A dynamic hierarchical description method for workflow is presented. The method provides a dynamic hierarchical way to define a workflow with non-determinate or dynamic factors. With this method, the main process defi...A dynamic hierarchical description method for workflow is presented. The method provides a dynamic hierarchical way to define a workflow with non-determinate or dynamic factors. With this method, the main process defined at build-time can be reified and extended by the principle of the sub-organizations at either the build-time or the run-time. To ensure the consistency and integrity of the description, a series of constraint rules are also discussed to realize seamless integration between a decomposed process and its original one. This approach supports the description of unpredictable uncertainties, the dynamic hierarchy of business process, and the dynamic modification of enterprise organizations, and all of these improve the flexibility and extendability of workflow management systems dramatically.展开更多
This paper presents a deep reflection on the advective wave equations for velocity vector and dilatation discovered in the past decade.We show that these equations can form the theoretical basis of modern gas dynamics...This paper presents a deep reflection on the advective wave equations for velocity vector and dilatation discovered in the past decade.We show that these equations can form the theoretical basis of modern gas dynamics,because they dominate not only various complex viscous and heat-conducting gas flows but also their associated longitudinal waves,including aero-generated sound.Current aeroacoustics theory has been developing in a manner quite independently of gas dynamics;it is based on the advective wave equations for thermodynamic variables,say the exact Phillips equation of relative disturbance pressure as a representative one.However,these equations do not cover the fluid flow that generates and propagates sound waves.In using them,one has to assume simplified base-flow models,which we argue is the main theoretical obstacle to identifying sound source and achieving effective noise control.Instead,we show that the Phillips equation and alike is nothing but the first integral of the dilatation equation that also governs the longitudinal part of the flow field.Therefore,we conclude that modern aeroacoustics should merge back into the general unsteady gas dynamics as a special branch of it,with dilatation of multiple sources being a new additional and sharper sound variable.展开更多
文摘A dynamic hierarchical description method for workflow is presented. The method provides a dynamic hierarchical way to define a workflow with non-determinate or dynamic factors. With this method, the main process defined at build-time can be reified and extended by the principle of the sub-organizations at either the build-time or the run-time. To ensure the consistency and integrity of the description, a series of constraint rules are also discussed to realize seamless integration between a decomposed process and its original one. This approach supports the description of unpredictable uncertainties, the dynamic hierarchy of business process, and the dynamic modification of enterprise organizations, and all of these improve the flexibility and extendability of workflow management systems dramatically.
基金supported by the National Natural Science Foundation of China(Grant Nos.12102365,91752202 and 11472016)Luoqin Liu was supported by the Hundred Talents Program of the Chinese Academy of Sciences(CAS).
文摘This paper presents a deep reflection on the advective wave equations for velocity vector and dilatation discovered in the past decade.We show that these equations can form the theoretical basis of modern gas dynamics,because they dominate not only various complex viscous and heat-conducting gas flows but also their associated longitudinal waves,including aero-generated sound.Current aeroacoustics theory has been developing in a manner quite independently of gas dynamics;it is based on the advective wave equations for thermodynamic variables,say the exact Phillips equation of relative disturbance pressure as a representative one.However,these equations do not cover the fluid flow that generates and propagates sound waves.In using them,one has to assume simplified base-flow models,which we argue is the main theoretical obstacle to identifying sound source and achieving effective noise control.Instead,we show that the Phillips equation and alike is nothing but the first integral of the dilatation equation that also governs the longitudinal part of the flow field.Therefore,we conclude that modern aeroacoustics should merge back into the general unsteady gas dynamics as a special branch of it,with dilatation of multiple sources being a new additional and sharper sound variable.