bluuebunny/crossref_metadata_2025 huggingface dataset:
Reaction Model and Heat Release for Low-Temperature Ignition of Isobutanol
Authors: Díaz-González M , Prince J C , Castellanos-Onorio O
Published: April 2022

This research presents the study of heat release in the iso-butanol ignition process at temperatures T < 900 K, applying low-temperature chemistry and starting from a proposed kinetic scheme of 12 elementary reaction stages. A numerical analysis of the thermal energy release available for ignition is developed, where the formation of aldehydes is important in this combustion phenomenon. The low temperature kinetics for this alcohol were found to be unable to maintain the reactivity of the system. The OHs generated by low temperature chemistry react mainly to produce iso-butanal aldehyde instead of consuming the main fuel which inhibits NTC (Negative Temperature Coefficient) behaviour. To maintain the reactivity of the system, the reaction pathways of hydrogen peroxide H2O2 (HO2→H2O2→OH) are added, obtaining a short kinetic mechanism of 14 reactions that generates a good fit for the experimental developments of ignition time at lower temperatures. of 1000 K.
Research on Protection Effects of Drainage Line on Secondary Cable in Substation
Authors: Gong Lele , Shen Chen , Fan Lintao , Cai Xinjing
Published: April 2022

Ensuring the operation safety of secondary cable is an important part of substation grounding system design. In some cases with high soil resistivity and large grounding grid, the safety of secondary cable can not be guaranteed by optimizing the design of grounding grid. This paper compares the core-to-skin potential difference and the shielding layer current of secondary cable with or without drainage line. It is shown that the drainage lines, which are laid in parallel with the secondary cable, can significantly reduce the core-to-skin potential difference and shielding layer current of secondary cable during power frequency short-circuit and lightning stroke. When the radius of the drainage line reaches 5mm, core-to-skin potential difference and shielding layer current of secondary cable will be reduced to 1/3 of those when it is not laid.
Influence of Charge Injection on Dynamic Characteristics of Space Charge in Polymer Thin Films Under AC Stress
Authors: Deng Chuanhai , Wang Han , Xiao Jieping , Liu Yuqi
Published: April 2022

At present, most studies focused on the formation and accumulation of space charge under DC stress, relatively few studies focused on dynamic characteristics of space charge under AC stress. However, space charge dynamics under AC stress is of significance because the majorities of polymer insulation systems are subjected to AC voltage. In order to study the effect of charge injection mechanism from the electrodes on dynamic characteristics of space charge under AC stress, bipolar charge transport model are used to simulate the current density, electroluminescence intensity, space charge densities in polyethylene with different charge injection mechanisms. It is found that the simulated electroluminescence intensity and space charge densities under AC stress assuming the exponential functional approximation injection is more reasonable than those assuming the Schottky injection.
Lever-Based Semiactive Inerter and Its Application in Vibration Absorbers
Authors: Wu X C , Cui K K , Xiong Y Q , Chen M Z Q
Published: April 2022

In this paper, a lever structure is proposed to enlarge the range of inertances of existing semiactive inerters. A semiactive inerter with the lever structure would be called lever-based semiactive inerter. The transmission ratio of the lever-based semiactive inerter can be changed by setting a different ratio of the arm of force of the lever, and then the range of inertance of the lever-based semiactive inerter can be enlarged. This paper also presents the mechanical model of the proposed lever-based semiactive inerter. The lever-based semiactive inerter is applied to an adaptive tuned vibration absorber. The frequency-tracker-based control algorithm is derived to maximize vibration reduction of the absorber. It can be shown that the vibration absorber with the lever-based semiactive inerter can adapt to a broader range of frequencies of vibration compared with that of the classical semiactive inerter.
Crowd Stability Analysis Based on Pedestrian Abnormal Postures
Authors: Zhu Wenjie , Zhao Rongyong , Zhang Hao , Jia Ping , Wang Yan , Li Cuiling , Ma Yunlong
Published: April 2022

Abnormal behaviors of pedestrians in crowd gathering public places are important factors affecting the stability of crowd flow. Pedestrian abnormal postures are important manifestation of abnormal behaviors, which often leads to local turbulence, disturbance and density-speed fluctuations. It is urgent to discover the disturbance mechanism of abnormal pedestrian posture on the stability of crowd flow. This study intends to establish machine vision, kinematics, dynamic models and crowd confluence dynamic models for typical abnormal pedestrian postures in public places. We mainly use computer vision related technology based to recognize abnormal postures of pedestrians in videos, constructs a network matrix of key posture nodes, and studys the kinematics characteristics of abnormal posture nodes. Considering the number of pedestrians and the characteristics of the architectural scenes, we design a workflow to select the appropriate macro or micro dynamic model to build the crowd flow model. To validate the propuesd model, case in Shanghai Hongqiao railway station is studied.
Attribute Reduction Based on the Fuzzy Rough Set with Lukasiewicz Implication Operator
Authors: Ma Yuanhong , Zhong Yu , Zou Jietao
Published: April 2022

Attribute reduction is a common technique and has made breakthroughs in many aspects. One of the major development directions of attribute reduction is the extended fuzzy rough set models, which is embodied in the selection of fuzzy similarity relations and operators, eventually the derived membership functions. In view of the relatively simple selection of implication operators in related research, this article discusses the impact of different implication operators in the fuzzy rough sets. Secondly, the rough set model that relies on Lukasiewicz implication operator is further improved, and the proof of the closure of the new operator on the positive field is given. Finally, a new algorithm is given, and experiments are designed to prove the feasibility of the new algorithm based on eight public data sets.
Synthetic Evaluation on the Potential Ecological Risks of Heavy Metal Pollution in Sediments in the Sea near Bohe Port of Maoming
Authors: Zhu Xiaoping , Chen Wenlong , Wang Jianguo , Guo Wei , Lei Liehui , Liu Yisi , Ye Weicong , Chen Xiaoxuan
Published: April 2022

The pollution index method and Hakanson potential ecological risk index method were used to study and analyze the pollution factors (Hg, Cu, Pb, Zn, Cd, As, Cr) in surface sediments of the sea near Bohe Port of Maoming. The results show that the overall contamination level and potential ecological risk of typical pollutants are at the low level in this sea area. The sequence of the pollution degree of heavy metals in surface sediments is As> Cr >Zn> Hg>Cu>Pb>Cd; and the potential ecological risk sequence is Hg>As>Cd>Cu>Pb>Cr >Zn. Hg is the major factor of potential ecological risk in surface sediments of this sea area.
Analysis on Cracking of a Pipeline Steel Pipe during Hydraulic Burst Test
Authors: Luo Huaquan , Yang Lineng , Chen Xiaoli
Published: April 2022

Through macroscopic and microcosmic analysis of fracture, chemical composition analysis, fracture microscopic analysis and other methods, the causes of longitudinal and transverse fracture (only longitudinal cracking commonly through thousands of columns) in hydraulic burst test of L360M LSAW pipe were analyzed. Test results showed that the causes of transverse cracks in the steel pipe were the poor toughness of the pipe material which was related to the serious ferrite-pearlite banded structure. The serious band structure in the pipe was related to the high manganese content in the steel, which leaded to manganese segregation. We can use some measures to reduce the banded structure including controlling the element manganese content reasonably, reducing the final rolling temperature, controlling cooling rate and micro alloying.
Analysis of Onshore and Offshore Soils in the Lower Xiangjiang River
Authors: Zhou Yu-feng , Zhang Nan , Han Weizheng , Li Qing-qing , Cheng-ya  , Li Na
Published: April 2022

The soil on the west bank of the Xiangjiang River in the main urban area of Changsha, Hunan Province is referred to as shore soil, and the soil on the mid-levels of the Yuelu Mountains in Changsha is referred to as offshore soil. To stabilise the heavy metals in the soils, which do not readily migrate by pyrolysis, these soil samples were heated at 450°C for 3 hours in a muffle furnace and removed after natural cooling. These heated and stabilised soils were analysed by inductively coupled plasma emission spectrometry (ICP-OES), scanning electron microscopy (EMS) and XRD diffractometry respectively. It can be found that: (1) There is a difference in the heavy metal content between the shoreline soil and the offshore soil of the Xiangjiang River. (2) The scanning electron microscope shows that the microstructure of the soil is altered by prolonged river water infiltration and washing. (3) Both onshore and offshore soils are a mixture of crystalline and non-crystalline materials, with less non-crystalline material in the onshore soil compared to the offshore soil. (4) The main crystalline material in both onshore and offshore soils is SiO2.(5) Soil samples containing metallic elements are mostly in non-crystalline form.
Research on the Physicochemical Properties of Fine Particulate Matter in Changchun, Northeast China
Authors: Zhou Yu-feng , Han Weizheng , Zhang Nan , Qing-qing Li , Cheng-ya  , Zhang Dan , Li Na
Published: April 2022

Objective: Air particulate matter concentrations in Changchun City, Jilin Province, may change around the autumn heating day. The aim of this study was to provide data references for environmental protection, detection and regulation in Changchun. Methods: Atmospheric particulate matter samples were collected using an airborne particulate matter sampler on the roof top of the Civil Engineering Teaching Hall on the campus of Jilin University of Construction; free settling dust of Atmospheric particulate matter was collected using metal trays. Atmospheric particulate matter concentrations were analysed by manual detection methods (weight method), carbonaceous fractions by total organic carbon analyser, and atmospheric fallout material composition and crystal structure by XRD diffractometer. The physicochemical properties of fine particulate matter around the autumn heating day in Changchun were investigated. Conclusions: (1) The daily average concentrations of various types of atmospheric particulate matter PM1, PM2.5 and PM10 generally increased after the start of the heating period. However, air quality is influenced by a combination of meteorological factors, of which emissions of air pollutants from urban heat generating plants during the heating period is only one aspect. So there is a situation where the average daily concentration of atmospheric particulate matter is lower after heating than before. (2) Analysis of the atmospheric its particulate matter PM2.5 samples collected around the heating day showed that the daily average concentrations of organic carbon (OC) and elemental carbon (EC) of atmospheric its particulate matter PM2.5 increased significantly after the heating day. (3) There was no significant difference in the main components of atmospheric dust fall before and after the heating day in Changchun, with the main components being crystalline SiO2 and a small Number of impurities.
QoS Assessment for Video and Audio Data based on a Testbed for Multimedia Wireless ad Hoc Networks
Authors: Anh Ngo Hai , Giang Pham Thanh
Published: April 2022

Currently, with the fast modernization of wireless networking technologies as well as the very complex needs of the network users, multimedia data takes for a large proportion in the types of network services, this type of data requires Quality of Service (QoS) differs from traditional data, by ensuring the listening and viewing elements of the user. In this paper, we analyse the effect of video and voice data on QoS of wireless network services based on the establishment of an experimental evaluation (emulation) system or testbed, thereby providing empirical analysis on the effect of multimedia data on mobile wireless QoS.
Impact of Intelligently-configured Cloud Service Capability for High Manufacturing Performance via a Multi-agent Model
Authors: Zheng Xin , Zhang Xiaodong , Lei Shaojuan
Published: April 2022

In order to discover the impact of intelligently-configured cloud service capacity for high performance, this paper proposes a multi-agent model that simulates industrial manufacturing activities via a cloud platform via XaaS (Anything-as-a-Service). The multi-agent model is adopted to simulate cloud manufacturing based on two groups of service providers with different configurations on service capability. The capability configurations have been conducted against 8 kinds of service demands with the aim at the impact on how to configure cloud service capacity for high performance. Furthermore, the intelligent configuration is proved with high relevance of better task responses to diverse service demands. In the meantime, the intelligent configuration is also characterized with flexible adaptability and service balance. As a result, service performance has been effectively improved and significantly optimized by adjusting the service sequence within a given period that reduces the switch frequency among diverse service types.
Model to Relationship the Speed of Hand Movements with the SEMG Signals from the Forearm
Authors: Sandoval-Rodriguez C L , Pita-Mejia A C , Villamizar-Mejia R , Tarazona-Romero B E , Lengerke-Perez Omar
Published: April 2022

Various previous works have sought to achieve hand prostheses with natural movements. It has been employed tools to recognize patterns of surface electromyographic signals associated with each move. Although many successful studies classify some types of hand movements with high performance, the results show that the speed and strength must be analyzed so that the resulting moves are like those of a natural hand. This study evaluates 23 healthy subjects at two different speeds and six types of movements (pronation, supination, ulnar deviation, radial deviation, flexion, and extension -276 records of SEMG and Velocity). The objective was to obtain a model (transfer function) that would allow the relation of the velocity profiles with the tone of the forearm SEMG signals. The results show models with an average RMSE of 18.55% for slow movements using low-order systems (2). The parameters of the models between subjects are very different, with high coefficients of variation and standard deviations, which implies that the fitting must be for each subject.
Features of the Formation of an “Information Flight Model” by Simulators of an Aviation Simulator
Authors: Roganov Vladimir , Chetvergova Maria , Remontova Lyudmila
Published: April 2022

Currently, flight simulators are being developed to train pilots in the professional piloting of an aircraft in “special cases of flight”. This is due to the need to teach the pilot the professional skills of piloting an aircraft in situations that are dangerous to reproduce in real flight. An aviation simulator is a combination of several imitators that simulate information about the behavior of all units of the aircraft and information about the interaction of the airframe of the aircraft with the atmosphere, depending on the control actions transmitted by the pilot through the simulators of the flight simulator controls. It is believed that the quality of information models synthesized by simulators is determined by the capabilities of modern software and hardware elements, or used mechanical units. It is impossible to create a complete model of any node; therefore, each imitator synthesizes, in addition to true information, additional false information. It is impossible to exclude false information. Therefore, when developing aviation simulators, a number of training situations are determined. The article discusses the features of assessing the degree of participation of information from two groups imitators in the formation of the components of a cognitive model that allows a pilot to fly an aircraft.
Research on Advanced Driver Assistance System Oriented Height Distortion Hierarchical Shape Point Matching and Interpolation Algorithm
Authors: Zhang Kai , Wang Weili
Published: April 2022

In order to meet the needs of matching Advanced Driver Assistance System (ADAS) map elevation data to ordinary map shape points, we propose a hierarchical point-position matching algorithm and interpolation algorithm. The main work is as follows: (1) Under the premise of considering different road scenes, the characteristics of road shape points on the ADAS map and road shape points on an ordinary map are fully analyzed, and elevation data are matched to road shape points on an ordinary map through graded matching calculation to obtain more accurate elevation value. (2) For the road shape points on the ordinary precision map which does not match the appropriate elevation value, the more accurate results are calculated by interpolation method according to the elevation value of the front and back order points, so as to achieve the coverage of the road elevation value on the ordinary map. Take the road of Beijing map as the test sample, and the results show that the algorithm is reasonable and effective through statistics and sampling analysis. In terms of the verification of matching coverage, the ADAS map road network points are successfully obtained or calculated the effective elevation value of 976835 points, with a matching rate of over 99.99% after the hierarchical point-position matching algorithm and interpolation calculation algorithm. Furthermore, the results of the practical application of feedback also show that the algorithm can satisfy vehicles daily for ADAS basic function application.
Collision Avoidance Strategy for Self-Driving Vehicles Based on Drivers and Environmental Factors
Authors: Zhao Yibing , Li Bin , Xiang Xiumei , Guo Lie
Published: April 2022

In order to enhance the driving safety, various driving assistant systems are gradually developed and widely used. Based on the safe distance model related to the braking process, one warning/dangerous critical distance model for longitudinal control is proposed in this paper, considering the driver’s style and environment factors. The variable driver response time is obtained by employing fuzzy control theory. The author then establishes the vehicle dynamics model and its inverse model. Through the relative distance error and relative speed error, the upper controller is designed to obtain the expected acceleration based on sliding mode control, and the lower controller based on PID control is designed to track the acceleration. In order to solve the chattering problem of sliding mode controller, the author proposes variable gain coefficient control method. The fixed gain parameter in the expected acceleration formula is related to the negative exponential correlation formula, which can effectively depress the chattering of the expected acceleration. Finally, the author uses CarSim and Simulink to establish a co-simulation model of the collision avoidance warning system, and designs the test simulation conditions for typical traffic test scenarios to verify the control algorithm effectiveness.
Method for Day-head Operations of a Large Hydropower Plant Considering Peak-shaving Demands of Multiple Provincial Power Grids
Authors: Liu Shuangquan , Zhao Zhenyu , Shen Jianjian , Zhang Ran , Wang Yue
Published: April 2022

Large hydropower plants in China are usually required to transmit power to multiple provinces and meet their complex peak-shaving demands. How to model and solve this problem is challenging. Based on a Hydropower Project in southwest China, this study proposed a method for day-head operations of large hydropower plant considering peak-shaving demands of two provincial power grids. A short-term peak-shaving model for multiple power grids is constructed, which takes the minimum sum of the squares of the remaining loads of each power grid. This model considers complex constraints such as the operation of hydropower plants and the requirements of power transmission. The multi-objective optimization is transformed into a single-objective problem and solved by a group search algorithm based on the genetic algorithm. Two cases which respectively consider different loads and objective weights are presented to test the model. It is found that the large hydropower plant can simultaneously respond to different peak loads for multiple power grids. It should be also noted that different objective weights may have a significant effect on peak-shaving results.
Observation of X-rays during heating a pyroelectric crystal by an infrared laser
Authors: Nazhmudinov R M , Kubankin A S , Oleinik A N , Klenin A A
Published: April 2022

A pyroelectric X-ray source is proposed, in which a lithium tantalate crystal is heated by an infrared laser with a wavelength of 10.6 μm. X-ray spectra measured during irradiation of the crystal with infrared radiation and during natural cooling of the crystal include characteristic X-ray radiation of atoms contained in the structural parts of the source, as well as bremsstrahlung of electrons with energies above 50 keV. An 8 mm sodium chloride window was used to inject 64 W infrared radiation into a vacuum chamber with the pyroelectric crystal installed.
Environmentally friendly synthesis of silicon dioxide nanoparticles and their application for the removal of emerging contaminants in aqueous media
Authors: Tejedor Jennifer , Guerrero Victor H. , Vizuete Karla , Debut Alexis
Published: April 2022

The highly detrimental potential effects that emerging contaminants have for the environment and human health demand the development of sustainable technologies to eliminate these pollutants. In this work, an eco-friendly approach was followed to synthesize S1O2 nanoparticles to be used to remove caffeine and triclosan from synthetic waters. Rice husk was the precursor used, which was subjected to acid leaching treatments using acetic and oxalic acids, and pyrolysis for 2 h at 700 °C. The resulting powders were characterized by X-ray diffraction, Raman and infrared spectroscopies, the Brunauer-Emmett-Teller method, and scanning and transmission electron microscopy. The particles synthesized were amorphous, had an average size between 4.6 and 9.6 nm, and specific surface areas between 208 and 223 m2/g. The adsorptive performance of the nanosilica obtained using acetic acid was studied by batch tests. The optimum dosage, maximum removal efficiencies and maximum adsorption capacities were 8 g/L, 76%, and 2.74 mg/g, and 24 g/L, 48%, and 0.75 mg/g for triclosan and caffeine, respectively. The data collected fitted the Sips isotherm model, and the pseudo-second and -first order kinetics models, for triclosan and caffeine, respectively. The promising results obtained open the possibility of using the synthesized nanomaterials for removing a variety of toxic and recalcitrant pollutants.
On the low star formation rate in Saggitarius C
Authors: Karen Martínez A. , López Ericson
Published: April 2022

The Central Molecular Zone (CMZ) contains approximately 10% of the total molecular gas in the Galaxy concentrated in turbulent and dense molecular clouds. The fact that the star formation rate is low in CMZ is an open question, since there is a large amount of dense gas clouds where star formation could have started. Sagittarius (Sgr) C is the only known star formation region located in the western side of the CMZ. The main goal of our study was to find out the dominant physical conditions of Sgr C and how they could affect the process of star formation in the CMZ. We studied the dust emission toward Sgr C using infrared data. Using radio data we also studied the kinematic temperature, star formation rate surface density and cloud morphology of Sgr C. Our study showed a dust temperature T
d
of approximately 19 K toward Sgr C, which is in agreement with values estimated in other clouds of the CMZ and the Galactic plane. A high kinetic temperature higher than 58 K was determined toward Sgr C, which plays an important role in the cloud fragmentation and subsequent star formation. Based on our radio analysis we found a star formation rate surface density of ∑
SFR
= 4 × 10-3
M
⊙yr-1
kpc
-2 which is lower than in others molecular clouds of the Galaxy. Finally, the HCO
+ emission reveals the presence of cavities and shells in regions where there is no evidence of star formation. These shells could be related to cloud shocks believed to take place in Sgr C. It is thought that cloud shocks may have triggered star formation in other sites of the Galaxy, which is not observed in Sgr C. A comparison between physical conditions in Sgr C with those of high star formation sources could allow to find the parameters that suppress the birth of stars in this region of the Galactic Center.
Effects of movement artifacts in nuclear hybrid modalities for image diagnostic
Authors: Sánchez Jéssica Núñez , Escudero Pedro , Morán Julio Valverde , Roca Julia Garayoa , Río Margarita Chevalier del
Published: April 2022

In the obtention of medical images, the patients’ movement can modify the identification of the body components in an image. The combination of imaging techniques may not always be a solution to improve the imaging quality; therefore, an artifact analysis is commonly required prior to applying an imaging procedure in patients. In this work, we systematically evaluated the movements’ artifacts caused by the patients’ breathing during the images acquisition and their impact on the fusion of SPECT and CT modalities. We used a specific phantom placed on a platform to emulate the respiratory movement, finding artifacts not appreciable under the standard condition used to obtain the SPECT images due to its low spatial resolution. The artifacts produced a deformation of elements on the images. Therefore, image processing was necessary to identify the registration accuracy with SPECT and CT modalities in two states (phantom at rest and for a phantom with simulated respiratory movements). A systematic difference was obtained for the first case (11.7 mm), and a range of (7.4 mm to 16.1 mm) for the second one. For the volumes’ evaluation, the optimal threshold value for CT was 0.40 and for SPECT was 0.25, giving a rapid solution to reduce the artifacts’ impact on medical images.
Design and construction of a low-cost 3D-printed portable LIBS system
Authors: Ormachea O , Villazon A , Oporto O
Published: April 2022

Laser-Induced Breakdown Spectroscopy (LIBS) is a widely used non-destructive analysis technique, which is however costly. In this paper we present the development of a low-cost 3D-printed portable LIBS system designed and built with a Technology Readiness Level 5 (TRL 5), i.e., technology validated in a relevant environment. The proposed LIBS system is compact and includes a passive Q-switch Nd3+:YAG pulsed laser, a handheld measuring device, a power supply, an optical spectrometer and a processing software. The electronic control system guarantees a stable laser triggering, thanks to the use of optical connections (optocouplers) avoiding wired electrical connections of the circuits. In addition, we found the correct energy characteristics of the passive Q-switch regime, to generate a single laser pulse, thus making the system operate more efficiently. Our low-cost 3D-printed portable LIBS system was validated with several tests with real samples of atomic elements (i.e., lithium, copper, silver, gold and lead).
Surface charge distribution characteristics on insulating materials under negative corona in sphere-plane gaps
Authors: Huang Jingwen , Xiu Liancheng , Yue Guohua , Yi Fan , Qi Jin
Published: April 2022

The accumulation of space charge on the insulation surface can affects the distribution of the total electric field. The surface charge distribution characteristics of dielectrics under negative corona have been studied using spherical plate gaps in this paper. In order to measure the surface potential of three insulating materials under the influence of a DC corona by vibrating electrostatic probe. The experiment tested the surface potential of silicone rubber circular specimen and two umbrella-type disks with different curvatures under negative corona in a spherical gap. Afterwards, a new inversion algorithm was proposed in order to convert the surface potential to a surface charge density. Potential spots were found on the surface of silicone rubber, and the degree of charge clustering of umbrella-type disks was positively correlated with curvature. This experiment will serve as a foundation for future research on the surface charge distribution characteristics of insulation in HVDC corona equipment. Meanwhile, it can also be applied to optimize the insulation design.
Exploration of Exoplanets transiting Red Dwarfs within 50 ly of the Sun
Authors: Zhu Xicheng , Liu Jinkun , Jiang Tianlei , Wang Chaohang
Published: April 2022

Many will say that other stars’ sizes are about the same as the Sun’s. That is not quite true. The Sun is known to be a yellow dwarf. However, the most common stars are red dwarfs, the smallest and coolest stars on the main sequence, a continuous band of stars that appears on plots of stellar color versus brightness. Compared to the sun, they are lower in luminosity, making them harder to detect, as the TESS gathers the flux of the stars, directly proportional to the luminosity, the fixed brightness of a star. However, their small size offers key advantages to searching for Earth-like planets. For instance, the habitable zone is closer to the star, making transits easier to detect due to frequency. This work will explore the red dwarfs that are in Jen Winter5’s catalog that we identify to have transiting planets from and present the calculated parameters of the star systems.
Application Analysis of New Technology of Weather Radar in Disaster Prevention and Mitigation Service of Power Grid
Authors: Fan Weinan , Xu Zhong , Liu Junxiang , Wang Yong , Mo Wenxiong
Published: April 2022

Meteorological radar technology has a very important application in power grid disaster prevention and mitigation. Radar technology is used to measure related disaster information, so that people can better take preventive measures and reduce the impact and loss of disasters on the power grid. Using the detection data of meteorological radar, the types of severe weather are automatically identified and divided, and objective short-term nowcasting and forecasting are automatically carried out. The generated early warning products are organically combined with the geographic information system to realize the accurate forecast of short-term severe weather, and accurately locate the power grid equipment through the spatial analysis service engine.
Non-Hermitian Floquet topological phases in one-dimensional system
Authors: Yang Zhengtan , Li Haoze
Published: April 2022

Periodically driven non-Hermitian systems have attracted a lot of attention due to their intriguing topological phases. In this work, we propose a periodically driven non-Hermitian one-dimensional system, which features rich Floquet topological phases. The non-Hermitian Floquet topological phases are characterized by a pair of topological winding numbers, and the non-Hermitian system demonstrates a bulk-edge correspondence.
Long-term stability of the toroidal current measurement at JET using fibre optics current sensor
Authors: Gusarov A. , Leysen W. , Beaumont P. , Boboc A. , Wuilpart M. , Dandu P. , Croft D. , Bekris N. , Batistoni P.
Published: April 2022

The Fibre Optic Current Sensor (FOCS) is a system that will perform plasma current measurements at ITER during long plasma discharges under intense nuclear radiation. These measurements are important for safe machine operation. The FOCS must perform well in a harsh tokamak environment, which include strong magnetic fields, high temperatures, and also significant levels of neurons and high energy photons. JET is a unique machine where the impact of such conditions on the sensor performance can be investigated experimentally in representative conditions. In this work we analyse stability of the fibre Verdet constant using data obtained with two polarisation detection based FOCS systems installed at JET and operated in various machine scenarios with currents up to 4.2 MA. Analysis of data accumulated during more than four years demonstrates that long-term Verdet constant’s changes are less than 0.5%. However, on a month time scale, windows with deviations up to ±9% from the average value are observed. The reason for these windows is unknown at the moment and will be studied in a future.
Simulations of the nEDM@SNS light collection system efficiency
Authors: Loomis D.A. , Cianciolo V. , Leggett E.
Published: April 2022

A system for collecting the scintillation light produced by the capture of ultra-cold neutrons (UCN) on polarized 3He is discussed and results from simulations of its performance are presented. This system will be implemented in nEDM@SNS, the experiment searching for the neutron electric dipole moment (nEDM) at the Spallation Neutron Source (SNS) at Oak Ridge National Laboratory. Simulation results show that the light collection system detects on average 17 photoelectrons per UCN-3He capture event (sufficient to generate a robust signal), reconstructs the event location in the beam direction to approximately 3 cm accuracy, detects capture events with a high and spatially uniform efficiency (0.95 with 1% variation), and rejects greater than 50% of beta decay background events.
Valley-polarized quantum anomalous Hall insulator in monolayer

RuBr2
Authors: Guo San-Dong , Mu Wen-Qi , Liu Bang-Gui
Published: April 2022

The coexistence of an intrinsic ferrovalley (FV) and nontrivial band topology attracts intensive interest, both for its fundamental physics and for its potential applications, namely a valley-polarized quantum anomalous Hall insulator (VQAHI). Here, based on first-principles calculations by using a generalized gradient approximation plus a U (GGA + U) approach, the VQAHI induced by electronic correlation or strain can occur in monolayer

R
u
B

r
2

. For perpendicular magnetic anisotropy (PMA), the FV to half-valley-metal (HVM) to quantum anomalous Hall (QAH) to HVM to FV transitions can be driven by increasing the electron correlation U. However, there are no special QAH states and valley polarization for in-plane magnetic anisotropy. By calculating the actual magnetic anisotropy energy (MAE), the VQAHI can indeed exist between two HVM states due to PMA, a unit Chern number/a chiral edge state and spontaneous valley polarization. The increasing U can induce VQAHI, which can be explained by a sign-reversible Berry curvature or a band inversion between d

xy
/

d

x
2

−

y
2

and

d

z
2

orbitals. Even though the real U falls outside the range, the VQAHI can be achieved by strain. Taking U = 2.25 eV as a concrete case, the monolayer

R
u
B

r
2

can change from a common ferromagentic (FM) semiconductor to VQAHI under about 0.985 compressive strain. It is noted that the edge states of VQAHI are chiral-spin-valley locking, which can achieve complete spin and valley polarizations for low-dissipation electronic devices. Both the energy band gap and the valley splitting of VQAHI in monolayer

R
u
B

r
2

are higher than the thermal energy of room temperature (25 meV), which is key for device applications at room temperature . It is found that the electronic correlation or strain have important effects on the Curie temperature of monolayer

R
u
B

r
2

. These results can be readily extended to other monolayer

M
X
Y

(M = Ru, Os; X/Y = Cl, Br I). Our work emphasizes the importance of electronic correlation and PMA to study FV materials, and provides a pathway to realize VQAHI.
Preparation and characterization of α-Fe2O3/Fe3O4 heteroplasmon nanoparticles via the hydrolysis-combustion-calcination process of iron nitrate
Authors: Liu Tao , Zhang Shuting , Wang Zhou , Xu Yueyang
Published: April 2022

In this work, a feasible and facile hydrolysis-combustion-calcination process of ferric nitrate for the preparation of magnetic α-Fe2O3/Fe3O4 heteroplasmon nanoparticles was represented. The influences of hydrolysis time, hydrolysis temperature, Fe3+ concentration, anhydrous ethanol volume, calcination time, and calcination temperature on the properties of α-Fe2O3/Fe3O4 heteroplasmon nanoparticles were investigated. According to a series of characterization analysis, the optimal preparation conditions were confirmed: 0.05 M Fe(NO3)3·9H2O was hydrolyzed at 90 °C for 8 h, and then the precursor was calcined at 200 °C for 2 h with 20 ml anhydrous ethanol. While, the morphology of α-Fe2O3/Fe3O4 heteroplasmon were spherical structures with the average particle size of about 46 nm, and their saturation magnetization was 54 emu g−1. The α-Fe2O3/Fe3O4 heteroplasmon nanoparticles possessed controllable magnetic properties and a more stable state, which suggested promising applications.
Impact of Cr content on the thermoelectric properties of the Cr/Sb co-doped Mg2.2−xCrx(Si0.3Sn0.7)0.98Sb0.02 compound
Authors: Ju Jia , Fang Mengfei , Cai Hong , Yin Kang , Yan Chen
Published: April 2022

The n-type Cr/Sb co-doped Mg2.2−xCr
x
(Si0.3Sn0.7)0.98Sb0.02 (0.0025 ≤ x ≤ 0.01) compounds were successfully fabricated by applying the solid state reaction-spark plasma sintering (SPS) technique. The impact of the active Cr content on the thermoelectric properties of the co-doped compound was systematically studied. Insights from the x-ray diffraction (XRD) results indicate the existence of single-phase material of the prepared compounds. Interestingly, the lattice constant and the electrical conductivity of the samples increases with the decrease of the Seebeck coefficient as the Cr content is becomes bigger. All the fabricated compounds could achieve an excellent power factor (PF) of 3.8–4.9 mWm−1K−2 in the range of 300–800 K. The lattice thermal conductivity declines with the increasing Cr amount. More specifically, the lowest κ
L
of about 0.5 W∙m−1∙K−1 was obtained while x = 0.01 at 650 K. The figure of merit (ZT) is also reduced by increasing the Cr content. A high ZT value of 1.4 was obtained while x = 0.0025 at 700 K.
Computing equilibrium measures with power law kernels
Authors: Gutleb Timon , Carrillo José , Olver Sheehan
Published: April 2022

We introduce a method to numerically compute equilibrium measures for problems with attractive-repulsive power law kernels of the form
<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" alttext="upper K left-parenthesis x minus y right-parenthesis equals StartFraction StartAbsoluteValue x minus y EndAbsoluteValue Superscript alpha Baseline Over alpha EndFraction minus StartFraction StartAbsoluteValue x minus y EndAbsoluteValue Superscript beta Baseline Over beta EndFraction">

K
(
x
−
y
)
=

|

x
−
y

|

α

α

−

|

x
−
y

|

β

β

K(x-y) = \frac {|x-y|^\alpha }{\alpha }-\frac {|x-y|^\beta }{\beta }

using recursively generated banded and approximately banded operators acting on expansions in ultraspherical polynomial bases. The proposed method reduces what is naïvely a difficult to approach optimization problem over a measure space to a straightforward optimization problem over one or two variables fixing the support of the equilibrium measure. The structure and rapid convergence properties of the obtained operators result in high computational efficiency in the individual optimization steps. We discuss stability and convergence of the method under a Tikhonov regularization and use an implementation to showcase comparisons with analytically known solutions as well as discrete particle simulations. Finally, we numerically explore open questions with respect to existence and uniqueness of equilibrium measures as well as gap forming behaviour in parameter ranges of interest for power law kernels, where the support of the equilibrium measure splits into two intervals.
The Oxford Encyclopedia of International Criminology
Authors: Erez Edna , Ibarra Peter
Published: April 2022

72 long form essays

Criminology in the 21st century has gone global. It has increasingly been drawn to thinking and research that addresses criminological matters in international, transnational, and comparative registers. Issues at the intersection of criminology/criminal justice and social forces, economic policies, political conflict, national security concerns, legal changes and reforms, environmental issues, legacies of colonialism, technological developments and more are best understood when framed as global phenomena. The Oxford Encyclopedia of International Criminology includes state of the art essays that offer critical reviews of scholarship – including theoretical, empirical, and methodological work – on crime and victimization and the social and legal responses that both receive; historical, social, cultural, legal, and interpretive processes underlying crime and justice; problems of equity and social transformation that increasingly drive debate and discussions of policy, international law, and political activism. The contributors are established and highly distinguished academics as well as emerging scholars whose work is having an impact on their respective fields. They are an international cast of writers drawn from both the Global North and Global South, representing multiple disciplinary orientations, as well as interdisciplinary perspectives. Aside from covering the major issues in their subject areas and incorporating useful bibliographies, the authors offer guidance on how to further explore the various aspects of the topics. The Oxford Research Encyclopedia of International Criminology will prove helpful to students, scholars, and the informed public interested in learning about cutting edge issues in the study of crime and justice in a comparative, global context.
Protestantism
Authors: Pearsall Sarah M. S.
Published: April 2022

‘Protestantism’ argues for the importance of polygamy in at least some branches of radical Protestantism. Marriage took on new significance among Protestants as celibacy was no longer upheld as the ideal, and the sacrament of marriage, regulated by the church, increasingly came to be seen as a civil and secular matter. From sixteenth-century events in the German city of Münster to a range of tracts by authors, including Martin Luther and John Milton, to eighteenth-century British treatises by Methodist minister Martin Madan to American Jacob Cochran and his ideas of “spiritual wifery” in the nineteenth century, there have been a range of Protestant defenses of polygamy over the centuries.
ToxinPred2: an improved method for predicting toxicity of proteins
Authors: Sharma Neelam , Naorem Leimarembi Devi , Jain Shipra , Raghava Gajendra P S
Published: April 2022

Proteins/peptides have shown to be promising therapeutic agents for a variety of diseases. However, toxicity is one of the obstacles in protein/peptide-based therapy. The current study describes a web-based tool, ToxinPred2, developed for predicting the toxicity of proteins. This is an update of ToxinPred developed mainly for predicting toxicity of peptides and small proteins. The method has been trained, tested and evaluated on three datasets curated from the recent release of the SwissProt. To provide unbiased evaluation, we performed internal validation on 80% of the data and external validation on the remaining 20% of data. We have implemented the following techniques for predicting protein toxicity; (i) Basic Local Alignment Search Tool-based similarity, (ii) Motif-EmeRging and with Classes-Identification-based motif search and (iii) Prediction models. Similarity and motif-based techniques achieved a high probability of correct prediction with poor sensitivity/coverage, whereas models based on machine-learning techniques achieved balance sensitivity and specificity with reasonably high accuracy. Finally, we developed a hybrid method that combined all three approaches and achieved a maximum area under receiver operating characteristic curve around 0.99 with Matthews correlation coefficient 0.91 on the validation dataset. In addition, we developed models on alternate and realistic datasets. The best machine learning models have been implemented in the web server named ‘ToxinPred2’, which is available at https://webs.iiitd.edu.in/raghava/toxinpred2/ and a standalone version at https://github.com/raghavagps/toxinpred2. This is a general method developed for predicting the toxicity of proteins regardless of their source of origin.
Electrocardiographic biomarker based on machine learning for detecting overt hyperthyroidism
Authors: Choi Byungjin , Jang Jong Hwan , Son Minkook , Lee Min Sung , Jo Yong Yeon , Jeon Ja Young , Jin Uram , Soh Moonseung , Park Rae Woong , Kwon Joon myoung
Published: April 2022

Aims

Although overt hyperthyroidism adversely affects a patient’s prognosis, thyroid function tests (TFTs) are not routinely conducted. Furthermore, vague symptoms of hyperthyroidism often lead to hyperthyroidism being overlooked. An electrocardiogram (ECG) is a commonly used screening test, and the association between thyroid function and ECG is well known. However, it is difficult for clinicians to detect hyperthyroidism through subtle ECG changes. For early detection of hyperthyroidism, we aimed to develop and validate an electrocardiographic biomarker based on a deep learning model (DLM) for detecting hyperthyroidism.

Methods and results

This multicentre retrospective cohort study included patients who underwent ECG and TFTs within 24 h. For model development and internal validation, we obtained 174 331 ECGs from 113 194 patients. We extracted 48 648 ECGs from 33 478 patients from another hospital for external validation. Using 500 Hz raw ECG, we developed a DLM with 12-lead, 6-lead (limb leads, precordial leads), and single-lead (lead I) ECGs to detect overt hyperthyroidism. We calculated the model’s performance on the internal and external validation sets using the area under the receiver operating characteristic curve (AUC). The AUC of the DLM using a 12-lead ECG was 0.926 (0.913–0.94) for internal validation and 0.883(0.855–0.911) for external validation. The AUC of DLMs using six and a single-lead were in the range of 0.889–0.906 for internal validation and 0.847–0.882 for external validation.

Conclusion

We developed a DLM using ECG for non-invasive screening of overt hyperthyroidism. We expect this model to contribute to the early diagnosis of diseases and improve patient prognosis.