Table of contents

2019 5th International Conference on Mechanical Engineering and Automation Science (ICMEAS 2019) was held in China University of Geosciences (Wuhan), Wuhan, China during Oct. 10-12, 2019. ICMEAS 2019 was Co-organized by China University of Geosciences (Wuhan) and Hong Kong Society of Mechanical Engineers (HKSME). The conference provides a useful and wide platform both for display the latest research and for exchange of research results and thoughts in Mechanical Engineering and Automation Science and other topics. The participants of the conference were from almost every part of the world, with background of either academia or industry, even well-known enterprise. The success and prosperity of the conference is reflected high level of the papers received.

The proceedings are a compilation of the accepted papers and represent an interesting outcome of the conference. This book covers 4 chapters: Manufacturing Engineering; Materials Engineering; Mechanical Engineering; Design Engineering.

We would like to acknowledge all of those who supported ICMEAS 2019. Each individual and institutional help were very important for the success of this conference. Especially we would like to thank the organizing committee for their valuable advices in the organization and helpful peer review of the papers.

We sincerely hope that ICMEAS 2019 will be a forum for excellent discussions that will put forward new ideas and promote collaborative researches. We are sure that the proceedings will serve as an important research source of references and the knowledge, which will lead to not only scientific and engineering progress but also other new products and processes.

Prof. Huafeng Ding, China University of Geosciences (Wuhan),China

Prof. Ian McAndrew, Capitol Technology University, USA.

List of Conference Committee Co-chairs, Program Committee, Local Committee, Advisory Commitees, International Technical Committee are available in the pdf.

All papers published in this volume of IOP Conference Series: Materials Science and Engineering have been peer reviewed through processes administered by the proceedings Editors. Reviews were conducted by expert referees to the professional and scientific standards expected of a proceedings journal published by IOP Publishing.

Road detection technology has been widely used in many fields, such as vehicle's assisted driving, robot autonomous navigation, military defense, public security and so on. In this paper, the road detection method based on sensitive region pixel sequence (SRPS) solution is studied. Firstly, the recent advances of the road detection method based on machine vision are summarized. Secondly, analyses the principle of road detection technology based on sensitive region pixel sequence (SRPS) solution to improve road detection efficiency and accuracy of the vision method. Finally, experimental results show that the sensitive region pixel sequence (SRPS) solution has an important significance to reduce the calculation cost of the robot's road detection system.

In the injection molding cycle, the cooling time consumes more than 70% of the molding process, optimizing the molding cycle time can be done through the selection and the design of appropriate cooling system that will be able to achieve equal distribution of the temperature along the part and quickly dissipate the heat. This paper presents an analytic study on the simulation of cool + fill + pack + warp in Autodesk Moldflow 2012 for the automobile headlamp shell, the simulation is made on of four different cooling systems, after comparison of the obtained results, the Spiral Zigzag Conformal Cooling Channel (SZCC) has the lowest time required for the part to reach the ejection temperature, with 61.22 seconds, it also shows an improvement on the volumetric shrinkage with the part's deflexion that have been reduced from 2.15 mm on the first design to 2.12 mm, making Spiral Zigzag Conformal cooling the best solution for this model.

Achieving effective service time in restaurants hinges on implementing and integrating innovation in design and technology. A combination of restaurant layout configuration and conveyor belt system integration is proposed to enhance the turnaround service time performance. Emphasis on the layout reconfiguration with optimized dining capacity and conveyor system for semi-automated function are applied to existing restaurants by heuristic method. Then operation is simulated by agent-based approach in Anylogic simulator. Results yielded an improved in the total turnaround service time by 2.75% to 5%, which correspond to an approximate 78% reduction on a food-to-table service time. The enhanced performance shows the effectiveness of reconfigured layout to service more customers without compromising delivery time. While conveyor belt mechanism provides the greatest food delivery time and manpower reduction, with a considerable payback period of 6 months. The findings and modelling will aid the implementation of semi-automated restaurant as a stepping stone to one fully automated.

Medical hazardous chemicals storage system is a special storage system. Its management basically relies on getting rid of a lot of manpower and increasing the safety and reliability of management. Using information management is a necessary way to improve storage efficiency, reduce storage cost and improve storage security. This design adopts wireless sensor network technology according to the characteristics of storage system of medical dangerous chemicals (Wireless Sensor Networks, WSNs). The wireless sensor network node design scheme is proposed. Based on IEEE802.15.4/ZigBee protocol, the wireless sensor network node is designed and implemented by PIC18F4620 single chip microcomputer and wireless radio frequency chip CC2420. Realize low cost to improve the security and real-time of monitoring, realize information sharing and network remote monitoring.

The infusion service robot was taken as the research object, and the algorithm of path planning for infusion service robot was simulated by the sensor network system in this experiment. The ant colony algorithm was selected based on the sensor network node optimization deployment of the mobile service robot. Based on sensor network for hospital environmental information collection, combined with sensor network node information and RSSI algorithm based on MATLAB to achieve positioning, and then complete the simulation study of infusion service robot navigation. The ant colony algorithm was verified as the basic method and feasibility of applying the path strategy of the robot platform. During the testing process, some conditions and algorithms were simplified to avoid the complexity of the problem.

Indonesia is a country with a tropical climate that has two seasons, namely the dry season and the rainy season. In the dry season, sun drying is the most widely used method for agricultural products. In the rainy season, people who open businesses in the food processing sector have difficulty predicting uncertain weather. The community needs solar thermal energy to dry food ingredients in the form of opak, tubers, fruits, etc. In the rainy season, the value of production has decreased. This study aims to create a drying machine that can help people to dry various types of food and fruit products. The research was carried out in several stages, namely field observation, literature study, design, manufacturing, and performance testing. The study states that: (1) the manufacturing process of electrical machine dryer was done in three stages: the initial stage, advanced stage, and the final stage. (2) the trial of an electrical dryer machine was used to dry opak and banana. Data obtained in the form of opak before drying weighs 3.4 ounces and after drying to 2.2 ounces. Whereas the banana before drying weighs 7.3 ounces and after drying to 4.5 ounces; (3) electrical dryer machine is very helpful in the process of drying food processed products in Subang Regency. Keywords: manufacturing, electrical dryer machine, opak and banana.

This paper researched the application of non-mold casting technology for reducing the development cycle and cost of tractor diesel engine cylinder body. The detail of the each process method has explained which based on the non-mold casting process of a diesel engine cylinder block. The results showed that rapid casting of diesel engine cylinder block can be realized by the non-mold casting composite forming technology, combined with CAD/CAE technology and virtual reality technology. The advantages of this method have fast speed, low cost, green, and lightweight, that is to say, piece manufacturing cycle was shortened by more than 50%, single piece manufacturing cost was reduced by more than 81%, and 8-9 molds were saved.

Aiming at solving the robotic grinding problem of aircraft engine blades with complex surface, this paper proposed an adaptive force control method using fuzzy PID algorithm, which can ensure that blade surface is completely polished to eliminate residual texture and harmful stress concentration. First, an intelligent digital compliant grinder with active and passive compliance was developed. Second, a fuzzy PID adaptive algorithm was proposed, which can stabilize the contact force between the grinder and the blade. Third, a protection scheme was proposed to prevent excessive grinding. In the polishing process, the robot arm was fitted with the blade. According to the surface profile of the blade, the robot arm moved in a specific trajectory, keeping the blade in contact with the grinder. During grinding, some parameters, such as the abrasive belt velocity, the abrasive belt type and contact force, could affect the quality of the grinding process. Therefore, appropriate parameters were selected. The experimental results showed that the actual force fluctuates within 0.5N. In addition, the original surface roughness was 1.672um, which was reduced to 0.054um by adaptive force control method, comparing to 0.589 urn with the non-force control. Not only is the contact force more precisely controlled, but the grinding accuracy is greatly improved.

In order to improve the accuracy of the reliable analysis of the belt conveyor, based on the belt conveyor fault data, firstly fit the probability density distribution function of the belt conveyor fault interval time. According to the characteristics of the fault data, it is inferred that it may obey the Weibull three-parameter distribution. The Weibull distribution model is obtained by combining the least squares method with the correlation coefficient method, and the accuracy of the model is verified by d test. Finally, the reliability of the belt conveyor is analysed, and the measures to improve the reliability of the belt conveyor are given, which provides a theoretical basis for the daily maintenance of the belt conveyor.

Topology optimization (TO) has been widely used in the field of additive manufacturing (AM), but the structure designed by the density-based optimization method has obvious material gradient and complex internal structures, which are difficult to be directly manufactured with specific process. This paper proposes a multi-scale design method for designing cellular structure with topology optimization. Firstly, micro units with variable density are designed to support smooth interconnections. Then, we provide a assembling method to generate models with density distributions similar to topology optimization method, while guarantee the manufacturability of the structures. The experimental results show that the generated model does not need support in fabrication, and retains the optimized mechanical properties, which can be used as a TO based fill pattern for 3D printing.

In order to explore the motion characteristics of the third body particle in the friction of the rough braking interface, based on W-M fractal theory and elastoplastic mechanics theory, the finite element model of the three body micro-extrusion shearing process of rough contact surface is established. The influence of the braking parameters on the motion characteristics of the single-particle third body is analyzed. The analysis results show that the three body contact steady state increases with the increase of brake pressure, and the shear speed affects the three body contact vibration. An increase in the friction factor accelerates the third body discharge friction gap to exacerbate the wear condition.

SiCp/Al composites are composed of two different material properties of aluminium matrix and SiC particles. In order to deeply study the erosion process of SiC_p/Al composite in EDM, a single pulse discharge model of SiCp/Al composites was established. The melting and solidification model and the volume of fluid (VOF) model in Fluent software were used to simulate the thermal erosion process of EDM. The change of temperature field and the formation of molten pool in the heating process of SiC particles and Al matrix are analysed. The number of SiC particles in molten pool is counted and analysed, and the number of SiC particles in molten pool was counted, the simulation results were verified by the single pulse EDM experiments. The results show that the depth-diameter ratio of the molten pool increases with the increase of the pulse width, and decreases with the increase of the peak current. The number of melted particles in molten pool is basically unchanged.

The most important activities that improve the economy of Malaysia is the construction industry. Hence it will cause the usage of the concrete increase. When the concrete usage increase, it also increase the cement use because cement is the primary material that forms the concrete and during the production of the cement, it will cause the emission of carbon dioxide which will harm the environment as well as people in Malaysia. After that, alum sludge also caused a lot environment problem because it is lack of potential to be reused in other industry and it needs to be treated before it disposed of, which will cause the financial problem to the government. After the treatment, the economical ways to dispose of it is by using landfill method. But due to a limited landfill site in Malaysia and it is the temporary solution for the disposal of the waste, it becomes a problem to Malaysia and the number of the alum sludge keeping increase year by year because of the population increase year by year too. The purpose of the study is to find out the effectiveness of this combination. The research method that use in this study is by taking out some experiment such as slump test also known as workability test, compressive strength test, flexural strength test, ultrasonic pulse velocity (UPV) test (direct and semi-direct method) and scanning electron microscope (SEM) with the concrete day-age 7, 14 and 28 days. The result gets these test is the 10% alum sludge as a partial replacement for metakaolin in concrete adding superplasticizer (Sika Viscocrete 208) is the best replacement level in term of the workability compressive strength, Flexural strength, speed of the UPV and in scanning electron microscope. After 10% replacement level, the reading all suffer a downturn. Additionally, when the day-age of the concrete increase, the reading will be increase too. This happens to all the replacement level and the 10% replacement level with 28 day-age achieve the highest reading in this study. The contribution and implications of the findings are the using the 10% of the alum sludge as a partial replacement for metakaolin in concrete adding superplasticizer (Sika Viscocrete 208) is the best replacement level compare to others.

The objective of this paper is to study the cutting force and cutting temperature in turning of titanium alloy. The simulation of cutting force and cutting temperature by finite element simulation software ABAQUS is conducted. The orthogonal experiment is designed. The influence of various factors on cutting force and cutting temperature is obtained. A prediction model of cutting temperature and cutting force is obtained by performing multiple linear regression analysis on the data obtained from orthogonal experiments.

Cars with internal combustion engines using hydrocarbon fuels occupy the main market share. The cost of these products is increasing, and this negatively affects the prosperity of the population and the cost of freight transportation. The growth in energy consumption and the rapid growth of cars deplete non-renewable natural oil and gas resources, leading to intense combustion of atmospheric oxygen.

One of the promising types of environmentally friendly engine is a cryogenic fuel engine. Such engines have higher energy performance and lower cost in comparison with electric vehicles, and their operating costs are comparable with traditional cars, taking into account the ecological aspect.

The study presents the development of methods for calculating the rotor-blade engine and its design. Since refrigeration plants consume 3% of the internal combustion engine power, it is advisable to replace them with autonomous units using a cryogenic working fluid, thereby reducing emissions of harmful substances into the atmosphere.

Taking blank temperature, mould temperature and friction coefficient as test factors, the orthogonal experiment of three factors and three levels of automobile connecting rod forging was designed. Using Deform-3d, the forging experiment under different factors is simulated, and the forging results under different technological parameters were obtained. The process parameters of connecting rod forging are optimized by using the comprehensive measurement method and taking deformation uniformity and maximum forming load as indexes. The results show that the optimized process parameters can reduce the forming load and improve the deformation uniformity.

For the sake of study the pressure capability of ferrofluid seals with small sealing gap, a diverging stepped ferrofluid structure with small sealing gap was designed according to the theory of stepped ferrofluid and magnetic path design, and the length and cross-sectional area of the permanent magnet (NeFeB) are obtained. On the basis of these parameters, the ferrofluid distribution of seal gap is calculated by using the magnetic ferrofluid element method, and the pressure capability is obtained, then the reliability of the magnetic path design is obtained according to the capability of withstand voltage. There are some findings as following after analysis and comparison. It is the magnetic flux leakage at the junction of the pole boot and NeFeB that cause pressure capability calculated by the magnetic path method is lower than that calculated by the finite element method.

The purpose of this paper was to explore a suitable icing test method which can achieve the requirement of the experimental conditions better and faster in atmospheric Icing Laboratory. So, the effects of varying the spray method and spray time of different conditions were studied in experiment. The ice shape and profile of ice accretion obtained in atmospheric icing laboratory were investigated with variable air temperature. The icing object was exposed to the one aerosol cloud------freezing rain. In addition, the heat balance model of dynamic process of single droplet would be set up, the experimental condition of distance between nozzles and icing object was analysed by simulation calculation for the model. At the same time, appears the effects of different distances on the mass, ice shape and ice accreted of profile under different conditions in experiment.

With the fast developing of modern high-speed railways, it is urgent and meaningful to introduce effective design approach and theory for advanced railcar development. A design approach and theory for the hydrostatic propulsion drive system of a tamping machine is proposed in this study, the design approach and theory includes the overall design method, specification of the hydraulic pump and motor, the optimally matching of the hydraulic pump and diesel engine and the force equilibrium verification. A design case study is finally conducted and a series of good performance validates the effectiveness of the proposed design approach and theory: the designed closed-type hydrostatic propulsion drive system is smaller and more integrated in configuration, and is with high efficiency; the designed system is stable and fast in dynamic response with acceptable overshoot and errors, the displacement performance of the tamping machine is satisfactory for its cyclic tamping operations, and the tamping machine has also got a wide scope for high-speed mobility with satisfactory acceleration performance. Thus, the proposed design approach and theory in this work will be instructive for further tamping machine product development and design optimizations.

As a key structure in the process of lifting heavy objects by cantilever cranes, the boom is of great significance. When the cantilever crane carries heavy objects, the load on the boom is a typical moving load. The traditional structural optimization method cannot fully consider the influence of the moving load on the structure. Based on the variable density structure topology optimization method, the equivalent moving load method is proposed to transform the motion of heavy objects on the boom into multiple equivalent working conditions. And according to the structural characteristics and motion form of the boom, the weight coefficient of every equivalent working conditions is assigned. The number of equivalent moving loads is determined in the form of multiple growth, and finally the lightweight cantilever crane boom structure is obtained, which is 32.08% lighter than the original structure, thus verifying the structural topology based on the equivalent moving load method proposed in this paper. The feasibility and effectiveness of the optimization method are also provided for other structural optimization that are subject to moving loads.

With the good performance and wide application of surface texture in various aspects, more and more scholars are devoted to investigating the effect of texture interface on tribological properties. Disc brake friction pair is a typical friction brake interface. In order to consider the influence of grooved brake interface on vibration characteristics during braking, a simplified finite element model of brake interface is established in this paper. By processing parameterized grooves with different lengths and angles on the surface of the brake disc, the effects of "blind groove", "through groove" and "angle" on the vibration characteristics of the brake disc during braking process are simulated and studied, which can provide reference for the structural design and optimization of the brake disc texture.

The fatigue failure mode of the brake disc is the initiation and expansion of the fatigue crack on the surface of the brake disc until the brake disc brakes. Therefore, considering the fatigue failure mode of the brake disc, the fatigue life of the brake disc is calculated. Firstly, the thermo-mechanical coupling model of the brake disc and pad is established by Abaqus software, so that temperature and stress of the brake disc could be obtained. Then, the surface crack initiation life of the brake disc is calculated by fe-safe software Finally, the fatigue crack growth life of the brake disc is calculated by nCode software. The calculation and analysis results show that the fatigue crack of the brake disc appears on the outer side of the brake disc friction surface under the working condition of this paper. The crack initiation life is that the number of braking is 12830 and the crack propagation life is 695000for the number of braking.

Engine room is the place where marine power equipments, pipelines and other equipments are arranged centrally. In order to optimize the design process of engine room equipment layout, this paper proposes a method for the optimization design of engine room layout baesd on improved fuzzy comprehensive evaluation. By constructing the personnel activity space model and equipment space model, formulating the engine room environment constraint conditions dominated by personnel experience factors and obtaining the feasible scheme of engine room equipment layout. By designing the evaluation model of equipment layout plan in the engine room, formulating the evaluation method dominated by fuzzy comprehensive evaluation algorithm and obtaining the optimal layout scheme. Based on fuzzy comprehensive evaluation method, the improved method directly retains the influence of the design experience factors of personnel, which can make engine room equipment layout and pipelines more in line with engineering requirements, as well as provide better equipment accessibility and personnel accessibility.

The coupled Euler-Lagrangian method is used to simulate the load characteristics of a Twin-Float seaplane when it is landing in waves. The fluid domain is described by Euler, the structure is described by Lagrangian, and the coupling interaction between the Euler material and the Lagrangian element is simulated by the enhanced immersion boundary method. Firstly, a three-dimensional numerical wave tank is established, and the accuracy of numerical wave-making is verified by linear wave theory. Then, the numerical calculation of seaplane wave landing load at different wave heights with the same wave length is carried out, Lastly the numerical results compared with the model experiment of towing tank. The numerical simulation results are in good agreement with the model experiment results. The results show that there will be obvious bouncing phenomena when the seaplane landed in the wave, and the higher the wave height is, the greater the load will be generated when the wave length is the same.

The design of machining fixture layout optimization for near-net-shaped jet engine blade is a major problem in the blade processing and manufacturing process. In this paper, the mathematical model of machining fixture layout optimization is established, and the influence of the clamping point position on the machining deformation of the blade-fixture system is analysed. Firstly, the mathematical model of machining fixture layout optimization is established according to the process requirements and clamping characteristics. Secondly, the positioning clamp points of machining fixture is optimized by the combination of finite element analysis (FEA) and genetic algorithm under the optimization target of the minimum value of the maximum deformation of the blade. Finally, cutting experiments are carried out to verify the reliability of the optimal layout fixtures, and the feasibility of the algorithm is verified by comparing with the minimum value obtained by the traditional Monte Carlo statistical method.

The idea of using low-potential energy of cryogenic liquids has recently become more widespread. This is primarily due to the increasing production of cryogenic substances, as well as the general trend of energy saving and the energy potential existing in the cryoproduct in the form of energy previously used for its liquefaction.

Low-potential energy is the energy of a colder environment, having the same pressure as the consumer's energy converter. Currently, one of the most frequently used cryogenic substances is liquefied natural gas (LNG), and methods of regasification and use continue to improve.

This paper proposes a method for a comparative analysis of the use of liquefied natural gas as a working fluid, a study of the efficiency of the regasification process. The main parameters of energy installations were calculated and the main advantages and disadvantages were identified on the basis of the results, and the most optimal one was selected.

In this paper, we calculate the parameters of the energy complex on liquefied natural gas (LNG), which serves for the gasification of LNG with its further utilization in the circuit of a steam turbine plant, during operation of which additional electrical energy is generated. We evaluate the effectiveness of regasification of cryoproducts and evaluate the potential of using Cold Energy.

Various schemes of power plants using Cold Energy are considered. The parameters and characteristics of the combined-cycle plant consisting of the gas-turbine circuit and the steam-turbine circuit are calculated. The coefficient of cryoproduct energy return (liquefied natural gas) of the considered schemes is calculated and and based on the data obtained, the most optimal one is selected.

In this paper, the calculation and determination of the parameters of a mini-CHP on the basis of a heat pump is carried out, using four different plant diagrams as the power supply for the heat pump. Thermodynamic calculation of the heat pump. Calculation of the efficiency of the heat pump. Analysis of structural schemes for generating electricity using micro-thermal power plants and based on heat pumps A comparative analysis of the effectiveness of various schemes with mini-CHP. An assessment of the capital costs of installation, operation and determination of the payback period of the mini-CHP on the basis of a heat pump with various plant diagrams is carried out and the most economically advantageous scheme is selected. The practical application of the studied structural schemes is evaluated.

As one of the important components of automatic transplanter, duckbilled planting device, is a significant factor affecting the efficiency of the transplanter. Aiming at the problems of low transplanting rate, poor upright angle and poor stability of the transplanter, a five-pole transplanting mechanism is designed. Firstly, the parameters of the five-pole transplanting mechanism are analyzed and confirmed by MATALAB software. After virtual prototype model is established by SolidWorks software, simplified model is imported into ADAMS software for kinematics simulation, and then the trajectory, velocity and acceleration curve of the duckbilled tip are obtained. The simulation results verify the rationality of the structure and parameters and show that the trajectory of duckbilled planter meets the agronomic requirements of vegetable cultivation.

To further improve the structural dynamic performance of the Land-Wind X-6 chassis, structural optimization was performed: An X-shape cross member with high stiffness is added to the chassis, in addition, the cross member connecting the two torsion bar attachments is also strengthened. Extensive Finite Element Analysis (FEA) demonstrates that the inadequate torsion stiffness has been greatly increased by 102.6% after optimization, and the adequate bending stiffness has also been slightly improved by 3.8%, in addition, the level of local stresses on the chassis has been considerably declined; After optimization, the fatigue life coefficient when the vehicle is running on A-class concrete road at a speed of 110 km/h has been improved by about 40.36%, and that when the vehicle is running on D-class macadam road at a speed of 60 km/h has been improved by about 33.43%. Followed industrial implementation, field test result and product feedback information verify that the structural optimization performed in this study is effective and significant.

In this paper, a rotor test device for vertical-horizontal conversion is designed. The effects of unbalanced mass, dynamic balance position and other dynamic balance parameters on the vibration response of the rotor system are experimentally analyzed, and the difference of the vibration response of the rotor system between vertical and horizontal States is compared. The test results show that the vibration of the bearing base foot will increase after the dynamic balancing rotor is installed in the vertical shafting in the horizontal state; in order to ensure the dynamic balancing accuracy, the dynamic balancing of the vertical rotor system should be carried out on the vertical system as far as possible, and the aggravation should be carried out far away from the driving end. The research results in this paper can provide necessary support for the determination of dynamic balancing process and the study of dynamic characteristics of vertical rotors.

AUV is a powerful tool for exploration and development of marine resources. Underwater terrain matching navigation is an emerging passive autonomous navigation method, which improves the long-term and high-precision navigation capability of AUV. The underwater terrain matching algorithm based on particle filter (PF) use a large number of particle sampling to approximate the system state, which can avoid the Taylor expansion truncation error caused by the terrain linearization method, and has good matching precision and terrain adaptability. However, due to the strong nonlinearity and the uneven distribution of the underwater terrain features, it is difficult to achieve the full-range terrain matching optimize with a single configuration parameter of PF underwater terrain matching algorithm. For this reason, this paper has comprehensively studied the PF terrain matching algorithm (referred to as PF matching algorithm). The principle, accuracy and implementation steps of PF algorithm are analyzed. With the UKF algorithm as a reference, the advantages and disadvantages of PF-based algorithm are studied through computer simulation of terrain matching navigation. The matching precision and terrain adaptability of PF-based algorithm has been tested. From the simulation results, it is concluded that the particle diversity decline is one of the main factors affecting the matching performance, which provides a basis for algorithm performance improvement and engineering adaptability improvement.

In the process of micro-hole machining in EDM, if the debris and bubbles are not removed from the gap flow field, the concentration of debris and bubbles will increase, which will cause arcing discharge and seriously affect the processing efficiency and surface quality. In this paper, the geometric model of three-dimensional cylindrical gap flow field was established. The influence of bubble generation on the gap flow field and the debris under single pulse discharge condition was analyzed by Fluent. Then using the secondary development function of Fluent, the process of the debris and bubble on the bottom surface is continuously generated and the influence of bubble on the movement of debris under continuous discharge conditions were simulated and analyzed. Finally, by considering side flushing, the motion process of bubbles and debris under the conditions of flushing was analyzed.

In order to effectively identify the various faults of rolling bearings and the severity of the faults, an intelligent fault diagnosis system based on variational mode decomposition and multi-tree Mahalanobis Taguchi system with multiple mahalanobis distance was proposed. Vibration signals were decomposed into multiple BLIMFs by variational mode decomposition, and time domain and frequency domain features were extracted. The multiple mahalanobis distance method was used to solve the problem of many features in the diagnosis system. By using the advantages of Mahalanobis Taguchi system in features optimization, sensitive modal components for diagnosis and recognition were selected. Multi-tree Mahalanobis Taguchi system was constructed for intelligent identification of multiple fault states. Finally, rolling bearings fault data was tested to verify the accuracy of the algorithm and compared with other algorithms. The results show that the algorithm can simplify the diagnosis system, reduce training time and improve the recognition accuracy.

With the rapid development of clean energy and serious delay of grid construction, water abandonment is becoming more and more severe. Under this condition, this paper proposed a multi-objective model with probability constraints of trans-provincial hydropower consumption considering dynamic stability limit. Firstly, a mathematical expression about the dynamic stability limit of trans-provincial channel is constructed. Secondly, a risk assessment index of abandoned water is established on the basis of semi-absolute deviation. Then, based on the framework of stochastic programming, a multi-objective model with probability constraints is proposed for hydropower transmission in trans-provincial trade. By means of genetic algorithm with embedded Monte-Carlo simulation technology, the model can be solved efficiently. Finally, data of Tibet power grid is calculated to verify the validity and universality of the research. The results show that the established model can achieve optimal economic benefit between grid companies and generation enterprises, and also effective management of water abandonment risk.

In order to improve the modeling accuracy of the motorized spindle, a comprehensive thermal contact resistance (TCR) modeling method was proposed. The fractal theory was introduced to calculate the joint thermal contact resistance. The W-M function and the M-B fractal model were established to characterize the microscopic contour of the rough surface. The bulk thermal resistance, constrained thermal resistance, micro-gap thermal resistance and overall thermal contact resistance of the rough surface of different materials were discussed. The finite element method(FEM)was used to establish the multi-physics coupling analysis model of the motorized spindle, adding the theoretical calculation of thermal contact resistance in the joint surface of the motorized spindle. The temperature rise and deformation variation of the motorized spindle were simulated under the condition of thermal contact resistance. The simulation results demonstrate the influence of thermal contact resistance on the temperature and thermal deformation of the motorized spindle. The results show that when the thermal resistance of the high-speed motorized spindle is considered, the temperature rises and the deformation increases, and the accuracy of the model is more accurate, which is closer to the actual processing.

In order to ensure the safety and reliability of aircraft thrust management system design and reduce the risk of engineering development, the distributed optimization architecture design based on the aircraft safety method for thrust management system has been put forward in this paper. First, the thrust management function requirement is analysed; second, the distributed architecture design method for thrust management is presented by following the SAE ARP4754 and ARP4761; then the automatic take-off thrust control system function which is not available in Airbus and Boeing civil aircraft thrust management architecture is designed by using this method. The results show that the method proposed in this paper is feasible and effective. The usage efficiency of airborne computer is improved and the aircraft weight is decreased, which greatly enhanced the safety and reliability of aircraft thrust management system.

Based on the highway and railway transportation conditions of several spacecraft from Beijing to launch site, the dynamics environment data acquisition scheme is designed. The response values of sensors before vibration reduction of transport packaging box are collected throughout the whole process. The power spectral density is obtained by filtering and Fourier transform, and the peak response frequency of the excitation source of spacecraft transportation environment is analyzed. It can be used as the basis for the design of vibration reduction system for spacecraft transportation, and some suggestions for the optimization design of vibration reduction system are put forward.

In order to overcome the inconvenience of adjusting the rotor profile of twin screw compressor, the method of using cubic B-spline curve to express the rotor profile is put forward. CFD simulation analysis of the rotor compressor formed by the modified cubic B-spline curve shows that the performance of the rotor profile described by the cubic B-spline curve has little difference with that of the original profile line, and the rotor profile described by cubic B-spline curve is more convenient to modify.

Taking the unpowered model of a seaplane as the object, the blocking effect of aviation high-speed tank was studied by experimental and numerical methods in this paper. Firstly, the experiment of air field and drag were carried out in the bottom and front of the trailer. The experimental results of air field showed that the blocking effect of the air field was obvious in the bottom of trailer, while ignored in the front of trailer. The results of drag experiment under two conditions showed significant difference at mid-high speed, which proved the influence of blocking effect was obviouse. RANS method and overset grid were adopted in numerical simulation, and the accuracy of numerical method adopted in this paper was verified by comparing computed results of the model in the bottom of trailer with the experimental results. The computed results of hydrodynamic performance of the seaplane in finite and infinite domain showed that the influnence of the blocking effect of water could be nearly ignored, but the influnence of the blocking effect of air field was dominated. Finally, the hydrodynamic performance of the seaplane under the trailers with different sizes of chassis were carried out. The computed results showed that within the certain range, the degree of blocking effect of air field increased with the increase of geometrical variables of trailer chassis, further, which reached the maximum and kept constant when the variables exceeded a certain value.

With the development of electrochromic devices, the requirements for the accuracy and real-time performance of control devices are constantly increasing. For the reliability problems of single-chip microcomputer control technology, through the SOPC development platform, based on the Cydone IV core chip, the hardware design is completed by itself. The Quartus II integrated development environment is used to tailor the NIOSII real-time operating system, to achieve data collection and control. The signal is filtered using an FIR filter. The designed system has the characteristics of real-time, stability, scalability, low power consumption, etc., and can adaptively control the MOFs-based flexible electrochromic device.

Sliding bearings are widely used in submerged rolls of strip galvanizing line immersed in zinc bath. Submerged roller bearing pair materials include sleeves and bushings. These two parts are in high temperature, load and corrosive working environment. They are prone to wear and failure. The service life of bearing pair materials determines the operation time of the whole galvanizing line. In order to ensure long-term operation of galvanizing line, the most ideal method at present is to select suitable sleeve and bushing material matching pairs. To screen sleeve and bushing materials with good matching performance, a friction and wear tester simulating sleeve and bushing materials in high temperature molten zinc environment was designed and developed. The test machine is divided into three parts: driving system, loading system and heating system. The driving system drives the sample rotation of the sleeve; the loading system drives the bushing pattern to load the sample of the sleeve; the well heating furnace heats the zinc ingot to 480 °C to simulate the zinc pool environment; the vertical loading of bearing pattern and sleeve pattern, the alignment and insulation of the driving system and the loading system are comprehensively considered and solved. The stability of the test machine under test conditions is analyzed to ensure that the signal collected by the sensor has a high reference value.

The production of persimmon has a long history, however, the traditional production of persimmon depends mainly on manpower and is greatly affected by the natural weather. The yield and quality cannot be guaranteed which affects the taste, sales and word of mouth. According to the scenario design program, four kinds of user requirement models are constructed. After systematic analysis, four functional principle schemes are obtained, and five evaluation indexes are summarized. Finally, scheme 4 is selected as the most ideal scheme. Through the research and application of scenario design method in the process of product design, this paper provides an evaluation method for the evaluation of the product design, which helps designers to determine the direction of product development effectively.

As a new type of intelligent material seal technology, ferrofluid seal has been widely used in high speed, heavy load and large eccentricity occasions in recent years because of its long life, low leakage and high pressure resistance. Because of the limitation of the axial height of the axis, most of the existing studies are focused on the radial parameters, but the specific research on the axial parameters has not yet been carried out. In this study, the theoretical pressure capabilities of height of the distribution of axial teeth and axial slot width was calculated according to the theory of stepped ferrofluid seals by finite element method. And by changing the radial gap, the stepped ferrofluid seal is compared with the ordinary seal, and the calculation results are analysed and discussed. The results show that the distribution mode of the axial teeth has a great influence on the theoretical sealing pressure resistance. And the theoretical sealing pressure resistance reaches the maximum when the distribution mode is evenly distributed. The influence of the width of the axial slot on the theoretical sealing pressure resistance can be neglected, so the technological property and the design should be considered as far as possible. By comparing the stepped seal with the ordinary seal, the practicability of the stepped seal is further verified.

Starting from the actual working process of Wankel engine, the intake system model of Wankel engine is constructed based on the mean value engine model. The parameters to be determined in the model are identified by the least-square method based on the engine test data. According to the nonlinear characteristics of the intake system, the structure of the model is improved by introducing the speed correction term, and the problem that the error of original throttle air mass flow model is larger under the larger throttle opening is solved. The results of simulation and steady-state test show that the maximum relative error between simulation and experimental values of throttle air mass flow is less than +3% and that between simulation and experiment values of intake pressure is less than +2%.The parameter identification and structure of the model have high precision, which can calculate the basic air intake flow of Wankel engine accurately and shorten the development cycle of the electric control system of Wankel engine.

The purpose of this activity is to educate students and teachers with the inclusive board game invention as a learning tool for memorizing subjects for elementary to high school students. This product answers the problem for the difficulty of students remembering and understanding social science teaching materials. There are two approaches to the Learning Board Game teaching method, the first is visualization of social science teaching materials through interactive videos integrated with images according to subjects and screens and the second is gamification through the elements of challenge and fantasy by answering questions to get rewards cards or marking as a marker gets points. This product was developed with the New Product Development (NPD) Process and uses the Stage-Gate Model. In this model, product design goes through various stages starting from discovery I idea generation to launch with each stage that functions as a quality-gate of product design.

Home appliance test is an essential part of the R&D process. However, since home appliance test must be carried out under certain circumstances, it makes the development cycle longer. If it is possible to predicting the home appliance test data, it will improve the efficiency of home appliance development. Sequence to sequence model has been proved that it has a strong ability to map the input sequence and output sequence and it has been widely used in machine translation tasks. In order to solve the home appliance test data prediction problem, we firstly tried to apply sequence to sequence model to predict numerically continuous time series data. Our experiments proved that our model can predict the data of relatively long-time steps when inputting data of relatively short time steps. In our experiment, the mean absolute percentage error of the prediction of our model is about 0.1%. Our approach has a strong generalization ability and performs well in different experimental scenarios. Finally, we believe that the sequence to sequence method performs satisfactorily on prediction problems for continuous time series data. With this model, we can obtain more accurate results than traditional methods and it is meaningful for the R&D of home appliances.

With the continuous development of deep learning, neural network with its excellent self-learning performance obtains a series of a major breakthrough in target detection, image recognition and so on. In this paper, the temperature control system based on a neural network combined with I-PD compensation is proposed. To improve the neural network self-learning efficiency, the reference model is introduced for providing the teaching signal of neural network. The system simulations are carried out in MATLAB/SIMULINK environment to verify the control efficiency of the proposed reference model based neural network control system. The experiments are carried out on the DSP based temperature control system platform, the results are compared to the conventional I-PD control system to verify the control efficiency.

In the field of abstractive automatic summarization, the Seq2Seq model constructed by the RNN network is widely used and has achieved perfect results. However, due to the Seq2Seq model and the internal structure of the RNN network, only short-term and local information can be referenced in the process of generating summary, resulting the generated summary contains less information, and may even happen that the generated summary does not match the corresponding document. There have been many previous attempts to improve the model by using the attention mechanism, but only to use long-term information within a certain range. In our paper, we present a abstractive summarization model that enhances the global feature, which called Hybrid Non-Local Network model for single document summarization task, consisting of a non-local block and a traditional Seq2Seq module. Our model uses the non-local network block to transform the Seq2Seq model to better capture global feature. For example, the relationship between words and words, sentences and sentences in a large span of the original document, making the generated summary of higher quality, more informative, more accurate and rich representation of the original document. The experiments in our paper are performed on the CNN/DailyMail corpus. The proposed model was improved by 1.37, 0.47, and 1.16 onR-1 score, R-2 score, andR-L score, separately, compared to the baseline model.

Named entity recognition is an important basic task in natural language processing. This paper proposes a named entity recognition method for end-to-end and efficient deep-loop neural networks. Using BERT to train sub-vectors as raw input enables the model to obtain more comprehensive text information, and at the same time, the BiLSTM network is focused on the attention mechanism, so that the network pays more attention to the key information in the text and ignores the redundant information to improve the recognition efficiency of the model. Finally, the relationship between any two tags is captured by the CRF layer, and the entire sentence is decoded and predicted. Experiments show that the method performs well on MSRA corpus.

The vessel maintenance support system, which consist of aboard and onboard two parts, is different from the other equipments, with the characteristics of tasks varied, complex structures and onerous business. It is a virtual system rather than a material system. So the traditional modelling method which is used to describe the material objects has some defects of long communication period, weak reusability and poor expansion in describing support system in design process, which apparently cannot meet the current demands. It is imperative to introducing standardized design and modelling approach to establish the vessel support system. The study firstly analyses the function, organization, resource and operation of vessel support system. The support system modelling method is introduced based on the analysis of different view products in DODAF framework. The support system model, which is consists of organization model, activity model and information exchange matrix is given based on active based model. It can provide guidance in support system design, support concept generation under new situation, even in integrated joint operation system design in the future.

On the basis of factors influencing the evaluation of equipment transportation efficiency, such as safety, timeliness, universality and economy of system analysis, and in combination with the basic theory of Analytic Hierarchy Process (AHP), this paper sorted out the main steps for evaluation of equipment transportation efficiency, established the hierarchical chart for evaluation index of equipment transportation efficiency, proposed a comprehensive evaluation model of equipment transportation efficiency based on AHP, and verified the feasibility of this model through the specific cases. The comprehensive evaluation model of equipment transportation efficiency based on AHP proposed by this paper provides a method for the decision makers to select the optimal design scheme for equipment transportability, and lays a foundation for related studies of equipment transportability.

Smart homes are developing rapidly, and refrigerators are an indispensable part of "smart homes". Therefore, the research efficiency and quality assurance of refrigerators are highly valued by home appliance companies. Refrigerator test is required in both research and production processes. At present, the quality test of refrigerator has a high degree of manual participation, such as the selection of the stable operating range of refrigerator and the conversion of test stage require manual determination, which cause low test efficiency and high electric energy consumption. In order to solve these problems, this paper design a High-Efficiency Refrigerator Test System (HERTS) for Industrial Internet of Things (IIoT). The core test data intelligent analysis module realizes timely determination of test data and automatic transition of test stage. The proposed HERTS increases the efficiency of automate refrigerator test and greatly reduces the power consumption.