bluuebunny/crossref_metadata_2025 huggingface dataset:
Laser Resonant Photoacoustic Spectrometer for Methane Detection
Authors: Yun Yuxin , Zhao Xiaoxiao
Published: July 2020

A laser resonant photoacoustic (PA) spectrometer has been designed for methane detection. The design ideas and methods of the device are discussed in detail. Relevant tests are designed and done for testing and verifying the important parameters of the device. The experimental results show that the radiation wavelength of the distributed feedback (DFB) diode laser increases approximately linearly with the increase of operating temperature or injection current, and the change gradient of radiation wavelength to operating temperature is greater than that to injection current. Under the condition of low gas concentration and low laser power, the relationship between PA signal, laser power and methane concentration is linear.
A New Method for Measuring the Complex Permittivity and Permeability of Sintered Material FeSiAl Used for Microwave-Absorbing Load
Authors: Zhang Fang , Shen Lianguan , Pei Yuanji
Published: July 2020

This paper describes a new method for measuring the complex permittivity and permeability of a sintered microwave-absorbing material. Thorough knowledge about microwave-absorbing materials is very important for the design and construction of accelerators. Although many methods of measuring the permittivity and permeability of a material have been developed and tested successfully, they are not suited to cases in which the microwave-absorbing material is coated on an oxygen-free high-conductivity copper (OFHC) surface by means of a special sintering technology. Thus, a new method is developed through a combination of testing and simulations. The complex permittivity and permeability of the microwave-absorbing material FeSiAl was obtained by this means, and a collinear load was designed based on the measurement results. The linear accelerator (LINAC) with the collinear load has been running well.
Review of Polymer Self-lubricating Coatings
Authors: Feng Qing , Zou Shuai , Li Haoming , Dou Mingyuan , Huang Fuchuan
Published: July 2020

In recent years, polymer self-lubricating coatings have become a research hotspot of composite materials and tribology workers because of the characteristics of matrix polymer and solid lubricant. Based on a large amount of literature at home and abroad, the characteristics, structural design and preparation technology of polymer self-lubricating coatings are reviewed, and the research trend of polymer self-lubricating coatings is prospected.
Research on Anti-cavitation Coating Performance of Shipping Fluid Machinery
Authors: Hu Yiming , Wang yuansheng , Ding Zhangxiong , Wu Jie , Hou yingzhe , Wu hao , Zhou Longyu , Zhu haojiang , Gao Haitao
Published: July 2020

In this paper, micro-nano-structure and nano-structure WC-based coatings were prepared by supersonic flame spraying technology for the cavitation of fluid mechanical parts. We used SEM and XRD to analyze the coating structure, mechanical properties and electrochemical properties. We also studied the cavitation’s mechanism of the coating in 3.5% NaCl simulated seawater medium. The results show that the micro-nano structure WC-10Cr-4Cr coating prepared by supersonic flame spraying has a micro-nano structure and added 4% Cr element, while the nanostructure WC-12Co coating is prone to have decarburization during the preparation process, resulting in generating a certain amount of W to reduce the hardness of the coating. Therefore, the micro-nano structure WC-10Cr-4Cr coating has better porosity, micro hardness and crack toughness properties. In the simulated seawater cavitation environment, the coating has more excellent anti-cavitation performance.
Application research of steel fiber rubber regenerated concrete engineering
Authors: Chen Yanyan , Liang Xiaoguang , Liang Lijun
Published: July 2020

With the booming development of China’s building industry, the recycling of building materials can achieve the effect of reducing energy consumption. For the construction and development of rural areas, rural roads and small water conservancy projects are also being gradually optimized and transformed, in which a lot of waste building materials will be generated. With the progress of science and technology and the in-depth research on regenerated concrete, the regenerated concrete began to be promoted everywhere. This paper elaborates the performance of the new steel fiber regenerated concrete rubber, considered from the aspects of reducing engineering cost and shortening the construction period, discusses application of regenerated concrete to rural road construction, small water drains and other projects, so as to provide a reference for the use of renewable resources in rural areas, and promoting the development of more scientific and ecological construction industry.
Effect of CO2/N2 on explosion vent behavior of lycopodium/air mixtures in a 20-L sphere
Authors: Hou Yujie , Yu Jianliang , Jiang Zixu , Yan Xingqing , Ji Wen tao , Yu Xiaozhe , Lv Xianshu
Published: July 2020

To investigate the inerting effect of CO2/N2 on the explosion venting behaviors of lycopodium/air, a standard 20 L spherical chamber, with a thermo-gravimetric analyzer TGA Q500 was adopted to determine the explosion severity and mechanism of inhibition. In the heat flow of the N2 atmosphere and CO2 atmosphere, the pyrolysis processes of lycopodium powder show obvious differences from 370°C approximately. Through the whole explosion process, CO2 plays a key role and it can effectively cut off the contact between dust and oxygen. The particles with free radicals decomposed from heat lycopodium powder such as nitrogen and carbon will react lowly under the blocking effect of CO2. Meanwhile, carbon, nitrogen and other atoms can participate in chain reaction and react with active groups, which greatly reduces the risk of powder explosion. The explosion pressure Pex
and the maximum reduced pressure Pred
were obtained with lycopodium powder explosion under a wide range of CO2 concentrations. Compared with the pure physical suppression principle of N2 in the explosion process, CO2 can participate in the explosive reaction more effectively, and hence has a better suppression effect of the explosion than N2. An unexpected behavior has been found in relation to the explosion venting behavior. Under the smaller vent diameter or at higher static activation overpressures, the suppressive effects of carbon dioxide to lycopodium/air venting explosion are better than those of nitrogen.
Algorithm of applying the energy conservation law to study the thermal stress-strain state of a rod of variable cross section with the simultaneous presence of local temperatures, heat exchanges and thermal insulations
Authors: Muheyat Niyazbek , Kuenssaule Talp , Kudaykulov A.K , Mukaddas arshidinova , Anarbay kuaykulovi , Azat tashev
Published: July 2020

The bearing elements of power plants, internal combustion engines of jet engines, nuclear thermal power plants, gas-generating power plants, processing lines, and spacecraft antennas are rods of variable cross-section. They work in a difficult temperature environment. In this paper, we propose an algorithm for applying the fundamental law of energy conservation for a deep study of the resulting thermal-stress-strain state of a rod of limited length and variable cross-section in the simultaneous presence of local temperatures, heat exchange and thermal insulation. At the same time, the obtained solutions in the form of determining the temperature field, displacement, all the components of deformations and stresses, as well as the calculated values of the rod elongation and the resulting axial force are highly accurate at the level of satisfying the energy conservation law.
Interpolating Equation of Precision Platinum Resistance Thermometers in the Temperature Range between -80°C and 300 °C
Authors: Jiang Yingying , Zhu Yichen , Zhou Bingyan , Yao Liyao
Published: July 2020

This paper compares two interpolation equations for the calibration of precision platinum resistance thermometers (PPRTs) in the temperature range between -80°C and 300°C. They are the deviation function specified in the International Temperature Scale of 1990 (ITS-90), and the quadratic Callendar–van Dusen (CVD) equation. It was found that when the calibration range was between -80°C and 300 °C, ITS-90 deviation function resulted in a measurement error-of-fit of ±23mK, and the CVD equation resulted in ±24mK. In the temperature range of (-80∼0)°C, ITS-90 deviation function showed distinctly better performance than the CVD equation. When the temperature range was between 0°C and 100°C, the difference among the two equations was insignificant. In the temperature range of (100∼300)°C, the measurement error-of-fit of ITS-90 deviation function increased with temperature, and the maximum error-of fit under the CVD equation appeared at 200°C. If the temperature range is wider, the ITS-90 deviation function had better calibration effect. While the CVD equation worked better in a narrow temperature range.
Analysis and Research of a DC24V Surge Suppression Circuit
Authors: Zhong JianFu , Yu ChangHong , Liu MengLi , Cen SongQing
Published: July 2020

In the industrial environment, the stability and safety of the electronic equipment are determined by the anti-interference degree of electromagnetic compatibility. In this paper, a DC24V surge suppression circuit which can be used in embedded data collector is studied theoretically and experimentally. The feasibility of the circuit is verified by the circuit simulation, and then the surge experiment is carried out according to the circuit design board. At the end of the paper, we make a summary based on the experimental data to verify the practicability and feasibility of the circuit.
Intelligent substation fault diagnosis based on optimization support vector machine
Authors: Chen Bin , Liu Guangzhen , Mu Zongjun , Xu Huibo , Tian Zhao , She Wei , Liu Wei
Published: July 2020

In view of the present intelligent substation fault diagnosis of complicated structure, sample data acquisition difficult, randomness of failure and other issues, build a kind of intelligent substation fault diagnosis based on the optimization of support vector machine (SVM) model, first of all, through the principal component analysis (pca) to simplify the fault source and key fault feature extraction, reduce the complexity of fault diagnosis.Then, based on the characteristics of the operation mode of the substation, the multi-classification SVM classifier is constructed and optimized by the imperial competition algorithm to find the optimal parameters. At last, the fault events of real substation are verified by experiments. The results show that the proposed fault diagnosis method can effectively solve the problem of less training samples and has a better diagnosis effect.
An Analysis of a shutdown caused by a misoperation of differential protection of high-voltage auxiliary transformer
Authors: Qian Zhunli
Published: July 2020

In response to an accident of misoperation of the high-voltage factory transformer differential protection, the cause of the misoperation was investigated and analyzed from the perspective of the volt-ampere characteristics of the current transformer and the protection operation information, and it pointed out the abnormal interruption of DSP memory caused by the malfunction of differential protection, and put forward the corresponding treatment and preventive measures.
Technology Progress and Energy Efficiency: An Empirical Analysis of Shanghai Industrial Firms
Authors: Wang Chen , Fan Ying , Sun Kege
Published: July 2020

In the tough stage of transition development, it is necessary for Shanghai industrial sector to take measures like R&D and technology import to improve energy efficiency, which also contributes to carbon emission reduction, reduction of the external dependence of energy consumption and the achievement of green development. This paper estimates energy efficiency of Shanghai industrial sector based on historical data of industrial enterprises in Shanghai and analyzes the mechanism and level of the influence of factors like R&D and technology import on energy efficiency of the industrial enterprises. The results show that the internal R&D investment of enterprises have a significant positive impact on energy efficiency of collective and private enterprises in Shanghai. Foreign investment has positive spill-over effect and leads to energy efficiency improvement for foreign-invested enterprises in Shanghai. Besides, the deeper the enterprises engage in export trade, the higher the energy intensity and the lower the energy efficiency will be, which implies that the export-oriented enterprises are more likely to produce and export energy-intensive products and suffer from energy efficiency loss. So, it is not only necessary to encourage internal R&D innovation of enterprises, but also important to implement transformation and upgrading of enterprises in the value chain of international trade.
Mechanism Design for Participation of Demand Response in China Power Market
Authors: Zhang Gao , Xue Song , Zhang Xiaoxuan
Published: July 2020

At present, with the rapid development of demand response in China, various market players such as electric vehicles, energy storage, virtual power plants, and load aggregators are constantly enriched. However, due to the imperfect market-oriented trading mechanism, the potential and enthusiasm of demand response have not been fully released. With the accelerated construction of China’s power market, various trading mechanisms such as spot market and ancillary services market have gradually improved. Based on the development of China’s power market, this paper designs a market-based transaction mechanism for demand response, and proposes a future development path for demand response. In the end, the subsidy for demand response development in China is estimated, which supports the market-oriented participation path of demand response in China’s power market.
Time-delay compensation and weighted feedforward control for reducing current harmonic of grid-connected inverter in weak power network
Authors: Gao Haitao , Wan Huaqing , Cui Qiguan , Liu Yiwen
Published: July 2020

In order to improve the quality of grid-connected current, the full feed forward control of grid voltage is often used to increase the output impedance of inverter. However, due to the influence of digital control delay, not only the harmonic suppression effect is weakened, but also the negative phase shift of the output impedance, which deteriorates the stability of the inverter in the weak network. In this paper, a time-delay compensation and weighted feedforward control strategy is proposed, in which a series of quasi-resonant items are added to the full feed forward circuit, and only the feedforward background harmonics appear at the frequency. By designing the quasi-resonant term, not only the phase delay introduced by the digital control can be compensated, but also the higher output impedance at the background harmonic frequency can be obtained, and the negative phase shift of output impedance can be reduced, and to improve the stability of the inverter in a weak power grid. Finally, a 6kw inverter prototype is built, and the validity and correctness of the proposed control strategy are verified by experiments.
Corrosion Risks Assessment Management of Natural Gas Pipelines Based on TPI Management Mode
Authors: Zhang Long , Zhou Yisu , Zhou Lei , Wang Weiwei , An Chen
Published: July 2020

In order to clarify the goals of corrosion management of natural gas pipelines, achieve key, orderly, visual and dynamic management of indicators at all levels and get rid of trivial management, the TPI management was used to manage the corrosion block index of natural gas pipelines. Firstly, clarify the management objectives of the corrosion block of natural gas pipelines, and achieve the activity decomposition of the management objectives. Secondly, through the independent-coupling analysis of the risk and the Gray evaluation theory, it proposes the Gray consequence grade equation and the Gray risk matrix, which determines the TPI indicators, and develops an economic rating system. The results of the study indicate that the pipeline is in a critical stage and require the implementation of the targeted management. In addition, the risk value of the outer wall corrosion is the highest in the target activity, and the TPI indicators of the entire TPI system of the Nature Gas pipelines corrosion are as follows: the integrity of the outer protective layer, outer coating thickness, soil pH, soil salinity, soil sulphur, residual stress, sudden stress, design stress, SCC sensitivity, material mechanical strength, material corrosion resistance, inner coating thickness, protection potential, pigging quality, H2S content and CO2 content. And it establishes an economic evaluation model according to the TPI system.
Real-road Emission and Fuel Economy of Buses using Different Fuel
Authors: Wang Fengbin , Yu Quanshun , Wang Xuefeng , Ma Juyu
Published: July 2020

The real-road emission and the fuel economy of 2 China-VI buses and 2 China-III buses using different fuel are tested using portable emission measurement system. The results show that, compared with Beijing VI diesel buses, China VI buses using B5 biodiesel is 33.1% lower in CO specific emission, 15.6% higher in NOx specific emission, and 13.1% lower in PN specific emission. The CO emission factors of the four buses using B5 biodiesel decrease by 29.5% averagely compared with Beijing VI diesel buses, while the NOx emission factors increase by 12.7% and PN emission factors decrease by 9.1%; the CO2 emission factors increase by 11.3% and thus the fuel consumption per 100km increase by 11.51% which is calculated using carbon-balance method considering the impact by fuel density. The fuel economy difference is high. More research on the impact on fuel economy by fuel heat value or other physical and chemical parameters is necessary in the future.
The Reliability Research and Risk Analysis of Spent Fuel Pool under Internal Fire
Authors: Xu Zhixin , Wang Ming , Hou WenYu
Published: July 2020

The Fukushima nuclear disaster has raised the focus on the reliability and risk evaluation of the spent fuel pool (SFP), especially the fire risk. From a safety point of view, the low decay heat of the spent fuel assemblies and large water inventory may make the accident progress very slow, but a large number of fuel assemblies stored inside the pool and without containment above the SFP building might bring greater risk. For pressurized water reactor HPR1000 nuclear power plant, the reliability and risk of spent fuel pool under internal fire is assessed. The fire probabilistic safety analysis method is used to assess the reliability and risk of spent fuel pool under internal fire. Through quantitative analysis, we can know more about which aspects play a leading role in the internal fire risk contribution.
Multi-objective Lightweight Design of Bracket Based on Sensitivity Analysis
Authors: Guo Zhounan , Wang Bingzhe , Zhao Fei
Published: July 2020

This paper takes a bracket as the research object. In order to realize the lightweight design on the basis of ensuring its static characteristics, use the sensitivity analysis method to analyze the magnitude of the impact of key dimensions on the design of the bracket structure; Combined with the multi-objective optimization design method, the lightest mass, maximum deformation and maximum stress as the optimization objectives, to obtain a set of optimal size values. Finite element analysis of the static characteristics of the structure before and after optimization. After optimization, the weight of the bracket decreased by 2.35%, and the performance was also improved. The results show that combining sensitivity analysis and multi-objective optimization is an effective way to design lightweight structures.
Comparison and Application of Neural Networks in LWD Lithology Identification
Authors: Chen Gang , Chen Long , Li Quanxin
Published: July 2020

Aiming at the problems of poor fault tolerance, low automation and low interpretation accuracy of traditional lithology identification methods, through the application of neural network autonomous learning prediction analysis methods, different neural network prediction methods were compared to select a more suitable field practical method for the logging-while-drilling (LWD) system. It has been found that, with the same prediction method and the same logging curve, the more training samples obtained in the standard interval, the higher the accuracy. The result is obtained through comparison: the PNN probabilistic neural network method has better effect in production application, high recognition accuracy, and the shortest training recognition time. It can still maintain a high recognition level when acquiring fewer logging data information.
Research on Gaussian Plume Model of Gas Diffusion in Coal Mine Roadway Based on BP Neural Network Optimized by Genetic Algorithm
Authors: Nie Zhen , Ma Hongwei , Zhang Yishu
Published: July 2020

Intelligent monitoring and control of harmful gas in a coal mine is an important aspect of the building on intelligent and green mine. It is a hot spot of artificial intelligence research in the coal mine to study the new technology of dynamic prediction of harmful gas by using artificial intelligence, big data and other interdisciplinary fusion methods, and gradually replace the artificial monitoring work. By researching the gas diffusion theory and the characteristics of the coal mine environment, this paper uses the Gaussian plume model to simulate the gas diffusion law of coal mine roadway, and puts forward a gas prediction model optimized by genetic algorithm and BP neural network. The algorithm takes the absolute error between the predicted output of gas source term and the field measured value as the peculiar fitness value and optimizes it. The results show that the optimized BP neural network can obtain the best concentration prediction value for short time and a small error. Compared with the traditional gas prediction method in coal mine, this method has the advantages of small calculation amount and high prediction accuracy, and it can improve the reliability of the model by continuous machine learning combined with daily monitoring, which provides a new technical solution for the intelligent detection of environmental information in coal mine roadway.
Research and Application of Cleaning and Coating for Condenser
Authors: He Fengyuan , Niu Ruqing , Wang Fei , Li Yao , Liu Chengming
Published: July 2020

The scale on the water side of condenser copper pipe of unit 3 in a power plant has exceeded 1mm and “dezincification corrosion” has occurred. The condenser copper tubes were cleaned and coated by static and dynamic tests. After the completion of the project, the inner wall of the copper pipe is cleaned and the coating is in good condition, achieving the expected effect.
Application of GIS and BIM Integration Technology in Construction Management
Authors: Han Zhong Hua , Wang Zhen Kai , Gao Chao , Wang Ming Xiao , Li Sheng Ting
Published: July 2020

With the development of smart city, the concept of smart development is integrated into the construction management, so as to promote the smart development of construction and improve the efficiency of construction management. This paper discusses the application prospect of GIS-BIM integration technology in construction schedule management, site material management and safety management of construction personnel. At the same time, it looks into the application trend of gis-bim integration technology and global wide area network, Internet of things, virtual reality and other emerging technologies in the integration of building construction management, so as to promote the intelligent and visual management development of gis-bim integration technology in building construction management.
Fractional Porous Medium Equations to Non-Darcian Flow by Means of the Bernstein Polynomials
Authors: Deng Huilin , Li Lifeng
Published: July 2020

The Bernstein polynomials is used to develop the fractional differential Swartzendruber model in porous media. With the operator matrix of the Bernstein polynomials, the fractional differential Swartzendruber equation is transformed into the products of several dependent matrixs which can also be regarded as the system of linear equations after dispersing the variable. By solving the system of linear equations, the numerical solutions are acquired. Some experimental data are provided to show that the method is computationally efficient and accurate.
Finite Element Analysis On Traditional Camber Snowboard
Authors: Jiang Chengkai (Kenny)
Published: July 2020

The main focus of this paper is to analyze the behavior of the snowboard under different circumstances including the materials and the ways it is being ridden. The shape of the snowboard determines the board’s dynamic characteristics and performance [1][2]. In this research, traditional camber snowboards are analyzed by applying finite element method. Two riding conditions including normal riding on the flat surfaces and rail riding and two different kinds of materials which are beech wood and fiberglass (E-glass) are combined to be analyzed. Analyzing how the snowboards behave under different conditions allows designers to understand what they should modify to optimize the performances of the snowboard. It also gives the manufacturers a better understanding of what kinds of materials they should be using to ensure the long-lasting performance of the snowboard. Moreover, it helps riders to choose the most suitable snowboard for them based on their riding habits.
Dynamic Operational Characteristics for Condenser and Correlative Equipment
Authors: Wu Hao , Hou Yingzhe , Qian Feng
Published: July 2020

Effective control of condenser backpressure and outlet supercooling plays important role in thermal deaeration process. The back pressure model of condenser is established to analyze the influence of condenser pressure and temperature on circulating water flow, circulating water temperature and suction capacity of air ejector. The dynamic control characteristics and ability of the above factors to backpressure are analyzed.
Study on land port path optimization based on improved genetic algorithm
Authors: Zhang Jinyang , Ma Xiaobin , Huang Peijie
Published: July 2020

In the face of the development of supply chain globalization, Whether it is the choice of goods clearance or transportation mode, the establishment of land waterless port for product transportation, rapid customs clearance, convenient enterprises have a great role. Based on the analysis of the present situation and existing problems of land ports in China, the paper uses improved genetic algorithm to optimize the previous transportation paths. This paper analyzes the present situation and existing problems of waterless ports in China so as to optimize the previous transportation paths by using improved genetic algorithm. Through continuous iterative optimization, the collection paths are shortened and the no-load rate is reduced, so as to make full and reasonable use of transport vehicles, provide better service for enterprises and reduce more costs for waterless ports.
Optimization analysis of online marketing strategy based on the regression prediction model
Authors: Yang Jingya , Xiao Xiwang , Zhang Xianfeng , Wen Bin , Zhang Yuehua , Guan Jinqiu , Li Lan
Published: July 2020

In response to the three new product sales recommendations of the Amazon online market “Sunshine”, based on the data set provided by the enterprise data center, the data in the NLP feature package is preprocessed in Python, and the AHP model is established to measure and establish the data. This experiment according to the quarterly time series ARIMA model to forecast the product sales, and then through the standardization of OLS regression model to predict the trend of the development of products. The results showed that customer text reviews were an important reference for the sunshine company and found that microwave oven sales increased by an average of 6.28%, while sales of baby pacifiers and hair dryers increased by an average of 1.02%. This experiment based on this, puts forward the corresponding marketing strategy. Online marketing strategy can pay more attention to the customer’s comments, make updates on the features of the product, the use of to meet customer demand. The study enriches the existing research results, and the sun of the company’s sales strategy provides feasibility suggestions, thus has important theoretical significance and practical value.
Robustness analysis of road networks
Authors: Yu Yi , Wang Liang , Liu Mei
Published: July 2020

Damage events with difficulties to foresee are challenges to road networks especially under the background of a complex social environment. Robustness is critical in dealing with particularly high impact low chance events. In this paper the robustness of a road network is quantified to identify the weaknesses in the form of a road network. Theories of topology, structural vulnerability and road traffic are utilized in this paper. Transmittance of actual traffic flow is considered for the function evaluation of a network. This paper proves that the road networks has the weakness of single points or multi-point. If there is congestion, it may cause great functional loss to the local or the whole road network. Findings in this paper are strong supportive points of research for the propagation of more delicate-designed and form-improved road networks in urban areas. Adaption of the current work can be made when various practical cases are involved.
Application of P-median Method in the Location of Logistics Nodes
Authors: Tang Changyu , Tang Hongjuan , Jia Anzhen , Yin Wang
Published: July 2020

The location of logistics nodes and the concept of P-median method are analyzed in detail. In view of the problem of logistics node location, using P-median theory model, using greedy take-away heuristic algorithm, the Jinan A fruit and vegetable company provides a precise algorithm on the location of logistics node in Jinan. Realizes the rapid solution of the model, removes unqualified address from multiple candidate addresses, and selects the optimal logistics node location option.
A Preliminary Study on the Architectural Design of Chinese Hospitals in Virus Era
Authors: Cui Zhang
Published: July 2020

After the new Corona Virus Disease 2019 (COVID-2019), we have many new ideas for architectural design, more emphasis on epidemic prevention issues, designers in the functional design to meet the needs of medical staff and patients to use the design of the hospital, The assembly of hospital buildings is not only a transformation of construction methods, but also an upgrade of design concepts, which is a direction for future hospital development.
The Practice and Enlightenment of Architectural Renovation and Urban Renewal in the Netherlands
Authors: Jing Liping , Sun Leilei , Zhu Fengji
Published: July 2020

With the development of local urban renewal in the Netherlands, Dutch architects as Rem Koolhass, Francine Houben and Kees Kaan, etc. have showed rich practical experiences. As a result, the architectural renovation and urban renewal have presented a thriving scene. In this article, the types of urban renewal in the Netherlands are classified as three main categories: regional renewal, architectural heritage refurbishment, and adaptive reuse [1]. From the perspective of types to strategies, this study analyzes typical cases including the Westerpark West, Speelhuis theater, Timmerhuis and Villa Industria and so on, exploring the role of Dutch architects, the method of transformation and sustainable meaning of urban renewal. The research tries to summarize the Dutch mode and experiences, providing a new perspective and methodology for relevant transformation practices of urban renewal in China.
Study on Technical Standards Implementation Benefit Evaluation Practice
Authors: Hu Yuan , Tang Chenghui , Liang Cai
Published: July 2020

This paper has successively analysed and compared the practice of the United Kingdom, Germany, France, Canada, Japan, ISO and other countries and organizations in the evaluation of standardization economic benefits. And then a new method is proposed for large enterprises to carry out technical standard implementation benefit evaluation. Finally, case study for power company A and B validates the effectiveness of the proposed method.
Research on The Layout of Express Delivery Outlets in Jinan City
Authors: Zhang Yu , Su Mingyue , Cai Chuge , Liu Ziye , Zhang Dongli , Han Lulu
Published: July 2020

The layout of express delivery outlets is the key content of express delivery network organization. The organizational construction of a regional express network should consider multiple aspects, including the number of outlets, the location of outlets and the size of outlets. The construction level of express delivery outlets is directly related to the success of the future development of joint distribution model. This paper analyzes the factors that affect the number and location of express outlets in Jinan. And this paper obtains the distribution of express outlets in Jinan city by establishing mathematical model.
The Influence of Control Point Distribution of Unmanned Aerial Vehicles for the Results of Aerial Stitching
Authors: Hsu Chun-Li , Huang Hsiu-Hui
Published: July 2020

Unmanned aerial vehicles are an important development direction for today’s aviation telemetry technology, and have gradually become an essential technology for three-dimensional space acquisition. To date, the flight stability of unmanned aerial vehicles has been greatly improved, and space positioning is miniaturized, which ensures the UAV to play the most role in battery life, image real-time transmission, high-risk area detection and other occasions. In the past, natural disasters relied on traditional technology to obtain local conditions, thus, it was impossible to obtain immediate on-site information. However, the immediacy and convenience of unmanned aerial vehicles have been used to grasp the immediate situation of disaster relief sites, providing information for substantial benefits to disaster relief related units. In this study, Pix4Dmapper image processing software is used to quickly create orthophotos, thus, three-dimensional terrain elevation models of stereoscopic view and terrain data can be constructed. The captured images are spliced through the software, and the measurement accuracy of the aerial stitching images is discussed according to the different distribution positions of the control points. The results show that the number of control points is too small to improve accuracy. Regarding the study area, the optimal distribution route of 20 control points is the best. In more complex terrain, the control points should be selected at locations that contain various elevation changes. If it is not possible to evenly arrange the control points, it is recommended to select the circular route method.
Research and Design of Operation Mode and Risk Control Model of Finance
Authors: Yu Ziqiang , Wang Jiahui , Qin Liwei
Published: July 2020

The finance warehouse is a kind of service innovation of logistics and finance integration, and its innovative operation mode provides a new channel for SME financing. Firstly, the risk control model of finance warehouse is studied, designed and tested; on the basis of controlling regulatory risk and credit risk, the efficiency coefficient method of evaluation model is adjusted and improved; then the process of operation mode and the characteristics of each mode are studied and designed.
Research on Performance Evaluation System of Innovative Pharmaceutical Enterprises Based on Balanced Scorecard——Taking CCS1 WuXi AppTec as an Example2
Authors: Wang Yan , Liu Jiaan
Published: July 2020

With the reform of medical system, China’s pharmaceutical industry has entered a period of adjustment and transformation with steady development. The comprehensive performance evaluation of pharmaceutical companies is conducive to understanding the overall operation and development potential of the pharmaceutical industry in China, and has reference significance for the decision-making of all stakeholders. Based on the balanced scorecard, this paper designs a comprehensive performance evaluation system at the financial and non-financial levels, using scientific and effective evaluation methods to analyse the performance of pharmaceutical industry companies, which will play an important role in improving the comprehensive performance evaluation of pharmaceutical industry companies.
Comprehensive Evaluation on Safety Management of Road Dangerous Goods Transportation Enterprises Based on Multi-level Gray Relational Analysis
Authors: Wang Li , Jin Chunling , Li Chuanghong
Published: July 2020

It is helpful to improve the safety management level of enterprises to carry out the comprehensive evaluation on safety management of the road transport enterprises of dangerous goods, and to reduce road safety accidents. Based on the analysis of the risk factors of road transport of dangerous goods, this paper constructs a comprehensive evaluation index system for the safety of the road transport enterprise with the AHP method, and gives the weight of each evaluation index. Combined with the instance, the correlation size between each evaluated enterprise and the virtual “best enterprise” is calculated by using gray relational analysis model, so as to identify the pros and cons of the safety management level of each evaluated enterprise, and provide reference for comprehensive safety evaluation of road transportation enterprises of dangerous goods.
Comparative Analysis of the Mechanism of Engineering Project Management Standardization
Authors: Liu Longhua
Published: July 2020

With the improvement of engineering project performance and the need for theoretical innovation, the importance of standardized research on engineering project management has become increasingly important. Based on the results of the questionnaire survey, and on the basis of testing the reliability and validity of the questionnaire, the hierarchical regression analysis was used to study the mechanism between the influencing factors of engineering project management standardization and process performance, cooperation performance, knowledge accumulation, and engineering project performance. And test the hypotheses. In order to further improve the effect of engineering project management, it is quite necessary to carry out research on engineering project management. However, due to the lack of a substantial amount of substantial research in the actual research process, we have mainly carried out in-depth research on engineering project management standardization.
Genetic Algorithm for Optimizing Components of Mine Tailings Curing Agent
Authors: Cui Yiyuan , Mei Guodong , Wang Shan
Published: July 2020

Mine tailings harmless disposal is priority research in mining industry. Although a number of tailings disposal methods have been developed in the past, surface stacking still remains a major challenge in engineering. A key to realizing mine tailings surface stacking is developing high efficient curing agent to enhance the strength of consolidated tailings. In this study, an optimal approach based on genetic algorithm is developed for determining the best ratio of components. The proposed optimal approach succeeds in improving the compressive strength of consolidated tailings compared with orthogonal test. In addition, the developed optimal approach takes less test time than orthogonal test, which saves materials and shortens experimental time. The results indicate that a better compressive strength of consolidated tailings is achieved by the optimal curing agent based on genetic algorithm.
Transport Waste Separation and Recovery Trajectory Judged Based on Dijkstra’s Algorithm
Authors: Sun Yanbin , Shen Penglin , Jiang Huimin , Zhang Yuehua , Guan Jinqiu , Li Lan
Published: July 2020

Urban waste classification and recycling is an important research node in people’s livelihood, which is related to the corresponding relationship between efficiency and quality. The optimization of the recycling transportation path means that the cost is less. In the process of garbage transportation classification and recycling, optimizing and merging the routes of garbage transportation based on Dijkstra’s algorithm can optimize the shared transportation resources, to achieve the result of saving operating costs. The immediate transportation recycling event is planned as the path planning optimization. Multi-source multi-object and multi-path planning problems, and rehearse the optimization model of the total length of the transport path set without repeated paths. When the scale of the transportation and recovery network grows to a set value, it is difficult to achieve a theoretical solution by accurately calculating the optimal value of the model through an optimization algorithm. An optimal path set selection algorithm based on a random walk is feasible. The effectiveness and operability of the method are verified by small experiments and simulation experiments. The path is the shortest, and compared with the summation algorithm, it not only has high accuracy, but also has high execution efficiency.
Research on the test method for composite threshold of subway platform door
Authors: Feng Shuangchang , Niu Kuangye , Zeng Xiaoyi , Yang Yuqing
Published: July 2020

At present, subway platform doors have become the standard configuration of Chinese subways due to the advantages of energy saving, environmental protection, passenger safety, and improvement of the waiting environment. In order to solve the problem of insulation failure of traditional platform door thresholds, threshold manufacturers use composite materials with their own insulating properties to manufacture composite thresholds. Instead of the aluminium alloy and stainless steel structures commonly used in the industry, the composite threshold uses polymer composite as the basic carrier, and then covers the aluminium alloy panel on the surface of the basic carrier. The non-metallic material of the composite threshold has a unique advantage in insulation, but its mechanical properties still need to be verified by experiments. In view of the lack of test method for the compound threshold of subway platform doors, this paper formulates the method for the composite threshold of platform door based on the test method of escalator steps. PWS-20 electro-hydraulic servo cascade fatigue testing machine was used as the test equipment. The static load test and dynamic load test were carried out on the composite threshold samples respectively. When a force of 1000N is applied for the static load test, the maximum deflection value is 0.919mm. After 1 million cycles of dynamic load test with a non-interfering resonance force wave with a frequency of 5 Hz and a pulsating load between 50N and 1000N, no cracks were observed in the sample. For the composite threshold made of other materials, this test method can also be used to carry out static load test and dynamic load test.
Study on Material Model and Pressure Distribution Characteristics of Off-highway Minning Dump Truck Bucket
Authors: Hao Ni Ni , Jiang Xue
Published: July 2020

In view of the existing problems in the calculation method of the external contour of the material accumulation of the off-highway mining dump truck bucket, the reverse engineering technology and the 3D laser scanning method are proposed to accurately obtain the 3D model of the material distribution in the truck bucket. Based on the three-dimensional solid model of the material, the pressure formulas of the front plate, the side plate and the bottom plate of the bucket are derived by the force analysis method based on the thin-layer element method. References for the structure design and performance analysis of dump truck bucket are provided.
Particle swarm optimization for wavefront correction in ophthalmic applications
Authors: Beeck Andreas , Muckenhirn Stefan , Herkommer Alois
Published: July 2020

Many optical systems require the correction of the cumulative wavefront error of the system for performance optimization. In ophthalmology the wavefront error of the eye corresponds to the visual defect and can be measured up to high-order aberrations today. Lower orders of the wavefront error are usually corrected with spectacles, contact lenses or refractive surgery. In this paper we apply an optimization method called particle swarm optimization to calculate the optimal correction for visual defects based on measured high-order wavefront results. It is shown that an optimized conventional correction and in particular an extended wavefront correction including higher orders yields a better result for the visual Strehl ratio, as compared to a simple conjugate correction scheme.
The efflorescent carbon allotropes: fractality preserved blooming through alkali treatment and exfoliation
Authors: Swapna M S , Sankararaman S
Published: July 2020

The work reported in the paper elucidates morphological modification induced nanoart and surface area enhancement of graphite, graphene, and soot containing carbon allotropes through ultrasonication and alkali-treatment. The field emission scanning electron microscopic (FESEM) analysis of the samples before and after exfoliation reveals the formation of brilliant flower-like structures from spindle-like basic units due to Ostwald ripening. The x-ray diffraction analysis of the samples gives information about structural composition. The fractal analysis of the FESEM images indicates a multifractal structure with the dimensions—box-counting dimension D0 (1.72), information dimension D1 (1.66), and correlation dimension D2 (1.63)—preserved upon exfoliation. The process of ultra-sonication assisted liquid phase exfoliation resembles blooming as if the carbon allotropes are efflorescent.
Tame topology of arithmetic quotients and algebraicity of Hodge loci
Authors: Bakker B. , Klingler B. , Tsimerman J.
Published: July 2020

In this paper we prove the following results:

1
)

1)

We show that any arithmetic quotient of a homogeneous space admits a natural real semi-algebraic structure for which its Hecke correspondences are semi-algebraic. A particularly important example is given by Hodge varieties, which parametrize pure polarized integral Hodge structures.

2
)

2)

We prove that the period map associated to any pure polarized variation of integral Hodge structures

V

\mathbb {V}

on a smooth complex quasi-projective variety

S
S

is definable with respect to an o-minimal structure on the relevant Hodge variety induced by the above semi-algebraic structure.

3
)

3)

As a corollary of

2
)

2)

and of Peterzil-Starchenko’s o-minimal Chow theorem we recover that the Hodge locus of

(
S
,

V

)

(S, \mathbb {V})

is a countable union of algebraic subvarieties of

S
S

, a result originally due to Cattani-Deligne-Kaplan. Our approach simplifies the proof of Cattani-Deligne-Kaplan, as it does not use the full power of the difficult multivariable

S

L
2

SL_2

-orbit theorem of Cattani-Kaplan-Schmid.
A second-order numerical method for the aggregation equations
Authors: Carrillo José , Fjordholm Ulrik , Solem Susanne
Published: July 2020

Inspired by so-called TVD limiter-based second-order schemes for hyperbolic conservation laws, we develop a formally second-order accurate numerical method for multi-dimensional aggregation equations. The method allows for simulations to be continued after the first blow-up time of the solution. In the case of symmetric,

λ
\lambda

-convex potentials with a possible Lipschitz singularity at the origin, we prove that the method converges in the Monge–Kantorovich distance towards the unique gradient flow solution. Several numerical experiments are presented to validate the second-order convergence rate and to explore the performance of the scheme.