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    Journal of Diagnostics Concepts & Practice    2021, 20 (04): 317-337.   DOI: 10.16150/j.1671-2870.2021.04.001
    Abstract10050)   HTML545)    PDF(pc) (3337KB)(9599)       Save
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    Low-Carbon Transformation of the Power System in the Guangdong-Hong Kong-Macao Greater Bay Area
    ZHANG Pengfei, XU Jingyi, GUO Wei, WU Wei, ZHONG Chen, WEI Wendong
    Journal of Shanghai Jiao Tong University    2022, 56 (3): 293-302.   DOI: 10.16183/j.cnki.jsjtu.2021.436
    Abstract4254)   HTML391)    PDF(pc) (2818KB)(765)       Save

    China’s “carbon peaking and carbon neutrality” goal relies greatly on the low-carbon transition of the power system, but the existing research rarely explores the low-carbon transition of the regional power system. By using the intergovernmental panel on climate change (IPCC) greenhouse gas inventory compilation method and the network model analysis, the carbon emissions caused by the power generation and the power consumption in Guangdong-Hong Kong-Macao Greater Bay Area (the Greater Bay Area) was quantified. The logarithmic mean Divisia index (LMDI) method was used to quantify the influence of socio-economic factors on the electricity-related carbon emissions in the Greater Bay Area. The results show that Hong Kong and Macao have made slow progress in the low-carbon transition of the power system, and Guangdong’s share of the low-carbon power continues to increase. The rapidly expanding economic scale and the power demand were the most important drivers of the emissions growth in the Greater Bay Area. The low-carbon electricity imported from outside regions and the improved efficiency in the sectoral electricity consumption offset part of the emission growth.

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    Optimization of Active Distribution Network Operation Considering Decarbonization Endowment from 5G Base Stations
    ZENG Bo, MU Hongwei, DONG Houqi, ZENG Ming
    Journal of Shanghai Jiao Tong University    2022, 56 (3): 279-292.   DOI: 10.16183/j.cnki.jsjtu.2021.367
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    The massive access of 5G base stations (5G BSs) provides new possibilities for the low-carbon development of future power systems. By incentivizing 5G BSs to participate in demand response and incorporating them into the existing active distribution network (ADN) operation framework, the cost of the electricity consumption of 5G BSs can be reduced while promoting the consumption and efficient use of renewable energy sources (RES). This paper proposes a multi-objective interval optimization model for ADN operation considering low-carbon empowerment of 5G BSs. Based on the interaction mode between 5G BSs and the distribution network, a 5G BSs operating flexibility description model is constructed, and the system dynamics method is used to reveal the mechanism of 5G BSs on carbon emission reduction on the distribution side. Taking the minimization of system operating cost and carbon emissions as the goals, and considering the constraints for both the distribution network and the communication network, a multi-objective optimization model for ADN operation with 5G BSs is established. The model cooptimizes the dispatch of RES and 5G equipment, and adopts an interval method to consider the uncertainty of RES output and communication loads, which can achieve simultaneous optimization of system economy and low-carbon benefits. Combining the equivalent transformation and the non-dominated sorting genetic algorithm to solve the problem, the results of numerical studies prove the effectiveness of the proposed method.

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    Control Strategies for Suppressing Frequency Oscillation of Doubly-Fed Wind Farms Connected to Grid
    LIU Xinyu, LU Xinyan, ZENG Long, HAO Zhenghang, ZHAO Qifang, LI Xianwei, HAO Tongmeng
    Journal of Shanghai Jiao Tong University    2022, 56 (3): 303-311.   DOI: 10.16183/j.cnki.jsjtu.2021.437
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    Aimed at the problem of low-frequency oscillations caused by cross-region power transmissioin of large-scale wind farms, a single neuron adaptive proportion integration differentiation (PID) additional damping control strategy for low-frequency oscillations of the damping system is proposed in this paper. By analyzing the dynamic frequency response characteristics of doubly-fed wind turbines, a wind farm damping system oscillation controller is constructed by introducing quadratic performance indicators into the single neuron adaptive PID control algorithm. By adaptively adjusting the excitation frequency converter, the wind farm can quickly generate active power and the maximum positive damping, and suppress the low-frequency oscillation of the damping system. MATLAB is used to build a four-machine two-region power system simulation model with a wind farm. The comparison verifies that the method proposed in this paper can effectively suppress the swing of the power angle of the synchronous generator when low-frequency oscillation occurs in the system, improve the inertial response of the system, and reduce the risk of low-frequency oscillation in the power grid.

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    A Review of Coupled Electricity and Hydrogen Energy System with Transportation System Under the Background of Large-Scale New Energy Vehicles Access
    LI Jiaqi, XU Xiaoyuan, Yan Zheng
    Journal of Shanghai Jiao Tong University    2022, 56 (3): 253-266.   DOI: 10.16183/j.cnki.jsjtu.2021.464
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    The large-scale utilization of renewable energy is an important way to achieve the “double carbon targets”. The technology of coupled renewable energy with hydrogen system can improve the consumption rate of renewable energy and the penetration of new energy vehicles. The coupling between the electricity-hydrogen energy system and the transportation system will be even closer in the future. Based on the access of large-scale new energy vehicles, first, the development of the electricity and hydrogen energy system was summarized, and the three working modes of electricity-hydrogen coupling system including hydrogen production, output smoothing, and coordinated operation with electricity network were introduced. Then, the research status of the electricity-transportation coupling system on planning and optimal operation, and the problems of hydrogen-transportation coupling system on hydrogen refueling station optimization and hydrogen transportation were analyzed. Finally, in combination with the existing bottlenecks, the future feasible research directions such as dynamic model construction and the influence of uncertain factors were proposed.

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    Dynamics Modeling and Validation of Coaxial Lifting Rotors
    HU Jinshuo, HUANG Jianzhe
    Journal of Shanghai Jiao Tong University    2022, 56 (3): 395-402.   DOI: 10.16183/j.cnki.jsjtu.2021.044
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    The dynamics model for coaxial lifting rotors can be used to study the controller design and flight simulation for coaxial-rotor aerial vehicles. However, both the computational efficiency and the accuracy should be considered. First, the computational model of the induced velocity of lifting rotor everywhere including the wake region is derived based on adjoint theorem. Then, the finite state dynamics model for coaxial lifting rotors with wake skew considered is developed by extending the finite state inflow model for single rotor. Finally, the equations for calculating the thrust of coaxial lifting rotors in the hover condition are given, and the test is conducted. The results show that the computational complexity of the proposed dynamics model for coaxial lifting rotors is acceptable, and the computational thrusts are almost close to the test results when the rotational speed is within a certain range, which can also reflect the trend of the thrust lost for coaxial lifting rotors.

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    Uncertainty Analysis of Offshore Platform Wind Load Tests
    DAI Yi, CHEN Zuogang, WANG Fei
    Journal of Shanghai Jiao Tong University    2022, 56 (3): 361-367.   DOI: 10.16183/j.cnki.jsjtu.2021.066
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    The superstructures of offshore platforms are usually complex in shape, and wind tunnel test is the most reliable method to obtain the wind loads. Few researches about the procedures of uncertainty analysis (UA) and key points have been conducted, and the influences of error sources are not clear. The UA of an offshore platform wind load tests is first performed based on the International Towing Tank Conference (ITTC) recommended procedures. According to the wind load test procedure of the offshore platform, the uncertainties due to many error sources are analyzed. In order to obtain the remark of all error sources and propose the approach of reducing uncertainties, error sources are evaluated and graded. The results show that the wind profile, the accuracy of the model, the air pressure measurement, and the balance measuring state have a great influence on wind load coefficients, which contribute to 96.13% of the combined uncertainty. The uncertainties can be effectively reduced by model simplification, high quality wind profile, high precision air pressure measurement, and stable measurement state.

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    Numerical Simulation and Analysis of Cylindrical Ice Impacting Problem
    WANG Chao, YANG Bo, ZHANG Yuan, GUO Chunyu, YE Liyu
    Journal of Shanghai Jiao Tong University    2022, 56 (3): 368-378.   DOI: 10.16183/j.cnki.jsjtu.2020.278
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    In order to study the application characteristics of the peridynamics (PD) method in the field of ice mechanical behavior and the sensitivity analysis of parameter changes in the numerical prediction of ice failure, the ordinary state-based peridynamic method is employed to systematically analyze the impact failure process of cylindrical ice in the present work. The results show that the simulated ice impact process by the proposed method is basically consistent with the test results, and the calculation results converge under the selected time step and particle spacing. The impact velocity, Poisson’s ratio, and the elastic modulus of the ice have remarkable effects on the impact process of ice cylinder, while the size and fracture toughness of the ice only have little influence. The innovation of this paper lies in the fact that the state-based PD method is applied to study the ice impact problem, which compensate for the shortcomings of the bond-based PD method that limits the Poisson’s ratio of the ice.

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    Review of Research on Condition Assessment of Nuclear Power Plant Equipment Based on Data-Driven
    XU Yong, CAI Yunze, SONG Lin
    Journal of Shanghai Jiao Tong University    2022, 56 (3): 267-278.   DOI: 10.16183/j.cnki.jsjtu.2021.502
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    The condition assessment of the entire life cycle of nuclear power equipment has a significant impact on improving the safety and economy of nuclear power plants. In the past, operation and maintenance of systems, equipment, and structures of domestic nuclear power plants, mostly relied on the alarm mechanism of equipments, the simple threshold judgments of parameters, or the empirical judgments of engineers. With the implementation of online monitoring system in nuclear power plants, a large number of equipment operation data have been accumulated, and the use of data-driven technology to assess the health of equipment has become the focus of attention in the industry. In this paper, the current situation of the online monitoring system of nuclear power equipment was introduced and the common malfunction of nuclear power equipment was analyzed. The condition assessment of nuclear power equipment were categorized into three major problems (i.e., anomaly detection, life prediction, and fault diagnosis), the situation of research and application were summarized respectively, and the application potential of deep learning technology in this field was emphasized. Based on this, the challenges and possible solutions to the condition assessment of nuclear power plant equipment were further analyzed.

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    LU Dihua, CHEN Ziqiang
    Journal of Shanghai Jiao Tong University    2022, 56 (3): 342-352.   DOI: 10.16183/j.cnki.jsjtu.2021.027
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    Aimed at the uncertainty of charging starting and ending point caused by incomplete charging and discharging in practical applications of lithium-ion battery, an estimation method of battery health based on dual charging state factors is proposed. A battery aging experiment bench is built, and eight nickel-cobalt-manganese lithium-ion batteries are subjected to aging test. Different from the traditional single state factor estimation, the average value of equal time difference current at the front end of constant voltage charging curve and the equal amplitude voltage charging time at the end of constant current charging curve are selected under different aging conditions to construct health factors. The corresponding relationship between state of charge (SOC) and open circuit voltage (OCV) of the experimental battery in different aging states is analyzed and the correctness of health factor is proved by theoretical deduction and experimental results. An improved support vector regression model with a strong generalization ability is established, and the hyperparameters of the model are optimized through the particle swarm optimization algorithm. The results show that the proposed dual-charging health factor is closely related to battery capacity aging and attenuation. The improved support vector regression model can estimate the health status in different aging states in real time, and has the ability to characterize local capacity rebound change, which can be used as an effective method for estimating the state of health of an embedded battery management system.

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    Influence of Pressurization Methods on Cryogenic Helium Pressurization in Rocket Fuel Tank
    ZOU Zhenfeng, REN Feng, LI Xiaoci, DUAN Haiyang, DU Hailang, HUANG Yonghua
    Journal of Shanghai Jiao Tong University    2022, 56 (3): 386-394.   DOI: 10.16183/j.cnki.jsjtu.2020.265
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    To verify the technical scheme of cryogenic helium pressurization in the fuel tank of liquid oxygen (LOX)-kerosene rocket, a test device was established and the ground simulation test was conducted. The influences of different pressurization methods on pressure control stability, ullage temperature distribution in tank, helium consumption, gas-liquid mixture, and liquid freezing of pressurized drainage process were investigated. The pressurization method specifically includes pressurization outlet position, diffuser form, and pressurant flow rate. The results show that when pressurized from the liquid zone, the heat exchange of pressurized gas is more sufficient, which reduced the gas consumption by 33.1% compared with that in the ullage zone. However, the stability of pressure control is less satisfying. The form of diffuser has little influence on the gas consumption and the temperature distribution of ullage. The helium consumption for pressurization at a small flow rate is less than that at a high flow rate. For example, when the drainage flow is 10 L/s, the helium consumption can be reduced by 20% compared with that at 40 L/s. Under all experimental conditions, neither ice due to local supercooling in the tank nor bubbles in the drainage pipeline are observed. The test results verify the feasibility of the proposed scheme, and provide a reference for structural design and working condition regulation of the cryogenic helium pressurization system in rocket.

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    A Suppression Strategy for Subsequent Commutation Failures Considering Commutation Capability of Recovery Process
    CONG Xinpeng, ZHENG Xiaodong, CAO Yaqian, TAI Nengling, MIAO Yuancheng, LI Ke
    Journal of Shanghai Jiao Tong University    2022, 56 (3): 333-341.   DOI: 10.16183/j.cnki.jsjtu.2021.004
    Abstract3741)   HTML237)    PDF(pc) (1969KB)(478)       Save

    In order to suppress subsequent commutation failures of high voltage direct current (HVDC), the dynamic process of electrical and control quantities during system recovery is studied, and the main reason for subsequent commutation failures is proposed in the paper. During the recovery process, the voltage of the converter bus after the fault is in a state of drop, the actual firing angle of the inverter is in overshoot, and direct current continues to rise. These factors result in an insufficient system commutation capability to complete the transfer of valve arm inductance energy during the commutation process. A suppression strategy for subsequent commutation failure considering the commutation capability of the system recovery process is proposed. By limiting the direct current (DC) when the firing angle is in overshoot, the system commutation capability is increased, and subsequent commutation failures are suppressed. In addition, the DC system is effectively recovered. The proposed theory is tested and verified based on the HVDC CIGRE Benchmark in PSCAD/EMTDC.

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    Performance Evaluation Index and Method of Micro-Grid Distributed Electricity Trading Under the Background of “Carbon Peaking and Carbon Neutrality”
    WANG Wenbin, ZHENG Shujiang, FAN Ruixiang, CHEN Wen, ZHOU Shiyang
    Journal of Shanghai Jiao Tong University    2022, 56 (3): 312-324.   DOI: 10.16183/j.cnki.jsjtu.2021.391
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    With the rapid development of distributed power generation research and application, the distributed trading market, as a new type of power trading mode, can effectively increase the consumption rate of renewable energy and is an important means to promote the realization of the goal of “carbon peaking and carbon neutrality”. Introducing the market evaluation mechanism into distributed transactions will prompt users to consider the impact of the market evaluation mechanism on their trading strategies and promote the sound development of the distributed transaction market. The distributed power trading market among micro-grid users is studied in this paper. First, taking the market participants and transaction supporting software and hardware as the research object, a multi-dimensional performance evaluation index system is established from the aspects of power supply capacity, user satisfaction, and platform security. Next, the research status of distributed power trading market evaluation methods is summarized. The key technologies of distributed power trading performance evaluation are analyzed from the establishment of index system, the index calculation method, and the comprehensive evaluation method. Finally, in combination with the current development status, the research direction of the distributed power trading performance evaluation in the future is prospected.

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    Optimization of Control Scheme for Large Flow Seawater Cooling System Based on FloMaster-Simulink Co-Simulation
    WANG Ning, FU Yunpeng, LI Ting, LI Tie, YI Ping
    Journal of Shanghai Jiao Tong University    2022, 56 (3): 379-385.   DOI: 10.16183/j.cnki.jsjtu.2021.023
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    Large-scale marine equipment will overheat if it works for a long time and a cooling system is necessary to be established to ensure that the equipment works in a safe range of temperature. To meet the cooling requirements of a large-scale marine equipment, a model of seawater cooling system is established in FloMaster, and simulations under dynamic conditions are conducted. According to the temperature of the coolant (glycol solution) in the front or back of the room of the heat exchanger, the pump speed or valve opening is changed to realize automatic control of seawater flow. Three control schemes are proposed, and the control effects are evaluated by the response characteristics and operating characteristics of the system under variable working conditions using the FloMaster-Simulink co-simulation method. The results show that when the pump speed is controlled by both the open loop and closed loop, the best control effect and lower energy consumption can be achieved.

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    A Dual Cooperative Optimization for Optimal Redundancy Quantity of MMC Submodules of Flexible Controller
    MA Zhoujun, WANG Yong, WANG Jie, CHEN Shaoyu
    Journal of Shanghai Jiao Tong University    2022, 56 (3): 325-332.   DOI: 10.16183/j.cnki.jsjtu.2021.444
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    The failure of modular multilevel converter (MMC) submodules in the flexible direct current (DC) system affects the normal operation of the system, and the mutual restriction of reliability and economy is one of the key issues of MMC redundancy configuration optimization. A multi-objective optimization function of MMC reliability and economy mathematical model with redundant submodules was established. Based on the weight coefficient and NSGAII multi-objective optimization methods, a dual collaborative optimization for redundancy quantity of flexible controller was proposed. Combining the advantages of the two methods, the intersection of the two optimization results was calculated under the same redundancy quantity selection preference. A model based on a DC project in a flexible station area of Nanjing was built in MATLAB. The simulation results prove that the proposed method can not only meet the reliability of the flexible DC system, but also significantly improve the economy. It provides ideas for redundancy quantity of MMC submodules in the actual flexible DC project.

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    An Improved TDOA Lightning Location Approach Considering L-M Algorithm and Acoustics
    LUO Yaoying, BIAN Hongzhi, LIU Quanzhen, LIU Baoquan, FU Zhengcai, ZHANG Jianxun, LIU Yakun
    Journal of Shanghai Jiao Tong University    2022, 56 (3): 353-360.   DOI: 10.16183/j.cnki.jsjtu.2020.301
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    In the conventional lightning location system (LLS) based on time difference of arrival (TDOA), the nonlinear equations in lightning location calculation easily get to be divergent when the time information acquired from electromagnetic sensors is redundant. The LLS setup in lightning-sensitive regions in China usually experiences a development from detecting the thunderclap signal to the electromagnetic signal, such as the LLSs in oil tank farms. Therefore, an improved TDOA lightning location approach was proposed considering the acoustic and electromagnetic information emitted from lightning discharges. The targeted lightning monitoring region was divided into 16 sub-regions according to the location of the existing detection stations. The lightning location was calculated based on the Levenberg-Marquardt (L-M) iterative algorithm, which improves the lightning location accuracy and the resistance ability to measuring errors. The results show that the average error of the traditional lightning location method is 203.2 m. In contrast, the proposed approach can reduce the lightning location error to 108.4 m by considering the acoustic information and L-M iteration algorithm. The location accuracy at the edge of the targeted area is improved by 51.2%. This research can be potentially counseled in the improvement of existing LLSs and making an effective use of acoustic information.

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    Transknowletology: Its Naming and Concept Construction,
    MENG Xiangchun
    Contemporary Foreign Languages Studies    2022, 22 (3): 55-64.   DOI: 10.3969/j.issn.1674-8921.2022.03.007
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    With cross-cultural interaction between local knowledge and global knowledge as its fundamental rationale, and with knowledge and culture synthesized in this conception, Transknowletology, proposed by Yang Feng, integrates “knowledge” in the ontological sense into Translatology, thereby constructing a fundamentally and ultimately knowledge-centered translation theory whose major inquiry focuses on “knowledge translation” and “translated knowledge” essentially in the framework of translation studies. If it should develop following the path of “studies of knowledge translation”, the term “knowledge translation studies”, therefore, may serve as its proper name. If it develops as knowledge-rooted-and-centered translation studies, as it is intended, Transknowletology may be its possible, if not the best, name. By virtue of the naming of “Transknowletology” per se, a series of new concepts or discourses can be reversely constructed, such as “knowledge glocalization”, the “scissors differential of knowledge”, “knowledge impact”, “knowledge-culture entanglement”, the “ripple effect of knowledge”, and the “knowledge translation paradox”, thus enriching and empowering the theory in question. A complete, mature Transknowletology necessitates a proper definition of “knowledge”, the establishment of translation criteria, the organic synthesis of newly constructed concepts and discourses, self-introspection with “others” as frames of reference, and engagement in global scholarship through discourse featuring “comparative glocalism”. These endeavors may enrich and even reshape global translation studies.

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    Optimal Reconfiguration Method for Thermoelectric Power Array Based on Artificial Bee Colony Algorithm
    YANG Bo, HU Yuanweiji, GUO Zhengxun, SHU Hongchun, CAO Pulin, LI Zilin
    Journal of Shanghai Jiao Tong University    2024, 58 (1): 111-126.   DOI: 10.16183/j.cnki.jsjtu.2022.284
    Abstract2508)   HTML6)    PDF(pc) (9997KB)(87)       Save

    With the rapid development of new energy generation technology, the thermoelectric generation technology (TEG) can make good use of the waste heat generated in new energy generation. However, the change of temperature distribution will worsen the output characteristics and reduce the power generation efficiency of the TEG system. In this paper, a TEG array reconfiguration method based on the artificial bee colony (ABC) algorithm is proposed. In three different temperature distributions, ABC is used for dynamic reconfiguration of symmetric 9×9 and unsymmetric 10×15 TEG arrays. Three meta-heuristic algorithms, the genetic algorithm, the particle swarm optimization algorithm, and the bald eagle search are compared with the proposed method, and the temperature distribution of the TEG array reconfiguration by ABC is given. The results show that ABC can improve the output power of the TEG array, and the output power-voltage curves tend to show a single peak value. In addition, real-time hardware-in-the-loop (HIL) experiment based on the RTLAB platform is undertaken to verify the implementation feasibility.

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    Interpretation on the report of global stroke data 2022
    TANG Chunhua, GUO Lu, LI Qiong, ZHANG Lili
    Journal of Diagnostics Concepts & Practice    2023, 22 (03): 238-246.   DOI: 10.16150/j.1671-2870.2023.03.06
    Abstract2451)   HTML127)    PDF(pc) (2270KB)(1840)       Save

    In 2022, the World Stroke Organization released two new reports regarding global stroke statistics in the International Journal of Stroke. The reports updated the global incidence and mortality of stroke, evaluated the effects of gender and geographic factors, and provided updated statistics on attributable risk factors associated with stroke. This article briefly interprets the two reports in the context of stroke prevalence and disease burden in China. 2019 Global Burden of Disease Study findings show that stroke remains the second-leading cause of death and the third-leading cause of death and disability combined in the world. From 1990 to 2019, the burden (in terms of the absolute number of cases) increased substantially, with the bulk of the global stroke burden residing in lower-income and lower-middle-income countries. Moreover, people under 70-year-old were observed to have significant increases in stroke prevalence and incidence. The five major risks for stroke globally include high systolic blood pressure, high body mass index, high fasting glucose, environmental particulate matter pollution, and smoking. Stroke prevention and treatment in China are facing great challenges. Stroke has become the leading cause of death and disability among Chinese adults, as well as the leading cause of disability adjusted life year lost. The incidence, prevalence and mortality of stroke in China are geographically high in the north, low in the south and prominent in the central part of the country; the prevalence is higher in rural areas than that in urban areas; the morbidity and mortality rates are higher in men than those in women; the average age of onset is lower than in developed countries; the overall disease burden of ischemic stroke is on the rise, but that of hemorrhagic stroke is on the decline. The awareness of stroke prevention and treatment was low. In conclusion, it is of strategic importance to actively establish a graded stroke prevention and control system that meets the national conditions.

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    Report on diagnosis and treatment of hemophilia in China 2023
    XUE Feng, DAI Jing, CHEN Lixia, LIU Wei, ZHANG Houqiang, WU Runhui, SUN Jing, ZHANG Xinsheng, WU Jingsheng, ZHAO Yongqiang, WANG Xuefeng, YANG Renchi
    Journal of Diagnostics Concepts & Practice    2023, 22 (02): 89-115.   DOI: 10.16150/j.1671-2870.2023.02.001
    Abstract2305)   HTML69)    PDF(pc) (1494KB)(1719)       Save

    In recent years, China attaches great importance to the prevention and treatment of rare diseases. As one of the representative diseases of rare diseases, management of Hemophilia has made great progress in China. From 1986 to 1989, the National Hemophilia Cooperative Group conducted China's hemophilia epidemiological survey according to the unified method and standard, and the results showed that the prevalence of hemophilia was 2.73/100 000, and there was no statistical difference in prevalence among different regions. In 2014, Meta-analysis showed that the prevalence of hemophilia in China was 2.8/100 000, and in 2018, based on the data of the urban population of Tianjin, the local prevalence of hemophilia was estimated to be 3.09/100 000. With the comprehensive promotion of the construction of hemophilia hierarchical diagnosis and treatment system, China requires that hospitals applying for hemophilia comprehensive management centers and diagnosis and treatment centers must be able to independently carry out screening tests and confirmatory tests related to hemophilia diagnosis. For diagnosis of hemophilia, most laboratories in China usually adopt the one-stage method (coagulation method) based on the activated partial thromboplastin time (APTT) for the determination of coagulation factor activity, but it should be noted that more than two activity detection methods are required for some special types of hemophilia. The types of each mutation in the F8 gene of patients in China are similar to those reported in international data, and the mutations in the F9 gene of our patients are mainly single base point mutations, with no mutation hotspots found. As of June 2023, a total of more than 40 000 cases with inherited bleeding disorders registered in 261 centers in China (including hemophilia), through the National Hemophilia Registration System. The history of hemophilia treatment in China has been explored through inadequate on-demand and low-dose prophylaxis, and is now moving towards higher-dose prophylaxis and individualized prophylaxis with higher efficacy. Based on the above registry data and literature, this report comprehensively summarizes the progress of basic and clinical research and medical protection in the field of hemophilia in China, and analyzes the shortcomings for further improvement of hemophilia diagnosis and treatment in China.

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    Behavior of Pull-Out and Movement Mechanisms of High-Performance Plain Weave Fabric Yarns
    CHEN Jianwen, WU Shanxiang, ZHANG Ruonan, CHEN Wujun, FAN Jin, WANG Mingyang
    Journal of Shanghai Jiao Tong University    2022, 56 (4): 464-473.   DOI: 10.16183/j.cnki.jsjtu.2020.419
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    In order to study the movement mechanisms of plain weave fabric yarns, the numerical simulation of behavior of yarn pull-out and movement under various loading conditions was carried out on a typical plain-woven fabric. The effects of friction coefficients, model size, and pre-stress levels on yarn movement responses were analyzed in detail, and the coupling relation among pull-out length, pull-out fractured strength, and model parameter conditions, including friction coefficients and pre-stress levels were shown. The results indicate that positive correlations exist between peak pull-out loads and those main model parameters of plain weave fabrics, including the friction coefficients, model size, and pre-stress levels. As the pre-stress level rises from 200 MPa to 700 MPa, the peak pull-out load increases by 34.49%, and the existence of yarn crimps could lead to improvement of the pull-out loads. The pull-out fractured strength of yarns gradually increases with the growths of pre-stress levels and friction coefficients in the plain weave fabrics. Specifically, the pull-out fractured strength of yarns increases by 16.48% as the friction coefficient grow from 0.1 to 0.2. In addition, the pull-out fractured length of yarns of the plain-woven fabrics is highly dependent on the actual stress state, and the homogenization of the stress state is an important factor that influences the pull-out fractured length.

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    Low-Carbon Operation Strategy of Integrated Energy System Based on User Classification
    ZHANG Chunyan, DOU Zhenlan, BAI Bingqing, WANG Lingling, JIANG Chuanwen, XIONG Zhan
    Journal of Shanghai Jiao Tong University    2024, 58 (1): 1-10.   DOI: 10.16183/j.cnki.jsjtu.2022.321
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    Integrated energy system (IES) is an important means to achieve the goal of “carbon peaking and carbon neutrality”. However, different types of users in the system have different energy consumption behaviors, which makes the coordinated optimization and low-carbon operation of the integrated energy system more difficult. In order to give full play to the subjective initiative of users, the user behavior of the integrated energy system is modelled based on user behavior analysis, and users are classified into aggressive and conservative types by convolutional neural network (CNN). Then, the decision model of integrated energy system operator is constructed to determine the supply mode of electric heating energy, and the corresponding energy package is designed for different types of users. Finally, the effectiveness of the above models and methods is analyzed based on actual data, and the value of user classification in low-carbon operation of integrated energy systems is verified.

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    Numerical Simulation Strategy Optimization Analysis of Submarine Resistance and Flow Field
    LI Peng, WANG Chao, SUN Huawei, GUO Chunyu
    Journal of Shanghai Jiao Tong University    2022, 56 (4): 506-515.   DOI: 10.16183/j.cnki.jsjtu.2020.327
    Abstract2089)   HTML188)    PDF(pc) (13748KB)(785)       Save

    In order to explore the influence of different turbulence models on the resistance and flow field of an advancing submarine, based on the STAR-CCM+platform, and taking Sub-off as the geometric model, this paper adopts the finite volume method, combing 10 turbulence models to conduct numerical research on hydrodynamic and flow field characteristics of Sub-off. First, the LES-Smagorinsky turbulence model is used for the convergence of grids and time steps. Then, the appropriate grid and time step are selected to calculate 10 kinds of turbulence models in specific cases. Finally, the selected turbulence model is used to analyze the hydrodynamic characteristics and flow fields of Sub-off. The results show that there are great differences among the 10 turbulence models in the prediction of submarine hydrodynamic performance and flow field characteristics. LES-Smagorinsky can not only predict the hydrodynamic performance and the average flow field of submarine, but also accurately predict secondary variables of flow fields.

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    Improved Magnetic Circuit-Motion Coupled Model and Fast Simulation of Direct-Acting Electromechanical Motion Device
    JIANG Peng, GUAN Zhenqun, ZHAO Guozhong, ZHANG Qun, QIN Zhiqiang
    Journal of Shanghai Jiao Tong University    2024, 58 (1): 102-110.   DOI: 10.16183/j.cnki.jsjtu.2022.243
    Abstract2083)   HTML2)    PDF(pc) (3985KB)(126)       Save

    The rapid simulation of the dynamic performance of electromechanical devices such as solenoid valves and relays is important for product development and design. A magnetic circuit model of the non-saturated direct-acting electromechanical motion device is improved, and then coupled with the motion equation of the mechanism to realize the rapid simulation of the electromechanical motion device. In contrast to the ideal magnetic resistance in the conventional magnetic circuit model, the non-saturated total magnetic resistance is expressed by a cubic polynomial of the movement displacement of mechanism. The four undetermined coefficients of the polynomial are calibrated by the simulation values of static magnetic force and inductance at the upper and lower motion limits. The improved magnetic circuit model can more accurately predict the changes of magnetic attraction force and inductance with the motion displacement. Furthermore, coupled with the motion equation of the electromechanical motion device, the improved model establishes an improved magnetic circuit-motion coupled model and realizes fast second-level simulation of an electromagnetic brake and valve in the Simulink system, which can greatly reduce the finite element simulation time while maintaining simulation accuracy.

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    Underwater Image Enhancement Based on Generative Adversarial Networks
    LI Yu, YANG Daoyong, LIU Lingya, WANG Yiyin
    Journal of Shanghai Jiao Tong University    2022, 56 (2): 134-142.   DOI: 10.16183/j.cnki.jsjtu.2021.075
    Abstract1996)   HTML59)    PDF(pc) (22386KB)(857)       Save

    This paper proposes an underwater image correction and enhancement algorithm based on generative adversarial networks. In this algorithm, the multi-scale kernel is applied to the improved residual module to construct a generator, which realizes the extraction and fusion of multiple receptive fields feature information. The discriminator design considers the relationship between global information and local details, and establishes a global-region dual discriminator structure, which can ensure the consistency of overall style and edge texture. An unsupervised loss function based on human visual sensory system is proposed. Reference image constraints are not required, and the confrontation loss and the content loss are jointly optimized to obtain better color and structure performance. Experimental evaluations on multiple data sets show that the proposed algorithm can better correct color deviation and contrast, protect details from loss, and is superior to typical algorithms in subjective and objective indexes.

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    Numerical Simulation and Experimental Research of Sheet Hemming Forming Based on Adhesive Filling
    TANG Genglin, LI Jianjun, LI Yuanhui, ZHANG Longyao, ZHU Wenfeng
    Journal of Shanghai Jiao Tong University    2022, 56 (4): 523-531.   DOI: 10.16183/j.cnki.jsjtu.2020.429
    Abstract1993)   HTML139)    PDF(pc) (11461KB)(720)       Save

    The filling rate of adhesive is defined based on the geometric dimensions of the hemming model, and the numerical simulation model of the hemming process with adhesive is established by using the finite element method-smoothed particle hydrodynamics (FEM-SPH) method. By comparing and verifying with the hemming experiment with adhesive, the quantitative study of the influences of the hemming adhesive diameter, the edge distance, and the hemming thickness on the filling rate is realized. The research results show that the flow state and the final filling state of the adhesive layer obtained in the experiment are similar to the numerical simulation results, and the filling rate of the adhesive layer obtained in the experiment is highly consistent with the numerical simulation result, which verifies the feasibility and accuracy of the numerical simulation model. Further analysis shows that the influences of the hemming adhesive diameter, the edge distance, and the hemming thickness on the filling rate decrease in order, and the relationship formulas between the filling rate and process parameters, such as the hemming adhesive diameter, the edge distance, and the hemming thickness, are obtained by fitting, which provides a basis for the optimization design of the hemming process with adhesive of the automobile body sheet.

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    Modeling and Experiment on Roll-Hemming Forming Process of Aluminum Alloy Sheet with Adhesive
    LI Yuanhui, LI Jianjun, WANG Shunchao, ZHANG Longyao, ZHU Wenfeng
    Journal of Shanghai Jiao Tong University    2022, 56 (4): 532-542.   DOI: 10.16183/j.cnki.jsjtu.2021.198
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    In the roll-hemming forming process of door cover, the non-metallic flanging adhesive and the interaction between light metal and flanging adhesive will affect the manufacturing accuracy and performance of the door cover, and increase the difficulty of roll-hemming forming and quality control of automobile body sheet with adhesive. Therefore, a numerical analysis model for roll-hemming forming of aluminum alloy sheet with adhesive was proposed based on the finite element method and the smooth particle hydrodynamic (FEM-SPH) method. First, SPH was used to simulate the extrusion flow process of the flanging adhesive, and a roll-hemming simulation model of sheet metal with adhesive was established in combination with FEM. Then, an experimental platform for two-pass roll-hemming forming of aluminum alloy sheet with adhesive was built, and the roll-hemming loss and surface wave coefficient were taken as the roll-hemming forming quality index to analysis and verify the validity of the numerical model. After that, the quality change between the first pass and the last pass and the key process parameters affecting quality were studied based on the orthogonal test method. Finally, the fitting relationship between roll-hemming forming quality and process parameters was established. The results show that the roll-hemming loss and the surface wave coefficient of the last pass are reduced compared with the first pass. The process parameters that affect the surface wave coefficient in descending order are flanging height, fillet radius, TCP-RTP value, and roller diameter. The process parameters that affect the roll-hemming loss in descending order are TCP-RTP value, fillet radius, flanging height, and roller diameter. The fitting relationship can support the prediction of roll-hemming forming quality of aluminum alloy sheet with adhesive.

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    Feasibility of Wave Measurement by Using a Sailing Buoy and the Artificial Neural Network Technique
    QIN Yichao, HUANG Limin, WANG Xiao, MA Xuewen, DUAN Wenyang, HAO Wei
    Journal of Shanghai Jiao Tong University    2022, 56 (4): 498-505.   DOI: 10.16183/j.cnki.jsjtu.2021.094
    Abstract1963)   HTML216)    PDF(pc) (7435KB)(508)       Save

    Ocean waves have adverse effects on the operation and safety of ships. Real-time and accurate onboard wave monitoring is essential for green smart ships and navigational safety. It is an important method to use ship motion to perform inversion of the information of encountering waves, which has many advantages such as low cost and high spatio-temporal resolution, and has attracted wide attention. An inversion model based on artificial neural network (ANN) is proposed to deal with the shortcomings of existing ship motion inversion ocean wave models. Taking the motion time history of the ship as the input and the wave elevation time history as the output, the artificial neural network is used to extract the motion features of the ship, and the linear function is input to perform wave surface time history inversion. To verify the feasibility and the accuracy of the inversion model, a ship model tank test is conducted. The results show that the proposed wave measurement method based on the artificial neural network can well achieve regular wave and irregular wave elevation time history inversion. Most of the statistical errors of regular wave inversion are less than 10% and the error of irregular wave inversion is about 10%. The method proposed provides an effective and feasible means for inversion of wave time information in ship motion.

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    A Method for Carbon Emission Measurement and a Carbon Reduction Path of Urban Power Sector
    HU Zhuangli, LUO Yichu, CAI Hang
    Journal of Shanghai Jiao Tong University    2024, 58 (1): 82-90.   DOI: 10.16183/j.cnki.jsjtu.2022.222
    Abstract1920)   HTML8)    PDF(pc) (1670KB)(219)       Save

    To measure and reduce carbon emissions in the urban power sector, a method for measuring carbon emissions in the urban power sector and a carbon reduction path are proposed. First, a carbon emission measurement model for the urban power sector is established based on the data of local power generation and net inward power. Then, carbon reduction measures for the urban power sector are proposed from the generation side, grid side, load side and energy storage side. After that, an evaluation model for the effect of the carbon reduction measures is established. Finally, taking a typical city F in the Pearl River Delta as an example, the proposed carbon emission calculation model is used to calculate the carbon emissions of power sector of the city, and the effectiveness of carbon reduction in 2030 carbon peak scenario of the city is evaluated based on the carbon reduction measures. The results show that the proposed model can accurately measure the carbon emissions of the urban power sector, and by utilizing carbon reduction measures, carbon emissions of the city can be reduced by at least 10.6 million tons in 2030.

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    Robust Evaluation Method of Integrated Energy System Based on Variable Step Simulation and Improved Entropy Weight Method
    FAN Hong, HE Jie, TIAN Shuxin
    Journal of Shanghai Jiao Tong University    2024, 58 (1): 59-68.   DOI: 10.16183/j.cnki.jsjtu.2022.186
    Abstract1917)   HTML6)    PDF(pc) (5076KB)(122)       Save

    As an important manifestation of the energy Internet, the integrated energy system improves the energy utilization rate. However, it also brings more risks due to the high coupling and the large difference in the response speed between the various systems. From the perspective of system security, it becomes crucial to accurately identify the weak links in the system and evaluate the robustness of the system. Therefore, a robustness evaluation method combining variable step size simulation and improved entropy weight method is proposed in the complex network environment. First, the structure of the integrated energy system is introduced and the coupling links of the system are further explained. Then, the robustness indicators including network damage degree and connectivity factor are proposed, and a variable step according to the difference of the response time of different systems is adopted. Based on the simulation results, an improved entropy weight method is proposed, and a more objective evaluation method is constructed. Finally, the superiority of the evaluation method is verified by a case study.

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    Comprehensive Evaluation of Key Technologies in Power Internet of Things Based on Comprehensive Similarity of Cloud Model
    CHEN Lianfu, ZHONG Haiwang, TAN Zhenfei, RUAN Guangchun
    Journal of Shanghai Jiao Tong University    2024, 58 (1): 19-29.   DOI: 10.16183/j.cnki.jsjtu.2022.420
    Abstract1870)   HTML13)    PDF(pc) (1954KB)(86)       Save

    Currently, the comprehensive evaluation of the application of key technologies in the power Internet of Things (PIoT) has the characteristics of a single evaluation object, and the traditional evaluation methods are not applicable. In order to comprehensively evaluate the technology maturity and operational effectiveness of PIoT projects, a comprehensive evaluation index for key technologies in PIoT is established to comprehensively consider the different development stages. According to the characteristics of application scenario, an evaluation model based on the comprehensive similarity of cloud model is proposed. By reforming the technique for order preference by similarity to an ideal solution (TOPSIS) method, a decision matrix for a single evaluation object is constructed, and the shape-distance comprehensive similarity of the cloud model is used as a measure to characterize the relative closeness of the TOPSIS method, and the accurate evaluation of a single object is realized. Finally, the proposed method is applied to assess a PIoT demonstration project. The results show that the proposed comprehensive evaluation index and evaluation method can objectively and comprehensively evaluate the comprehensive application effect of each key technology in the construction and operation stages of PIoT.

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    Design of a Virtual Assembly Gesture Library and Optimization of Ergonomics Evaluation
    GUO Jiawei, XU Zhijie, HE Qichang
    Journal of Shanghai Jiao Tong University    2022, 56 (2): 127-133.   DOI: 10.16183/j.cnki.jsjtu.2021.095
    Abstract1858)   HTML354)    PDF(pc) (7083KB)(604)       Save

    In view of the low efficient of virtual human upper limb simulation in the virtual assembly environment and the inaccurate evaluation of ergonomics, this paper analyzes hand assembly action, defines hand joint structure, arm and hand size, establishes a parametric assembly gesture model, and forms a gesture library. The fuzzy algorithm is used to improve the rapid upper limb assessment (RULA) method. The trapezoidal function is used to optimize the evaluation score when the joint angle is at the critical value. The final evaluation result is obtained through the rule base. Strain index(SI) is used to evaluate the risk of musculoskeletal operations such as hands and wrists, and the comprehensive score is weighted with fuzzy RULA evaluation. The ergonomics of the virtual hand assembly process is continuously evaluated to capture the risk posture in the assembly operation. Finally, the above methods are integrated based on the 3D Experience platform and verified by the assembly of mobile communication components.

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    Influence of Structural Pseudo-Static Components on Seismic Responses of Low-Medium Speed Maglev Vehicle-Bridge System
    HUANG Fenghua, CHENG Bin, TENG Nianguan
    Journal of Shanghai Jiao Tong University    2022, 56 (4): 486-497.   DOI: 10.16183/j.cnki.jsjtu.2020.381
    Abstract1856)   HTML192)    PDF(pc) (2108KB)(343)       Save

    Unlike the traditional seismic analysis on bridge engineering which mainly concerns the relative motion, the seismic analysis of vehicle-bridge system focuses more on the absolute motion of the vehicle system, where the pseudo-static components need to be considered. In order to study the effect of structural pseudo-static components on the seismic responses of low-medium speed maglev vehicle-bridge system, the discussion relying on a typical low-medium speed maglev line was implemented. Considering the vehicle-bridge coupling relationship based on the proportional integral derivative (PID) active suspension control, two dynamic models for the low-medium speed maglev vehicle-bridge system subjected to earthquake were relatively established in the relative coordinate and the absolute coordinate, and the seismic forces were correspondingly solved by employing the relative motion method and the direct solution method. A case study was subsequently conducted, where the effect of structural pseudo-static components on dynamic responses of the vehicle-bridge system, including the maglev gap, the vehicle system and the bridge was further analyzed. The results show that the influence of pseudo-static components on the dynamic responses of the vehicle system is quite significant. Ignoring the pseudo-static components could seriously undervalue the dynamic responses of the vehicle system, of which the difference could be as high as 447%. Compared to the vehicle system, the influence of pseudo-static components on the vertical and transversal displacement responses of the bridge is fairly limited. Therefore, it is suggested that the absolute displacement method which takes the pseudo-static components into account should be adopted to deal with the seismic excitation in the maglev vehicle-bridge system.

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    Reliability Index Calculation and Reserve Capacity Optimization Considering Multiple Uncertainties
    YE Lun, OUYANG Xu, YAO Jiangang, YANG Shengjie, YIN Jungang
    Journal of Shanghai Jiao Tong University    2024, 58 (1): 30-39.   DOI: 10.16183/j.cnki.jsjtu.2022.366
    Abstract1832)   HTML5)    PDF(pc) (1413KB)(113)       Save

    In power systems with a high proportion of renewable energy, to achieve coordinated optimal scheduling of source and load considering multiple uncertainties is an important issue in power system operation. Therefore, a probabilistic spinning reserve optimization model based on multiple scenarios is constructed. Multiple uncertain factors are considered in the model, such as wind power and solar power forecast errors, load forecast error and unscheduled generator outage. Renewable energy curtailment and load shedding are used as special reserve resources in the day-ahead security-constrained unit commitment (SCUC) to improve the economic operation efficiency. The calculations of reliability indexes, expected energy not served and expected energy curtailment, are simplified, and the inequality constraints related to these two indexes are reduced, which improves the computational performance of the model. The model optimizes the total expected cost considering multiple uncertainties. Case studies based on the IEEE-RTS demonstrate the effectiveness of the proposed model. The numerical results show that the improved calculation method of reliability indexes can effectively reduce the solution time of the SCUC model. The reserve optimization model can realize the dynamic allocation of the spinning reserve capacity of the system and improve economic operation of the system.

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    Analysis of 1-D Consolidation of Double-Layered Saturated Porous-Fissured Clay Foundation
    HU Yayuan, WANG Aqiang
    Journal of Shanghai Jiao Tong University    2022, 56 (4): 443-453.   DOI: 10.16183/j.cnki.jsjtu.2021.019
    Abstract1826)   HTML122)    PDF(pc) (2021KB)(356)       Save

    In order to study the one-dimensional (1-D) consolidation behavior of double-layered saturated porous-fissured clay foundation, the governing consolidation equations of saturated porous-fissured media were developed based on the mixture theory under the condition of one-dimensional complete confinement. The finite element program for 1-D consolidation of saturated porous-fissured clay was compiled by Fortran language, and the results of single-layered foundation research were used to verify the correctness of this model and program. The influences of compression modulus, permeability coefficient, and soil thickness on the consolidation behavior of double-layered saturated porous-fissured clay foundation were analyzed by using the finite element program. The results show that the consolidation rate of the foundation can be significantly accelerated by increasing the compression modulus and permeability coefficient of the softer topsoil, and the dissipation laws of excess pore water pressure and excess fissure water pressure were different. The dissipation of excess pore water pressure at the base of the foundation would lag behind that of excess fissure water pressure, and the lag would increase with the increase of the permeability coefficient of topsoil. For double-layered saturated porous-fissured clay foundation, improving the softer porous-fissured clay properties of the upper layer can better improve the consolidation behavior of the foundation.

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    Deflections of Adjacent Underground Tunnel Induced by Excavation Based on Kerr Foundation Model
    FENG Guohui, XU Xing, HOU Shilei, FAN Rundong, YANG Kaifang, GUAN Lingxiao, XU Changjie
    Journal of Shanghai Jiao Tong University    2022, 56 (4): 474-485.   DOI: 10.16183/j.cnki.jsjtu.2021.067
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    The soil unloading effect caused by the adjacent excavation will influence both the uplift and the deformation of the adjacent existing tunnel, and even interfere with the normal operation of the tunnel. A simplified calculation method for the longitudinal deformation of the underlying tunnel caused by foundation pit excavation is proposed. The tunnel is simplified into an infinitely long Euler-Bernoulli beam resting on a three-parameter Kerr foundation model. The difference method is combined with the boundary conditions at both ends of the tunnel to obtain the longitudinal deformation difference decomposition of the tunnel. The accuracy of the proposed method is proved by comparing it with the finite element simulation method and some cases study. Compared with the tunnel simplified as the Euler-Bernoulli beam which is placed upon the existing Pasternak foundation model, the Kerr foundation model has more advantages. As the elastic modulus of soil mass and the depth of tunnel axis increase, the longitudinal deflection and the inner force of the tunnel will decrease. The inner force of the tunnel will increase with the increment of the stiffness of the tunnel.

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    Comparative Analysis of Technical Standards for Offshore Wind Power via VSC-HVDC
    YU Hao, ZHANG Zhemeng, PENG Sui, ZHANG Zhiqiang, REN Wanxin, LI Canbing
    Journal of Shanghai Jiao Tong University    2022, 56 (4): 403-412.   DOI: 10.16183/j.cnki.jsjtu.2021.465
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    This paper introduces the current situation of domestic and foreign offshore wind power grid-connected via voltage source converter based high voltage direct current(VSC-HVDC) transmission standards, and selects representative standards of offshore wind power grid-connected via VSC-HVDC. It also compares the domestic and foreign offshore wind power grid in terms of power control, fault ride-through, power quality, stability, etc., and analyzes the development trend of offshore wind power grid-connected via VSC-HVDC standards. In order to promote the development of offshore wind power industry, it provides reasonable suggestions for the formulation and revision of Chinese offshore wind power grid-connected via VSC-HVDC standards.

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    Horizontal Dynamic Response of Pile Based on Layered Generalized Gibson Foundation
    QIU Jiekai, DING Zhaowei, SONG Chunyu, CHEN Longzhu
    Journal of Shanghai Jiao Tong University    2022, 56 (4): 431-442.   DOI: 10.16183/j.cnki.jsjtu.2020.382
    Abstract1809)   HTML147)    PDF(pc) (1931KB)(383)       Save

    In order to directly solve the horizontal dynamic response of a single pile under the condition that the shear modulus of the soil around the pile varies linearly with the depth, a method for solving the horizontal dynamic response of piles in nonhomogenous foundation is proposed based on the layered generalized Gibson foundation and the Adomian decomposition method. Compared with the initial parameter method and the transfer matrix method, the proposed method does not need to discretize the nonhomogeneous foundation. Compared with the numerical method, it has the advantages of low computational cost, high accuracy, and fast convergence speed. The correctness and rationality of this method are verified by comparing it with the calculation results of the layered method, the analytical method of homogeneous foundation, and the numerical method. The influence of boundary conditions on the pile bottom, soil parameters, and pile slenderness on the horizontal dynamic response of the pile is investigated. The result show that in nonhomogeneous foundation, the pile-soil elastic modulus ratio is an important factor affecting the horizontal dynamic response of pile. As the shear modulus of soil increases, the amplitude of horizontal displacement of the pile decreases, and the distribution tends to be gentle. In addition, compared with other parameters, Poisson’s ratio and damping ratio of soil have less influence on the horizontal dynamic response of pile.

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    Optimization Design of New Bionic Propeller
    WU Chunxiao, LU Yu, LIU Shewen, GU Zhuhao, SHAO Siyu, SHAO Wu, LI Chuang
    Journal of Shanghai Jiao Tong University    2023, 57 (11): 1421-1431.   DOI: 10.16183/j.cnki.jsjtu.2022.174
    Abstract1678)   HTML22)    PDF(pc) (10709KB)(318)       Save

    A novel method for optimal design of hydrodynamic performance of bionic propeller with a deformable leading edge is proposed. Based on the bionics principle and method of parameterized modeling, the fore-fin concave-convex structure of humpback whales is applied to the propeller leading edge, the leading edge in the propeller to meet flow region according to the exponential decay curve and the standard sine curve smooth leading edge for similar humpback fins protuberant structure of concave and convex deformation, and the leading edge of concave and convex bionic propeller. The hydrodynamic performance, the cavitation performance, and the noise performance of the exponential decay bionic propeller and the sinusoidal function bionic propeller were simulated respectively. The propeller with a better performance is selected, and the simulation based design (SBD) technology is introduced into the optimization design of the new bionic propeller. The parameters controlling the shape of the exponential attenuation curve of the guide edge deformation are taken as optimization design variables, the torque of the parent propeller is taken as the constraint condition, the open water efficiency is selected as the objective function, and the optimization algorithm of Sobol and T-Search is adopted. A bionic propeller optimization system based on the exponential decay curve is constructed. The results show that the application of the concave and convex structure of the humpback whale fore-fin to the guide edge of the propeller improves the cavitation performance and noise performance of the propeller, but the improvement of the open water performance of the propeller is not particularly significant. It is verified that the hydrodynamic performance optimization design method of the bionic propeller established in this paper is effective and reliable, which provides a certain theoretical basis and technical guidance for the performance numerical calculation and configuration optimization design of the bionic propeller.

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    Development Pathway of China’s Clean Electricity Under Carbon Peaking and Carbon Neutrality Goals
    HUANG Qiang, GUO Yi, JIANG Jianhua, MING Bo
    Journal of Shanghai Jiao Tong University    2021, 55 (12): 1499-1509.   DOI: 10.16183/j.cnki.jsjtu.2021.272
    Abstract1659)   HTML523)    PDF(pc) (1849KB)(980)       Save

    Nowadays, the third energy revolution has taken place. Many developed countries have formulated clean energy development strategies and announced the time for phasing out thermal and nuclear power to reduce carbon emissions. Meanwhile, China has made a commitment to the world that the carbon emissions of China will peak before 2030, and the carbon neutrality will be achieved before 2060. Therefore, it is of great significance to study the development pathway of clean electricity of China. The reserves and characteristics of clean energy such as hydro, wind, and solar in China are analyzed. The medium and long-term power demand of China is projected, and the power system structure in 2030 and 2050 are respectively estimated based on the electric power and energy balance equations. In addition, the trend of carbon emissions is also analyzed. Some suggestions are proposed to guide the development of China’s clean electricity. The results indicate that the “carbon peaking” of China’s power system would arrive in 2027, and the clean electricity of China is projected to exceed 50% of the total energy production in 2030. Thermal and nuclear power can be replaced by clean electricity such as hydro, wind, and solar energy in 2050, the power industry will achieve “zero CO2 emission”, and the transformation of the green power system will be achieved in response to carbon peaking and carbon neutrality goals.

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