bluuebunny/crossref_metadata_2025 huggingface dataset:
Developing POGIL-based worksheets of chemistry and unity of sciences
Authors: Zammi M , Khoiriyyah K , Wibowo T , Lathifa U , Fibonacci A
Published: March 2021

The development of POGIL-based worksheets of Chemistry and Unity of Science is an obvious step to reduce the existence of dichotomy on Students of UIN Walisongo Semarang. Media and Learning Sources used have not facilitated students in inquiry and UOS-contained activity. Therefore, the purpose of this research is to produce POGIL-based worksheets on Chemistry and unity of sciences and to decide the worksheets quality. Meanwhile this research method uses Research and Development with 4D by Thiagarajan. Validation sheets and Response Questionnaires are the instruments of Data Collection. The developed Worksheets are validated by material and media experts with the results of validation 89% and 88,33% in which the developed worksheets are valid and proper to be used. Otherwise, the response of students to the worksheets is good with the average percentage of questionnaire results 83,46%, the worksheets do not need to be revised. Hence, the proper-developed worksheets are used as the supported learning media for students.
Mathematical Study: The consumer price index in the expenditure sub group using factor analysis
Authors: Siswanah Emy
Published: March 2021

Inflation is very important monetary event and is often found in almost all countries in the world. In this research, it will be known what factors influence the inflation rate of Central Java in 2019. The method used is the Factor Analysis method with the Principal Component Analysis technique. Factor Analysis is one of the interdependent multivariate analysis techniques by reducing data to create a new variable (called a factor) and conducting an independent variable analysis into variables that correlate with other variables in the factor. The results of this factor analysis research, obtained two factors formed from 11 variables (expenditure sub-groups) with the largest contributor to inflation in Central Java in 2019. Factor 1 consists of Preserved Fish variable (X

1
), vegetables variable (X

2
), Fruits variable (X

3
), Seasonings variabel (X

4
), and Non-Alcoholic Drinks variabel (X

5
). Furthermore, this factor is named foods and beverages factor. Meanwhile, factor 2 consisted of Tobacco and Alcoholic Beverage variable (X

6
), Household Management variable (X

7
), Education Services variable (X

8
), Educational Equipment variable (X

9
), Courses/Training variable (X

10
), and Support Facilities for Transport variable (X

11
), was then given the name of the Tobacco, Services and Facilities factor.
Alternative ways to handle missing values problem: A case study in earthquake dataset
Authors: Fakhruddin Muhammad , Syazali Muhamad , Pradana Kenny Candra
Published: March 2021

Dataset is a basic foundation that is often used in understanding a problem. It provides information for researchers to get solutions to the problem. In the data retrieval process, some errors may occur and cause the data to be incomplete for any reason. It was a problem in how to recover the missing values in a dataset. The first step is to look at the characteristics of the data. In this paper, we proposed three alternative ways to obtain the missing values of the dataset. In this case, we used the earthquake dataset that has special properties. We then present the results to see the performance of the proposed methods. The results show a good agreement for the missing data. This is a preliminary result of our research related to missing data in the earthquake dataset. This study has some limitations such as if the missing values occur in a large enough data block, the methods need to be improved.
Synthesis and characterization microwave absorber properties of La0.7(Ca1-xSrx)0.3MnO3 prepared by Sol-Gel method
Authors: Admi R I , Saptari S A , Tjahjono A , Rahman I N , Adi W A
Published: March 2021

In this research, structural engineering of lanthanum-manganate-based material was studied, starting with material synthesizing La0.7(Ca1-xSrx)0.3MnO3 with variation of x=0; 0.1; 0.2; and 0.3 using the sol-gel method as a microwave material. The effects of Sr substitution on the stucture, size of grain, and microwave-absorbing properties were investigated in detail by various analytical methods. Using XRD (X-Ray Diffraction) showed that the sample had single phase and orthorombic structure (space group of Pnma), substitution of Sr2 + ions did not cause changes in structure. Characterized using SEM (Scanning Electron Microscope) showed change in grain size which increase when given Sr substitution. Characterized using VNA (Vector Network Analyzer) in the 8-12 GHz range shows that the sample La0.7(Ca1-xSrx)0.3MnO3 with x=0 has been able to absorb up to 55.64% microwaves at 10.44GHz. The study concluded the material of La0.7(Ca1-xSrx)0.3MnO3 have a good potential to be a candidate of microwave absorbing materials.
Inventory and identification of geodiversity to support geotourism in the Lenggoksono bay area of South Malang, Indonesia
Authors: Susilo A , Haji A T S , Suharto B , Sunaryo  , Suyadnya I W , Pramais C W , Rahman A H
Published: March 2021

Lenggoksono Beach Area which is a geomorphological region in the form of karst mountain located in the south of Malang Regency. This beach has beautiful scenery and presents unique and an interesting geosite conditions to be enjoyed. The purpose of this study is to inventory geodiversity data to fulfill the geotourism criteria and assess geodiversity data in the Lenggoksono Bay Area. The research method used was a survey and data collection method with 5 stages: data collection, criteria, assessment, interpretation, and clustering. The Lenggoksono Bay area has 5 landscapes, 4 beaches, islands, hills, and a river estuary. From the survey results, 6 types of rocks were found. Lenggoksono Bay was formed through the process of lifting the seabed containing limestone and coral reefs and igneous rock deposits over millions of years ago. These processes form the morphology and structure that has developed until present. The Lenggoksono Bay area has high value (4.4), where it contains scientific records, specific geological settings or landscapes. This is very meaningful, as an evidence of important geological events, and has special ecological functions that can be utilized for research, education, understanding of geological processes, and conservation. This area includes areas that comply the criteria to become geotourism.
A new MRPC prototype with diamond-like-carbon coated glass electrodes
Authors: Wang X. , Wang K. , Hu D. , Sun Y. , Shang L. , Zhou Y.
Published: March 2021

The Multi-gap Resistive Plate Chamber
(MRPC) has been used in many high energy physics and nuclear
experiments in the last decade, such as ALICE [1] and
STAR [2]. Normally, the MRPC is built with commercial floating
glass (bulk resistivity ρ≈ 1012Ω· cm), which limits the rate
capability to less than 1 kHz/cm2. In modern high energy physics,
with the increase of colliders beam energy and luminosity, the
rate capability of MRPC has to be enhanced accordingly. One normal
way is to decrease the bulk resistivity ρ of the resistive plate,
as the low resistive glass developed by Tsinghua University for
the CBM experiment [3]. Alternatively, the surface of the
electrode is also a possible path for the neutralization of the
avalanche charges. Recently, we managed to carry this method out
by coating a Diamond-Like-Carbon (DLC) layer on the surface of the
floating glass. The DLC layer, realized by the magnetron
sputtering method, has very good physical and chemical
stability. The demanded surface resistivity can be achieved
easily. A series of DLC-coated glasses with different resistivity
has been tested in our lab. We have also made some MRPC prototypes
and tested them with cosmic rays. Some preliminar results,
including the operating current, the efficiency and the time
resolution, have been achieved. More research is ongoing to
improve the design and performance of this new method of
increasing the rate capability of MRPC.
Research on the operation flow of commercial automobile Ro-Ro terminal
Authors: Shen Mengru , Yao Yang , Jiang Shuailiang , Ma Rong , Wei Yongcun
Published: March 2021

This paper studies and designs the specific import operation flow and export operation flow of modern automobile Ro-Ro terminal, and summarizes the loading and unloading operation plan of commercial automobile Ro-Ro terminal. In addition, this paper puts forward the technical points for the safe implementation of the loading and unloading operation of the automobile Ro-Ro wharf from the three links of the loading operation before, during and after the loading operation, which provides reference for the actual operation of the Ro-Ro wharf.
Research on integrated measurement and control device and test technology in smart substation
Authors: Wen Bo , Li Hengxuan , Zhang Kanjun , Li Peng
Published: March 2021

According to the problems of low system integration, no redundant configuration and wide fault influence range of the measurement and control device, this paper research on the scheme of integrated measurement and control device in smart station, which can greatly reduce the number of measurement and control devices and effectively improve the reliability of integrated system. At the same time, the maintenance technology for integrated measurement and control device can improve the efficiency of maintenance for the whole station.
Research on Motion Generation for Machining Involute Tooth Profile Surface Based on Analysis Method
Authors: Huang Zhidong , Li Ying , Yang Cuiying
Published: March 2021

Starting from the configuration characteristics of gear, the pose relationship between grinding wheel and involute tooth profile surface is clarified. Pose matrix of grinding wheel relative to involute tooth profile surface is established, and the necessary motion modules are obtained. A method for designing motion module combination for machining involute tooth profile surface is created, and module combinations are screened. An effective module combination and a reasonable schematic diagram of motion module combination are gived. The method adopted in this paper is beneficial to motion module design for machining involute tooth profile surface.
Evaluation Research on “Anti-Electromagnetic Interference Performance” of Partial Discharge Detection Device in Complicated Strong Electromagnetic Interference Environment
Authors: He Ninghui , Zhou Xiu , Ma Feiyue , Wu Yang , Ma Yunlong , Ni Hui
Published: March 2021

In a strong electromagnetic environment, most of the current anti-interference methods for partial discharge signals of electronic transformers use digital notch filter, which has poor adaptability and stability. This article studies the source of interference and its impact on partial discharge detection, and has accumulated a relatively complete partial discharge sample database. On this basis, a high-performance arbitrary waveform generator is proposed to restore typical partial discharges, and a platform for quantitatively evaluating the anti-electromagnetic interference capability of partial discharge UHF detection devices through interference simulation is established. Experimental results show that the proposed method has high anti-interference performance.
Optimal Device for Waste Heat Recovery Process Based on Convective Drying Technology
Authors: Liao Yusen , Chen Yujiang , Yu Xinyuan
Published: March 2021

With the development of chemical industry, medicine, food and other industrial production in China, the amount of drying to wet materials is increasing, and the energy consumption of drying is also increasing year by year. Among them, the hot and humid waste gas produced by convective drying technology contains a large amount of waste heat, and the recovery and utilization of waste heat through the two-stage combination of gas-gas heat exchange and gas-liquid heat exchange is a method to reduce energy consumption, which has good economic value and energy conservation and emission reduction value.
Design of Experimental Device for Electrical Performance of Mine DC Stabilized Power Supply
Authors: Long Ma
Published: March 2021

In order to improve the testing method of the electrical performance of the mine-used DC stabilized power supply, this paper designed a test device for the electrical performance of the mine-used DC stabilized power supply based on STM32F407VET6 single chip microcomputer. The device is mainly composed of AC power output, DC power input, analog load, operation control and other units. It can achieve AC0∼1254V AC voltage output underground and the output voltage deviation value, source effect, load effect, and overload of the mine DC stabilized power supply. The current protection value and short-circuit current value are tested and displayed on the display of the industrial computer.
Implementation of the Integration of Business and Finance
Authors: Xu Yueming
Published: March 2021

With the continuous transformation and upgrading of the national economy, the market competition environment is becoming more and more fierce. The response method adopted by each enterprise is to promote the integration of industry and finance, and continuously improve the efficiency of the company’s use of resources and its own decision-making level. In order to ensure that the overall management level of the enterprise has been improved to a certain extent. Based on the importance of business-finance integration for enterprises, this paper analyzes the realization of business-finance integration in detail, puts forward some problems that may be encountered in the realization of business-finance integration, and puts forward some solutions based on the lessons learned in the classroom.
Competition and Valuation: A Case Study of Tesla Motors
Authors: Liu Shiyong
Published: March 2021

Tesla’s rapid rise to become one of the world’s most influential automakers has marked the start of a new era in the global automobile industry, where many of the traditional auto companies were overshadowed by Tesla’s dominance. Judging from Politics, Economy, Society and Technology perspectives, Tesla’s market value can potentially be overvalued due to its leading role in the Electrical vehicle market. Economically, Tesla facilities the growth of global economy by creating more employments and manufacturing factories. Socially and politically, Tesla’s Electrical Vehicle reduces the level of negative externalities (e.g., pollution), which aligns with the developmental frameworks proposed by governmental policies and regulations. Meanwhile in technological aspect, Tesla pioneers the innovative design of battery pack to reduce the overall cost of battery and seeks to integrate better automatic driving system into electrical vehicle. Given those merits of Tesla, overoptimism on its stock price is expected. Therefore, it is important for stock traders who are willing to throw money at Tesla to ruminate over their choices before making the investment. In this study, the results of valuation methods indicate that true market value of Tesla has been overestimated due to its irregularly high operating cash flow, price-to-earnings ratio and enterprise value to earnings before interest, taxes, depreciation, and amortization ratio, suggesting its stock price is overvalued.
Spot trading strategy considering multiple constraints for electricity retailers
Authors: Zhou Guang , Jin Yulong , Chen Kang , Zhou ZhiCheng
Published: March 2021

In order to solve the inert trading and irrational trading of electricity retailers in the spot market trading environment, increase the income of electricity retailers and reduce transaction risk, a spot trading strategy considering multiple constraints for electricity retailers is proposed. Similar days are selected by analyzing the date type and the temperature difference of the spot market trading day, on the basis of similar days, the electricity consumption information of electricity retailers’ agent users, day-ahead and real-time electricity price of sport trading market are predicted, combing the user-side excess profit recovery fee, mid-to-long term shortage recovery fee and mid-to-long term curve deviation recovery fee restrictions in Shanxi Province spot trading rules, optimize the mid-to-long term daily 96 points daily electricity purchase curve and day-ahead 96 points daily electricity biding curve, and use the real data of Shanxi spot market transactions to calculate the multi-day income of the electricity retailers to verify the practicability of the spot trading strategies.
Numerical simulation and structure optimization of control rod drop impact in floating reactor
Authors: Luo Qingsong , Xu Huaijin , Guo Yong , Li Hui , Liu Le
Published: March 2021

In order to simulate the impact of control rod assembly on upper grid plate of reactor core after emergency shutdown of offshore floating reactor, the structure size of upper grid plate was optimized. In this study, ADAMS simulation software was used to simulate the impact stress and strain of 50 mm and 100 mm thick upper grid plate with and without spring buffer at 0.5 m / s impact speed. Therefore, the thickness of the buffer plate on the grid can be reduced, and the simulation results show that the buffer plate can be optimized effectively.
Preparation and properties of titanium alloy with binder based on 3DP method
Authors: Xu Yuanyuan , Gu Hai , Li Bin , Zhang Jie , Jiang Jie , Sun Jianhua
Published: March 2021

TC4 material has good comprehensive mechanical properties, but its development is limited due to its complex preparation process and high cost. Three-dimensional printing forming technology has the characteristics of low cost, wide range of materials, fast forming speed, etc. In this paper, the binder and powder formula of 3D printing molding process were studied. According to the viscosity value, surface tension, bonding effect and the service life of nozzle, the optimal formula of binder was selected. Finally, according to the formulation of binder and mixed powder, TC4 blank was prepared by 3d printing machine, TG-DSC curve of PVA and starch was analyzed, degreasing sintering process was designed, degreasing and sintering of TC4 porous material was carried out. Finally, the performance of the parts under different time - aging treatment is studied.
Research and Prospect of Numerical Simulation of River Water Environment
Authors: Li Yan , Luo Yuhu
Published: March 2021

Healthy water environment is the prerequisite for river resource utilization, social and economic development, new urbanization and healthy and happy river construction. Through the literature database retrieval statistics, summarizes the river water environment research to numerical simulation analysis, environmental quality improvement direction. The indicator system, evaluation method and significance of river ecosystem health assessment, and water ecological security assessment are introduced in detail. Finally, the types of river water environment numerical models are summarized, and the advantages and disadvantages of mainstream models and their application conditions and characteristics are compared and analyzed. In order to provide basic reference for river water environment numerical simulation machine watershed ecological environment protection and maintenance.
The Mechanical Properties Analysis of New Rubber Concrete
Authors: Yang Zhen , Wang YongHua , Li MeiHong
Published: March 2021

Rubber cement-based material is a new kind of green material.At present,the research on the influence of rubber on the properties of cement-based materials has obtained some qualitative results (the addition of rubber can reduce the strength and elastic modulus of materials,but can improve the cracking performance of cement-based materials).But the research of the existing rubber mechanism analysis how to affect the performance of cement base material is not clear,as the research object,this article selects the rubber concrete combination of microscopic,mesoscopic and macroscopic,from the mesoscopic level,based on the composite elastic modulus prediction model,at the same time considering the rubber and the effect of pore rubber concrete elastic modulus prediction formula is established;From the macro level,the rubber concrete compressive strength,bending,split strength,modulus of elasticity drying shrinkage and crack resistance test and research,and analyzed the related theory,based on binary complex modulus of elasticity and calculation model,the equations of the elastic modulus of rubber cement mortar prediction formula,explains the difference of the rubber particle size effects on the mechanical properties of cement mortar,the rubber to reduce the mechanical properties of cement mortar in addition because of its “soft” characteristics.
Research on Fuzzy Comprehensive Evaluation of Professional Teaching Standard Setting Effect in Civil Aviation Higher Vocational Colleges Based on Analytic Hierarchy Process
Authors: Zhang Liang , Guan Yangmei
Published: March 2021

In view of the lack of measurement method for the development effect of teaching standards at present, this paper makes a systematic analysis from the perspective of the development of teaching standards, constructs a systematic and perfect evaluation index system, and designs a comprehensive evaluation model for the development effect of teaching standards. The empirical evaluation of the teaching standards of general aviation aviation aviation technology major by using the above-mentioned index system and evaluation method shows that the teaching standards of general aviation aviation technology major have a clear framework, are forward-looking and leading to a certain extent, play an important role in standardizing the construction and teaching guidance of general aviation aviation technology major, and are an important direction and guideline for personnel training in civil aviation higher vocational colleges.
Effect of Different Phosphorus Modifiers on Microstructure and Properties for Al-Si Alloy
Authors: Hong Xiaolu , Chen Dahui , Xu Ying , Zhu Honglei , Zhang Jiang , Liu Yongqiang , Peng Yingjiang , Hou Linchong
Published: March 2021

The coarse primary silicon structure will deteriorate the material properties of Al-Si alloy. It is necessary to optimize the morphology and size of primary silicon through modification, so as to improve the properties of Al-Si alloy. In this paper, four different phosphorus modifiers, AlP4, P-salt, P-Cu and Al-3P, were used to modify the Al-Si alloy. The microstructure and mechanical properties of the modified Al-Si alloy were compared and analyzed.
Analysis of Current Status of Water Pollution in the Yellow River Based on Principal Component
Authors: Liu Chang , Fan Longjiang , Qin Shipeng
Published: March 2021

The Yellow River is the “mother river” of the Chinese nation. The Yellow River is vital to the economic, social development and ecological environment of the surrounding areas. In recent years, with economic development and the acceleration of urbanization, the water environment and water ecology in the Ningxia section of the Yellow River have been polluted to varying degrees. Therefore, it is urgent to investigate the pollution laws of the water environment of the Yellow River and carry out corresponding treatments. First, we extracted six major pollutant indicators from three aspects, and then we conducted a comprehensive evaluation of the water environment of a certain section of the Yellow River in the past 8 months: The entropy method is used to determine the weight of various pollutants’ impact on the water environment, and the comprehensive evaluation index Q of water quality is obtained. Then the Q value of 8 months is compared with the actual data, and then the expected water environment (Type III water) Define the water environment comprehensive evaluation standard index Q_s, combine Q and Q_s to define the degree coefficient h reflecting the degree of water environment quality, and then divide the degree coefficient into intervals according to the principle of equal division, as the index of water environment classification. Finally calculated h=0.0088, according to the water quality grading index, it is concluded that the comprehensive water quality of a certain section of the Yellow River in the past 8 months has been classified as “poor”, and it belongs to the very poor level in the “poor” category.
Research Progress on Toughening and Strengthening Mechanism of Ternary Boride Base Cermets
Authors: Zhang Xue , Du Jin , Su Guosheng , Zhou Tingting , Zhang Chongyan , Kong Xiangmin
Published: March 2021

Cermets cover a wide range of applications in many related industries, such as aerospace key parts, automotive, mold, etc., and are often used to prepare various wear-resistant and corrosion-resistant roller tables, liners, molds and tools, etc. . Ternary boride-based cermet materials are considered to be the most promising class of cermet materials because of their advantages such as high melting point, high hardness, high wear resistance and high oxidation resistance. However, ternary boride-based cermets exhibits some defects of large brittleness and low toughness. This article summarizes the latest research progress on ternary boride based cermets, and mainly discusses the influence of mechanical properties of ternary boride based cermets and the application of ternary boride based cermets by reinforcements and alloy elements. The current situation and the research direction of ternary boride based cermets are prospected.
Air Quality Index Prediction Based on Improved PSO-BP
Authors: Sun Xiali , Li Shixin , Chen Xi , Wang Kun
Published: March 2021

For air quality index prediction problem, this paper puts forward the optimization based on improved PSO - BP algorithm, the method using particle swarm weights and threshold of BP neural network is optimized, and the update each particle’s position and speed of the weight of adaptive adjustment strategy, to balance the global optimization and local optimization ability, and it has been verified by experiment that the improved PSO - BP neural network model is compared with PSO -BP and GA - BP and BP on prediction accuracy improved.
Study on performance change of phenolic resin impregnated graphite in acid environment
Authors: Chen Yi , Dong Liang , Liu Chongyang , Xu Jinsha , Yang Zhenguo
Published: March 2021

Phenolic impregnated graphite is a new kind of material with higher corrosion resistance and thermal conductivity. In the chemical industry, it is often used to make containers and pipes containing strong acid and alkali medium. In this paper, the working conditions of impregnated graphite materials in the actual production were simulated in the laboratory, and the. mechanical properties and material characterization of impregnated graphite after soaking in sulfuric acid at different temperatures were compared. The results show that the tensile strength of phenolic resin impregnated graphite decreases with the increase of immersion temperature under the action of acid medium and temperature; the results of thermogravimetric analysis show that the inner phenolic resin expands and extrudes graphite particles to produce internal stress, and the graphite particles will fall off partially, but the chemical structure of phenolic resin does not change.
Transparent SiOxCyHz Barrier Film Prepared by PECVD with Upper and Lower Pair Electrode Rolls Structure
Authors: Dong Maojin , Wang Xiaojun , Feng Yudong , He Dan , Qin Lili , Wang Yi
Published: March 2021

Flexible and transparent barrier film is demanded in the fields of organic solar thin-film cells, flexible organic light-emitting diodes, electronic paper and vacuum insulation boards. To prepare films with high water resistance, flexible SiOxCyHz films were prepared on PET using HMDSO as monomer and Oxygen (O2) as reaction gas. SiOxCyHz films were prepared by plasma enhanced chemical vapor deposition (PECVD) with upper and lower pair electrode rolls structure, with the width of electrode rolls up to 600 mm. The influences of oxygen content, film thickness, oxygen/monomer ratio, reaction vacuum degree on water vapor transmission rate (WVTR) were studied. This coating method of oxide high barrier film has great application potential in the development of barrier film industry.
Development of Automatic Control System for Cutting Fluid Filtration
Authors: Hu Kai , Phonepasith Manivone
Published: March 2021

Cutting fluid by which the cutting tools and workpieces can be cooled and lubricated play an important role. The filtration and recycling for cutting fluid will effectively remove the iron filings, dust and impurities from the cutting fluid, reduce the secondary pollution to the processing site in the process of recycling, and improve the result of cutting fluid recycling. The paper provides a kind of the design of automatic filtering control system for cutting fluid, the system can recycle and filter the cutting fluid which has been used in the process of production, and recycle again, so as to save energy greatly, protect the environment and increase economic benefits. meanwhile the whole recycling and filtering process can be controlled automatically or manually on the touch screen, and the status of each working part of the system can be displayed in real time, and the judgment algorithm for filter belt replacement has been optimized, so as to improve the operating efficiency of the system further, enhance the convenience, stability and reliability.
The effect of recycled WPC on the performance of composite materials
Authors: Luo Tong , Cheng Shangwei
Published: March 2021

In order to improve the comprehensive utilization of waste Wood-Plastic Composites(WPC), high-density polyethylene(PE)and polypropylene(PP) WPC composites filled with recycled WPC were prepared. The effects of different recycled WPC content on the processing performance, mechanical properties and artificial accelerated aging performance of composite materials were studied. The results show that when the quality fraction of recycled WPC is less than 20%, it has little influence on the properties of composite materials. With the increase of the quality fraction of recycled WPC by more than 20%, all the processability, mechanical properties and artificial accelerated aging property of composite materials show a significant decline.
Research and application of gas drainage technology by downward drilling holes
Authors: Qin Muguang
Published: March 2021

Aiming at the undesirable phenomenon of low drainage concentration and poor effect in the downward boreholes in Panjiang mining area, the gas drainage technology of “full casing, two plugs and one injection, sealed hole under pressure” and pressurized air and water was proposed. And the on-site implementation was carried out in 21126 transportation jacking lanes of Tucheng mine. The research results show that the pressurized air blowing water technology effectively solves the problems of down-drilling slag and water accumulation, improves the gas drainage effect of the down-draining drilling, effectively solves the problem of regional outburst prevention, improves the efficiency of excavation, and promotes the safety of mine production.
Evaluation of Local Scour Calculation Equations for Bridge Piers in Sandy Riverbed
Authors: Cao Jin , Chen Juxiang , Zhu Dayong , Wei Song
Published: March 2021

Local scour depth is the key index of foundation design of bridge across river. At present, there are many equations to calculate the scour depth of bridge piers, but the results of different equations vary greatly. It is still a difficult problem for bridge designers how to choose the appropriate equation for calculating local scour depth. Six typical equations for calculating local scour depth were selected to compare and analyze the influences of pier width, velocity, water depth in front of piers and bed sand particle size on the local scour depth. The results showed that bed sand particle size and geometric non-uniformity coefficient had the most significant influence on the scour depth. It was proposed that the prediction equation should be selected according to the size range and uniformity of bed sand.
Effect of Mechanochemical Activation on Peat Humic Acid
Authors: Ge Lei , Yang Chenxi , Wang Jian
Published: March 2021

Mechanochemical method is an efficient processing method that uses mechanical means to change the structure and physical and chemical properties of objects. This article takes peat from Erlintu Town, Yuyang District, Yulin City, Shaanxi Province as an example. It is activated by mechanochemical method, and then humic acid and fulvic acid are extracted by alkali-soluble acid purification technology. The results show that mechanochemical the method can improve the extraction rate of humic acid and fulvic acid in peat. Among them, the mechanochemical method with percarbonamide as the oxidant and sodium hexametaphosphate as the grinding aid has the best effect of activating peat. Mechanochemical methods can increase the molecular condensation degree and molecular relative mass of humic acid, but reduce the molecular condensation degree and molecular relative mass of fulvic acid.
Research on the current situation and Development Countermeasures of Wenzhou digital agriculture
Authors: Tang Wenjie , Lin Chanjuan , Cui Xiaojun
Published: March 2021

Research on the current situation and Development Countermeasures of digital agriculture in Wenzhou the development level of county digital agriculture in Zhejiang province leads the whole country. As one of the important cities in Zhejiang Province, the development level of digital agriculture in Wenzhou does not match its status. This paper analyzes the current situation of digital agriculture in Wenzhou, and thinks that the digital agriculture in Wenzhou is relatively weak and unbalanced. It is necessary to further consolidate the foundation of digital transformation in Wenzhou agriculture and rural areas, comprehensively improve the digital level of Wenzhou agriculture industry chain, actively explore the new mode of Wenzhou digital agriculture integration, and build a digital skills popularization system for rural areas
The mechanism underlying grazing shaping stoichiometry of plant community on a grassland of Guizhou subtropical plateau
Authors: Ding Leilei , Zhang Yujun , Liu Jiajia , Zhang Wen , Wang Zhiwei , Ruan Xirui , Shu Jianhong , Wang Puchang , Liu Xiufeng
Published: March 2021

Livestock grazing is a traditional and major use of grassland in China subtropics. However, plant stoichiometry and how it was affected by grazing in these ecosystems have been poorly explored. Here, the responses in plant nutrition and stoichiometry as well as soil nutrition and stoichiometry under representative grazing intensities (i.e., moderate grazing and heavy grazing) compared with no-grazing were characterized, the drivers of plant stoichiometry were explored in a subtropical artificial grassland, SW China. Wilcoxon test showed that grazing intensity significantly changed the response of soil OC, TN, AN, AP, AK, pH, OC: TN, AN: AP, AN: AK, AP: AK, and AP: AK. Grazing intensity changed the response in N, ASH, EE, ADF, P, N: P, N: P, N: Ca and P: Ca of plant. Path analysis showed the effect of grazing intensity on the stoichiometric ratio of nitrogen and phosphorus in plant community was achieved through the removal of herbivores. Our research provides some mechanistic understanding of grazing management of subtropical grassland, and also provides new insights and useful reference for the protection and utilization of grassland in Guizhou Plateau.
Performance analysis and optimized design of a certain frame
Authors: Deng Shiping
Published: March 2021

In recent years, energy shortages and environmental pollution have become increasingly prominent, and automobile lightweight has become an important field in the development of the automobile industry. This paper analyses the frame performance of an all-terrain single-seat off-road vehicle and optimizes the structure design. The weight of the new structure has been reduced by 4.084 kg, and the weight reduction rate has reached 12.83%. The statics analysis and modal analysis of the new frame structure show that the new structure still meets the requirements of usage.
Fractal characteristics of soil particle size in loess hilly areas with different years of conversion
Authors: Meng Tingting , Jin Minghui , Cheng Jie
Published: March 2021

The purpose of this study was to investigate the change of soil particle composition and its effect on the fractal dimension of grassland under different years of conversion. The changes of soil particle composition and soil fractal dimension were analyzed by taking the 8-year grassland and 31-year grassland in the Yuanzegou watershed of the loess hilly region as the research objects, and taking the sloping farmland as the control. The results showed that the clay content of soil was increased by 69.6%, 47.6% and 8.80%, 8.7%, respectively, in the 31-year grassland and the 8-year grassland in the 0-20cm, 20-40cm. The decrease of sand content was 38.7%, 18.2% and 15.6%, and 13.5%, respectively, which were significantly different from that of the 31-years grassland (P<0.05). The contents of particles in the 40∼60cm soil layer did not change significantly. fractal dimension range from 2.6 to 2.7, the expression for the conversion of 31 years grassland>grassland>changing slope farmland 8 years, the fractal dimension of soil particles increased along with the increasing length of the grass farmland, in 0∼20, 20∼40cm soil layer, the conversion of 31 years grassland soil particles fractal dimension D and slope have significant difference (P<0.05). The fractal dimension of soil particle volume was positively correlated with soil clay (P<0.01), and positively correlated with soil particle size on farmland and grassland after 31 years of conversion (R2=0.6970, 0.6701), but not on grassland after 8 years of conversion. There was a negative correlation between soil sand content and fractal dimension of soil particles in the three plots, but there was only a significant difference in slope farmland.
Study on EOR method in high water cut stage of low permeability A Oilfield
Authors: Shi Yuhui
Published: March 2021

By using coring, logging, testing data and dynamic data of oil and water wells, the geological recognition, drive system evaluation and remaining oil research after infilling adjustment of different well patterns are carried out, the dominant channel of water drive and the existing position of remaining oil in different well pattern periods. It can be used for reference to improve development effect and oil recovery of other low permeability oilfields in high water cut stage A Oilfield is a typical low-permeability oilfield, which has the characteristics of poor physical properties, start-up fracture gradient and natural fracture development. After more than 30 years of waterflooding development, the oilfield has achieved good development results through multiple rounds of comprehensive adjustment of water injection wells and oil well measures. But at present, the oil field has entered the high water cut stage, the remaining oil is more scattered, the effect of adjustment means is poor, and the oil recovery rate is reduced, so it is necessary to explore the technical methods to improve the development effect and further enhance the oil recovery. In this paper, the recovery of oil field is evaluated by using the results of indoor core, empirical formula method and reservoir engineering method, and the potential of readjustment of oil field is clarified. Secondly, the reservoir geological recognition and multi-disciplinary remaining oil recognition are carried out, the dominant channel of water drive is identified, the type, existing position and formation reason of remaining oil are clarified, and the comprehensive treatment countermeasures based on the corresponding adjustment and plugging at both ends of oil and water wells are put forward; the application means of periodic water injection is developed, and the cooperation with deep water adjustment and flooding is explored, so as to further expand the affected volume, Methods of EOR. The typical application well area effect has been obviously improved, which provides reference for other low permeability oil fields to improve development effect and enhance oil recovery.
Organic reconstruction and application of soils
Authors: Lei Na , Zhang Yang , He Jing , Dong Qiguang
Published: March 2021

The organic reconstruction of soil generally means that human beings adopt engineering methods to give full play to their subjective initiative under the premise of respecting the laws of nature, so that the process of soil formation is accelerated, slowed down or reversed, and the organic process is driven by inorganic means or promoted by organic development. In actual operation, the soil can be reconstructed by using physical, chemical and biological reconstruction methods through technical means such as replacement, compounding, addition and reduction. The soil construction can increase the area of arable land, relieve the shortage of land in our country, and at the same time improve soil quality, ensure regional food security, build a new ecosystem, and ensure regional sustainable development.
A Prediction-Based Truck Scheduling Method for Open-Pit Mines and Its Numerical Study
Authors: Tian Fengliang , Sun XiaoYu , Gu XiaoWei , Chen Yu
Published: March 2021

In this paper, we proposed a two-stage approach to use real-time prediction for truck scheduling in open-pit mines. We studied the truck scheduling problem using two economic concepts: risk and utility. To schedule trucks by computer, a recursive formula of the truck loading time has been established in this paper. The utility is used to measure the benefit that may be gained by using a particular scheduling strategy. The risk is used to measure the difficulty for a truck to be loaded in time. Inspired by Occam’s razor, we noted the relationship between the risk and the number of factors considered in the algorithm. On this basis, how to reduce the risk of scheduling when the prediction is inaccurate is studied. To verify these methods, we performed simulation experiments based on real data. The experimental results show that our approach can balance the efficiency of trucks and shovels. The impact of the inaccurate prediction on the output can be reduced by risk reduction.
Research on the Path of Cultural Integration of Landless Farmers in Weifang City Based on New Urbanization
Authors: Yu Yuan
Published: March 2021

Based on the current situation that culture integration is difficult in the social integration of land-losing farmers, focusing on the improvement of culture, literacy and knowledge and skills of land-losing farmers, aiming at the problems such as the imbalance between cognitive level and modern development level, the great difference between urban and rural lifestyles, and the disconnection between knowledge and skills and the employment market demand, this paper takes the cultural adaptation in the city and the creative transformation and inheritance of rural culture as the foothold, deeply analyzes the cultural root of the cultural integration dilemma, and tries to provide a feasible path to solve the exploration and research on the cultural integration of land-losing farmers in Weifang based on new urbanization.
Exploration on Reform of Materials Forming and Control Engineering for Intelligent and Additive Manufacturing
Authors: Chen Zezhong
Published: March 2021

With the development of new technologies such as intelligent manufacturing and additive manufacturing, it is necessary to reform and upgrade traditional major of materials forming and control engineering. In 2019, the major of materials forming and control engineering in University of Shanghai for Science and Technology successfully passed China engineering education certification. In order to meet the requirements of continuous improvement, new courses on intelligent manufacturing and additive manufacturing are added into the new training program of the major, and new major orientations are designed in the curriculum system, which can better fit the training demand of excellent talents from advanced manufacturing industries of Shanghai and Yangtze River Delta.
Analysis of Iterative Deepening A* Algorithm
Authors: Jiang Wenrong
Published: March 2021

The A* algorithm is a direct search method. It can effectively solve the shortest path problem in static routing networks. It is also an effective method to deal with a large number of search problems. The closer the artificially estimated distance value in the algorithm is to the actual value, the faster the final search speed will be. This article focuses on the heuristic A* algorithm and discusses the problem of out-of-order Rubik’s Cube searching the shortest feasible solution. It discusses the implementation ideas, advantages and disadvantages, and practical application value of the A*(IDA*) algorithm based on iterative deepening. The development of heuristic algorithms presents some personal insights.
A Fuzzy Comprehensive Evaluation Approach for the 3D Modeling Accuracy of UAV Oblique Photogrammetry
Authors: Zhang Zhaohu , Zhang Yongzhi , Yong Zhaojun , Liang Jinzheng , Ye Xinyang , Zhang Qiuwen
Published: March 2021

3D modeling is the important foundation of virtual reality and scene simulation. The technology of UAV oblique photogrammetry provides a new way for 3D modeling, and the accuracy becomes the key of its application. Since there are a lot of uncertainties in 3D modeling of UAV oblique photogrammetry, this paper proposed a fuzzy comprehensive evaluation approach to deal with this uncertain problem. Firstly, according to the composition of 3D modeling system based on UAV oblique photogrammetry, the main impact factors of 3D modeling accuracy are determined, and the indicator system of accuracy evaluation is therefore constructed. Secondly, by using the method of analytic hierarchy process, the weights and membership degrees of each indicator are calculated. Finally, the proposed approach is applied and validated in the case study. After the fuzzy mapping by the dot multiplication performance between the indicator weights and membership degrees, the comprehensive evaluation sets of different cases are obtained, and their corresponding 3D modeling accuracies can be determined based on the maximum membership degree principle. It is concluded that the fuzzy comprehensive evaluation approach proposed in this paper can quickly and correctly assess the 3D modeling accuracy of UAV oblique photogrammetry.
Analysis of Maximum and Minimum Temperature in Qilian Mountainous, Northwest China
Authors: Zhao Chuancheng , Gao Hongkai , Yao Shuxia , Zhou Jiaxin
Published: March 2021

As one of the key elements of climate change, the temperature changes can affects the energy balance and hydrological cycle. The variations and trend of mean annual maximum temperature (Tmax) and minimum temperature (Tmin) were analyzed by using linear regress for 44 stations inside and surrounding the Qilian Mountains for period of 1960-2017. The results have shown that the variations of mean annual Tmaxand Tminhave significant increasing in whole study regions. The warming trend of mean annual Tmixis higher than that of Tmax. Both the trend of mean annual Tmaxand Tminin the southern slope is warmer than those in the northern slope of Qilian Mountains. In spring, the warming trend of Tmaxis significantly weaker inside than that outside the Qilian Mountains. For all seasons, the trend of Tmaxand Tminis the highest in winter, and is weakest in spring.