bluuebunny/crossref_metadata_2025_split huggingface dataset:
Prediction models for pulmonary function during acute exacerbation of chronic obstructive pulmonary disease
Authors: Chen Jing , Yang Zhao , Yuan Qun , Xiong Da-xi , Guo Li-quan 
Published: November 2020

Abstract

Objective:
The pulmonary function test is an effort-dependent test; however, during acute exacerbation of chronic obstructive pulmonary disease (AECOPD), patients are unable to effectively cooperate due to poor health. The present study aimed to establish prediction models that only require demographic and inflammatory parameters to predict pulmonary function indexes: forced expiratory volume in one second (FEV1) and forced vital capacity (FVC). Approach: The goal was to establish prediction models based on multi-output support vector regression. A total of 143 subjects received a peripheral blood examination and pulmonary function test. The demographic and inflammatory parameters were used as input features, and FEV1 and FVC were used as the target features in prediction models. Three models (mixed model, severe model and nonsevere model) were established with FEV1 < 1 l as the threshold of severe episodes of AECOPD. The values of FEV1 and FVC from the pulmonary function tests were compared with the prediction models to validate the performances of the developed prediction models. Main results: The severe and nonsevere models’ prediction performances were better than that of the mixed model. The mean squared errors were lower than 0.05 l2, and the decision coefficients (R
2) were higher than 0.40. The two-tailed t-test results showed that for both severe and nonsevere models, the absolute percentage errors of FEV1 and FVC were within 10%. Significance: Our study shows the feasibility of predicting the pulmonary function indexes FEV1 and FVC with demographic and inflammatory parameters when the pulmonary function test fails to be implemented, which is beneficial for the treatment of AECOPD.
Selective tuning of Hilbert spaces in states encoded with spatial modes of light
Authors: Anwar Ali , Lal Nijil , Prabhakar Shashi , Singh R P 
Published: November 2020

Abstract
Spatial modes of light directly give the most easily accessible degree of freedom that span an infinite dimensional Hilbert space. The higher dimensional spatial mode entanglement realized using spontaneous parametric down conversion (SPDC) process is generally restricted to the subspace defined by a single spatial mode in pump. Access to other modal subspaces can be realized by pumping beams carrying several easily tunable transverse modes. As a proof of principle experiment, we generate twin-photon states in an SPDC process with pump as a superposition of first order Laguerre–Gaussian (or Hermite–Gaussian) modes. We show that the generated states can be easily tuned between different subspaces by controlling the respective modal content in the pump superposition.
Power network quality analysis and harmonic control of large electric drive test station
Authors: Dengdong Meng , Wu Wen 
Published: November 2020

Abstract
During the operation of large-scale electric drive test-bed, the driving and loading frequency conversion equipment will produce many different frequency harmonic currents due to their nonlinear characteristics, which will not only affect each other, but also interfere with other transmission and distribution equipment, resulting in current and voltage waveform distortion. In this paper, the operation conditions of a large power drive test bench are analyzed and studied, and the power quality control solution is proposed. The test results prove the effectiveness of the control measures.
Analysis and Verification of Algeria KAE 3MWp Solar Power Plant Electrical Capacity Calculation Report
Authors: Ye Xiang 
Published: November 2020

Abstract
The electrical capacity calculation report of Algeria KAE 3MWp Solar Power Plant is specifically analysized and verified. The analysis results show that the EPC contractual and conceptional design is applicable and further optimization works is possible to be implemented during construction design stage, the technical requirements for both electricity production and PR values are confirmed within efficient ranges.
Parametric Modelling and Seismic Analysis of 220kV Power Distribution Equipment in Electrical Substation
Authors: Liu Wei , Li Sheng , Zhao Mingguan , Lu Zhicheng , Zhang Xiaojun , Fu Guangzhi , Meng Xianzheng 
Published: November 2020

Abstract
Power grid is an important part of the earthquake lifeline project. As electrical substation is the node of the power grid, and the safety evaluation of the substation under earthquakes is essential. There are a wide variety of electrical equipment in substations, and multi pieces of equipment are interconnected to form the complex circuits. Seismic modelling of substation equipment requires engineering researchers to have an accurate understanding of the structure of electrical equipment, as well as to collect complete electrical equipment structural parameters. This process takes a lot of time and effort. This paper proposed a parametric modelling method for substation equipment, which can achieve effectiveness in seismic modelling. Parametric modelling and seismic analysis of high-voltage equipment of a 220 kV substation in Xinjiang is carried out, which verified the validity and applicability of the method.
One-point method for speed strategy optimization based on slope simplification and speed limit prediction
Authors: Han Bing , Xing Jian , Zhong Jikun 
Published: November 2020

Abstract
The automatic driving of trains is an inevitable trend of the modern development of railway transportation, and it is also a necessary requirement for energy conservation and emission reduction. A train automatic driving speed planning scheme with only one operation state transition point in the simplified slope section is proposed based on slope simplification principle and speed limit regulation on an interval line, which reduces the control complexity and energy consumption for automatic driving. An improved fitness function of genetic algorithm (GA) is explored to solve an operation state transition point position of the train, then train energy-saving operation strategy is presented. Practical energy costing experiment for freight train (HXD3) with 2,800 tons for a 33.7km line on Bin-Zhou railway line is obtained and compared with the proposed algorithm. Results show that energy consumption is saved by 15.2% for the speed strategy from the proposed method. So operation strategy is simplified greatly because of only one state transition point in a simplified interval which is more suitable for automatic driving. On the other hand, one point operation strategy is also more energy efficient than manual manipulation. Therefore, the proposed method provides a simple and efficient control strategy for train automatic driving.
Effect of Insulator Bulk Conductivity Non-uniformity on Surface Charge Accumulation
Authors: Zhu Qingdong , Zhu Wenbing , Zhu Mengzhao 
Published: November 2020

Abstract
In order to clarify the effect of insulator bulk conductivity non-uniformity, controlled by electric field, on surface charge accumulation under dc high voltage, a simulation model involving multi-physics, which includes transition from initial capacitive to stationary resistive field, is established. In terms of this, the characters of surface charge accumulation are obtained. It is found that non-uniformity of electric conductivity contributes to the change of surface charge distribution profile, but not to the increase of the maximum surface charge density when the applied voltage is less than 1000 kV. After voltage exceeds 1000 kV, the maximum charge density becomes smaller compared to the case with uniform conductivity. The results indicate that electric conductivity non-uniformity relating to electric field is a source contributing to surface charge accumulation through insulator bulk, and should not be neglected.
Compound Control Scheme Based on Repetitive Controller And Proportional Controller In Building Distribution Grid
Authors: Li Shan-Shou , Wu Yue-Yue , Chao-Zan XU 
Published: November 2020

Abstract
This paper proposes a compound control scheme of three-Phase four-Leg (3P4L) SVG based on the combination of repetitive controller and proportional controller, for the purpose of independently compensating the zero-sequence current under the conditions of load imbalance. To begin with, the overall control scheme of the system is given, in which the repetitive controller and P-controller are connected in parallel. Then, we concluded the recommended scheme is completely equivalent to the series scheme, hence the proportional controller and the repetitive controller can be designed independently. After that, a step-by-step design example of open-loop proportional controller and closed-loop repetitive controller are described. Moreover, the grid voltage feed-forward block is adopted for suppressing the influence of harmonics voltage in grid. Last but not least, Simulation experiments are carried out, and the results demonstrate that the proposed scheme can effectively improve the dynamic performance and stability of 3P4L-SVG under the conditions of load imbalance or grid voltage imbalance.
Balance control of quadruped robot based on model predictive control
Authors: Wu ChengYe , Wei Qing , Zhang Cong , An HongLei 
Published: November 2020

Abstract
Aiming at the steady motion of the quadruped robot during support period of the locomotion, it is necessary to plan the ground reaction force (GRF) of legs. For the control of the plane height of the robot body, we take the standing balance of the simply modelled quadruped robot as the research object, and use the model predictive control algorithm to plan quadruped robot’s GRF of its position and attitude control, and then map the force to the operating space through the Jacobian matrix of the joint space to obtain the torque of the joint space. This paper uses MATLAB and RecurDyn for the co-simulation, and obtains good control results from it. At the end, we analyze the feasibility and rationality of its algorithm application by comparing it with the traditional balance controller. The work above provides the basis for the control and design of the subsequent quadruped robot motion planning.
A new parameter adaptive control of four-dimensional hyperchaotic system
Authors: Liao Xiaokang , Chen Zili , Lin Jianhui 
Published: November 2020

AbstractBy adding a state feedback controller to a three-dimensional chaotic system, a new four-dimensional hyperchaotic autonomous system is constructed. The nonlinear dynamic behavior of the system is deeply investigated, including power spectrum, Poincare cross section, Lyapunov exponential spectrum and bifurcation graph. The analysis shows that the new four-dimensional hyperchaotic system has complex chaotic motions with different parameters, and the related analog chaotic circuits are designed. Finally, a parameter adaptive controller is designed to achieve global stability control of chaotic systems. The effectiveness of the proposed method is verified by numerical simulation.
Application and Analysis of Big Data Technology in Smart Grid
Authors: Wang Shuchun , Sun Xiaoguang , Geng Jianyu , Han Yuan , Zhang Chunyong , Zhang Weihua 
Published: November 2020

Abstract
In order to make the modern power system more intelligent, various data acquisition equipment and information management systems are required, such as smart meters, remote terminal units (RTU), phasor measurement units(PMU), power distribution management systems(DMS), and energy management systems(EMS), customer management system(CMS), power generation management system(GMS) have been widely installed. These systems create large amounts of data, which is the main source of smart grid big data. Researching advanced data analysis technology is the most urgent task for the development of smart grid. It can make the best decision for the control and operation of the grid, and can improve the flexibility, safety, reliability and efficiency of the power system. This article analyses the cause of smart grid big data and the importance of data analysis, and discusses the development trend of big data technology. Selectively analysed the source and type of smart grid big data, summarized the characteristics of smart grid big data, gave various application scenarios, and introduced the smart grid big data analysis platform and the functions being developed.
Research on Voltage Control of Multi Terminal Flexible Medium Voltage DC Distribution Network
Authors: Yang Xiaoping , Xiao Feng 
Published: November 2020

Abstract
In order to solve the problem that the original control strategy cannot meet the voltage quality requirements of the system under various operation modes due to the expansion of DC distribution network scale, this paper studies the voltage control strategy of a ring type medium voltage DC distribution network. Firstly, the traditional control method is improved, the droop control is added to the margin control as the slave station control method. At the same time, the DC transformer connected with the energy storage is used as the backup voltage regulating station in case of power shortage to meet the voltage quality requirements of the system in normal operation and fault. Then, a DC voltage control strategy based on depth first search is proposed to solve the problem of voltage deviation caused by system fault, so that the distribution network can automatically adjust the control according to the real-time structure in case of fault and improve the voltage quality. Finally, the proposed control strategy is simulated in PSCAD / EMTDC to verify the effectiveness of the control strategy.
Optimal capacity allocation of thermal storage system considering peak regulation ancillary services
Authors: Zhang Tao , Zhao Guanxiong , Wang Shuwen , Wang Shunjiang , Li Yang 
Published: November 2020

Abstract
Limited by the operation mode of ‘heat-set’ is one of the main reasons for the large amount of wind abandonment in Northeast China. Reasonable allocation of electric heat storage system is an effective means to improve the wind power absorption capacity of regional power grid. In this paper, an optimal capacity allocation model of electric heat storage system considering peak regulation auxiliary services is proposed, and the optimal capacity of electric heat storage system is solved based on game theory. Firstly, the economic benefits of each stakeholder participating in peak regulation ancillary service market are analyzed by allocating electric heat storage equipment in thermal power plants. Secondly, a bi-level programming model for optimal capacity allocation of electric thermal storage system is established. Finally, the model is optimized by particle swarm optimization and Cplex hybrid optimization method. The optimal configuration scheme of the electric heat storage system is obtained by solving the optimization problem. The example shows that the model is reasonable and effective.
Clearing approach for day-ahead electricity spot market based on fast calibration of conditional section constraints
Authors: Wu Yang , Li Xiufeng , Jiang Yan , Gao Daochun , Duan Ruiqin , Zhao Zhenyu , Yin Ziheng , Sun Yujun 
Published: November 2020

Abstract
With the expansion of the pilot area of the electricity spot market in China, how to consider the conditional section to clear the spot market is a new problem faced by dispatching operators. This paper first analyses the impact of conditional section constraints on the clearing of the spot market. Secondly, in order to improve the efficiency of spot market clearing calculation, based on the mode of posterior addition, a fast method of checking condition section is proposed. Thirdly, this method is incorporated into the framework of day-ahead spot market clearing. Finally, the validity of the method is verified by an example analysis of the IEEE118-node system.
Optimal Planning Method of Distribution Transformer Network for Seasonal Load
Authors: Wang Zhanwei , Chen Haidong , Deng Shiyu , Wu Jian , Li Demin , Li Jiwei , Xie Yan 
Published: November 2020

Abstract
Taking into account the reliability of power supply, this paper proposes an optimal planning method for distribution transformer network adapting to seasonal load in order to improve the low efficiency of equipment utilization in rural coal-to-electricity conversion areas. In this method, a bi-level programming model of distribution transformer network is constructed to minimize the overall cost. Voronoi is used to plan the distribution transformer at the upper level, Prim algorithm is used to plan the low-voltage power supply line at the lower level, and genetic algorithm is used to optimize the solution (seek the optimal solution). Finally, the feasibility of this method is verified by the planning of distribution transformer in typical power supply areas. The analysis of examples shows that the distribution transformer loss can be reduced by establishing the low-voltage tie-line between distribution transformers and the transformation of operation mode, which also provides the basis for the load transfer under the low-voltage line fault.
Construction of a value-based equipment development decision analysis index system
Authors: Wang Na , Li Kaiyan , Xue Fengtong , Gong Maohua 
Published: November 2020

Abstract
This article summarizes the feasibility and related achievements of the value-focused thinking in the field of equipment development. On this basis, in response to previous equipment development decisions that mainly considered combat effectiveness, this paper analyzes equipment development decision-making issues from the two dimensions of mission and resource constraints from the perspective of value, constructs a decision value model, and sets a scoring function for it, Using the final value score as the basis for the selection of equipment plans, aiming to provide a method reference for the decision-making of China’s equipment construction plans.
Subsynchronous oscillation mitigation strategy based on adaptive band-stop filter in DFIG-based wind farms
Authors: Yang Hongyu , Xu Shanshan , Wu Xi , Gu Wen , Mei Rui , Lyu Wan 
Published: November 2020

Abstract
Subsynchronous Oscillation (SSO) may exist in doubly-fed induction generator (DFIG)-based wind farms connected with a series compensated transmission network, also called subsynchronous control interaction (SSCI). Different from thermal power units, the SSO frequency of wind farm varies with the change of system operating conditions, and has the characteristic of time-varying. When the operating conditions change, the existing mitigation strategies may lose the effect. To address this issue, a SSO mitigation strategy based on adaptive band-stop filter (ABSF) is proposed in this paper: When SSO occurs in the system, the ABSF parameter is adjusted according to the oscillation frequency measured by PASTd algorithm to filter out the subsynchronous component in the RSC loop effectively, so as to break the generation path of SSO and suppress SSO. Compared with the existing mitigation strategies, the proposed strategy doesn’t need the mathematical model of the system, and can ensure strong robustness under various operating conditions. Finally, the effectiveness and robustness of the proposed strategy are verified on the Matlab/Simulink.
Analysis of Factors Affecting Temperature Rise of Oil-immersed Power Transformer
Authors: Sun Cheng-chao , Xiao Chi , Hou Jun , Kong Liang , Ye Jian , Yu Wen-jian 
Published: November 2020

Abstract
The key factors that affect the operation state of power transformer include thermal problem and insulation problem. It is of great significance to pay attention to the factors affecting the temperature rise characteristics of transformer to ensure its stable operation. The temperature rise characteristic model of transformer is established to explore the possibility of replacing mineral oil with plant insulation oil FR3 in this paper. On the basis of calculating the influence of ambient temperature change of external heat source on transformer temperature rise, the relative life loss rate of transformer under different ambient temperature is calculated. The results show that FR3 vegetable oil can replace mineral oil in terms of temperature rise. The temperature of the transformer core and winding hot spot increases with the ambient temperature. When the ambient temperature exceeds 293K, the relative life loss rate of the transformer increases very quickly. Therefore, the transformer should not be kept in an environment where the temperature exceeds 293K for a long time.
Effect of pretreatment on the microstructure of multiwalled carbon nanotubes
Authors: He X L , Tang P J , Wang X Y , Li P Y 
Published: November 2020

Abstract
Four kinds of multi-walled carbon nanotubes pretreated by different methods were studied. Chemically functionalized (hydroxylation and carboxylation) CNTs were prepared by oxidizing original CNTs in H2SO4 solutions of different temperatures and concentrations by KMnO4. Graphitized CNTs were prepared by heat-treating original CNTs in an inert gas at 2800°C for 20 hours. CNTs Nickel plating on the surface was obtained by electroless plating. The effect of pretreatment on the surface state and microstructure of carbon nanotubes was also studied. The results showed that Chemical functionalization could form some functional groups on the surface of CNTs, which could not only improve the compatibility of CNTs with some solvents, but also purified CNTs, which had a positive effect on the preparation of composite materials. High-temperature graphitization treatment could significantly increase the degree of crystallization of carbon nanotubes and reduce structural defects. After electroless nickel plating, evenly distributed nano-sized metal particles were formed on the surface of the CNTs, and the interface between the two was well bonded.
Environmental technology for processing waste from mining and processing plants
Authors: Bobkov Vladimir , Meshalkin Valery , Aristov Vitaly , Dli Maxim 
Published: November 2020

Abstract
This research proposes a system approach for the analysis of volumes, physicochemical, granulometric, lithologic and thermal characteristics of waste from ore-dressing and processing enterprises stored in the dumps (tailing dumps) of ore-dressing and processing plants to assess the economic potential of its use in the system of complex power and resource efficient environmentally safe processing including palletizing machines, conveyor indurating machines and ore–thermal furnaces. The obtained results allow the authors to formulate the basic engineering, technological, economic and environmental requirements for complex chemical and power engineering systems of processing technogenic waste from ore-dressing and processing plants, these results make it also possible to define the degree of variability for the characteristics of the waste lots from various dumps. The paper describes the developed intensional and mathematical formulations for the multiscale problem of optimizing chemical and power engineering processes of technogenic raw materials processing in a complex chemical and power engineering system as a problem for discrete dynamic programming. The distinctive feature of this problem is to take into account the spatio-temporal multistage processing in a moving multilayer mass of pelletized raw material, the intensity of the process of internal moisture transfer and the variables for the control flow of the heat carrier gas.