Abstract: The paper summarizes the results of the performance of wave dissipation of an artificial sand bar experimental study under regular waves .In the experiment, the water levers are 0.00m、design high water level (1.35m) and extreme high water level (2.66m) ,it chooses the corresponding the limit wave height of three kinds of water level ,and analyzes the influences of relative height of artificial sand bar (d/H)、relative water depth of artificial sand bar (R/H) and wave steepness (H/L) on transmission coefficient of wave.The result shows that artificial sand bar has well the performance of consuming wave energy, the incident wave height starts up clearly decrease, while wave passes through artificial sand bar.With changing in conditions of artificial sand bar geometric dimensioning and wave parameter, transmission coefficient of regular waves also Changes.
Abstract: In view of the little sample, less data problems, mid-and-long term hydrologic forecasting is a case of which, Support Vector Machine (SVM) can solve this kind of problems perfectly. This paper introduced the basic optimization procedure and PSO-SVM modeling procedure. The PSO-SVM model has been applied in forecasting the monthly runoff of Dahuofang reservoir. The comparison between PSO-SVM and not-optimized SVM implied that the PSO-SVM has a fast convergence speed and strong generalization capability, also the related error has been decreased from 15.5% to 11.9%.
Abstract: Chen Clan academy square reconstruction project is one of the Asian Game projects. The depth of the foundation pit of the green square is about 12.1m. The difficulties of the excavation are the protection of the ancient buildings of Chen Clan academy and the surrounding buildings and the relatively short construction period. Thus, a top-down construction method was selected as the final method. For security, reliability analyses based on Taylor series technique have been performed to the factor of safety of whole stability, stability against overturning, stability against basal heave and stability against seepage. The results show that the design of the supporting structure is generally reliable, but there are also some potential safety hazards which should be noticed. The application of Taylor series technique also shows the simplification and practicality of this method.
Abstract: Based on the actual measurement datum in flood seasons in the Ningmeng Reach of the Upper Yellow River Reach, Authors search the law of erosion and deposition and sediment transport characteristics with built the quantitative correlation of erosion and deposition efficiency and water and sediment combination (sediment coming coefficient, sediment concentration/discharge)of the flood season. When the sediment coming coefficients of flood season is0.0038kg.s/m6 the Ningmeng reach in relative equilibrium state. The Ningmeng reach has the characteristic of “the more sediment coming, the more depositing, the more sediment transporting”, the sediment discharge increases with sediment concentration of coming flow increasing. The result of these research can be used in the Yellow River management and alluvial channel regulation.
Abstract: The hydro-dynamic environment will be changed after reclamation project building. It will affect the navigation, estuary regime, tidal prism, flood controlling, storm surge and so on. Taking the shore reclamation between Oujiang and Feiyunjiang estuary as example, a tidal current mathematical model is used to study the effects of the large-scale reclamation on the hydro-dynamic environment. Based on triangle grid and finite volume method, the shallow flow model is examined by 9 tidal level stations and 9 observed synchronous vertical lines. And the comparison between computed result and measured solution demonstrates very good agreement. After the project building, the high tide level reduces to a certain extent and the flow of front reclamation line reduces by a big margin. But it is a little influence to the core ports of Wenzhou. And the tidal influx through Feiyunjiang Estuary decreases. The result can provide important reference and inspiration for the effects of hydro-dynamic environment due to the large-scale reclamation projects.
Abstract: Tunaozi reach is one of the three famous sediment depositing reach on the Sichuan section of Yangtze River. It’s on the fluctuation backwater area when the Three Gorges Project is operated at the level of 135 m. According to the measured data before and after impoundment, this paper analyzes and calculates the sediment of the reach, and discusses the variation of silting and scouring of the reach after impoundment. Thus, this paper will have a study on the reason that silting and scouring lead to channel condition change. The result as follow: after impoundment, the bank-up water level of the reach has been head up 2 m during the flood season, sediment deposition becomes heavier than before impoundment; in post-flood season, the water level is 139m in November, it has been head up 7 m, compared with low water level in natural, current slowly flow further, the silt lack of enough scour in flood season, it leads to cumulative deposition. Until December 2005, thalweg plane position move left 200 m after impoundment. The maximum silting height of the thalweg longitudinal section is 30 m. The prime channel has been basically silted flat, year. Since the Three Gorges reservoir began to store water for three years, in low water level periods, ship tank is out of shallow, some timely dredging measure should be taken and make sure the smooth channel.
Abstract: This paper has discussed the working principle and characteristics of the new commonly used pipeline repair technology by introducing the currently commonly used pipeline repair technology. The new commonly used pipeline repair technology can be classified as two big kinds including one based on excavation and trenchless technology. When selecting the pipeline repair technology, we mainly considerate four factors: whether excavat pipeline , whether cut off the water and the time of cutting off water , the time of pipeline repair , the materials of pipeline repair, and so on . The actual situation and network features of water supply network in Fangcun district of Guangzhou are analysed , the joint repair technology strategies of water supply network which applies to Fangcun district are discussed by synthesizing the applicability, merit and demerit of new pipeline repair technology, and use these as technical reference and guidance for other similar areas .
Abstract: At the present time, the accident remains at a high level all over the world. It mostly happened on the two-lane mountain highway. Through analysis of the relationship between radius of horizontal curve and driving safety of the drivers on two-lane mountain highway, variations of heart rate was be introduced. The variations of heart rate will be changed with Radius of horizontal curve through qualitatively and quantitatively analysis. However, the maximum of drivers' heart rate does not occur on the limit radius of horizontal curve. It locates at the place slightly larger than the limit radius of horizontal curve. The model between heart rate variation and radius of horizontal curve square was established. Finally, some useful advises were suggested to strengthen the two-lane highway management.
Abstract: Present sustainable development is one of the hot topics in the world, and the traffic transportation system is regarded as a subsystem of the social economic system. There is important strategic position in the development of national economy. There are important realistic meanings to study the sustainable development of the transportation system. This paper focused on the analyzing the major traffic problem in sustainable development of the transportation, proposed the intellectual transportation system (ITS) is the key to achieving development of the transportation in China, and discussing how to make use of transportation system of intelligence to achieving sustainable development strategy of the traffic system, some suggestions on developing program and the application of the system architecture in future are presented.
Abstract: Differential Transform Method (DTM) is a new semi-analytical, semi-numerical algorithm, which transforms differential equations to the form of Taylor series. The method derives an approximate numerical solution based on Taylor series expansion, which is an analytical solution built on polynomial form. Traditional Taylor series method is used for symbolic computation, while Differential Transform Method obtained the solution of the polynomials through itineration calculations. Applying DTM to buckling problems, the critical length of a bar at clamped-clamped boundary is studied. The computational results are compared with analytical solutions and shown excellent agreement between those two algorithms. The method adds a new tool to the fields of computational engineering mechanics. Differential Transform Method is much easier, and more efficient when compared with other computational methods.