bluuebunny/crossref_metadata_2025 huggingface dataset:
Study on Interior Ballistic Characteristics of the Multi-gas Sources Ejection Power System
Authors: Bai Jianqiang , Wang Taikun , Qiang Xinwei , Sui Jiuling , Li Pengyong
Published: August 2020

In this paper, the internal ballistics model of the multi-gas sources ejection power system is established, the internal ballistics characteristics are studied, and the launch process of a certain missile is calculated by using the internal ballistics equation, and the important parameters such as velocity and acceleration of the missile, pressure and temperature in the launch cylinder are obtained. Compared with the pure gas single power launch scheme, the multi-gas sources ejection power system can effectively reduce the missile overload, reduce the pressure in the launching cylinder and improve the energy utilization efficiency. The maximum acceleration of the missile is reduced by more than 50%, which makes the movement process of the missile more stable and the interior ballistic trajectory more accurate; the maximum pressure in the launch cylinder is reduced by more than 45%, which greatly improves the launch safety, and also provides conditions for the lightweight of the launch device.
Research on Plant Core, Patch Repair Method of Huizhou Traditional Architecture Timber
Authors: Li Yucheng , Wang Wei , Wang Xing
Published: August 2020

Huizhou traditional architecture design method of repair beams is one of the hot spots in the present study of ancient architecture. Based on the basis of a large number of data collection and on-the-spot investigation, research and combined with the national regulations of the traditional building repair method of reinforcement beams, analysis of the Huizhou traditional architecture in timber frame beams damaged reasons, summed up the ancient building timber strength, stiffness the degree of the calculation formula and the core of planting of Huizhou traditional architecture beams by the finite element method, the crack patching reinforcement method is analyzed by numerical simulation. The results show that: when the damaged section beam strength and stiffness, through strengthening after the renovation has been improved; through the core and damaged beams, crack patching reinforcement method after repair is to meet the requirements of the standard. Through theoretical calculation and numerical analysis of beams, the calculation results are consistent, repair reinforcement design verification of Huizhou traditional architecture wooden frame beams The feasibility and feasibility of this method can be used as a reference for the protection and renovation of ancient buildings in Huizhou.
Research on Influencing Factors of Unsafe Behavior of Prefabricated Building
Authors: Wang Xiaowen , Sun Yucheng , Liu Yan
Published: August 2020

There are obvious differences between the assembly construction method and the traditional cast-in-place construction. At present, the assembly construction technology and management standards have not been perfected in our country, and the acceleration of technology can create unparalleled cascades of benefits as well as new risks of catastrophe. Through a lot of literature research, this paper designs questionnaires including risk perception, convenience perception, managerial pressure, co-worker pressure, and judgement ability based on the theory of planned behavior, and conducts factor analysis on the collected data. Finally, based on the analysis results, corresponding management level factors, workers level factors and self-perception factors of unsafe behaviors in prefabricated buildings are proposed.
The Study of Intention to Apply Live Video Transmission System in Disaster Sites for Firefighters through UTAUT model
Authors: Chen Tsung-Yu , Chen Yi-Ching , Tsai Chia-Chou , Chou Chung-Chyi
Published: August 2020

With the rapid development of network technology, the live video transmission system (LVTS) has improved the work efficiency because of the visual communication combining both images and data. In order to strengthen the effectiveness of disaster prevention through instant communication, the Fire Department in Taiwan has used the “VVLINK” videoconferencing system to provide multi-functional online conferences, and even grasp on-site dynamic situation of disasters in the first time, and then giving order to the disaster relief site online. Here, a research about the application of LVTS system in disaster sites was carried out to study the intention for firefighters in Fire Bureau of Changhua County, Taiwan. In this study “behavioural intension (BI)” and “usage behaviour (UB)” on LVTS system are explored through the Integrated Technology Acceptance Model (UTAUT). In addition, moderate variables such as gender, age, experience and voluntary are needed to be considered. “Performance expectation (PE)”, “effort expectation (EE)” and “social influence (SI)” can affect BI to be very significant; BI and “facilitating conditions (FC)” can also affect UB. Questionnaire analysis was applied. The results show that PE, EE, and SI have a positive direct impact on BI, and BI also has a positive direct impact on UB. It was also found that the FC had a positive and direct impact on BI as well as SI impacting on UB. All the moderate variables have significant difference on each UTAUT categories.
Study on pollutant characteristics of different types of manure sludge drying condensate
Authors: Xuan Zhang , Hongguang Zhu , Yupeng Xu
Published: August 2020

In order to further study the characteristics of condensate contaminants generated during the drying of livestock manure and biogas residues, the three biogas residues were dried at different temperatures and at different time. The condensate produced in the experiment was collected and its pH, ammonia nitrogen and COD were measured. Exploring the effects of different temperatures and different times on the characteristics of condensate contaminants during the drying of manure sludge. And further comparing the characteristics of different types of biogas residue dry condensate. The results show that: the three biogas residue condensates are weakly alkaline; the three biogas residue condensates COD rises with the increase of drying temperature, the use of low temperature drying can reduce the organic content of the dry condensate; low temperature drying can significantly reduce Exhaust gas treatment load to prevent the loss of organic fertilizer efficiency; with the extension of the drying time, the NH3-N content of the dry condensate of pig manure and chicken manure biogas residues decreased, and the NH3-N content of the dry manure biogas residue dry condensate increased; comprehensive consideration of drying efficiency and drying for the characteristics of condensate. It is recommended that all three kinds of biogas residues be dried at 60°C at low temperature.
Human factors analysis of Kaohsiung 8′1 explosion accident based on HFACS-UP
Authors: Wei Zhen , Wu Le , Chen Chong
Published: August 2020

Human factor is one of the main causes of urban gas pipeline explosion accidents. In order to minimize the consequences of such accidents, it is crucial to distinguish the human factors. In the present study, The Human Factors Analysis and Classification System-Urban Pipeline (HFACS-UP) is established according to the characteristics of urban pipeline accidents. Then the HFACS-UP framework is used to identify the human factors of a pipeline explosion accident occurred in Kaohsiung, Taiwan. The results indicate that the routine violations, skill-based errors, intellectual limitations, technological environment, failure to correct problems, insufficient safety culture, organizational process vulnerability and insufficient government supervision are the main factors lead to the explosion accident. Finally, the prevention measures are proposed to ensure the safe operation of urban pipelines based on the analysis results.
Experimental investigation of turbulence characteristics in stirred tank with polymer as drag reducing agent using particle image velocimetry
Authors: Quan Qing , Chen Yiming , Gao Zhimin , Qi Xueyu , Wang Shouxi
Published: August 2020

The effect of polymer concentration on turbulence flow field was analyzed by particle image velocimetry inside a stirred tank. With the increment of polymer concentration, the velocity gradient in the radial direction increased and the TKE and EDR rapidly decreased in the impeller region, while the velocity gradient decreased in the axial direction and the TKE and EDR first increased and then decreased in the region close to the wall. Higher polymer concentration resulted in lower turbulence intensity both in the radial and axial velocity components attributing to the weakened and restrained fluctuation intensity of the long-chain in the drag reducer polymer.
Perfluorohexane Sulfonate Decomposition In a High Photon Flux UV/sulfite System: Kinetics and Influential factors
Authors: Gu Yurong , Zhu Jia , Dong Zijun , Zhang Xi
Published: August 2020

Hydrated electron (eaq
-) is a strong reductant, and is reported promising for recalcitrant organic pollutants decomposition. In this study, eaq
- based decomposition of one representative short chain perfluorinated compounds, perfluorohexane sulfonate (PFHxS) in a high photon flux UV/sulfite system was investigated. The observed rate constant (kobs) of PFHxS was 0.028 min-1, which was one order of magnitude faster than that in previously studied UV/iodide system. UV intensity played an important role in the decomposition, when UV intensity was adjusted from 25% I0 to 100% I0, kobs of PFHxS decomposition increased from 0.010 min-1 to 0.028 min-. PFHxS decomposition efficiency was greatly enhanced in alkaline solution compared to that in the acidic solution.
Mechanism of migration and settlement for temporary plugging ball in shale gas horizontal wells
Authors: Zhang Feng , Li Kuidong , Xiao Jialin , Liu Wei , Hu Yun
Published: August 2020

In order to determine the migration and settlement mechanism of temporary plugging balls in horizontal wells, the rules for distribution, migration and settlement of balls in different location were researched through calculation, coupling fracturing fluid and characteristics of movement based on CFD (computational fluid dynamics), DEM (discrete element method) and DDPM (dense discrete phase model), and the intensity, plane and spatial distribution of the microseismic events before and after ball-addition were analysed. The results showed that: First, the central flow core in the pipeline is the main migration carrier of the temporary plugging balls and proppants, low-viscosity liquid performs differences when inflowing at various perforation holes. The settlement and plugging in downstream cannot be effectively improved while the upstream without balls’ settlement. Second, due to the fluid resistance, the mean velocity of temporary plugging balls decreases and balls spread along the casing wall while the interaction force can be ignored. Under different displacement, the temporary plugging balls’ migration speed has a relatively stable value, the displacement of 5 m3/min is the critical value for the effective setting of temporary plugging balls. Thus, most of the micro-seismic events after ball-addition were concentrated in the upstream clusters, the impact scope of the micro-seismic events of 6-clusters is greater than that of 8-clusters perforation. After ball-addition in 6-clusters, the key effect is to improve the complexity of the microfracture network, while in 8-clusters to improve SRV (simulated reservoir volume) for the beginning first 4 clusters. So that is, increasing the number of clusters will lead to an inadequate microfracture length extension and only SRV (simulated reservoir volume) near the wellbore zone was improved.
Study on the culture and degradation characteristics of dominant phenol-degrading bacterium for coal chemical wastewater
Authors: Peng-sheng Zheng , Zhong-quan Guo , Yan Xiao
Published: August 2020

To culture dominant phenol-degrading bacterium for bioaugmentation treatment of coal chemical wastewater, 3 phenol-degrading bacterium such as PDB-1, PDB-2 and PDB-3 were enriched and screened from activated sludge in the coal gasification wastewater treatment plant. The culture conditions such as temperature, pH and additional carbon source were analyzed. At last, the degradation effects of raw water were investigated. Results indicated that PDB-2 was the best bacterial strain with the strongest phenol-degrading ability. The degradation rate was 96.6% in 24 h under the initial phenol concentration of 400mg/L. The degradation rates were respectively 89.5% and 96.1% in 24 h and 36h under the initial phenol concentration of 800mg/L. Under the initial phenol concentration of 400mg/L, the dominant phenol-degrading bacterium grew best with the temperature of 30°C and pH of 7∼7.5, and 100mg/L or 200mg/L addition of glucose could further increase the 24 h degradation rate. When the preprocessed coal gasification wastewater was used to acclimate PDB-2, the total phenol and COD concentration of raw water were 18.2 mg/L and 193 mg/L with the corresponding 48h degradation rate of 95.8% and 92.5%.
Preparation and Catalytic Property of Au-decorated Titanium Dioxide Dendritic Nanofibers
Authors: Du Juan , Wei Aili , Shen Lulu , Chen Song
Published: August 2020

To remove organic pollutants from industrial wastewater, the Au-decorated titanium dioxide dendritic nanofibers (Au-Ti DNFs) were synthesized through in situ decoration of gold (Au) nanoparticles on the titanium dioxide dendritic nanofibers (Ti DNFs). The electrospun Ti NFs were firstly prepared by sol-gel method combined with electrospinning technology, then in situ converted to Ti DNFs in the NaOH solution via a hydrothermal route, and finally treated in the solution of HAuCl4.4H2O to produce Au-DTi NFs. SEM and TEM analyses showed that the Au-Ti DNFs had the dendritic and fibrous morphology and consisted of a large number of Au-Ti nanowires. 4-Nitrophenol was used as the model organic material to test the catalytic performance of Au-Ti DNFs. The results showed that Au-Ti DNFs catalytically reduced 4-nitrphenol to 4-amonphenol and their catalytic performance was higher than that of Ti DNFs due to the decoration of Au nanoparticles.
Study on Adsorption-Desorption of Benzene in Soil
Authors: Sun Jing , Lin Guoqing , Henghua Zhu , Tang Xiaomeng , Zhang Lichun
Published: August 2020

Groundwater near the Qilu petrochemical plant in Zibo City is polluted by oil for over thirty years, which seriously threaten the local ecological environment. The results of GC-MS analysis of water samples show that benzene was the most abundant and toxic organic pollutant. The adsorption-desorption behaviour of benzene in soil was studied through batch experiments. The results indicated that the adsorption amount of benzene in the local soil showed a trend of increasing first and then decreasing with the increasing of the initial concentration of benzene. There existed an optimal initial concentration of benzene in the adsorption experiments. The desorption concentration of benzene was proportional to the initial concentration of benzene. Particle size of the soil was inversely related to adsorption and desorption concentration of benzene. The soil with the average particle size of 0.08 mm had the largest adsorption capacity for benzene, which could reach 376.39 mg/kg. The results could provide a theoretical basis for the local groundwater remediation.
Effect of Combustible Gas Components on SNCR Reaction with Reducing Agent in Ceramic Kiln
Authors: Zeng Wenhao , Tang Zijun , Huang Jianhang , Tang Zhixiong
Published: August 2020

Selective non-catalytic reduction (SNCR) is a denitration method used in NOx process-control of ceramic kiln. In this study, the effect of combustion gas components (CO, H2, CH4) on NOx removal in the SNCR process was investigated, using ammonia and urea as reducing agent in a lab-scale experimental platform. The results showed that the addition of CO slightly promoted the NOx removal efficiency when ammonia was used as reducing agent, while when urea was used as reducing agent, the addition of CO inhibited the denitrification. The increase of H2 and CH4 addition ratio in the simulated flue gas reduced the de-NOx efficiency. With the same addition ratio, the effect of CH4 on the reduction of denitration efficiency was much more obvious than that of H2. When ammonia was used as reducing agent, the ammonia escape was much greater than that of urea.
Influence of flash evaporation on safety Characteristics of Liquid Hydrogen Leakage and Diffusion
Authors: Hu Yang , Zhao Huiping , Ma Yiwei , Xiong Yanyi
Published: August 2020

During the storage and transportation of liquid hydrogen, damage of pipeline or sealing failure of valve may cause liquid hydrogen leakage. The cryogenic and combustible hydrogen produced by the leakage are dangerous. Because the storage pressure is higher than atmospheric pressure, flash will occur in leakage accident, resulting in LH2 / H2 two-phase flow at the leakage port. In order to study the effect of flash evaporation on the hydrogen diffusion characteristics, the CFD method is used to simulate the liquid hydrogen leaking and diffusing process at different mass fractions of flash evaporation. The results show that the horizontal distance of combustible cloud diffusion is 15.6m when the liquid hydrogen leaking amount is 60L / min. When 14% liquid hydrogen flashes, the horizontal distance of hydrogen diffusion reaches 24.1m, and with the increase of flash evaporation, the horizontal distance increases significantly. With the increase of flash evaporation, the horizontal distance of cryogenic hazardous zone increased from 6.3m to over 9m. It can be concluded that flash evaporation has adverse influence on the safety after a liquid hydrogen leakage accident, which greatly increases the distance of combustible cloud dispersion and cryogenic hazardous areas.
Competitive adsorption characteristics of N2 and CH4 gas mixtures on coal and its geological significance
Authors: Xu Shuang , Wang Wei , Chen Xin , Li Yangbing , Fei Jingliang , Ma Litao , Du Linxuan
Published: August 2020

Coalbed methane (CBM) is an important unconventional natural gas resource and has achieved great advances in recent years. In this study, single and binary component adsorption experiments of N2 and CH4 on dry coal from eastern Yunnan and western Guizhou area were conducted on a high-pressure isothermal adsorption equipment to investigate the competitive adsorption characteristics of N2 and CH4. The results show that absolute adsorption capacity of methane is higher than that of nitrogen for coal samples in this area. Moreover, maximum mixture gas adsorption isotherms lie between the pure N2 isotherms and pure CH4 isotherms. There is an obvious increasing trend for PL as the content of nitrogen increases, it can be ruled out that critical desorption pressure increases along with the increasing nitrogen content in coal seam. This investigation is significative to understand CBM recovery processes considering N2 injection.
Effect of HVOF particle deposition angle on particle deposition behaviour
Authors: Zha Bailin , Jia Xudong , Wang Jinjin , Shi Yi’ang , Su Qingdong , Zhang Tianhao
Published: August 2020

Power particles are mainly in solid state prior to impact on substrates from high velocity oxy-fuel (HVOF) thermal spraying. The combination state of particles and substrate significantly affects the coating quality. Finite element analysis (FEA) models are developed to simulate the impingement process of solid particle impact on substrates under different deposition angles. This numerical study analyzes the deformation behavior of particles and the reason under different deposition angles, and the shear-instability– based method is applied to the particles. The particles are given the properties of widely used WC-Co powder for HVOF thermally sprayed coatings. The numerical results confirm that in the case of vertical deposition, the deposition behavior of particles is better than that of non-vertical deposition. In the case of non-vertical deposition, the equivalent plastic strain of the right part of the particle central axis is larger than that of the left part of the central axis, and decreases gradually in a clockwise direction. The flattening process of particles is mainly controlled by the horizontal drag force. When the normal velocity of particles exceeds the critical deposition velocity, the particles will appear adiabatic shear instability phenomenon, with the matrix to produce an effective combination.
Numerical Simulation of Reaction Efficiency of Vinyl Chloride Suspension Polymerization Reactor
Authors: Zhang Shuimu , Wang Jian
Published: August 2020

This paper establishes a mathematical method for calculating the polymerization process of industrial vinyl chloride suspension polymerization reactors. The polymerization rate, weight average molecular weight (WAMW), number average molecular weight (NAMW), monomer conversion rate and pressure are displayed throughout the reaction. Applying this model to existing experiment in the literature, the results are close. The final simulation results will be used to guide the industrial production of polyvinyl chloride (PVC).
Analysis of Anthocyanins in Different Parts of Michelia with High Performance Liquid Chromatography
Authors: Ma Zhiling , Tang Lizhu , Gao Xiaomin , Yan Chengming
Published: August 2020

In this paper, high-performance liquid chromatography was used to analyze the composition and content changes of anthocyanins in various parts of the ground in Michelia, such as flowers, leaves and stems. The results showed that its flower contained cyanidin and Petunidin, while the stem contained Pelargonidin and Peonidin, and no anthocyanins were detected in the leaves. The types of single anthocyanin components contained in different parts are different. It is intended to provide a reference for the cultivation and evaluation of new varieties of ornamental plants of Michelia.
Study on Mechanical Properties of Weakened Steel Frame Joints at Beam Ends
Authors: Ji Jing , Zhang Runbao , Li Zhihui , Xu Ming , Jiang Liangqin
Published: August 2020

In order to study the hysteretic properties of steel frame T-shaped weakened joints, 12 groups of steel frame weakened joints and 1 group of common joints are designed with the weakened form, the weakened diameter and the distance from the weakened center to the column end as the parameters. Based on simplified mechanical model and material constitutive relationship, the finite element model is established by ABAQUS software to analyze the hysteretic properties of the joint specimen. By comparing with the existing test results of the weakened joint, both have a good agreement, and the rationality of the finite element model is verified. The simulation analysis of the weakened joints of the beam webs is carried out in the further and the load-displacement hysteretic curves are extracted as well as skeleton curves and stress cloud diagram of the joints. The influence rules of the weakened form, weakened diameter and weakened distance from the center to the column end on the seismic performance of the joints are obtained, and the design suggestions for the weakened joints are put forward. These can lay a foundation for time-history analysis of the frame structure with this kind of joints.
Evaluation of bearing capacity of reinforced stone arch bridge based on dynamic load test
Authors: Hu Chuanwen , Luo Wenbo , Chen Shunchao
Published: August 2020

In order to evaluate the stress and working performance of a reinforced stone arch bridge, the load test of the bridge is carried out. Dynamic load test is used to test the inherent fundamental frequency, damping ratio and impact coefficient of the bridge through pulsation test and sports car test. Under the dynamic load, the first vertical natural vibration frequency of the bridge is 5.005, the damping ratio is 0.203, the second vertical natural vibration frequency of the bridge is 6.274, the damping ratio is 0.021, the tested strain impact coefficient is between 1.03 and 1.10, the measured vertical fundamental frequency is greater than the calculated fundamental frequency, and the overall stiffness of the bridge meets the design specification. The test results show that the reinforcement method of thickening the main arch ring has good application value, can effectively improve the service level of the old bridge and prolong the safety service life, and has obvious social and economic benefits.
Study on loading mode of upper arch Bridge under static load test
Authors: luo Wenbo , Hu Chuanwen , He Mao , Wang Lei , Wang Jianwei , Chen Shunchao
Published: August 2020

Bridge load test is a very important means to evaluate the structural performance, construction quality and bearing capacity of the completed bridge, among which static load test is a very important basis to judge the structural stiffness and bearing capacity of the bridge. However, the specification does not give detailed test method or suggestion for loading method of static load test of upper arch bridge. In this paper, based on the analysis results of field test data, a more reasonable loading method is obtained.
Data-driven Tracing Method of Overload of Transmission Network Equipment
Authors: Li Meng , Wu Wei , Lin Yi , Yan Tongyu , Huang Pingfa , Lin Shengyi
Published: August 2020

It is of great significance to the tracing of heavy load or overload (HOD) of power transmission network equipment for the precise investment and planning in power grid. The measurement system of power transmission network is increasingly accurate and intelligent, and a large amount of operation data was generated. Therefore, it is theoretically feasible for the tracing method based on big data is proposed for the HOD transmission network equipment. Firstly, the messy operation data generated by the power grid should be preprocessed, including data coding, cleaning and resampling. Secondly, estimation of the importance of independent variables of mutual information was solved out four characteristic quantities which have a great influence on HOD by game theory. Then, with the characteristic quantity as the label, the Fuzzy C-means (FCM) was used to cluster the HOD data into four categories, corresponding to four causes of HOD. Finally, an example is given to analyze the operation data of a city’s transmission network in 2019, which verifies the effectiveness and accuracy of the proposed method. Compared with the manual tracing method, the algorithm can greatly improve the efficiency.
Study on Optimal Operation for Concentrating Solar Power Plants Considering Wind Power Reduction
Authors: Yuan Guochun , Guo Panfeng
Published: August 2020

Concentrating solar power (CSP) generation units, which can generate electricity without any pollutant emissions, is one of the most attractive alternatives to fossil fuels. However, the main disadvantage of the CSP device is the high investment cost. In order to improve the economic feasibility, it is necessary to properly design the thermal energy storage (TES) device to optimize its economic benefits. In this paper, considering the operation requirements of power system, the optimal co-allocation model of solar energy field and TES device is established to weigh the investment cost and wind power reduction. Through a case study, the effectiveness of using energy storage to improve wind power consumption is verified on the basis of considering the constraints of the actual operation of the system, solar radiation and wind energy uncertainty.
Design of Fast Fault Diagnosis System for Transformer Equipment based on CBR and RBR
Authors: Hui NI , Xiaolu XU , Gong Hao , Luo Chuanxian , Zhou Zhengqin
Published: August 2020

After studying the common defects and faults of transformers, we design and propose a fast fault diagnosis system for transformer equipment based on CBR(Case-Based Reasoning) and RBR(Rule-Based Reasoning). In the system, test cases are firstly matched with the cases. If there are similar cases, CBR is used to obtain the diagnosis conclusion. If there are no similar cases, the rule reasoning module based on FTA (Fault Tree Analysis) is launched. This module subdivides transformer fault modes into winding, core, bushing, on-load tap changer, cooling system, non-electric protection and other fault modes, and forms rules. Based on this situation, a transformer equipment fault tree is established to serve the rapid diagnosis system. The structural characteristics and fault modes of transformer windings, iron cores, bushings, on-load tap changers, cooling systems, non-electrical protection and other equipment are subdivided. And then, a fast fault diagnosis model and system for transformer equipment are established. Finally, the case study proved that the system can diagnose and analyse the equipment faults based on the comprehensive multi-source data of transformers, and the diagnosis conclusion is reliable and practical, which has provided support for realizing the state maintenance of transformers.
Lightweight design and optimization of three-speed electric drive axle
Authors: Jin Di , Wang Zongze , Wang Jianhua
Published: August 2020

In order to provide wider speed range and smaller volume, wet multi-plate clutches and planetary gears are utilized to design a three-speed transmission system, electric drive axle housing is designed according to the transmission system. Aluminum alloy is used to perform lightweight design. Firstly, the finite element (FE) models of electric drive axle housing are built. Secondly the stiffness and strength simulation results of electric drive axle housing under different conditions are obtained. According to the simulation results, the thickness of electric drive axle housing is reduced and the stiffeners are added. The FE results show that the quality of the optimized shell is greatly reduced on the basis of the original stiffness and durability.
Study on Real-time Lithology Identification Method of Logging-while-drilling
Authors: Gang Chen
Published: August 2020

In geophysical exploration and development, lithology identification is the basis for understanding the strata and solving the reservoir parameters. Through the comparative study of three popular lithology identification methods including SVM, GRNN and Elman, each method in the experiments takes the same logging data as a sample to predict and identify, and the most suitable identification method is selected and applied to the automatic identification of lithologic interpretation. It is found that the prediction accuracy of SVM is highest in automatic lithology identification, and the method is suitable for computer automatic analysis in terrestrial interpretation system.
Analysis and Evaluation of the DC Magnetic Bias for 1000kV Ultra-High Voltage Transformer Caused by Changsha Rail Transit
Authors: Yuan Pei , Liu Yun , Li Xin , Xu Puming , Yan Ying , Hu Jinhao
Published: August 2020

In this paper, the stray current distribution network model of Changsha rail transit system is constructed from the perspective of the stray current induced by rail transit in the adjacent substation. We evaluated the degree of influence of the stray current of urban rail transit lines after the completion of the Changsha 1000 kV UHV substation, which provided a reference for the UHV transformer DC bias prevention experience.
Grid-connected Inverter Control Strategy Based On Capacitor Reference Voltage Feedforward
Authors: Xing Ning , Huang Hongquan , Chen Yanming
Published: August 2020

In view of the disadvantage that grid-connected power is not high and the phase margin of the grid-connected current is greatly reduced with the increase of impedance of many grid voltage feedforward control strategies. A grid-connected inverter control strategy based on capacitor reference voltage feedforward is proposed. In this control, the error between the filter capacitor voltage and its reference voltage is combined with the proportional controller as the inner loop control, the error between the inverter side current and its reference current is combined with the current controller as the outer loop control to improve the robustness of the system. The phase difference between grid-connected current and grid voltage is reduced by using capacitor reference voltage feedforward. In addition, by using the grid voltage resonance feedforward, the system can not only retains the ability to suppress harmonics, but also prevents the system’s phase margin from decreasing greatly under weak power grid. The proposed strategy has good dynamic performance, it can obtain good grid-connected current quality and high grid-connected power, and it has strong robustness to the change of LCL parameters and the fluctuation of grid voltag. At the same time, it has better adaptability to weak power grid.
Application of the technology about frequency conversion resonance in cable test
Authors: Jie Tang , Mei Cuizhi , Ming Guojin
Published: August 2020

According to the introduction about technology of the frequency conversion and structure of the device, In this paper, we know that the application of new reactor plays an important role in the test of XLPE cable and other equipment with operating voltage of 110kV and has high efficiency, we also elaborate characteristics of the test device about frequency conversion resonance combined with practical application.
Online detection method for inter-turn short-circuit fault of permanent magnet synchronous motor based on deep learning
Authors: Shi Chengji , Lu Xiaojuan
Published: August 2020

Aiming at the difficult problem of inter-turn short-circuit fault diagnosis of permanent magnet synchronous motors without stopping the machine, this paper takes timing anomaly detection as the starting point, and proposes an online fault detection method based on transfer learning deep self-coding network. First, a migration deep self-coding network model is constructed, and a combined sample of negative sequence current and electromagnetic torque is used to extract common features in different domains. Then, the online detection model of abnormal timing is established. Finally, the permutation entropy value of the normal state of the motor is used to construct an alarm threshold to improve the matching speed of abnormal sequences in the online data. Experimental results show that the method in this paperhas better detection practicality.
Design of an Input-Series Flyback Power Supply for Ultra-Wide Input Voltage Range Applications
Authors: Lin Yin , Liu Yahui , Guo Jiangtao , Ren Gaojian
Published: August 2020

In view of the inconvenient power taking, bulky volume, poor anti-fluctuation capability, high cost and complicated control of ultra-wide input-voltage mine-used power supply, a low cost design scheme of ultra-wide input-voltage power supply based on input-series flyback is proposed. The switching power supply scheme adopts conventional MOSFET to realize the self-adaptability under ultra-wide input-voltage range. In this paper, the circuit structure and working principle of mine-used power supply and the design of multi-channel synchronous pulse drive circuit are introduced in detail, and the feasibility of the circuit design is verified by experimental prototype. The experimental results show that the power supply scheme is not only simple in circuit design and low in cost, but also has the advantages of strong input-voltage adaptability, high conversion efficiency, good voltage sharing effect and the like, which is suitable for mining electrical equipment with multiple input-voltage levels.
Study on the Factors influencing the qualified Rate of Large Disturbances of the Primary Frequency Regulation on Heat Supply Units and the Improving Measures
Authors: Yu Qingbin , Sun Mengmeng , Li Yuanyuan
Published: August 2020

At present, the major problem faced by heat supply thermal power units is not only to ensure the external heating demand, but also to meet the requirements of the power grid for the primary frequency modulation of units. The main types of heat supply units in Shandong power grid are introduced. And take a 600MW pure condensing heat supply unit as an example, the reasons that affect the test results of large disturbance of primary frequency regulation in the period of heat supply are analysed. The scheme of optimization and transformation is put forward, which has good effect and meets the requirement of primary frequency regulation of power grid.
A Novel Oil-Water Two-Phase Flow Numerical Simulation Method In Tight Sandstone Reservoirs
Authors: Lei Zhanxiang , Zeng Baoquan , Wang Bin , Huang Fei , Xu Hui , Zhang Muzhen , Wu Shucheng , Qu Tailai
Published: August 2020

As a crucial factor affecting water flooding in tight sandstone reservoirs, dynamic capillary pressure (DCP) has significant impact on the production performance during oil-water flow. In this work, a novel numerical simulation method with DCP is developed to study oil displacement in tight sandstone reservoirs. Based on this new model, the impacts from DCP to water/oil displacement (or water flooding effects) are analysed. The results of this work show that the effects brought by dynamic capillary pressure cannot be neglected. The more significant dynamic effects of capillary pressure correspond to the sample with lower permeability. The effect of DCP is probably a major contributor to non-linear flow (non-Darcy flow) in tight sandstone reservoirs during water flooding process. Compared with the conventional flow theory (e.g., static capillary pressure theory), our derived model with DCP can help to reduce the uncertainty in water/oil flow in tight sandstone reservoirs.
Optimization Design Research of Deformation Control in Qingyuan Xinhe Garden Foundation Pit
Authors: Qiang Zhang
Published: August 2020

As there are many factors affecting foundation pit excavation and enclosure structure design, it is strongly necessary to carry out dynamic design and information-based construction, and to perform anti-analysis through monitoring information in deep foundation pit engineering. Taking Qingyuan Xinhe Garden foundation pit project as the engineering background and based on the deformation control optimization design theory, this paper analyzed the deformation of the foundation pit and the settlement volume of the surrounding buildings by combining on-site monitoring measurement and numerical simulation, which can provide an important reference for the safety and stability of foundation pit.
Research on Stress Monitoring Index of Hydraulic Tunnel Lining Based on Numerical Simulation
Authors: Zhu Junwen , Wang Zhaosheng , Li Dandan
Published: August 2020

In order to study the lining stress index of hydraulic tunnel, this paper mainly analyzes the safety monitoring data of a hydraulic tunnel, uses ANSYS finite element software for modeling, uses Flac 3D software for numerical calculation, and uses numerical analysis method to develop hydraulic tunnel G1 -18 Stress monitoring indicators for lining of section. The results show that the actual measured value is basically within the control range of the data calculation value. When determining the monitoring index of the steel bar stress, the result of the numerical calculation can be used as the index, but the monitoring index of the top steel bar meter should use the maximum monitoring value as the index.
Research on Incremental Distribution Network Operation Model Based on Cost-Benefit Perspective
Authors: An Lei , Tan Caixia , Wang Mianbin , Liu Xuan , Tan Zhongfu
Published: August 2020

In order to select the optimal mode of incremental distribution network and increase the revenue of the incremental distribution network, incremental distribution network cost-benefit model in three scenarios were established: non-sales company investment + operation, electricity sales company investment + operation, non-sales company investment + electricity sales company operation. At the same time, the three operating models are evaluated using three indicators: net present value, dynamic investment payback period, and net present value rate. Finally, take an incremental distribution network as an example to verify the effectiveness of the model. The result of the calculation example is that the electricity sales company’s investment + operation model has higher economic benefits than other models, the investment payback period is shorter, and the unit investment income is higher.
Research for Process on Investment Casting of Mouse Head Based on 3D Printing
Authors: Zhang Yue , Li Xue-Ying , Ma Chang-Liang , Xiao You
Published: August 2020

The rat head is selected as the object for the application of PLA 3D printed model in investment casting of alloyZL104. In order to optimize the process of casting, CAE analysis software AnyCasting is performed for the design of gating system. The top gating system shows the excellent casting results with little shrinkage defects. The solutions from simulation are conformed in the reality experience, which demonstrates that AnyCasting can provide accurate predictions of casting results, as well as reliability reference for the design of the process. Meanwhile, using the 3D printed rat head model for investment casting is practicable.
Performance Simulation of Plate Heat Exchanger Based on ANSYS ICEM
Authors: Yan-fei Li , Yan-wu Wang , Chao Du
Published: August 2020

A three-dimensional geometric model was established by ANSYS ICEM according to the structure of a plate heat exchanger. And the thermodynamic performance under different working conditions is simulated. The pressure field, temperature field, velocity field and flow pattern were analyzed based the simulated results. The heat transfer performance and resistance performance of heat exchanger under different flow rates and inlet temperature difference of cold and hot fluids are compared and analyzed. The results provide support for the more efficient use of plate heat exchangers under different working conditions.
Development and Application of the special drilling rig for oblique guide hole
Authors: Shu-jie Liu , Zhi-qiang Liu , Ji-wei Zhang
Published: August 2020

For the construction conditions of long-distance inclined drilling in roadway or chamber, a new type of self-moving hydraulic top-drive drilling rig is developed independently. Follow the research steps of the overall design, the key-parts design, the hydraulic system design, the industrial test. The main functional organization of the oblique-guide-hole drilling machine includes the power head, the feeding device, the power source, the drill pipe delivery installation, the rig control system, the hydraulic transmission system. The special oblique-guide-hole drilling rig realizes the construction requirement of any inclined drilling of 0∼90°, at the same time, it can meet the technical requirements of the directional drilling assembly, that is the combination of down-hole motor, non-magnetic drill collar and Wireless while drilling. The track of long-distance oblique drilling is precisely controlled. The field test of the special oblique-guide-hole drilling rig is at Changlongshan Pumped Storage Power Station in Zhejiang, China. The actual guide hole has an inclined length of 289.5m, and the deviation slope of the borehole is controlled within 2.86‰. It is successfully completed the anti-shaft guide hole in the lower section of the 1# diversion system high-pressure pipeline safely, quickly, and efficiently.
Kinetic Analysis and Optimum Design of Extracting Pectin from Pineapple Peel by Ion Exchange
Authors: Yanbo Gu , Bing Jiang
Published: August 2020

The pectin in pineapple peel was extracted by ion exchange method. The optimum conditions of pectin extraction were obtained by single factor and orthogonal test. Under the optimal process conditions, the kinetic model was constructed by Fick’s second law, and the rate constant and apparent activation energy were obtained. The validity analysis and the model prediction ability were verified. The results show that the kinetic model can predict the kinetic process of pectin extraction from pineapple peel by ion exchange method. According to the kinetic model, the optimal conditions were obtained: the dosage of ion exchange resin was 5%, pH was 2.5, the ratio of material to liquid was 1:30 (g: mL), the extraction temperature was 85°C, the extraction time was 141.7min, and the pectin yield was 9.74%, which was consistent with the results of single factor and orthogonal test.
Mass transfer simulation of main species in swine biogas slurry in bipolar membrane electrodialysis
Authors: Zhao Minqi , Chen Junjie , Zhu Hongguang
Published: August 2020

The aim of this model is to study the mass transfer of main species in swine biogas slurry in bipolar membrane electrodialysis. We developed a two-dimensional steady-state model composing three compartments. In this model, Nernst-Planck equation and Hagen-Poiseuille equation are combined for mass transfer and Faraday’s law is for the electrolyte current density. The model considers local electroneutrality condition and does allow cations and anions pass through membranes. The set of equations with boundary conditions and initial values are calculated by the finite element numerical method with COMSOL Multiphysics. This model can be able to predict the distribution of electrolyte potential, the ion flux and the ion concentration distribution. The two parameters, cell voltage and inlet velocity, are indicated to have influences on the process of bipolar membrane electrodialysis treatment on swine biogas slurry.
Gait planning and research of hexapod bionic robot based on bipedal injury
Authors: Xu Fenghui , Jia Yongxing , Zhou Zequan , Liu Xiaoqi , Wang Lei
Published: August 2020

Hexapod bionic robot plays an important role in battlefield reconnaissance and battlefield rescue. However, due to the complex battlefield situation, the robot’s legs are often damaged due to attacks, electromagnetic interference and other reasons, so it cannot work normally according to the original gait planning. In this paper, the damage situation of the hexapod bionic robot gait planning study, establish a foot injury cases six-legged robot model, USES the existing six-legged robot, combined with Matlab simulation model, build six-legged robot for foot injury under the condition of six-legged robot, simulation analysis is carried out under the different gait, planning out the suitable gait of robot movement. According to the analysis, the suitable gait under the condition of different injuries was obtained. This study can be used to improve the adaptability of hexapod robot in battlefield conditions and extend the working life of hexapod robot.
Study on the treatment of caprolactam wastewater by electrocatalytic oxidation process
Authors: Wang Tingfeng
Published: August 2020

Aiming at the caprolactam wastewater discharged from a chemical enterprise, the electrocatalytic oxidation technology was used for advanced treatment. When the current is 450A and the inflow flow is 3m3/h, the COD value of the effluent is reduced from 100mg/L to below 50mg/L, the ammonia nitrogen is reduced from 10mg/L to below 4mg/L, and the chroma is reduced from 50 times to below 30 times. The effluent quality meets the class A standard in Table 3 of 《Discharge standard of pollutants for municipal wastewater treatment plant》 (GB 18918-2002).
Intelligent design of street lamp based on Arduino
Authors: Liu Yuanchao , Zheng Kuncan , Liu Yuanhao , Wu Tao , Zhao Xudong
Published: August 2020

In order to promote the process of social modernization, the traditional street lamps are also moving towards intelligent development. However, the existing street lamps mostly use a single LED lamp or high-pressure sodium lamp, which can’t cope with the complex road conditions in China. The designer proposes to install the monitoring system on the street lamp, design the fine artificial intelligence light distribution and color temperature regulation scheme, add the functions of positioning, alarm, repair, pollutant and rain and snow monitoring, and realize the data interaction between the street lamp and the user and the manual intervention of the user when necessary through the infrared Bluetooth Internet of things and other technologies. The design is developed, simulated, debugged and tested on Arduino hardware and software platform. The results show that the design is reasonable and feasible.