1. Often blacks were not allowed intohotels, schools or libraries at all. (Page 28)【考点】allow的用法【归纳】allow 意为"允许, 准许"。用法有:allow sth. doing sth.allow sb. to do sth.allow sb. sth.allow for +...1. Often blacks were not allowed intohotels, schools or libraries at all. (Page 28)【考点】allow的用法【归纳】allow 意为"允许, 准许"。用法有:allow sth. doing sth.allow sb. to do sth.allow sb. sth.allow for +n. (考虑, 顾及) / doing / obj.+展开更多
Fighters and other complex engineering systems have many characteristics such as difficult modeling and testing, multiple working situations, and high cost. Aim at these points, a new kind of real-time fault predictor...Fighters and other complex engineering systems have many characteristics such as difficult modeling and testing, multiple working situations, and high cost. Aim at these points, a new kind of real-time fault predictor is designed based on an improved k-nearest neighbor method, which needs neither the math model of system nc, the training data and prior knowledge. It can study and predict while system＇s running, so that it can overcome the difficulty of data acquirement. Besides, this predictor has a fast prediction speed, and the false alarm rate and missing alarm rate can be adjusted randomly. The method is simple and universalizable. The result of simulation on fighter F-16 proved the effidency.展开更多
Analyses of the systematic confrontation between two military forcfes are the highest hierarchy on opera-tional effectiveness study of weapon systema.The physi-cal model for tactical many-on-many engagements of an aer...Analyses of the systematic confrontation between two military forcfes are the highest hierarchy on opera-tional effectiveness study of weapon systema.The physi-cal model for tactical many-on-many engagements of an aerial warfare with heterogeneous figher aircraft is estab-lished.On the basis of Lanchester multivariate equations of square law,a mathematical model corresponding to the established physical model is given.A superiorityh parame-ter is then derived directly from the mathematical model.With view to the high -tech condition of modern war-fare,the concept of superiority parameter which more well and truly reflects the essential of an air-to-air en-gagement is further formulated.The attrition coeffi-cients,which are key to the differential equations,are de-termined by using tactics of random target assignment and air-to-air capability index of the fighter aircraft.Hereby,taking the mathematical model and superiority parameter as cores,calculations amd analyses of complicate systemic problems such as evaluation of battle superiority,prog-mostication of combat process and optimization of colloca-tions have been accomplished.Results indicate that a clas-sical combat theory with its certain recent development has received newer applications in the military operation research for complicated confrontation analysis issues.展开更多
In order to realize the real-time and precise test for a weapon system of a certain type of fighter,a signal classification method according to attributes is proposed,common input channels for multiple signals are con...In order to realize the real-time and precise test for a weapon system of a certain type of fighter,a signal classification method according to attributes is proposed,common input channels for multiple signals are configured optimally,and a test adapter and an adaptive signal conditioning module is designed. The hardware of conditioning module can be configured flexibly and the programmable test range can be adjusted owing to programmable multiplexer. An FPGA adaptive filter is designed by the calculated filter coefficient vectors with LMS method to solve the problem of parallel test of fighter weapon system in electromagnetic interference environment. The adaptive signal conditioning technology is characterized by high efficiency,precision and integration. Its application makes the test system successful to conduct real-time and parallel test for a weapon system,which is developed based on VXI bus and virtual-instrument technology.展开更多
An expression of correlating parameter is developed which can be used to synthetically express the close combat maneuverability of fighters by the method of fuzzy mathematics. On the basis of analysis of fighter maneu...An expression of correlating parameter is developed which can be used to synthetically express the close combat maneuverability of fighters by the method of fuzzy mathematics. On the basis of analysis of fighter maneuvering performances, this paper proposes the parameters ωA,ωs, and SEP to measure the maneuvering performances. The linear weighted method, which is one of the basic methods of transforming several objects to a single object in mathematics programming, is used to determine the form of the correlating parameter expression. The focal point of this paper's work is to determine the weight coefficients of maneuvering performances in the expression. In order to solve this problem, the inverse problem of synthetic judgement in fuzzy mathematics is employed. The development of the equation of fuzzy relationship in this paper is based on the judgement data, which are gathered from many experts working in aeronautical field. Therefore, the expression of correlating parameter developed by this paper can be used in the design object at aircraft conceptual design stage and the judgement of synthetical measurement of the maneuverability of fighters.展开更多
一、词语例解1.prison n.1)监狱;牢房He is in prison now.That's why wehaven't seen him for months.他在坐牢,所以我们好几个月没见到他了。It was reported that four men escapedfrom prison yesterday.据报道。
The Potala Palace is situated on the"red"mountain of Lhasa.A group of police fire fighters, unknown to most people,are actually the"guardians of the national treasures"and are living all year aroun...The Potala Palace is situated on the"red"mountain of Lhasa.A group of police fire fighters, unknown to most people,are actually the"guardians of the national treasures"and are living all year around inside the Potala Palace.Seemingly they have formed a consolidated"fireproof wall"to protect this world famous cultural heritage.Since they took up residence 23 years ago, there have been no accidental fires in the palace.展开更多
As one of the seven survival plays of Sophocles of ancient Greece,Oedipus Rex arouses many scholars' interest in Ancient Greek tragedy.Until now there are a lot of critical comments on the great play itself and th...As one of the seven survival plays of Sophocles of ancient Greece,Oedipus Rex arouses many scholars' interest in Ancient Greek tragedy.Until now there are a lot of critical comments on the great play itself and the main character Oedipus himself.The super hero Oedipus blinded his own eyes by his own hands at the end of the play.People showed different views on his behavior.On the basis of different views,this article is going to discuss whether Oedipus is a passive figure or an active fighter at that time.展开更多
Nathaniel Hawthorne,one of the most famous writers in America in 19th century,lived in the circumstance of Puritanism.As the complicated condition in Puritanism,Hawthorne treated it with a complicated attitude.The Sca...Nathaniel Hawthorne,one of the most famous writers in America in 19th century,lived in the circumstance of Puritanism.As the complicated condition in Puritanism,Hawthorne treated it with a complicated attitude.The Scarlet Letter is one of Hawthorne's best novels.Through his positive attitude towards some Biblical principles,we can see his desire for real belief;through the characters'tragedies in The Scarlet Letter,we can see his negative attitude towards Puritanism.This thesis discusses Hawthorne's attitude towards Biblical principles in The Scarlet Letter to show he is a good fighter for Bible.展开更多
The achievement of laminar flow in the boundary layer at high-speed cruise conditions may further, in addition to shock-wave control, reduce the drag and extend the range of military fighter aircraft. To this end, a f...The achievement of laminar flow in the boundary layer at high-speed cruise conditions may further, in addition to shock-wave control, reduce the drag and extend the range of military fighter aircraft. To this end, a further investigation on transitional boundary-layer flow of fighter wings is needed due to different configurations from the wings used on conventional transport aircraft. In this paper, wind tunnel experiments and numerical simulations were conducted on three-dimensional transition of thin diamond-shaped wings used on advanced fighter aircraft at tran/supersonic design points. A newly proposed correlation of crossflow transition which includes the effect of surface roughness was introduced into the c-Rehttransition model. Predicted results were in good agreement with flow visualizations. Results showed that the strength of the crossflow component grew rapidly around the leading edge because of the severe flow acceleration, just as the same as wings with a large aspect ratio. However, there seemed no regular pattern of instabilitydominance variation in span-wise for a diamond configuration. The dominance of different instability mechanisms strongly depended on the local pressure distribution. Hereby, the research recommended a ‘‘roof-like" shape of pressure distribution to suppress both crossflow and Tollmien-Schlichting(T-S) instabilities. Besides, a sharp suction peak with a serious pressure rise should be cut off to avoid stronger instabilities. Further discussions also revealed an independence of the unit Reynolds number when transition was triggered by T-S instabilities. Aerodynamic force comparisons indicated that further benefit on drag reduction could be expected by including the three-dimensional transition effect into a wing design process.展开更多
文摘1. Often blacks were not allowed intohotels, schools or libraries at all. (Page 28)【考点】allow的用法【归纳】allow 意为"允许, 准许"。用法有:allow sth. doing sth.allow sb. to do sth.allow sb. sth.allow for +n. (考虑, 顾及) / doing / obj.+
文摘Fighters and other complex engineering systems have many characteristics such as difficult modeling and testing, multiple working situations, and high cost. Aim at these points, a new kind of real-time fault predictor is designed based on an improved k-nearest neighbor method, which needs neither the math model of system nc, the training data and prior knowledge. It can study and predict while system＇s running, so that it can overcome the difficulty of data acquirement. Besides, this predictor has a fast prediction speed, and the false alarm rate and missing alarm rate can be adjusted randomly. The method is simple and universalizable. The result of simulation on fighter F-16 proved the effidency.
文摘Analyses of the systematic confrontation between two military forcfes are the highest hierarchy on opera-tional effectiveness study of weapon systema.The physi-cal model for tactical many-on-many engagements of an aerial warfare with heterogeneous figher aircraft is estab-lished.On the basis of Lanchester multivariate equations of square law,a mathematical model corresponding to the established physical model is given.A superiorityh parame-ter is then derived directly from the mathematical model.With view to the high -tech condition of modern war-fare,the concept of superiority parameter which more well and truly reflects the essential of an air-to-air en-gagement is further formulated.The attrition coeffi-cients,which are key to the differential equations,are de-termined by using tactics of random target assignment and air-to-air capability index of the fighter aircraft.Hereby,taking the mathematical model and superiority parameter as cores,calculations amd analyses of complicate systemic problems such as evaluation of battle superiority,prog-mostication of combat process and optimization of colloca-tions have been accomplished.Results indicate that a clas-sical combat theory with its certain recent development has received newer applications in the military operation research for complicated confrontation analysis issues.
基金Sponsored by the Key Equipment Research Project of Air Force of China (KJZ06119)
文摘In order to realize the real-time and precise test for a weapon system of a certain type of fighter,a signal classification method according to attributes is proposed,common input channels for multiple signals are configured optimally,and a test adapter and an adaptive signal conditioning module is designed. The hardware of conditioning module can be configured flexibly and the programmable test range can be adjusted owing to programmable multiplexer. An FPGA adaptive filter is designed by the calculated filter coefficient vectors with LMS method to solve the problem of parallel test of fighter weapon system in electromagnetic interference environment. The adaptive signal conditioning technology is characterized by high efficiency,precision and integration. Its application makes the test system successful to conduct real-time and parallel test for a weapon system,which is developed based on VXI bus and virtual-instrument technology.
文摘An expression of correlating parameter is developed which can be used to synthetically express the close combat maneuverability of fighters by the method of fuzzy mathematics. On the basis of analysis of fighter maneuvering performances, this paper proposes the parameters ωA,ωs, and SEP to measure the maneuvering performances. The linear weighted method, which is one of the basic methods of transforming several objects to a single object in mathematics programming, is used to determine the form of the correlating parameter expression. The focal point of this paper's work is to determine the weight coefficients of maneuvering performances in the expression. In order to solve this problem, the inverse problem of synthetic judgement in fuzzy mathematics is employed. The development of the equation of fuzzy relationship in this paper is based on the judgement data, which are gathered from many experts working in aeronautical field. Therefore, the expression of correlating parameter developed by this paper can be used in the design object at aircraft conceptual design stage and the judgement of synthetical measurement of the maneuverability of fighters.
文摘一、词语例解1.prison n.1)监狱;牢房He is in prison now.That's why wehaven't seen him for months.他在坐牢,所以我们好几个月没见到他了。It was reported that four men escapedfrom prison yesterday.据报道。
文摘The Potala Palace is situated on the"red"mountain of Lhasa.A group of police fire fighters, unknown to most people,are actually the"guardians of the national treasures"and are living all year around inside the Potala Palace.Seemingly they have formed a consolidated"fireproof wall"to protect this world famous cultural heritage.Since they took up residence 23 years ago, there have been no accidental fires in the palace.
文摘As one of the seven survival plays of Sophocles of ancient Greece,Oedipus Rex arouses many scholars' interest in Ancient Greek tragedy.Until now there are a lot of critical comments on the great play itself and the main character Oedipus himself.The super hero Oedipus blinded his own eyes by his own hands at the end of the play.People showed different views on his behavior.On the basis of different views,this article is going to discuss whether Oedipus is a passive figure or an active fighter at that time.
文摘Nathaniel Hawthorne,one of the most famous writers in America in 19th century,lived in the circumstance of Puritanism.As the complicated condition in Puritanism,Hawthorne treated it with a complicated attitude.The Scarlet Letter is one of Hawthorne's best novels.Through his positive attitude towards some Biblical principles,we can see his desire for real belief;through the characters'tragedies in The Scarlet Letter,we can see his negative attitude towards Puritanism.This thesis discusses Hawthorne's attitude towards Biblical principles in The Scarlet Letter to show he is a good fighter for Bible.
基金supported by the National Natural Science Foundation of China (No.11372254)
文摘The achievement of laminar flow in the boundary layer at high-speed cruise conditions may further, in addition to shock-wave control, reduce the drag and extend the range of military fighter aircraft. To this end, a further investigation on transitional boundary-layer flow of fighter wings is needed due to different configurations from the wings used on conventional transport aircraft. In this paper, wind tunnel experiments and numerical simulations were conducted on three-dimensional transition of thin diamond-shaped wings used on advanced fighter aircraft at tran/supersonic design points. A newly proposed correlation of crossflow transition which includes the effect of surface roughness was introduced into the c-Rehttransition model. Predicted results were in good agreement with flow visualizations. Results showed that the strength of the crossflow component grew rapidly around the leading edge because of the severe flow acceleration, just as the same as wings with a large aspect ratio. However, there seemed no regular pattern of instabilitydominance variation in span-wise for a diamond configuration. The dominance of different instability mechanisms strongly depended on the local pressure distribution. Hereby, the research recommended a ‘‘roof-like" shape of pressure distribution to suppress both crossflow and Tollmien-Schlichting(T-S) instabilities. Besides, a sharp suction peak with a serious pressure rise should be cut off to avoid stronger instabilities. Further discussions also revealed an independence of the unit Reynolds number when transition was triggered by T-S instabilities. Aerodynamic force comparisons indicated that further benefit on drag reduction could be expected by including the three-dimensional transition effect into a wing design process.
