The communications industrial standard YD/T 1885-2009 provides the types of headset interfaces, the performance requirements and test methods. Since the release of this standard, more and more manufacturers have adopt...The communications industrial standard YD/T 1885-2009 provides the types of headset interfaces, the performance requirements and test methods. Since the release of this standard, more and more manufacturers have adopted the concentric connector, which gives more choices to consumers and also has benefits on the environmental protection and the healthy development of the mobile terminal industry. Now, the universal headset interface has been included in the draft ITU-T recommendation P.381. lts internationalization will further enhance the universality of the mobile phone headset interlace. It is China＇s another great contribution to the international standardization following the standard of universal power adapter for mobile phones.展开更多
Viscoelastic flows play an important role in numerous engineering fields,and the multiscale algorithms for simulating viscoelastic flows have received significant attention in order to deepen our understanding of the ...Viscoelastic flows play an important role in numerous engineering fields,and the multiscale algorithms for simulating viscoelastic flows have received significant attention in order to deepen our understanding of the nonlinear dynamic behaviors of viscoelastic fluids.However,traditional grid-based multiscale methods are confined to simple viscoelastic flows with short relaxation time,and there is a lack of uniform multiscale scheme available for coupling different solvers in the simulations of viscoelastic fluids.In this paper,a universal multiscale method coupling an improved smoothed particle hydrodynamics(SPH)and multiscale universal interface(MUI)library is presented for viscoelastic flows.The proposed multiscale method builds on an improved SPH method and leverages the MUI library to facilitate the exchange of information among different solvers in the overlapping domain.We test the capability and flexibility of the presented multiscale method to deal with complex viscoelastic flows by solving different multiscale problems of viscoelastic flows.In the first example,the simulation of a viscoelastic Poiseuille flow is carried out by two coupled improved SPH methods with different spatial resolutions.The effects of exchanging different physical quantities on the numerical results in both the upper and lower domains are also investigated as well as the absolute errors in the overlapping domain.In the second example,the complex Wannier flow with different Weissenberg numbers is further simulated by two improved SPH methods and coupling the improved SPH method and the dissipative particle dynamics(DPD)method.The numerical results show that the physical quantities for viscoelastic flows obtained by the presented multiscale method are in consistence with those obtained by a single solver in the overlapping domain.Moreover,transferring different physical quantities has an important effect on the numerical results.展开更多
This paper briefly analyzes the present situation of textile mill＇s air-conditioning system. Since it is difficult to establish detailed math model to control a textile mill＇s airconditioning system because of the i...This paper briefly analyzes the present situation of textile mill＇s air-conditioning system. Since it is difficult to establish detailed math model to control a textile mill＇s airconditioning system because of the influence of various factors such as the differences in seasons, regions, etc., most air-conditioning equipment can not be controlled automatically. This paper suggests utilizing multi-function data acquisRion card to collect the data about the temperature and humidity of a workshop, processing the data on a PC, comparing them with the expert database, and then using the 485 serial port expanding module to output the parameters, which are used to control the inverter, so that the purpose of adjusting the temperature and humidity of the workshop is achieved.展开更多
文摘The communications industrial standard YD/T 1885-2009 provides the types of headset interfaces, the performance requirements and test methods. Since the release of this standard, more and more manufacturers have adopted the concentric connector, which gives more choices to consumers and also has benefits on the environmental protection and the healthy development of the mobile terminal industry. Now, the universal headset interface has been included in the draft ITU-T recommendation P.381. lts internationalization will further enhance the universality of the mobile phone headset interlace. It is China＇s another great contribution to the international standardization following the standard of universal power adapter for mobile phones.
基金Project supported by the National Natural Science Foundation of China(No.52109068)the Water Conservancy Technology Project of Jiangsu Province of China(No.2022060)。
文摘Viscoelastic flows play an important role in numerous engineering fields,and the multiscale algorithms for simulating viscoelastic flows have received significant attention in order to deepen our understanding of the nonlinear dynamic behaviors of viscoelastic fluids.However,traditional grid-based multiscale methods are confined to simple viscoelastic flows with short relaxation time,and there is a lack of uniform multiscale scheme available for coupling different solvers in the simulations of viscoelastic fluids.In this paper,a universal multiscale method coupling an improved smoothed particle hydrodynamics(SPH)and multiscale universal interface(MUI)library is presented for viscoelastic flows.The proposed multiscale method builds on an improved SPH method and leverages the MUI library to facilitate the exchange of information among different solvers in the overlapping domain.We test the capability and flexibility of the presented multiscale method to deal with complex viscoelastic flows by solving different multiscale problems of viscoelastic flows.In the first example,the simulation of a viscoelastic Poiseuille flow is carried out by two coupled improved SPH methods with different spatial resolutions.The effects of exchanging different physical quantities on the numerical results in both the upper and lower domains are also investigated as well as the absolute errors in the overlapping domain.In the second example,the complex Wannier flow with different Weissenberg numbers is further simulated by two improved SPH methods and coupling the improved SPH method and the dissipative particle dynamics(DPD)method.The numerical results show that the physical quantities for viscoelastic flows obtained by the presented multiscale method are in consistence with those obtained by a single solver in the overlapping domain.Moreover,transferring different physical quantities has an important effect on the numerical results.
文摘This paper briefly analyzes the present situation of textile mill＇s air-conditioning system. Since it is difficult to establish detailed math model to control a textile mill＇s airconditioning system because of the influence of various factors such as the differences in seasons, regions, etc., most air-conditioning equipment can not be controlled automatically. This paper suggests utilizing multi-function data acquisRion card to collect the data about the temperature and humidity of a workshop, processing the data on a PC, comparing them with the expert database, and then using the 485 serial port expanding module to output the parameters, which are used to control the inverter, so that the purpose of adjusting the temperature and humidity of the workshop is achieved.
