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The purpose of this paper is to study the seismic performance of the energy-saving block and invisible multi-ribbed frame composite walls (EBIMFCW), changing the shear-span ratio as the test parameter, the low-cycle reciprocating loading tests of six 1/2 scale wall models were carried out.

The test design method and analysis are used for the seismic performance of the EBIMFCW.

With the increase of shear-span ratio: the walls tend to occur bending failure even more, the initial stiffness of the wall decreases, the overall ductility of the wall is improved and the walls tend to occur bending failure.

The previous studies do not involve the seismic performance of EBIMFCW under different shear-span ratios. Therefore, the paper studies the hysteresis behavior, ductility, stiffness degradation and energy dissipation performance of EBIMFCW under different shear-span ratios.

The purpose of this paper is to investigate the equivalent control authority of the conventional and circulation control (CC) wing of the aircraft and assess the energy expenditure and aerodynamic efficiency of the CC wing.

Four target cases with different flap deflection angles θ are set in advance for the conventional wing, and then a series of cases with different jet momentum coefficients Cμ are set for the CC wing. The lift, drag and momentum coefficient curves of the CC wing are compared to those of the four conventional wing cases. The curves with the best agreement are selected to establish the corresponding relation between θ and Cμ. The energy expenditure of the CC system is analyzed. The concept of equivalent lift-to-drag ratio for the CC wing is introduced to compare the aerodynamic efficiency with the conventional wing

The control authority of the conventional wing at θ = 0º, 10º, 20º, 30º are equivalent to the control authority of the CC wing with Cµ = 0.0, 0.005, 0.009 and 0.012. The CC system is more efficient at small Cµ than large Cµ.

This study could contribute to the application of the CC system on flapless aircrafts.

The corresponding relation between θ and Cµ is established by matching the equivalent control authority between the conventional wing and CC wing.

By observing facts of the “reversal of agglomeration” of Chinese enterprises during the period of rapid Internet development and using a new economic geography model combined with the data of the real estate sector, this paper deduces the influence of the “reshaping mechanisms” of the Internet on China's economic geography based on the “gravitation mechanism” of the Internet that affects the enterprises and the “amplification mechanism” of the Internet that amplifies the dispersion force of house prices.

In the empirical aspect, the dynamic spatial panel data model is used to test the micromechanisms of the impact of the Internet on enterprises' choice of location and the instrumental variable method is used to verify the macro effects of the Internet in reshaping economic geography.

It is found that in the era of the network economy, the Internet has become a source of regional competitive advantage and is extremely attractive to enterprises. The rapidly rising house price has greatly increased the congestion cost and has become the force behind the dispersion of enterprises. China's infrastructure miracle has closed the access gap which gives full play to network externalities and promotes the movement of enterprises from areas with high house prices to areas with low house prices.

The Internet is amplifying the dispersion force of congestion costs manifested as house prices and is reshaping China's economic geography. This paper further proposes policy suggestions such as taking the Internet economy as the new momentum of China's economic development and implementing the strategy of regional coordinated development.