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Understanding the dynamic response of floating breakwaters to wave forces is essential for optimizing their design and improving coastal protection. The response amplitude operator serves as a key parameter in accurately predicting the structural response amplitudes at different frequencies and wave angles. By incorporating this knowledge, adjustments can be made to enhance the effectiveness of floating breakwaters. In this study, a comprehensive 3D model of the mooring system is developed to simulate its behavior under various wave and current conditions. The model takes into account critical design factors such as pontoon shapes, anchor types, placements, and configurations. Through simulations, valuable insights are obtained regarding the performance of the wing-plate floating breakwater mooring system across different operational settings. These findings contribute to the optimization of floating breakwaters and their ability to protect coastlines from wave impacts.

Bridge agencies are often challenged to develop maintenance programs under given budgets. Numerous studies developed budget-allocation models for maintenance programs during defined planning horizons of multiple fiscal years while totally ignoring the crucial aspect of cash flow. The payment schedules (both timing and amount) for contractors might indicate agencies’ cash needs that exceed the available budgets during certain fiscal years, which create cash flow problems. While numerous finance-based scheduling (FBS) models were developed to manage cash flow for contractors, this function was totally overlooked for portfolio owners. Thus, this research reintroduces the FBS from the perspective of portfolio owners. A FBS model is developed to schedule the activities of the portfolio projects, utilize the schedules to define the payment schedules of projects’ contractors, calculate the agencies’ cash needs during the fiscal years, and utilize the multi-objective optimization algorithms of NSGA-II, SPEA-II, and MOPSO to optimize the projects’ schedules to achieve a balance between the cash needs during the fiscal years and the available budgets. The anticipated extensions in projects’ completion represent the conflicting objectives. Finally, the optimized schedules make the contractors’ payment schedules affordable by the agencies’ budgets, which help to complete projects successfully and achieve the programs’ strategic goals. [ABSTRACT FROM AUTHOR]

Encouraging sustainable mobility through sidewalk condition improvement is a critical concern for urban transportation. Sidewalk condition affects pedestrian safety, satisfaction, and mobility inclusiveness. Early sidewalk defect detection and repair ensure transport justice by addressing pedestrian inequality caused by walkability issues. This study presents novel Sidewalk Defect Detection Models (SDDMs) using computer vision to identify and delineate sidewalk defect boundaries accurately. The SDDMs provide a cost‐effective and efficient sidewalk inspection method, achieving high accuracy in recognizing defects for concrete and brick materials (mIoU of 0.91 and mAP of 0.99 for concrete, mIoU of 0.90, and mAP of 0.97 for brick). Integrated with Google Street View for data acquisition, it offers a rapid solution for monitoring sidewalk conditions remotely, promoting sustainability through timely repairs. This research provides significant advancements in urban planning and transport research, ultimately improving pedestrian safety and satisfaction. Thus, it makes human settlements more inclusive, safe, and sustainable. [ABSTRACT FROM AUTHOR]

The main objective of this study is to improve the performance of ultrafine dredged sand mortars by using metakaolin (MK) and silica fume (SF) mixed with high-content FA. The mechanical properties and microstructure of the ultrafine dredged sand mortars were analyzed. The results show that the strong growth rate of the mortars with 5%, 10%, and 15% MK and SF contents, respectively, exceeds 30% at the age of 7 d. Compared with an ordinary Portland cement dredged mortar, the shrinkage of the specimens with 5% and 15% MK increases prior to 7 d and decreases by 16.9% and 13.8%, respectively, at 90 d. The addition of MK shows a better enhancement effect than that of SF, with the splitting tensile strength increased by 41.4% to 2.15 MPa with 15% MK compared with the mortar with a 50% FA content at 3 d. MK shows a higher enhancement effect than SF due to its uniquely active Al2O3. Moreover, a microstructural investigation based on scanning electron microscopy (SEM) and mercury intrusion porosimetry (MIP) confirms that the physical filling and pozzolanic effects of MK and SF can optimize the microstructure of the slurry, improve the interfacial combination of different phases, and refine the pore size distribution of cement paste. The test results prove that high-content FA ternary cementitious systems containing MK or SF represent a sustainable solution to the resource utilization of building materials based on ultrafine dredged sand.

The compound impact of limited water accessibility, population growth, economic prosperity, and climate change are the leading causes of water scarcity in Texas and challenges to its long-term water management strategies. This study assesses surface and groundwater scarcities in Texas for past and future periods, using the water footprint concept in municipal and agricultural sectors. The US Geological Survey's monthly water balance model (MWBM) outputs were used to quantify the surface and groundwater availability under RCP4.5 and RCP8.5 climate change scenarios. Also, future water footprints in the agricultural and municipal sectors were calculated based on the 2022 Texas State Water Development Plan. The results indicate that the East Texas and Upper Coast climate divisions are projected to experience the maximum reduction in surface blue water availability. The projected decrease in groundwater availability will lead to substantial agricultural water scarcity in western climate divisions, especially in the High Plains and Trans-Pecos. In addition, the agricultural surface blue water scarcity will exceed 100% in the counties located at Lower Valley, and more groundwater scarcity will be observed at Trans-Pecos and High Plains. The municipal sector is projected to exhibit more than 100% water scarcity in limited counties. This water scarcity analysis integrates future hydrological shifts and water demands in Texas, highlighting critical areas where agricultural and urban water needs intersect and can be further extended to encompass a comprehensive socioeconomic evaluation. [ABSTRACT FROM AUTHOR]

This study was performed on the smoothhound shark: Mustelus mustelus (Linnaeus, 1758), during the period between December 2005 and April 2009, in the Eastern Levant along the Syrian coast. A total of 222 specimens examined (143 females, 79 males) discerned: The monthly sampling showed: the Smoothhound shark, M. mustelus were normally caught throughout the year, mainly in spring and summer, at fishing sites from Raas Albassit to Tartus city (34º. 40΄and 35º.80΄ N, 35º.70΄and 36º.05΄ E) of the Syrian coast, from shallow water to depth 250 m. The coefficient of void of total specimens stomachs was high (C.V=61.7 %), values were almost equal between males and females, the higher value recorded for adult females (C.V =62.5 %). The prey items belong to three collections: (Bony fish, Crustaceans, and Mollusks), bony fish occupy the first position for: Coefficient of feeding (Q=1560.4), Frequency of prey index (91.8 %), Gravimetric percentage of prey index (C.P=38.6 %). Crustaceans came in the first position for Numerical Percentage of Prey Index (C.N=45.6 %).

This study was carried out in the Marine Sciences Laboratory of Agriculture Faculty at Tishreen University, in collaboration with the Higher Commission for Scientific Research, on the Small Spotted Catshark Scyliorhinus canicula (Linnaeus, 1758) in the Syrian marine water (Eastern Levant of Mediterranean sea); From Rass Albassit northward ( 35° 55  N), to the Lebanese borders southward (°34 50´ N). During the period January 2012 to September 2013. 417 specimens (231 females, 186males) were collected at depths 50-250 m, from sandy or sandy-muddy bottoms by different fishing gears; mainly hook sub bottom. S. canicula suffers an overfishing into the Syrian marine water. The highest fishing quantity was during spring and summer. The total length of specimens ranged from 225 to 515 mm TL, and weighed from 22 - 380 g. Smallest specimens matured of males and females were 355, 350 mm, respectively. The total length ranged from 355 -500 mm TL for adult males, and 350 -515 mm TL for adult females. S. canicula is an oviparous species. The largest yolky oocytes diameter was 12 mm, and weighed 1.3 g. The ripe oocytes is covered and ovulated as an egg capsule. The length of egg capsules ranged from 42 -50 mm, their width from 16-18 mm, and their mass reached to 4.8 g.

This search focuses on the tensile and bending characteristics of a composite material that reinforced by various forms of fiberglass. Two fiber forms are considered; the first is bi-directional of (0°–90°) fiber direction, the second is random. The fiber thickness of bi-directional form has been investigated by considering thick and thin mats. The composite has been developed by hand lay-up process with a fiber weight ratio of 10%. Three samples of the developed composited have been compared with a base case sample (pure matrix of epoxy resin). Also, a microscopic vision has been captured on the fracture zone of tensile specimens. The results reveal that the random-form composite had maximum tensile strength and transverse stiffness, also, the thin-fiber composite showed maximum ductility.

Water scarcity as well as social and economic damages caused by the increasing amounts of non-revenue water in the water distribution networks (WDNs) have been prompting innovative solutions. A great deal of potable water is wasted due to leakage in the WDNs all over the world. Hence, various leak detection approaches have been explored, including the promising application of acoustic devices. Exploiting the benefits of technological advances in acoustic devices, signal processing, and machine learning (ML), this study aimed to develop a sophisticated system for leak detection in WDNs. Different from laboratory-based studies, this study was conducted on real WDNs in Hong Kong and lasted for about two years. Utilizing acoustic emissions acquired using wireless noise loggers, various ML algorithms were explored to develop inspection models for in-service and buried WDNs. ML classification algorithms can identify patterns in the acquired signals for leak and no-leak statuses. Thus, a combination of features describing acoustic signals in time and frequency domains was utilized to facilitate the development of ML models. Separately for metal and non-metal WDNs, ten well-known ML algorithms were used to develop leak detection models. The validation results demonstrate the promising application of noise loggers and ML for leak detection in real WDNs. Support Vector Machine (SVM), Artificial Neural Network (ANN), and Deep Learning (DL) leak detection models demonstrated a largely stable performance and a very good accuracy, particularly for new unlabelled cases. [ABSTRACT FROM AUTHOR]