The impulse wave is a universally existent hazard induced by landslides nearby water basins.Predicting the characteristics of the impulse waves is of great importance for risk assessment of landslide generated waves.Previous studies often focused on the instant wave pa-rameters and selected several landslides parameters such as thickness and velocity to build predictive models for wave characteristics such as height and amplitude.The time series relations between landslide parameters and wave parameters need to be determined.This paper gives insights into the time series variation of the wave characteristics.Experiments are first conducted by using granular particles,and a time se-ries panel database is built by using experimental data.Then a time series prediction model is established for wave characteristics based on a random coefficient panel data model,and the model is tested with the support of experimental data.The proposed model provides a temporal predictive method,which compensates for the deficiency of conventional models that can only predict the instantaneous wave parameters.
The water environment in rural areas is not only an important source of water for rural residents,but also closely related to agricul-tural production,sustainable development of rural economy,and farmers'health.How to improve the water environment in rural areas has become an urgent and important issue to be solved.This paper integrates exogenous incentives theory and organizational trust theory into a unified analysis framework,using 962 household survey data from provinces such as Jiangsu,Anhui,and Shaanxi.Using the Double-hurdle model,the impact of exogenous incentives and organizational trust on farmers'willingness to participate in water environment governance is empirically analyzed,and the mediating effect of organizational trust is explored to provide a reference for promoting good governance of vil-lage water environment.The research results indicate that firstly,exogenous incentives have a significant positive impact on farmers'willing-ness and degree of participation in water environment governance.From a multidimensional perspective,both economic and emotional incen-tives have a significant positive impact on farmers'willingness and degree of participation in water environment governance.Reputation in-centives only have a significant promoting effect on willingness to participate.Secondly,organizational trust has a significant positive impact on farmers'willingness to participate in water environment governance,but it does not have a significant impact on the level of participation.From a multidimensional perspective,goodwill trust has a significant positive impact on farmers'willingness and level of participation in wa-ter environment governance.And competence trust has only a significant promoting effect on willingness to participate.Thirdly,a further mechanism analysis has found that organizational trust plays a positive mediating effect between exogenous incentives and farmers'participa-tion in water environment governance decision-making behavior.Based on the above research conclusions,this paper suggests that:firstly,village committees should improve the exogenous incentives mechanism for farmers to participate in water environment governance.The first step is to establish a credit system and punishment system for rural water environment governance,and moderately increase the performance rewards for public welfare positions such as river guards and cleaners.Then,the village committee should regularly carry out"Healthy Fami-ly"evaluation activities,actively promote exemplary models of protecting the village environment,and guide village social public opinion by utilizing farmers'emphasis on personal reputation to enhance their sense of responsibility and honor and shame in protecting the water envi-ronment.Furthermore,the village committee should actively explore the unique customs and habits of the village,regularly organize collec-tive cultural and entertainment activities to enhance the cohesion between farmers,and strengthen the relationship between the cadres and the masses to enhance farmers'sense of belonging to the village.Secondly,grassroots autonomous organizations should strive to enhance their credibility.On the one hand,grassroots governments need to regularly carry out training activities on the professional abilities of village cadres,continuously improve their office skills,and establish a talent reserve system for village cadres to strengthen the organization's talent team.On the other hand,the village committee should improve the"four discussions and two disclosures"system,standardize the proce-dures for disclosing village affairs information,safeguard the rights of farmers to know,participate,and supervise,in order to establish a fair and just image of grassroots autonomous organizations.Thirdly,the village committee should enhance farmers'subjective awareness of pub-lic affairs participation.It not only needs to fully leverage the initiative of farmers through regular organization of courtyard meetings and the establishment of opinion boxes,but also avoids the formalization of grassroots election systems,in order to ensure the political participation rights of farmers and reduce their dependence on the government.
The multi-trough aqueduct is a new type of aqueduct structure,which has the advantages of large cross section water flow,good overall workability and small deflection deformation of the channel body,but the channel body is more sensitive to uneven vertical deforma-tion.In view of the fact that this type of structure is still the first in the water conservancy industry in our country,how to establish a multi-trough aqueduct operation safety early warning monitoring index is an important problem in project operation management.At present,do-mestic scholars have put forward a number of monitoring models about aqueducts,but these models do not give clear monitoring indicators,and do not reflect the modern monitoring concept of"hierarchical monitoring,step-by-step warning".Therefore,based on the previous re-search work,this paper proposes taking the non-uniform vertical deformation at the support as the main monitoring index,and the measured value of the reinforcement at the inner wall of the trough as the secondary monitoring index,and the research results can provide a reference for the safe operation of the multi-trough aqueduct.
By using the principle of bionics,this paper treats the front,middle and rear parts of the blade working surface with hemispherical non-smooth structure,combined with the flow field CFD and acoustic field LMS for simulation calculation.The flow field and sound field re-sults of the design flow of a centrifugal pump are compared and analyzed.The results show that the non-smooth structure makes the frictional resistance of the blade smaller,and then effectively reduces the shear stress and turbulent kinetic energy on the blade surface,and the weak-ening effect is most obvious at the blade entry and exit.At the same time,the vortex strength in the impeller flow channel is significantly re-duced,and the internal vortex distribution of the pump is more uniform,which can effectively reduce its turbulent pulsation intensity as a whole,stabilize the flow field and effectively reduce the flow noise.The non-smooth structure blade can effectively reduce the total sound pressure level,among which the optimal noise reduction at the impeller outlet is 3.28 dB and the noise reduction rate is 1.9%.The total sound pressure level at the diaphragm is reduced by 3.11 dB,and the noise reduction rate is 1.82%.In summary,non-smooth blades have a good noise reduction effect compared with smooth blades,and the overall noise reduction rate is about 0.81%～1.90%.
In order to explore the evolution of hydrological cycle in the agro-pastoral ecotone under changing environment,this paper takes Mu Us Sandy Land as the study area,and data of geological,hydrological,meteorological,and applies artificial water withdrawal to estab-lish a surface(Water and Energy transfer Processes in Large river basin,WEP-L)-groundwater(Visual Modular Finite Difference Ground-water Flow,Visual-MODFLOW)joint model,the model parameters are calibrated and verified by using the monthly surface runoff data of Baijiachuan hydrological station and groundwater table data.The results show that the NSE of the monthly runoff simulation of the WEP-L model calibration and verification period is above 0.40,the R2 is above 0.65,and the relative error is within±15%,the model is relatively accurate in simulating the monthly surface runoff process in the dry season at Baijiachuan Hydrological Station.Meanwhile,the R2 of ground-water table simulated and measured during the simulation period of four representative wells in the study area simulated by the Visual MOD-FLOW model is basically above 0.58,the MAE is less than 0.3m and the RMSE is between 0.028～0.265m,suggesting that the established surface water-groundwater model can be used for distributed simulation of hydrological cycle process in the Mu Us Sandy Land.On this ba-sis,the spatial distribution characteristics of surface water-groundwater in Mu Us Sandy Land are further explored.The results show that the surface runoff and groundwater table in different regions of the Mu Us Sandy Land are significantly different,and the groundwater table is low in places with large surface runoff.From 2019 to 2020,the runoff in the Mu Us Sandy Land decreased,but the spatial distribution was basi-cally the same,showing a gradual increase from the west to the east,and the runoff in the southeast corner of the area was the largest.The groundwater table in the area remained almost unchanged from 2019 to 2020,showing that the amount of groundwater recharge and extrac-tion are basically the same.In terms of space,the difference in groundwater table in the adjacent areas of the southeast and northeast corners of the sandy land is relatively large,and the water table drops faster,which is similar to the topographical change.The research results can provide scientific support for agricultural water allocation in the agro-pastoral ecotone,and for the regional water resources planning and management.
