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Grain size characteristics of surface sediment and its response to the dynamic sedimentary environment in Qiantang Estuary, China

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International Journal of Sediment Research 2022年第4期37卷 457-468页

作者： Shanshan Wang Cunhong Pan Dongfeng Xie Mingwei Xu Yuhan Yan Xinwen Li Zhejiang Institute of Hydraulics & Estuary (Zhejiang Institute of Marine Planning and design) college of Harbour Coastal and Offshore EngineeringHohai University

The composition and grain size characteristics of sediment in estuarine and coastal environments provide important information on the material source, hydrodynamic environment, environmental events,etc. However, few studies have focused on the sediment characteristics of the entire Qiantang Estuary,particularly, on the correlation between hydrodynamics and sediment properties. Through systematic sampling of the surface sediment in a large area of the Qiantang Estuary, the spatial distribution characteristics of the surface sediment of the Qiantang Estuary, such as the grain size composition and particle size parameters, in different sections of the estuary area are analyzed. By comparing the particle size data of different estuaries, the similarities and differences of the particle size parameters of the Qiantang Estuary and other estuaries are compared and analyzed. According to the differences in the sediment composition, the distribution status of the particle size frequency curves and the morphological characteristics of the probability curves in the entire study area, the Qiantang Estuary is divided into 7 dynamic depositional areas: Fuchunjiang Hydropower Station-Fuyang, Fuyang-Qibao, Qibao-Cao’e River, Cao’e River-Zhapu, North Shore of Hangzhou Bay, middle part of Hangzhou Bay, and South Shore of Hangzhou Bay, which are different from the previous estuary segmentation system. The study area is divided into 13 dynamic depositional sub-regions using the Pejrup M triangle diagram. Combining the calculation results of the mathematical model and the Pejrup M triangle diagram, the relation between the dynamic deposition environment and the bottom shear stress is discussed. It is found that the spatial distribution of the bottom shear stress in the study area is in good agreement with the zoning of the dynamic sedimentary environment.

关键词： Qiantang Estuary Surface sediment Grain size parameter characteristics Dynamic sedimentary environment

Prime Mover Capacity Optimization and Thermodynamic Performance Analysis of Internal Combustion Engine Based CCHP System

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Journal of Thermal Science 2023年第4期32卷 1583-1594页

作者： WANG Shucheng MUHAMMAD Imran LI Hongwei CHEN Xiaoxu QIN Mei School of Energy and Power engineering Northeast Electric Power UniversityJilin132012China college of engineering and Physical Sciences MechanicalBiomedical and Design EngineeringAston UniversityBirminghamB47ETUK Northeast Electric Power design Institute Co. Ltd.of China Power Engineering Consulting GroupChangchun130021China

In this research,a solar hybrid combined cooling heating and power(CCHP)system is proposed considering the different scenarios of Prime Movers(PMs)and the part-load performance of PMs is validated by the designed values from the manufacturer of Volvo.Moreover,a multi-optimization model based on a genetic algorithm is developed in order to select both the most promising performance PM and the most cost-effectiveness,environmentally friendly number of collectors for the proposed CCHP system,simultaneously.Then the hourly performance of this solar hybrid CCHP is determined through a case study of a hotel in Shanghai.Results show that the highest efficiency of the PM with larger capacity has the most promising performance and the collector number of 90 turns out to be a superior value for the hotel building based on the primary energy saving ratio of 61.61%.Moreover,on a typical summer day,the recovered waste heat and the solar energy can provide all the thermal energy demands,while,an auxiliary boiler should be started to fulfill the energy gap in both typical transition and winter days.From the simulation result,the CO_(2) emissions can be reduced by 856.2 t/a due to the solar energy introduced into the system.Besides,the dynamic investment payback period will change from 3.01 years to 3.56 years when the fuel price(P_(fuel))ranges from 0.8P_(fuel) to1.2P_(fuel).

关键词： combined cooling heating and power(CCHP)system distributed energy system optimization waste heat recovery ICE

A hybrid deterministic-stochastic model for spouted beds

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Particuology 2019年第1期17卷 104-113页

作者： Shahab Golshan Reza Zarghami Navid Mostoufi Process design and Simulation Research Centre. School of Chemical engineering. college of engineering University of Tehran. TehranIran

A new hybrid deterministic-stochastic model is developed and used to simulate a slot-rectangular spouted bed.The model includes deterministic and stochastic steps that are executed in turn.The simulation starts with the deterministic part of the model,in which the computational fluid dynamics-discrete element method (CFD-DEM) equations are solved for 1 s to give the initial velocity distribution of the particles.The stochastic part is then executed,with the hydrodynamics of the bed taken from the velocity distributions acquired in the first step through Monte Carlo sampling.A full deterministic (CFD-DEM) simulation of the bed is also conducted for comparison with the proposed hybrid model.Additionally,the proposed hybrid is validated using experimental data from the literature.These validations are based on the axial and lateral velocity distributions of the particles and the bed voidage.The effects of the cell size and number of sampling steps on the accuracy of the model are also investigated.The performance of the proposed model is compared with the CFD-DEM results in terms of the computation time and the rate of solid circulation in the bed.The hybrid model is found to have shorter runtimes than the CFD-DEM approach.

关键词： CFD–DEM Monte Carlo Spouted bed Hydrodynamics Solid circulation rate

Study on time-varying seismic vulnerability and analysis of ECC-RC composite piers using high strength reinforcement bars in offshore environment

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Earthquake engineering and engineering Vibration 2022年第4期21卷 1035-1051页

作者： Liang Yan Zhao Fulin Luo Jun Chen Pei college of Civil engineering Zhengzhou UniversityZhengzhou 450001China college of Mechanics and Safety engineering Zhengzhou UniversityZhengzhou 450001China Wuhan Building Material Industry design&Research Co. LtdWuhan 430000China

As the main seismic component of a bridge,seismic damage to the bridge pier has a greater effect on its subsequent service.In the offshore chloride environment,the issues(e.g.,reinforcement bar corrosion and attenuation of concrete strength)of piers caused by chloride ion seriously curtail the normal service life and deteriorate the anti-seismic property of bridge structures.The engineered cementitious composite(ECC)-reinforced concrete(RC)composite pier with high strength reinforcement bars(HSRB)is expected to solve the above problems.This study aims to clarify the time-varying seismic vulnerability(SV)of the HSRBECC-RC composite pier during its full life cycle(FLC).Based on OpenSees,the refined finite element analysis models of RC pier,ECC-RC composite pier,and HSRBECC-RC composite pier have been established.Moreover,using the nonlinear time-path dynamic analysis method,the influence of chloride ion erosion on the time-dependent seismic vulnerability(SV)of these different piers in different service life and different peak ground acceleration(PGA)were analyzed from a dynamic point of view.The research shows that the exceeding probability(EP)of the same damage level increases with the enhancement of service time and PGA and with the increase of destruction,the exceeding probability(EP)of slight damage(DL-1),moderate damage(DL-2),serious damage(DL-3),and complete collapse(DL-4)decreases in turn;the corrosion degree of chloride ion to piers is small during the early service period,the time-varying vulnerability curve of the bridge piers is almost the same as that of a new bridge,and during later service,as the extent of chloride ion corrosion deepens,exceeding probability(EP)under severe damage(DL-3)and complete collapse(DL-4)is increased,and the seismic performance is significantly enhanced.

关键词： bridge piers engineered cementitious composite(ECC) high strength reinforcement bars(HSRB) seismic vulnerability(SV) exceeding probability(EP) full life cycle(FLC)

Investigation into precision engineering design and development of the next-generation brake discs using Al/SiC metal matrix composites

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Nanotechnology and Precision engineering 2021年第4期4卷 24-36页

作者： Jake Haley Kai Cheng Department of Mechanical and Aerospace engineering College of EngineeringDesign and Physical SciencesBrunel University LondonUxbridge UB83PHUnited Kingdom

Substantially lightweight brake discs with high wear resistance are highly desirable in the automotive industry.This paper presents an investigation of the precision-engineering design and development of automotive brake discs using nonhomogeneous Al/SiC metal-matrixcomposite materials.The design and development are based on modeling and analysis following stringent precision-engineering principles,i.e.,brake-disc systems that operate repeatably and stably over time as enabled by precision-engineering design.The design and development are further supported by tribological experimental testing and finite-element simulations.The results show the industrial feasibility of the innovative design approach and the application merits of using advanced metal-matrix-composite materials for next-generation automotive and electric vehicles.

关键词： Brake disc design Metal matrix composite Precision engineering design Tribological testing Automotive braking system Finite element analysis(FEA)and simulation

Research on Clothing Simulation design Based on Three-Dimensional Image Analysis

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Computers, Materials & Continua 2020年第10期65卷 945-962页

作者： Wenyao Zhu Xue Li Young-Mi Shon college of engineering Lishui UniversityLishui323000China Department of design Graduate SchoolChosun UniversityGwangju61452Korea Department of Materials Science and engineering Graduate SchoolChosun UniversityGwangju61452Korea design Division College Art&DesignChosun UniversityGwangju61452Korea

Traditional clothing design models based on adaptive meshes cannot reflect.To solve this problem,a clothing simulation design model based on 3D image analysis technology is established.The model uses feature extraction and description of image evaluation parameters,and establishes the mapping relationship between image features and simulation results by using the optimal parameter values,thereby obtaining a three-dimensional image simulation analysis environment.On the basis of this model,by obtaining the response results of clothing collision detection and the results of local adaptive processing of clothing meshes,the cutting form and actual cutting effect of clothing are determined to construct a design model.The simulation results show that compared with traditional clothing design models,clothing simulation design based on 3D image analysis technology has a better effect,with the definition of fabric folds increasing by 40%.More striking contrast between light and dark,the resolution increasing by 30%,and clothing details getting a more real manifestation.

关键词： 3D image analysis clothing simulation feature extraction optimal solution mapping relationship collision detection grid layout cutting effect

Research on the Intervention Effect of ArtMaking on the Anxiety Symptoms of collegeStudents

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International Journal of Mental Health Promotion 2023年第11期25卷 1237-1243页

作者： Qiuyue Wu Zhicheng Wang Tao Li Lu Wang college of Civil engineering Nanjing Tech UniversityNanjing211816China Psychological Association of college of Art&design Nanjing Tech UniversityNanjing211816China Student Affairs Office of college of Art&design Nanjing Tech UniversityNanjing211816China

This research was to investigate the intervention effect of art-making on the anxiety symptoms of college students. A sample of 400college students took part in this research. They were assigned to the experiment group (n = 200) and the control group (n = 200)according to Self-Rating Anxiety Scale (SAS) scores. Unlike the control group, the experiment group received a standard artmaking program under the supervision of trained instructors for a period of twelve sessions two times weekly which wascontinued for six weeks. Self-Rating Anxiety Seale (SAS) and Hamilton Anxiety Scale (HAMA) were used to assess anxietysymptoms level. Significant decreases in anxiety symptoms (p college students’ anxiety, and also can effectively improve the physical health, mental health, and socialhealth levels of college students.

关键词： Art-making anxiety symptoms Self-Rating Anxiety Seale(SAS) Hamilton Anxiety Scale(HAMA) college students

A Siltation Simulation and Desiltation Measurement Study Downstream of the Suzhou Creek Sluice, China

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China Ocean engineering 2013年第6期27卷 781-793页

作者：季永兴杨绯张汉云卢永金 college of Water Conservancy and Hydropower engineering Hohai University Shanghai Water engineering design and Research Institute

The Suzhou Creek Sluice is currently the largest underwater plain gate in the world, with a single span of 100 m. It is located in a tidal estuary at the junction of the Huangpu River and Suzhou Creek in Shanghai, China. In this study, physical and 2D vertical mathematical models were used to investigate and distinguish the mechanism of siltation downstream of an underwater plain gate from that of other gates types. According to quantitative data obtained by site investigation and the application of the physical hydrodynamic models, it was found that the characteristics of the tidal estuary as well as the fact that the sluice span is equal to the creek width are the major reasons contributing to siltation. A possible desiltation treatment system is proposed for the underwater plain gate. The system includes selection of a suitable location that allows the determination of a reasonable top elevation of the sluice floor, reserving sufficient space under the gate to accommodate siltation, setting up a mechanical desiltation system, and flushing silt along with overflow over the top of the gate. Furthermore, on-site hydraulic silt flushing experiments and a topography survey were conducted. These results showed that the measurement system is effective, and by maintaining this scheduled operation once a month, the downstream riverbed has been maintained in a good condition.

关键词： tidal estuary underwater plain gate siltation sluice Suzhou Creek

A Privacy-preserving Algorithm for AC Microgrid Cyber-physical System Against False Data Injection Attacks

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Journal of Modern Power Systems and Clean Energy 2023年第5期11卷 1646-1658页

作者： Jun Yang Yu Zhang college of Information Science and engineering Northeastern UniversityShenyangChina Liaoning Provincial Transportation Planning and design Institute Co. Ltd.ShenyangChina

A new privacy-preserving algorithm based on the Paillier cryptosystem including a new cooperative control strategy is proposed in this paper, which can resist the false data injection(FDI) attack based on the finite-time control theory and the data encryption strategy. Compared with the existing algorithms, the proposed privacy-preserving algorithm avoids the direct transmission of the ciphertext of frequency data in communication links while avoiding complex iterations and communications. It builds a secure data transmission environment that can ensure data security in the AC microgrid cyber-physical system(CPS). This algorithm provides effective protection for AC microgrid CPS in different cases of FDI attacks. At the same time, it can completely eliminate the adverse effects caused by the FDI attack. Finally, the effectiveness, security, and advantages of this algorithm are verified in the improved IEEE 34-node test microgrid system with six distributed generators(DGs) in different cases of FDI attacks.

关键词： AC microgrid cyber-physical system(CPS) distributed cooperative control false data injection(FDI)attack Paillier cryptosystem