bluuebunny/crossref_metadata_2025_split huggingface dataset:
Research on parallel output method of DC regulated power supply
Authors: Yan Xu , Li Meng , Wang QiYue , Liu He , Zhang XiaoMing , Zhang Yue 
Published: March 2022

Abstract
This paper describes the output characteristics of DC regulated power supply in spacecraft ground test system and proposes a scheme of DC regulated power supply parallel output with remote sampling. Then the power-on and power-off procedure as well as the characteristics of normal operation in space vehicle using ground power supply are analyzed.The transient characteristics of parallel power supply are summarized. This method with simple circuit connection is able to meet the power supply requirements of spacecraft as well as improve the reliability and security of power supply system. Experimental verification demonstrates the effectiveness of the proposed method. It solves the problem of heavy load energy requirement of spacecraft in ground test and verification stage.
Design and Verification of an Electro Hydrostatic Brake System
Authors: Zhao Jia , Chang Kai , Ru Fen , Xie Yan , Li Wei 
Published: March 2022

Abstract
Electro-Hydraulic Actuation is a distributed power telex technology which integrates machine, electricity and liquid as one. A miniaturized Electro-Hydraulic Brake System is designed by introducing Electro-Hydraulic Actuation Technology into aircraft Anti-skid Brake System. It can transmit power by electricity in brake system. Firstly, the mathematical model of the Electro-Hydraulic Braking System is established. Secondly, the semi physical simulation of the hardware in the loop is completed in the real-time simulation platform to verify the anti-skid braking control function of the system, realize the parameter optimization process, and determine the important parameters, so as to provide guidance for the production of the sample. Finally, the correctness and function of the Electro-Hydraulic Brake System are verified by the test on the inertial platform. The results show that the system can achieve the expected anti-skid braking function, and can provide support for subsequent engineering.
Application of aluminum alloy in aircraft
Authors: Wu Yue 
Published: March 2022

Abstract
From the perspective of aircraft manufacturing industry, aluminum alloy is a material with high practicability. It has the advantages of simple process, convenient processing, good forming performance, high durability and reliability, convenient maintenance, taking into account a series of advantages such as corrosion resistance, high strength, high stiffness and low cost. Applying it to the aircraft manufacturing industry can not only effectively control the cost of aircraft manufacturing, but also give full play to the material properties, improve the service performance of various aircraft components, improve the aircraft manufacturing level, and meet the development needs of the aircraft manufacturing industry. Based on the application case of aluminum alloy in aircraft, this paper studies the application of aluminum alloy in aircraft, and then puts forward the existing problems and solutions of aluminum alloy in aircraft, in order to provide valuable reference for the development of material field and aircraft manufacturing field in China.
Research on interference fit of high-lock bolts based on finite element simulation
Authors: Feng Yu 
Published: March 2022

Abstract
Firstly, the finite element simulation of high-lock bolt pressing into single-layer plate is carried out based on ABAQUS,and compared with the theoretical calculation results which are derived from the elastic-plastic mechanics.It illustrates that the validity of the finite element model.Finally, the life-death unit technology of ABAQUS is used to analyze and compare the stress state of hole wall, the HST10AG6 high-lock bolt hole is wrongly installed by HST110AG6 high-lock bolt. It is considered that it is appropriate to expand the hole and install the HST10AG8 high-lock bolt.
Study on plasma combustion process in aero engine combustor
Authors: Wang Tianyu , Yu Jinlu , Zhao Bingbing , Cheng Weida , Zhang Lei , Sun Yongkun 
Published: March 2022

Abstract
In order to explore the effect of plasma combustion on the performance of aeroengine combustion chamber, a simplified 9-Step plasma reaction mechanism was added to the 16 component 25 step reaction mechanism of aviation kerosene, and a kerosene combustion chemical reaction process model considering the excited state relaxation reaction of plasma electron collision reaction and the chemical reaction involved in excited state was established, The numerical calculation of combustion process in combustion chamber was carried out, and the numerical calculation results of combustion process with and without plasma combustion support were compared and analyzed. The results showed that after adding plasma in the combustion chamber, the active particles produced by plasma reaction made kerosene burn more fully in the main combustion zone. Under the appropriate chemical ratio, the average temperature of the outlet section of the combustion chamber increases from 2208.5K to 2543.5K, and the combustion efficiency increases by 11% to 95.6% on the basis of 84.6%; The outlet temperature field was more uniform, and the temperature distribution coefficient (OTDF) was reduced from 0.131 to 0.111, which improved the performance of the combustion chamber.
Research on the Scheme of Variable Thrust Solid Rocket Motor
Authors: Yin Yongqi , Zhou Wei , Ma Peiyang , Ma Qingzhuang , Shi Xueqian 
Published: March 2022

Abstract
The solid rocket motor is extremely widely used due to its many advantages, but the solid rocket motor also has the disadvantage that the thrust cannot be changed. To solve this problem, there are generally two solutions to this problem. One is to use a mechanical pintle structure to change the effective cross-sectional area of the nozzle, and then to change the size of the thrust. The other is to change the effective cross-sectional area through the secondary jet method. These two methods all can change the size of the thrust, but they also have their drawbacks. The domestic team proposed a plan that combines the two methods to make up for each other’s shortcomings.
Numerical Simulation of Wind-induced Swing Angle of 1000kV Transmission Line Suspension Insulator Strings Considering Dynamic Response
Authors: Feng Zhihui , Li Tao , Zheng Lei , Li Jian 
Published: March 2022

Abstract
The wind-induced swing angle of insulator strings directly affects the electrical insulation performance and the construction cost of the UHV transmission project. However, due to not considering the fluctuating wind pressure, the calculation results of wind-induced swing tend to be conservative when adopting the recommended guidelines of standard especially in the face of severe weather. This paper simulates the transient wind field of strong winds based on time-space correlation characteristics and constructs the fluctuating wind load distribution model exerting on the UHV transmission line. Then a refined finite element model of the multi-span transmission line including the entire tensile section is established. And the swing angle of the insulator strings calculation formula is fitted based on the calculation results of the wind-induced swing response. The calculation result shows the swing angle decreases with the increase of ice thickness, and the magnified coefficient of the wind-induced swing angle at the target tower under the basic wind speed of 15m/s is 1.03.
Spatial Load Prediction of Urban Distribution Grid under the Low-carbon Concept
Authors: Zheng Zhen , Jiang Chen , Zhang Guanhua , Han Wanli , Liu Jiale 
Published: March 2022

Abstract
Under the goal of “dual carbon”, distribution grid is the basic platform serving the country to achieve carbon peak and carbon neutral goals, and spatial load prediction is of great significance to the planning and construction of distribution grid. To improve the accuracy of the spatial load prediction of the distribution grid, this paper proposes an algorithm based on the ELM (Extreme Learning Machine), using the parameters of the particle group optimization model. Through the simulation experiment of the searched data, the relative error of the FCM algorithm, the PSO optimization algorithm has high accuracy and meets the requirements of practical engineering.
Design and Application of Intelligent Patrol System in Substation
Authors: Zhang Shun , Zhang Yankai , Cao Shibao , Li Biao , Qi Xiangmeng , Li Shengpeng 
Published: March 2022

Abstract
With the continuous development and improvement of power grid technology, intelligence has become the development goal of power grid technology. By designing an intelligent substation inspection system, simplifies the operational tasks of inspectors, and makes inspection of power equipment more accurate, efficient, and traceable. In the implementation of the system, the mobile terminal is responsible for the collection, input, and upload of inspection data, and the server completes the data reception and statistics and displays it visually. And the application of the case proves that the intelligent patrol system is convenient and quick to operate, the social and economic benefits produced are significant, and it has strong practicability.
Research on Frequent Failures of Pilot Solenoid Valve of Emergency Diesel Engine in Nuclear Power Plant
Authors: Fu Jiang , Pan Weiwei , Qin Qiang , An Kang , Wang Meng 
Published: March 2022

Abstract
The working pressure of the start-up compressed air pilot solenoid valve is 40bar when it starts, it is an important part of the emergency diesel air start system of nuclear power plants. Since the operation of the nuclear power plant, it has been found that the start-up compressed air pilot solenoid valve has more frequent failures, the failure modes are air leaks and jams. The start-up compressed air pilot solenoid valve are all solenoid valves of the same type, the manufacturer is MABO, the model is MV320V DN20 G34 NC. Once the start-up compressed air pilot solenoid valve fails, it will affect the reliability and availability of the diesel engine’s start-up air system, directly cause the diesel engine to fail to start. Through a series of tests, the jamming and air leakage failures in the use of the start-up compressed air pilot solenoid valve are tested and analyzed. The reasons for the frequent air leakage and jamming of the starting compressed air pilot solenoid valve are determined, effective improvement plans are proposed, such as changing to another type of grease, adding the solenoid spool guide ring and return spring, improving the spool structure, increasing the diameter of the pilot valve and coil power, etc.. After analysis and demonstration, it is further clarified that the reasons for the leakage and jamming of the pilot solenoid valve are clear, the improvement plan is effective. The results show that the improved program obtained through research has laid a foundation for solving the problem of frequent leakage and jamming of the pilot solenoid valve.
Research on open source platform of digital power grid based on CEPH open source distributed storage technology
Authors: Liang Jinzhao , Chen Haomin 
Published: March 2022

Abstract
In order to ensure the operational quality of open source platform and improve the security of power grid information management, a research method of digital power grid open source platform based on CEPH open source distributed storage technology is proposed. The open source platform structure of digital power grid is optimized by using the operation of object to block mapping and human-computer interaction function of CEPH platform. CEPH open source distributed storage is used to optimize the information management function of digital grid open source platform and improve the effect of grid data and information sharing. An adaptive quantization strategy is designed to dynamically determine the load factor weightthe weighty of load factor of the digital grid open source platform and improve the resource storage performance of the platform. The test results show that the digital grid open source platform based on CEPH open source distributed storage technology has low memory occupancy, data processing of high efficiency and good system load balancing ability, which meets the needs of information security and data processing of the digital grid open source platform.
Three-dimensional culture and chondrogenic differentiation of mesenchymal stem cells in interconnected collagen scaffolds
Authors: Xie Yan , Sutrisno Linawati , Yoshitomi Toru , Kawazoe Naoki , Yang Yingnan , Chen Guoping 
Published: March 2022

Abstract
Interconnected scaffolds are useful for promoting the chondrogenic differentiation of stem cells. Collagen scaffolds with interconnected pore structures were fabricated with poly(lactic acid-co-glycolic acid) (PLGA) sponge templates. The PLGA-templated collagen scaffolds were used to culture human bone marrow-derived mesenchymal stem cells (hMSCs) to investigate their promotive effect on the chondrogenic differentiation of hMSCs. The cells adhered to the scaffolds with a homogeneous distribution and proliferated with culture time. The expression of chondrogenesis-related genes was upregulated, and abundant cartilaginous matrices were detected. After subcutaneous implantation, the PLGA-templated collagen scaffolds further enhanced the production of cartilaginous matrices and the mechanical properties of the implants. The good interconnectivity of the PLGA-templated collagen scaffolds promoted chondrogenic differentiation. In particular, the collagen scaffolds prepared with large pore-bearing PLGA sponge templates showed the highest promotive effect.
Bioinspired TiO2/chitosan/HA coatings on Ti surfaces: biomedical improvement by intermediate hierarchical films
Authors: Rahnamaee Seyed Yahya , Ahmadi Seyedkhani Shahab , Eslami Saed Aylar , Sadrnezhaad Sayed Khatiboleslam , Seza Ashkan 
Published: March 2022

Abstract
The most common reasons for hard-tissue implant failure are structural loosening and prosthetic infections. Hence, in this study, to overcome the first problem, different bioinspired coatings, including dual acid-etched, anodic TiO2 nanotubes array, anodic hierarchical titanium oxide (HO), micro- and nanostructured hydroxyapatite (HA) layers, and HA/chitosan (HA/CS) nanocomposite, were applied to the titanium alloy surfaces. X-ray diffraction and FTIR analysis demonstrated that the in situ HA/CS nanocomposite formed successfully. The MTT assay showed that all samples had excellent cell viability, with cell proliferation rates ranging from 120% to 150% after 10 days. The HO coating demonstrated superhydrophilicity (θ ≈ 0°) and increased the wettability of the metallic Ti surface by more than 120%. The friction coefficient of all fabricated surfaces was within the range of natural bone’s mechanical behavior. The intermediate HO layer increased the adhesion strength of the HA/CS coating by more than 60%. The HO layer caused the mechanical stability of HA/CS during the 1000 m of friction test. The microhardness of HA/CS (22.5 HV) and micro-HA (25.5 HV) coatings was comparable to that of human bone. A mechanism for improved adhesion strength of HA/CS coatings by intermediate oxide layer was proposed.
Discrete Hamilton–Jacobi theory for systems with external forces
Authors: de León Manuel , Lainz Manuel , López-Gordón Asier 
Published: March 2022

Abstract
This paper is devoted to discrete mechanical systems subject to external forces. We introduce a discrete version of systems with Rayleigh-type forces, obtain the equations of motion and characterize the equivalence for these systems. Additionally, we obtain a Noether’s theorem and other theorem characterizing the Lie subalgebra of symmetries of a forced discrete Lagrangian system. Moreover, we develop a Hamilton–Jacobi theory for forced discrete Hamiltonian systems. These results are useful for the construction of so-called variational integrators, which, as we illustrate with some examples, are remarkably superior to the usual numerical integrators such as the Runge–Kutta method.
Environmentally sustainable socio-economic welfare and agricultural employment: evidence from ECOWAS
Authors: Umehruo C.H. , Owolabi O.A. , Aderounmu B. , Rotimi M.O. , Osabuohien E.S. 
Published: March 2022

Abstract
Environmental sustainability considerations in socio-economic welfare has been argued in recent welfare literature. With an emphasis on the role of agricultural employment, this present study explores environmentally sustainable socio-economic welfare in ECOWAS, which features countries abundant in agriculture resources, although with low levels of socio-economic welfare and low carbon emissions. The study utilises a balanced panel data set of observations in respect of all fifteen ECOWAS countries over the period of 2010 to 2019. The Human Sustainable Development Index (HSDI) was used to measure environmentally sustainable socio-economic welfare. On the other hand, agricultural employment was measured using the percentage of the employed population earning their livelihoods from agricultural employment. Panel data fixed effects estimation was used to estimate the model for the study, and the findings were that agricultural employment had a significant adverse influence on environmentally sustainable socio-economic welfare as measured by HSDI, while a further comparison of the findings with that of welfare measured using HDI indicated that agricultural employment also adversely affected HDI. The study recommends that socio-economic welfare be assessed from the view point of environmental sustainability, and the governments of ECOWAS member countries provide strong governance including strong laws and policies to ensure that socio-economic welfare that is environmentally sustainable is realised as abundant agricultural resources as well as agricultural employment are well managed.
Nitrous oxide variability and predictability in the tropics using statistical analysis
Authors: Ogunsola O.E. 
Published: March 2022

Abstract
Among the three most powerful long-lived greenhouse gases (CO2, CH4, and N2O) present in the atmosphere and affected by human activities, N2O has the longest atmospheric lifetime than the rest and a large global warming potential. Its impact is about 300 times that of CO2 which also has a life time next to it amongst these three long-lived gases. The presence of N2O has the potential effect of raising global temperature because of its ability to trap heat. Hence, it is necessary to predict its future concentration so as to know its possible trend. The analyses of these concentrations were carried out using descriptive statistics. The moving average was used in smoothening out its fluctuations in order for the trend to become apparent and the regression analysis was utilized in fitting the appropriate equations for predicting its concentration. The mean annual concentration value of this gas for the period 1998 – 2012 at the various stations consideredwas 319.09±0.63ppb with an average range of 11.98±0.23ppb.The comparison of the actual data with the modeled data showed high correlation coefficients and the polynomial function of order 1 (linear equation) is sufficient in predicting the concentrations of this gas if the current trend should continue.
Suitability and hydrogeochemical imprints of groundwater in residential location around Abeokuta, southwestern Nigeria
Authors: Academe S.O. , Emenike P.C. , Unokiwedi P. , Nnaji C.C. , Etim M.A. 
Published: March 2022

Abstract
Water quality evaluations of domestic wells are required to monitor its consumption suitability since its dependence is on an increasing rate in the study region. Therefore, the rationale for the study is to obtain the hydrogeochemical characteristics of water from domestic wells and their level of potability. In the current study, the hydrogeochemical footprints of twenty water samples obtained from deep wells located in residential buildings were analyzed for TDS, Turbidity, TSS, TH, Acidity, Alka, HCO3
−, CO3
2-, DO, NO2
−, NO3
−, SiO2, PO4
3-, SO4
2-, Br−, Cl−, F−, Ca2+, Fe2+, Mg2+, K+, Na+, EC and ranked using the entropy-based water quality index (EBWQI) to determine its drinking suitability.Water classification was achieved using hydrogeochemical facies and the ion exchange was obtained using biplots of important water quality parameters. The mean concentration of the water quality parameters mentioned above were 717.69, 46.11, 157.20, 224.81, 72.91, 64.06, 78.07, 0.01, 3.89, 0.89, 51.56, 16.50, 0.73, 32.87, 0.01, 174.41, 1.89, 58.91, 0.03, 19.41, 3.05, 72.82 mg/L and 1009.63 μS/cm, respectively. Benchmarking the results with the WHO 2017 standard, 10%, 85%, 10%, 45%, 20%, and 45% of the water samples surpassed the threshold for TDS, EC, DO, NO3
−, Cl−, and F−, respectively. The groundwater classification derived from the piper plot revealed 40% mixed type, 15% Na-Ca-Cl water type, 15% Na-Ca-Mg-Cl water type, 20% Ca-Na-Cl water type, and 10% Ca-Na-Mg-Cl water type, with Na and Cl dominating the hydrogeochemical facies. The geochemical activity governing the groundwater chemistry obtained from the plot of [Ca2+ + Mg2+] vs [HCO3
− + SO4
2−] showed silicate weathering and carbonate weathering in 5% and 95% of the water samples, respectively. Furthermore, the ion exchange activity based on [Na+ + K+ – Cl−] vs [(Ca2+ + Mg2+) – (HCO3
− + SO4
2–)], CAI-1 and CAI-2 plots supports reverse ion exchange. Generally, the chemical activities support rock-water and evaporation dominance within the sample location. The EBWQI ranking showed that 10% of the water samples are excellent, 20% are good, 40% are moderate, 10% are poor, and 20% of the water samples are abysmal for consumption. Therefore, the water situation in the study region requires adequate treatment strategies to foster healthy living for residents.
Electrical resistivity application for road failure assessment at an industrial hub in Ogun State, Nigeria
Authors: Okeniyi Elizabeth Toyin , Adagunodo Theophilus Aanuoluwa , Okeniyi Joshua Olusegun 
Published: March 2022

Abstract
This paper employs the geophysical surveying technique of two-dimensional electrical resistivity imaging (2D ERI) for gaining insights into the causes of incessant road failures being encountered at an industrial hub, along Idiroko Road, in Ota, Ogun State, Nigeria. These utilises occupation of three traverses, each of 100 m for the 2D ERI, constituting a control of a stable road portion, and a stable and unstable portions of a crucial turning along the dual carriage highway of Idiroko Road in Ota. The obtained 2D ERI measurements were rendered to the processing of the RES2DINV software for the derivation of the 2D resistivity inverse model. Results show that the portions of the roads that are stable exhibited higher values of apparent resistivity compared to portions exhibiting frequent road failures. Ensuing sub-surface layer characterisations by the 2D ERI revealed geo-electrical layers exhibiting permeable soil formations that allow water to percolate in the stable portion of the road while the unstable portion depicted presence of water in an impermeable soil formation. These engender recommendations for road construction durability issues that can culminate into system of sustainable road network at the studied industrial hub location in Ogun State, Nigeria.