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Sedimentation in the harbors’ basins is an environmental phenomenon that frequently disrupts safe shipping and necessitates costly dredging operations. The layout of harbors and the permeability of protective structures such as breakwaters influence sediment transport within harbor basins. Thus, through a multistep framework, this study investigates the sedimentation management issues for the Egyptian proposed Ezbet Elborg fishing harbor based on field measurements and a numerical morphodynamic coastal modeling system (CMS). First, field measurements were analyzed and evaluated for acquiring a full grasp of the research area’s bathymetry and hydrodynamics. Second, a two-dimensional (2D) numerical simulation CMS model was set up and calibrated against field measurements wherein the developed CMS model highly correlated with actual measurements by 97%. CMS results demonstrate that the predominant NNW wave with the formed longshore current on both the harbor’s sides affects sediment accumulation within the harbor’s basin. Third, 100 simulations for the proposed harbor including different structural modulation scenarios affecting the sedimentation issue were investigated via the calibrated CMS model. Finally, an exploratory data analysis (EDA) is performed via correlation matrix and ANOVA test for the CMS’s scenarios’ results to gain an in-depth view of the relation between the harbors’ layout and the structural characteristics with the sedimentation volumes. Results showed that breakwaters’ orientation affects sediment accumulation more than its length. Also, breakwater permeability and basin width are significantly affecting sediment accumulation. Ultimately, the current study makes a substantial contribution to integrated coastal structure management (ICSM) by helping coastal stakeholders to mitigate the negative impacts of the harbors’ sediment deposition aiming at sustaining both environmental and economic aspects.

With improving technology, the idea of using energy dissipater equipment has been strengthened in order to control the structures response in dynamic loads such as wind and earthquake. In this research, we dealt with seismic performance of base isolated structures with lead-rubber bearing (LRB) using incremental dynamic analysis (IDA). For this purpose, 3- and 9-story buildings have been utilized in the SAC project undergoing 22 earthquake records which were far-fault. Plotting the fragility curve for various states of design time period and isolator damping of LRB, it is observed that, by increasing damping, the isolator has not been activated in small spectrum acceleration, which shows that the annual exceedance probability is increased in immediate occupancy (IO) performance level and decreased in life safety (LS) performance level. The results show the reduction of determined failure probability in fragility curves for two levels of performance of uninterrupted use and lateral safety. Likewise obtained results show that, with increasing design time period of isolator, the amount of failure probability is decreased rather than the isolator with smaller design time period, for both LS and IO states. And the isolator illustrates better performance.

Evaporation estimation is very essential for planning and development of water resources. The study investigates the ability of new method, dynamic evolving neural-fuzzy inference system (DENFIS), in modeling monthly pan evaporation. Monthly maximum and minimum temperatures, solar radiation, wind speed, and relative humidity data obtained from two stations located in Turkey are used as inputs to the models. The results of DENFIS method were compared with the classical adaptive neural-fuzzy inference system (ANFIS) by using root mean square error (RMSE), mean absolute relative error (MARE), and Nash-Sutcliffe Coefficient (NS) statistics. Cross validation was applied for better comparison of the models. The results indicated that DENFIS models increased the accuracy of ANFIS models to some extent. RMSE, MARE, and NS of the ANFIS model were increased by 11.13, 11.45, and 6.83% for the Antalya station and 20.11, 12.94%, and 8.29% for the Antakya station using DENFIS.

This study investigates predicting the pullout capacity of small ground anchors using nonlinear computing techniques. The input-output prediction model for the nonlinear Hammerstein-Wiener (NHW) and delay inputs for the adaptive neurofuzzy inference system (DANFIS) are developed and utilized to predict the pullout capacity. The results of the developed models are compared with previous studies that used artificial neural networks and least square support vector machine techniques for the same case study. The in situ data collection and statistical performances are used to evaluate the models performance. Results show that the developed models enhance the precision of predicting the pullout capacity when compared with previous studies. Also, the DANFIS model performance is proven to be better than other models used to detect the pullout capacity of ground anchors.

This study introduces the analysis of structural health monitoring (SHM) system based on acceleration measurements during an earthquake. The SHM system is applied to assess the performance investigation of the administration building in Seoul National University of Education, South Korea. The statistical and wavelet analysis methods are applied to investigate and assess the performance of the building during an earthquake shaking which took place on March 31, 2014. The results indicate that (1) the acceleration, displacement, and torsional responses of the roof recording point on the top floor of the building are more dominant in the X direction; (2) the rotation of the building has occurred at the base recording point; (3) 95% of the energy content of the building response is shown in the dominant frequency range (6.25–25 Hz); (4) the wavelet spectrum illustrates that the roof vibration is more obvious and dominant during the shaking; and (5) the wavelet spectrum reveals the elasticity responses of the structure during the earthquake shaking.

This study investigates a novelty wavelet application for damage detection of regular and irregular building structures under seismic load effects. The energy of wavelet transform and correlation coefficient are used to detect the performance of the damaged building. The simple 3D regular and irregular simulation (finite element model) models of a building are designed to verify the methods’ uses and optimum applications. The obtained results reveal that the energy of Discrete Wavelet Transform (DWT) shows significantly higher performance than the energy of Continuous Wavelet Transform (CWT) in detecting the damage of the building, and the performance of irregular buildings appeared suitable for use in the seismically active areas. In addition, it can be concluded that the correlation coefficient can be applied to study the effects of damage and the safety of structures.

Capillary pressure-water saturation relations are required to explore the CO2/brine flows in deep saline aquifers including storage capacity, relative permeability of CO2/brine, and change to stiffness and volume. The study on capillary pressure-water saturation curves has been conducted through experimentation and theoretical models. The results show that as the pressure increases up to 12 MPa, (1) capillary pressure-water saturation curves shift to lower values at given water saturation, (2) after the drainage process, residual water saturation decreases, and (3) after the imbibition process, capillary CO2 trapping increases. Capillary pressure-water saturation curves above 12 MPa appear to be similar because of relatively constant contact angle and interfacial tension. Also, as brine salinity increases from 1 M to 3 M NaCl, (1) capillary pressure-water saturation curves shift to lower capillary pressure, (2) residual water saturation decreases, and (3) capillary CO2 trapping increases. The results show that pressure and brine salinity have an influence on the capillary pressure-water saturation curves. Also, the scaled capillary CO2 entry pressure considering contact angle and interfacial tension is inconsistent with atmospheric conditions due to the lack of wettability information. Better exploration of wettability alteration is required to predict capillary pressure-water saturation curves at various conditions that are relevant to geological CO2 sequestration.

This paper mainly deals with seismic response and performance for self-centering friction damping braces (SFDBs) subjected to several maximum- or design-leveled earthquake ground motions. The self-centering friction damping brace members consist of core recentering components fabricated with superelastic shape memory alloy wires and energy dissipation devices achieved through shear friction mechanism. As compared to the conventional brace members for use in the steel concentrically braced frame structure, these self-centering friction damping brace members make the best use of their representative characteristics to minimize residual deformations and to withstand earthquake loads without member replacement. The configuration and response mechanism of self-centering friction damping brace systems are firstly described in this study, and then parametric investigations are conducted through nonlinear time-history analyses performed on numerical single degree-of-freedom spring models. After observing analysis results, adequate design methodologies that optimally account for recentering capability and energy dissipation according to their comparative parameters are intended to be suggested in order to take advantage of energy capacity and to minimize residual deformation simultaneously.

In situ damage detection and localization using real acceleration structural health monitoring technique are the main idea of this study. The statistical and model identification time series, the response spectra, and the power density of the frequency domain are used to detect the behavior of Yonghe cable-stayed bridge during the healthy and damage states. The benchmark problem is used to detect the damage localization of the bridge during its working time. The assessment of the structural health monitoring and damage analysis concluded that (1) the kurtosis statistical moment can be used as an indicator for damage especially with increasing its percentage of change as the damage should occur; (2) the percentage of change of the Kernel density probability for the model identification error estimation can detect and localize the damage; (3) the simplified spectrum of the acceleration-displacement responses and frequencies probability changes are good tools for detection and localization of the one-line bridge damage.

A three-dimensional (3D) modeling approach to investigate nonlinear seismic response of a curved and skewed bridge system is proposed. The approach is applied to a three-span curved and skewed steel girder bridge in the United States. The superstructure is modeled using 3D frame elements for the girders, truss elements for the cross-frames, and equivalent frame elements to represent the deck. Spherical bearings are modeled with zero-length elements coupled with hysteretic material models. Nonlinear seismic responses of the bearings subjected to actual ground motions are examined in various directions. Findings indicate that the bearings experience moderate damage for most loading scenarios based on FEMA seismic performance criteria. Further, the bearing responses are different for the loading scenarios because of seismic effects caused by interactions between excitation direction and radius of curvature.

Premise of the study: Microsatellite loci were developed for a monotypic species endemic to subtropical China, Cyclocarya paliurus, to help infer the evolutionary histories of ancient monotypic genera in subtropical China. Methods and Results: Using the Fast Isolation by AFLP of Sequences Containing repeats (FIASCO) protocol, 28 primer sets were identified in two wild populations. All loci were polymorphic, with the number of alleles per locus ranging from two to eight. The expected and observed heterozygosities ranged from 0.153 to 0.802 and from 0 to 0.750, respectively. The transferability of the 28 primer pairs was tested on Juglans regia, Pterocarya stenoptera, and Platycarya strobilacea. Twenty-one (75.0%), 22 (78.6%), and 15 (53.6%) markers were successfully amplified in J. regia, P. stenoptera, and P. strobilacea, respectively. Conclusions: These loci will be useful for in-depth analysis of genetic diversity and phylogeographical variation throughout the distribution range of C. paliurus.

In the near-field earthquake, forward directivity effects cause long-period pulse with a short effective time and a large domain in the velocity time history. This issue increases the ductility needs of structures, and in recent decades, the destructive effects of these kinds of records have been evaluated in comparison with far-field earthquakes. This brings about the necessity to compare a structure’s behavior subjected to vertical components of near-field (NF) earthquakes, including forward directivity effects vs. the effects of vertical components of far-field (FF) earthquakes. The present study investigated 3-, 5-, 8-, and 20-story steel moment frames with special ductility (SMF) through which modeling effects of panel zone have been applied, subjected to vertical component of near-field (NF) earthquakes with forward directivity and the vertical component of far-field earthquakes. By investigating the results, it can be clearly seen that the average values of the maximum displacement, shear force of the stories, and the velocity of each story under the impact of the near-field earthquake are greater than the amount of that under the effect of a far-field earthquake. However, this comparison is not valid for the amount of acceleration, axial force, and moments in the columns of the structures accurately.

One of the main driving factors for structures’ evaluation is the foundation settlement. Measuring structures’ settlement in field is costly especially when heavy loads are applied. Settlement prediction models can be used to avoid the high cost of settlement field tests. Four advanced heuristic regression methods are developed and applied in this study to estimate raft foundations’ settlement, namely, multivariate adaptive regression splines (MARS), M5 model tree (M5Tree), generalized regression neural networks (GRNN), and support vector regression (SVR) techniques. Simulation of raft pile foundations is utilized to calculate the settlements of piles under the effect of static and dynamic loads. Previous studies are compared with the newly developed models. The results show that the four models can be used to accurately predict foundations’ settlements in the training stage. Also, the results reveal that the MARS and SVR models performed slightly better than the M5Tree and GRNN models in the testing stage and accordingly can be used to predict foundations’ settlement. The SVR model outperformed other models when few numbers of measurements are available.

The bridge bearing is one of the component members which provide resting supports between piers and decks. The bridge bearing is intended to control longitudinal movement caused by traffic flow and thermal expansion, thereby reducing stress concentration. In high seismicity area, the bridge bearing has been utilized as the base isolation system to mitigate acceleration transferred from the ground. Although the existing bridge bearing installed between superstructure and substructure provides extra flexibility to the base of the entire structure, considerable permanent deformation occurs due to lack of recentering capacity after earthquake. It is required to spend extra cost for repairing impaired parts. The bridge bearings integrated with superelastic shape memory alloy (SMA) devices used for upgrading the recentering effect into the friction damper are proposed in this study. The refined finite element (FE) analyses are introduced to reproduce the response of such new structures under cyclic loading condition. The bridge bearing systems that maintain uniform recentering capability are designed with various friction coefficients so as to examine energy dissipation and residual deformation through FE analyses. After observing FE analysis results, optimal design for the recentering bridge bearing system will be proposed to take advantage of energy dissipation and self-centering capacity.

Objective: To assess the effectiveness of antibiotic treatment in patients with amniotic fluid (AF) "sludge" during the second or third trimester with uterine contractions and intact membranes., Methods: A retrospective cohort study was conducted of women at 15-32 weeks of pregnancy with uterine contractions and intact membranes. Women with AF "sludge" were treated with an antibiotic regimen of ceftriaxone, clarithromycin, and metronidazole. Based on changes in AF "sludge," patients were divided into group A (disappearance of "sludge") and group B (persistent "sludge")., Results: Women in group A (n=30) delivered later than those in group B (n=28). Group A showed a smaller initial size of "sludge" than group B (all P<0.05). Women in group A had a lower rate of preterm birth within 7 days, and before 28, 32, and 34 weeks of pregnancy, and composite neonatal morbidity and perinatal death than group B (all P<0.05)., Conclusion: The administration of antibiotics may eradicate AF "sludge" in women in the second or third trimester with uterine contractions and intact membranes, which are associated with the initial size of "sludge." Patients with disappearing "sludge" had more favorable pregnancy and neonatal outcomes than those with persistent "sludge.", (© 2020 International Federation of Gynecology and Obstetrics.)