Temporal and Spatial Characteristics of Tidal Current in the Eastern Waters of Macao in Summer by FANG Shenguang, HUANG Chunhua, YU Fenghua, WANG Shijun, HE Yong

“…The eastern waters of Macao at the Pearl River Estuary are an important channel for water and sediment discharged by the west beach of Lingdingyang Estuary and Macao waterway.The measured data during the flood seasons shows that the waters feature semi-diurnal tidal currents,and the average velocity in this area is about 21~23 cm/s during the flood and 18~29 cm/s during the ebb.The flowing direction is stable,namely,N—NNW trending during the flood and S trending during the ebb,and tidal power is stronger in the south.The average velocity in the waters is mainly dependent on the tidal type,and the flood runoff mainly affects residual currents and tidal duration.A stagnant area is formed in the north of the waters during the flood,and the water and sediment in the south are transported outside the Lingdingyang Estuary.Wind on the sea surface has a significant impact on the vertical dynamic structure of flow in the range of 40% water depth,and residual flow direction in the range of 10% water depth near the sea surface has a good follow-up.During southwest wind,the maximum horizontal flow velocity gradient appears in the second flood and ebb stage and corresponds to the occurrence of the maximum sediment concentration in the tidal cycle.Due to the shallow water depth in the north of the waters,the bed shear gradient force is generally greater than that in the south.As a result,the sediment concentration observed in the north of the waters is significantly higher than that in the southeast.According to the comprehensive analysis,astronomical tides,flood runoff,and wind are the main controlling dynamic factors in the waters.The friction resistance of shallow water in the north is drastically larger than that in the south,which leads to a significant difference in tidal duration and phases of vertical floods and ebbs.As a consequence,the special vertical dynamic structure of convergence on the surface and dispersion at the bottom is formed in the waters,which is strengthened by massive freshwater runoffs during the flood seasons.This leads to the trend of surface diluted water drifting to the east and the invasion of the nearshore by bottom high-salt water.…”
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Life cycle assessment and mechanical strength of cement composites with conventional, and recycled fine aggregate by Sk. Rakibul Islam, Sanjima Nabila Majumder, Rupak Mutsuddy

“…Unbridled sand extraction from the riverbed and the river bank has detrimental impacts on the environment and river geomorphology. …”

Waterlogging Simulation and Drainage Effect Assessment of Deep Tunnel Engineering in a Coastal City Based on MIKE by TAN Yin, TU Xinjun, YU Honggang, LIN Kairong, LIU Meixian, MA Ke

“…Taking the western region of Shenzhen City in the Guangdong-Hong Kong-Macao Greater Bay Area as the study area, this paper couples a one-dimensional river flood model, a pipeline drainage model, and a two-dimensional overland flow model to simulate urban waterlogging processes under extreme precipitation and typical storm surge. …”
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Experimental Study of Blast-Induced Vibration Characteristics Based on the Delay-Time Errors of Detonator by Ping Wang, Yuanjun Ma, Yongjian Zhu, Jun Zhu

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Test Study on Airtight Capability of Filter Cakes for Slurry Shield and Its Application in a Case by Fanlu Min, Wei Zhu, Shengquan Xia, Rui Wang, Daiwei Wei, Teng Jiang

“…The slurry formulation and airproofing value of filter cakes obtained in the tests were applied successfully in Nanjing Yangtze River Tunnel.…”
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Spatiotemporal Variation Characteristics of Dry/Wet Spells in Longitudinal Range-Gorge Region of the Tropic of Cancer by JIN Hanyu, CHENG Qingping, REN Yitong

“…Under the background of global warming,extreme climate events occur frequently.Understanding the change in precipitation from multiple perspectives is of great significance to the utilization of water resources.Specifically,the daily precipitation data at 24 stations along the Tropic of Cancer in the Longitudinal Range-Gorge Region (LRGR) from 1961 to 2019 are used to calculate 14 wet/dry spell indices.Methods including the revised Mann-Kendall test,Pettitt,and wavelet coherence are adopted to reveal the spatiotemporal variation characteristics of the dry/wet spell indices and their correlation with the large-scale circulation index.The results indicate that:① the wet and dry spells in LRGR of the Tropic of Cancer show a significant decreasing and increasing trend,respectively,especially in the area west of Yuanjiang River and south of the Tropic of Cancer.The change in the wet and dry spell indices of most stations is mainly concentrated in 2002.② The frequency of short-duration wet spells and the contribution rate to annual precipitation demonstrate an increasing trend,and those of the medium-long-duration wet spells demonstrate a decreasing trend;the short-duration dry spells are in decline while medium-long-duration dry spells are rising,and the entire region tends to aridification.③ The extreme dry spell index is closely related to ENSO,and it has a negatively correlated co-occurrence cycle of about six years;the extreme wet spell index is closely related to the summer monsoon of the South China Sea,and it has a positively correlated co-occurrence cycle of about eight years.To sum up,the above analysis shows that dry and wet spell indices in LRGR of the Tropic of Cancer demonstrate an overall trend of aridification,which means that the drought risks are increasing.Their spatiotemporal variation characteristics and local differences may be closely related to the joint influence of the large-scale circulation index,monsoon,and channel-blocking in LRGR.…”
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Recalculating national occurrence of microplastics in China’s freshwater by Dongyu Xu, Bo Gao

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Preliminary Evaluation of Some Engineering Geological Properties of Soils in the New Yenagoa Town, Bayelsa State, Central Niger Delta by PO Youdeowei, HO Nwankwoala

“…The boreholes were spaced 100m apart along the 1.2 km long river channel and drilled down to a maximum of 10m. …”
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VMLP neural network design using optimization algorithms to predict spider suspend (Case Study: Watershed Dam Kardeh) by masooume darmani, mohammad nohtani, haydeh ara, Ali golkarian, Salman Sharif Azari

“…One of the most important processes of erosion and sediment transport in streams is the river most complex engineering  issues.this process special effects on water quality indices, action suburbs floor and destroyed much damage to the river and also into the development plans  Lack of continuity sediment sampling and measurement of many existing stations. due to the low number of hydrometric stations in Iran and the lack of continuity of sediment sampling and measuring in many existing stations, on one hand the exact amount of sediment load in many rivers in the country is not available and because of differences in climatic, hydrological and topographical conditions in the country, on the other hand, the preparation and calibration of sediment Erosion Models different regions, is unavoidableCalibration models of erosion and sedimentation in different locations is difficult and requires financial capital andthe time . the But evolutionary optimization algorithm able to resolve this problems of mathematical and experimental methods in this paper, a new optimization algorithm spiders can be made to education And the evolutionary pattern for input (discharge and precipitation) and rain-gauge gauging stations and Watershed Kardeh designated evolutionary algorithms and artificial network performance for 24 year 24-year dam catchment Kardeh for the period studied. …”
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Assessment of Artificial Intelligence Models for Developing Single-Value and Loop Rating Curves by Majid Niazkar, Mohammad Zakwan

“…Estimation of discharge flowing through rivers is an important aspect of water resource planning and management. …”
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Urban Land Subsidence Characteristics and Their Relationship with Locations Liable to Waterlogging Based on SBAS-InSAR by LIU Huanyu, WU Zhen, YU Huanghao, CHEN Guangcheng, XIAO Yang, LI Kuang, LI Binquan

“…The results show that: ① the average subsidence rate in Nansha District is 1.363 mm/a, and the subsidence area is mainly located in the river bank, construction area, and reclamation area. …”
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A New Concept Proposal of the Tidal Level Designed for the Security of Coastal Levee during Storm Surge — Taking the Lingdingyang Estuary as an Example by LI Bin, HE Yong, FANG Shenguang

“…Based on the analysis of the design frequency tidal levels,storm surge water increase and flood inflow upstream of control stations in Lingdingyang Estuary over years,it showed that the tidal levels of designed frequency of 0.5%~2.0% raised from 0.2 to 1.0 m in recent years,the extreme storm surge elevations exceed 2.5 m commonly,and the current tidal level difference of adjacent design frequency was less than 0.2 m.During the emergence of the extreme storm surge elevation in the estuary flood upstream would not be appeared simutaneously,while the moderate tide was most likely encounterred.Therefore,there were some problems in the application of design frequency tidal levels in estuarine waters,such as the small tidal level difference between adjacent frequencies,the severe frequency jump of tide level during strong typhoon,and the failure to directly reflect the leading role of the extreme storm surge elevation in the elevation design of coastal levee.The concept of the tidal levels designed for storm surge security of coastal levee was proposed in the paper,which were composed of multi-year average high tidal level and the maximum extreme storm surge elevation,clearly and easily to be used.It highlights the main role played by coastal levee to resist the disaster by strong storm surge.The calculated values were close to and slightly more than the designed tidal levels of 100~200 year return period of main stations in the mouth of Lingdingyang estuary,Shiziyang water area and delta river network area after reviewed in 2020,proving its safety and reliability.The reviewed tidal levels of designed frequency in the Chiwan station in 2020 were likely too high by analysis preliminarily.The tidal level designed for storm surge security of coastal levee could be widely used in reinforcement design,safety risk assessment in storm surge and storm surge disaster warning and response.…”
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Two-dimensional flood model for risk exposure analysis of land use/land cover in a watershed by G. Puno, R. Puno, I. Maghuyop

“…The process involved utilizing a high-resolution digital elevation model and a set of high-precision instruments such as the real-time kinematic-global position system receiver, digital flow meter, deep gauge, and automatic weather station in collecting the respective data on bathymetry, river discharge, river depth, and rainfall intensity during a particular climatic event, needed for the model development, calibration and validation. …”
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Characteristics of runoff changes and their climatic factors in two different glacier-fed basins by Sun Zhenqi, Wang Shijin, Li Zhongqin

“…This study took the Yanggong River Basin (YRB) and Urumqi River Basin (URB) as two typical cases, to explore the runoff change differences and their responses to climate factors from 1979 to 2017. …”
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Short-Term Optimal Scheduling Method of Cascade Hydropower Stations Based on Segmented Load Construction Strategy by LI Chonghao, LI Shushan, TANG Hongbing, LIU Huan, MA Xiangyu, LIAO Shengli

“…With the rapid development of China's economy,electricity demand has increased.As the largest clean energy in China,hydropower has been put into large-scale and centralized production,and the most complex large-scale hydropower system in the world is formed.However,short-term hydropower optimal scheduling faces the serious challenge of the curse of dimensionality due to massive cascade hydropower stations,numerous hydropower constraints,and time-sensitive scheduling requirements.Therefore,this paper proposes a short-term optimal scheduling method for cascade hydropower stations based on a segmented load construction strategy.First,the selection rules of the hydropower stations to be regulated are formulated from the perspective of the regulation performance,location,and task of the cascade hydropower stations.Then,a method is given to divide the complex original load into two sub-load processes,namely the segmented load process with time reduction scale and the residual load process with frequent fluctuations.Finally,the adjustment method is given,and the particle swarm algorithm is used for traversal and optimization at different stages,so as to find the load division process when the target is optimal.By taking seven cascade hydropower stations in a certain river basin in southwest China as research objects,a mature particle swarm algorithm is used to simulate the typical day during the flood and dry periods.The results show that the segmented load construction strategy proposed in this paper can effectively reduce the solution complexity,and the appropriate number of segments can improve the solution efficiency while ensuring the solution quality.In addition,this method greatly reduces the output fluctuation of auxiliary hydropower stations and helps to reduce the difficulty of scheduling and unit loss.Therefore,the method proposed in this paper can provide a reference for solving the short-term scheduling of large-scale cascade hydropower stations and is of good practical value.…”
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A New Approach for Probabilistic Risk Assessment of Ship Collision with Riverside Bridges by Wei Zhang, Shuoyu Liu, Wenwen Luo, Liping Wang, Bo Geng, Zhenxing Zheng

“…The configuration of riverside bridges, such as the spatial distribution, wading status, and ship accessibility of piers, is generally different from river-crossing bridges. Thus, the ship collision risk of riverside bridges cannot be assessed using conventional assessment methods applicable to river-crossing bridges. …”
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Study of Macro- and Mesodamage of Remolded Loess under Alternating Dry and Wet Conditions in an Acid Rain Environment by Wanjun Ye, Yuntao Wu, Yang Bai

“…As a national development plan, ecological protection of the Yellow River Basin has attracted extensive social attention in recent years. …”
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Influence of Balance Hole Diameter on Leakage Flow of the Balance Chamber in a Centrifugal Pump by Wei Dong, Diyi Chen, Jian Sun, Yan Dong, Zhenbiao Yang, Junle Yan

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Discerning Natural and Anthropogenic Factors Driving the Variation of Estuarine CH4 and N2O by Zhengping Chen, Liuqian Yu, Qichun Yang, Qixing Ji

“…In this study, biweekly sampling was conducted from November 2021 to January 2024 at the main outlet of the Pearl River in south China, which is characterized by a subtropical climate, a eutrophic environment, and heavy anthropogenic activity. …”
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Deteksi Pencemaran Mikroplastik pada Air Lindi di TPA Piyungan Yogyakarta Indonesia by Inggita Utami, Agustina Agustina

“…Therefore, the Yogyakarta government needs to increase the leachate processing process to decompose this microplastic and not pollute the Opak river as a leachate disposal channel for the Piyungan landfill.…”
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