It is difficult to compute far-field waves in a relative large area by using one wave generation model when a large calculation domain is needed because of large dimensions of the waterway and long distance of the req...It is difficult to compute far-field waves in a relative large area by using one wave generation model when a large calculation domain is needed because of large dimensions of the waterway and long distance of the required computing points. Variation of waterway bathymetry and nonlinearity in the far field cannot be included in a ship fixed process either. A coupled method combining a wave generation model and wave propagation model is then used in this paper to simulate the wash waves generated by the passing ship. A NURBS-based higher order panel method is adopted as the stationary wave generation model; a wave spectrum method and Boussinesq-type equation wave model are used as the wave propagation model for the constant water depth condition and variable water depth condition, respectively. The waves calculated by the NURBS-based higher order panel method in the near field are used as the input for the wave spectrum method and the Boussinesq-type equation wave model to obtain the far-field waves. With this approach it is possible to simulate the ship wash waves including the effects of water depth and waterway bathymetry. Parts of the calculated results are validated experimentally, and the agreement is demonstrated. The effects of ship wash waves on the moored ship are discussed by using a diffraction theory method. The results indicate that the prediction of the ship induced waves by coupling models is feasible.展开更多
目的探讨活血通络汤外洗联合冲击波治疗跟痛症的临床效果。方法选取2020年1月—2022年12月武警第一机动总队医院收治的80例跟痛症患者为研究对象。按照治疗方法不同分为两组,各40例。对照组采用局部冲击波治疗,观察组在对照组治疗的基...目的探讨活血通络汤外洗联合冲击波治疗跟痛症的临床效果。方法选取2020年1月—2022年12月武警第一机动总队医院收治的80例跟痛症患者为研究对象。按照治疗方法不同分为两组,各40例。对照组采用局部冲击波治疗,观察组在对照组治疗的基础上结合活血通络汤外洗治疗。比较两组治疗后每日跟痛持续时间、视觉模拟评分法(Visual Analog Scale,VAS)评分、Maryland足跟功能评分,统计两组治疗效果、并发症发生率,并随访1年,比较复发率。结果治疗后,观察组每日跟痛持续时间为(0.6±0.2)h,短于对照组的(5.6±1.8)h,差异有统计学意义(t=17.329,P<0.05)。治疗后,观察组VAS评分低于对照组,差异有统计学意义(P<0.05)。治疗后,两组Maryland足跟功能评分均高于治疗前,且观察组高于对照组,差异有统计学意义(P均<0.05)。观察组治疗总有效率高于对照组,1年复发率低于对照组,差异有统计学意义(P均<0.05)。两组并发症发生率比较,差异无统计学意义(P>0.05)。结论跟痛症患者在使用冲击波治疗基础上联合应用活血通络汤外洗,可快速缓解患者足跟部疼痛,改善足部功能,提高治疗有效率,降低复发率,且不良反应少,安全性高。展开更多
Linear and nonlinear analyses of water waves in an elastic vessel are carried out to study the dramatic phenomena of Dragon Wash as well as related controllable experiments. It is proposed that the capillary edge wave...Linear and nonlinear analyses of water waves in an elastic vessel are carried out to study the dramatic phenomena of Dragon Wash as well as related controllable experiments. It is proposed that the capillary edge waves are generated by parametric resonance, which is shown to be a possible mechanism for both rectangular an circular vessels. For circular vessel, the normal geometric resonance is also operating, thus greatly. enhance the dramatic effect. The mechanism of nonlinear mode-mode interaction is proposed far the generation of axisymmetric low-frequency gravity waves by the high-frequency external excitation. A simple model system is studied numerically to demonstrate explicitly this interaction mechanism.展开更多
Recent experiments related to the Dragon Wash phenomena showed that axisymmetric capillary waves appear first from excitation, and circumferential capillary waves appear after increase of the excitation strength. Base...Recent experiments related to the Dragon Wash phenomena showed that axisymmetric capillary waves appear first from excitation, and circumferential capillary waves appear after increase of the excitation strength. Based on this new finding, a theory of parametric resonance is developed in detail to explain the on- set of the prominent circumferential capillary waves. Numerical computation is also carried out and the results agree generally with the experiments. Analysis and nu- merical computation are also presented to explain the generation of axisymmetric low-frequency gravity waves by tile high-frequency external excitation.展开更多
基金financially supported by the National Natural Science Foundation of China(Grant Nos.50879066 and 51409201)the Research Fund for the Doctoral Program of Higher Education of China(Grant No.200804970009)
文摘It is difficult to compute far-field waves in a relative large area by using one wave generation model when a large calculation domain is needed because of large dimensions of the waterway and long distance of the required computing points. Variation of waterway bathymetry and nonlinearity in the far field cannot be included in a ship fixed process either. A coupled method combining a wave generation model and wave propagation model is then used in this paper to simulate the wash waves generated by the passing ship. A NURBS-based higher order panel method is adopted as the stationary wave generation model; a wave spectrum method and Boussinesq-type equation wave model are used as the wave propagation model for the constant water depth condition and variable water depth condition, respectively. The waves calculated by the NURBS-based higher order panel method in the near field are used as the input for the wave spectrum method and the Boussinesq-type equation wave model to obtain the far-field waves. With this approach it is possible to simulate the ship wash waves including the effects of water depth and waterway bathymetry. Parts of the calculated results are validated experimentally, and the agreement is demonstrated. The effects of ship wash waves on the moored ship are discussed by using a diffraction theory method. The results indicate that the prediction of the ship induced waves by coupling models is feasible.
文摘目的探讨活血通络汤外洗联合冲击波治疗跟痛症的临床效果。方法选取2020年1月—2022年12月武警第一机动总队医院收治的80例跟痛症患者为研究对象。按照治疗方法不同分为两组,各40例。对照组采用局部冲击波治疗,观察组在对照组治疗的基础上结合活血通络汤外洗治疗。比较两组治疗后每日跟痛持续时间、视觉模拟评分法(Visual Analog Scale,VAS)评分、Maryland足跟功能评分,统计两组治疗效果、并发症发生率,并随访1年,比较复发率。结果治疗后,观察组每日跟痛持续时间为(0.6±0.2)h,短于对照组的(5.6±1.8)h,差异有统计学意义(t=17.329,P<0.05)。治疗后,观察组VAS评分低于对照组,差异有统计学意义(P<0.05)。治疗后,两组Maryland足跟功能评分均高于治疗前,且观察组高于对照组,差异有统计学意义(P均<0.05)。观察组治疗总有效率高于对照组,1年复发率低于对照组,差异有统计学意义(P均<0.05)。两组并发症发生率比较,差异无统计学意义(P>0.05)。结论跟痛症患者在使用冲击波治疗基础上联合应用活血通络汤外洗,可快速缓解患者足跟部疼痛,改善足部功能,提高治疗有效率,降低复发率,且不良反应少,安全性高。
文摘Linear and nonlinear analyses of water waves in an elastic vessel are carried out to study the dramatic phenomena of Dragon Wash as well as related controllable experiments. It is proposed that the capillary edge waves are generated by parametric resonance, which is shown to be a possible mechanism for both rectangular an circular vessels. For circular vessel, the normal geometric resonance is also operating, thus greatly. enhance the dramatic effect. The mechanism of nonlinear mode-mode interaction is proposed far the generation of axisymmetric low-frequency gravity waves by the high-frequency external excitation. A simple model system is studied numerically to demonstrate explicitly this interaction mechanism.
文摘Recent experiments related to the Dragon Wash phenomena showed that axisymmetric capillary waves appear first from excitation, and circumferential capillary waves appear after increase of the excitation strength. Based on this new finding, a theory of parametric resonance is developed in detail to explain the on- set of the prominent circumferential capillary waves. Numerical computation is also carried out and the results agree generally with the experiments. Analysis and nu- merical computation are also presented to explain the generation of axisymmetric low-frequency gravity waves by tile high-frequency external excitation.
