The present practice in Bangladesh for erection of girders is placing the girder directly on the bearing pad and joining the adjacent two spans in deck slab level by adopting expansion joints, as the bridges are prese...The present practice in Bangladesh for erection of girders is placing the girder directly on the bearing pad and joining the adjacent two spans in deck slab level by adopting expansion joints, as the bridges are presently designed as simply-supported beam bridge. The main disadvantage of this type of bridges is that, the seismic resistance is weak, and under the external force beyond the design range, the bridges are more likely to fall in danger because of failure in girders. Also they have expansion joints for each span, which affects the comfort of driving and the overall integrity of the bridge deck is poor [1]. Therefore, design and construction of the bridges have been revised to establish continuity between girders of two adjacent spans and transform the bridge as simply supported continuous beam bridge [2]. Temporary bearing (sandbox) method is proposed in this paper to solve the system transformation of continuous beam bridges. Design of the temporary bearing is very simple and can be manufactured at site. This method has been proved in construction of Arial Kha Bridge and can be applied for other similar bridges in Bangladesh.展开更多
A continuous wavelet transform(CWT)and globallocal feature(GLF)extraction-based signal classificationalgorithm is proposed to improve the signal classification accuracy.First,the CWT is utilized to generate the timefr...A continuous wavelet transform(CWT)and globallocal feature(GLF)extraction-based signal classificationalgorithm is proposed to improve the signal classification accuracy.First,the CWT is utilized to generate the timefrequency scalogram.Then,the GLF extraction method is proposed to extract features from the time-frequency scalogram.Finally,a classification method based on the support vector machine(SVM)is proposed to classify the extracted features.Experimental results show that the extended binary phase shift keying(EBPSK)bit error rate(BER)of the proposed classification algorithm is1.3x10_5under the environment of additional white Gaussian noise with the signal-to-noise ratio of-3dB,which is24times lower than that of the SVM-based signal classification method.Meanwhile,the BER using the GLF extraction method is13times lower than the one using the global feature extraction method and24times lower than the one using the local feature extraction method.展开更多
Let D<sup>+</sup> be simply connected bounded domain with the boundary ∈C<sub>n<sup>n</sup></sub>;（0【u【1）,D<sup>-</sup>=E\ , D=D<sup>+</sup> ∪D-, we c...Let D<sup>+</sup> be simply connected bounded domain with the boundary ∈C<sub>n<sup>n</sup></sub>;（0【u【1）,D<sup>-</sup>=E\ , D=D<sup>+</sup> ∪D-, we consider the complex equationwhere A（z） is a n-order continuously differentiable function, and <sup>k</sup> A（z）/az’EL,,z（E）,k=0,1, …,n, p】2. The so-called Riemann type boundary problem of complex equation （1） is to find a piecewise regularsolution w （z） in D, whose boundary value <sup>k</sup>w （t）/ <sup>k</sup>（k=0,1,…,n） continuous on and satisfyingthe boundary展开更多
文摘The present practice in Bangladesh for erection of girders is placing the girder directly on the bearing pad and joining the adjacent two spans in deck slab level by adopting expansion joints, as the bridges are presently designed as simply-supported beam bridge. The main disadvantage of this type of bridges is that, the seismic resistance is weak, and under the external force beyond the design range, the bridges are more likely to fall in danger because of failure in girders. Also they have expansion joints for each span, which affects the comfort of driving and the overall integrity of the bridge deck is poor [1]. Therefore, design and construction of the bridges have been revised to establish continuity between girders of two adjacent spans and transform the bridge as simply supported continuous beam bridge [2]. Temporary bearing (sandbox) method is proposed in this paper to solve the system transformation of continuous beam bridges. Design of the temporary bearing is very simple and can be manufactured at site. This method has been proved in construction of Arial Kha Bridge and can be applied for other similar bridges in Bangladesh.
基金The National Key Technology R&D Program(No.2012BAH15B00)the Scientific Innovation Research of College Graduates in Jiangsu Province(No.KYLX150076)
文摘A continuous wavelet transform(CWT)and globallocal feature(GLF)extraction-based signal classificationalgorithm is proposed to improve the signal classification accuracy.First,the CWT is utilized to generate the timefrequency scalogram.Then,the GLF extraction method is proposed to extract features from the time-frequency scalogram.Finally,a classification method based on the support vector machine(SVM)is proposed to classify the extracted features.Experimental results show that the extended binary phase shift keying(EBPSK)bit error rate(BER)of the proposed classification algorithm is1.3x10_5under the environment of additional white Gaussian noise with the signal-to-noise ratio of-3dB,which is24times lower than that of the SVM-based signal classification method.Meanwhile,the BER using the GLF extraction method is13times lower than the one using the global feature extraction method and24times lower than the one using the local feature extraction method.
文摘Let D<sup>+</sup> be simply connected bounded domain with the boundary ∈C<sub>n<sup>n</sup></sub>;（0【u【1）,D<sup>-</sup>=E\ , D=D<sup>+</sup> ∪D-, we consider the complex equationwhere A（z） is a n-order continuously differentiable function, and <sup>k</sup> A（z）/az’EL,,z（E）,k=0,1, …,n, p】2. The so-called Riemann type boundary problem of complex equation （1） is to find a piecewise regularsolution w （z） in D, whose boundary value <sup>k</sup>w （t）/ <sup>k</sup>（k=0,1,…,n） continuous on and satisfyingthe boundary
