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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.

As an extremely important part of traffic arteries, bridge structure plays an essential role in national economic construction, social development and smart city. Thus the monitoring of the bridge structure health are increasingly concerned by the bridge industry scholars and engineering people at home and aboard. In this paper, we propose a deep learning framework to evaluate the safety of the bridge structural state. More specifically, the proposed system generates a learnable transformation which attempts to map most of the data network representations into a hypersphere characterized of minimum volume. During inference, mappings of normal examples fall within the learned hypersphere, whereas mappings of anomalies fall outside the hypersphere. The whole system is end-to-end trainable and outperforms other advanced methods in real-world dataset.

In this study, the dynamic behavior of bed-load sediments under unsteady flow conditions is experimentally investigated and discussed. A series of experiments were conducted in a 6-m-long ...

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, ...

A 1-dimensional (1-D) numerical model was developed to simulate the formation and distribution of fine sediment deposition in the Three Gorges Reservoir. Based on the research of fluid mud in estuaries, a dynamic submodel of gravity-driven, fine sediment transport was developed using the staggered grids and finite volume method and a 2-order Runge-Kutta time processing format. This submodel was first verified for fine sediment deposition in a typical section of Three Gorges Reservoir and was then combined with a 1-D hydrosediment transport submodel to reproduce sedimentation in the dam area of the Three Gorges Reservoir. Results for selected variables indicated that the distribution of sedimentation is in acceptable agreement with field observations and demonstrate the ability of the 1-D model to improve understanding of the fine sediment deposition in the Three Gorges Reservoir.

In this study, the modified preparation method of combining planetary and vibratory ball milling was proposed to prepare Mg based hydrogen storage alloy powders. The comparison of micromorphology and hydrogen storage behaviour between Mg2Ni prepared using the modified and conventional preparation methods were investigated experimentally. The comparison results showed that the combination of first planetary and then vibratory ball milling has more favourable effect on improving both the kinetics and the thermodynamics of ball milled Mg2Ni alloys. The sample synthesised by first planetary milling for 40 h and then vibratory milling for 30 h has faster hydrogen absorption kinetics and lower dehydriding onset temperature than those prepared by the single method of planetary or vibratory milling and hydriding combustion synthesis owing to its popcorn-like microstructure. Moreover, this kind of modified method reduces the reaction enthalpy and activation energy by up to ∼18 and 22% respectively.

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.

The coherence properties of InAs quantum dot emissions in quasi-L2 photonic crystal nanocavities were studied using g ( 1 ) ( τ ) first-order correlation measurements at room temperature. A soft turn-on of the coherent state at ultra-low threshold power indicated that the quantum dot emissions in the cavities had exhibited a smooth transition from spontaneous to stimulated emission.

Osteoporotic patient has low bone quality and often occur unstable fracture. Conventional dynamic hip screw method can provide good result on stable femoral fracture. On the unstable femoral fracture, it has high failure rate. The purpose is to investigate the biomechanics analysis for dynamic hip Screw on osteoporotic and unstable proximal femoral fracture. The specific aims are to :(1) develop the osteoporotic and unstable proximal femoral fractures model,(2) investigate the influence of lesser trochanter fixation on stress and deformation distribution.

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.

Background: Contrast-medium extravasation injuries may be self-limited to catastrophic. Adequate prophylactic measures are enforced when risk factors for extravasation are present, and prompt treatment can avoid serious complications. Purpose: To describe the squeeze maneuver, an effective method for the treatment of symptomatic contrast-medium extravasation. Material and Methods: Over a 3-month period, eight patients with >50 ml contrast-medium extravasation resulting in vascular compromise of the fingers were managed with the squeeze maneuver as follows. The intravenous catheter used for contrast-medium injection was removed, and the skin around the insertion site was cleaned with povidone-iodine. An 18-gauge needle was then used to puncture five to eight openings near the catheter insertion site as deeply as possible. We then began squeezing from the periphery of the swelling toward the needle holes. As the contrast medium drained, it was swabbed away with iodine-soaked cotton swabs. Results: In all eight patients, the maneuver was successful with immediate resolution of the vascular compromise. Conclusion: The squeeze maneuver provides an easy way to manage radiological contrast-medium extravasation and can be performed immediately in the CT suite.

Conventional percutaneous procedures for treating patients with recurrent hepatolithiasis associated with complicated intrahepatic biliary strictures require multiple dilation sessions before stone extraction. We modified the approach, reducing the number of dilation sessions required and using newer lithotripsy and irrigation methods. We suggest that the modified procedures are superior to conventional management and demonstrate their utility in clearing hepatolithiasis.Percutaneous transhepatic stricture dilation and cholangioscopic lithotripsy were performed to treat patients with right recurrent hepatolithiasis with complicated intrahepatic biliary strictures. Conventional methods were used in 40 patients (Group A). Modified methods, including simplification of tract establishment and stricture dilation and electrohydraulic lithotripsy (EHL) were used in 60 patients (Group B).Group B patients had fewer complications (massive hemobilia: 0% versus 15%, P = 0.0032, cholangitis: 0% versus 17.5%, P=0.0012), tolerated the procedures better (intolerable pain: 0% versus 12.5%, P=0.0087), had a higher rate of success (residual stones: 3.3% versus 20%, P=0.0132; remaining asymptomatic and stone-free: 81% versus 50%, P = 0.0021), a shorter hospital stay (17.8 +/- 4.4 days versus 36.2 +/- 5.5 days, P0.001) and lower overall expense (USD 2689 versus USD 3848) than Group A patients.We believe that the modified methods are superior to conventional treatment in that they effectively decrease procedural complications and cost, and significantly improve treatment results.

Percutaneous stricture dilatation and cholangioscopic lithotomy has become a mainstay in the treatment of patients with recurrent hepatolithiasis associated with intrahepatic biliary strictures. In a consecutive series of 125 patients who underwent percutaneous management of recurrent hepatolithiasis from 1987 to 1999, there were 15 patients in whom the procedure failed to clear the stones. A second percutaneous transhepatic route was established for subsequent treatment. A reappraisal of its indications and efficacy was done. Treatment through a second route was helpful for patients with bilateral strictures, angulated duct, difficult strictures, large impacted stones, a subcutaneous jejunal limb, or hemobilia developing in the first route. Strictures remained impacted in 1 of the 15 patients (failure rate, 7%), with the remaining having complete clearance of stones. Cholangitis occurred in two patients; no other complications were encountered. A second percutaneous route is very helpful for the management of complicated hepatolithiasis and biliary stricture.

For recurrent hepatolithiasis coexisting with a complicated long-segment intrahepatic biliary stricture, repeated surgeries, balloon dilation of the stricture, and external-internal stenting may still fail to solve the problem. We tried using a Gianturco-Rosch metallic Z internal stent (Wilson-Cook Medical, Inc., Bloomington, IN, USA) with the aid of percutaneous transhepatic cholangioscopy (PTCS) to treat such patients. Eight patients had a Z stent placed through a percutaneous transhepatic biliary drainage tract. Immediately after stent placement, PTCS was inserted via the percutaneous transhepatic biliary drainage route and a part of the wire skirt not firmly anchored in one of the eight patients was detected. It was successfully repositioned using PTCS. Recurrent cholangitis developed in three patients 6, 7, and 30 months, respectively, after stent placement. PTCS was undertaken again through a reestablished percutaneous transhepatic biliary drainage route and revealed sludge in their stent lumens. We cleared it by PTCS. No further cases of cholangitis occurred in later follow-up. PTCS is useful in ensuring adequate stent position, diagnosing and treating the causes of recurrent cholangitis, and prolonging the function of stents.

To determine the alterations of the p16/MTS1 gene in oral squamous cell carcinoma (OSCC), we examined in Taiwanese patients the mutation, deletion and methylation of p16/MTS1 in primary OSCCs associated mostly with betel quid (BQ)/tobacco use. Among 110 tumors undergoing mutational analyses, seven (6%) showed mutations in exon 2 or the intron 1/exon 2 splice site. All but one mutation disrupted the encoded proteins. Base transitions represented the vast majority (6/7) of the mutations identified in BQ/tobacco consuming subjects. It was noted that 15/56 (27%) tumors examined by restriction fragment methylation analysis revealed a significant level of methylation in different loci of exon 1 as compared with the respective non-cancerous tissue. Mutation of p16/MTS1 was exclusively identified in carcinomas of buccal mucosa, whereas methylation of the p16/MTS1 promoter region occurred preferentially in carcinomas of the tongue (54%) rather than at other sites (22%). Homozygous deletion was not found in 56 paired samples examined, nor was hemizygous deletion indicated in 12 informative cases. The results indicated aberrant methylation and mutation as the molecular abnormality of p16/MTS1 in the OSCC from Taiwanese.

A fast recursive-least-squares (FRLS) adaptive notch filter (ANF) for cancellation of sinusoidal interference from recorded biomedical signals is investigated. The FRLS ANF is derived by making an approximation to the conventional recursive-least-squares (RLS) ANF for computation economy. It outperforms the commonly adopted least-mean-squares (LMS) ANF, demonstrating a rapid and bandwidth-insensitive initial convergence. A novel application of the FRLS ANF is for the elimination of the tonal artefact in distortion product otoacoustic emission (DPOAE) signals.

In case of hepatocellular carcinoma (HCC), the gallbladder is less frequently involved and metastasis to the gallbladder, together with its significant clinical manifestations, is rarely discussed in the literature in detail. HCC with metastasis to the gallbladder, initially presenting as gallbladder intraluminal hemorrhage and perforation, has not been previously reported. We present a case of HCC disclosed by emergency cholecystectomy for hemocholecyst with perforation. Evaluation of the possible metastatic mechanisms is also discussed.

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.

A case of watershed infarction in the spinal cord is reported. The patient underwent bronchial artery embolization for control of massive hemoptysis. The bronchial arteriogram was carefully examined and focused on blood supply to the spinal cord prior to embolization. Acute paraparesis followed the embolization procedure even though there was no visible spinal supply on the arteriogram. Magnetic resonance imaging showed a hyperintensity lesion over the watershed region which is located at the central portion of the upper thoracic cord. This case is reported to emphasize the significant role which angiographically invisible small vessels can play in the blood supply to the spinal cord. The vascular system of the spinal cord and the prevention of spinal cord ischemia secondary to embolization are further discussed here.

Recently we have shown theoretically that two-pump fiber optical parametric amplifiers (OPA’s) can exhibit highly uniform broadband gain spectra [1]: for example one can obtain 20 dB of gain over a 45 nm bandwidth, with uniformity of 0.2 dB. These calculations, however, did not include the effect of stimulated Raman scattering (SRS). Here we study the influence of SRS on the uniformity of the OPA gain spectrum, by starting from four-wave mixing (FWM) equations including SRS gain contributions. We show that in general SRS modifies the OPA gain spectrum, but that under realistic conditions the uniformity can remain quite good.

We have recently shown theoretically that a two-pump fiber optical parametric amplifier (OPA), operated near the fiber zero-dispersion wavelength, λ0, can exhibit very uniform gain over a wide wavelength range [1]. For example, a standard dispersion-shifted fiber operated near λ0 = 1550 nm can exhibit 20 dB of gain over a 45 nm bandwidth, with a gain ripple not exceeding 0.1 dB. The fact that the predicted ripple is so small raises the question of whether it might not be substantially increased by incorporating into the model some features left out of the original model as a first approximation. Of particular concern are the facts that we assumed: (i) a single nonlinearity coefficient γ to describe interactions between different waves; (ii) that this γ did not change with frequency. Even if (i) were correct, (ii) clearly is questionable because: 1) we are interested in large frequency ranges (say up to 50 nm bandwidth); 2) γ has both explicit and implicit wavelength dependences. Specifically, γ is given by γ = 2πn2/λA eff , where n2 is the nonlinear-index coefficient, λ is the vacuum wavelength, and A eff is the effective core area. Ae ff generally increases with λ, and thus the denominator of γ can exhibit a fairly strong λ-dependence. In addition n2, which is determined by the materials making up the core and cladding, may also be wavelength dependent. In this paper we study the influence of the dispersion of λAe ff on the OPA gain characteristics. We also assume a priori that the various interactions are governed by different γ’s, and we keep these throughout the entire calculation. We will show that, because of symmetries governing the interacting frequencies, the gain spectrum uniformity of the fiber OPA will not be greatly affected by the inclusion of these additional effects.

In order to be useful in a wide range of communication applications, fiber optical parametric amplifiers (OPA’s) and wavelength converters should operate on a cw basis. Furthermore, conversion efficiency Gi should be greater than or equal to one, in order to avoid the substantial signal-to-noise ratio degradation which occurs if Gi ≪ 1. Currently silica-based fibers have the best characteristics for making fiber OPA’s. However, owing to the relative weakness of the third-order nonlinear susceptibility in such fibers, amplification by fiber OPA’s requires a high pump power and/or a large fiber length. Pulsed amplification has been reported by a number of groups. CW fiber parametric amplification with a 17 dBm pump has been reported, but with a gain insufficient to overcome fiber loss [1].

A boy with tetralogy of Fallot diagnosed in infancy, presented for definitive correction at the age of 5 years and 3 months. He had undergone bilateral Blalock-Taussig shunts twice at 1 and 2 years of age, respectively. Cardiac catheterization and angiography prior to total correction revealed a major aorto-pulmonary collateral artery arising from the thoracic aorta and supplying the right upper lung. Embolization of the collateral artery with two platinum coils (via catheterization) was performed. The successful embolization exempted the patient from the risky ligation of the deeply located collateral artery.

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.

The distribution of succinic dehydrogenase (SDH) activity and the changes of SDH activity after injection of gentamicin (GM) were observed in the organ of Corti using non-decalcified frozen sections of the guinea pig's cochlea. The distribution of SDH activity was found to increase from the apex to the basal turn. At each turn, SDH activity of the inner hair cells, the inner supporting cells and the nerve endings surrounding the supporting cell and on the hair cells presented a greater activity than that found in the outer hair cells, adjacent Deiter's cells and associated nerve endings. It was further observed that GM had a greater effect on SDH activity in the basal turn than the other turns. At each turn, a more sensitive area of response to GM was found on the nerve endings one each hair cell, especially on the outer hair cells of the basal turn.

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.