In view of the fact that the current R&D level of mobile microreactor cannot meet the requirements of the GB11806-2019"Regulations for the Safe Transport of Radioactive Materials",the work aims to study the transportation safety of mobile microreactor by means of risk assessment.The risk assessment mainly included calculating the probability and consequences of extreme accidents encountered by the mobile microreactor during transportation,and the types of accidents that the mobile microreactor might encounter during transportation were sorted out according to the relevant requirements of 10CFR71 and §12 of the United States.The collision with the tanker truck with the most serious accident consequences was taken as the extreme hypothetical accident and the accident consequences of the mobile microreactor with a hypothetical heat power of 20 MWt under a hypothetical accident were calculated by the method of five-factor formula.The hypothetical accident probability of the mobile microreactor was 9.7×10-6/year under the condition of annual transportation,and the irradiation dose to the workers under the hypothetical accident after the microreactor was cooled for one year was 810 mSv.After 5 years of cooling,the radiation dose to the workers under a hypothetical accident was 590 mSv.The consequences of the mobile microreactor under the hypothetical accident far exceed the irradiation dose limits for workers in SSG-26 Advisory Material for the IAEA Regulations for the Safe Transport of Radioactive Material and the GB 18871-2002"Safety Standard for Protection against Ionizing Radiation and Radiation Sources".Moreover,the probability of hypothetical accidents does not meet China's nuclear safety guidelines screening requirement of 10-7/year for beyond design basis accidents.Therefore,it is necessary to take management measures,including armed escort and route planning,during the transportation of mobile microreactors,to reduce the probability of hypothetical accidents,and to take corresponding emergency measures to mitigate the accident consequences of hypothetical accidents to meet the regulatory requirements of the nuclear safety authorities.
To accelerate fitness product development and innovation, we propose a patent knowledge graph. Using a patent database and TF-IDF, we identify key areas and terms. This forms a keyword graph with inflation word analysis, guiding innovation direction. Applying this to fitness rowing machine innovation identifies needs. Empowering R&D for swift decisions enhances competitiveness.
The current stereo warehouse in the cold chain logistics industry faces problems such as high product loss rate, severe temperature deviations, and low level of informatization. To ensure the food quality and safety of cold chain logistics warehouses, and achieve cost reduction and efficiency improvement, this study focuses on the operational scenarios of stereo warehouses in cold chain logistics, and designs a five-dimensional digital twin model with full mapping and multidimensional simulation. By integrating heterogeneous data from multiple sources, it achieves real-time visualization and monitoring of all elements in warehouses, and proposes a model optimization strategy that supports system-linked decision-making. This strategy intelligently adjusts the load and thermal distribution in the temperature-controlled zones of warehouses to maximize operational efficiency and reduce operating costs. Using this approach, a digital twin system for cold chain logistics warehouses was constructed. By comparing the warehouse operation data before and after optimization, the loss rate of fresh vegetables under the same storage conditions was reduced by 25-30%. This system achieves precise mapping and coordinated operation of real-time data from cold chain logistics warehouses and dynamic virtual models. The practical application of this solution is demonstrated in a cold-chain warehouse of a supply chain company in Guangdong, forming an integrated control model for cold chain logistics warehouses. This model provides a reference for the application of digital twin technology in the operation, scheduling, decision-making, and collaborative operations of cold chain logistics warehouses and offers new possibilities for establishing improved packaging for perishable products and ensuring cold chain food quality and safety.
The work aims to mine consumer preference information from online review data in order to explore the improvement strategy of Bluetooth headset design.The Python crawler was used to capture target consumer reviews,and the demand topic and keywords were located through data mining and text analysis.Based on the theory of consumer preference,sentiment analysis and demand description of product functional attributes were conducted to control vari-ables,and the Mixed-logit model was used to extract consumer preference characteristics,so as to seek the optimal design strategy.Through quantitative empirical research,the significant expression of preference characteristic parameters was analyzed by regression,and an example of Bluetooth headset improvement strategy was generated,and its feasibility was verified by a satisfaction test.The combination of review mining and Mixed-logit model can not only design the product design scheme with consumer preference as the core,but also provide guidance and suggestions for the improvement of related product design strategies,which has a certain degree of innovation and practicality.
Taking the machete arm and the paper as flexible bodies, a rigid-flexible coupling dynamic model of the web paper knife-type folding mechanism was established. The relationship between the deformation of the machete arm and the lateral displacement of the machete head was analyzed to determine the maximum rotation speed of the folding mechanism to ensure the folding accuracy. Then, the dynamic contact excitation between the machete and the paper was analyzed, and the working loads of the machete were determined. Finally, the dynamic analytical model of the rigid folding mechanism was established to compare with the analytical values of the rigid-flexible coupling model, it was found that when the rotation speed of the folding mechanism was greater than 25,000 rph, the deviation of the two support reaction forces was significant, and the influence of the machete arm deformation cannot be ignored. The study has certain reference value for the simulation and experimental research of web folding mechanism.
