Introducing the development background and essential aspects of Betty Newman's system model,and exploring the application status of the theory all over the worldwide.This review points out that combining the theor...Introducing the development background and essential aspects of Betty Newman's system model,and exploring the application status of the theory all over the worldwide.This review points out that combining the theoretical model with nursing practice can effectively improve patients'disease self-management ability and improve the quality of life.At the same time,the theory has certain similarities with traditional Chinese medicine nursing,and can provide reference for the development of Chinese medicine nursing theory.展开更多
The distribution of monthly mean error of NMC model forecasts and its seasonal variation are investi- gated.The ratio of monthly mean error to standard deviation is used here to find out that the region where a correc...The distribution of monthly mean error of NMC model forecasts and its seasonal variation are investi- gated.The ratio of monthly mean error to standard deviation is used here to find out that the region where a correction of systematic error is needed and appropriate is mainly in low latitudes.The improvement,after the model's vertical resolution and some physical parameters were changed from April 1985,is investigated,and the NMC operational model forecasts have also compared with those of ECMWF.展开更多
It is proved in this paper that NWP systematic forecast errors in the zonal mean circulation are due to the difference in westerly acceleration process during the forecasting period between model and real atmospheres....It is proved in this paper that NWP systematic forecast errors in the zonal mean circulation are due to the difference in westerly acceleration process during the forecasting period between model and real atmospheres. Those forcing factors which evoke the zonal mean wind variation can be split into various linear terms according to the non-acceleration theorem in a primitive equation system,By applying this tech- nique to the diagnosis of the forecast produets of the T42L9 model in January 1992 and in July 1992, it is indicated that the model has the ability to forecast the zonal mean wind to a reasonable extent, but there are still some errors in several places,especially in the upper troposphere and lower strato- sphere in the mid-latitude region as well as near the surface.The results of analysis by employing this scheme reveal the reason responsible for the systematic forecast errors of the zonal mean wind in the model and the possible way of improving it. It is also shown that non-acceleration theorem can be used as an efficient tool to diagnose the physical processes of NWP models.展开更多
An armored face conveyor(AFC) is a key piece of equipment for a fully mechanized long-wall mining system and is currently the only means for transporting bulk material in hard coal mines. To date, the AFC power train ...An armored face conveyor(AFC) is a key piece of equipment for a fully mechanized long-wall mining system and is currently the only means for transporting bulk material in hard coal mines. To date, the AFC power train design has mainly been based on heuristics obtained via experience, coupled with simple calculations, which cannot take the dynamic behaviors and coupling effects of the components into consideration. Therefore, model-based and simulation-driven design is preferred. In this paper, a new design and analysis methodology for an AFC power train is presented to achieve the optimal dynamic characteristics and transmission performance. A preliminary design procedure for a power train is first introduced. Then, a system-level hydro-mechatronic model of the power train is built to evaluate and optimize the preliminary scheme. Sub-models, including those for the motors, fluid couplers, gearboxes, and chain, are obtained according to their individual disciplines and assembled to form the system-level model. The chain sub-system is discretized into multiple finite elements. Governing equations are established for each element based on the Newton Euler approach and assembled according to the topological structure of the chain system. In order to make the new approach applicable for engineers, a design and analysis software is developed, with a graphical user interface that involves the whole design process. MATLAB/SIMULINK is used as the computational engine, and Visual C++ is adopted to develop the interactive software framework. Simulations for the SGZ1000/2000 type AFC are provided as an illustrative case study to validate the effectiveness and practicality of the model and software package.展开更多
文摘Introducing the development background and essential aspects of Betty Newman's system model,and exploring the application status of the theory all over the worldwide.This review points out that combining the theoretical model with nursing practice can effectively improve patients'disease self-management ability and improve the quality of life.At the same time,the theory has certain similarities with traditional Chinese medicine nursing,and can provide reference for the development of Chinese medicine nursing theory.
文摘The distribution of monthly mean error of NMC model forecasts and its seasonal variation are investi- gated.The ratio of monthly mean error to standard deviation is used here to find out that the region where a correction of systematic error is needed and appropriate is mainly in low latitudes.The improvement,after the model's vertical resolution and some physical parameters were changed from April 1985,is investigated,and the NMC operational model forecasts have also compared with those of ECMWF.
文摘It is proved in this paper that NWP systematic forecast errors in the zonal mean circulation are due to the difference in westerly acceleration process during the forecasting period between model and real atmospheres. Those forcing factors which evoke the zonal mean wind variation can be split into various linear terms according to the non-acceleration theorem in a primitive equation system,By applying this tech- nique to the diagnosis of the forecast produets of the T42L9 model in January 1992 and in July 1992, it is indicated that the model has the ability to forecast the zonal mean wind to a reasonable extent, but there are still some errors in several places,especially in the upper troposphere and lower strato- sphere in the mid-latitude region as well as near the surface.The results of analysis by employing this scheme reveal the reason responsible for the systematic forecast errors of the zonal mean wind in the model and the possible way of improving it. It is also shown that non-acceleration theorem can be used as an efficient tool to diagnose the physical processes of NWP models.
基金supported by the National Natural Science Foundation of China(Grant No.51375330)the Leading Talent Project of Guangdong Province
文摘An armored face conveyor(AFC) is a key piece of equipment for a fully mechanized long-wall mining system and is currently the only means for transporting bulk material in hard coal mines. To date, the AFC power train design has mainly been based on heuristics obtained via experience, coupled with simple calculations, which cannot take the dynamic behaviors and coupling effects of the components into consideration. Therefore, model-based and simulation-driven design is preferred. In this paper, a new design and analysis methodology for an AFC power train is presented to achieve the optimal dynamic characteristics and transmission performance. A preliminary design procedure for a power train is first introduced. Then, a system-level hydro-mechatronic model of the power train is built to evaluate and optimize the preliminary scheme. Sub-models, including those for the motors, fluid couplers, gearboxes, and chain, are obtained according to their individual disciplines and assembled to form the system-level model. The chain sub-system is discretized into multiple finite elements. Governing equations are established for each element based on the Newton Euler approach and assembled according to the topological structure of the chain system. In order to make the new approach applicable for engineers, a design and analysis software is developed, with a graphical user interface that involves the whole design process. MATLAB/SIMULINK is used as the computational engine, and Visual C++ is adopted to develop the interactive software framework. Simulations for the SGZ1000/2000 type AFC are provided as an illustrative case study to validate the effectiveness and practicality of the model and software package.
