This paper investigates the effects of charge parameters of the underwater contact explosion based on the axisymmetric smoothed particle hydrodynamics （SPH） method. The dynamic boundary particle is proposed to impro...This paper investigates the effects of charge parameters of the underwater contact explosion based on the axisymmetric smoothed particle hydrodynamics （SPH） method. The dynamic boundary particle is proposed to improve the pressure fluctuation and numerical accuracy near the symmetric axis. An in-depth study is carried out over the influence of charge shapes and detonation modes on the near-field loads in terms of the peak pressure and impulse of shock waves. For different charge shapes, the cylindrical charge with different length-diameter ratios may cause strong directivity of peak pressure and impulse in the near field. Compared with spherical charge, the peak pressure of cylindrical charge may be either weakened or enhanced in different directions. Within a certain range, the greater the length-diameter ratio is, the more obvious the effect will be. The weakened ratio near the detonation end may reach 25% approximately, while the enhanced ratio may reach around 20% in the opposite direction. However, the impulse in different directions seems to be uniform. For different detonation modes, compared with point-source explosion, the peak pressure of plane-source explosion is enhanced by about 5%. Besides, the impulse of plane-source explosion is enhanced by around 5% near the detonation end, but close to those of the point-source explosion in other directions. Based on the material constitutive relation in the axisymmetric coordinates, a simple case of underwater contact explosion is simulated to verify the above conclusions, showing that the charge parameters of underwater contact explosion should not be ignored.展开更多
Aimed at the abominable influences to blind equaliza-tion algorithms caused by complex time-space variability existing in underwater acoustic channels, a new self-adjusting decision feedback equalization （DFE） algor...Aimed at the abominable influences to blind equaliza-tion algorithms caused by complex time-space variability existing in underwater acoustic channels, a new self-adjusting decision feedback equalization （DFE） algorithm adapting to different under-water acoustic channel environments is proposed by changing its central tap position. Besides, this new algorithm behaves faster convergence speed based on the analysis of equalizers’ working rules, which is more suitable to implement communications in dif-ferent unknown channels. Corresponding results and conclusions are validated by simulations and spot experiments.展开更多
Gastroesophageal reflux disease(GERD)is a digestive system disease characterized by uncomfortable symptoms caused by reflux of gastric contents.It has increased sharply with the development of my country’s society an...Gastroesophageal reflux disease(GERD)is a digestive system disease characterized by uncomfortable symptoms caused by reflux of gastric contents.It has increased sharply with the development of my country’s society and economy.If there is no reasonable and effective Prevention and treatment measures will inevitably increase the financial burden of patients,and also pose a major threat to the quality of life and health of patients.Cell signal transduction mediated by various receptors participates in the regulation mechanism of the body's various levels of biological functions.By inhibiting or activating its functions,the purpose of curing diseases can be achieved,and cell signal transduction has been used in traditional Chinese medicine.Studying.The theory of"adjusting the central axis"was explored by Professor Xie Sheng through decades of clinical experience.It has been proven in practice to treat GERD.It starts from the model of TCM viscera and expounds that the pathogenesis of GERD involves multiple viscera.Multi-system and multi-factor,explain the correlation of the disease with a variety of zang-fu syndromes,and use this as a basis to guide the clinical use of hidden prescriptions.The back-shu pointer therapy can prevent GERD by correcting the unbalanced state of the viscera and qi machine,and promoting the junction of the two channels of Ren and Du.Based on the theory of"adjusting the hub by the pivot",this article expounds the pathogenesis of GERD from the perspective of traditional Chinese medicine.By consulting the literature and combining with the previous research,it proposes to analyze the methods and methods of Backshu pointer therapy to prevent and treat GERD from the AMPK/ULK1 mediated autophagy pathway.展开更多
基金supported by the National Natural Science Foundation of China(No.51379039)the Excellent Young Scientists Fund(No.51222904)
文摘This paper investigates the effects of charge parameters of the underwater contact explosion based on the axisymmetric smoothed particle hydrodynamics （SPH） method. The dynamic boundary particle is proposed to improve the pressure fluctuation and numerical accuracy near the symmetric axis. An in-depth study is carried out over the influence of charge shapes and detonation modes on the near-field loads in terms of the peak pressure and impulse of shock waves. For different charge shapes, the cylindrical charge with different length-diameter ratios may cause strong directivity of peak pressure and impulse in the near field. Compared with spherical charge, the peak pressure of cylindrical charge may be either weakened or enhanced in different directions. Within a certain range, the greater the length-diameter ratio is, the more obvious the effect will be. The weakened ratio near the detonation end may reach 25% approximately, while the enhanced ratio may reach around 20% in the opposite direction. However, the impulse in different directions seems to be uniform. For different detonation modes, compared with point-source explosion, the peak pressure of plane-source explosion is enhanced by about 5%. Besides, the impulse of plane-source explosion is enhanced by around 5% near the detonation end, but close to those of the point-source explosion in other directions. Based on the material constitutive relation in the axisymmetric coordinates, a simple case of underwater contact explosion is simulated to verify the above conclusions, showing that the charge parameters of underwater contact explosion should not be ignored.
基金supported by the National Natural Science Foundation of China(61101205)the Natural Science Foundation of Hubei Province of China(2009CDB337)the Natural Science Foundation of Naval University of Engineering(HGDQNJJ13019)
文摘Aimed at the abominable influences to blind equaliza-tion algorithms caused by complex time-space variability existing in underwater acoustic channels, a new self-adjusting decision feedback equalization （DFE） algorithm adapting to different under-water acoustic channel environments is proposed by changing its central tap position. Besides, this new algorithm behaves faster convergence speed based on the analysis of equalizers’ working rules, which is more suitable to implement communications in dif-ferent unknown channels. Corresponding results and conclusions are validated by simulations and spot experiments.
基金National Natural Science Foundation(No.82004299)Enhancement Program of Evidence-based Therapy of Digestive System Diseases(gastroesophageal reflux disease)with Traditional Chinese Medicine(No.2019XZZX-XH003)Innovation Planning Program of Postgraduate Students Education of Guangxi University of Traditional Chinese Medicine in 2020(No.YCSY2020030)。
文摘Gastroesophageal reflux disease(GERD)is a digestive system disease characterized by uncomfortable symptoms caused by reflux of gastric contents.It has increased sharply with the development of my country’s society and economy.If there is no reasonable and effective Prevention and treatment measures will inevitably increase the financial burden of patients,and also pose a major threat to the quality of life and health of patients.Cell signal transduction mediated by various receptors participates in the regulation mechanism of the body's various levels of biological functions.By inhibiting or activating its functions,the purpose of curing diseases can be achieved,and cell signal transduction has been used in traditional Chinese medicine.Studying.The theory of"adjusting the central axis"was explored by Professor Xie Sheng through decades of clinical experience.It has been proven in practice to treat GERD.It starts from the model of TCM viscera and expounds that the pathogenesis of GERD involves multiple viscera.Multi-system and multi-factor,explain the correlation of the disease with a variety of zang-fu syndromes,and use this as a basis to guide the clinical use of hidden prescriptions.The back-shu pointer therapy can prevent GERD by correcting the unbalanced state of the viscera and qi machine,and promoting the junction of the two channels of Ren and Du.Based on the theory of"adjusting the hub by the pivot",this article expounds the pathogenesis of GERD from the perspective of traditional Chinese medicine.By consulting the literature and combining with the previous research,it proposes to analyze the methods and methods of Backshu pointer therapy to prevent and treat GERD from the AMPK/ULK1 mediated autophagy pathway.
