The impeller of turbo machinery is a typical nonlinear multi-oscillator system.The vibration of each module is coupling, including fluid-solid coupling of the blade.The subject of our investigation was a KDF-5 mine fa...The impeller of turbo machinery is a typical nonlinear multi-oscillator system.The vibration of each module is coupling, including fluid-solid coupling of the blade.The subject of our investigation was a KDF-5 mine fan for which we analyzed air vibration signals and axial vibration signals by using correlation dimension analysis under five variable working conditions.The results indicate that their correlation dimension curves show a uniform trend.That is to say, the characteristics of the variation signals of the integral structure are correlated and mutually embodied.It proves that it is possible to monitor the working state of a mine fan by coupling the vibration signals and air vibration signals for these are more sensitive in representing the status of the impeller system.展开更多
Approximate analytical solutions of the Dirac equation in the case of pseudospin and spin symmetry limits are inves- tigated under the Deng-Fan potential by applying the asymptotic iteration method for the arbitrary q...Approximate analytical solutions of the Dirac equation in the case of pseudospin and spin symmetry limits are inves- tigated under the Deng-Fan potential by applying the asymptotic iteration method for the arbitrary quantum numbers n and ~~. Some of the numerical results are also represented in both pseudospin symmetry and spin symmetry limits.展开更多
Over the last few decades,cross-fertilization between marketing and fandom studies in a mediated world has been rare,hindering the knowledge development for marketing practitioners in the Chinese fan economy context.T...Over the last few decades,cross-fertilization between marketing and fandom studies in a mediated world has been rare,hindering the knowledge development for marketing practitioners in the Chinese fan economy context.The purpose of this study is to find and establish a conceptual framework that includes Online Interaction(OI),Parasocial Relationships(PSR)and virtual fan communities on Weibo,and how these contributory factors embedded in the interplay process of digital fandom practices in terms of enhancing fans’Purchase Intention(PI)and media consumption behaviours toward the celebrities’merchandise.Using an online survey instrument,this research collected 294 completed responses from fans who had online interactions with celebrities and engagement of virtual fan communities on Weibo.Key results and findings provided a clear framework of four antecedents based on the conceptual model and indicated that the high intensity of OI led to higher levels of the perception of PSR and the Sense of Virtual Community(SOVC).Increased PSR and the SOVC can be seen as significant positive predictors of the PI(a part of consumer identity construction as a fan)also.This study revealed the underlying mechanism of an emerging marketing genre,also provide useful implications of audiences’digital marketing practices for marketers,celebrities and policymakers.展开更多
Across the Himalayan foreland area,alluvial fans respond to fluvial depositional landforms created by active tectonics and are incorporated within hydro-sediment processes.Each tributary of the master stream has its w...Across the Himalayan foreland area,alluvial fans respond to fluvial depositional landforms created by active tectonics and are incorporated within hydro-sediment processes.Each tributary of the master stream has its water and sediment to discharge,which assists in initiating several mesolevel fans in response to the active tectonics in Jaldhaka basin.Along the mountain front,active MBT(Main Boundary Thrust),MFT(Main Frontal Thrust)and lineaments(parallel and transverse to Himalaya)have governed the tectonically active Quaternary foreland area where numerous meso-level fans have developed.The study aims to estimate the tectonic activeness of each meso-fan using the morphotectonic indicators.The tributaries of the Jaldhaka River are permuted to the recent tectonism or neotectonics to form each meso fan with its basin displaying the varying degree of their activeness and aggradation system.Statistical methods like technique for order performance by similarity to ideal solution(TOPSIS)and VIKOR(Vlse Kriterijumska Optimizacija Kompromisno Resenje)that specify multicriteria optimization and compromise solution,in Serbian have ranked the Fan 2 as mostly active and Fan 4 is comparatively tectonically stable.The hydro-sediment characteristics reveal the topographic spatial dynamics of Fan 4 where lobe 3 has elevated from 1984-2014.The XRD analysis specifies the scientific key in response to the dominance of dolomite in the aggraded elevated bed sediments carried by the Rohtikhola River.The conceptual fan models of Fan 2and 4 display the fan development phases through four stages.It has clearly defined the extension of the fan lobes of Fan 2 and 4.It is summarized that within a common climatic zone and similar neo-tectonic setting,meso-level fans have differential morphotectonic signatures with dynamic aggradation processes.展开更多
The flow over a short intake is characterised by a strong interaction with the fan, that can only be captured when the rotor blades are modelled in the numerical simulations. In this paper, we use a coupled methodolog...The flow over a short intake is characterised by a strong interaction with the fan, that can only be captured when the rotor blades are modelled in the numerical simulations. In this paper, we use a coupled methodology to derive indications about relevant geometric variables affecting the high-incidence operation of an ultra-high bypass ratio turbofan intake with a length-to-diameter ratio of 0.35. By reproducing the effect of the fan through a body force model, we carry out a parametric study of the influence of the contraction ratio and the scarf angle at take-off conditions for a grid of 28 different three-dimensional shapes. The analysis of the selected performance metrics distributions at three angles of attack of 16., 24., and 28. reveals that a contraction ratio higher than 1.20 is needed to avoid separation at high incidence. While for an attached inlet the best performance is found with a moderate scarf angle, in presence of a developed separation the distortion level reduces as the scarf decreases up to negative values. We discuss the correspondence between the distortion indexes and the flow field, highlighting the origin of the detachment for the different geometries, according to the operating condition, and analysing the fan operation in the most distorted case. Finally, we assess the influence of modelling the rotor in the simulations, showing that its suppression effect on the separation at a given incidence depends on the intake geometric features.展开更多
基金Projects BK2005018 supported by the Natural Science Foundation of Jiangsu Province CX07B-061z by the Graduate Research and Innovation Plan of Jiangsu Province
文摘The impeller of turbo machinery is a typical nonlinear multi-oscillator system.The vibration of each module is coupling, including fluid-solid coupling of the blade.The subject of our investigation was a KDF-5 mine fan for which we analyzed air vibration signals and axial vibration signals by using correlation dimension analysis under five variable working conditions.The results indicate that their correlation dimension curves show a uniform trend.That is to say, the characteristics of the variation signals of the integral structure are correlated and mutually embodied.It proves that it is possible to monitor the working state of a mine fan by coupling the vibration signals and air vibration signals for these are more sensitive in representing the status of the impeller system.
文摘Approximate analytical solutions of the Dirac equation in the case of pseudospin and spin symmetry limits are inves- tigated under the Deng-Fan potential by applying the asymptotic iteration method for the arbitrary quantum numbers n and ~~. Some of the numerical results are also represented in both pseudospin symmetry and spin symmetry limits.
文摘Over the last few decades,cross-fertilization between marketing and fandom studies in a mediated world has been rare,hindering the knowledge development for marketing practitioners in the Chinese fan economy context.The purpose of this study is to find and establish a conceptual framework that includes Online Interaction(OI),Parasocial Relationships(PSR)and virtual fan communities on Weibo,and how these contributory factors embedded in the interplay process of digital fandom practices in terms of enhancing fans’Purchase Intention(PI)and media consumption behaviours toward the celebrities’merchandise.Using an online survey instrument,this research collected 294 completed responses from fans who had online interactions with celebrities and engagement of virtual fan communities on Weibo.Key results and findings provided a clear framework of four antecedents based on the conceptual model and indicated that the high intensity of OI led to higher levels of the perception of PSR and the Sense of Virtual Community(SOVC).Increased PSR and the SOVC can be seen as significant positive predictors of the PI(a part of consumer identity construction as a fan)also.This study revealed the underlying mechanism of an emerging marketing genre,also provide useful implications of audiences’digital marketing practices for marketers,celebrities and policymakers.
文摘Across the Himalayan foreland area,alluvial fans respond to fluvial depositional landforms created by active tectonics and are incorporated within hydro-sediment processes.Each tributary of the master stream has its water and sediment to discharge,which assists in initiating several mesolevel fans in response to the active tectonics in Jaldhaka basin.Along the mountain front,active MBT(Main Boundary Thrust),MFT(Main Frontal Thrust)and lineaments(parallel and transverse to Himalaya)have governed the tectonically active Quaternary foreland area where numerous meso-level fans have developed.The study aims to estimate the tectonic activeness of each meso-fan using the morphotectonic indicators.The tributaries of the Jaldhaka River are permuted to the recent tectonism or neotectonics to form each meso fan with its basin displaying the varying degree of their activeness and aggradation system.Statistical methods like technique for order performance by similarity to ideal solution(TOPSIS)and VIKOR(Vlse Kriterijumska Optimizacija Kompromisno Resenje)that specify multicriteria optimization and compromise solution,in Serbian have ranked the Fan 2 as mostly active and Fan 4 is comparatively tectonically stable.The hydro-sediment characteristics reveal the topographic spatial dynamics of Fan 4 where lobe 3 has elevated from 1984-2014.The XRD analysis specifies the scientific key in response to the dominance of dolomite in the aggraded elevated bed sediments carried by the Rohtikhola River.The conceptual fan models of Fan 2and 4 display the fan development phases through four stages.It has clearly defined the extension of the fan lobes of Fan 2 and 4.It is summarized that within a common climatic zone and similar neo-tectonic setting,meso-level fans have differential morphotectonic signatures with dynamic aggradation processes.
文摘The flow over a short intake is characterised by a strong interaction with the fan, that can only be captured when the rotor blades are modelled in the numerical simulations. In this paper, we use a coupled methodology to derive indications about relevant geometric variables affecting the high-incidence operation of an ultra-high bypass ratio turbofan intake with a length-to-diameter ratio of 0.35. By reproducing the effect of the fan through a body force model, we carry out a parametric study of the influence of the contraction ratio and the scarf angle at take-off conditions for a grid of 28 different three-dimensional shapes. The analysis of the selected performance metrics distributions at three angles of attack of 16., 24., and 28. reveals that a contraction ratio higher than 1.20 is needed to avoid separation at high incidence. While for an attached inlet the best performance is found with a moderate scarf angle, in presence of a developed separation the distortion level reduces as the scarf decreases up to negative values. We discuss the correspondence between the distortion indexes and the flow field, highlighting the origin of the detachment for the different geometries, according to the operating condition, and analysing the fan operation in the most distorted case. Finally, we assess the influence of modelling the rotor in the simulations, showing that its suppression effect on the separation at a given incidence depends on the intake geometric features.