For the solution of peridynamic equations of motion,a meshless approach is typically used instead of utilizing semi-analytical or mesh-based approaches.In contrast,the literature has limited analytical solutions.This ...For the solution of peridynamic equations of motion,a meshless approach is typically used instead of utilizing semi-analytical or mesh-based approaches.In contrast,the literature has limited analytical solutions.This study develops a novel analytical solution for one-dimensional peridynamic models,considering the effect of damping.After demonstrating the details of the analytical solution,various demonstration problems are presented.First,the free vibration of a damped system is considered for under-damped and critically damped conditions.Peridynamic solutions and results from the classical theory are compared against each other,and excellent agreement is observed between the two approaches.Next,forced vibration analyses of undamped and damped conditions are performed.In addition,the effect of horizon size is investigated.It is shown that for smaller horizon sizes,peridynamic results agree well with classical results,whereas results from these two approaches deviate from each other as the horizon size increases.展开更多
Installing annular wave-energy converters(WECs)on the columns of floating wind platforms in the form of a coaxial-cylinder provides a convenient means of integration.Extant coaxial-cylinder-type wind-wave hybrid syste...Installing annular wave-energy converters(WECs)on the columns of floating wind platforms in the form of a coaxial-cylinder provides a convenient means of integration.Extant coaxial-cylinder-type wind-wave hybrid systems are mostly based on single-column platforms such as spars(single coaxial-cylinder hybrid system'hereafter).Systems based on multiple-column platforms such as semi-submersible platforms('multiple coaxial-cylinder hybrid systems'hereafter)are rarely seen or studied,despite their superiority in wave-power absorption due to the use of multiple WECs as well as in dynamic stability.This paper proposes a novel WindFloat-annular-WEC hybrid system,based on our study investigating its dynamic and power features,and optimizing the geometry and power take-off of the WECs.Our results show that the dynamic and power features of a multiple coaxial-cylinder hybrid system are different from those of a single coaxial-cylinder hybrid system,so the same optimization parameters cannot be directly applied.Flatter annular WECs absorb slightly more power in a wider wave-period range,but their geometry is confined by limitations in installation and structural strength.The overall effect of an oblique incident wave is greater intensity in the motions of the hybrid system in yaw and the direction perpendicular to propagation,although the difference is small and maybe negligible.展开更多
As a new kind of autonomous underwater vehicle,bionic submersible has many merits such as high efficiency and low costs.In order to obtain such advantages,it is a good way to simulate the shapes of marine animals and ...As a new kind of autonomous underwater vehicle,bionic submersible has many merits such as high efficiency and low costs.In order to obtain such advantages,it is a good way to simulate the shapes of marine animals and apply them to the design of artificial underwater vehicle.In this paper,an optimization system of airfoils is proposed by the improved class-shape-transformation(CST)parameterization method and genetic algorithm(GA).The appearance of a manta-ray-inspired underwater vehicle is rebuilt using the optimal sectional airfoils obtained by the proposed optimization system.Computational simulations are carried out to investigate the hydrodynamic performance of the submersible using the commercial computational fluid dynamics(CFD)code Fluent.The results demonstrate that the maximum thickness of the vehicle increases by 9%,which means the loading capacity is increased.Moreover,the underwater vehicle shows better hydrodynamic performance,and the lift-drag ratio of initial design is increased by more than 10%using the presented optimization system of airfoils.展开更多
In this paper,we focus on the two-dimensional pulsating nanofluid flow through a parallel-plate channel in the presence of a magnetic field.The pulsating flow is produced by an applied pressure gradient that fluctuate...In this paper,we focus on the two-dimensional pulsating nanofluid flow through a parallel-plate channel in the presence of a magnetic field.The pulsating flow is produced by an applied pressure gradient that fluctuates with a small amplitude.A kind of proper transformation is used so that the governing equations describing the momentum and thermal energy are reduced to a set of non-dimensional equations.The analytical expressions of the pulsating velocity,temperature,and Nusselt number of nanofluids are obtained by the perturbation technique.In the present study,the effects of the Cu-H2O and Al_(2)O_(3)-H2O nanofluids on the flow and heat transfer in pulsating flow are compared and analyzed.The results show that the convective heat transfer effect of Cu-H2O nanofluids is better than that of Al_(2)O_(3)-H2O nanofluids.Also,the effects of the Hartmann number and pulsation amplitude on the velocity,temperature,and Nusselt number are examined and discussed in detail.The present work indicates that increasing the Hartmann number and pulsation amplitude can enhance the heat transfer of the pulsating flow.In addition,selecting an optimal pulsation frequency can maximize the convective heat transfer of the pulsating flow.Therefore,improved understanding of these fundamental mechanisms is conducive to the optimal design of thermal systems.展开更多
Under the as-welded condition the fatigue crack initiation period was considered nonexistent and Linear Elastic Fracture Mechanics（LEFM） was used to calculate fatigue strength for a range of weld geometries. Fractur...Under the as-welded condition the fatigue crack initiation period was considered nonexistent and Linear Elastic Fracture Mechanics（LEFM） was used to calculate fatigue strength for a range of weld geometries. Fracture mechanics assessment of welded joints requires accurate solutions for stress intensity factor（SIF）. However, the solutions for the SIF of complex welded joints are dificult to determine due to the complicated correction factors. Three methods for SIF prediction are discussed on illet welded specimens containing continuous or semi-elliptical surface cracks, including the traditional correction method Mk, the approximate correction method Kt, and the suggested additional crack size method（ac＋ae）.The new additional crack parameter ae is used to replace the stress concentration effect of weld proile Mk, which simpliies the calculation process. Experimental results are collected to support fatigue strength assessment of the additional crack size method.展开更多
Prostate and bladder cancers are one of the cancers occurring worldwide.In addition to radical surgery,the past decade has also focused on targeted therapy of overexpressed cancer proteins that are lethal and critical...Prostate and bladder cancers are one of the cancers occurring worldwide.In addition to radical surgery,the past decade has also focused on targeted therapy of overexpressed cancer proteins that are lethal and critical for cancer cell survival.However,targeted therapy cannot adapt for changing of cancer molecular characteristics and,ultimately,a clone that bypasses the targeted therapy emerges.This can be overcome by immunotherapy.New studies on ablative therapy of cancers show presence of immunomodulatory effect in these modalities.Tumor ablation prime the immune system for further destruction of persistent primary tumor in addition to destruction of concurrent metastatic disease and also reduce recurrence.Ablative therapies can achieve a state of increased antigenicity.Its combination with a novel macrophage targeted therapy may enhance immune priming,trafficking,and/or effector phases;thereby improving clinical outcomes.Tumor associated macrophages or M2 phenotype are now known to mediate this immunosuppressive pro-tumorigenic effect.Alteration of macrophage differentiation may enhance tumor destruction of ablative therapy.This breakthrough in immunotherapy opens up arenas for further robust clinical trials on combinatorial therapies.In the present review,we aim to elucidate the major aspects of immune stimulatory minimal invasive approaches by combining with macrophage directed pathways.展开更多
文摘For the solution of peridynamic equations of motion,a meshless approach is typically used instead of utilizing semi-analytical or mesh-based approaches.In contrast,the literature has limited analytical solutions.This study develops a novel analytical solution for one-dimensional peridynamic models,considering the effect of damping.After demonstrating the details of the analytical solution,various demonstration problems are presented.First,the free vibration of a damped system is considered for under-damped and critically damped conditions.Peridynamic solutions and results from the classical theory are compared against each other,and excellent agreement is observed between the two approaches.Next,forced vibration analyses of undamped and damped conditions are performed.In addition,the effect of horizon size is investigated.It is shown that for smaller horizon sizes,peridynamic results agree well with classical results,whereas results from these two approaches deviate from each other as the horizon size increases.
基金supported by the National Natural Science Foundation of China(Nos.52201322,52222109,and 52071096)the Guangdong Basic and Applied Basic Research Foundation(Nos.2022B1515020036 and 2023A1515012144)the Natural Science Foundation of Guangzhou City(No.202201010055),China.
文摘Installing annular wave-energy converters(WECs)on the columns of floating wind platforms in the form of a coaxial-cylinder provides a convenient means of integration.Extant coaxial-cylinder-type wind-wave hybrid systems are mostly based on single-column platforms such as spars(single coaxial-cylinder hybrid system'hereafter).Systems based on multiple-column platforms such as semi-submersible platforms('multiple coaxial-cylinder hybrid systems'hereafter)are rarely seen or studied,despite their superiority in wave-power absorption due to the use of multiple WECs as well as in dynamic stability.This paper proposes a novel WindFloat-annular-WEC hybrid system,based on our study investigating its dynamic and power features,and optimizing the geometry and power take-off of the WECs.Our results show that the dynamic and power features of a multiple coaxial-cylinder hybrid system are different from those of a single coaxial-cylinder hybrid system,so the same optimization parameters cannot be directly applied.Flatter annular WECs absorb slightly more power in a wider wave-period range,but their geometry is confined by limitations in installation and structural strength.The overall effect of an oblique incident wave is greater intensity in the motions of the hybrid system in yaw and the direction perpendicular to propagation,although the difference is small and maybe negligible.
基金the National Key Research and Development Plan of China(No.2016YFC0301300)
文摘As a new kind of autonomous underwater vehicle,bionic submersible has many merits such as high efficiency and low costs.In order to obtain such advantages,it is a good way to simulate the shapes of marine animals and apply them to the design of artificial underwater vehicle.In this paper,an optimization system of airfoils is proposed by the improved class-shape-transformation(CST)parameterization method and genetic algorithm(GA).The appearance of a manta-ray-inspired underwater vehicle is rebuilt using the optimal sectional airfoils obtained by the proposed optimization system.Computational simulations are carried out to investigate the hydrodynamic performance of the submersible using the commercial computational fluid dynamics(CFD)code Fluent.The results demonstrate that the maximum thickness of the vehicle increases by 9%,which means the loading capacity is increased.Moreover,the underwater vehicle shows better hydrodynamic performance,and the lift-drag ratio of initial design is increased by more than 10%using the presented optimization system of airfoils.
基金Project supported by the China Postdoctoral Science Foundation(No.2018M631909)the Doctor of Entrepreneurship and Innovation Project of Jiangsu Province(No.JSSCBS20221300)。
文摘In this paper,we focus on the two-dimensional pulsating nanofluid flow through a parallel-plate channel in the presence of a magnetic field.The pulsating flow is produced by an applied pressure gradient that fluctuates with a small amplitude.A kind of proper transformation is used so that the governing equations describing the momentum and thermal energy are reduced to a set of non-dimensional equations.The analytical expressions of the pulsating velocity,temperature,and Nusselt number of nanofluids are obtained by the perturbation technique.In the present study,the effects of the Cu-H2O and Al_(2)O_(3)-H2O nanofluids on the flow and heat transfer in pulsating flow are compared and analyzed.The results show that the convective heat transfer effect of Cu-H2O nanofluids is better than that of Al_(2)O_(3)-H2O nanofluids.Also,the effects of the Hartmann number and pulsation amplitude on the velocity,temperature,and Nusselt number are examined and discussed in detail.The present work indicates that increasing the Hartmann number and pulsation amplitude can enhance the heat transfer of the pulsating flow.In addition,selecting an optimal pulsation frequency can maximize the convective heat transfer of the pulsating flow.Therefore,improved understanding of these fundamental mechanisms is conducive to the optimal design of thermal systems.
基金Project supported by the National Natural Science Foundation of China(No.51609185)the State Key Laboratory of Ocean Engineering in Shanghai Jiao Tong University(No.1613)
文摘Under the as-welded condition the fatigue crack initiation period was considered nonexistent and Linear Elastic Fracture Mechanics（LEFM） was used to calculate fatigue strength for a range of weld geometries. Fracture mechanics assessment of welded joints requires accurate solutions for stress intensity factor（SIF）. However, the solutions for the SIF of complex welded joints are dificult to determine due to the complicated correction factors. Three methods for SIF prediction are discussed on illet welded specimens containing continuous or semi-elliptical surface cracks, including the traditional correction method Mk, the approximate correction method Kt, and the suggested additional crack size method（ac＋ae）.The new additional crack parameter ae is used to replace the stress concentration effect of weld proile Mk, which simpliies the calculation process. Experimental results are collected to support fatigue strength assessment of the additional crack size method.
文摘Prostate and bladder cancers are one of the cancers occurring worldwide.In addition to radical surgery,the past decade has also focused on targeted therapy of overexpressed cancer proteins that are lethal and critical for cancer cell survival.However,targeted therapy cannot adapt for changing of cancer molecular characteristics and,ultimately,a clone that bypasses the targeted therapy emerges.This can be overcome by immunotherapy.New studies on ablative therapy of cancers show presence of immunomodulatory effect in these modalities.Tumor ablation prime the immune system for further destruction of persistent primary tumor in addition to destruction of concurrent metastatic disease and also reduce recurrence.Ablative therapies can achieve a state of increased antigenicity.Its combination with a novel macrophage targeted therapy may enhance immune priming,trafficking,and/or effector phases;thereby improving clinical outcomes.Tumor associated macrophages or M2 phenotype are now known to mediate this immunosuppressive pro-tumorigenic effect.Alteration of macrophage differentiation may enhance tumor destruction of ablative therapy.This breakthrough in immunotherapy opens up arenas for further robust clinical trials on combinatorial therapies.In the present review,we aim to elucidate the major aspects of immune stimulatory minimal invasive approaches by combining with macrophage directed pathways.
