We performed a long range acoustic propagation experiment in the South China Sea(SCS) in November 2004.The environment of the experiment was with an isothermal sound speed profile,where influence of water volume fluct...We performed a long range acoustic propagation experiment in the South China Sea(SCS) in November 2004.The environment of the experiment was with an isothermal sound speed profile,where influence of water volume fluctuation was small,meaning that bottom parameters can be well estimated from acoustic signals.We inverted the acoustic parameters of sediment by using a hybrid inversion scheme that combines the matched field processing inversion with Hamilton sediment empirical relationship and transmission loss data.The numerical results show excellent agreement with the experiment data,indicating validity of the inverted parameters.展开更多
The marine environment provides rich and varied resources and services or functions for human’s produc-tion and life. Many countries have competitively exploited and utilized sea and ocean to develop marine economy f...The marine environment provides rich and varied resources and services or functions for human’s produc-tion and life. Many countries have competitively exploited and utilized sea and ocean to develop marine economy for someyears. The over-exploitation of marine environment and the overuse of marine resources have led to resource degradation,environmental pollution and ecosystem destruction. Considering the depletion of coastal environmental resources dur-ing planning, governing and decision-making is an important measure to promote the harmonious and sustainabledevelopment of coastal environmental resources and social economy, the main precondition of which is that the depletionof coastal environmental resources by human activities has been monetarily evaluated. Firstly, this paper summarizesrelevant references in this field and analyzes different sorts of depletion of coastal environmental resources caused byhuman activities and the necessity and importance of the monetary evaluation. Finally, this paper extensively discussesthe corresponding evaluation models of the depletion of marine mineral resources, marine organism resources, mari-time transport resources, intertidal zones and shallow seas, and marine environmental functions and services includingenvironmental capacity, gas regulation, disturbance prevention, recreation and biodiversity.展开更多
This paper proposes an extended-flux model with core-loss resistance of SynRMs （synchronous reluctance motors） and precise torque estimation without core-loss measurement and position encoder. The proposed torque es...This paper proposes an extended-flux model with core-loss resistance of SynRMs （synchronous reluctance motors） and precise torque estimation without core-loss measurement and position encoder. The proposed torque estimation is useful for precise MTPA （maximum torque per ampere） control of position sensorless controlled SynRMs, which is achieved with the assistance of active and reactive powers.展开更多
基金Supported by the Knowledge Innovation Program of the Chinese Academy of Sciences (No.KZCX1-YW-12-02)the National Natural Science Foundation of China (Nos.10974218 and 10734100)
文摘We performed a long range acoustic propagation experiment in the South China Sea(SCS) in November 2004.The environment of the experiment was with an isothermal sound speed profile,where influence of water volume fluctuation was small,meaning that bottom parameters can be well estimated from acoustic signals.We inverted the acoustic parameters of sediment by using a hybrid inversion scheme that combines the matched field processing inversion with Hamilton sediment empirical relationship and transmission loss data.The numerical results show excellent agreement with the experiment data,indicating validity of the inverted parameters.
基金supported by National Natural Science Foundation of China(Grant No.70371020)Natural Science Foundation of Fujian Province(Grant No.D0410005).
文摘The marine environment provides rich and varied resources and services or functions for human’s produc-tion and life. Many countries have competitively exploited and utilized sea and ocean to develop marine economy for someyears. The over-exploitation of marine environment and the overuse of marine resources have led to resource degradation,environmental pollution and ecosystem destruction. Considering the depletion of coastal environmental resources dur-ing planning, governing and decision-making is an important measure to promote the harmonious and sustainabledevelopment of coastal environmental resources and social economy, the main precondition of which is that the depletionof coastal environmental resources by human activities has been monetarily evaluated. Firstly, this paper summarizesrelevant references in this field and analyzes different sorts of depletion of coastal environmental resources caused byhuman activities and the necessity and importance of the monetary evaluation. Finally, this paper extensively discussesthe corresponding evaluation models of the depletion of marine mineral resources, marine organism resources, mari-time transport resources, intertidal zones and shallow seas, and marine environmental functions and services includingenvironmental capacity, gas regulation, disturbance prevention, recreation and biodiversity.
文摘This paper proposes an extended-flux model with core-loss resistance of SynRMs （synchronous reluctance motors） and precise torque estimation without core-loss measurement and position encoder. The proposed torque estimation is useful for precise MTPA （maximum torque per ampere） control of position sensorless controlled SynRMs, which is achieved with the assistance of active and reactive powers.
