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With the extensive use of structural health monitoring technologies, vibration-based structural damage detection becomes a crucial task in both academic and industrial communities. Following the noteworthy trends of data-driven paradigms in recent years, some solutions have been released to identify, localize, and classify damages via deep neural networks. However, some deficiencies still exist for effective damage-intensive feature extraction and representation. To overcome such a problem, this paper proposes a novel end-to-end structural damage detection neural model by taking the advantages of the Convolutional Neural Network and Bidirectional Gated Recurrent Unit in parallel. The well-known IASC-ASCE benchmark and TCRF dataset are used for evaluation. The experimental results show that the proposed approach can achieve a better detecting effect than other existing manners.

A 2D depth-averaged model for hydrodynamic sediment transport and river morphological adjustment was established. The sediment transport submodel takes into account the influence of non-uniform sediment with bed surface armoring and considers the impact of secondary flow in the direction of bed-load transport and transverse slope of the river bed. The bank erosion submodel incorporates a simple simulation method for updating bank geometry during either degradational or aggradational bed evolution. Comparison of the results obtained by the extended model with experimental and field data, and numerical predictions validate that the proposed model can simulate grain sorting in river bends and duplicate the characteristics of meandering river and its development. The results illustrate that by using its control factors, the improved numerical model can be applied to simulate channel evolution under different scenarios and improve understanding of patterning processes.

The amount of fine sediment deposition in some river reaches in the permanent backwater zone of the Three Gorges Reservoir has exceeded predictions made during the design period of the reservoir. In this study, a series of laboratory experiments were conducted on field samples of fine sediment from the Zhongxian reach, a typical reach in the permanent backwater region of the Three Gorges Reservoir. Compared with the existing formulas, an improved incipient velocity function for fine-grained sediment deposits was developed that includes the influence of water pressure and molecular force. Here we present a 2-dimensional (2D), depth-averaged, hydrodynamic-morphological model for simulating channel evolution processes. The proposed velocity formula was considered in the calculation of sediment transport, and the improved 2D numerical model was applied to the sedimentation process of the Zhongxian reach. Comparisons between model simulation results and field measurements were in acceptable agreement, ...

Slowing down or even stopping light is the first task to realising optical information transmission and storage. Theoretical studies have revealed that metamaterials can slow down or even stop light; however, the difficulty of preparing metamaterials that operate in visible light hinders progress in the research of slowing or stopping light. Metasurfaces provide a new opportunity to make progress in such research. In this paper, we propose a dendritic cell cluster metasurface consisting of dendritic structures. The simulation results show that dendritic structure can realise abnormal reflection and refraction effects. Single- and double-layer dendritic metasurfaces that respond in visible light were prepared by electrochemical deposition. Abnormal Goos-Hänchen (GH) shifts were experimentally obtained. The rainbow trapping effect was observed in a waveguide constructed using the dendritic metasurface sample. The incident white light was separated into seven colours ranging from blue to red light. The measured transmission energy in the waveguide showed that the energy escaping from the waveguide was zero at the resonant frequency of the sample under a certain amount of incident light. The proposed metasurface has a simple preparation process, functions in visible light, and can be readily extended to the infrared band and communication wavelengths.

Devitrification which occurred in the ground coat (fired at 830°C for 0–30 min) due to interdiffusion near the steel-enamel interface was characterized by electron microscopy (SEM and TEM) coupled with energy-dispersive X-ray analysis. Spinel oxide, Fe3O4, which was alloyed with Ni if nickel-dip pre-treatment was adopted and was compatible with α-Fe, crystallized in the ground coat near the glass-metal interface. Independent of nickel-dip pre-treatment the spinel crystals were extensively developed at the edges of the specimen slab, but were fewer and smaller in the centre of the flat faces. The quantity and size of crystals increased with the firing time. Within the titania-opacified cover coat (fired subsequently at 800°C for 3 min) equiaxed TiO2 crystals (anatase with a minor amount of rutile) were distributed uniformly. The TiO2 crystals grew inwards to some extent into the ground coat and became needle-like with their long axes aligned diagonally to the interface. The devitrification of enamel was affected significantly by diffusion across the interfaces which resulted in a saturation with oxide components.

We compare several approaches and their tradeoffs to achieving terabit/s transmission in SMF with 40 km and/or 80 km repeater spacing. Capacity and maximum transmission distances in multiple low-loss windows are discussed.

Biliary stricture represents a challenging problem in the treatment of hepatolithiasis because of its association with treatment failure and stone recurrence. The long-segment type of stricture is difficult to manage and is likely to recur. To investigate the necessity for biliary stenting after balloon dilatation therapy, 20 consecutive patients with long-segment strictures who had 22 stents (group 1) were compared with ten patients who refused stenting (group 2). The long-segment strictures in group 1 were located on the right side in 80 per cent of patients, on the left side in 10 per cent, and were bilateral in 10 per cent. The stents, varying from 8 to 12 Fr, were retained for at least 6 months. They were inserted through the routes of a matured T tube track (five cases), percutaneous transhepatic track (14 cases), a jejunal limb (two cases) and a fistula (one case). Complications of stenting consisted of dislodgement (one case), haemobilia (two cases), cholangitis (two cases) and intrahepatic abscess (one case). The cumulative probability of stricture recurrence in group 1 was 10 per cent, 15 per cent and 21 per cent at 2, 3 and 4 years, respectively, whereas in group 2 it was 80 per cent at 2 years (P < 0.003). The results suggest that intrahepatic biliary stenting after balloon dilatation appears necessary and helpful in the management of hepatolithiasis with long-segment biliary strictures.

Among all dramatic and operatic forms in China, Peking Opera is perhaps the most popular one, and has been enjoyed by the people for more than a hundred years. The name “Peking,” however, does not really suggest the origin of this opera. Its Chinese name is p'i-huang, or erh-huang, which does indicate the origin of the opera. The word “p'i” in Chinese means “tunes,” and the character “huang” refers to one or two districts located in Hupeh province (the other name “erh-huang” means “two Huangs”) where this kind of music first originated, although the district of Huang-kang is generally believed to be the birthplace of this opera. Apparently this new kind of music soon spread to other districts of Hupeh, as well as to the adjacent provinces including Anhwei. The popularity of this new opera form encouraged and justified professional organisations, and troupes brought the opera to Peking, then the capital city of the Manchu (Ch'ing) dynasty. However, credit went to the Four Great Anhwei Troupes for their role in establishing this opera in the capital during the waning years of the Ch'ing period. The patronage of official circles, especially the royal clans in the Manchu court, helped tremendously in gaining fame and position for this new opera form. The Empress Dowager, Tz'u-hsi, so enjoyed this opera form that she ordered private theatres built in the palaces for her own enjoyment. (One of such theatres is still standing in the Summer Palace today.) As a result, the new operatic form was given a new name, ching-hsi (“Capital Opera”). And since Peking was the capital then, it was nicknamed the “Peking Opera” which subsequently has become the recognised name for it.

In the opinion of the Communists, the significance of the Literary Renaissance in modern China beginning with the May Fourth movement of 1919, lies not in that it introduced the colloquial language as the new medium for literature, but in that it ushered into China a new literature which replaced the “old-fashioned, out-of-date literature of the bourgeois class.” But the new literature which the Communists had hoped for did not fully develop until the political revolution led by the Communists succeeded, and a new régime was established in 1949. To implement the literary revolution and to introduce the people's new literature, the Communist régime called the first conference of the All-China Federation of Literary and Art Circles in July, 1949 at which the government spokesmen expounded the concepts and scope of this new literature and outlined a programme for “literary workers” to follow. Since these expositions were indeed the expressions of the policies of the new régime on literary reform and are therefore pertinent to the discussion in this paper, they must be cited here as a point of reference.