A new type of impedance-balanced ship equipment foundation structure based on the principle of impedance balancing using a“discontinuous panel-vibration isolation liquid layer-foundation structure”is proposed to sol...A new type of impedance-balanced ship equipment foundation structure based on the principle of impedance balancing using a“discontinuous panel-vibration isolation liquid layer-foundation structure”is proposed to solve the problem of poor low-frequency vibration isolation of the foundation under unbalanced excitation of shipboard equipment.Based on the finite element method,the influence of characteristic parameters of the foundation panel structure on its vibration reduction characteristics under unbalanced excitation is explored.The results show that the vibration isolation level of the impedance-balanced foundation is 10 dB higher than the traditional foundation in the low-frequency band of 10-500 Hz when subjected to combined excitation of concentrated force and moment.Increasing the thickness of the impedance-balanced foundation panel can enhance the isolation effect.Increasing the number of sub-panels can effectively reduce the vibration response of the foundation panel and enhance the isolation performance of the foundation.The connection stiffness between sub-panels has a small effect on the isolation performance of the foundation.展开更多
Aiming at defects such as low contrast in infrared ship images,uneven distribution of ship size,and lack of texture details,which will lead to unmanned ship leakage misdetection and slow detection,this paper proposes ...Aiming at defects such as low contrast in infrared ship images,uneven distribution of ship size,and lack of texture details,which will lead to unmanned ship leakage misdetection and slow detection,this paper proposes an infrared ship detection model based on the improved YOLOv8 algorithm(R_YOLO).The algorithm incorporates the Efficient Multi-Scale Attention mechanism(EMA),the efficient Reparameterized Generalized-feature extraction module(CSPStage),the small target detection header,the Repulsion Loss function,and the context aggregation block(CABlock),which are designed to improve the model’s ability to detect targets at multiple scales and the speed of model inference.The algorithm is validated in detail on two vessel datasets.The comprehensive experimental results demonstrate that,in the infrared dataset,the YOLOv8s algorithm exhibits improvements in various performance metrics.Specifically,compared to the baseline algorithm,there is a 3.1%increase in mean average precision at a threshold of 0.5(mAP(0.5)),a 5.4%increase in recall rate,and a 2.2%increase in mAP(0.5:0.95).Simultaneously,while less than 5 times parameters,the mAP(0.5)and frames per second(FPS)exhibit an increase of 1.7%and more than 3 times,respectively,compared to the CAA_YOLO algorithm.Finally,the evaluation indexes on the visible light data set have shown an average improvement of 4.5%.展开更多
ZTE Corporation announced on November 6, 2009 that the company has received the prestigious "World’s Best CDMA Equipment Manufacturer 2009" award from research and consulting firm Frost & Sullivan.
ZTE Corporation, a leading global provider of telecommunications equipment and network solutions, launched a prototype of the world’s first symmetrical 10G EPON equipment at the China FTTH Summit 2009, as well as
Great changes have taken place in China’s medical equipment and instruments industry since the launch of the reform. The industry has evolved a new structure consisting of various economic sectors.
ZTE Corporation announced on February 9 that it had received the Best Practice Award for being Frost ＆ Sullivan＇s ＂2010 SDR Equipment Vendor of the Year.＂ This award recognizes ZTE＇s outstanding contribution to t...ZTE Corporation announced on February 9 that it had received the Best Practice Award for being Frost ＆ Sullivan＇s ＂2010 SDR Equipment Vendor of the Year.＂ This award recognizes ZTE＇s outstanding contribution to the development of Software Defined Radio （SDR） technology and the wireless communications industry.展开更多
1. The present manufacturing situation of China’s thermal power generation equipment By the year 1995. development of China’s electric power industry has experienced a course of a hundred years. Over a period of the...1. The present manufacturing situation of China’s thermal power generation equipment By the year 1995. development of China’s electric power industry has experienced a course of a hundred years. Over a period of the initial 50 years. China’s development of electric power was slow. At the time of 1949, the total installed capacity in China was 1,850 MW and the electricity generated was only 4.3 billion kWh. During the past 46 years after 1949, her展开更多
基金funded by the National Natural Science Foundation of China(Grant Numbers.U2006229 and 52101351)。
文摘A new type of impedance-balanced ship equipment foundation structure based on the principle of impedance balancing using a“discontinuous panel-vibration isolation liquid layer-foundation structure”is proposed to solve the problem of poor low-frequency vibration isolation of the foundation under unbalanced excitation of shipboard equipment.Based on the finite element method,the influence of characteristic parameters of the foundation panel structure on its vibration reduction characteristics under unbalanced excitation is explored.The results show that the vibration isolation level of the impedance-balanced foundation is 10 dB higher than the traditional foundation in the low-frequency band of 10-500 Hz when subjected to combined excitation of concentrated force and moment.Increasing the thickness of the impedance-balanced foundation panel can enhance the isolation effect.Increasing the number of sub-panels can effectively reduce the vibration response of the foundation panel and enhance the isolation performance of the foundation.The connection stiffness between sub-panels has a small effect on the isolation performance of the foundation.
文摘Aiming at defects such as low contrast in infrared ship images,uneven distribution of ship size,and lack of texture details,which will lead to unmanned ship leakage misdetection and slow detection,this paper proposes an infrared ship detection model based on the improved YOLOv8 algorithm(R_YOLO).The algorithm incorporates the Efficient Multi-Scale Attention mechanism(EMA),the efficient Reparameterized Generalized-feature extraction module(CSPStage),the small target detection header,the Repulsion Loss function,and the context aggregation block(CABlock),which are designed to improve the model’s ability to detect targets at multiple scales and the speed of model inference.The algorithm is validated in detail on two vessel datasets.The comprehensive experimental results demonstrate that,in the infrared dataset,the YOLOv8s algorithm exhibits improvements in various performance metrics.Specifically,compared to the baseline algorithm,there is a 3.1%increase in mean average precision at a threshold of 0.5(mAP(0.5)),a 5.4%increase in recall rate,and a 2.2%increase in mAP(0.5:0.95).Simultaneously,while less than 5 times parameters,the mAP(0.5)and frames per second(FPS)exhibit an increase of 1.7%and more than 3 times,respectively,compared to the CAA_YOLO algorithm.Finally,the evaluation indexes on the visible light data set have shown an average improvement of 4.5%.
文摘ZTE Corporation announced on November 6, 2009 that the company has received the prestigious "World’s Best CDMA Equipment Manufacturer 2009" award from research and consulting firm Frost & Sullivan.
文摘ZTE Corporation, a leading global provider of telecommunications equipment and network solutions, launched a prototype of the world’s first symmetrical 10G EPON equipment at the China FTTH Summit 2009, as well as
文摘Great changes have taken place in China’s medical equipment and instruments industry since the launch of the reform. The industry has evolved a new structure consisting of various economic sectors.
文摘ZTE Corporation announced on February 9 that it had received the Best Practice Award for being Frost ＆ Sullivan＇s ＂2010 SDR Equipment Vendor of the Year.＂ This award recognizes ZTE＇s outstanding contribution to the development of Software Defined Radio （SDR） technology and the wireless communications industry.
文摘1. The present manufacturing situation of China’s thermal power generation equipment By the year 1995. development of China’s electric power industry has experienced a course of a hundred years. Over a period of the initial 50 years. China’s development of electric power was slow. At the time of 1949, the total installed capacity in China was 1,850 MW and the electricity generated was only 4.3 billion kWh. During the past 46 years after 1949, her
