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Research Interests:
Research Interests:
Research Interests:
Research Interests:
Flow resistance, velocity distribution, and turbulence intensity are significantly influenced by aquatic vegetations (AV) in riparian zones. Understanding the hydraulics of flow with planted floodplains is of great significance for... more
Flow resistance, velocity distribution, and turbulence intensity are significantly influenced by aquatic vegetations (AV) in riparian zones. Understanding the hydraulics of flow with planted floodplains is of great significance for determining the velocity distribution profile and supporting the fluvial processes management. However, the traditional flume experiment method is inefficient. Therefore, the multigroup simultaneous flume test method was carried out to describe the flow patterns affected by emerged rigid (reed and wooden stick) and submerged flexible vegetations (grass and chlorella). The Acoustic Doppler Velocimeter (ADV) was utilized to measure the velocity at one point for different experimental conditions. The results showed that hydraulic features were influenced by different types of vegetation. Furthermore, the relative depth (z/h) was a determining factor of those variations. In addition, the time-averaged velocity distributions of planted floodplains are not loga...
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Objective To investigate clinical efficacy and safety of endoscopic multiband mucosectomy(EMBM) for esophageal submucosal tumors(SMTs). Methods Data of 51 patients with SMTs diagnosed between Jan 2012 and Aug 2014 were retrospectively... more
Objective To investigate clinical efficacy and safety of endoscopic multiband mucosectomy(EMBM) for esophageal submucosal tumors(SMTs). Methods Data of 51 patients with SMTs diagnosed between Jan 2012 and Aug 2014 were retrospectively studied. Of the 51 patients, 33 patients(34 lesions) received EMBM and 18 patients received endoscopic submucosal resection(ESMR). The operation success rates, complete resection rates, procedure time, complications and the follow-up of group EMBM and group ESMR were compared. Results All of 51 cases had successful endoscopic treatment with no perforation, infection or obvious bleeding. Follow-up showed no recurrence after operation. Compared with group ESMR, group EMBM had higher complete resection rate[97.1%(33/34) VS 61.1%(11/18), P=0.010], shorter operation time[(6.3±1.8)min VS (21.4±3.8)min, P=0.001] and lower complication rate[6.1%(2/33) VS 27.8%(5/18), P=0.024]. Conclusion EMBM is simple, safe and effective for treating SMTs originating from mus...
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Objective To evaluate the efficacy and safety of the unilateral and bilateral drainage in hilar malignant biliary obstruction with a meta-analysis of relevant studies. Methods A systematic electronic search with keywords "biliary... more
Objective To evaluate the efficacy and safety of the unilateral and bilateral drainage in hilar malignant biliary obstruction with a meta-analysis of relevant studies. Methods A systematic electronic search with keywords "biliary stent", "hilar tumor" and "malignant biliary obstruction" was independently performed by two reviewers in major electronic databases of Pubmed, EMBASE, Cochrane Library and Web of Science. A meta-analysis was conducted using Revman 5.1 software. Results Six studies were included with a total number of 558 patients, of whom 307 patients underwent unilateral biliary drainage and 251 patients bilateral drainage. There was no significant difference in early complications (OR=1.03, 95%CI: 0.58-1.81, P=0.93), later complications (OR=0.98, 95%CI: 0.46-2.07, P=0.95), operation success rate (OR=1.42, 95%CI: 0.76-2.66, P=0.28), drainage efficacy or median survival time between the two groups. Compared with unilateral biliary drainage, bi...
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Water energy is a conventional source of source that is widely available in nature. It can be easily converted into high quality secondary energy-electric energy through hydroelectric power stations. Hydropower is not only a widely used... more
Water energy is a conventional source of source that is widely available in nature. It can be easily converted into high quality secondary energy-electric energy through hydroelectric power stations. Hydropower is not only a widely used conventional energy source, but also a renewable energy source. Moreover, hydroelectric power has no pollution to the environment. Therefore, water energy is an inexhaustible and high-quality energy source among many energy sources in the world. However, vegetation can change flow structure and turbulence characteristics, impacting the use of water energy. In previous researches, few studies have focused on the comparison of velocity and turbulence influenced by various vegetations. Therefore, laboratory experiments were carried out to investigate hydrodynamics affected by submerged rigid vegetation (reed and wooden stick) and merged flexible vegetation (grass and chlorella) under different conditions. The time-averaged velocity distributions of plan...
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The seismic response of underground structures in nonlinear foundations was analyzed by using FLAC 3D software, and the effect of relative wavelength on the transverse strain transfer rate of structures is studied. The variation processes... more
The seismic response of underground structures in nonlinear foundations was analyzed by using FLAC 3D software, and the effect of relative wavelength on the transverse strain transfer rate of structures is studied. The variation processes of the strain transfer rate can be divided into three distinct phases. In the first stage where the relative wavelength raises from 0.2 to 1.0, the strain transfer rate increases almost linearly with it; while in the second stage where the relative wavelength increases from1.0 to 2.0, the growth trend is slowing down. And the strain transfer rate almost keeps a constant value during the last phase, in which stage the uniform strain field of soil can be used to analyze the strain transfer rate. According to the influence of relative wavelength and relative stiffness on the strain transfer rate, the calculation formula of the strain transfer rate is summarized.
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The elastic properties such as shear moduli and shear moduli of freezing and thawing soil are important parameters for analyzing the stress distribution and thaw-subsidence of freezing soil and deformation of well casing embedded in... more
The elastic properties such as shear moduli and shear moduli of freezing and thawing soil are important parameters for analyzing the stress distribution and thaw-subsidence of freezing soil and deformation of well casing embedded in freezing soil. This paper presents elastic properties obtained by conducting laboratory testing of sand samples from the area of soil. The bending elements were used to measure the shear wave (S-wave) velocities for evaluating the shear moduli during freezing and thawing. Nine pairs of testing specimens were conditioned from 25°C to -25 °C at an interval of 5 °C for examining the temperature effects during freezing and thawing process, respectively. The test parameters included dry density (1.6,1.8,2.0 g/cm3) and moisture content(6%,9%,the saturation). Test results showed that the wave velocities and the shear moduli in all types of specimens tested exhibit sharp change when the temperature adjacent to 0 °C, likely due to non-uniform freezing point depre...
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An experiment study was conducted to assess the effectiveness of acoustic emission (AE) technique monitoring the corrosion-induced damage in the marine environment. Three reinforced concrete (RC) piles of 1600 mm long by 200 mm square... more
An experiment study was conducted to assess the effectiveness of acoustic emission (AE) technique monitoring the corrosion-induced damage in the marine environment. Three reinforced concrete (RC) piles of 1600 mm long by 200 mm square were casted and then were exposed in a simulated marine environment to reach 5%, 10% and 20% of steel rebar mass loss respectively. Throughout the whole test period, all specimen was monitored by three AE sensors installed at two different heights of the concrete surface and at the end of the steel rebar, respectively. The AE activities were analyzed to determine corrosion-induced dterioration at different corrosion levels. Based on the finding, the effectiveness of AE technique on monitoring of RC piles of high-pile under aggressive marine environmental conditions was established.
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This paper presents an experimental study of reinforced concrete beams strengthened with CFRP laminates and anchored with carbon fibre anchors under monotonic static and cyclic loading. To gain full advantage of externally bonded CFRP... more
This paper presents an experimental study of reinforced concrete beams strengthened with CFRP laminates and anchored with carbon fibre anchors under monotonic static and cyclic loading. To gain full advantage of externally bonded CFRP technique, it is important to avoid premature debonding of the laminates, and CFRP anchors have the potential to prevent this happening by transferring the stress from steel reinforcement to the laminates. In this study, cyclic tests were conducted to investigate the fatigue behaviour of the strengthened beams and to identify strengthening effects of various anchoring depths. The aim of the monotonic tests was to determine strengthening efficiency of the new anchoring technique and to evaluate serviceability and ultimate states of the beams. According to the results, a damage index was proposed based on fractal analysis of cracks under cyclic loading and validated through ultrasonic inspection analysis. In addition, an empirical equation between averag...
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The salt which origins from offshore zone is easy to gather in the semi-closed space formed by beams and slabs of pile-supported wharf called gridiron space, and that could induce the premature failure of durability of the wharf’s... more
The salt which origins from offshore zone is easy to gather in the semi-closed space formed by beams and slabs of pile-supported wharf called gridiron space, and that could induce the premature failure of durability of the wharf’s substructure. Previous work commonly focused on material-level measures which will lead to increased costs such as anti-corrosion concrete and anti-corrosion coatings to eliminate the adverse effects of that gathering of salt fog. In fact, the salt fog could be extracted from the gridiron by natural ventilation in some cases, so it is necessary to examine the flow characteristics in the gridiron space. In this work, the numerical simulation has been conducted with natural ventilation and auxiliary ventilation group. Critical value of the blocking ratio (defined as height ratio of edge stringer to air inlet) that makes the airflow inside the gridiron reach the strongest turbulence is found in natural ventilation group. In addition, the effect of different a...