bluuebunny/crossref_metadata_2025_split huggingface dataset:
Particle-in-cell simulations of asymmetric reconnection driven by laser-powered capacitor coils
Authors: Huang Kai , Lu Quanming , Chien Abraham , Gao Lan , Ji Hantao , Wang Xueyi , Wang Shui 
Published: October 2020

Abstract
During magnetic reconnection, such as in the magnetopause of magnetized planets, the upstream plasma conditions between the two inflow regions are usually different. In this paper, we demonstrate that such a kind of asymmetric reconnection can be studied in the laboratory using the recently proposed experimental scheme where reconnection is driven by laser-powered capacitor coils. Two-dimensional particle-in-cell simulations on the

z
,
r

plane in a cylindrical coordinate are conducted to study magnetic reconnection with the inflow along the

r

direction. Magnetic reconnection is found to be asymmetric with a stronger magnetic field in the inner (small

r

) inflow region and a weaker magnetic field in the outer (large

r

) inflow region due to the cylindrical symmetric geometry. Electron crescent velocity distributions are observed near the flow stagnation point while ion crescent velocity distributions are observed in the region with Larmor electric field. The out-of-plane Hall magnetic field is asymmetric between the two inflow regions with a larger spatial scale in the outer inflow region. This asymmetric Hall magnetic field configuration is different from that in previous studies. The typical reconnection rate increases with a stronger driver and the highest rate is around 0.2

V
A

B
0

, where

B
0

is the typical value of the magnetic field and

V
A

is the Alfven speed. This study provides a new method to experimentally study asymmetric reconnection in the laboratory and has potential applications regarding magnetic reconnection in the magnetopause of magnetized planets.
Vertical 3D gallium nitride field-effect transistors based on fin structures with inverted p-doped channel
Authors: Strempel Klaas , Römer Friedhard , Yu Feng , Meneghini Matteo , Bakin Andrey , Wehmann Hergo-Heinrich , Witzigmann Bernd , Waag Andreas 
Published: October 2020

Abstract
This paper demonstrates the first vertical field-effect transistor based on gallium nitride (GaN) fin structures with an inverted p-doped channel layer. A top-down hybrid etching approach combining inductively coupled plasma reactive ion etching and KOH-based wet etching was applied to fabricate regular fields of GaN fins with smooth a-plane sidewalls. The obtained morphologies are explained using a cavity step-flow model. A 3D processing scheme has been developed and evaluated via focussed ion beam cross-sections. The top-down approach allows the introduction of arbitrary doping profiles along the channel without regrowth, enabling the modulation of the channel properties and thus increasing the flexibility of the device concept. Here, a vertical npn-doping profile was used to achieve normally-off operation with an increased threshold voltage as high as 2.65 V. The p-doped region and the 3D gate wrapped around the sidewalls create a very narrow vertical electron channel close to the interface between dielectric and semiconductor, resulting in good electrostatic gate control, low leakage currents through the inner fin core and high sensitivity to the interface between GaN and gate oxide. Hydrodynamic transport simulations were carried out and show good agreement with the performed current–voltage and capacitance–voltage measurements. The simulation indicates a reduced channel mobility which we attribute to interface scattering being particularly relevant in narrow channels. We also demonstrate the existence of oxide and interface traps with an estimated sheet density of 3.2 × 1012 cm−2 related to the Al2O3 gate dielectric causing an increased subthreshold swing. Thus, improving the interface quality is essential to reach the full potential of the presented vertical 3D transistor concept.
Mesoscopic quantum superposition states of weakly-coupled matter-wave solitons
Authors: Tsarev Dmitriy , Alodjants Alexander , Ngo The Vinh , Lee Ray-Kuang 
Published: October 2020

Abstract
The Josephson junctions (JJs) are at the heart of modern quantum technologies and metrology. In this work we establish quantum features of an atomic soliton Josephson junction (SJJ) device, which consists of two weakly-coupled condensates with negative scattering length. The condensates are trapped in a double-well potential and elongated in one dimension. Starting with classical field theory we map for the first time a two-soliton problem onto the effective two-mode Hamiltonian and perform a second quantization procedure. Compared to the conventional bosonic Josephson junction condensate system, we show that the SJJ-model in quantum domain exhibits unusual features due to its effective nonlinear strength proportional to the square of total particle number, N
2. A novel self-tuning effect for the effective tunneling parameter is also demonstrated in the SJJ-model, which depends on the particle number and rapidly vanishes as the JJ population imbalance increases. The formation of entangled Fock state superposition is predicted for the quantum SJJ-model, revealing dominant N00N-state components at the ‘edges’ for n = 0, N particle number. We have shown that the obtained quantum state is more resistant to few particle losses from the condensates if tiny components of entangled Fock states are present in the vicinity of the major N00N-state component. This peculiarity of the quantum SJJ-model establishes an important difference from its semiclassical analogue obtained in the framework of Hartree approach. Our results are confirmed by studying the first and N-order Hillery–Zubairy criteria applied for studying multiparticle entanglement and planar spin squeezing. The Einstein–Podolsky–Rosen quantum steering represents an important prerequisite for the crossover to the mesoscopic superposition Schrödinger-cat and/or N00N-states. The feasibility in observation for these predicted states of the SJJ-model in the experiments is also discussed by taking into account one- and three-body losses for lithium condensates.
Gibbs mixing of partially distinguishable photons with a polarising beamsplitter membrane
Authors: Holmes Zoë , Mintert Florian , Anders Janet 
Published: October 2020

Abstract
For a thought experiment concerning the mixing of two classical gases, Gibbs concluded that the work that can be extracted from mixing is determined by whether or not the gases can be distinguished by a semi-permeable membrane; that is, the mixing work is a discontinuous function of how similar the gases are. Here we describe an optomechanical setup that generalises Gibbs’ thought experiment to partially distinguishable quantum gases. Specifically, we model the interaction between a polarisation dependent beamsplitter, that plays the role of a semi-permeable membrane, and two photon gases of non-orthogonal polarisation. We find that the work arising from the mixing of the gases is related to the potential energy associated with the displacement of the microscopic membrane, and we derive a general quantum mixing work expression, valid for any two photon gases with the same number distribution. The quantum mixing work is found to change continuously with the distinguishability of the two polarised gases. In addition, fluctuations of the work on the microscopic membrane become important, which we calculate for Fock and thermal states of the photon gases. Our findings generalise Gibbs’ mixing to the quantum regime and open the door for new quantum thermodynamic (thought) experiments with quantum gases with non-orthogonal polarisations and microscopic pistons that can distinguish orthogonal polarisations.
Absorption imaging of trapped atoms in presence of AC-Stark shift
Authors: Bhardwaj Kavish , Ram S P , Singh S , Tiwari V B , Mishra S R 
Published: October 2020

Abstract
In this work, the effect of AC-Stark shift of atomic energy levels in an optical dipole trap (ODT) on in situ absorption imaging of the trapped atoms has been investigated. The Stark shift of various energy levels of 87Rb atoms relevant for trapping in the optical dipole trap (ODT) has been calculated. The spatially varying AC-Stark shift of energy levels due to ODT beam results in position dependent absorption cross-section of the atom at the absorption probe laser wavelength, which significantly modifies the measured optical density (OD) of the trapped atom cloud during the in situ absorption imaging. We have estimated the number of atoms trapped in the ODT taking AC-Stark shift into account. The estimated numbers are found to be higher at higher ODT beam power, making a qualitative agreement with larger trap depth at higher ODT beam power. This work can be particularly useful in estimating the in situ loss rate of atoms from the trap during the evaporative cooling of the trapped atom cloud.
Research on the Development of the Ubiquitous Power Internet of Things
Authors: Lidan Zhou , Zujia Cao , Gang Yao , Dong Liu 
Published: October 2020

Abstract
The dawn of the new century has witnessed the tremendous advancement of society. In response to the requirement of the progress of technologies and enterprise development, the Ubiquitous power Internet of things (UPIOT) is boosting to develop and playing a significant role in China’s power grid which not only connects all aspects of the power system, but also promotes the application and innovation of various new techniques. As time goes by, UPIOT has been the key part to realize the transformation of energy production and consumption which will achieve green and healthy progress of power grid. This paper analyses in detail the concept, main characteristics, construction goals and existing problems of the UPIOT. Besides, the key technologies that contain the big data, cloud computing, the internet of things, 5G, blockchain, artificial intelligence and other technologies are also proposed. Furthermore, this paper introduces different application scenarios of UPIOT and offers some suggestions to accelerate the development of UPIOT.
An Edge Computing Method for Partial Discharge under the Power Internet of Things
Authors: Wang Shaojing , Ren Maoxin , Cao Pei , Xu Peng 
Published: October 2020

Abstract
The recognition of impulse interference for the partial discharge data on the edge computing platform can effectively reduce the false alarm rate in the risk assessment of gas insulated switchgear (GIS). Therefore, an edge computing method for partial discharge is proposed in the paper, which uses the similarity computing among the aggregation of data for each sensor after clustering to match homologous signals. Finally, the algorithm will jointly locate the interference signal and recognize the impulse interference signal by comparing the received signal strength indicator (RSSI) of multiple UHF sensors in/out of GIS equipment. The training set, being consisted of partial discharge and interference signal from the test, is used to contrast the algorithms on the edge computing platform, the result of which indicates that the accuracy rate of the recognition of the impulse interference with the proposed algorithm is 81.4% on the computing platform, with the average processing time for each sample of 7.15s.
Research on System Architecture of Internet Data Center Construction in Substation based on Ubiquitous Function
Authors: Chen Zhang , Yan Zhangy , Jinhua Huang 
Published: October 2020

Abstract
Substation has the advantages of having spare area, close to users, rich communication resources, reliable power supply. By releasing substation site resources, data centers and cloud services can be provided to the society. Construction of Internet Data Center (IDC) with the idle substation resources to realize multi-station integration will economize on social costs and accelerate the development of the digital infrastructure. In this paper, we analysed the participants involved in the expansion data center of the substation. Explore relations among Grid Company, Telecom Operator and User. According to the time sequence of the development of multi-station fusion business, the business time sequence diagram of the substation extended data center station covering the whole business process was designed. Considering the business flow, information flow, and energy flow flows between each section, the dynamic sequence diagram was built. We build the system architecture of business implementation including construction, operation, settlement and other links.
Electricity Prediction under Edge Devices Based on Sparse Anomaly Perception
Authors: Yang Jun , Xu Aidong , Zeng Yonggang , Li Li Cheng , Jiang Yixin , Zhang Yunan , Wen Hong 
Published: October 2020

Abstract
Energy issues are closely related to human development. With the changes of the times and the rapid development of technology, power energy has become one of the indispensable energy in human social life, and is the most important part of energy field in modern society. Electricity prediction, as the basis for power system operation, optimization, and control, is facing new challenges in today’s rapidly evolving energy system environment. A large number of machine learning technology and deep learning technology have been applied to electricity prediction and achieved good results. In the edge computing environment, anomalous data collection is characterized by sparsity and time window, and machine learning regression algorithms are often affected by anomalous data. Electricity prediction under edge devices based on sparse anomaly perception is proposed, which combines the drop out idea and subsample idea to alleviate the above problems to some extent. And it can achieve faster training and more accurate prediction.
Study on Identification of Defect Types in XLPE Cable with Weibull Distribution
Authors: Duan Y B , Ma G Q , Zhang H , Hu X L , Li P F , Fu Y L , Chen Z L , Zhou Y W 
Published: October 2020

Abstract
In order to monitor the insulation condition of XLPE cables which have been one of the most popular equipment used in power transition, a method is proposed in this paper to identify the insulation defects accurately by analysing the Weibull distribution of partial discharge (PD) signals. Experiments were applied on a 10kV 30m XLPE cable and three typical types of insulation defect models were designed and tested. The discharge pulse signals of each defect model were collected and their Weibull parameters were analysed and estimated with the ordinary least square estimation method. Several common pattern recognition methods such as support vector machine (SVM), artificial neural network (ANN) as well as classification and regression tree (CART) were used to test the accuracy of the extracted Weibull parameters. The results verified that it is effective to use the parameters of Weibull distribution for defect identification of XLPE cables and the features are suitable for common pattern recognition models.
Solar Road Power Generation Assessment Based on Coupled Transportation and Power Distribution Systems
Authors: Wu Lingjie , Yuan Yue , Wu Han 
Published: October 2020

Abstract
The rising of energy demand together with environmental protection awareness have attracted worldwide interest in renewable energy, especially photovoltaic (PV). Meanwhile, with the expansion of transportation infrastructure, solar energy has been employed in roadway construction, called solar road. The technology of Solar road offers an opportunity to capture the vast and dispersed solar energy while maximizing the use of land. A PV power generation assessment method for solar road considering coupled distribution and transportation system is proposed in this paper. The dynamic shading caused by traffic flow on solar road is considered as an effect factor which will influence the PV output in the model. The proposed method is examined on a test system with a transportation and a radial distribution network. The numerical results substantiate that the proposed method is an effective tool for assessing the PV power generation of solar road.
Benefit Models and Optimization Clearing Model for Participants in Cloud Energy Storage
Authors: Wu Yanzheng , Zhu Junpeng , Yuan Yue 
Published: October 2020

Abstract
Energy storage can smooth the fluctuation of renewable energy sources and has the characteristic of flexibility, which makes it an important dispatching resource in distribution network. In order to promote the consumption of renewable energy sources and the reasonable configuration of energy storage resources, this paper expands the basic concept of cloud energy storage and puts forward an operation mechanism involving customers, distributed generation operators and the cloud energy storage operator. According to the commercial mode described, we analyze the benefits of the three parties, establish the opportunity cost model on the consumer side and the benefit models of the three parties. Then we propose the energy storage scheduling strategies, use an optimal scheduling model to solve the pricing and clearing problems of cloud energy storage and solve it with the multi-object searching algorithm based on particle swarm optimization algorithm. At last, the case study shows that the method proposed can effectively improve the overall benefits of cloud energy storage participants on the basis of satisfying the load demand of the customers and ensuring the profitability of distributed generation operators.
Meteorological droughts are projected to worsen in Central America’s dry corridor throughout the 21st century
Authors: Depsky Nicholas , Pons Diego 
Published: October 2020

Abstract
Understanding past and projected drought patterns across Central America’s ‘Dry Corridor’ (CADC) is crucial for adaptation planning and impact mitigation, especially in small-scale agricultural communities. We analyzed historical and predicted drought patterns in the CADC by calculating Standardized Precipitation Index (SPI) values from local rain gauge records, reanalysis data and a 20-member ensemble of bias-corrected, downscaled CMIP-5 GCMs at both seasonal (3 month) and annual (12 month) scales. Trends in drought frequency, duration, intensity were assessed for three, 30 year future periods compared to historical values. Our results suggest a decrease in mean annual rainfall of 8%–14% in the CADC under moderate to high emissions scenarios, respectively, by end-of-century (2071–2100) relative to a historical baseline (1950–2005). However, projected changes to drought characteristics under these scenarios are more pronounced, with seasonal-scale droughts projected to lengthen by 12%–30%, intensify by 17%–42% and increase in frequency by 21%–24% by end-of-century. Annual-scale, longer-term droughts are projected to lengthen by 68% under moderate emissions, potentially triple in length under high emissions and to intensify by 27%–74%. These results were similar yet slightly more pronounced for some drought metrics when just considering rainy/cropping season months (May–Oct). End-of-century changes to rainfall reliability and drought occurrence such as these would severely impact millions of vulnerable inhabitants in the CADC and should be considered in adaptation policymaking efforts.
City-size bias in knowledge on the effects of urban nature on people and biodiversity
Authors: Kendal Dave , Egerer Monika , Byrne Jason A , Jones Penelope J , Marsh Pauline , Threlfall Caragh G , Allegretto Gabriella , Kaplan Haylee , Nguyen Hanh K D , Pearson Sue , Wright Abigail , Flies Emily J 
Published: October 2020

Abstract
The evidence base for the benefits of urban nature for people and biodiversity is strong. However, cities are diverse and the social and environmental contexts of cities are likely to influence the observed effects of urban nature, and the application of evidence to differing contexts. To explore biases in the evidence base for the effects of urban nature, we text-matched city names in the abstracts and affiliations of 14 786 journal articles, from separate searches for articles on urban biodiversity, the health and wellbeing impacts of urban nature, and on urban ecosystem services. City names were found in 51% of article abstracts and 92% of affiliations. Most large cities were studied many times over, while only a small proportion of small cities were studied once or twice. Almost half the cities studied also had an author with an affiliation from that city. Most studies were from large developed cities, with relatively few studies from Africa and South America in particular. These biases mean the evidence base for the effects of urban nature on people and on biodiversity does not adequately represent the lived experience of the 41% of the world’s urban population who live in small cities, nor the residents of the many rapidly urbanising areas of the developing world. Care should be taken when extrapolating research findings from large global cities to smaller cities and cities in the developing world. Future research should encourage research design focussed on answering research questions rather than city selection by convenience, disentangle the role of city size from measures of urban intensity (such as population density or impervious surface cover), avoid gross urban-rural dualisms, and better contextualise existing research across social and environmental contexts.
Experimental Investigation of Fluid Flow Hydrodynamics in Porous Medium Pipeline
Authors: Liu Hongsheng , Wu Dan , Liu Lin 
Published: October 2020

Abstract
Porous medium square pipelines with pellet packed bed and cylindrical packed bed are employed to experimentally study the flow characteristics of water. Differences of flow characteristics between the pellet packed bed and cylindrical packed bed, as well as the circular pipe and the square pipe, are discussed by measuring the pipeline pressure drop under different flow rate, and the relationship between the pipe resistance coefficient and flow is analyzed. The results show that the pressure drop per unit length in the square pipe increases with the increase of flow rate and increases with the decrease of pellet diameter. The structure of large diameter pellet packed bed is more advantageous to form a relatively stable flow.
Spectral Filtering of Photovoltaic Cells Using Novel Bio-filter: Silver Coated Hibiscus Extract Using Ethanol Solution
Authors: Emetere M.E. , Adeyemo M. 
Published: October 2020

Abstract
The challenge of solar infrared radiation damage on the photovoltaic (PV) still subsists. This challenge has led to the low patronage of PV in the African solar market despite the purchasing price reduction. This research seeks to proffer solution to this challenge by shielding the surface of the PV panel from solar IR radiation. This solution is expected to also prolong the life span of the PV module. The bio-filter was synthesized using silver nitrate and hibiscus extract. The bio-filter was observed to have increased the current and power output in the polycrystalline panel by 1%. Also, it was observed that the bio-filter reduced the output in the monocrystalline by 2%. This result is adjudged promising as further research on other plant extracts are investigated.
Investigation of Biodegradable Optical filter in a Turbulent Solar Irradiation
Authors: Emetere M.E. , Rokosu A.K. 
Published: October 2020

Abstract
The damage of the solar cells in the photovoltaic (PV) module under harsh weather conditions is particularly an issue in tropical belt of Africa. The focus of this research is to investigate the role of the bio-filter on the PV module under harsh weather. It was discovered that the bio-filter narrows the voltage difference between the maximum and minimum voltages. This unique property of the bio-filter reduces the undulating excitations and de-excitations of electron in the PV module, thereby ensuring that the solar cells do not get damage. It is recommended that this experiment can be optimized via plant extraction techniques, doping techniques and doping concentration.