Structural stabilization by a pressurized fluid is very common in nature, however hardly found in technology. Car tires, hot air balloons, airships and airhouses are among the few technical exceptions, which are stab...Structural stabilization by a pressurized fluid is very common in nature, however hardly found in technology. Car tires, hot air balloons, airships and airhouses are among the few technical exceptions, which are stabilized by a compressed medium, typically air. Restricted by simple geometries and a very limited load bearing capacity these pneumatic structures could succeed only in very specialized applications. Nevertheless, prospective concepts ag has systematically investigated pneumatic structures during the last few years. As a major result, it was demonstrated that almost any shape can be made with pneumatic structures and that astonishing structures such as the pneumatic airplane Stingray can be realized even with low air pressure. On top of that, Airlight Ltd. in close collaboration with prospective concepts ag has recently developed the fundamental new structural concept Tensairity. The synergetic combination of an inflated structure with conventional structural elements such as cables and struts yields pneumatic light-weight structures with the load bearing capacity of steel girders. Thus, complex forms and high strength open up many new opportunities for pressure induced stability in technology. An overview of these recent developments is presented and the close relationship of pneumatic structures with biology is outlined.展开更多
A wheat breeding model for high yield in the middle and south of Hebei Province was developed. Wheat variety Ji 84-5418 has been bred on this model. The analysis results of high-yield and stability indicated that Ji 8...A wheat breeding model for high yield in the middle and south of Hebei Province was developed. Wheat variety Ji 84-5418 has been bred on this model. The analysis results of high-yield and stability indicated that Ji 84-5418 was not only an aggregate of varied excellent characters,but a recombined biotype which could early differentiate spike and develop coordi-nately,and had better self-regulation ability and potential high productivity. Its yield is stable at 6000-8250 kg/ha.展开更多
A hybrid remotely operated underwater vehicle( HROV) capable of working to the full ocean depth has been developed. In order for the vehicle to achieve a certain survivability level,a self-repairing control system( SR...A hybrid remotely operated underwater vehicle( HROV) capable of working to the full ocean depth has been developed. In order for the vehicle to achieve a certain survivability level,a self-repairing control system( SRCS) has been designed. It consists of two basic technologies,fault diagnosis and isolation( FDI) and reconfigurable control. For FDI,a model-based hierarchical fault diagnosis system is designed for the HROV. Then,control strategies which reconfigure the control system at intervals according to information from the FDI system are presented. Combining the two technologies,it can obtain the fundamental frame of SRCS for the HROV. Considering the hazardous underwater environment at the limiting depth and the hybrid operating modes,an assessment of the HROV's survivability is vitally needed before it enters operational service. This paper presents a new definition of survivability for underwater vehicles and develops a simple survivability model for the SRCS. As a result of survivability assessment for the SRCS,we are able to figure out the survivability of SRCS and make further optimization about it. The methodology developed herein is also applicable to other types of underwater vehicles.展开更多
The thesis underscores the significant role of human capital in elevating rural self-development ability.The investment of human capital is making great contribution to western rural economic growth,and it plays an ir...The thesis underscores the significant role of human capital in elevating rural self-development ability.The investment of human capital is making great contribution to western rural economic growth,and it plays an irreplaceable role in promoting the socio-economic development prominently.The characteristics of human resources development in western rural areas for the moment are analyzed as follows:the employment structure is simple;the structure of human resources is irrational;the shortage of human resources aggregate is accompanied by the critical phenomenon of idling;the human resources drain badly;there is low input and low output of talents.The thesis also propounds the fundamental approaches in order to elevating self-development ability of western rural areas:we should practise and implement National Medium and Long-term Planning of Talents Development and lay down as soon as possible the detailed matching policies and measures based on the reality of western rural areas;we should develop the education in western rural areas vigorously,and formulate the developmental strategies of bridging "knowledge gap";we should establish sound rural human resources development system,and reinforce the degree of training returning-home migrant workers;we should adjust the structure of human investment timely as needed,and strengthen the degree of human capital investment conspicuously.展开更多
Objective: To explore the effects of self-directed learning readiness and learning attitude on problem-solving ability among Chinese undergraduate nursing students. Methods: A convenience sampling of 460 undergraduate...Objective: To explore the effects of self-directed learning readiness and learning attitude on problem-solving ability among Chinese undergraduate nursing students. Methods: A convenience sampling of 460 undergraduate nursing students was surveyed in Tianjin, China. Students who participated in the study completed a questionnaire that included social demographic questionnaire, Self-directed Learning Readiness Scale, Attitude to Learning Scale, and Social Problem-Solving Inventory. Pearson’s correlation analysis was performed to test the correlations among problem-solving ability, self-directed learning readiness, and learning attitude. Hierarchical linear regression analyses were performed to explore the mediating role of learning attitude. Results: The results showed that learning attitude (r=0.338, P<0.01) and self-directed learning readiness (r=0.493, P<0.01) were positively correlated with problem-solving ability. Learning attitude played a partial intermediary role between self-directed learning readiness and problem-solving ability (F=74.227, P<0.01). Conclusions: It is concluded that nursing educators should pay attention on students’ individual differences and take proper actions to inspire students’ self-directed learning readiness and learning attitude.展开更多
文摘Structural stabilization by a pressurized fluid is very common in nature, however hardly found in technology. Car tires, hot air balloons, airships and airhouses are among the few technical exceptions, which are stabilized by a compressed medium, typically air. Restricted by simple geometries and a very limited load bearing capacity these pneumatic structures could succeed only in very specialized applications. Nevertheless, prospective concepts ag has systematically investigated pneumatic structures during the last few years. As a major result, it was demonstrated that almost any shape can be made with pneumatic structures and that astonishing structures such as the pneumatic airplane Stingray can be realized even with low air pressure. On top of that, Airlight Ltd. in close collaboration with prospective concepts ag has recently developed the fundamental new structural concept Tensairity. The synergetic combination of an inflated structure with conventional structural elements such as cables and struts yields pneumatic light-weight structures with the load bearing capacity of steel girders. Thus, complex forms and high strength open up many new opportunities for pressure induced stability in technology. An overview of these recent developments is presented and the close relationship of pneumatic structures with biology is outlined.
文摘A wheat breeding model for high yield in the middle and south of Hebei Province was developed. Wheat variety Ji 84-5418 has been bred on this model. The analysis results of high-yield and stability indicated that Ji 84-5418 was not only an aggregate of varied excellent characters,but a recombined biotype which could early differentiate spike and develop coordi-nately,and had better self-regulation ability and potential high productivity. Its yield is stable at 6000-8250 kg/ha.
基金Sponsored by the National Natural Science Foundation of China(Grant No.51109132)Specialized Research Fund for the Doctoral Program of Higher Education of China(Grant No.20110073120015)
文摘A hybrid remotely operated underwater vehicle( HROV) capable of working to the full ocean depth has been developed. In order for the vehicle to achieve a certain survivability level,a self-repairing control system( SRCS) has been designed. It consists of two basic technologies,fault diagnosis and isolation( FDI) and reconfigurable control. For FDI,a model-based hierarchical fault diagnosis system is designed for the HROV. Then,control strategies which reconfigure the control system at intervals according to information from the FDI system are presented. Combining the two technologies,it can obtain the fundamental frame of SRCS for the HROV. Considering the hazardous underwater environment at the limiting depth and the hybrid operating modes,an assessment of the HROV's survivability is vitally needed before it enters operational service. This paper presents a new definition of survivability for underwater vehicles and develops a simple survivability model for the SRCS. As a result of survivability assessment for the SRCS,we are able to figure out the survivability of SRCS and make further optimization about it. The methodology developed herein is also applicable to other types of underwater vehicles.
基金Supported by The Subject of Rural Development Center in Sichuan Province(CR1023)The Institute-level Fund of Institute of Political Science and Law,Sichuan Agricultural University
文摘The thesis underscores the significant role of human capital in elevating rural self-development ability.The investment of human capital is making great contribution to western rural economic growth,and it plays an irreplaceable role in promoting the socio-economic development prominently.The characteristics of human resources development in western rural areas for the moment are analyzed as follows:the employment structure is simple;the structure of human resources is irrational;the shortage of human resources aggregate is accompanied by the critical phenomenon of idling;the human resources drain badly;there is low input and low output of talents.The thesis also propounds the fundamental approaches in order to elevating self-development ability of western rural areas:we should practise and implement National Medium and Long-term Planning of Talents Development and lay down as soon as possible the detailed matching policies and measures based on the reality of western rural areas;we should develop the education in western rural areas vigorously,and formulate the developmental strategies of bridging "knowledge gap";we should establish sound rural human resources development system,and reinforce the degree of training returning-home migrant workers;we should adjust the structure of human investment timely as needed,and strengthen the degree of human capital investment conspicuously.
文摘Objective: To explore the effects of self-directed learning readiness and learning attitude on problem-solving ability among Chinese undergraduate nursing students. Methods: A convenience sampling of 460 undergraduate nursing students was surveyed in Tianjin, China. Students who participated in the study completed a questionnaire that included social demographic questionnaire, Self-directed Learning Readiness Scale, Attitude to Learning Scale, and Social Problem-Solving Inventory. Pearson’s correlation analysis was performed to test the correlations among problem-solving ability, self-directed learning readiness, and learning attitude. Hierarchical linear regression analyses were performed to explore the mediating role of learning attitude. Results: The results showed that learning attitude (r=0.338, P<0.01) and self-directed learning readiness (r=0.493, P<0.01) were positively correlated with problem-solving ability. Learning attitude played a partial intermediary role between self-directed learning readiness and problem-solving ability (F=74.227, P<0.01). Conclusions: It is concluded that nursing educators should pay attention on students’ individual differences and take proper actions to inspire students’ self-directed learning readiness and learning attitude.
