This paper considers a semilinear elliptic equation on a n-dimensional complete noncompact R.iemannian manifold, which is a generalization of the well known Yamabe equation. An existence result is proved.
The most important Moebius invariants in the Moebius differential geometry of submanifolds in S^n＋p are the Moebius metric g, the Moebius second fundamental form B, the Moebius form φ and the Blaschke tensor A. In t...The most important Moebius invariants in the Moebius differential geometry of submanifolds in S^n＋p are the Moebius metric g, the Moebius second fundamental form B, the Moebius form φ and the Blaschke tensor A. In this paper, we obtain the upper bound of the Moebius scalar curvature of submanifolds with parallel Moebius form in S^n＋p.展开更多
A novel frequency hopping(FH) sequences generator based on advanced encryption standard(AES) iterated block cipher is proposed for FH communication systems.The analysis shows that the FH sequences based on AES algorit...A novel frequency hopping(FH) sequences generator based on advanced encryption standard(AES) iterated block cipher is proposed for FH communication systems.The analysis shows that the FH sequences based on AES algorithm have good performance in uniformity, correlation, complexity and security.A high-speed, low-power and low-cost ASIC of FH sequences generator is implemented by optimizing the structure of S-Box and MixColumns of AES algorithm, proposing a hierarchical power management strategy, and applying ...展开更多
The molar heat capacities(C_p) of guaiacol(CAS 90-50-1) and acetyl guaiacol ester(AGE, CAS 613-70-7) were determinated from 290 K to 350 K by differential scanning calorimetry(DSC), and expressed as a function of temp...The molar heat capacities(C_p) of guaiacol(CAS 90-50-1) and acetyl guaiacol ester(AGE, CAS 613-70-7) were determinated from 290 K to 350 K by differential scanning calorimetry(DSC), and expressed as a function of temperature. Two kinds of group contribution models were used to estimate the molar heat capacities of both guaiacol and AGE, the average relative deviation is less than 10%. The standard molar enthalpies of combustion of guaiacol and AGE were- 3590.0 k J·mol^(-1)and- 4522.1 k J·mol^(-1) by a precise thermal isolation Oxygen Bomb Calorimeter. The standard molar enthalpies of formation of guaiacol and AGE in a liquid state at298.15 K were calculated to be- 307.95 k J·mol^(-1) and- 448.72 k J·mol^(-1), respectively, based on the standard molar enthalpies of combustion. The thermodynamic properties are useful for exploiting the new synthesis method, engineering design and industry production of AGE using guaiacol as a raw material.展开更多
Observational data of the severe typhoon Hagupit are obtained by a 3-dimensional ultrasonic anemometer which is installed on a 100-meter-high meteorological tower located at an islet off the coast of Guangdong.The cha...Observational data of the severe typhoon Hagupit are obtained by a 3-dimensional ultrasonic anemometer which is installed on a 100-meter-high meteorological tower located at an islet off the coast of Guangdong.The characteristics of the extreme wind load parameters for offshore wind turbines under the influence of extreme winds at severe typhoon intensity are analyzed.By comparing the observed data with the results derived from the International Electrotechnical Commission (IEC) standard 61400-1,the applicability of the methods computing extreme wind load parameters in the IEC standard are investigated under typhoon conditions.The results are as follows.(1) The changes of both the offshore extreme gust wind speeds and the extreme wind directions render a "M" shape bi-modal distribution with peak values in the eyewall region of Hagupit.(2) There are significant differences of amplitudes of the observed extreme operating gust wind speeds and extreme wind direction from the results calculated from the IEC standard.(3) The amplitudes of both the extreme operating gust wind speeds and the extreme directions exceed the upper limits of the IEC standard for three standard classes of wind turbines,and the values calculated by IEC standard are much significantly larger than the measured ones.(4) The observed extreme operating gust wind speeds are consistent with the results calculated by the IEC standard when wind turbines are under full or partial workload or cut-off conditions,although the amplitude of extreme wind directions calculated in terms of the IEC standard is larger than that of direct measurements.Measured extreme operating gust wind speeds sometimes exceed the IEC design criteria.展开更多
Two new criterions of adiabaticity and two estimation formulas for backward scattering strength are derived in this paper. Numerical simulation shows that the estimations given here are better than the usual one.
This paper presents a damage identification method that consists of a fusion sensitivity matrix that contains information on dynamic and static responses. Based on natural frequency and static displacement, the study ...This paper presents a damage identification method that consists of a fusion sensitivity matrix that contains information on dynamic and static responses. Based on natural frequency and static displacement, the study defines and considers damage criteria such as 1D and 2D single and fusion load cases. To overcome the lack of sufficient information on damage identification in large-scale structures, the authors consider multiple responses to and objective descriptions of uncertainties and various criteria.According to the finite element model and the structural responses described and measured, the fusion methods and damage criteria treat uncertainty as non-probability intervals. As long as we know the bounds of uncertain parameters, the intervals of the elemental stiffness parameters in undamaged and damaged models can be obtained by interval technology. Two numerical examples—a damage-criteria numerical example and a 5-span with 25-bar truss structure in a space solar power station—are proposed. Both examples indicate the veracity of the interval method.展开更多
文摘This paper considers a semilinear elliptic equation on a n-dimensional complete noncompact R.iemannian manifold, which is a generalization of the well known Yamabe equation. An existence result is proved.
基金Supported by the NSF of China(10671087)Supported by the NSF of Jiangxi Province(2008GZS0024)
文摘The most important Moebius invariants in the Moebius differential geometry of submanifolds in S^n＋p are the Moebius metric g, the Moebius second fundamental form B, the Moebius form φ and the Blaschke tensor A. In this paper, we obtain the upper bound of the Moebius scalar curvature of submanifolds with parallel Moebius form in S^n＋p.
基金Supported by National Natural Science Foundation of China (No.60676053)
文摘A novel frequency hopping(FH) sequences generator based on advanced encryption standard(AES) iterated block cipher is proposed for FH communication systems.The analysis shows that the FH sequences based on AES algorithm have good performance in uniformity, correlation, complexity and security.A high-speed, low-power and low-cost ASIC of FH sequences generator is implemented by optimizing the structure of S-Box and MixColumns of AES algorithm, proposing a hierarchical power management strategy, and applying ...
文摘The molar heat capacities(C_p) of guaiacol(CAS 90-50-1) and acetyl guaiacol ester(AGE, CAS 613-70-7) were determinated from 290 K to 350 K by differential scanning calorimetry(DSC), and expressed as a function of temperature. Two kinds of group contribution models were used to estimate the molar heat capacities of both guaiacol and AGE, the average relative deviation is less than 10%. The standard molar enthalpies of combustion of guaiacol and AGE were- 3590.0 k J·mol^(-1)and- 4522.1 k J·mol^(-1) by a precise thermal isolation Oxygen Bomb Calorimeter. The standard molar enthalpies of formation of guaiacol and AGE in a liquid state at298.15 K were calculated to be- 307.95 k J·mol^(-1) and- 448.72 k J·mol^(-1), respectively, based on the standard molar enthalpies of combustion. The thermodynamic properties are useful for exploiting the new synthesis method, engineering design and industry production of AGE using guaiacol as a raw material.
基金National Natural Science Foundation of China (90715031,40775071)Public Benefit Research Foundation of Ministry of Science and Technology (GYHY200806012)
文摘Observational data of the severe typhoon Hagupit are obtained by a 3-dimensional ultrasonic anemometer which is installed on a 100-meter-high meteorological tower located at an islet off the coast of Guangdong.The characteristics of the extreme wind load parameters for offshore wind turbines under the influence of extreme winds at severe typhoon intensity are analyzed.By comparing the observed data with the results derived from the International Electrotechnical Commission (IEC) standard 61400-1,the applicability of the methods computing extreme wind load parameters in the IEC standard are investigated under typhoon conditions.The results are as follows.(1) The changes of both the offshore extreme gust wind speeds and the extreme wind directions render a "M" shape bi-modal distribution with peak values in the eyewall region of Hagupit.(2) There are significant differences of amplitudes of the observed extreme operating gust wind speeds and extreme wind direction from the results calculated from the IEC standard.(3) The amplitudes of both the extreme operating gust wind speeds and the extreme directions exceed the upper limits of the IEC standard for three standard classes of wind turbines,and the values calculated by IEC standard are much significantly larger than the measured ones.(4) The observed extreme operating gust wind speeds are consistent with the results calculated by the IEC standard when wind turbines are under full or partial workload or cut-off conditions,although the amplitude of extreme wind directions calculated in terms of the IEC standard is larger than that of direct measurements.Measured extreme operating gust wind speeds sometimes exceed the IEC design criteria.
基金The author would like to thank the Precision & Intelligent Laboratory of Tokyo Institute of Technology for their financial support. Part of the work was completed when the author visited there. The author also thanks Prof .E.G. Shang for bringing our in
文摘Two new criterions of adiabaticity and two estimation formulas for backward scattering strength are derived in this paper. Numerical simulation shows that the estimations given here are better than the usual one.
基金supported by the National Natural Science Foundation of China(Grant No.11502278)
文摘This paper presents a damage identification method that consists of a fusion sensitivity matrix that contains information on dynamic and static responses. Based on natural frequency and static displacement, the study defines and considers damage criteria such as 1D and 2D single and fusion load cases. To overcome the lack of sufficient information on damage identification in large-scale structures, the authors consider multiple responses to and objective descriptions of uncertainties and various criteria.According to the finite element model and the structural responses described and measured, the fusion methods and damage criteria treat uncertainty as non-probability intervals. As long as we know the bounds of uncertain parameters, the intervals of the elemental stiffness parameters in undamaged and damaged models can be obtained by interval technology. Two numerical examples—a damage-criteria numerical example and a 5-span with 25-bar truss structure in a space solar power station—are proposed. Both examples indicate the veracity of the interval method.
