Many factors,such as deck motion and air wave,influence the determination of the approach speed which has an important effect on landing safety. Until recently,there are no design criteria about approach speed of carr...Many factors,such as deck motion and air wave,influence the determination of the approach speed which has an important effect on landing safety. Until recently,there are no design criteria about approach speed of carrier aircraft in the current standards and available publications. Therefore,the requirements of stall margin, longitudinal acceleration ability,altitude correction and field-of-view on approach speed were researched. Based on the flight dynamics model,the flight simulations were conducted to study the effect of the response time of engine,wave off requirements,elevator efficiency and deflection rate on the approach speed. The results presented that the approach longitudinal acceleration and altitude correction ability had crucial influence on the approach speed envelope of the aircraft. The limitations of the control requirements,field- of- view requirements and gear were also given through the simulation and analysis. Based on the above results,the approach speed envelope were determined.展开更多
With the implementation of reform and opening-up, the overall economy of China has made brilliant achievements; meanwhile, however, the economic disparity has been enlarging among some regions, and between the city an...With the implementation of reform and opening-up, the overall economy of China has made brilliant achievements; meanwhile, however, the economic disparity has been enlarging among some regions, and between the city and the countryside. The existence and evolution of this kind of economic disparity is concerned with social stability, sustainable development and the construction of harmonious society, which has gradually become the hotspot in social economic development. The West Coast of the Strait (WCS) located in southeast littoral areas is adjacent to the Pearl and Yangtze River Delta in the south and north and faces Taiwan Province in the east. The stability and development of this region has vital political and economic meaning in the social eco-nomic development of our country. It has important theoretical meaning and practical value to research the form, characteristics and evolution of regional economic disparity in the WCS. Based on insightful analysis on existing study results on the WCS, the paper defines the connotation and extension. By a series of abso-lute and comparative relative evaluation indexes and taking the WCS since 1992 as the study object, the paper makes analysis on different scales including three regions, four regions, 20 cities and 152 counties, quantitatively evaluates the level, characteristics and evolution of the regional economic disparity and compares the regional economic disparity on different scales. The main conclu-sions are as follows: the variation trend of the absolute disparity of the whole region is obvious and stable, which has presented an inflating trend; the comparative variation trend on a large scale has waved, The comparative disparity of the three regions in-creased annually from 1992 to around 2000, which had a decreas-ing trend from around 2000 to 2005; the comparative variation trend on a small scale was not stable, which showed an annual increase of four regions, 20 cities and 152 counties from 1992 to around 2003 and a decrease from around 2003 to 2005; there were some correlations between the regional disparity and scale. In other words, the smaller the scale was, the bigger the disparity was.展开更多
The demands of aircraft quality design criterion on main control system failure and subsequently instantaneous response were analyzed.According to the simulation,the flight characteristics of an aircraft were studied ...The demands of aircraft quality design criterion on main control system failure and subsequently instantaneous response were analyzed.According to the simulation,the flight characteristics of an aircraft were studied in different angle of rudder seizure.It demonstrated that when rudder seizure with high angle and pilot could not take action immediately,the flight parameters would change sharply.The yaw angle increased 50 degrees in 5 minutes,side velocity could attain 40 meters per-second,the angle of attack and sideslip would surpass 30 degrees,roll rate would reach -20 degrees per second,side load would arrive 0.6g.Simultaneity the angle of attack exceeded the limited angle,the aircraft would stall.If control wasn't working,the disaster would happen.These phenomena supply the sufficient information of the rudder malfunction. The validity of correcting yaw moment by asymmetry thrust was testified,the simulation results showed that even rudder seizure in most serious conditions,adopting asymmetry thrust can correct yaw moment caused by the rudder seizure.The judgment standards of flight safety level for the state of malfunction were given.The safety level was assessed caused by the rudder seizure.For an aircraft with two engines on one side,the pilots need to adjust the 4 engines to balance the asymmetric moment,the work load is increased enormously.According the flight safety standards,the safety level is level Ⅲ.展开更多
Regional economic disparity is a hot issue in the development of society and economy.As the conjunct of the Yangtze River Delta and the Pearl River Delta and the frontier to Taiwan,the west coast of the Taiwan Strait(...Regional economic disparity is a hot issue in the development of society and economy.As the conjunct of the Yangtze River Delta and the Pearl River Delta and the frontier to Taiwan,the west coast of the Taiwan Strait(WCS) is of great social and political signif icance.The paper def ines the connotation of the WCS,decomposed the regional economic disparity by using weighted coeff icient of variation and Theil coeff icient,and explores the indus-trial and regional source of the regional economic disparity of the WCS.The analysis results show that:(1) the WCS has important political,economic and military position,so it's better to regard it to be comprehensive region,not just refer to Fujian Province;(2) from the industrial decomposition of weighted variation coeff icient,the influence of the primary industry was tiny;conversely,the development inequity of the secondary and the tertiary industry was the main source of regional economic disparity.Their contribution has had the converse trend and the secondary contri-bution has gone beyond the tertiary since 2003;(3) from the regional decomposition of Theil coeff icient,the regional economic disparity mainly came from inter-area inequity of 4 areas.Moreover,the inner economic disparity mainly drove by Fujian,suggesting that the urban development inequity in Fujian Province was comparatively outstanding.展开更多
文摘Many factors,such as deck motion and air wave,influence the determination of the approach speed which has an important effect on landing safety. Until recently,there are no design criteria about approach speed of carrier aircraft in the current standards and available publications. Therefore,the requirements of stall margin, longitudinal acceleration ability,altitude correction and field-of-view on approach speed were researched. Based on the flight dynamics model,the flight simulations were conducted to study the effect of the response time of engine,wave off requirements,elevator efficiency and deflection rate on the approach speed. The results presented that the approach longitudinal acceleration and altitude correction ability had crucial influence on the approach speed envelope of the aircraft. The limitations of the control requirements,field- of- view requirements and gear were also given through the simulation and analysis. Based on the above results,the approach speed envelope were determined.
文摘With the implementation of reform and opening-up, the overall economy of China has made brilliant achievements; meanwhile, however, the economic disparity has been enlarging among some regions, and between the city and the countryside. The existence and evolution of this kind of economic disparity is concerned with social stability, sustainable development and the construction of harmonious society, which has gradually become the hotspot in social economic development. The West Coast of the Strait (WCS) located in southeast littoral areas is adjacent to the Pearl and Yangtze River Delta in the south and north and faces Taiwan Province in the east. The stability and development of this region has vital political and economic meaning in the social eco-nomic development of our country. It has important theoretical meaning and practical value to research the form, characteristics and evolution of regional economic disparity in the WCS. Based on insightful analysis on existing study results on the WCS, the paper defines the connotation and extension. By a series of abso-lute and comparative relative evaluation indexes and taking the WCS since 1992 as the study object, the paper makes analysis on different scales including three regions, four regions, 20 cities and 152 counties, quantitatively evaluates the level, characteristics and evolution of the regional economic disparity and compares the regional economic disparity on different scales. The main conclu-sions are as follows: the variation trend of the absolute disparity of the whole region is obvious and stable, which has presented an inflating trend; the comparative variation trend on a large scale has waved, The comparative disparity of the three regions in-creased annually from 1992 to around 2000, which had a decreas-ing trend from around 2000 to 2005; the comparative variation trend on a small scale was not stable, which showed an annual increase of four regions, 20 cities and 152 counties from 1992 to around 2003 and a decrease from around 2003 to 2005; there were some correlations between the regional disparity and scale. In other words, the smaller the scale was, the bigger the disparity was.
文摘The demands of aircraft quality design criterion on main control system failure and subsequently instantaneous response were analyzed.According to the simulation,the flight characteristics of an aircraft were studied in different angle of rudder seizure.It demonstrated that when rudder seizure with high angle and pilot could not take action immediately,the flight parameters would change sharply.The yaw angle increased 50 degrees in 5 minutes,side velocity could attain 40 meters per-second,the angle of attack and sideslip would surpass 30 degrees,roll rate would reach -20 degrees per second,side load would arrive 0.6g.Simultaneity the angle of attack exceeded the limited angle,the aircraft would stall.If control wasn't working,the disaster would happen.These phenomena supply the sufficient information of the rudder malfunction. The validity of correcting yaw moment by asymmetry thrust was testified,the simulation results showed that even rudder seizure in most serious conditions,adopting asymmetry thrust can correct yaw moment caused by the rudder seizure.The judgment standards of flight safety level for the state of malfunction were given.The safety level was assessed caused by the rudder seizure.For an aircraft with two engines on one side,the pilots need to adjust the 4 engines to balance the asymmetric moment,the work load is increased enormously.According the flight safety standards,the safety level is level Ⅲ.
文摘Regional economic disparity is a hot issue in the development of society and economy.As the conjunct of the Yangtze River Delta and the Pearl River Delta and the frontier to Taiwan,the west coast of the Taiwan Strait(WCS) is of great social and political signif icance.The paper def ines the connotation of the WCS,decomposed the regional economic disparity by using weighted coeff icient of variation and Theil coeff icient,and explores the indus-trial and regional source of the regional economic disparity of the WCS.The analysis results show that:(1) the WCS has important political,economic and military position,so it's better to regard it to be comprehensive region,not just refer to Fujian Province;(2) from the industrial decomposition of weighted variation coeff icient,the influence of the primary industry was tiny;conversely,the development inequity of the secondary and the tertiary industry was the main source of regional economic disparity.Their contribution has had the converse trend and the secondary contri-bution has gone beyond the tertiary since 2003;(3) from the regional decomposition of Theil coeff icient,the regional economic disparity mainly came from inter-area inequity of 4 areas.Moreover,the inner economic disparity mainly drove by Fujian,suggesting that the urban development inequity in Fujian Province was comparatively outstanding.
