bluuebunny/crossref_metadata_2025 huggingface dataset:
Study On Axial Clearance and Seal of Scroll Compressor
Authors: Wang Jianji
Published: June 2019

In order to reduce the leakage of the axial clearance, the sealing strip is mounted at the top of the scroll tooth. For achieving the axial displacement compensation seal, it is put forward to open a hole that it is in one side of the high pressure chamber at the bottom of sealing groove. The high pressure chamber gas is introduced into the bottom of the seal. It can form a pressure difference. The article begins with the design of sealing groove structure. The stress analysis was carried out on the sealing strip, and sealing strip was established displacement calculation model of change. Secondly, through the simulation experiment, the friction and wear properties of several kinds of seal materials are compared and analysed. To select PEEK as sealing strip material is the most appropriate. Finally, taking typical parameters of involute scroll compressor as an example, the compressive performance of scroll teeth with sealed structure and non-sealed structure is simulated. The results show that the sealing displacement and axial clearance are basically the same under the two schemes. The sealing scheme is proved to be feasible. This lays the foundation for the further study of the axial seal of the variable section scroll compressor.
Effect of gas flow rate on the double gas-assisted extrusion forming of plastic pipes
Authors: Ren Zhong , Huang Xingyuan
Published: June 2019

To overcome the extrusion problems of plastic pipes, the double gas-assisted extrusion method was used in this paper. To investigate the effect of gas flow rate on the double gas-assisted extrusion forming of the plastic pipes, the numerical simulations based on the finite element method were performed. Numerical results show that with the increase of the gases flow rate, the inner radius increases and the outer radius decreases, which lead to decrease the wall thickness of plastic pipes. At the same time, the flow velocity changes of melt under the different gases’ flow rate were obtained and compared. To ascertain the mechanisms of shrinkage phenomenon of wall thickness, the normal stress and first normal stress difference distribution nephograms of melt under the different gases flow rates were obtained. Results show that the normal stress effect of assisted gases on the melt is the main reason that the wall thickness is decreased by the larger assisted gases flow rates.
Digital Computational Design: Towards A Material Culture
Authors: Wang Chen , Feng Zhiyu
Published: June 2019

The purpose of this study is to explore the relational, complementary and speculative co-existence in the design methods of thinking modes which lie in ‘New Materialism’ and computational design and their influences on architectural design applications, urban design and morphological design. As the properties of materials can give impetus to urban development, urban development can also exert its influences on materials. Similar to the beginning of all construction activities, materials are also related to all fields of design and construction in a direct manner. Taking into account the influences of New Materialism, the author then started to examine the relationship between materiality and digital diagrammatic design again. Being a new type of biomass materials, the bio-plastic is becoming increasingly popular in urban design. The environmental problems brought about by the frequent use of petroleum-based plastic have been solved by bio-plastic successfully. The computational tools can be applied to regenerate urban. Also, the critical media of geometry can launch out a new dialogue between the material and urban design.
Application of Composite Shell Lining for Qingdao Metro Xizhen Station
Authors: Du Qing , Sun Shanzun , Wen Shuyi , Zhan Guyi , Li Yang
Published: June 2019

Combined with the composite shell lining design of Xizhen station of Qingdao Metro line1, application of composite shell lining in Qingdao Metro station is introduced. The composite shell lining technology is set forth from such aspects as Mix design, characteristic research, construction technology and quality control, test standard and construction matters of structure fibre concrete, as well as good result is obtained in the practice. This paper provides some reference for the design and construction of similar tunnels.
Method of Comprehensive Risk Management for Satellite Transportation
Authors: Hongxian Zhong , Shuang Zou , Lei Zhang , Yibo Wang
Published: June 2019

Satellite transportation is the special link in the development of satellite. It’s different to the constant and controllable environment in building. Due to the large geographical area, complex climatic conditions, limited protection of packing box of satellite, and many burst links in the process, these are many risk items in satellite transportation and the risk items are all highly hazardous. Transportation has critical influence for the development of satellite.

This paper analyzes the timing and methods of risk identification, risk assessment, risk decision-making and control in the transportation process for the purpose of comprehensive risk control of satellite transportation work, and puts forward the viewpoint of “Reducing risk list and quantifying risk control”. The refined risk identification method proposes different control methods for different types of risks. The method designed in this paper is used in the factory transportation of satellites, and the application is in good condition, which effectively guarantees the safety of satellite transportation.
Application of adaptive square root cubature Kalman filter in turbofan engine gas path performance monitoring
Authors: Zhu Jietang , Hu Yu , Li Yin , Ming Anbo , Yang Zhengwei , Zhang Wei
Published: June 2019

Kalman filters are very popular in turbofan engine community for health monitoring purposes. In this study, in order to get better performance in terms of filtering accuracy and noise adaptability, an Adaptive Square Root Cubature Kalman Filter (ASRCKF) was proposed to estimate health parameters of the turbofan engine gas path components. In the ASRCKF algorithm, the mean value and covariance of the engine nonlinear function were calculated by cubature rule-based numerical integration method and used as a substitute for nonlinear model in nonlinear Kalman filter. The latest information of measurement parameters in the recursion and filtering process was used to estimate and self-adjust the noises cross-covariance by removable window method to get higher filtering accuracy. Compared with the Extended Kalman Filter (EKF) and Square Root Cubature Kalman Filter (SRCKF), the simulation results in the gradual and rapid deterioration process of turbofan engine gas path components indicate that the higher accuracy and faster convergence can be obtained through ASRUKF, which can be used in health parameters estimation and condition monitoring of turbofan engine gas path.1
The Influence of Polynomial Order in Logistic Regression on Decision Boundary
Authors: Wan Xing
Published: June 2019

In machine learning problems, polynomial logistic regression algorithms are often used to classify data. Compared to linear regression, polynomial regression can not only deal with linear problems, but also deal with nonlinear problems. In the polynomial logistic regression algorithm, the polynomial order has a certain influence on the classification effect. This paper studies the influence of the polynomial order on the binary decision boundary in binary classification problem. By choosing different parameter values, an approximate optimal solution can be found.
Analysis of Running Stability and Tire Wear of Monorail Vehicles
Authors: Chong LU , Dong Bo , Cao Yu
Published: June 2019

Based on the movement state of straddle-type monorail vehicle and the force state of wheels, the theoretical model is established, and the dynamic simulation software is used to analyze the anti-overturning stability of guide wheels and stabilizer wheels of straddle-type monorail vehicle under pre-pressure. Three layout schemes of guide wheels and stabilizer wheels are established, and the motion state of straddle-type monorail vehicle under three schemes is compared and analyzed. It is found that the motion state of monorail vehicle is mainly limited by the rolling stiffness and the shaking head stiffness of the vehicle itself. By increasing the rolling stiffness, the roll angle of the vehicle can be reduced, so as to reduce the load variation and speed difference of the running wheels and reduce the wear of the running wheels. Over-increasing the shaking head stiffness can reduce the side slip angle of the running wheels, so as to reduce the side slip of the running wheels and reduce the wear of running wheels.
Design & Development of Soundable CYO
Authors: Zhan Jianbo , Zheng Han , Wang Hao , Xie Jiao , Yu Tingting , Yue Baoshan , Wang Xu , Li Geng , Yu Zhenhua , Zhang Ying , Wang Tao , Yu Jiang , Li Liwei
Published: June 2019

In order to increase the interest of cigarette smoking, enrich consumers’ consumption experience, realize the satisfaction of hearing in the process of cigarette combustion, and meet the needs of some consumers who have little warning effect on hearing sound, a sound-producing CYO component was designed and produced, which uses the sound-producing device to be installed between the upper cover and the lower cover of the connector, so that the sound-producing mode of the connector adopts pure mechanical structure to achieve. The physical parameters of the splicer are calculated by ANSYS software, and the connecting effect is simulated. The CYO cigarettes connected by the connector are verified. The results show that the connector achieves the sticky effect and the tightness similar to the conventional cigarettes. There is no significant difference between smoking evaluation and smoke detection with conventional cigarettes, thus the ideal design effect is achieved.
Line of Sight Based Visibility Acceleration Method
Authors: Yao Yongqiang , Chen Yaojie , Tang Wenjun
Published: June 2019

Real-time fast display of 3D scenes is the basic content of visual simulation and one of the core links. The object-oriented quadtree is used to organize the scene. This method saves the object information with leaf nodes, which can reduce the storage capacity and processing time of the tree and reduce the management burden of the system scene. For the visual cropping acceleration problem, it is proposed based on the line of sight. The cone partitioning cutting method can effectively improve the precision of the cutting, reduce the number of nodes participating in the cutting, and has better cutting efficiency and higher stability. The effectiveness of the method is verified by designing comparison experiments.
Performance-based design method of steel-to-concrete post-installed connection under combined action of earthquake and fire
Authors: Obambi L H D , Qun Xie
Published: June 2019

ABAQUS software was first used to study the structure behaviour of steel-to-concrete connection by post-installed anchorage under cyclic loading. Three types of embedment depth 25d, 20d and 15d were considered. Based on previous simulation results of earthquake and fire, it can be concluded that the seismic performance of steel-to-concrete connection by post-installed anchorage is strongly related to the rotation angle 0 of steel beam. The heat analysis results indicate that the fire resistance of post-installed connection after 2 hours exposure could meet the requirement of related codes. Based on the simulation results mentioned above, a performance-based design conception with four performance levels has been provided to guarantee structure safety under the combined action of earthquake and fire. According to the principle of performance-based methodology, rotation angle 0 of steel beam and fire resistance rating T are chosen as critical index for performance evaluation. Among the 4 levels of performance, Level 1 has the highest specification for disaster protection. To achieve the performance level 1, the thickness of fire protection layer should not be less than 45 mm, and the embedment depth should be 25d at least.
Selection of Mechanical Design Indexes for Supporting Layer Based on Sensitivity of Asphalt Content
Authors: Wang Jian , Zhuang Wei , Chen Hao , Chen Sai , Bi Yu-feng , Zhang Hong-chao
Published: June 2019

In order to optimize the mechanical design index of asphalt pavement supporting which is sensitive to asphalt content, the mechanical parameters (dynamic modulus, compressive resilience modulus, compressive strength, shear strength, splitting strength and failure strain) of AC-20 mixture are selected as the research object, and the changes of these parameters with asphalt content are analyzed. The sensitivity of each parameter to asphalt consumption was analyzed by one-way ANOVA. The results show that the dynamic modulus and failure strain of asphalt mixture increase first and then decrease regularly with the increase of asphalt content, and the change of dynamic modulus is independent of loading frequency. However, the change of compressive strength, resilient modulus, shear strength and splitting strength is not significant with the increase of asphalt content. Dynamic modulus is most responsive to asphalt content under different asphalt types and gradations. Hence, it is suggested that dynamic modulus should be considered as the mechanical design index of load-bearing of asphalt pavement.
Finite Element Study on Shear Performances of In-filled Bolt Joint of Assembled GRC Wall with Light Steel Skeleton Frame
Authors: Tang Zhirong , Zha Xiaoxiong , Wang Baolin
Published: June 2019

A new in-filled wall is used in assembled steel structure buildings, which consists of two layers of glass fiber reinforced concrete (GRC) panels and a built-in light steel skeleton frame. To make this new wall fill in the main steel structure, a new in-filled bolt joint is used. In order to obtain the mechanical properties and failure modes under shear load, the shear performances of this joint were studied with the finite element (FE) software ABAQUS. The results show that before reaching the fracture failure strain, the in-filled bolt joint shows good elastic-plastic behaviour. When the strain of the in-filled bolt joint reaches the failure strain, the shear load reaches the peak value. Subsequently, due to the shear fracture of the bolt, the shear load drops rapidly. Throughout the loading process, the stress of steel beam and rectangular steel tube is always very small and the stress of the joint yields in a large area in the later stage.
A Prediction Model of Tunnel Surrounding Rock Deformation Based on Induced Ordered Weighted Averaging Theory and its Application
Authors: Fan Fangfang , Jian LI
Published: June 2019

For the different prediction accuracy of tunnel surrounding rock deformation prediction model are different. Based on induced ordered weighted averaging theory(IOWA), IOWA modified combined forecasting model of tunnel surrounding rock deformation has been put forward with the relationship between the accuracy and the weight of a single prediction model. With the monitoring data of Mila Mountain tunnel of highways from Lasa to Linzhi, coupling the time series prediction model of deformation and exponential smoothing model of two kinds of single tunnel, IOWA modified combination prediction model for tunnel surrounding rock deformation has been built up. The result shows that predicted displacement of IOWA modified combination prediction model for tunnel surrounding rock deformation is closer to the measured value and has higher accuracy. The combined model for the prediction of tunnel surrounding rock deformation is feasible.
Study on Effect of Late Tunnels on Deformation of Early Tunnel in Three Small Net Distance Tunnels
Authors: Jiao Ping , Ma Liang , Wu Yongzhen , Liu Yan
Published: June 2019

This paper is based on the tunnels construction in small net distance in Jinan Rail Transit Line R3. The deformation of early mining tunnel when double-line shield tunneling under different net distance conditions is simulated. The results show that the late shield tunneling will cause the clearance convergence, vault settlement and inverted arch uplift of the early mining tunnel to further deformation. When the distance is 0.8 times of the tunnel diameter, reinforcement measures are needed.
Numerical Study on Dynamic Buckling of Composite Bar with One Edge Simply Supported and Opposite Edge Clamped
Authors: Liu Chao , Yang Qiang , Han Zhijun
Published: June 2019

Considering the stress wave effect, the dynamic buckling problem of a composite rod with one side fixed on one side being axially impacted by a rigid mass is studied. Based on the Hamilton principle and the axial inertia and rotational inertia, the dynamic buckling control equation is derived. For the dimensionless, the central differential method is used to solve the governing equation. The buckling mode of the composite bar with different initial deflections under different impact mass, impact velocity, critical length and layup mode is obtained by B-R criterion. The results show that the impact velocity, impact mass, critical length and layup mode have an effect on the dynamic buckling of composite rods, and the initial deflection changes have a significant effect on the buckling mode.
Research on the Aerodynamic Characteristics of Vehicle Passing out Tunnel
Authors: Wang Gui-hua , Zhou Ji-guo
Published: June 2019

Taking bus driving out of the tunnel as the research background, study the aerodynamic characteristics of the vehicle when the vehicles subjected the sudden change wind load. Numerical wind tunnel model is established. Respectively analysis the vehicle’s aerodynamic change rule of three-component coefficients in the process of vehicle driving out tunnel at different speed under wind load and without wind load. The results show the vehicle’s aerodynamic force increases suddenly when the vehicle run out of the tunnel. The suddenly increasing pressure on vehicle is very adverse impact on the driver’s operation and driving safety.
Creep Fibre Method of Simply-supported Composite Beams
Authors: Zhang Shengping , Chen Xu , Wang Fengxian
Published: June 2019

Creep effects of composite beams can not be neglected in service-time. Creep Fiber method is used to obtain the time-depedent results, which proved to be quiet effect in both elastic and visco-elastic analysis. Only two individual centrical loading points or bars need considering, and then the system of two sumultaneous differential equations becomes simple in a clear fashion. It can be solved analyically by Rüsch constitutive equation of creep. For high and large beams of bridge structures the fibres of the two points are constant over time because the radius of inertial of steel beam is far larger than that of concrete slab, which simplifies the procedure further. The results show that under sustained loading creep of concrete produces significant negative effects. It may increase the modular ratio to 2.3 times of the initial, reduce the whole flexural stiffness by 76%, and cause the local buckling risk of the top flange and web of steel beam. These should be considered in the design of structure.
Experimental Study on Seismic Performance of Prefabricated Joints of Underground Utility Tunnel
Authors: Hu Yaoxing , Li Zhengying , He Jijun , Huang Zulin
Published: June 2019

In order to study the seismic performance of underground utility tunnel prefabricated joints anchored by button-head reinforcement, pseudo-static tests were carried out on two full-scale underground utility tunnel prefabricated joint specimens. The failure mode, bearing capacity, energy dissipation, and other seismic performance of the joints were analyzed. The results show that the bearing capacity, energy dissipation and other seismic performance parameter of these specimens can meet the seismic design requirements. However, the damage in the core area of the joint is severe under the pseudo-static loading. Therefore, when the button-head reinforcement is applied to practical engineering, necessary reinforcement measures should be taken to ensure that the joint has good seismic performance.
Test Design and Finite Element Analysis of Shaking Table of Concrete Frame Structure Reinforced with CFRP Bars
Authors: Wang Jianyue , Xu Xinsheng
Published: June 2019

The shaking table test is an irreversible process for a nonlinear model structure. Therefore, how to choose ground motion and determine the input sequence are particularly important for the success of the shaking table test. In this paper, a 1/4 scale CFRP reinforced concrete frame structure specimen model is designed and made according to the similarity theory. By using the finite element analysis software SAP2000, the finite element model of CFRP reinforced concrete frame specimen is established. Four seismic waves are selected in the simulated shaking table test process, and the dynamic time history analysis of a total of 52 working conditions is carried out, including unidirectional, bidirectional and three-directional ground motion input, and the acceleration and displacement response of the structure are obtained. Taking story drift ratio as the evaluation index, the seismic performance of the structure is evaluated. This paper provides theoretical guidance for the subsequent shaking table test.
Finite Element Analysis and Influence Factors of Flexural Behavior of HFRP Reinforced Concrete Beams
Authors: Yang Shuai , Xu Xinsheng
Published: June 2019

HFRP (Hybrid Fiber Reinforced Plastics) ribs are a new type of composite rib made of a mixture of two or more continuous reinforcing fibers. Since the HFRP ribs have a "pseudo-yield" phase similar to that of steel bars, the mechanical properties of HFRP reinforced concrete structures are quite different from those of single FRP reinforced concrete, and should be studied in depth. In this paper, the finite element analysis of the hybrid effect of HFRP bars and the flexural behaviour of HFRP reinforced concrete beams is carried out. The ANSYS finite element analysis software is used to simulate the bending test of carbon/glass HFRP reinforced concrete beams with three different hybrid ratios. The calculation results are compared with the experimental results, and the rationality of the finite element model is verified. On this basis, the influence of mixing ratio, reinforcement ratio and concrete strength on the deflection of concrete beams is further analysed.
Finite Element Analysis of Dynamic Behavior of CFRP Reinforced Concrete Frame
Authors: Zhang Haoyu , Xu Xinsheng
Published: June 2019

At present, the research on the performance of CFRP reinforced concrete structures at home and abroad mainly focuses on the ductility of individual members, especially FRP reinforced beams and columns, while the research on the ductility and seismic performance of FRP reinforced concrete frame structures is relatively less. Firstly, the finite element model of the shaking table test scale model of CFRP reinforced concrete frame structure is established by using SAP2000 finite element analysis software. Then, the non-linear dynamic time-history load condition is defined for the model, and the dynamic elastic-plastic time-history analysis is carried out to obtain the acceleration response and displacement response of the model under different levels of earthquake. The results show that the CFRP reinforced concrete frame structure is damaged and its stiffness deteriorates seriously. The lateral deformation of the structure is mainly caused by the bending deformation of the beam and column, while the lateral displacement of the column caused by the axial deformation is relatively small.
Comparison and Selection of Reinforcement Schemes for Shield Tunnelling Close Crossing High-speed Railway Viaduct Group
Authors: Wu Bo , Zhang Ziyi , Huang Wei
Published: June 2019

Numerical simulation is carried out of the group pile foundation project of the shield tunnel on Nanjing metro airport line which crossing Beijing-Shanghai high-speed railway. The paper analysed the characteristics of the horizontal displacement along bridge of the pile foundation during the whole crossing process. On this basis, the reinforcement effects of grouting reinforcement, longitudinal beam and cross bracing reinforcement, bored cast-in-place pile reinforcement are comparative analysed with the horizontal displacement alone bridge of pile as the evaluation index. Also, the feasible program of the shelter pile reinforcement could be determined by combing with the construction process and conditions.
Laboratory Tests for the Consolidation Property of Dredger Fill in the Shenzhen Area
Authors: Zheng Airong , LI Dongjun
Published: June 2019

In order to analyze the special engineering properties of the super soft dredger fill, experimental studies had been done on the physical-mechanical properties of that in Shenzhen, especially for its consolidation properties. The test results indicated that the super soft dredger fill had the properties of high water content, high void ratio and high clay content; When the confining pressure applied to the sample was less than 200kPa, the change of deformation and void ratio of it was more obvious; When the confining pressure applied to the sample was less than 80kPa, the chang of permeability coefficient of that was more significant.
Multi-objective Optimization Configuration of Capacitor Blocking Devices based on Field-Circuit Coupled Model and Improved Differential Evolution Algorithm
Authors: Zeng Wenhui , Ren Hao , Tang Yang , Ni Jiang , Chen Xin
Published: June 2019

The dc current of grounding pole will invade the transformer windings nearby when the HVDC system is in ground return operation, which will cause DC bias and affect the safety and stability of the system. It is an effective method to restrain dc current in transformer to install capacitor blocking devices at transformer neutral wire, but it is shown that this may increase the bias current of nearby transformers. For this reason, the installation of blocking device in a certain area can be considered as an optimization problem. An improved differential evolution algorithm is proposed to optimize the multi-objective configuration of capacitor blocking devices to suppress DC bias globally. The field-circuit coupled model is established to solve the potential. The objective function is to minimize the number of installations of the devices and the absolute sum of the total DC current of the transformer in the region, and the constraint is all DC current at the neutral point of each transformer is under the limit, then the optimal configuration model is established. Finally, the chaos mapping theory, adaptive parameters and elitism preservation strategy are introduced into the difference evolution algorithm to solve the model and obtain the optimal allocation scheme.
Design and Implementation of an Intelligent Decision-making System for Power Grid Planning
Authors: Jia Chunrong , Wang Zhou , Fu Bingbin , Shi Yi
Published: June 2019

In order to effectively cope with the situation of large amount of data, complex decision-making and lack of technical means in power grid planning, an intelligent assistant decision-making system for power grid planning based on platform design, visualization and advanced decision support function is designed and implemented. The system is closely integrated with Geographic Information System (GIS) and embedded in an integrated database. It has the functions of adaptability evaluation, investment priority decision-making, power grid reconfiguration scheme analysis and data interface of power grid simulation software. In the process of assistant decision-making, the coordinated evaluation of power supply and power grid is realized by the simulation of power grid dispatch, the investment priority of the project is determined by imitating the principle of static security analysis, the backbone network of power grid is identified by graph theory algorithm, and the data of the planning scheme is extracted from the newly developed simulation software data interface to reconstruct the topology and initialize the data of model.
Research on the Index System of Economic Activity Analysis under Electricity Reform
Authors: Du Yi , Lin Hongyang , Xiang Kangli , Li Yuanfei , Lin Changyong
Published: June 2019

To take the initiative to adapt to the electric power system reform and steadily improve operating benefit, the State Grid Fujian Electric Power Company clarifies the impact of the electricity reform policy on the corporation’s operational activities, actively explores the index system of economic activity analysis under the influence of the new electric power reform environment, quantifies the impact of the power grid reform on the corporation’s production and operation, timely affirms achievements, reveals problems, improves internal management, increases efficiency, and assists the operational decision-making.
Research and design of wind power grid switch for low voltage crossing ability
Authors: Zhang Liu , Ma Shaohua , Gu Cailian , Zou Quanping
Published: June 2019

This paper proposes a new type of wind power grid switch design, according to the requirements of the wind power generation system for grid switch technology, combined with the electromagnetism theory and empirical formula. The new interconnection switching used the characteristics of the high remanence of two-phase magnetic materials to solve the problem such as great power consumption, holding not across low voltage, in view of the traditional electromagnetic grid switch, and then set up new interconnection switching of the three-dimensional entity model, finally used the finite element simulation software, the change of the curve, such as the electromagnetic suction parameters and contact motion speed was obtained, the relationship between the structure parameters and interconnection switch operating characteristics of the contact was also obtained. Finally simulation experiment results show that the new grid switch in the case of no excitation current keeps off state, which can be well applied to wind power generation system, and can effectively improve the stability of large-scale distributed power grid operation, and has a certain theoretical significance and practical value.
The study of NinH(n=1-6) clusters by density functional theory
Authors: Zhang Xiaozhen , Wen Junqing , Bai Liang
Published: June 2019

In this paper, the geometric structures and local relative stability of NinH(n= 1-6) have been systematically calculated using the generalized gradient approximation (GGA) under density functional theory. The studied results indicate that adding an H atom to the Ninclusters does not significantly change the basic structures of Nin, and the most stable structures can be received by adsorbing an H atom on the side of pure Ninclusters. The binding energy of each atom of Ninand NinH show same variation trend, the values of NinH are larger than that of Nin. The fragmentation energy, adsorption energy and HOMO-LUMO gaps don’t show obvious oscillation behavior with cluster size evolution, but the values are larger at Ni6H, which illustrate that the corresponding cluster has high stability and low chemical activity.
Synthesis of spherical Ni0.8Co0.1Mn0.1(OH)2 precursor via hydrothermal method assisted by microfluidics
Authors: Liu Ming-Yue , Tan Jing , Deng Wen-Sheng , Su Yue-Feng , Chen Lai , Liu La
Published: June 2019

Nickel-rich materials have been considered as promising cathode candidates for Li-ion batteries. In this work, the spherical Ni0.8Co0.1Mn0.1(OH)2 precursor with good crystalline is synthesized via a hydrothermal method assisted with microfluidics. The effects of (NH4)2CO3 aqueous solution addition ratio and hydrothermal time on the formation of precursors are investigated comprehensively. The as-obtained precursors after optimization (hydrothermal time of 24 h and the concentration of the (NH4)2CO3 is 0.3 mol/L) display the spherical microstructure with homogenously distribution morphology, which can be clearly observed by scanning electron microscope. This work provides a rational route to controllably prepare the spherical Ni0.8Co0.1Mn0.1(OH)2 precursors.
Investigation of the Effect of Boundary Condition on the Property of TRIP Steel by Finite Element Simulation
Authors: Li J.H. , Deng H.P. , Yu S.
Published: June 2019

TRIP (Transformation induced plasticity) steel combined high strength and high plasticity perfectly, which depend on the micro structure of the material greatly. Residual austenite plays an important role on the micro material transformation and macro property. Different boundary condition makes different stress and strain field of the TRIP steel and induced different residual austenite transformation. Under different compression stress, the residual austenite transformation was different, to predict the micro transformation behavior, investigation of the macro stress character was necessary. Finite element simulation was carried out in this paper to investigate the stress filed of TRIP steel under different boundary condition to predict the micro residual austenite transformation and macro property development.
An Electronic Control Air Suspension System for Commercial Vehicles
Authors: Tan Xiaoyan , HU Jiansheng , Dong Guisheng , Chen Bo
Published: June 2019

At present, the developed countries will air suspension applications in medium and heavy trucks and trailers on the penetration rate of more than 90%. In contrast, due to the influence of commercial vehicle production technology, the utilization rate of air suspension in commercial vehicles is relatively low. The proportion of air suspension used in heavy trucks and trailers is only 5% - 10%.With the rapid development of China’s economy, people’s demand for cars is also getting higher and higher, not only a means of transport, but also on the ride comfort, ride comfort requirements are also getting higher and higher. Foreign advanced electronic control air suspension is also becoming more and more popular, which will inevitably lead to the domestic market demand for electrically controlled air suspension. The author of this article during the Ruian Ruili group Beijing Great Automotive Components Company Limited, the electronically controlled air suspension hardware localization, has made some achievementsand some suggestions.
Electron irradiation effects on the mechanical properties of polyethylene
Authors: Liu Yuming , Yang Xiaoning , Zhao Chunqing , Wang Jinghu
Published: June 2019

Studies on space electron radiation effect for evaluating property degradation of space materials are one of the important things for exposing the faults of the materials in orbit. Here the influence of electron flux and energy on the electron irradiation effect of polyethylene that is one of the common materials in spacecraft has been studied. Due to the analysis results of SEM and FTIR, it is proposed that the irradiation damage mechanism of the materials is independent of electron flux and electron energy. The molecular structural modifications and chemical changes of the materials have all occurred after each electron irradiation test. But the degree of damage on the mechanical properties of polyethylene during the electron irradiation test is dependent on electron energy. The mechanical properties of polyethylene will completely be lost after electron irradiation when the energy of electron is above 1 MeV, and the polyethylene will be broken down.
Research on Damping Mode of Passenger Vehicle Air Suspension System
Authors: Chen Bo , Dong Guisheng , Shi Yantao , Tan Xiao Yan
Published: June 2019

With the continuous development of economy in China, the demand of both passenger car volume and its comfort increases.The air suspension system has solved the comfort problem as the times require. At the same time, the reliability of the product has attracted more and more attention from users. This study describes the structure and design principle of the air suspension system, and makes an analysis and Discussion on the key use effect, i. e. the damping effect.
Experiment Study on the Vibration Characteristics of inner Journal of Sliding Bearing
Authors: Wei S H , Lu W X , Wang M H
Published: June 2019

Sliding bearings are widely used in various types of rotating machinery due to the development of modern industry. The oil film pressure produced by the sliding bearing has very strong nonlinear characteristics. In order to study the dynamic characteristics of sliding bearing in experiments, in this paper, a sliding bearing test rig is restructured. A special acquisition system is designed to measure the vibration of the journal in sliding bearing. The acquisition system consists of optical fiber displacement sensors, pre-processor, data acquisition device, host computer. Several experiments were carried out by the test rig under different rotational speeds, different eccentric masses, and different bearing loads. The effects of the rotational speed, eccentric mass and bearing load on the dynamic characteristics are analyzed and some conclusions are obtained which is consistent with the theory.
Application of SA-PSO Algorithm in Parameter Optimization of Dynamic Vibration Absorber
Authors: Zhe-ming Chen , Peng Wang , Jiang-hua Fu , Bao Chen
Published: June 2019

Focus on the noise problem in a 7-segment midsize SUV in the condition of wide open throttle in gear 2, noise testing and finite element analysis were combined to analyze the problem, and it was found that there was a significant resonance band around the frequency of 214 Hz, which was particularly evident under the fourth-order excitation. The frequency of resonance band is close to the second-order modal natural frequency of the sub-frame, The resonance band needs to be eliminated to reduce the noise inside the car. Adopting the scheme of installing a dynamic vibration absorber on the sub-frame to make the second-order modal of the sub-frame avoids the resonance frequency. The simulated annealing algorithm is combined with the particle swarm optimization algorithm to optimize the parameters of the dynamic vibration absorber. A dynamic vibration absorber was designed with optimized parameters and verified by simulation and installed on the car. It was verified that The designed dynamic vibration absorber eliminates the 214Hz resonance band and obviously reduce the noise inside the car.
Study on the seismic performance of fuxi miao’s congenital temple
Authors: Xin Wang , Zhao-bo Meng
Published: June 2019

In order to study the seismic performance of fuxi miao’s congenital temple in Tianshui, we establish 3-D finite element model of the congenital temple in this paper. In the term of frequent earthquake and rare earthquake, Lanzhou wave and El-Centro wave and Taft wave are adopted to analyze the seismic response. It is shown the displacement reaction of the roof is largest, followed by Taft wave, and Lanzhou wave is smallest under El-Centro wave; The acceleration reaction of the roof is largest, followed by El-Centro wave, and Lanzhou wave is smallest under Taft wave. The displacement and acceleration maximum of the roof are slightly greater than that of the second floor, but are much greater than that of the first floor, thus the seismic response of the roof is the strongest. The acceleration peak of the nodes from the top of the first floor column to the roof increases very little, therefore it indicates the column base’s isolation and the friction energy dissipation of the mortise and tenon joint of beam and column make the congenital temple have good performance and shock absorption.
A Quantitatively Comparative Study on Green Pattern of Urban Park in Beijing, London, Paris and New York Using Spatial Statistics Model
Authors: Xin Yang , Rui Liu , MeiTing Su
Published: June 2019

This paper comparatively analyzed green pattern content of Beijing, London and Paris, New York with three spatial statistical models: average nearest neighbor analysis method, weighted standard deviation ellipse method and kernel density method to achieve scientific and accurate data analysis. The paper analyzed aggregation level and distribution of urban parks, area distribution of urban parks and green pattern overall model analysis of four cities. Finally, three analysis methods of spatial statistical models provided new ideas for research on urban green space pattern and effectively realized scientific and refined research of green pattern.
Bearing capacity analysis and field test of multi-layer formwork support system for high-rise buildings
Authors: Xiahui Hao
Published: June 2019

The multi-layer reinforced concrete formwork support system is a comprehensive structural system considering the formwork, structural beam and steel plate and steel pipe support. The demolition and turnover of the formwork support are affected by the time-varying of the concrete structure and the randomness of the construction. In this paper, the multi-layer formwork support system of the 2# building project of a real estate development project is field tested, and the multi-layer formwork support system is obtained during the construction process. The time-course curve of the axial force of the rod and the concrete strength growth curve are analyzed. The force transmission mechanism and load transfer law of the multi-layer formwork support system are analyzed.
Temperature effect analysis of pre-tension and deformation characteristics of planar membrane structure
Authors: Yanmin Li , Shuqi Qin
Published: June 2019

In this paper, the planar membrane structure of an engineering example is analysed theoretically from the variation of pre-tension and membrane surface deformation with temperature. Then ANSYS software is used to analyse the pre-tension changes of the membrane structure and the membrane surface deformation with the uniform load under different temperatures (-50∼70 °C) for the membrane structure. The trend image of pre-tension and membrane surface deformation with temperature was obtained, and the minimum value of pre-tension of the membrane structure was obtained according to the relevant regulations. According to the variation law of pre-tension, the pre-tension selection scheme for the installation of planar membrane structure is summarized, which provides some references for the determination of pre-tension in the installation of planar membrane structure.
Teaching reform of foundation engineering in applied universities based on emerging engineering education
Authors: Zhong-jin WANG , A-jin LI , Jin-zhu LI , Peng-fei FANG
Published: June 2019

Foundation engineering is an important professional course in the undergraduate course system of civil engineering major. Compared with other civil engineering major courses, the course of foundation engineering has its particularity, and the reform of this course is also of great significance. Based on emerging engineering education, the reform for teaching and practice of foundation engineering course in civil engineering major of Applied University is discussed. Some suggestions are proposed on the reform of traditional teaching contents, the setting of courses and the construction of practice bases. The evaluation system of teaching quality is also proposed in this paper.
Problems in Bridge Health Monitoring and Application of Intelligent Monitoring Technology
Authors: Ji Xuan , Yang Zhuo , Huang Xiaodan , Tan Lingsheng
Published: June 2019

In view of the current research status of bridge health monitoring system at home and abroad, this paper summarizes the problems existing in bridge health monitoring research and discusses the solutions to these existing problems. On this basis, it also puts forward the advantages and development trends of intelligent health monitoring. Besides, taking the intelligent monitoring of Haiyin Bridge as an example, the modern network technologies such as intelligent collector, networking and cloud platform were adopted to realize the functions of real-time bridge monitoring, intelligent analysis, and safe type-warning. Thus, a complete set of visualized management system for bridge intelligent health monitoring information is finally formed. This shall provide references for the intelligent development of bridge health monitoring
Construction and structure analysis of Yongshun Bridge in Lichuan
Authors: Zhu Fawen , Zhou Jianfeng , Zhu Tianyi , Li Baofeng
Published: June 2019

Lichuan YongShun Bridge is the only wooden arch lounge bridge, which composites stretching timber beam and inverted v-shaped brace, in Wuling Mountain. This paper introduces the basic situation of YongShun Bridge, analyzes the relationship between its special construction and structure. Through establishing the finite element model and simulating the stress and displacement of the bridge under the action of dead load and live load, the paper summarizes the main mechanical behavior of the bridge and the influence of special construction on the bridge structure.The research results have certain guiding value for the protection and maintenance of the bridge and the construction of modern wooden structure bridge.
Research of Place-keeping in Urban Wetland Park Management
Authors: Wu Mei , He Dan
Published: June 2019

In recent years, urban wetland parks have gone through a rapid development. More and more authorities, public and researchers have focused on urban wetland parks. But most attention is put on the design and planning, conservation and long-term management of urban wetland parks that have not received enough attention in many cities in China. This study takes Chengdu Bailuwan Ecological Wetland Park as a case study to analyse place-keeping and explore what extent place-keeping happens in Chinese urban wetland parks.
Research on the Measurement of Agricultural Green Development Level in Qinghai Province
Authors: Haijing Ren , Yafei Liu , Shengxi Ding
Published: June 2019

By constructing the evaluation index system of agricultural and green development level in Qinghai Province, using the entropy weight grey correlatuion topsis model and obstacle degree model, we calculated on the agricultural green development level during second national agricultural survey to the third national agricultural survey and analyzed the level in the view of the time and space.The analysis of the level of agricultural green development in Qinghai Province is based on two aspects—time and space. The results show that the level of agricultural green development in Qinghai Province has rose with fluctuation, but it has not yet broken through the intermediate level. In view of this, this paper proposes countermeasures such as optimizing the structure of agricultural industry, strengtheningthe construction of talents and infrastructure, and promoting the implementation and supervision of ecological agriculture.
Practical Problem and Reform Path of the Departure Audit of Natural Resources Assets: Based on China’s Practice
Authors: Fengyan Wang
Published: June 2019

With the continuous practice of the concept of sustainable development by the Chinese Government, the protection of natural resources and the optimization of the ecological environment have received unprecedented attention in China at present. In order to further speed up the construction of ecological civilization and promote the sustainable development of resources, the Chinese government has begun to implement the departure audit of natural resource assets, and has strengthened environmental protection and resource management. This paper analyses the practical problems existing in the practice of the departure audit of natural resource assets at the present stage, systematically dissects its causes, and puts forward its reform path.