bluuebunny/crossref_metadata_2025_split huggingface dataset:
Design and implementation of online uninterruptible power supply system based on STM32
Authors: Zhaowei Liu , Jiapeng Luo , Guorong Zhu 
Published: February 2021

Abstract
The application of microprocessors in automation and industry has become more and more extensive, especially the application of embedded microcontroller technology has promoted the development of UPS design. This paper designs an embedded uninterruptible power supply system with adjustable output based on STM32, and uses PID algorithm to optimize the control strategy. The advantage of this system is that the output is adjustable and has high precision, the circuit structure is simple, the output power efficiency is high, the system is small in size, and the cost is low, while the stability and safety of the system are guaranteed.
Analysis and Quantitative Study of China’s Oil and Gas Uncertainties during the “14th Five-Year Plan”
Authors: Zu-xin LI , Jian-ye LIU , Dong-kun LUO 
Published: February 2021

Abstract
As a mining industry which is vital to the national economy, the oil and gas industry is faced with various uncertainties from the exploration and development at the upstream, refining and production at the midstream to the transportation and sale at the downstream. With the implementation of the “Go Global” strategy of the oil and gas industry and the steady progress of the Belt and Road Initiative, a more comprehensive and accurate identification, classification and quantification of the uncertain factors facing the oil and gas industry is required by the “14th Five-Year Plan”. This paper first identifies and classifies the uncertain factors of the oil and gas industry and then analyzes the difference between those uncertain factors from the domestic and overseas perspectives. Different methods of quantifying the uncertainties are also designed from the three dimensions of resource, technology and economy. Based on the development trend of various factors during the “14th Five-Year Plan” period, this paper predicts the quantitative results of uncertainties in the following 10 years.
A novel Fault Diagnosis Method for Power Transmission Lines Based on Improved Deep Belief Network
Authors: Sun Caitang , Xiao Wei , Li Gang 
Published: February 2021

Abstract
With the rapid development of artificial intelligence technology, the application of deep neural networks to power transmission line fault classification is gaining more and more attention from researchers. In this paper, a novel power transmission line fault classification method based on an improved Deep Belief Network is proposed. The Adam algorithm is used to adjust the learning rate. The convergence rate can be faster and the probability of falling into a local extremum is reduced. This paper uses IEEE 30-bus system as an example for simulation experiment. The electrical parameters and their zero components at the key buses of the power system are selected as eigenvalues. Experimental results show that, contrary to conventional Deep Belief Network method, the improved method has higher classification accuracy and faster convergence. When we increase the noise level of the dataset, the improved Deep Belief Network still has better classification effect.
Experimental Research on the Pipe Grouting Quality Based on Antenna Array Radar
Authors: Jun Xie , Xiaoni Gao , Ning An , Xiaohua Zheng 
Published: February 2021

Abstract
Experimental research on the pipe grouting quality is carried out by detecting the concrete test piece with high-frequency antenna array radar. First, the principle of detecting the pipe grouting quality with ground-penetrating radar is introduced, and then the pipe grouting situation is researched systematically and completely with three methods, including the oscillogram of a single wave, grey-scale image (2D imaging) and slice image (3D imaging) of antenna array radar, and the research results are verified with an indoor test model. The results show that: Pipe can be positioned precisely with antenna array ground-penetrating radar; for failure of judgment of the grouting fullness of metal pipes and the grouting fullness situation of non-metal pipes, the pipe grouting quality can be identified with the oscillogram of a single wave, grey-scale image (2D) and slice image (3D) respectively; Radar detection 3D image can present the position of a pipe in the structure intuitively and accurately, and, the pipe material and the pipe grouting fullness can be judged by comparing the radar detection 3D image and the 3D slice image.
Pushover analysis in different lateral force distribution patterns of bridge piers
Authors: Yang Yaobang , Jiao Daokuan , Song Huaidong 
Published: February 2021

Abstract
Basic principles of pushover analysis method and several different lateral force distribution patterns are briefly described in this paper. A long span concrete continuous rigid frame bridge is taken as an example to carry out the pushover analysis under rarely occurred earthquake. The demand curve and the capability curve are combined to form the capability spectrum to evaluate the seismic performance of the bridge. Analysis results show that different lateral force distribution patterns have great influence on Pushover analysis results.
New infrastructure-oriented power network security supervision innovative mechanism and system architecture
Authors: Liu Chao , Yang Jiaxuan , Qiang Ren , Yuan Linlin , Ju Wei , Xia Yongxin , Mahato Nawaraj Kumar 
Published: February 2021

Abstract
Under the framework of latest digital infrastructure, the application of emerging technologies in the power system has become more in-depth, and the security of power networks has ushered the new challenges. Facing new challenges, power network security inspectors need to keep pace with the times and make innovations in response to the new circumstances. This paper summarizes and analyses the existing network security supervision specifications and practical experience of the State Grid Corporation of China, and combines the laws, regulations, standards and corporate document requirements such as the Cyber Security Law and the Classified Protection 2.0 National Standard, based on the new network security characteristics of the new power digital infrastructure, research the innovative mechanism and system architecture of the network security supervision of power grid enterprises from the aspects of management and technology. Based on the new requirements of Classified Protection 2.0, this paper proposes a network security inspection evaluation system to help grid companies build new lines of network security.
Numerical simulation of in-cylinder combustion characteristics of LNG-diesel dual-fuel engine
Authors: Wang Jun , Chen Jing Sheng , Chen Hao , Hou Yu , Lin Xiao Long 
Published: February 2021

Abstract
Three - dimensional numerical simulation of diesel engine cylinder combustion process was carried out by using computational fluid Dynamics (CFD) software AVL-FIRE. The combustion characteristics of LNG under different ignition diesel ratio, cylinder pressure were studied. Through the simulation calculation of pilot diesel ratio, cylinder pressure, combustion heat release rate, the analysis results showed that the minimum value of pilot diesel ratio was not less than 0.5. During a cycle, there was no cliff-like change in cylinder pressure. CFD simulation has guiding significance for optimizing combustion chamber structure parameters and improving diesel engine performance. CFD simulation is instructive for the optimization of diesel engine performance.
Working Fluids Optimization Based on Economical Performance and Thermodynamic Performance for 350kW ORC System
Authors: Wei Lihong , Jiang Hua , Guo Ruiling , Zhang Haorui 
Published: February 2021

Abstract
This paper established a 350kW level organic Rankine cycle(ORC) system with the 393.15K flue gas as heat source. Nine kinds of working fluids were selected based on comprehensive consideration of thermal physical properties, environmental performance and safety. The optimum one was selected from them by comparing and evaluating their thermodynamic performance and economic performance at different evaporation temperatures. The results show that the thermal efficiency of system using R236fa increased firstly and then decreased with the increase of evaporation temperature, while the exergy efficiency and economic performance increase gradually. The thermodynamic performance and economic performance of others increased with evaporation temperature increasing. When the exergy efficiency was taken as the evaluation index, isopentane was the best working fluid. However, the thermal efficiency, levelized electricity cost(LEC) and discounted payback period(DPP) of the system using butane better than others. Therefore, butane is considered to be the most appropriate working fluid for this system among the nine working fluids.
A high-efficiency micro-grid simulation system based on STM32
Authors: Chen Weixin , Li Xue , Ai Huangze 
Published: February 2021

Abstract
A high-efficiency micro-grid simulation system based on STM32 is designed. The hardware circuit includes two three-phase half-bridge inverter circuits, AC voltage and current sampling circuits, and LC filter circuits. STM32F407 is used as the main controller, and outputs SVPWM waves. The main inverter has low THD when running on its own, so that can stably convert DC power into three-phase AC power. When working in parallel, the system realizes that the output power ratio of the two inverter circuits is adjustable. Through theoretical analysis and testing, the micro-grid has high efficiency, and the circuit also performs well when testing the load regulation rate. In addition, the system uses OLED screens and matrix keyboards to achieve human-computer interaction, and has overcurrent and overvoltage protection functions.
Frequency-Voltage Characteristics Concerned Optimal Dispatch
Authors: Xin Chaoshan , Fu Gaoshan , Meng Xianzhen , Tian Shoutao , Jing Shibo , Zhang Bo , Sun Donglei 
Published: February 2021

Abstract
The rapid development of integrated wind power bring serious challenges to power system operation. In order to address the increasing wind power curtailment problem, the frequency-voltage characteristics concerned optimal dispatch for power system with large-scale wind power integration is proposed in this paper. Through integration of the optimization of frequency characteristics and voltage characteristics into the traditional power system economic dispatch model, the flexibility resources of generation side and load sides in power systems are mobilized to promote large-scale wind power accommodation. The formulated frequency-voltage characteristics concerned optimal dispatch mathematical model is a nonlinear programming model, which is solved by the GAMS platform. The numerical analysis for an actual provincial power grid indicates that the proposed frequency-voltage characteristics concerned optimal dispatch method can promote wind power utilization efficiency and improve the economy of power system operation.
Re-Fracturing Technology Research and Application for Low Permeability Reservoirs in Huabei Oilfield
Authors: Ning Mengmeng , Jia Jiangfen , Guan Shaojie , Wang Peng , Liu Yang , Huang Bohua , Liu Qilun , Kong Weizhong 
Published: February 2021

Abstract
The research on the mechanism of repeated fracturing fractures shows that the pressure drop caused by the initial fracturing fractures and the production activities of the oil layer in the repeated fracturing wells leads to changes in the stress field near the well, which causes the fractures to re-fract during the repeated fracturing process. Combining with the low permeability characteristics of Tongxi fault block reservoir in North China Oilfield, optimization of repeated fracturing parameters and selection of fracturing materials were carried out, and the principle of well selection and layer selection was put forward. The repeated fracturing technology was successfully implemented in the Tong47-43x well and achieved a good oil-increasing effect, which provided important technical measures for the next development of the Tongxi fault block reservoir.
Research on life cycle cost control model of prefabricated building based on system dynamics
Authors: JIANG Jingsi , SUN Shusheng 
Published: February 2021

Abstract
This paper takes BIM as the platform and system dynamics as the research method, establishes the life cycle cost control model of prefabricated buildings, draws causality diagram and flow inventory diagram by Vensim software, obtains the main influencing factors of assembly building cost control, and then gives the cost control measures. In this paper, BIM, prefabricated building and system dynamics are combined to study the cost control of prefabricated building from a new perspective, and reasonable suggestions are given to provide new ideas for promoting the development of prefabricated building in China.
Comparative Analysis of the Construction and Operation Status of Hydrogen Refueling Stations at Home and Abroad and the Classification of Hydrogen Refueling Stations in GB 50516-2010 "Technical Specifications for Hydrogen Refueling Stations”
Authors: Pan Ke , Xu Bingsheng , Wang Bo , Jin Chenhong , Hou Shan 
Published: February 2021

Abstract
This paper reviews and compares the construction and operation of hydrogen refueling stations in China, Japan, South Korea, and Europe, etc. This paper also analyzes the classification of hydrogen refueling stations in the current GB 50516-2010 “Technical Specifications for Hydrogen Refueling Stations” and puts forward suggestions for improvement. Reviews and reflections on hydrogen standardization of China have been made in this paper based on standardization status of hydrogenation station.
A novel composite coupling mechanism base on nested wrapped for dual exicitation IPT system
Authors: You Anhong , Dai Xin , Gao Ruozhong 
Published: February 2021

Abstract
The traditional research based on dual-excitation wireless power transfer system(DES), its theoretical analysis is mostly based on the situation that the mutual inductances of the two primary coils and the secondary coil are equal. When the secondary coil is mismatch, the output powers of the inverters are different due to the difference of the mutual inductances between the two primary coils and the secondary coil, which affects system reliability. This paper designs a coupling mechanism with internal and external nesting, no matter where the secondary coil is located, the mutual inductances between the secondary coil and both the primary coil are the same. Compared with the single excitation system(SES), in the case of the same input voltage, the output power is increased by 4 times, and the stress of the switching component can be effectively reduced under the same output power. The feasibility of the proposed method is verified by simulation and experiment.
Study on novel structure of molybdenum 2-aminopyridine complex: (C5H7N2)2(Mo7O24)(H2O)4
Authors: Liu Haixing 
Published: February 2021

Abstract
A new molybdenum 2-aminopyridine complex (C5H7N2)2(Mo7O24)(H2O)4 is prepared by a hydrothermal reaction and the crystal structure has been determined by means of single-crystal X-ray diffraction. The Mo atom is coordinated by six O atoms. The crystal packing is stabilized by O-H…O and O-H…N hydrogen bonding interaction.
Verification of Rapid Determination of Coal Seam Permeability Coefficient Based on COMSOL
Authors: Bingrui Li , Shubo Li 
Published: February 2021

Abstract
To verify the accuracy of the calculation method based on the indentation-pressure drop method to quickly determine the coal permeability coefficient, this paper simulated the gas pressure change curve of the borehole based on the COMSOL numerical simulation software. The pressure change curve obtained by setting different air permeability coefficients in the simulation software, combined with the rapid determination of the coal permeability coefficient calculation method to calculate the coal permeability coefficient, and the error between the simulated value and the calculated value is compared. The results show that the relative error between the simulated value and the calculated value is -23%~+45%, and the error between the calculated result and the simulated parameter is small, which verifies that the method of quickly determining the coal permeability coefficient based on the indentation-pressure drop method is correct and feasible. The simulation results show that the calculation results of the pressure curve obtained by the short-term simulation and the long-term simulation are basically the same. Therefore, the short-term measurement results can also be used to calculate the coal seam permeability coefficient. The rapid determination of the coal seam permeability coefficient is theoretically feasible.
Synthesis of the VPEG Polycarboxylate Superplasticizer with Controllable Activity and Its Properties
Authors: Chen Wenhong , Deng Lei , Jiang Yu , Li Jianmei 
Published: February 2021

Abstract
This paper focuses on the synthesis of a kind of VPEG polycarboxylate superplasticizer with controllable activity with 4-hydroxybutyl vinyl polyoxyethylene ether (VPEG), acrylic acid (AA) and fumaric acid (FMA) as the main raw materials. Through the experimental results, it can be found that the optimum process conditions are as follows: the water-reducing admixture has ideal fluidity and workability in concrete, with the temperature of 20°C, the reaction system concentration of 40%, the mass ratio of acid to ether of 9.2%, and the initiator and the chain-transfer agent respectively accounting 0.3% and 0.09% of the total mass.
Study on the Preparation and Performance of Hexa-carbon Polycarboxylate Superplasticizer with High Workability
Authors: Deng Lei , Chen Wenhong , Jiang Yu , Li Jianmei 
Published: February 2021

Abstract
In this paper, 4-hydroxybutylvinyl polyoxyethylene ether (VPEG), methacrylic acid (MA) and methylene phosphate (MEPA) are used as main raw materials to synthesize a hexa-carbon polycarboxylate superplasticizer with high workability under the action of an iniator. The test results show that the superplasticizer has high water-reducing rate and good slump-retention, and its workability is greatly increased, which can be used in practical concrete projects that have high requirements.
Preparation of cuprous iodide transparent thermoelectric materials by SILAR method
Authors: Chen Shuai , Zhou Fan , Wei Kun , Chen Naichao , Zhong Minyong , Zhao Jin 
Published: February 2021

Abstract
Thermoelectric generator can obtain electric energy from waste heat, which is one of the best ways to recycle the energy from waste heat. At present, most thermoelectric materials tend to be opaque, so the preparation of transparent thermoelectric materials is one of the research directions of thermoelectric materials. In this work, p-type transparent CuI films were prepared by successive ionic layer adsorption and reaction (SILAR) method. The crystalline structure of the film was determined to be γ-CuI by X-ray diffraction. The surface morphology of the film analyzed by scanning electron microscope was flat. In the wavelength of visible light, the average transmittance of CuI film is 60-70%. The energy band of the prepared CuI film is calculated by the formula to be about 3.04 eV. The results show that the CuI film prepared by the SILAR method has excellent optical transparency.
Noise source identification in indoor substation using a sparse equivalent source method
Authors: Xu Luwen , Yang Bo , Wang Haitao , Zhang Lin , Nie Yaocheng 
Published: February 2021

Abstract
Noise source identification is a key step in the noise control design of the transformer. The sound propagation is influenced by the reverberation effect in the indoor substation, which leads that the traditional method cannot give correct results in such environment. To supress the reverberation effect, a sparse equivalent source method is proposed to realize the noise source identification in indoor substation. This method first establishes the indoor sound transfer function model between the equivalent source surface and the acquisition surface by using wave simulation. Based on the wave simulation and combined with the sound pressure sampling data, the distributed equivalent source is recovered on the equivalent source surface by sparse recovery algorithm, and finally the sound pressure reconstruction on the reconstruction surface is realized. The numerical verification demonstrates that this method is capable of extracting the real noise information in the reverberation sound and giving the real noise source distribution result. This method can be used as an effective method in the noise source identification in the indoor substation.
Research on the effect of UHMWPE cavity protection board on rapid enhancement of wall anti-blast performance
Authors: Wu Xicheng , Tang Baijian , Li Hongming 
Published: February 2021

Abstract
In view of the high cost and self-importance of traditional explosion-proof walls, a fiber composite material cavity protective board made of UHMWPE as a matrix is proposed to protect the walls of general civil buildings to achieve rapid enhancement in response to sudden terrorist attacks. Based on LS-DYNA finite element analysis, the response of the protective board and wall under the impact of the explosion is analyzed. By setting different key parameters such as equivalent weight, burst distance, presence or absence of protective structure, the damage to the wall, the protective effect of the protective board and its own performance characteristics are discussed. The results show that the externally arranged composite material protection board can effectively attenuate and absorb the overpressure and energy generated by the explosion shock wave, and significantly reduce the displacement and deformation of the wall, and it also has excellent performance in its own energy absorption and deformation resistance. But there is a certain safety protection distance under different equivalents.
Study on the occurrence law of gas in Fukang mining area
Authors: Li Chengyu , Zhang Lili 
Published: February 2021

Abstract
Fukang mining area consists of three sections: Urumuqi He-Sigong He, Sigong He-Baiyang He and Baiyang He-Dahuangshan. Typical high-gas mines are taken in the three sections to measure the content of coal seam gas, analyze the occurrence law of gas in Fukang mining area, predict the amount of gas in mining period, and provide the basis for the prevention and control of mine gas.
Separation/enrichment of Nickel(II) using Potassium Bromide-PAN-Phenolphthalein System
Authors: Wen Xinrong , Tu Changqing 
Published: February 2021

Abstract
Separation/enrichment of nickel( II) using potassium bromide-PAN-phenolphthalein system is reported. Various factors affecting the separation/enrichment of nickel( II) are studied, the separation/enrichment of nickel( II) mechanism is deduced. The results show that by contolling pH 6.0, the chelate precipitate of Ni( II)- PAN formed form nickel( II) and PAN could be adsorbed on the surface of microcrystalline phenolphthalein to form liquid-solid phases with a clear interface under the best conditions, while Mn2+, Zn2+, Al3+, Cu2+ and Cd2+ are not adsorbed in this condition. So, the separation of Ni2+ form these metal ions is achieved. The method for the separation/enrichment of trace nickel is established. This method was applied to the quantitative separation/enrichment of trace Ni2+ in synthetic water, and the results are satisfactory.