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  • ZHOU Xiao, LI Xiaodong, LENG Yu
    Journal of Shanghai Ship and Shipping Research Institute. 2024, 47(4): 81-86.
    In response to the need of systematic research on carbon emission management approaches for enterprises,this paper reviews the current situation and future development trend of carbon emission management in several key industries such as shipping industry, power industry, steel industry and aviation industry. The critical problems of existing carbon emission management in these enterprises are analyzed. 7 key critical problems limiting the efficient carbon emission management are identified. Top-level planning, data standardization system and carbon emission factor accounting are considered the most important 3 of them. 8 key things for carbon emission management are brought out. They cover developing strategy and roadmap for low-carbon transformation, improving carbon emission factor accounting system, developing low-carbon technology, and establishing carbon information publication management mechanism.
  • LU Yuexin, LIU Yingliang, ZHOU Yilong, JI Sheng
    Journal of Shanghai Ship and Shipping Research Institute. 2024, 47(4): 1-10.
    In propeller cavitation pulsation pressure testing, the stability of cavitation significantly affects the time domain characteristics of the induced pulsation pressure. This stability also determines the accuracy of predicted cavitation pulsation pressure. Three processing methods are compared: ordinary FFT (Fast Fourier Transform); averaging the signal in the time domain before Fourier transform (Time-domain averaged FFT); averaging the signal in the frequency domain after Fourier transform (Frequency-domain averaged FFT). The calculations were conducted to analyze the pulse pressure signals induced by stable and unstable vacuoles. The results indicate that the Time-domain averaged FFT and the Frequency-domain averaged FFT can eliminate the interference of random factors and produce consistent prediction results when compared to the direct FFT method. However, the Time-domain averaged FFT method is not applicable for unstable cavitation. In that case, the Frequency-domain averaged FFT method can more accurately predict the pulse pressure amplitude.
  • FENG Liang, ZHAO Ke, HUANG Zhenping, MU Yadi
    Journal of Shanghai Ship and Shipping Research Institute. 2024, 47(4): 11-18.
    The AnyLogic simulation platform is used to study the operation of shipping industry and find the way of achieving higher efficiency and lower operating costs. A complex shipping network simulation model is constructed by combining ABM (Agent-Based Model) and DES (Discrete Event Simulation) methods. Ship’s departure, navigation, loading and unloading at the port, and fuel filling are modeled. Simulation experiments reveal that transportation costs and impacts of environmental factors can be significantly reduced by optimizing speed and fuel strategies. The simulation model can be used to simulate and respond to market fluctuations and emergencies, and improve the emergency response ability and market adaptability of shipping companies.
  • QIAN Sheng
    Journal of Shanghai Ship and Shipping Research Institute. 2024, 47(4): 59-71.
    In order to prevent major safety risks in the operation of the Xupu Bridge and improve the level of structural safety assurance, it is proposed to establish a Xupu Bridge structural health monitoring system. The sensors as the basic data source for entire system are to be deployed according to the structural characteristics of Xupu Bridge. The sensor layout is carefully optimized to achieve all-weather and all-round understanding of the bridge operating environment and structural conditions, ultimately ensuring the safe and reliable operation of the bridge structure throughout its entire design life cycle.
  • XU Wenyu, WANG Nan
    Journal of Shanghai Ship and Shipping Research Institute. 2024, 47(4): 39-43.
    In the context of carbon emission reduction, to respond the regulatory requirements for carbon emissions from operating ships, a mathematical model of carbon emissions for operating ships is established. The operation of a container ship is studied based on the operational data of the container ship. The carbon intensity and economics of feasible emission reduction measures are analyzed. The result shows that in the short term, the carbon intensity rating limit for the next ten years can be met by speed management and existing emission reduction technologies, but overuse of speed reduction will go against the operating costs. In the medium to long term, the use of biofuel blends and improving fleet management may be the solution to meet the carbon intensity requirements for existing ships over their operating cycles.
  • YAO Tao
    Journal of Shanghai Ship and Shipping Research Institute. 2024, 47(4): 44-49.
    The provision of Ships Entry and Departure issued by China Port authority requires a ship to report its entry/departure plan in specified time. In order to detect ships who fail to follow the regulations a technical solution is devised. The streaming data processing engine Apache Flink is used to check ships’ berthing/unberthing operation against the ships’ reporting data and find the ships who did not report its plan in specified time. An alarm will be announced if such a ship is found. The design has been used in a maritime information platform and worked well.
  • WANG Hongxing, LIU Wei, ZHANG Danrui
    Journal of Shanghai Ship and Shipping Research Institute. 2024, 47(4): 19-29.
    A source-storage cooperative control strategy is developed to address the power distribution and operation stability problem caused by equipment grid-tie/off-grid operation in marine DC power systems and to ensure the stable operation of the power system under various operating conditions. A mathematical model is built based on MATLAB/Simulink. The mathematical model runs in real time on the RT-LAB simulation platform. The control strategy is verified in multiple working conditions through online parameter adjustment function. The simulation results show that the proposed source-storage control strategy can effectively improve the power distribution efficiency and operation stability of the Marine DC power system, and ensure the stable operation of the power system under various working conditions.
  • PENG Dengchao, WANG Yanguo
    Journal of Shanghai Ship and Shipping Research Institute. 2024, 47(4): 30-38.
    In order to enhance the stability of lithium battery packs operating in parallel on a ship’s DC power grid, the system is mathematically modeled and the control algorithm is developed. A Simulink model of parallel “Energy Storage-DC/DC-DC Bus.” is built to simulate different output characteristics of energy storage modules. An improved current equalization control algorithm based on voltage-current dual-loop control is devised. The algorithm calculates the mean square deviation of voltage-current simulation data and analyzes the current equalization accuracy. Experimental results demonstrate that this strategy effectively improves the voltage stability of the ship’s DC bus, reduces current imbalance, and enhances overall system performance and safety.
  • LI Yangguang
    Journal of Shanghai Ship and Shipping Research Institute. 2024, 47(4): 50-58.
    In response to the enterprise managements’ eagerness for accurate, rigorous, fast financial monthly reports and efficiently submit them , a financial fast monthly report submission platform based on SAP BW (SAP Business Warehouse) is developed. The existing problems in the issuance, adjustment, and submission of reports are analyzed and the overall framework, design ideas, and solutions for report presentation and the submission platform of the reports are elaborated. The application of the design proves that the financial quick monthly report solution based on SAP BW can not only meet the accuracy of financial statements, but also balance the rigor and speed of report submission. It also has good operability and promotability.
  • QIAO Zhaochao, GU Renji
    Journal of Shanghai Ship and Shipping Research Institute. 2024, 47(4): 72-80.
    Environmental supervision during the construction of a new quay berth project plays an irreplaceable role for reducing and avoiding environmental damage, which is beneficial to the sustainable economic development and environment of the region around the site. The practical environmental supervision work during the construction of 5# and 6# Berths in Shihu Operating District of Quanzhou Portis is presented. The environmental supervision work was guided by the experiences gained in a number of environmental supervision projects. According to the specific situation of the project and the characteristics of the environment the supervision, beside typical environment protection monitoring tasks, paid special attention to things, such as dust prevention and control, marine ecological monitoring, caring of aquatic species enhancement and releasing.
  • GUO Lei, CHENG Jinxing
    Journal of Shanghai Ship and Shipping Research Institute. 2025, 48(1): 54-61.
    In order to effectively handle the network security risks faced by ships in the process of digital transformation and Intellectualization of shipping, the path of ship network security construction in the text of new development pattern is studied. Current situation of ship network security at home and abroad is elaborate and main risks in ship network security is sort out. A path for ship network security construction to follow is designed to improve the level of ship network security protection. The stable operation of ocean-going ships is to be ensured through the arrangement.
  • JIANG Chenji, DONG Shengli, HAN Bing
    Journal of Shanghai Ship and Shipping Research Institute. 2024, 47(5): 22-29.
    In order to improve system development efficiency, the software is developed based on theBrowser/Server (B/S) architecture and the principle of front-end and back-end separation. The technical framework of the system software is decided. The main front-end interface and back-end functional modules are planned. The complete intelligent engine room system software based on principle of front-end and back-end separation is developed. The system software has been proved to be reliable and stable.
  • ZHANG Hongming, QIAO Jipan, JI Sheng, ZHANG Yanfei
    Journal of Shanghai Ship and Shipping Research Institute. 2025, 48(1): 13-17.
    In order to reduce the compliance cost pressure caused by the EU (European Union) issued FuelEU Maritime regulations, this paper studies the impact of these regulations on shipping costs with emphasis on the expiration of the RWD (Reward) coefficient. An 8 500 TEU container ship using EU ports is taken as an example to show the compliance costs before and after the RWD coefficient expiration and the implementation of the RFNBO (Renewable Fuels of Non-Biological Origin) sub targets. The analysis shows that from year 2034, when the RWD coefficient expiring and the RFNBO sub targets coming into force, this container ship will fail to meet the requirements for the carbon balance and RFNBO sub targets, thus facing double fine. The analysis suggests that shipping industry should increase the use of RFNBO fuel to reduce the economic burden caused by increased compliance costs.
  • LI Rongzong, ZHANG Chaoqun, YANG Shaoyuan
    Journal of Shanghai Ship and Shipping Research Institute. 2025, 48(1): 1-7.
    In order to improve the active ship motion attitude compensation control capability, a ship roll motion prediction model based on LSTM (Long Short-Term Memory) model is introduced helping to address the problems of existing ship roll motion prediction models which do not provide sufficient accuracy and effectiveness in complex environments. The model is trained with roll motion data collected from a research and training dual-use ship in operation on the sea. The root mean square error is used as the loss function, and the Adam optimizer is used for weight optimization. The new model is tested on ships navigating on the sea, and the results are compared with the prediction results given by the ARIMA (Autoregressive Integrated Moving Average) model to verify the model in complex ship navigation conditions. The research results indicate that the LSTM-based ship roll motion prediction model can better capture the nonlinear and /or non-stationary characteristics of ship roll data and provide more accurate prediction results.
  • HU Haofan, GUO Xiaofeng
    Journal of Shanghai Ship and Shipping Research Institute. 2025, 48(1): 8-12.
    In order to better cope with the complex and changing sea ice environment and limited emergency rescue capabilities faced by ships navigating in the Arctic shipping route, and to enhance their risk prevention and control capabilities in ice navigation, research on ship navigation risk identification and prevention in the Northeast Arctic shipping route is carried out. The relevant regulations and navigation facilities and equipment for ships in the Arctic shipping route are analyzed, environmental risk factors from the aspects of sea ice environment, hydro meteorological conditions, and geographical environment are identified, and risk control measures for ships navigating in the ice zone of the Arctic shipping route are proposed. The research suggests that the risk factors faced by ships navigating the Arctic Northeast Passage mainly include complex sea ice, poor visibility, low temperatures, strong winds and waves, variable ocean currents, and inaccurate nautical chart information. From the perspective of risk prevention, 21 self-examination items for ships before entering the ice zone are proposed. From the perspective of risk control during navigation in the ice zone, 10 risk prevention measures are proposed to enhance the safety guarantee capability of ships navigating in the ice zone of the Northeast Passage.
  • LIN Zhexian
    Journal of Shanghai Ship and Shipping Research Institute. 2024, 47(6): 36-42.
    In order to augment the traffic perception capability of the ferry terminal and improve the overall digitalization level, a Transformer-MLP(Multi Layer Perceptron)-based method for short-term prediction of ferry terminal passenger flow is introduced, The design is capable of predicting the passenger flow in 4 predefined time periods of following day. The prediction method performs ETL (Extract-Transform-Load) and get passenger flow data in the form of time series from ferry business data. A combined time series model PatchTSTiDE is built based on the collected time series data transformed from ferry business data by means of the time series forecasting toolkit NeuralForecast. Tests show that, Compared with TiDE (Time-Series Dense Encoder) and PatchTST, the developed model is about 4.44% and 30.59% better in MAE (Mean Absolute Error) respectively.
  • HE Yixuan, AI Wanzheng, HE Fangchi
    Journal of Shanghai Ship and Shipping Research Institute. 2025, 48(1): 18-24.
    A type of bulk carrier is investigated and studied empirically and theoretically to find the causes of high water drag and low efficiency. Measures to reduce the drag force particularly for the interested type of bulk carriers are devised. The improvement scheme covers using high-efficiency anti fouling paint, optimizing bow shape, and using high-efficiency propellers. A ship is retrofitted according to suggested scheme and tested. The test results proved the effectiveness of the measures.
  • ZHU Xiaoqiang, SHI Yunyu, DOU Peng, XU Feng
    Journal of Shanghai Ship and Shipping Research Institute. 2025, 48(1): 40-47.
    In order to deal with the methanol leakage in the fuel tank of a methanol dual fuel ship, computational fluid dynamics software is used to numerically simulate the ventilation performance of the fuel tank with methanol leakage. A 16 000 TEU methanol dual fuel container ship is taken, as an example, to demonstrate the process. The objective is to examine the leakage of methanol gas in the cabin and study the variation of the time required for indoor air to meet personnel safety standards with the number of pipe openings and exhaust speed. The research shows that reasonable openings in pipelines can significantly improve the ventilation of fuel tanks. It is recommended that the fan speed be increased by 50% while having above mentioned openings, which can keep the safety time under 300 seconds and reduce electricity consumption.
  • XIAO Changyun, WANG Bingde, WANG Shengzheng
    Journal of Shanghai Ship and Shipping Research Institute. 2025, 48(1): 25-33.
    In response to the new demands of ship intelligence for information processing, integration, analysis, and interactive interface design, a comprehensive information display system for ship intelligent driving is developed. Through an in-depth analysis of the information needs in ship driver-machine interaction, and in accordance with the Intelligent Ship Specification (2024) and the IMO (International Maritime Organization) display performance requirements, an information classification method for ship intelligent driving is proposed. Different navigation information expression methods are designed, and a comprehensive navigation information display system is developed. The system was demonstrated and applied on intelligent driving ships. The operation shows that it has comprehensive, standardized, intuitive, and convenient characteristics in information fusion and expression, which helps to improve the safety and efficiency of ship navigation.
  • FANG Shuo, BAI Nan, SHI Tianrun, CUI Baojun
    Journal of Shanghai Ship and Shipping Research Institute. 2025, 48(1): 62-74.
    In order to reduce the impact of vibration and structural noise generated by subway vehicle operation on environmentally sensitive buildings in the property projects above the subway depot, a study is conducted on the vibration effects at different areas of the depot. A property development project above a subway depot in a city in East China is selected for vibration impact testing, and to study the vibration characteristics at different areas such as test lines, entrance and exit lines, warehouse lines, and throat areas. The research results indicate that compared to the throat area and the testing line area, the total vibration level of the warehouse line is relatively small; In the throat area, the average Z-vibration level when a train goes over the frog is 29.4 dB higher than that when it is over other part of the rail; At a given test section, the maximum Z-vibration level gradually decreases in the order of the rail, track bed, and structural wall.
  • GAO Zehua, LI Liang
    Journal of Shanghai Ship and Shipping Research Institute. 2024, 47(5): 38-44.
    In order to accurately determine the human error factors that causes pilotage accidents and take effective measures to prevent similar accidents from occurring, the Cognitive Reliability and Error Analysis Method (CREAM) is used to analyze pilotage accidents. Based on the retrospective analysis function in the CREAM, a pilotage accident retrospective model is established, and three types of human error factor relationship tables (the Genotypes Tables, General and Specific Antecedent Tables, Error Mode Antecedent Table) are constructed. Based on these tables, the causes of pilotage accidents are traced. With a typical grounding accident as the example, the method is used to trace the human factors that lead to the grounding, and the results is compared with the accident analysis results in the existing accident investigation report to verify the effectiveness of the method. Suggestions for improving the safety of ship pilotage are put forward, including strengthening the education and training of pilots, improving the reliability of pilotage facilities, and strictly implementing regulations, etc.
  • WANG Jian, WANG Yanguo, TENG Wenqing, ZHANG Danrui
    Journal of Shanghai Ship and Shipping Research Institute. 2024, 47(6): 20-28.
    The safety of ammonia fuel transmission is a critical issue for application of the clean energy source. This paper examines fuel transmission performance of a newly developed marine ammonia fuel system through simulation to verify the design. Based on the physical characteristics of ammonia fuel, the mechanism model of the ammonia fuel transmission system is built, and the effectiveness of the model is verified. The real time simulation is performed with the transmission system model to test and verify the performance of the controller of the system. The simulation operation is effective in system performance testing, not only for normal working conditions but also for extreme working conditions.
  • GAO Xuan, GAO Yuling, CHEN Weimin, DU Yunlong, SI Nan
    Journal of Shanghai Ship and Shipping Research Institute. 2024, 47(5): 8-15.
    A ship with high block coefficient is studied to determine the influential ship type characteristic parameters in designing the stern form of full-formed ships. The stern form is modeled and automatically varied under the constraint of drainage volume through semi-parametric control by means of software CAESES and corresponding resistance performance and wake of the ship type are calculated by means of software SHIPFLOW. The optimization strategy is designed based on the combination of Sobol algorithm and Nelder Mead Simplex algorithm, and the regression analysis is performed to examine the resistance and wake non-uniformity of different ship forms. The Performances for the form variations are calculated and verified by software Star CCM+. The findings are as follows: the fullness of the stern form at the maximum contrary flexure position above the target stern axis and the shape of the stern transom have significant impact on the wake. The optimization achieved about 2% reduction of the effective power and 6.4% reduction of the wake non-uniformity compared with the original design.
  • LI Jianpeng, LIU Jinchun, LI Weiqiang
    Journal of Shanghai Ship and Shipping Research Institute. 2024, 47(5): 1-7.
    The commercial software SHIPFLOW MOTIONS based on potential flow theory is used to simulate the motion of a surveying vessel in waves. The physical characteristics of ship motion in regular waves are calculated using three-dimensional, time-domain, and fully nonlinear boundary element methods, The numerical calculation results are examined against the model test results. The research shows that the numerical calculation results of heave and pitch motion fit well with the model test results. For ship's resistance increase in waves, the maximum deviation between the RAO numerical calculation results and the model test results is about 13%, which is significantly more accurate than that the three-dimensional frequency-domain linear potential flow theory can produce. In addition, to verify the nonlinear problem-solving ability of the software, it is directly used to simulate the motion of the ship in irregular waves. The results shows that the deviation between the wave drag calculation results and the experimental results is about 7%, which implies that using the potential flow method to solve problems of ships in complex flow field is feasible.
  • LIN Yujin, ZHU Shaosong, LI Xiaodong, ZHOU Xiao, LENG Yu
    Journal of Shanghai Ship and Shipping Research Institute. 2024, 47(6): 61-68.
    Based on the guidelines for compiling air pollutant and greenhouse gas emission inventories, a comprehensive emission inventory for typical coastal container terminals is established. By integrating on-site investigation data, emission factors, and activity level data, emissions during four operational stages (quayside loading/unloading, yard loading/unloading, horizontal transportation, auxiliary and ancillary production) in 2023 are estimated. The Monte Carlo simulation is performed to quantify uncertainties. The research shows that NOx and CO are the main air pollutants at the terminals, with container trucks and stackers as the primary sources of air pollutants. Indirect emissions from electricity consumption contribute the most to carbon emissions, with container trucks, yard cranes, and shore bridge being the main sources, accounting for 25.57%, 23.78%, and 23.43% respectively. The uncertainty of the inventory ranges from -67% to 139%. This comprehensive inventory reflects the characteristics of air pollutant and carbon dioxide emissions at coastal container terminals, providing scientific support for air pollution control and carbon emission reduction.
  • ZHENG Min, SHI Tianrun
    Journal of Shanghai Ship and Shipping Research Institute. 2024, 47(5): 70-76.
    The plant extract deodorization technology is introduced to reduce the impact of odorous substances released during the loading, unloading, and compression process in municipal refuse transfer stations on the surrounding environment. By comparing and analyzing, the deodorization effects of plant extract deodorization under different experimental conditions are determined. The research shows that the deodorizing effect of plant extracts is dependent on their active ingredients and concentration ratios and influenced by factors such as the reaction time between plant extracts and exhaust gases, the deodorizing process and so on. In practical applications, it is recommended to optimize the plant extract deodorization formula for particular odor components, improve the plant liquid deodorization process, and extend the time for plant extracts-exhaust gas reaction, so as to improve the deodorization efficiency of plant liquid.
  • XING Lei, YANG Fan, YIN Xiaojun
    Journal of Shanghai Ship and Shipping Research Institute. 2024, 47(6): 1-5.
    The scale effect in model tests and numerical simulations of a large bulk carrier with combined energy-saving devices is studied. The energy-saving performance achieved by the devices is tested and calculated in two different model scales respectively. The test data are compared with the calculation results. The comparison shows that the tests with larger model scale is better in predicting performance improvement and the trends of propulsive performance parameter change caused by the energy-saving devices. From the perspective of engineering application, it is recommended that, within the reasonable range of test conditions, large-scale ship models should be used for towing tank tests of ships equipped with energy-saving devices.
  • LI Changliang, GUO Jian
    Journal of Shanghai Ship and Shipping Research Institute. 2024, 47(6): 49-54.
    To effectively predict congestion at highway toll stations and solve it, a digital twin solution to predicting congestion happening at highway toll stations based on random forest model is introduced. This solution mainly includes the following functional modules: traffic scene construction; real-time data collection; congestion analysis and prediction; toll station intervention; and visualization display. It collects traffic information through integrated sensing devices such as door frames, vehicle inspectors, and millimeter wave radar. It uses the Unity3D platform to create high-precision 3D models of toll stations and uses CART (Classification and Regression Tree) algorithm to construct a random forest model for traffic flow prediction. Research shows that this scheme can help alleviate congestion at toll stations, improve the efficiency of highway operation and management, and improve the feelings of drivers and passengers.
  • XIAO Wuhua, TANG Shaohua, ZHUANG Haoran
    Journal of Shanghai Ship and Shipping Research Institute. 2025, 48(1): 48-53.
    The fault tree investigation and positioning are carried out in the troubleshooting of the PT1000 sensor module. The remedy is proposed. The principle of PT1000 acquisition circuit is elaborated; the causes of connection faults seen from external terminals on the module are listed and a wiring improvement by introducing a junction box between sensor input pins and external cable terminals is proposed. The practical application results show that the improvement solved the problem of large step temperature measurement jumping.
  • LU Zigang, ZHENG Liangliang, JIN Zhennan
    Journal of Shanghai Ship and Shipping Research Institute. 2025, 48(1): 34-39.
    A hull safety monitoring system is designed for ensuring ice navigation safety of ships in polar area. The functional requirements for the system are analyzed and the system particularly for a 68 000 ton multi-purpose pulp ship is designed to illustrate the overall architecture design, equipment layout, and practical application of the system. The practical application of the system shows that the system can evaluate the overall strength of the ship in real time and reduce the risk of ship structural damage during navigation in ice areas by collecting data, such as, ship structural stress, ship motion status, and meteorological and sea conditions.
  • YANG Jing, ZHANG Lin, DONG Zhiqiang
    Journal of Shanghai Ship and Shipping Research Institute. 2024, 47(6): 29-35.
    The electric power system for a multi-purpose heavy lift vessel needs special design effort because it has to ensure the operation of the cranes onboard, which cause great surge loading. This paper explores the impact of cranes on the design of power plants on multi-purpose heavy lift vessels, focusing on the power station capacity configuration, the power management, reverse power handling, and the selection of cable and protection devices. The power requirements of the cranes are determined based on demand coefficients and probability calculation to ensure that the generator capacity meets actual needs. The design includes heavy load request and power limitation functions in the power management system to ensure safe operation. Various solutions for reverse power handling are investigated, including reverse power absorption resistors, power limitation, and battery absorption.
  • XIAO Changyun, WANG Zichuang, LIU Hongyu, HAN Bing, CHEN Xinqiang
    Journal of Shanghai Ship and Shipping Research Institute. 2024, 47(6): 14-19.
    In order to enhance the perception ability of ships to the surrounding environment under poor visibility conditions such as foggy weather, a maritime image dehazing method based on the cycle generative adversarial network is introduced. It enhances the stability of dehazing effects, avoiding excessive image deformation and the loss of important features by introducing cycle consistency loss and identity loss. Experimental validation is conducted on both simulated and real foggy maritime images, and then compared with mainstream dehazing methods. The results demonstrates that our method outperforms others in terms ofPSNR (Peak Signal-to-Noise Ratio), structural similarity, and color difference. An average PSNR of 21.92 dB, surpassing traditional dehazing methods by at least 8.79 dB, is achieved. It is seen that the fog is effectively removed from images, and the details and texture information are restored.
  • ZHU Shaosong, HAN Zhuocheng
    Journal of Shanghai Ship and Shipping Research Institute. 2024, 47(5): 45-55.
    To achieve effective detection of safety helmet/working clothe targets from a work site image, an improved YOLOv5_6.0 small object detection algorithm is developed. Detecting helmet/working clothe targets has been challenging because they are small in size and similar in color, and yet, densely distributed. The bounding box regression loss function of the YOLOv5_6.0 algorithm is modified for optimizing the learning effect about dense small target feature information; One additional feature extraction layer is inserted to improve the small target detection performance; A Global Attention Mechanism (GAM) is introduced into the backbone to enhance the overall detection performance; A two-stage YOLOv5_6.0 small structure algorithm for confirming safety helmet/working clothe targets is integrated. The developed algorithm is used to process the images of shipping scenario for verification. The results show that the improved algorithm can achieve the average precision values of 97% for safety helmet detection and 87% for working clothe detection, an improvement of 5.5% and 5.3% respectively, compared to the original YOLOv5_6.0 algorithm.
  • ZHU Xiaoqiang, SHI Yunyu, DOU Peng, XU Feng
    Journal of Shanghai Ship and Shipping Research Institute. 2024, 47(5): 30-37.
    Based on the Computational Fluid Dynamics (CFD) software Star CCM+, a numerical simulation of ventilation of the pump compartment of a methanol-fueled 16 000 TEU ship is carried out. The volume change law of leaked methanol is derived by Volume Of Fluid (VOF), and the time required for the air in the pump compartment to reach the safety threshold at different jet velocities is studied. The research results show that with the existing ventilation system on the ship, the air in the pump compartment can reach the methanol safe threshold of 200 mg/L within 114.74 s. The ventilation effect is best when the jet velocity is 0.5 m/s, which shortens the time required for ventilation to meet the standard by 2%. When the jet velocity is too high, it will cause flow field disturbance, and some methanol gas will be blown into dead spaces and, hence, lower the ventilation effectiveness.
  • WANG Qiaoyan, LI Xiaodong, WANG Yachen, QIU Xianfeng
    Journal of Shanghai Ship and Shipping Research Institute. 2024, 47(5): 63-69.
    The indoor secondary structural noise prediction method proposed in the environmental impact assessment guidelines has left several key parameters undefined, hence the prediction results with the method has quite often been found unsatisfactorily deviating from actual measurement results. This paper theoretically analyzes the on-site measurement data (indoor vibration acceleration, vibration velocity, and secondary structural noise) from the buildings along the underground railways in Shanghai, Suzhou and Guangzhou, and devises a reference data looking-up-based method to supplement the guideline and improve the method. A set of actual measurement data for typical scenarios, including Z-axes vibration level, vibration velocity level, and structural noise, is collected and recorded. Looking-up the data set and finding the data associated with interested scenario, one can get au usable prediction. Practical application shows that 81% of prediction achieved 3 dB accuracy or better. As a comparison, for the prediction based on vibration level measurement, the number is 86%. In the circumstances of measuring vibration impractical, reference looking-up method is a reasonable alternative measure.
  • HAN Li
    Journal of Shanghai Ship and Shipping Research Institute. 2024, 47(6): 55-60.
    The environmental impact assessment project for reconstruction and expansion of expressway in Guangdong Province is presented. The acoustic environment quality of sensitive buildings along the expressway was measured and the noise impact after highway expansion was predicted. The noise reduction effects of four different forms of sound barriers, including vertical sound barriers, bent sound barriers, semi closed sound barriers, and fully closed sound barriers were analyzed. Low noise pavement, and speed limit setting were investigated. Based on the requirements of relevant laws, regulations, and technical policies, a comprehensive noise reduction plan was devised for the entire area affected by the project, including speed limit setting, low noise pavement, and multiple forms of sound barriers. This paper also suggests that big data technology should be introduced to highway noise prevention design to address the problems of updating lag and narrow valid parameter value of the current formula for predicting the intensity of expressway noise sources; Comprehensive information platform should be developed to collect wider range of data, such as road traffic flow, vehicle type ratio, and driving speed of each vehicle type and support the environment projects.
  • ZHANG Chaoqun, ZHANG Fan, LUO Weiqiang, ZHOU Lei
    Journal of Shanghai Ship and Shipping Research Institute. 2024, 47(5): 16-21.
    In order to improve the accuracy of prediction of wind speed and direction at sea the application of Auto-Regressive (AR) models is studied. The autocorrelation of the wind data time series is examined before AR processing. The Prediction of wind vector is conducted with Auto-Regressive Integrated Moving Average (ARIMA) model and the Vector Auto-Regressive (VAR) model separately and the results are examined. The experimental results show that 34.17% of the VAR model prediction results fall within the error range, while this number for ARIMA model reaches 61.25%.
  • LI Pengcheng
    Journal of Shanghai Ship and Shipping Research Institute. 2024, 47(6): 43-48.
    To continually Improve the maintenance timeliness for traffic mechanical and electrical equipment has been one of the major interests of traffic management departments. A Logistic regression model is built based on the related maintenance work order records kept in Shanghai. The cases that did not satisfy the system operators in terms of maintenance time are studied and the causes are analyzed. The analysis indicates that maintenance timeliness is strongly dependent on the following factors: the equipment type, the equipment location and trouble happening season. The camera equipment and the equipment for license plate recognition, information board are found to need more maintenance time. The equipment installed at the outer ring highway needs extra time. Besides, February, June and July are the higher fault rate months. The following improvement measures are suggested: to enhance the maintenance standard for key equipment; to set up operation and maintenance sub-centers at the outer ring highway; to increase the maintenance force in bad weather and holidays.
  • LIANG Jianxin, JI Hongyuan
    Journal of Shanghai Ship and Shipping Research Institute. 2024, 47(6): 6-13.
    Addressing the potential safety issues of hull structure and docking blocks during the strength test of large container ships in dock, this paper uses FEA (Finite Element Analysis) to simulate the process and verify the safety of hull structure. A suitable simulation method for docking blocks achieving both high FEA calculation efficiency and good reaction force calculation accuracy are introduced. An optimized scheme of docking block arrangement is devised. The fact is that the arrangement of docking blokes has been designed for ensuring the safety of ship construction in dock. Further requirements for in-dock strength test demands arrangement adjustment. The research shows that the knowledge on the distribution of reaction forces from the docking blocks can be the guide for the docking block arrangement adjustment, keeping it partial in range and minimum in quantity.
  • WANG Junxiang
    Journal of Shanghai Ship and Shipping Research Institute. 2024, 47(5): 56-62.
    This paper focuses on how to build a set of data streaming and aggregation technologies suitable for large group enterprises to store data towards objects in a hybrid multi cloud scenario, providing business side secure access and diverse source data interaction scenarios in the form of unified object storage PaaS services; This method adopts the cloud native S3 protocol to redefine the encapsulation, parsing, and forwarding control of heterogeneous object storage services, achieving data access interaction, replication migration, customized data layering, aggregation, merging, and loading of object storage in mixed heterogeneous scenarios through unified service scheduling. This method has been applied in the cross-border container rental application scenario of a large shipping group enterprise, and the results have shown that it can efficiently achieve secure, flexible, and elastic data unified interaction capabilities in the business scenario of mixed heterogeneous object storage.