A defender–attacker–target problem with non-moving target is considered.This problem is modelled by a pursuit-evasion zero-sum differential game with linear dynamics and quadratic cost functional.In this game,the pu...A defender–attacker–target problem with non-moving target is considered.This problem is modelled by a pursuit-evasion zero-sum differential game with linear dynamics and quadratic cost functional.In this game,the pursuer is the defender,while the evader is the attacker.The objective of the pursuer is to minimise the cost functional,while the evader has two objectives:to maximise the cost functional and to keep a given terminal state inequality constraint.The open-loop saddle point solution of this game is obtained in the case where the transfer functions of the controllers for the defender and the attacker are of arbitrary orders.展开更多
In this paper the basic principle and the problems meriting attention in the design and application of active ear defenders are discussed quantitatively. A feasible structure and its experimental results are given. It...In this paper the basic principle and the problems meriting attention in the design and application of active ear defenders are discussed quantitatively. A feasible structure and its experimental results are given. It is illustrated that the chief significance of ' active ' is to change the mechanical impedance of the ear defender accordingly, and because of this mechanism, the noise attenuation effectiveness in the low frequency range is improved.展开更多
Since the publication of Hemingway’s“Indian Camp”in 1924,many scholars has considered Doctor Adams to be insensitive,cold-hearted,ethically immoral.Some others labeled him as a racist and a sexist.After a scrupulou...Since the publication of Hemingway’s“Indian Camp”in 1924,many scholars has considered Doctor Adams to be insensitive,cold-hearted,ethically immoral.Some others labeled him as a racist and a sexist.After a scrupulous and strenuous close reading together with extensive reviewing and analyzing of relevant references,the author of this paper finds that Uncle George has always been misinterpreted over the time.This paper aims to point out the misunderstanding,misinterpretation or even distortion in the previous researches,in an attempt to defend for Doctor Adams and put the record straight.展开更多
LIU Jie still remembers the challenges she faced in the fight against the AIDS epidemic during her stint as a medical volunteer in Nigeria six years ago. Ironically, it was not the lack of medicine or funding that was...LIU Jie still remembers the challenges she faced in the fight against the AIDS epidemic during her stint as a medical volunteer in Nigeria six years ago. Ironically, it was not the lack of medicine or funding that was the biggest hurdle, but the difficulty in effectively delivering the treatment drugs and services.展开更多
The significance of modern power grids is acknowledged every time there is a major threat. This paper proposes the novel approaches to aid power system planner to improve power grid resilience by making appropriate ha...The significance of modern power grids is acknowledged every time there is a major threat. This paper proposes the novel approaches to aid power system planner to improve power grid resilience by making appropriate hardening strategies against man-made attack or natural hazards. The vulnerability indices are introduced, which return the most vulnerable component in the system based on a tri-level defender-attacker-operator(DAO) interdiction problem which solves iteratively. The output of DAO is the set of hardening strategies that optimally allocated along the network to mitigate the impact of the worst-case damages. By repeating DAO problem based on the proposed algorithm, the various crafted attack is imposed on the system, and the defender's behavior demonstrates how an element is vulnerable to threats. The WSCC 9-bus, IEEE 24-bus, and IEEE 118-bus systems are employed to evaluate the model performance.The counter-intuitive results are proven by the proposed robust hardening strategy, which shows how the hardening strategy should be allocated to improve power network resilience against threats.展开更多
The Irish rebellion of 1798 resulted in many casualties and much damage to property.All historians have agreed that Irish society in the eighteenth century was bitterly divided between a governing minority of English ...The Irish rebellion of 1798 resulted in many casualties and much damage to property.All historians have agreed that Irish society in the eighteenth century was bitterly divided between a governing minority of English Protestant settlers,a similar number of Scottish Presbyterian immigrants,who dominated the province of Ulster,and an oppressed majority of poor Catholics who were the original Celtic settlers of the country,but who had lost their lands and their political influence to these later immigrants.Some historians,however,believe that the principal cause of the rebellion was the economic distress of the Catholic majority.More recently,many scholars have claimed that the leaders of the rebellion were educated Protestant English and Scottish settlers,who resented Britain’s political control of Ireland were greatly influenced by the political principles of the French Revolution of 1789.Some of these historians have also studied how the memory of the 1798 rebellion among Catholic Irishmen across the world eventually enabled the Catholic majority to create an Irish republic in the 1920s that was able to govern two-thirds of the country.展开更多
A much-anticipated law protecting homeowners’ rights is on the horizon Television audiences around the country were shocked on November 21,2009,when national broadcaster China Central Television showed clips of two f...A much-anticipated law protecting homeowners’ rights is on the horizon Television audiences around the country were shocked on November 21,2009,when national broadcaster China Central Television showed clips of two families violently fighting lawenforcement officials who were evicting them from their homes.展开更多
文摘A defender–attacker–target problem with non-moving target is considered.This problem is modelled by a pursuit-evasion zero-sum differential game with linear dynamics and quadratic cost functional.In this game,the pursuer is the defender,while the evader is the attacker.The objective of the pursuer is to minimise the cost functional,while the evader has two objectives:to maximise the cost functional and to keep a given terminal state inequality constraint.The open-loop saddle point solution of this game is obtained in the case where the transfer functions of the controllers for the defender and the attacker are of arbitrary orders.
文摘In this paper the basic principle and the problems meriting attention in the design and application of active ear defenders are discussed quantitatively. A feasible structure and its experimental results are given. It is illustrated that the chief significance of ' active ' is to change the mechanical impedance of the ear defender accordingly, and because of this mechanism, the noise attenuation effectiveness in the low frequency range is improved.
文摘Since the publication of Hemingway’s“Indian Camp”in 1924,many scholars has considered Doctor Adams to be insensitive,cold-hearted,ethically immoral.Some others labeled him as a racist and a sexist.After a scrupulous and strenuous close reading together with extensive reviewing and analyzing of relevant references,the author of this paper finds that Uncle George has always been misinterpreted over the time.This paper aims to point out the misunderstanding,misinterpretation or even distortion in the previous researches,in an attempt to defend for Doctor Adams and put the record straight.
文摘LIU Jie still remembers the challenges she faced in the fight against the AIDS epidemic during her stint as a medical volunteer in Nigeria six years ago. Ironically, it was not the lack of medicine or funding that was the biggest hurdle, but the difficulty in effectively delivering the treatment drugs and services.
文摘The significance of modern power grids is acknowledged every time there is a major threat. This paper proposes the novel approaches to aid power system planner to improve power grid resilience by making appropriate hardening strategies against man-made attack or natural hazards. The vulnerability indices are introduced, which return the most vulnerable component in the system based on a tri-level defender-attacker-operator(DAO) interdiction problem which solves iteratively. The output of DAO is the set of hardening strategies that optimally allocated along the network to mitigate the impact of the worst-case damages. By repeating DAO problem based on the proposed algorithm, the various crafted attack is imposed on the system, and the defender's behavior demonstrates how an element is vulnerable to threats. The WSCC 9-bus, IEEE 24-bus, and IEEE 118-bus systems are employed to evaluate the model performance.The counter-intuitive results are proven by the proposed robust hardening strategy, which shows how the hardening strategy should be allocated to improve power network resilience against threats.
文摘The Irish rebellion of 1798 resulted in many casualties and much damage to property.All historians have agreed that Irish society in the eighteenth century was bitterly divided between a governing minority of English Protestant settlers,a similar number of Scottish Presbyterian immigrants,who dominated the province of Ulster,and an oppressed majority of poor Catholics who were the original Celtic settlers of the country,but who had lost their lands and their political influence to these later immigrants.Some historians,however,believe that the principal cause of the rebellion was the economic distress of the Catholic majority.More recently,many scholars have claimed that the leaders of the rebellion were educated Protestant English and Scottish settlers,who resented Britain’s political control of Ireland were greatly influenced by the political principles of the French Revolution of 1789.Some of these historians have also studied how the memory of the 1798 rebellion among Catholic Irishmen across the world eventually enabled the Catholic majority to create an Irish republic in the 1920s that was able to govern two-thirds of the country.
文摘A much-anticipated law protecting homeowners’ rights is on the horizon Television audiences around the country were shocked on November 21,2009,when national broadcaster China Central Television showed clips of two families violently fighting lawenforcement officials who were evicting them from their homes.
