering left-handed material dispersion, we find eight TE guided modes as frequency from 4 GHz to 6 GHz. The fundamental mode can exist, and its dispersion curves are insensitive to the waveguide thickness. Besides, the total power fluxes of TE guided modes are analyzed and corresponding new properties are found, such as: positive and negative total power fluxes coexist; at maximum value of frequency, we find zero total power flux, etc. Our results may be of benefit to the optical waveguide technology.

Analysis of the energy principles of system operation permits estimation of the load on the system components in terms of the power flux through the computational element.

Divertor plasma properties for lower single-null (LSN) configuration in EAST, under a water-cooling graphite wall condition, are presented. A typical shot is selected for analyzing electron temperature, density and power flux at targets. Both higher electron density and lower electron temperature are found at the inboard target, compared to those at the outboard target. A higher power flux is also found to be at the outboard target because of in-out asymmetries for LSN-shaped discharge.

Based on an analysis of experimental data and model simulations, the potential of small-size vector hydroacoustic receive systems measuring acoustic power flux (APF) are discussed in application to the detection of weak signals in the presence of ambient sea noise. It is shown that APF receivers are capable of measuring signal levels no less than 10–20 dB lower (depending on the signal-interference situation in the water area) than those measured by PRs. In order to extend the class of hydroacoustic systems whose potential can be correctly compared, it is proposed to modify the definition of interference immunity by introducing two separate qualifying notions: noise and interference.

The terrestrial digital video and audio broadcast are supposed to replace the existing analogue broadcast systems. To determine possible changes of this switchover on the public exposure situation to radio frequency electromagnetic fields, extensive measurements at more than 300 identical points were performed 'before' and accordingly 'after' the switchover. At the point with the highest sum-exposure, only 0.3% of the ICNIRP reference levels for general public exposure (power flux density) was reached. The statistical analysis of both measurement campaigns ('before-after') shows an increase in mean exposure in the centre of the DVB-T starting areas around Nuremberg and Munich, which is mainly based on the increase in the radiated power at the transmitter stations. After developing a simple calculation program based on the ITU-RP.1546, the measured exposure values were compared to calculations. Optimising the results leads to mean deviations of +/-3 dB at about 80% of all points.

We present a detailed description of the features of solar "micro-type III" radio bursts, which are elements of the so-called type III storms, using long-term observations made by the Geotail and Akebono satellites. Micro-type III bursts are characterized by short-lived, continuous, and weak emission. Their average power is estimated to be well below that of the largest type III bursts, by 6 orders of magnitude. When they occur, these bursts have a distribution of emitted power flux that is different from that of ordinary type III bursts, indicating that they are not just weaker versions of the ordinary bursts. Micro-type III burst activity is not accompanied by significant solar soft X-ray activity. We identify the active regions responsible for micro-type III bursts by examining the concurrence of their development and decay with the bursts. It is found that both micro and ordinary type III bursts can emanate from the same active region without interference, indicating the coexistence of independent electron acceleration processes. It is suggested that the active regions responsible for micro-type III bursts generally border on coronal holes.

The far-field radiation of a virtual-cathode triode is studied experimentally. The dependences of the power flux density and frequency on the direction of radiation are obtained for various instants of the generation pulse. The radiation of the virtual-cathode triode is characterized by an intricate directional pattern and variable frequency spectrum.

Actively cooled plasma facing components (PFCs) for Tore Supra (TS) have been designed basically for heat exhaust of ‘normal’ (convected and radiated) plasma power. However, in some cases, fast particles have been observed, which locally increased the power flux density, leading to damage of these PFCs and other inner vessel components. Three different examples for irreversible component damage, such as component melting and water leaks, are described involving runaway and supra-thermal particle strikes. In view of the capability for TS to handle larger input powers and to control the particles over long pulse durations, inner vessel components have been completely redesigned. The improved design concepts retained for the CIEL upgrade and preliminary results in the new configuration are presented.

A total of 550 fertile chicken eggs (White Leghorn) were exposed to a radiofrequency (RF) electromagnetic field of 1.25 GHz (continuous wave) at six different power flux densities in the range of 9.0-0.75 mW/cm(2). The eggs were exposed either continuously throughout the whole 21 days of incubation (long-term exposure) or in a short-term exposure (1-2 h/day). The temperatures of the embryonic tissue and the amniotic fluid, respectively, were measured with inserted temperature probes. This study was designed to investigate the relationship between exposure and temperature changes in exposed tissues, without considering biological and medical effects. This knowledge is of general interest for studies of nonthermic teratological or embryo-lethal effects of exposure to electromagnetic fields (EMFs). Throughout the entire 21 days of embryonic development, the mean temperature increases in the eggs during the exposure were found to be up to 0.25 degrees C for a power flux density of 1.25 mW/cm(2) and increased to 2.3 degrees C for 9.0 mW/cm(2). The corresponding maximum whole-body SARs for the embryos over the 21 days of embryonic development were 1.45 and 10.44 W/kg, respectively. At 0.75 mW/cm(2) (0.87 W/kg) the extent of the RF-field induced hyperthermia was within the measurement accuracy (+/-0.1 degrees C) of the temperature probes used in the tests. The field-induced temperature increase was greatest in the first week of incubation and was less pronounced in the last (third) week before hatching. In both the short- and the long-term exposures, the temperature of the exposed tissue and the amniotic fluid, respectively, reached its maximum (asymptotic) approximately 40-50 min after the RF field was switched on. After the field was switched off, the temperature inside the exposed eggs returned to its initial value within 40-50 min.

The avoidance of disruptions is essential for the next generation tokamaks. The dangerous consequences of disruptions are excessive heat loads, high forces, creation of high-energy runaway electrons, and a bad conditioning for the start of the following discharge. In order to mitigate these effects, a fast valve has been developed on TEXTOR with a response time to full opening of 1 ms after a trigger pulse. The fast injection of helium by such a valve suppresses runaway electron production and even removes them if present. The reaction time of the valve is fast enough to apply it even after the start of a disruption. The fast gas injection has been applied to a nearly stationary runaway discharge and it was successfully shown that the energetic electrons are quickly expelled.

A sensor to measure the intensity of power flux on the surface of food during microwave heating has been constructed, and measurements of the power flux intensity incident from the top surface of a cylindrical container were performed using the newly constructed sensor. The container was filled with water, and the power flux estimated from the temperature increase of the water after heating was confirmed to agree with the power flux measured using the sensor. Therefore, the ability of the sensor to measure the intensity of the incident power flux was confirmed. Next, the distribution of power flux intensity was measured in the radial direction for the cases of microwaves incident at the top surface, bottom surface, and top and bottom surfaces of the cylindrical container, respectively. This distribution of power flux intensity varies greatly depending on the heating conditions, but the temperature in the interior of food calculated using this value agreed almost with the observation results using a liquid crystal sheet.

The reciprocity theorem in Lyamshev’s formulation is used to derive a general symmetry relationship for the matrices of reflection coefficients in homogeneous media and one-dimensional waveguides. This relationship is shown to be equivalent to the normalization of the amplitudes by the cross power flux of the forward and backward waves. The relationship is valid for both propagating and evanescent waves, and all the symmetry relationships known from the literature represent its particular cases.

Models for the calculation of edge temperature gradients, of growth rates of edge thermal instabilities, and of the enhancement of edge transport coefficients due to thermal instability growth rates have been coupled. The composite model predicts the existence of threshold values of the edge power flux at which the edge transport coefficients sharply decrease and the edge temperature gradients sharply increase; i.e., an edge transport barrier forms. Predicted consequences of this transport barrier formation are found to be qualitatively consistent with phenomena observed experimentally in conjunction with the L–H (low-to-high) transition. It is suggested that this spontaneous formation of an edge transport barrier due to suppression of an edge thermal instability could be a trigger mechanism for the L–H transition in tokamaks.