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Node localization has been one of the critical and significant research problems in wireless sensornetworks (WSN). The DV-Hop method determines the location of an unknown node based onthe anchor node location and the multi-hop forwarding principle, but the method falls far shortof satisfactory localization accuracy. Therefore, an improved Gray Wolf Optimizer (GWO) withcommunication strategy (IGWO-CS) is proposed in this paper. A convergence function based onthe sine function is proposed to eliminate the limitation of the convergence factor 𝑎 on the searchability of the GWO algorithm. A communication strategy based on Lévy flight is designed, which canimprove the efficiency of information interaction between wolves 𝛼, 𝛽 and 𝛿 while also improving thesearch accuracy and convergence speed. Extensive experimental results on 23 well-known benchmarkfunctions and unknown nodes location in WSN demonstrate the effectiveness of the proposed IGWO-CS method and also show sufficient competitiveness compared with other state-of-the-art algorithms,while the proposed IGWO-CS algorithm can achieve satisfactory performance in a short time.

Ionospheric Total Electron Content (TEC) is an important parameter for space weather research. Based on GNSS data from China Crustal Movement Observation Network (CMONOC) and International Reference Ionosphere (IRI) model, we develop a TEC model in China and adjacent region (15°N − 55°N and 70°E − 140°E) with spatial and temporal resolution of 1°×1° and 30 min. This model is developed by using Kalman filter algorithm. In the covariance matrix, the monthly average is used as the background reference field of the error matrix, and the spatial variation of TEC deviating from the reference background field in each day of the month is statistically analyzed. The assimilative results show that the data assimilation method can effectively combine the observational data with the background model to make up for the temporal and spatial limitations of the observations. In addition, the data assimilation algorithm can produce a short-term TEC forecast. The predicted results are consistent to the observations in the early stages of the forecast. With the increase of predicting time, the impact of the observational data on the predicted results weakens. The results become more biased toward the background data, and the biases can be corrected by observation data.

Scientists investigating the coupling between the lithosphere, atmosphere, and ionosphere (LAI) require multiple instruments installed on and near the Earth’s surface and aboard satellites orbiting the Earth. However, challenges always occur owing to a lack of observation data from other monitoring instruments and/or the distance between distinct instruments. A novel system for monitoring vibrations and perturbations in the LAI (MVP–LAI) was established in the countryside of Leshan City, Sichuan Province, China, in June 2021. Twelve different types of instruments with 18 devices were set within an area of 50 m × 50 m. The other two were installed approximately 20 km away to avoid interference. These instruments routinely monitor the changes in at least 14 geophysical parameters with short sampling intervals, available for capturing waves propagating from the subsurface to the ionosphere. Once the observations retrieved from the China Seismo-Electromagnetic Satellite and the radio occultation are integrated, the monitoring of vibrations and perturbations can reach ~ 800 km above the Earth’s surface. The system is mainly operated by the China University of Geoscience (Wuhan), China and will officially start functioning in September 2021. All the efforts benefit the investigation of the causal mechanisms of LAI coupling and expose the potential sources of vibrations and perturbations, incorporating observations from other spheres.

The end sulfydryl group functionalized Fe3O4@SiO2 (Fe3O4@SiO2-SH) nanoparticles were synthesized with 3-mercaptopropionic acid as a sensitive and efficient chemosensor for the removal of heavy metal ions, in which branched polyethylenimine was used to provide numerous sites for the modification with 3-mercaptopropionic acid in order to increase the amount of sulfydryl group on the Fe3O4@SiO2 surface. The magnetic Fe3O4@SiO2-SH nanoparticles displayed the maximum adsorption efficiency for Pb2+ (257.1 mg/g) at room temperature without pH pre-adjustments. Moreover, Fe3O4@SiO2-SH nanoparticles also had desirable capturing abilities towards Cu2+ (90.3%), Hg2+ (89.8%), Ag+ (84.1%) and Cd2+ (78.6%) when their initial concentrations were 200 mg/L.

Convection is an important source to excite gravity waves. But the activity characteristics of the convection are hard to research, because it is transient and localized. This paper utilizes the five beams operated by mesosphere–stratosphere–troposphere radar to study the radial movements before, during, and after the small-scale convection. The Doppler spectra of radar echoes during the convection are evidently different from that in the clear weather. The strong updrafts ( $\sim 5.1\,\,\text {m}\cdot \text {s}^{-1}$ ) and downdrafts ( $\sim 2.4\,\,\text {m}\cdot \text {s}^{-1}$ ) make the turbulent motion compositions more complex, so the radial Doppler velocity and Doppler widths of five beams are almost significantly different at the same height. The characteristics of gravity waves are detected by using the quasi-monochromatic inertia gravity wave model. The results indicate that: 1) the kinetic energies of the IGWs during the convection are more powerful than that before and after the convection, and the propagation directions of the IGWs during the convection are also different to that before and after the convection and 2) the propagation parameters of the IGWs in different regions are also different during the convection, which means that the cold zone is at south and the warm zone is at north for this convection case.

By using the 2002–2016 dataset of COSMIC, CHAMP and GRACE radio occultation (RO) and TIMED/TIDI, we investigate the morphology of global sporadic E (ES) layers and its relation with wind shear. The occurrence rate of ES layers depends on temporal and spatial variation. The occurrence rate of ES layers has a maximum at around 103 km in middle latitude regions in summer hemisphere. The results show that the global distribution of ES layers is relatively consistent with the wind shear distribution. The height-local time distribution of ES layers occurrences are primary modulated by diurnal and semidiurnal atmospheric tides. However, the distribution of ES layers occurrence rate cannot be explained completely according to the wind shear theory, especially at equatorial and auroral regions. More observations are required to further investigate the formation of ES layers and its relation with wind shear.

Very high frequency (VHF) radar can not only get higher resolution atmospheric three-dimensional (3D) wind fields, but also observe complex atmospheric echoes in the rainfall environment. This paper uses Chung-Li VHF Radar with five beams to observe the frontal rainfall and explore the physical process of atmospheric rainfall. The observed results indicate: 1) the height of bright band is at about 3.5 km with the thickness about 0.5 km and is lower about 0.5 km than the zero isotherm observed by the radiosonde. 2) When the strong updraft exists, the rainfall echoes will weaken and the bright band will be indistinct; when the downdraught exists, the rainfall echoes will strengthen and the bright band will be distinct. 3) The thickness of melting layer is about 1 km, the velocity of rainfall particles in the melting layer is smaller than that below it but spectral width is the opposite. The aspect sensitivity calculated from five beams shows that the radar rainfall echoes mainly come from the anisotropic scattering below the melting layer but isotropic scattering in the melting layer.

A statistical analysis of sporadic E layer recorded from September 2011 to September 2015 at four Chinese ionospheric sounding stations of Mohe (122.37°E, 53.50°N), Beijing (116.25°E, 40.25°N), Wuhan (114.61°E, 30.53°N), and Hainan (109.13°E, 19.52°N) are presented to investigate the characteristics of sporadic E layer at the middle latitudes over China. The occurrence of the sporadic E layer in mid-latitude China region shows strong dependence on local time and season, consistent with previous studies. The occurrence of the mid-latitude sporadic E layer is prominent at local daytime in summer season. The results also reveal that the post-sunset sporadic E layer is statistically pronounced in mid-latitude China region, possibly related to the nighttime mid-latitude E region irregularities. The mid-latitude sporadic E layer is modulated by atmospheric tidal waves and planetary waves at different latitudes. The occurrence of the mid-latitude sporadic E layer also tends to increase with the level of geomagnetic activity on basis of both the statistical analysis and case study.

In this paper, the observation data of the Wuhan MST radar in the whole 2012 are used to make a statistical analysis on the low stratospheric and troposphere tidal waves. The results show that: (1) the diurnal tide is the strongest and most of the time at low levels of Sunday tide is stronger than the high tide of Sunday. (2) the amplitude of the tidal wave is not modulated by the fluctuation with a smaller time scale than their periods, and only these waves with a longer time scale than their periods can affect the variation of the amplitude of the tidal waves.

This paper focuses on electricity load forecasting of large-scale electrical grid. The smart grid is developing rapidly in the half-decade; it becomes the new goal of electricity industrial construction. Stability, reliable, flexible and self-cure are the main electricity characters, and accuracy forecasting power load play an important role in this process of smart construction. In this paper, we take Estonia country power load as a case, convert the load data to supervised learning data, and then use long short-term memory (LSTM) recurrent network do training model and forecasting. The experiment demonstrates the method is efficient, and compared with support vector regressive (SVR), LSTM could extract the feature of power load better accuracy and obtain the better performance of forecasting. The result can help national grid planning.

Wuhan atmosphere radio exploration (WARE) radar is the first mesosphere-stratosphere-troposphere radar to have become operative in the mainland of China and is dedicated to real-time atmospheric observations. Based on the WARE radar data collected for the period from September 2011 to February 2013, 2666 downward and 1735 upward inertia gravity waves (IGWs) are identified from three-dimensional (3-D) wind fields observed in the troposphere and subsequently analyzed in a statistical manner. Wave characteristics including intrinsic frequencies, vertical wavelengths, horizontal wavelengths, vertical wave number spectra, energy density spectra, and wave sources are investigated using a combination of the Lomb-Scargle spectral analysis, the quasi-monochromatic gravity waves model, and the hodograph method. Our results demonstrate that the characteristic parameters of upward and downward tropospheric IGWs are not significantly different. These results indicate that the tropospheric IGWs parameters are not directly correlated with propagation directions. Combining with the information of statistical 3-D wind field and some climatic characteristics of Hubei Province, atmospheric moist convection will contribute most in summer, whereas jet/front systems will contribute most in winter. One may expect seasonal variations to be tied to the varying importance of these sources.

The solar and wind energy are the great sources to our world because they are clear and unexhausted. In recent decades so many generation farms had been constructed rapidly all over the world. How to evaluate the investment performance and make a better planning for a long term have becoming an important issue. In this paper we discuss and analysis these questions based on actual data take Germany as a case. We discuss the solar and wind energy utilization situation, the generating electricity ratio, and investigate the rules of solar and wind generation, address an approach to adjust solar generations and wind to take advantage of them. Present a scenario of mid-long term planning in power grid, in order to make use of renewable energy, especially solar and wind sources to satisfy the demand of energy for our society development rapidly.

The recently constructed Wuhan Atmospheric Radio Exploration (WARE) radar is the first mesosphere-stratosphere-troposphere (MST) radar in the mainland of China, located at Chongyang, Hubei Province (114°8'8'' E, 29°31'58'' N, ∼ 23° geomagnetic latitude). WARE radar has a capability of probing the structure and dynamics of the atmosphere at the altitudes from 3 to 100 km (excluding 25–60 km). With fine temporal and spatial resolution, WARE radar provides an outstanding opportunity for the first time to extensively and intensively investigate various atmospheric phenomena at the regions of mid-latitude China. In this paper, we present the main configuration and technical specifications of WARE radar system. For the first time, we also report some initial results obtained by the WARE radar: (1) wind field observations from 69 to 85 km and from 3.2 to 16.9 km together with their comparisons with the rawinsonde results, (2) tropopause heights determined by radar echo power and comparisons between radar tropopause and rawinsonde tropopause, (3) atmospheric gravity waves in the troposphere with the wave length and propagation direction analyzed using the hodograph method, (4) aspect sensitivity of echo power at six specified heights in the troposphere and stratosphere, and (5) diurnal and semi-diurnal tides at the tropospheric and low stratospheric heights analyzed by the Lomb–Scargle periodogram method.

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.