bluuebunny/crossref_metadata_2025 huggingface dataset:
Effect of non-isothermal flow on chloride ion transport in saturated concrete
Authors: Peng Chen , Wu Qing , Xu Jun
Published: April 2021

The presence of a temperature difference changes the mode of motion of the fluid. The macroscopic motion of the fluid causes the relative displacement between the various parts of the fluid, which in turn affects the transfer of temperature in the medium. To investigate the effect of temperature transfer coupled fluid motion on chloride ion transport in concrete, a mesoscopic model of chloride ion transport in non-isothermal flow of concrete was established and compared with experimental data. Based on the finite element software, the influence of temperature transfer on the internal fluid motion and chloride ion transport of concrete was analyzed. And the effect of convective motion of fluid on the temperature transfer in concrete was studied. It is found that when the heating time is the same, the dynamic viscosity of the fluid in the concrete decreases with the increase of temperature; the chloride ion concentration increases with the increase of temperature at the same depth of concrete; when considering the influence of laminar flow, the temperature is transmitted faster in the concrete and exhibits uneven diffusion from high temperature to low temperature; non-isothermal flow promotes the diffusion of chloride ions in concrete, and the higher the temperature.
Technical Characteristics and Energy Performance of Double Skin Faces: A Review
Authors: Xu Cui , Xi Qiao , Ma Qingsong
Published: April 2021

Double Skin Facades (DSFs) have the advantages of heat preservation, heat insulation, noise reduction and energy saving. Therefore, DSFs are gradually developing into a new direction of environmental protection and energy saving of the curtain wall. This article mainly introduces the technical characteristics of DSFs from two aspects: the geometric structures of the hot aisles and the ventilation modes. And this article systematically reviews more than twenty articles which have dealt with the energy performances: thermal performances and ventilation performances. The paper finishes with some conclusions: The unique structure of DSFs makes DSFs outstanding in terms of energy saving, ventilation. However, DSFs also have some shortcomings: the initial investment and maintenance costs are relatively high, the fire protection design is relatively difficult, and the industry lacks industry standards. Therefore, it is necessary to estimate the overall energy-saving effect in advance, continue to in-depth optimization research on the engineering application value of DSFs, and ultimately bring good social and economic benefits.
Experimental study on bond strength of joint surface of double-sided laminated shear wall
Authors: Yiwei Yuan , Baijian Tang , Hongming Li , Chenchen Ding , Sheng Gu
Published: April 2021

In order to study the bonding strength of the joint surface of the double-sided laminated shear wall, a double-sided laminated shear wall specimen was designed and fabricated, and then the the bars were planted in the precast layer and the middle post pouring layer of the specimen, and the normal tensile bond strength of the joint surface was tested by the drilling core planting bar drawing method. The results show that the bond strength of the joint surface of double-sided laminated shear wall can be detected by the method of drilling core planting bar drawing, and according to the cross section of the core sample, it can be known that the joint surface is indeed the weak part of the laminated member, and it is suggested that the bond strength of the joint surface of the double-sided laminated shear wall should be tested by planting steel bars in the middle post-cast layer.
Screening and application of microbial inoculants for sludge composting in expressway service area of northwest China
Authors: Zhao Jing , Wang Xiao wei , Fan Hua , Fan Chun ping , Shao She gang , Xie Jian bo
Published: April 2021

Taking sludge in northwest China’s expressway service area as the research object, four dominant strains, including Bordetella sp. M05, Ochrobactrum sp. M06, Bacillus subtilis M07 and Staphylococcus sciuri M09, were obtained through specific screening. These microbes were prepared into inoculants and effectively promoted sludge composting. The time for the fermentation temperature of the composting process to reach 50°C was 3 days earlier than that of the control group. The high temperature (>50°C) lasted for 12 days and the highest temperature reached 63.5°C. After composting, the product was dark in color, free from odor, and the contents of organic matter, nitrogen, phosphorus and potassium increased by 44.1%, 125.9%, 311.1% and 269.2%, respectively, which made the composted product meet standards of GB/T 23486–2009 Sludge for Landscaping.
Effects of pre-charge temperatures on gas production and electrochemical performances of lithium-ion batteries
Authors: Xiaoyan Shi , Leilei Ma , Jiantao Wang
Published: April 2021

Pre-charge as a key step in the battery manufacture processes, which has a great impact on the film-forming properties and electrochemical performances, especially the Li-rich system batteries. As a key influence factor, it is necessary to clarify the effect of pre-charge temperature on battery performance. In this paper, we mainly studied the influence of different pre-charge temperatures (25°C, 40°C, 60°C) on the gas production and electrochemical performance of the batteries. The results show that the increase of the pre-charge temperature will result in the increase of gas production, and the gas components are mainly CO2, H2. After the long-term cycle, the sample under 40°C maintains the highest capacity retention rate, and as the pre-charge temperature increases, the median voltage of the battery can be effectively increased. In addition, compared with room temperature pre-charge, high pre-charge temperature samples have more excellent rate performance.
Study on water resources and water environment in urban agglomeration
Authors: Liu Manli , Wang Ying
Published: April 2021

This study is the result of analysis on the influencing factors of water resources and water environment in Beijing-Tianjin-Hebei urban agglomeration during 2010–2019. Based on the spatial and temporal distribution of water resources, the effective utilization rate and recovery rate of water resources, analysis of groundwater exploitation, reservoir construction, surface water pollution, soil erosion, etc., the overall situation of water resources and water environment in the Beijing-Tianjin-Hebei urban agglomeration is obtained, and the water resources are further effectively controlled to strengthen the security of water environment.
Real-time evolution of oil shale meso-structure under triaxial stress condition
Authors: Tang Haibo , Kang Zhiqin , Wang Kun
Published: April 2021

It is significant to research the mechanical properties and micro-fracture evolution characteristics of oil shales with different bedding directions under the condition of in-situ triaxial stress loading for understanding the internal micro-characteristics of oil shales. Triaxial stress loading tests of cylindrical oil shales were carried out in two loading directions perpendicular to and parallel to the bedding, which is the S1 and S2 samples. Our results demonstrate that the oil shales are typical anisotropic and brittle fracture characteristics. The triaxial compressive strength of S1 is higher than that of S2, but the elastic modulus is almost the same. Based on the reconstructed 3D-CT image, we analyzed the dynamic evolution law of the fracture inside the sample in the horizontal and vertical directions, and obtained the distribution of the fracture in the loading process, finally revealing the internal micro-characteristics of oil shales under the different loading conditions.
Feasible analysis of pulsating heat pipe applied to proton exchange membrane fuel cell
Authors: Shang Fumin , Yang Kangzhe , Liu Chaoyue , Yang Qingjing , Liu Jianhong
Published: April 2021

Proton exchange membrane fuel cell (PEMFC) has the advantages of high energy efficiency, clean, pollution-free, fast start-up and noise-free, but its thermal management problems still restrict the development and practical application of PEMFC. This paper analyzes the important influence of heat management on the working performance of proton exchange membrane fuel cell, and summarizes the structure principle and effect evaluation of thermal management system using heat pipe under the premise of simply summarizing the shortcomings of the thermal management system using conventional cooling method. By expounding the working principle and characteristics of pulsating heat pipe, and from the perspective of PEMFC internal structure and technology, the feasibility of applying pulsating heat pipe to PEMFC thermal management system is analyzed, with a view to developing pulsating heat pipe-type PEMFC thermal management technology with compact structure and excellent performance.
Study on application technology of pulsating heat pipe
Authors: Liu Jianhong , Shang Fumin , Yang Kangzhe , Liu Chaoyue , Wu Yong
Published: April 2021

Pulsating heat pipe(PHP) has many advantages, such as small volume, simple structure, low cost, good heat transfer performance, it have great potential in the application of refrigeration, aerospace, waste heat recovery and low - grade energy utilization. Based on the analysis of a large number of research results at home and abroad, the application status of pulsating heat pipe technology is summarized in this paper, which can provide scientific guidance for the design, operation and large-scale application of pulsating heat pipe.
Research on Nonlinear Characteristics of Hydro-pneumatic Suspension with Hydraulic Preload
Authors: Gao Huichao , Chen Xinyuan
Published: April 2021

The hydro-pneumatic suspension of special vehicles is mainly used to transmit vertical force and ease the impact and vibration caused by uneven road surface. As a new type of elastic element, the Hydro-pneumatic suspension generally uses inert gas or nitrogen as the elastic medium and hydraulic oil as the force transmission medium. Compared with ordinary leaf springs and coil springs, it has the advantages of small size and strong load-bearing capacity. This paper compares the Hydro-pneumatic suspension with hydraulic preload under different conditions and finds that under reasonable parameters, the hydro-pneumatic suspension can provide more stable performance.
Analysis of key issues in electric-hydrogen coupled operation
Authors: Xiaochen Wang , Mengxuan Lv , Yifan Fu
Published: April 2021

This paper conducts an in-depth analysis of the electricity-hydrogen coupling under the high-permeability renewable energy scenario, and further proposes that the production of hydrogen from electrolyzed water is a key link in the electricity-hydrogen coupling under the high-permeability renewable energy scenario. Analysis of key issues in technical routes and other aspects, and finally put forward development suggestions for the development of hydrogen energy under the scenario of high-permeability renewable energy.
Construction and performance analysis of data warehouse based on ship propulsion system
Authors: Hu Qi , Chen Yutao , He Yuqian
Published: April 2021

A large number of operation data will be generated in the process of ship propulsion system operation. Aiming at the processing, analysis and application of these operation data, a data warehouse for propulsion system is constructed based on the operation data of a ship, and the multidimensional analysis and result display of data are realized by combining OLAP technology with visual analysis software tableau. On the basis of the data warehouse, the soft sensing of parameters is applied to the data warehouse. Based on the soft sensing data, the hydrodynamic characteristics of the propeller are studied, and the hydrodynamic characteristic curves of the propeller are obtained. The research of ship propulsion system based on data warehouse provides support for the comprehensive information of propulsion system data.
Dynamic vibration absorption design and parameter analysis of oil tank wall of transformer
Authors: Zhang Hong , Cao Meigen
Published: April 2021

Taking a 10kV test transformer as the research object, based on the analysis of transformer vibration and noise vibration sources, the oil tank model of the test transformer is established firstly, and the vibration mode analysis of the oil tank is carried out, and the typical vibration modes of transformer oil tanks with different thicknesses are obtained Then, according to the characteristics of vibration and vibration source of distribution transformer tank wall, the design method and parameter optimization analysis of transformer tank wall vibration absorption are carried out. The analysis shows that the principle of dynamic vibration absorption is clear, and the vibration of the box wall can be effectively controlled with 76% vibration reduction efficiency under the condition of reasonable arrangement of vibration absorption devices and parameter selection. The vibration control effect of vibration absorber increases with the increase of mass ratio between vibration absorber and transformer tank wall. When the mass ratio is determined, the closer the stiffness of vibration absorber is to the optimal stiffness, the better the vibration reduction effect will be.
Numerical Simulation of Wind Turbine Aerodynamic Characteristics under Wind Shear Based on Lattice-Boltzmann Method
Authors: Yuan Chengdong , Wang Jinlong , Pan Yueyue , Chen Hui , Zhang Xiaqi
Published: April 2021

In order to study the influence of wind shear on the aerodynamic characteristics of large wind turbines, taking the 5MW wind turbine blade model published by NREL as the research object, large eddy simulation (LES) of wind turbines was carried out by using XFlow fluid simulation software based on Lattice-Boltzmann method (LBM). WALE turbulence model was used to study wind shear at 3, 11.2 and 25m/s wind speeds. The effect of factors on the axial thrust and torque of wind turbines is compared with the data published by NREL. The results show that the XFlow software based on LBM and LES method has good capturing ability for the eddy wake of wind turbine; wind shear causes the airfoil section of each section of blade to deviate from the best designed attack angle in theory and results in a decrease in torque applied to the wind turbine.
Improvement of Dynamic Modelling for Single-phase Heated Tubes
Authors: Zhehua Du
Published: April 2021

To improve the currently available multi-segment lumped parameter models, a new dynamic mathematic model for single-phase heated tubes is established by employing dynamic equations instead of the traditional static equations for calculating the heat transfer across the control volume’s tube wall. Through separating the temporal and spatial terms of the partial differential equations, and combining both lumped and analytical methods, an analytical solution for the temperature distribution of the steam and water in the tubes is derived. Then, by integrating the elemental volume equations, dynamic equations for the heat release of the tube wall are achieved. The improved model, which can be explicitly solved, is more stable and has much wider applicability. After applying the improved model to an ultra-supercritical boiler superheater, the results show that the response characteristics for inlet temperature step change are significantly improved, and the results during the puredelay periods are in accordance with those of the distributed parameter models. Compared with traditional multi-segment models, the improved model can achieve higher precision even with less segments. Besides, the transport delay characteristics of water or steam within tubes can be analyzedmore accurately with the improved model.
Research on Risk Formation Path of Coal Enterprises based on SEM Method
Authors: Tang Yiyong , Li Wenxing
Published: April 2021

There are some problems in China's coal mining, such as limited mining technology, low degree of mechanization, lack of effective safety facilities, imperfect accident early warning mechanism and untimely response, which make the production safety problems perplex coal enterprises for a long time. This paper uses AMOS and SPSS 19.0 to analyze the coal risk data. The first is to establish the research hypotheses and conceptual model, set up structural equation model and path map. Secondly, the structural equation model and path coefficient are obtained by AMOS software, and the model is identified, evaluated and modified. Finally, the paper analyzes the direct effect and indirect effect between latent variables, latent variables and observed variables, and clarifies the risk factors of coal mining enterprises and the path of risk formation.
Fluid structure interaction based structure stress and modal analysis of a flat type solar panel supporting system
Authors: Liu Handai , Zhang Piao , Lai Zhenqiang , Dong Xiaofeng , Wang Zhicheng , Zhou Shumin
Published: April 2021

Solar panel supporting systems are often affected by strong wind loads, especially in typhoon-intensive areas such as Southeast Asia. This paper focuses on the study of flat-panel solar energy system. The numerical model of solar panel supporting system has been built by using the fluid flow control equations. Firstly, the numerical simulation of aerodynamic characteristics of the solar panel supporting system are conducted, and then the pressure results gained from CFD are loaded and coupled to the front and back of the solar panels. Lastly, the stress, strain and the modal analysis results of the support system under four different directional wind loads are achieved. The conclusions include: (1) under the condition of same wind speed, the wind pressure and distribution of the solar panel are different with different wind directions, and the wind load perpendicular to the solar panel has the greatest influence on the solar supporting system. (2)The modal frequency of flat panel solar supporting system is little affected by wind directions and average wind pressure. In the structure design, low order vibration should be considered mainly in the supporting part of the system, while the high order vibration should be generally considered in vibrating risk of solar panel. (3)The first six modal frequencies coupled with fluid-structure interaction of the flat panel solar supporting system are all slightly lower than the free modal frequencies.
Research on The Evolution of High-tech Industry Competitiveness in Beijing-Tianjin-Hebei
Authors: Yanxia LI , Zhang Jie
Published: April 2021

From the perspective of ecological niche, this paper constructs the evaluation index system of the competitiveness of beijing-tianjin-hebei high-tech industry, and analyzes the competitiveness of beijing-tianjin-hebei high-tech industry from the perspectives of niche value, niche width and niche overlap. The results show that :(1) from the perspective of ecological niche, the niche value of the competitiveness of high-tech industries in Beijing, tianjin and hebei does not show an increasing trend with time, and the overall value of the niche is ranked from the largest to the smallest: Beijing, tianjin and hebei.(2) from the niche breadth, beijing-tianjin-hebei high-tech industry competitiveness niche breadth range as follows: 0.26-0.83, Beijing niche width of the widest, hebei niche breadth the narrowest, Beijing and tianjin hi-tech industry competitiveness niche breadth value reduced trend on the whole, hebei niche breadth on overall growth trend.
Benefit analysis and evaluation of virtual power plants considering electric vehicles
Authors: Caixia Tan , Zhongfu Tan , Jianbin Wu , Huiwen Qi , Xiangyu Zhang , Zhenbo Xu
Published: April 2021

Under the background of increasingly serious environmental pollution, virtual power plants have become an effective way to solve environmental pollution due to the characteristics of integrating a large number of clean distributed energy generation. At the same time, electric vehicles with dual attributes of power supply and load bring opportunities for the further development of virtual power plants. In this paper, the ideal matter-element comprehensive benefit evaluation model of virtual power plants is constructed by constructing the index system and weighting model of virtual power plants considering electric vehicles. The virtual power plants connected with different proportion of electric vehicles are taken as an example analysis. The results of the example analysis show that the comprehensive benefit of virtual power plants is the highest when the proportion of electric vehicles access reaches 120%.
Research on energy saving and emission reduction of urban transportation under the concept of low-carbon life
Authors: Zheng Guangyu
Published: April 2021

In response to the national concept of green and low carbon, the carbon emission analysis and peak prediction of transportation in 20 cities were carried out by using the carbon emission calculation model based on residents’ travel, and the quantitative effects of various improvement measures were evaluated. The results show that the urban transport structure and residents' travel distance are positively correlated with the urban carbon emission intensity, and the urban transport carbon emission in China will reach the peak around 2023. Accelerating the application of new energy, optimizing the urban transport structure, building a green transport system, and optimizing the urban transport line network all have good emission reduction effects.
Natural Gas Power Generation to Promote the Construction of Ecological City
Authors: Xie Mengfan , Zou Yanyan , Zhou Yi
Published: April 2021

As an unsustainable resource, it is of great significance to explore more efficient and low-carbon ways of using energy. With the fast development of China’s economy, most cities are faced with the pressure of ecological environment to varying degrees. The construction of ecological city is not only the need of ecological protection and improvement of natural environment, but also the requirement of urban development. Compared with coal-fired power generation, natural gas power generation has advantages in terms of environmental pollution, energy utilization efficiency and resource occupancy, and is one of the ideal energy sources for eco-city construction. However, at present, there are constraints such as lack of subsidy policy, high fuel price, dependence on import of equipment and high cost of construction and maintenance. In the long run, the development of gas-fired power generation industry should be actively and prudently promoted from the aspects of strengthening the construction of supporting facilities and the guarantee of gas source, perfecting the mechanism of electricity price, and increasing the localization rate of key equipment, so as to achieve the goal of optimizing industrial structure, saving energy and reducing emissions, and facilitating the construction of China’s ecological city.
An Empirical Study on the Impact of Environmental Regulation on the Efficiency of Green Technology Innovation
Authors: Min Wu
Published: April 2021

This paper uses two-stage super efficiency network SBM DEA model to calculate the efficiency of green technology innovation, and analyzes the spillover effect of three different environmental regulations, namely command control, market incentive and independent participation. The results show that the direct effect of the command control environmental regulation on the efficiency of green technology innovation is positive, the indirect effect and the total effect are negative; the direct effect, indirect effect and total effect of market incentive environmental regulation and independent participation Environmental Regulation on the efficiency of green technology innovation are positive.
Research on static force calibration technology of fatigue test system
Authors: Lu Liu
Published: April 2021

The fatigue test system is the main equipment to test the fatigue load performance of anchorage, but for a long time, due to the lack of calibration basis and the lack of effective traceability way, it is unable to calibrate the equipment. This paper analyzes the structure and working principle of the fatigue test system, and determines its measurement technical indicators and requirements through investigation and test verification. The calibration method of static force value is studied and verified by experiments. The uncertainty of static force calibration results is evaluated, and the static force calibration technology of fatigue test system with uncertainty better than 0.50% is formed, which lays a good foundation for the calibration of this kind of equipment.
Research on electric power development and economic growth in Hebei Province based on business cycle analysis
Authors: Liang Miao , Chen Meng , Li Yan , Xu Xiaomin , Niu Dongxiao
Published: April 2021

With the improvement of China’s electrification level, the relationship between electricity power consumption and social economy development is getting closer. Under this background, in this paper, the business cycle analysis method is applied to the electricity power industry in Hebei Province, and the link between electric power generation and economic development is determined through the prosperity index. First of all, the steps and methods of business cycle analysis were introduced, and the time-difference grey correlation method considering the consistency of time series to screen indicators was put forward, thus to reduce the number of indicators. Next, Hebei Province was taken as an example, and its monthly data related to power generation and economic growth in the 10 years from 2009 to 2018 to was selected to build the business cycle indicator system, at last the composite prosperity index of Hebei Province in electric power industry was calculated. This research results manifest that it is feasible to apply the business cycle analysis to the power industry.
Modelling Natural Gas Energy Production of United States
Authors: Cai Yubin , Deng Yanqiao
Published: April 2021

In the transformation of the energy system, natural gas energy is regarded as a buffer energy. How to make a reasonable energy distribution and effectively predict its production is very significant. In the work of this paper, a grid-optimized fractional-order non-homogeneous grey model is used to predict the natural gas energy production in the United States and obtain reliable results. This paper first introduces the prediction method and prediction mechanism. Then the model is optimized to make the prediction effect more prominent. The natural gas energy prediction results show that this method has high prediction accuracy compared with other methods, which means that the method proposed in this paper can be used as an effective tool for short-term forecasting of natural gas production in the United States and play an auxiliary role in energy forecasting.
Research on Steering Stability Control Strategy of Four-wheel Independent Electric Drive Special Vehicles
Authors: Zili Liao , Xin Shu , Lichun Cai , Linyun Zhang
Published: April 2021

In order to solve the steering stability problem of a special four-wheel independent electric vehicle, a dynamic model of the vehicle was established to analyze the cause of vehicle instability. A steering stability controller was designed, which included the upper yaw moment controller and the lower driving force distribution controller. Based on the sliding mode control algorithm, the yaw moment controller determines the yaw moment required while the vehicle is moving by controlling the yaw rate and sideslip angle. Based on the safety distribution method, the driving force distribution controller selects the sum of tire utilization rate as the optimization function to realize the optimal distribution of yaw moment. Software of MATLAB/Simulink and CarSim were used to build a co-simulation platform, and the designed steering stability controller was analyzed and verified. The simulation results show that the steering stability controller is helpful to improve the steering ability and handling stability of the vehicle in the extreme working conditions.
An improved ip-iq harmonic detection method
Authors: Guoqing Yang , Kai Yan , Deyi Wang , Yuan Chai , Xu He
Published: April 2021

The ip-iq harmonic detection method based on instantaneous reactive power has been widely used in active power filter (APF). However, the traditional ip-iq detection method has errors when the grid voltage is unbalanced and distorted. This paper proposes an improved ip-iq harmonic detection method, which uses adaptive notch filter (ANF) to extract the fundamental positive-sequence voltage signal, so that the phase locked loop (PLL) can still accurately obtain the phase information under bad grid conditions. At the same time, moving average filter (MAF) is used to replace low-pass filtering to reduce the detection delay. The simulation results show that the improved ip-iq detection method can accurately detect harmonic current under non-ideal grid voltage conditions, and has good dynamic characteristics.
Study on the impact of energy and environmental efficiencybased on DEA-ENDDF and Tobit model
Authors: Qin Xiaonan , Wang Yingchun
Published: April 2021

Based on the resource allocation effect, technological innovation effect and competition effect, this paper takes eight comprehensive areas as decision-making units, uses DEA-ENDDF method under the theoretical framework of total factor production with non-radial distance function, calculates energy and environmental efficiency through NDDF of MaxDEA software, makes hypothesis test, and uses Tobit model to analyze the influencing factors of energy and environmental efficiency, such as transportation foundation, economic structure, technological progress, external dependence, energy endowment, population density and other factors are analyzed by regression analysis. Finally, the conclusion is given, in order to explore useful conclusions and explore new ways of energy conservation and emission reduction.
Feature frequency extraction algorithm based on matching pursuit and its application in axis orbit
Authors: Li Weiguang , Zhang Xinxin , Li Zhen , Huang Jian , Cai Wenwei
Published: April 2021

Rotor displacement signal is an important state characteristic parameter of rotating machinery, which contains abundant operation information of rotating machinery. Aiming at the problem of purifying axis orbit in large -scale rotor test-bed, a new method of extracting the characteristic frequency and synthesizing axis orbit is proposed based on the matching pursuit algorithm (MP). In this paper, the sparse decomposition of signals in the algorithm is implemented by MP algorithm. The algorithm can accurately extract single or multiple feature frequencies. The purified curve is clearer and more efficient. Fault types can be found by extracting different characteristic frequency synthetic axis trajectories, so as to understand the operation status of the large-scale rotor test-bed.
Application of modern supply chain in 5G scenario
Authors: Li Runqi , Wang Zhisen
Published: April 2021

The continuous innovation and development of information technology and information infrastructure has driven the evolution of the supply form, and with the emergence of 5G, a mobile integrated communication system that includes communication access, interconnection, and connectivity of things, it has now evolved to a modern supply chain of the social organization collaborative type. This paper briefly describes the process of supply chain development, examines the role of communication technology in driving supply chain development, discusses the relationship between modern supply chain and social development and the support of 5G for modern supply chain, and illustrates the application of 5G in modern supply chain scenarios by reducing information time lag in market-side scenarios as an example.
A new expression to predict secant rotational stiffness of spudcan in undrained soils
Authors: Lin Wenlong
Published: April 2021

The nonlinear behavior of spudcan foundation will lead to the decrease of the rotational stiffness of the spudcan, leading to the increase of the stress at the critical member of the offshore jack-up drilling platform. Secant rotational stiffness is used to represent the value of rotational stiffness of linear foundation model when the soil changes from elastic to elasto-plastic and then to plastic. In this paper, the “wished in-place” small strain finite element analysis (SSFE) analysis is used to simulate the load-displacement response of spudcans pre-embedded in the plastic soil, thus calculating the secant rotational stiffness of spudcans. New expressions of failure ratio and secant rotational stiffness are proposed with the coupling effect of horizontal force and moment taken into account.
Research on construction projects from a social network perspective: based on knowledge graph analysis
Authors: Deng Jiaojiao , Chen Chen , Gong Weichen
Published: April 2021

In order to comprehensively reflect the current status, research hotspots and evolutionary trends of research on construction projects from a social network perspective, 143 HJrelevant papers in the WoS database from 1999 to 2020 were taken as the research objects, and the bibliometric method and CiteSpace V were used to reveal the research development and evolution of the field during the 20 years and explore the future research trends. The study shows that the hotspots of construction project research from social network perspective include performance, governance, stakeholder management, risk management, and communication; research on construction project organizational network innovation, stakeholder risk and governance, BIM technology application, and social capital perspective to improve project organization become future research trends.
Application of information entropy and TOPSIS coupling model in impervious design of hydraulic engineering
Authors: Zhang Shu
Published: April 2021

The establishment of a scientific and reasonable mathematical evaluation model plays a vital role in the optimization of impervious design scheme of water conservancy projects. The steps of constructing the coupling model of information entropy and TOPSIS are analyzed. The seepage prevention design scheme of an urban artificial lake is comprehensively evaluated by using this model, so as to obtain the optimal scheme.
A review of current work in research of Trombe walls
Authors: Wang Xin , Xi Qiao , Ma Qingsong
Published: April 2021

Sustainable architecture and green building are recognized techniques to address the energy and environmental crises. In this regard, the Trombe Wall has also attracted attention for its potential ability to address the energy and environmental crises. Trombe Wall is regarded as a sustainable architectural technology for insulation. This article reviews the classification and configuration of Trombe Wall and the most relevant content of Trombe Wall research carried out in various countries over the past few decades. This review discusses the characteristics of the main subspecies of the Trombe Wall. In terms of content, according to the research methods of different types of Trombe walls, they can be divided into two categories: theoretical simulation research and experimental research. The advantages of this sustainable architectural technology have been highlighted, and future research questions have been identified.
A case based study of design strategies to explore the notion of age-friendly co-housing community
Authors: Ye Jingyi , Wu Zhengwang
Published: April 2021

Globally, the proportion of the older people population is growing and this will continue to rise. 1 out of every 4 people in cities will be an older person by 2050[1] (World Health Organization, 2007). An age-friendly co-housing is an sustainable community, considering long-term interests, age-friendly co-housing can not only reduce social welfare expenditure, but also give full play of older people’s positive impact in society. Age-friendly co-housing requires more theoretical support and practice. The case analysis of two co-housing projects for older people are from the United Kingdom (London) and the United States (Oakland). The article analyzes and evaluates the case studies by using the WHO domains (see Table 1) and then concludes the design strategies from three aspects- outer space, communal space, and private residential space. This essay endeavored to explore the potential of age-friendly collective housing for older people, that is to say, connect age-friendly concept which is a hot issue today with co-housing model to solve the current ageism and population aging problems. A single design method cannot satisfy older people’s psychic needs, therefore, this article provides age-friendly co-housing with authoritative scientific theoretical background of interdisciplinary as the data collected from diverse fields as architecture, ecology, psychiatry, ergonomics and human sociology.
Research on Risk Management of Green Supply Chain of Prefabricated Buildings Based on QCA
Authors: Yang Hongxiong , Ren Wanru
Published: April 2021

In the context of sustainable development, green supply chain, as a whole-process environmental management model, provides a good implementation path for the development and utilization of prefabricated buildings. However, the green supply chain operation of prefabricated buildings in a complex social network environment involves many risk factors, which seriously affect the realization of the green supply chain management goals. This research first identifies risk factors based on the perspective of stakeholders, and then uses fsQCA to analyze the risk factors in the green supply chain of prefabricated buildings, and identifies four configurations that lead to high risks in the green supply chain of prefabricated buildings. Risk is the main risk that leads to the risk of the green supply chain of prefabricated buildings. The types of core risks involved mainly include externality risks, organizational management risks, and manufacturing risks. This research provides an effective method for evaluating and reducing risks in the green supply chain of prefabricated buildings, and improves the effectiveness and accuracy of risk control by all participants.
Study on Prefabricated Firewall with Truss Load
Authors: Jinhu Yang , Guangbing Xu , Wen Jiang , Wei Zhai
Published: April 2021

In this paper, a prefabricated structure is used to study the main transformer firewall with truss structure of the substation. The beams, columns and wall panels of the firewall are prefabricated components, and the cast-in-place structure is used only at the top beam and column joints.
Study on the stability of highway slope in cold region under freeze-thaw cycles
Authors: Chen Hongyu , Yuan Xizhong , Liu Wenbo
Published: April 2021

Based on thermo-mechanical coupling and elastoplastic theory, a finite element (FE) numerical simulation was adopted to study the stability of slopes in cold regions under freeze-thaw cycles. And the prediction of slope landslide was also studied through the calculation of strength reduction coefficients combination. The result shows that the development of the slope vertical displacement under freeze-thaw cycles can be divided into two stages: rapid stage and stable stage. After combining the two reduction coefficients of cohesion and internal friction of the soil, the maximum vertical displacement on the top of the slope in this region can be calculated as a reference for predicting the slope landslides. Meanwhile, the corresponding safety factor of the slope in the cold region can be obtained according to the reduction coefficients. .
Research on Mud Pulse MWD Device for Mines
Authors: Jun Gao
Published: April 2021

As the core accoutrement of directional drilling construction, the measurement while drilling (MWD) device can be divided into three types due to the different data transmission methods: wired, mud pulse and electromagnetic wave. This paper used the mud pulse method to develop a mud pulse MWD device for mines, and the working principle of the mud pulse signal transmission, the signal encoding method and the structure of the device were described. Experimental research showed that the mud pulse wireless MWD device had the advantages of long transmission distance and strong working stability. At the same time, the device was not restricted by the drill pipe during operation, which could be combined with sliding orientation and rotary feed, and had great promotion and application value.
Research on the application of fuzzy comprehensive evaluation method in civil engineering project procurement
Authors: Yang Chunyan , Liu Qiang
Published: April 2021

In order to improve the effectiveness of performance evaluation of civil engineering project procurement, according to the characteristics of civil engineering project procurement management, the procurement performance evaluation method is established based on the fuzzy mathematics theory. Taking a civil engineering project procurement as an example, the implementation effect of the procurement performance evaluation of the civil engineering project is evaluated. The evaluation results are basically consistent with the actual situation, which verifies the effectiveness and reliability of the method. It provides an effective and reference solution for the practical application of procurement performance evaluation in other civil engineering projects.
Study on ventilation scheme and application during construction of high altitude gas tunnel
Authors: Zhengbo Dong , Shuang Cai , Juyi Hu , Liang Cheng
Published: April 2021

It is the key and difficult point to ensure the safety of tunnel construction by ventilation in high gas tunnel construction in high altitude and cold area. Taking ning-chan high gas tunnel as the research object, the ventilation of the tunnel is calculated, the ventilation parameters are optimized, the ventilation equipment is selected according to the calculation results, the location of the ventilation equipment is optimized, and the reasonable construction ventilation scheme is determined. The results show that through the design of the above ventilation scheme and the control of the site, it can not only ensure the ventilation demand of the super long and high gas tunnel construction in the high cold and high altitude area, but also ensure the tunnel construction in winter, and effectively save the construction ventilation cost.
Research on Existing Problems and Improvement Measures of Fabricated Composite Wallboard
Authors: Yu Ziyang , Hu Yuqing , Qin Changhao
Published: April 2021

In recent years, fabricated composite wall panels have been widely used in building materials markets at home and abroad, and their main advantages are convenient construction, low energy consumption, and heat and sound insulation. However, fabricated composite wall panels also have some common problems in practical applications, such as large dead weight, weak seismic performance, prone to cracks, and failing to meet the higher energy-saving requirements of thermal insulation external walls. This article analyzes the board material and overall structure of the fabricated composite wallboard, proposes corresponding solutions to make up for its weakness in some performance, and gives the specific construction process and accuracy requirements.
Research on Integrated Cooperative Design of Building Structure Based on Building Information Model
Authors: Peng Rulun , Liu Tianyi , Zhang Min
Published: April 2021

With the rapid development of the socialist market economy, the development of the construction industry and the information industry has become more mature and sound. However, the practical application of information technology in the existing construction industry still faces corresponding problems, lacking sufficient completeness and specificity. This article will specifically discuss and analyze the building structure integrated collaborative design program of building information model, in order to provide a foundation for the development of modern construction industry.
Risk assessment of washout by slope flow along long-distance-pipeline based on quantitative index cloud reasoning-integrated weighting
Authors: Zhang Manyin , Sun Zhizhong , Xie Rong , Ka Maocuo , Wang Shengxin
Published: April 2021

The washout by slope flow along long-distance oil & gas pipelines is a common geological hazard that occurs when pipelines pass through the alluvial-proluvial fan section of mountain piedmont. Accurate and effective evaluation of the risk of single washout by slope flow is an important basis for disaster prevention and control decisions. According to the characteristics of the lack of basic research data in the development area of washout by slope flow, the complexity of the risk assessment structure and the strong randomness and ambiguity of the multi-index system, on the basis of rapid acquisition of initial data of indicators through field survey, simple experiment and sampling analysis, a quantitative index cloud reasoning risk evaluation model for slope flow washout of pipeline was established by introducing single-condition and single-rule cloud reasoning with summation integration weighting algorithm, and carry out instance verification. The evaluation results of 11 samples showed medium and relatively high risks, and the overall distribution trend is relatively concentrated. Compared with the results obtained by the entropy weight-extension method and the standard recommendation method, the proposed method is more in line with the small-scale disaster background analysis and the reality of the study area, and it’s also more beneficial to ensure the safe operation of pipelines. In this method, the obtainment of the source data is reliable, objective, and the preprocessing is simplified, the index weighting and classification are more reasonable, and the evaluation process takes into consideration of both the randomness and ambiguity of the system, which improves the accuracy and effectiveness of the evaluation results. It also provides a new way of thinking to other related research.
Impact resistance analysis of grille dam based on fluid structure interaction
Authors: Zhu Jia
Published: April 2021

Aiming at the impact failure of debris flow grille dam, considering the interaction of boulder-debris flow slurry- grille dam based on SPH-FEM, this article analyzed the variation laws of velocity, impact force and support reaction before and after debris flow slurry and boulders passing through grille dam. The results show that: SPH-FEM coupling method can truly reappear the impact of debris flow on the grille dam; the velocity of debris flow slurry and boulder are reduced by nearly 60% after passing through the dam, and the effect is remarkable; debris flow slurry and boulder have secondary impact on the grille dam. In the first impact, the greater the radius of the boulder, the greater the impact force; in the second impact, the impact force has nothing to do with the radius of the boulder.
Research status and trend of comprehensive technology for Multi-storey transportation hub construction
Authors: Jing-xian Shi
Published: April 2021

With the development of China's transportation industry, a lot of expressways have been built, and Multi-storey transportation hubs are built for the interchange of high-speed. Due to the limitation of terrain and traffic, there are many spans in the interchange Multi-storey transportation hub, which has a tight construction period and a great difficulty in construction organization. This paper first sorts out the development and research of comprehensive technology of Multi-storey transportation hub construction at home and abroad, and then analyzes and summarizes the research of Multi-storey transportation hub construction at present, the application research of Swivel Construction Technology in hub project, and the application status of BIM Technology in Multi-storey transportation hub project.