Degenerative diseases significantly reduce the quality of human life.Non-invasive treatments are used in the initial stages of osteoarthritis(OA).Total knee arthroplasty is used in the late stages of osteoarthritis of...Degenerative diseases significantly reduce the quality of human life.Non-invasive treatments are used in the initial stages of osteoarthritis(OA).Total knee arthroplasty is used in the late stages of osteoarthritis of the knee joint.Non-invasive methods based on mechanical action are also used for the rehabilitation of a patient after arthroplasty.This paper presents numerical models of the knee joint with degenerative OA changes and arthroplasty.Using these models,a computational study was made of the influence of the intensity of shock-wave exposure on the conditioning for the regeneration of bone and cartilage tissues.Based on the modeling results,it was found that in the knee joint with degenerative OA changes,conditions for the regeneration of cartilage and meniscus tissues were fulfilled under medium and highintensity loading.Under high-intensity loading(up to 0.9 m J/mm^(2)),the stress level was significantly below the ultimate value required for fracture.At knee arthroplasty,the conditions for bone tissue regeneration around the tibia component are fulfilled only under high-intensity loading.展开更多
The injury of gunners caused by muzzle shock-wave has always been a great problem when firing inside the protective cover. The distribution regularity and personnel injury from the muzzle blast-wave were investigated ...The injury of gunners caused by muzzle shock-wave has always been a great problem when firing inside the protective cover. The distribution regularity and personnel injury from the muzzle blast-wave were investigated by both test and numerical simulation. Through the inside firing test, the changes of overpressure and noise have been measured at different measuring points in the thin-wall cover structure with different open widths and shallow covering thickness. The distribution regularity of muzzle shock-wave with different firing port widths is calculated by ANSYS/LSDYNA software. The overpressure distribution curves of muzzle shock-wave inside the structure can be obtained by comparing the test results with the numerical results. Then, the influence of open width and shallow covering thickness is proposed to give a reference to the protective design under the condition of the inside firing with the same cannon caliber.展开更多
In this paper, the quantum hydrodynamics (QHD) model is used to study the propagation of small- but finite-amplitude quantum electrostatic shock-wave in an inertial-less symmetric pair (ion) plasma with immobile backg...In this paper, the quantum hydrodynamics (QHD) model is used to study the propagation of small- but finite-amplitude quantum electrostatic shock-wave in an inertial-less symmetric pair (ion) plasma with immobile background positive constituents. The dispersion due to the quantum tunneling and inertial effects as well as dissipation caused by particle collisions leading to the shock-like or double-layer structures are considered. Investigation of both the stationary and traveling-wave solutions to Kortewege-de Veries-Burgers evolution equation show that critical values exist which govern the type of collective plasma structures. Current analysis apply to diverse kind of symmetric plasmas such as laboratory inertially confined or astrophysical pair-ion or electron-positron degenerate plasmas.展开更多
基金financial support of the Russian Foundation for Basic Research,grant No.20-08-00818(simulation results)the Government research assignment for ISPMS SB RAS,project FWRW-2021-009(in-house software development)。
文摘Degenerative diseases significantly reduce the quality of human life.Non-invasive treatments are used in the initial stages of osteoarthritis(OA).Total knee arthroplasty is used in the late stages of osteoarthritis of the knee joint.Non-invasive methods based on mechanical action are also used for the rehabilitation of a patient after arthroplasty.This paper presents numerical models of the knee joint with degenerative OA changes and arthroplasty.Using these models,a computational study was made of the influence of the intensity of shock-wave exposure on the conditioning for the regeneration of bone and cartilage tissues.Based on the modeling results,it was found that in the knee joint with degenerative OA changes,conditions for the regeneration of cartilage and meniscus tissues were fulfilled under medium and highintensity loading.Under high-intensity loading(up to 0.9 m J/mm^(2)),the stress level was significantly below the ultimate value required for fracture.At knee arthroplasty,the conditions for bone tissue regeneration around the tibia component are fulfilled only under high-intensity loading.
基金Supported by National Natural Science Foundation of China (No. 50578082)
文摘The injury of gunners caused by muzzle shock-wave has always been a great problem when firing inside the protective cover. The distribution regularity and personnel injury from the muzzle blast-wave were investigated by both test and numerical simulation. Through the inside firing test, the changes of overpressure and noise have been measured at different measuring points in the thin-wall cover structure with different open widths and shallow covering thickness. The distribution regularity of muzzle shock-wave with different firing port widths is calculated by ANSYS/LSDYNA software. The overpressure distribution curves of muzzle shock-wave inside the structure can be obtained by comparing the test results with the numerical results. Then, the influence of open width and shallow covering thickness is proposed to give a reference to the protective design under the condition of the inside firing with the same cannon caliber.
文摘In this paper, the quantum hydrodynamics (QHD) model is used to study the propagation of small- but finite-amplitude quantum electrostatic shock-wave in an inertial-less symmetric pair (ion) plasma with immobile background positive constituents. The dispersion due to the quantum tunneling and inertial effects as well as dissipation caused by particle collisions leading to the shock-like or double-layer structures are considered. Investigation of both the stationary and traveling-wave solutions to Kortewege-de Veries-Burgers evolution equation show that critical values exist which govern the type of collective plasma structures. Current analysis apply to diverse kind of symmetric plasmas such as laboratory inertially confined or astrophysical pair-ion or electron-positron degenerate plasmas.
