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Recent studies of X-mode wave heating experiments observed by EISCAT (European Incoherent Scatter Scientific Association) UHF radar indicate that parametric instability (PI) can be excited unexpectedly. In this paper, we re-investigate the ionospheric heating experiment on October 21, 2012 in details. The observed HF-enhanced ion lines (HFILs) and HF-enhanced plasma lines (HFPLs) observed during the experiment presents dependence on the heating incidence angles. The observational evidence and numerical calculation that the parallel electric field of X-mode heating wave can exceed the PI excitation threshold at certain angles indicate the decisive role of parallel electric field for the PI excitation. The excited HFPLs and HFILs during X-mode heating cycles also present the evidence for the non-Maxwellian distribution of the electrons in the heated region.

Solar cell model parameters are of great significance in the study of solar cell fault model, power prediction and the maximum power point tracking. Therefore, it is very necessary to study an fast and accurate algorithm for solar cell model parameters identification. Based on characteristics of solar cell model, a solar cell parameters identification method based on particle swarm optimization (PSO) with adaptive elite mutation (AEM) is studied. Traditional evolutionary computation methods have the disadvantage of premature convergence, which will affect the accuracy of identification. In order to accelerate the searching speed, we select elite particles to replace inferior particles in the process of evolution. Meanwhile, adaptive mutation strategy can avoid the risk that particle swarm will lose its diversity and fall into local optimal solution. Combining elite particle and adaptive mutation strategy, we overcome contradiction between exploration and development of the optimization algorithm. The experimental results show that the particle swarm optimization with adaptive elite mutation (PSO-AEM) has a good effect and processing speed for identification of solar cell model parameters.

RPID5180397newnew. Thus, we conduct a statistical study of radiation belt dropouts. If PSD drops by factor >5 within a period less than 8 hours, we call it a dropout event. Based on 4 years of VAP data, we get the dropout distribution as a function of $\mu$ , K, and L* and the relationship with solar wind parameters and geomagnetic parameters. The results show that high L* dropouts cover wider $\mu$ , K range. The low L* dropouts mainly follow the influence regions due to EMIC wave. Few dropouts at low $\mu$ , K due to injection while there are many dropouts with low $\mu$ , high K, which is likely due to EMIC waves. Dropouts occurring without EMIC influence are company with stronger solar wind and magnetic activity.

W2018ATRASCHuang. In this paper, we report the simultaneous occurrence of two types of the whistler waves in the magnetotail reconnection diffusion region. The first type is observed in the pileup region of downstream and propagates away along the field lines to downstream, and is possibly generated by the electron temperature anisotropy at the magnetic equator. The second type is found around the separatrix region and propagates towards the X-line, and is possibly generated by the electron beam-driven whistler instability or Ccrenkov emission from electron phase-space holes. Our observations of two different types of whistler waves are well consistent with recent kinetic simulations, and suggest that the observed whistler waves are the consequences of magnetic reconnection. Moreover, we statistically investigate the whistler waves in the magnetotail reconnection region, and construct the global distribution and occurrence rate of the whistler waves based on the two-dimensional reconnection model. It is found that the occurrence rate of the whistler waves is large in the separatrix region ( $\vert B_{\text{x}}/B_{0}\vert >0.4$ ) and pileup region $(\vert B_{\text{x}}/B_{0}\vert 45^{\circ})$ , but very small in the X-line region. The statistical results are well consistent with the case study.

A Global Navigation Satellite System Reflectometry (GNSS-R) software receiver and its preliminary experimental results are presented in this paper. The antenna system, the radio frequency analog front-end, and the digital signal processing unit of this receiver are described in detail. With this software receiver, various algorithms and theoretical models can be verified for different remote sensing applications. Furthermore, preliminary experiments have been conducted to evaluate the performance of this receiver. The experimental results demonstrate that the Global Position System (GPS) satellites can be correctly acquired and tracked with this receiver, and that the calculated location parameters of the receiver, when four GPS satellites are tracked, are consistent with those provided by the Google map. In addition, when this receiver is used for the soil moisture retrieval, a measure error of about 5.79% can be achieved when compared with the measure results given by the soil moisture meter.

The troposphere and lower stratosphere (TLS) is an active region with atmospheric fluctuations. Some works concerning the dynamical and thermal structures and inertial gravity wave (IGW) activities in the TLS from the radiosonde observation have been reported. Wuhan atmosphere radio exploration (WARE) radar is the first Mesosphere-Stratosphere-Troposphere (MST) radar to have become operative in the mainland of China and is dedicated to real-time atmospheric observations. In this paper, some cases about IGWs detected from three-dimensional wind field data of the WARE radar are presented. The intrinsic frequencies, vertical wavelengths, horizontal wavelengths, vertical wavenumber spectra, energy density are calculated and analyzed. By calculating the vertical shear of horizontal and vertical wind, the Brunt-Vaisala frequency, and the Richardson number, the potential wave sources are also discussed.

The Wuhan atmosphere radio exploration (WARE) radar is one of the significant facilities of the Meridian Space Weather Monitoring Project of China and dedicated to real-time atmospheric observations. We compare the Wuhan MST radar wind data (3–25 km) with the simultaneous radiosonde data and the temperature data computed from NRLMSISE00 models. Our results show good agreement between the wind field data from Wuhan MST radar and from the GPS radiosonde. The tropopause heights determined by the three methods are close to each other. In terms of the structure constant of atmospheric refractive index Wuhan MST radar gives a height of 15–16.5 km, the GPS radiosonde temperature profile reads that of 16.5–17 km, and NRLMSISE00 modeling computes a value of 16.2 km. Current work indicates that the WAER radar is operative and its data are reliable.

The energetic electron population measured by multiple low-altitude POES satellites is used to infer whistlermode wave amplitudes using a physics-based inversion technique. We validate this technique by quantitatively analyzing a conjunction event between the Van Allen Probes and POES, and find that the inferred hiss wave amplitudes from POES electron measurements agree remarkably well with directly measured hiss waves amplitudes. We also use this technique to construct the global distribution of chorus wave intensity with extensive coverage over a broad L-MLT region during the 8–9 October 2012 storm and demonstrate that the inferred chorus wave amplitudes agree well with conjugate measurements of chorus wave amplitudes from the Van Allen Probes. The evolution of the whistler-mode wave intensity inferred from low-altitude electron measurements can provide real-time global estimates of the wave intensity, which cannot be obtained from in-situ wave measurements by equatorial satellites alone, but are crucial in quantifying radiation belt electron dynamics.

Coherent and narrow-band whistler-mode chorus waves with large amplitude have been observed in the radiation belt recently. These waves can cause strong nonlinear phase trapping and phase bunching effects, and the nonlinear resonant interaction are also related to excitation of whistler waves. In this study, we show a fact that, phase trapping effect always lead to electron successive acceleration and their pitch angle increase, while phase bunching tends to decceleration electrons and scatter them towards smaller pitch angle. This phenomenon can be genelized to any harmonic cyclotron resonance with oblique propagating chorus. A Hamiltonian system is constructed to visualize the phase motion, and to give an explaination for above phenomenon.

Local acceleration driven by whistler-mode chorus waves is suggested to be fundamentally important for accelerating seed electron population to ultra-relativistic energies in the outer radiation belt. In this study, we quantitatively evaluate chorus-driven electron acceleration during the 17 March 2013 storm, when Van Allen Probes observed very rapid electron acceleration up to multi MeV within ∼15 hours. A clear peak in electron phase space density observed at L∗ ∼ 4 indicates that the internal local acceleration process was operating. We construct the global distribution of chorus wave intensity from the low-altitude electron measurements by multiple POES satellites over a broad L-MLT region, which is used to simulate the radiation belt electron dynamics driven by chorus waves. Our simulation results show remarkable agreement with the observed electron PSD near its peak in timing, energy dependence, and pitch angle distribution, but other loss processes and radial diffusion may be required to explain the differences in observation and simulation at other locations away from the PSD peak. Our simulation results suggest that local acceleration by chorus waves is likely to be a robust and repetitive process and plays a critical role in accelerating radiation belt electrons from injected convective energies (∼ 100 keV) to ultra-relativistic energies (multi MeV).

Electrically-assisted manufacturing (EAM) is an emerging metal-manufacturing process which is promising in the automotive and aerospace industries. The process is based on the electroplastic effect that is supposed to reduce the stress needed in the forming and improve the ductility of the metal. In this paper, we develop an electroplastic measurement system to study the electroplastic effect of the A5083 aluminum alloy. And the effects of current density and the pulse width on the electroplasticity are preliminary investigated.

Based on finite embedded coordinate transformation method, a general transformation is given to design a compact waveguide coupler. It removes the limitation of material inhomogeneity and makes the coupler be more easily realized. It also offers us much freedom and flexibility in choosing the appropriate material parameters to practically implement the device. Full wave simulation based on the finite element method is performed to confirm the performance of the waveguide coupler.

By employing finite embedded coordinate transformation method, we propose a general transformation to design a highly directive horn antenna with homogeneous and anisotropic media. Different from the layered lens antenna, our antenna consists of four triangle regions made of homogeneous and anisotropic media, which greatly reduces the difficulty of practical realization. Full wave simulation based on finite element method is performed to validate the performance of the antenna.

This paper introduced the improvement and trend of home network. After studying the CEBus standard and technology methods of embedded system's Internet accessing, an embedded gateway based on ARM for the home network was designed. In the design, using SoC chip designed for this project to connect CEBus and the home appliances at home helps users control them easily and remotely through the Internet.