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This paper is aimed to use a quantitative and visual method to evaluate the history, current and future of publications regarding fake news and rumors on social media. VOSviewer was used to identify and summarize the publications from Scopus and WoS from 2010 to 2020. Publication source, publication organization, authors, country, citation of articles, citation of country and organization were recorded and analyzed. Bibliometric maps of authorship, citation, co-citation and network of co-occurrence of keywords were drawn. 6354 articles and 33503 cited references were analyzed. The United States dominates the publications (1615, 25.4%) and citations (5867). University of Chinese Academic of Sciences (85) is the most productive organization. Loftus (26) is the most productive author. Memory & Cognition published the most papers about fake news and rumors. The latest keyword “machine learning” appeared in 2018 in 182 papers. Other relatively new keywords include “deep learning” “natural language processing” “social media platform” “fake news detection” “rumors detection” which appeared in 2018 in 98, 66, 63, 58, and 52 papers respectively. As for researchers and practitioners, this paper suggests an analysis of integrated visualization in terms of knowledge and innovation based on the area of fake news and rumors.

Squeezed state light is a fundamental resource for many quantum optics experiments. Important applications like quantum-enhanced magnetometer and quantum key distribution, require the squeezing level as high as possible. In balanced homodyne detection, the detector output is directly proportional to the noise of the squeezed beam. The detected quadrature is dependent on the relative phase between the squeezed beam and local oscillator. Here, we present a balanced homodyne detector (BHD) with independent phase control and noise detection branches. The independence between the phase control and noise detection branches is experimentally verified, the two branches are independently optimized according to the practical requirements. With the BHD, a bright squeezed light at 1550 nm with quantum noise reduction of 10.3 dB is directly detected. After stabilizing the relative phase between the squeezed states and local oscillator by the phase locking branch of the BHD, the fluctuation of the noise suppression is ±0.2 dB by 1-h testing time.

Due to the frequent occurrence of transient faults on overhead lines, the use of DC reclosing strategy can effectively improve its power supply reliability. However, when the DC grid coincides with a permanent fault, it will cause a secondary impact problem, endangering system operation and equipment safety. A fault location and reclosing scheme of DC distribution network based on parallel module is proposed. The parallel module consists of an energy absorption module and an energy storage module. The energy absorption module cooperates with the hybrid MMC to collect the residual energy of the current-limiting reactor and the line reactance. In addition, the energy storage module will also be connected to the absorption capacitor of the energy absorption module to charge it, so as to prevent the voltage traveling wave amplitude emitted by the absorption capacitor from being too low during the fault reclosing judgment, which will affect the judgment result. At the same time, using the principle of traveling wave ranging, the scheme also has the function of fault location. Finally, the simulation results prove that the method is effective and feasible.

The modular multilevel converter (MMC) is a promising topology in the field of DC distribution system. However, MMCs are vulnerable to the DC-line short-circuit faults. In this paper, an improved half-and-full-bridge MMC (IHF-MMC) topology is proposed. The transferring path of fault current in bridge arm is composed of a thyristor branch and current-transferring branch; on the other hand, the upper arm of phase C adopts unipolar-voltage full-bridge submodules instead of half-bridge submodules to absorb fault energy. After the DC fault occurs, the fault current is transferred to the upper arm of phase C, and then interrupted by the submodules through sequential coordination of two additional branches. The operation principle in different fault stages is analyzed in detail in this paper, and a ± 10kV/2.5MW simulation model is built in MATLAB/Simulink to verify the feasibility and effectiveness of the proposed topology.

The goal of a system restoration plan is to re-energize the entirety of the power system as quickly as possible. Identifying a cranking path at the 500 kV level can help to decrease the downtime after a blackout and to rapidly restore critical loads. Along the identified cranking path, energizing high voltage transmission lines requires capacitive/inductive reactive power compensation. Restoring loads and/or switching capacitors/inductors provide a certain amount of reactive power. However, manually switching these shunt compensation devices could cause transient/sustained over-voltages or dynamic instability. Instead of using fixed switched reactive power compensation, the use of Static Synchronous Compensators (STATCOMs) as a potential blackstart resource is considered to provide dynamic reactive power support. In this paper, the impact of a STATCOM on the restoration process is investigated. The study is conducted based on an identified cranking path at the 500 kV level in Dominion's system network. Simulation results in PSS/E and PSCAD show that implementing a STATCOM brings significant benefits to the system restoration process.

In the Data Technology (DT) era, data have become the most important means of production. With the rapid development of cloud computing, the database technology has become the most basic data technology facility. Especially, the Distributed Databases have been widely used to store and process large-scale data, which are applied in different scenarios than relational databases. In addition, blockchain technology has led to changes in decentralized architecture. The BigchainDB database is based on a distributed database with the features of blockchain. It has not only the advantages of distributed database, such as high throughput, low latency and easy expansion, but also has the characteristics of blockchain, such as decentralized control, tamper-proof and traceability. This paper mainly analyzes the comparison between the BigchainDB and other distributed databases in terms of execution performance. In practice, this paper focuses on the characteristics of BigchainDB, then compares the performance of creating and querying transactions between the BigchainDB and two important distributed databases: HadoopDB and Hive. The experiments in this paper show three things. Firstly, the BigchainDB is obviously better than HadoopDB and Hive in transaction creation. Secondly, the transaction query performance of the BigchainDB is one order higher than them. Thirdly, the BigchainDB is three orders of magnitude higher than them in fuzzy query performance. These results demonstrate that BigchainDB is significantly better than HadoopDB and Hive in both the performance of read and write.

In this paper, a new security and green communication scheme is proposed to the interference-alignment (IA) based networks. To achieve a secured communication, full-duplex receivers are utilized to transmit artificial noise (AN). Both the signals and the ANs are used to harvest energy to realize green communication. For these reasons, the feasible conditions of this scheme are analyzed first. Secondly, the average transmission rate, the secrecy performance and the harvested energy are investigated. Thirdly, an optimization scheme of simultaneous wireless information and power transfer (SWIPT) is given to optimize the information transmission and the energy harvesting efficiency. Meanwhile, an improved IA iteration algorithm is designed to eliminate both the AN and the interference. Furthermore, relay cooperation is considered and its system performance is analyzed. The simulations show that the target average transmission rate is not affected by AN, while the secrecy performance can be greatly improved. The energy harvesting efficiency is also better than the traditional schemes. As expected, the average transmission rate further is improved with the relay cooperation.

This paper presents an impedimetric biosensor for monitoring of crops using novel microneedle electrodes for minimally invasive, sensitive measurements, compatible with smart agriculture developments. The biosensor was fabricated through polydimethylsiloxane imprinting using a high-resolution 3D printed negative mold. This method allows for fabrication of tailored microneedles with heights up to $500\ \mu \mathrm{m}$ , required to penetrate through the epidermis of a leaf. The sensor was tested by recording the bioimpedance of Barely leaves and comparing its performance to conventional planar and needle electrodes. Furthermore, we present evidence of a diurnal pattern in plant bioimpedance that was detected by monitoring the leaf bioimpedance under controlled conditions.

A physical layer security encryption algorithm in OFDM-PON is proposed which combines three-dimensional constellation and chaotic mapping. The numerical results show that it has high security and better BER performance compared with traditional two-dimensional modulation.

The cluster synchronization of mutually coupled semiconductor lasers network with heterogeneous delays is systematically investigated, whose applicability is demonstrated by discussing two simple networks and a random network with Gaussian-distribution heterogeneous coupling delays.

The high penetration of large-scale renewable generations challenges the stability of power systems. It is likely to causes frequency fluctuations due to the intermittent nature. Demand Response (DR) has received much attention because it balances generation and demand with flexibility. Unlike the costly conventional spinning reserve, thermostatically controlled load (TCL) can be controlled to provide frequency regulation service with little impact on customer comfort. A progressive demand control strategy is proposed in this paper for the system frequency regulation. In particular, the state shift priority method is proposed to optimally control loads without compromising customer comfort. The operation-cycle based random recovery method is developed to mitigate the load rebound. Case studies are conducted to validate that TCLs can provide a fast and smooth frequency regulation via the proposed control strategy.

In order to effectively control vessel rudder under the random interference, this paper presented an innovative method based on extended linear-quadratic regulator (LQR) control method and adaptive genetic algorithm (AGA). With respect to the actual vessel navigation environment, the extended LQR control method is explored by using a series of calculus transformation under the random interference. Besides, the AGA is utilized to optimize two kinds of weighted matrices in Riccati differential equation. What's more, the crossover and mutation probabilities are adaptively computed in the process of AGA. The numeric simulation indicated that the proposed method can effectively control vessel rudder with the satisfactory robustness.

This paper proposes a novel method for fault classification in transmission lines. It uses the Average Wavelet Energy (AWE) to quantify high-frequency components during the fault period and determine the fault type by comparing values of AWE for different phases. The proposed method is tested with real fault events in the waveform library developed by Grid Protection Alliance (GPA) in partnership with Electric Power Research Institute (EPRI). The results show that the proposed method performs better than the traditional method implemented in openXDA in terms of the accuracy of fault type classification.

This paper presents the dynamic study of the Dominion Energy Virginia (DEV)'s System Restoration Plan (SRP) in the Real Time Digital Simulator (RTDS) environment. Firstly, dynamic models of DEV restoration paths are created and real-time simulations are performed to validate the feasibility of DEV's current SRP. Secondly, protection coordination and synchronization of islands have been studied and tested. The assessment results show that the relays operate reliably during the restoration process and islands can be successfully synchronized. The proposed restoration study and obtained simulation results can help system operators better understand the restoration goal and be prepared for unexpected blackout conditions.

A nearest group standardization kernel principal component analysis (NGS-KPCA) based monitoring method specifically designed for nonlinear multi-operation batch process is proposed in this paper. The key feature of the proposed method can deal with nonlinearity and non-Gaussian characteristics in the process. To start, phase partition is implemented according to operation. Then, k-means clustering algorithm produces an optimal ensemble clustering solution at each phase. Meanwhile, to deal with non-Gaussian characteristic produced by randomness and uncertainty of the operation, nearest group standardization (NGS) method is exploited to make the data belonging to the same cluster obey Gaussian distribution. To deal with nonlinear characteristic, KPCA is chosen to build monitoring model for each clustering. The proposed method is illustrated through the 120t ladle furnace (LF) steelmaking process. Simulation results have shown better performance than multiway kernel principal component analysis (MKPCA).

A bidirectional DC-DC converter based on single chip microcomputer (SCM) is designed by adopting bidirectional buck-boost topology instead of the traditional method of separately designing boost circuit and buck circuit. The converter is designed to achieve charging and discharging functions of five 18650 lithium-ion batteries. The main control chip of the converter is SCM STC12C5A60S2. The IR2104 half-bridge driver with bootstrap function is selected to drive MOSFET for stable turn-on and turn-off. The converter includes sampling circuit formed by the sampling resistor and the op amp op07 and display circuit formed by LCD1602, which can sample and display current and voltage in real time in both charging mode and discharging mode of the converter. In addition, the converter can control the current through keys. The overall system structure is simple, easy to control and low cost. The conversion efficiency is greatly improved using synchronous rectification. In the prototype test, the current fluctuation is small and the voltage stability is high. The designed converter is applied to a small DC motor drive circuit in a laboratory, the motor works well.

The understanding of power system characteristics and their impact on system behavior can lead to improved dynamic performances. Based on the Center of Inertia (COI) concept, this paper presents a practical study on the inertia distribution estimation, which can be used to both planning in long time scale and operation in short time scale, to meet with increasing renewable integration level in the future power system. Two indices are created to calculate the inertia distribution over the grid. Specifically, it is found that the proposed indices are highly related to the grid structure, and also they are affected by different parameters such as inertia constant, line parameters, terminal voltage set point of synchronous machines and models of exciters and governors. With these characteristics, the proposed indices have the potential to be applied on problems such as the placement of phasor measurement units or energy storage systems and generators coherency detection. Simulation results in a radial system, a meshed system and the IEEE 39-bus test system verify the characteristic of the proposed indices and show their potential applications in modern power systems.

Although connecting a microgrid to modern power systems can alleviate issues arising from a large penetration of distributed generation, it can also cause severe voltage instability problems. This paper presents an online method to analyze voltage security in a microgrid using convolutional neural networks. To transform the traditional voltage stability problem into a classification problem, three steps are considered: 1) creating data sets using offline simulation results; 2) training the model with dimensional reduction and convolutional neural networks; 3) testing the online data set and evaluating performance. A case study in the modified IEEE 14-bus system shows the accuracy of the proposed analysis method increases by 6% compared to back-propagation neural network and has better performance than decision tree and support vector machine. The proposed algorithm has great potential in future applications.

In this paper, a numerical model of halloysite nano-tubes (HNTs) modified surface plasmon resonance sensor is established and optimized. The simulations investigate the effect of HNTs size parameters on the SPR sensor performance. From this study we can find that the optimal design for halloysite modified SPR sensor.

In this paper, we consider a wireless powered communication (WPC) network consisting of one hybrid access point (H-AP) and K wireless nodes. The H-AP broadcasts wireless energy to nodes in the downlink and receives information from K nodes abided by TDMA protocol in the uplink. The wireless nodes have energy harvesting capabilities and can harvest energy from H-AP and other nodes in different assigned time slots. We propose two new schemes for the WPC network that perform energy harvesting among peer nodes. In the first scheme, each wireless node harvests energy from peer nodes transmitting in the previous time slots, while each wireless node harvests energy from all nodes in the second scheme. The maximization of the sum achievable throughput and the minimization of the required harvested energy are studied. An effective heuristic optimization algorithm is proposed to solve them. The contribution of this work includes the proposal of two new peer harvesting schemes, the formulation of two relevant optimizations and their solutions using heuristic optimization algorithm, which has better technical adaptability for solving complicated objective functions. Simulation results demonstrate the effectiveness of the proposed schemes in WPC networks.

This paper provides a method to evaluate the performance of contention resolution process existing in the uplink visible light communications. In such a system, multiple vehicles share a common communication channel to convey data packets to receivers mounted in the road lamps along urban streets. A finite state Markov chain model is established to investigate the steady state probability distribution of the system. Then, the average number of vehicles and the average sojourn time of each vehicle are obtained. The model can be used to compare different back off policies. Simulation results are compared with the theoretic results given by the method to show the accuracy of the theory.

An adaptive monitoring method is proposed to detect the fault in complex batch processes with multiple operations. The method firstly starts with limited modeling data types to build the model, and then updates initial model data by collecting new normal batches. The specific process includes stage division, the conversion of non-Gaussian to Gaussian of process data and the construction of clustering model. Then, an adaptive updating algorithm, based on the selection of clustering models and up-down monitoring method, is developed for model updating to collect additional information from new normal batch data. The proposed method is illustrated through the 120t ladle furnace (LF) steelmaking process. Simulation results have shown the effectiveness of the proposed approaches compared to MPCA.

The article presents a kind of small satellite disturbing loads full-physical simulation system which is used to deeply research and validate the control algorithms of orbit and attitude of small satellite under the effect of spacial disturbances. The system uses methods of air floating and hanging for gravity compensation of the five DOF air floating platform on which flexible solar wings have been installed. The main parts of the system have been designed and analyzed in the text. Finally, the feasibility of the system has been illustrated by the simulation that result from the combination of ANSYS and ADAMS softwares. The system proposed in this paper make it available that the satellite with flexible attachment as a whole be used for experiments under spacial disturbances on the ground, it is of great significance to suppress the vibration of flexible attachment and strengthen the stability of the position of satellite under spacial disturbances.

This paper present the preliminary experimental results of carbon nanotube(CNT) cold cathode arrays using thermal chemical vapor deposition (TCVD). The results of the field emission test show that the current density of carbon nanotube arrays can achieve 2.2A/cm2 with a total emission current of 17.2mA.

ZnO nanorods have been successfully grown on Ga doped (0, 1, 2, 3, 4, 5 wt%) ZnO seed layer by using simple hydrothermal method. The seed layer was coated on the substrate by using Dip coating technique. The effects of Ga doped seed layer on optical and structural morphology of ZnO nanorods are investigated in detail by using Fiel-demission scanning electron microscope (FESEM), X-ray diffraction (XRD) and Photo luminescence spectroscopy (PL). It has been observed that the Ga doped seed layer strongly affected the structural morphology of ZnO nanorods. XRD results show that all the samples have hexagonal wurtzite shape and [002] is preferred direction of growth. The intensity of (002) peak increases with increasing Ga concentration in seed layer indicating that the Ga doped seed layer has promoted growth of nanorods along [002]. SEM images show a decrease in diameter of ZnO nanorods with increasing Ga concentration in seed layer. The PL spectra of all the samples have two emission bands, UV and defect emission. UV emission shows a small blue shift with increasing Ga concentration in seed layer.

The oscillating wave test system (OWTS) which is similar to power frequency test system can be used to test the partial discharge of cable insulation defects. It is proved that using OWTS can bring many benefits such as it can make the test result be normative, and is not harmful to cable insulation which is totally suitable for field test. In order to study the PD characteristic of XLPE cable under oscillating wave voltage, four typical defects at different severity are designed to withstand the test voltage. The four defects are: A) the air-gap defect located at the cable joint, B) the cusp of semi-conducting layer, C) overly long or overly short overlap of stress cone joint, D) metal cusp at high potential. The experimental result shows that the partial discharge of different defects occurs at different phases which concentrate at 30°-70°, 220°-250°, while the number and quantity of discharge are quite different. The obvious differences between the four typical defects may lay a foundation for the further study on pattern recognition of XLPE cable. The typical damped oscillating voltage can be divided into 8 parts, the PD characteristic of XLPE cable under every part is also studied in this paper. After reading this paper we will have a deeper understanding of the PD excitation theory of oscillating wave.

The problem of identifying rumors is of practical importance especially in online social networks, since information can diffuse more rapidly and widely than the offline counterpart. In this paper, we identify characteristics of rumors by examining the following three aspects of diffusion: temporal, structural, and linguistic. For the temporal characteristics, we propose a new periodic time series model that considers daily and external shock cycles, where the model demonstrates that rumor likely have fluctuations over time. We also identify key structural and linguistic differences in the spread of rumors and non-rumors. Our selected features classify rumors with high precision and recall in the range of 87% to 92%, that is higher than other states of the arts on rumor classification.

A broadband pill-box window with sapphire piece for 0.14THz folded waveguide traveling wave tube is manufactured. Cold-test result shows the attenuation of the window is about 0.7dB during 0.13THz-0.15THz. Using the back-to-back method, the RF coupling system including pill-box and taper waveguide is test. The result shows that the VSWR is less than 1.2, which meets the practical requirements in 0.14THz folded waveguide TWT.

A design of CW 1W 0.14THz folded waveguide TWT is investigated. The electron beam tube is manufactured, and beam transmission of 82% for a 14.8mA beam at 21.5kV. The RF coupling system and attenuator are manufactured and tested. The test results showed good performance that can meet the practical requirements in folded waveguide TWT. The first prototype has been built. Latest test results will be provided if available.

Several studies on the prediction of the LC retention time of tryptic peptides have been applied on protein identification for the proteomic analyses. In this study a proteomic method was developed based on prediction of retention time of chromatography and mass to charge value. With the conversion of normalized elution time into predicted retention time, tryptic peptides of E. coli cytosol were analyzed by RPLC-ESI-MS/MS with the preferred precursor ion list generated from glycolysis/gluconeogenesis pathway. Totally 8 of the 25 targeted proteins were identified with the method of precursor ion selected MS/MS detection, comparing to the 5 proteins identified with automatic MS/MS detection. The new method shows improvement on both the number and the quality of the MS/MS detection of targeted peptides. The average absolute deviation of predicted RT and observed RT is 3.5 minutes, which indicates the acceptable application to the further proteomic analysis.

A simple method based on the physics characteristics to get the main parameters of folded waveguide traveling wave tube (TWT) circuit is present. Providing the operating frequency and beam voltage, we can obtain the initial structure parameters of the folded waveguide slow-wave structure. An 220GHz folded waveguide slow-wave structure is designed to verify this method. The cold characteristics including dispersion relation and interaction impedance are analyzed. The large signal performance of folded waveguide circuit is predicted by PIC code.

A 0.14 THz Watt level folded waveguide traveling wave tube was designed and optimized by CST simulation, including folded waveguide structure, electron gun, periodic permanent magnet, input-output structure, box window and beam-wave interactions. The design results showed over 6 Watt output power. In order to validate the flux rate of electrons, a flux tube was fabricated and tested. Results showed the flux rate was over 80%, preliminarily verifying the rationality of the design.

The formulas of output and ripple voltage from voltage multiplying rectifier are found in reference. The formulas are deduced on the condition of continuous simple harmonic waves. The corresponding formulas for input of pulse width modulating rectangle waves have not been found yet. In this study, pulse width modulating rectangle waves of high frequency are adopted as input of a voltage multiplying rectifier circuit, for validating the formulas. The effects of duty cycle parameter on the formulas were experimentally measured. Then new empirical formulas including duty cycle parameter are found. The applicability of new empirical formulas is also tested.

Looking into the history of those existed studies, advertising is normally seen either as a service of information which shifts the demand curve or as a signal which helps the consumers to form an expectation of the quality. So, in this paper my approach is a combination of the two. I will develop a new economic model, in which expected quality parameter is a function of the current advertised quality and the consumer's last period experience of the goods. The model is set in the infinite time context, in which each firm has to make its production and advertising strategy at the beginning of every period. Furthermore I will demonstrate some extensions to the basic model that lead to some revealing results relating the demand tendency to the advertising strategies.