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Abstract The Sporadic E layer or Es is an ionospheric phenomenon characterized by enhancements in electron density within 90–120 km above the Earth's surface. Based on the wind shear theory, the formation of Es layers is associated with vertical shears in the horizontal wind, in the presence of the Earth's magnetic field. This study explores the role of planetary waves on inducing these vertical shears and subsequently shaping Es layers. Our investigations benefit from a large amount of data facilitated by the FORMOSAT‐7/COSMIC2 and Spire missions, which offer extensive global coverage. A wave analysis is applied to the Es intensity as represented by the S4 index derived from radio occultation measurements, in search of potential planetary wave signatures. Additionally, measurements from Aura/MLS are used to analyze corresponding spectra for the geopotential height, enabling a comparative examination of planetary wave signatures in the Es layer and geopotential height variations. The findings reveal westward and eastward wave components with specific wavenumbers and periods, suggesting the involvement of westward propagating quasi 6‐day, quasi 4‐day planetary waves, and eastward propagating Kelvin waves with a period of around 3 days in Es layer formation at low latitudes.

Today, with the growth of the population and the increase in water, and air pollution, the issue of water purification and the use of nanomaterials has been the focus of many researchers. Considering that, environmental issues such as the reduction of pollutants in porous environments such as asphalt are important. Therefore, the aim of this research was to investigate the role of nanomaterials in improving flexibility and removing pollution in porous asphalt in urban surface runoff. For this purpose, titanium dioxide and graphene oxide nanoparticles were used to improve the mechanical performance of porous asphalt and to reduce the pollutants in the surface runoff. Hence, 11 samples were considered; first asphalt without nanomaterials was made, then 4 porous asphalt samples containing titanium dioxide nanoparticles and 4 porous asphalt samples containing graphene oxide nanoparticles with a concentration of 2-8% were made. The results of the flexible modulus test showed that the asphalt sample containing graphene oxide nanoparticles with a concentration of 6% performed best and was introduced as the optimal nano percentage, and in the environmental section, the asphalt sample containing titanium dioxide nanoparticles with a concentration of 8% was the best.

Water scarcity is one of the main challenges and constraints in the development of the country. On the other hand, wastewater treatment methods were initially developed as a response to concern about public health and the conditions caused by wastewater disposal in the environment, but now with the expansion of cities and urban life, keeping the environment clean and protecting it is essential for social life. Therefore, the aim of the research is to minimize the cost, optimize and simulate the primary sedimentation tanks in wastewater treatment plants using Flow3D software. In addition to evaluating the accuracy of the model in the simulation, parameters affecting the ratio of inlet through the overflow to the inlet under the valve were determined. The results showed that The Les model had better result in simulating the setting cavitiy in circular-shaped treatment plant tanks in comparison to the other turbulence models. Comparing the effect of settling characteristic parameters on the maximum settling depth, it was concluded that the drag coefficient and static angle parameters had a great effect on the it. According to several simulations performed with Flow3D software, it was found that this software has good accuracy in simulating the flow pattern passing through the circular overflow-valve treatment plant in both solid bed and mobile bed modes. Also, by comparing the effect of deposition characteristic parameters on the maximum deposition depth, it can be seen that the parameters of drag coefficient and static angle have a great effect on the amount of deposition. Also, among different turbulence models, LES model has more acceptable results in simulation. The settling of the refinery tanks indicates a circular Spillway-valve shape.

The investigation of sporadic E or Es layers typically relies on ground-based or satellite data. This study compares the Es layers recorded in ionograms with those detected using GNSS L1 signal-to-noise ratio data from FORMOSAT-3/COSMIC radio occultation at mid and low latitudes. GPS radio occultation measurements of Es layers, during an 11-year time span of 2007–2017, within a 2° latitude × 5° longitude grid around each ionosonde site are compared to the Es recordings of the ionosonde. By comparing multi-year radio occultation data with recordings from six ionosonde stations at mid and low latitudes, it was discovered that at least 20% of the Es layer detection results between each ionosonde and its crossing GPS radio occultation measurements did not agree. The results show that the agreement between the two methods in Es detection is highly dependent on the season and local time. This study suggests that Es layer recordings from ground-based ionosonde observations have the best agreement with the Es layers detected by radio occultation data during daytime and local summers. The difference in the Es detection mechanisms between the two methods can explain the inconsistency between Es events measured by these two methods. The detection of Es layers in ionograms relies on the high plasma concentration in the E region, whereas signal scintillations caused by a large vertical gradient of the plasma density in the E region are considered a sign of Es occurrence in satellite techniques.

Background and purpose: Today, hospital care, relying on the health record system, has received more attention than before. Considering the diversity of data in these systems, the design of standard conceptual and logical models by service providers will play an important role in their success. Therefore, this research was conducted with the aim of designing a logical data model of the hospital information management system for athletes based on international standards. Materials and methods: The design of the logical model of the hospital information system for athletes in Iran based on the main entities and components of the system was done after comparing the selected countries, the initial review of the needs of the beneficiaries, the dataset validated by the experts and the validation of the conceptual model, and the diagrams were painted. The meeting was held with the presence of experts to validate the proposed logical model. The proposed amendments were discussed and carried out in the meeting, the collective agreement on the presented logical model and the validity of the model were confirmed. Results: login activities, password change, examination appointment booking, athlete information registration, examination registration, test results registration, vaccination information registration activity, health reminder registration, and health information registration were determined as the main diagrams of this system. Conclusion: Based on the findings, it seems that access to sports medicine information is the key point, and a person can see and receive health needs related to him in a patient-centered treatment.

Abstract Sporadic E or Es is a transient phenomenon where thin layers of enhanced electron density appear in the ionospheric E region (90–120 km altitude). The neutral wind shear caused by atmospheric tides can lead ions to converge vertically at E-region heights and form the Es layer. This research aims to determine the role of atmospheric solar and lunar tides in Es occurrence. For this purpose, radio occultation data of FORMOSAT-3/COSMIC have been used, which provide complete global coverage of Es events. Moreover, GAIA model simulations have been employed to evaluate the vertical ion convergence induced by solar tides. The results show both migrating and non-migrating solar tidal signatures and the semidiurnal migrating lunar tidal signature mainly in low and mid-latitude Es occurrence. The seasonal variation of the migrating solar tidal components of Es is in good agreement with those in the vertical ion convergence derived from GAIA at higher altitudes. Furthermore, some non-migrating components of solar tides, including semidiurnal westward wavenumbers 1 and 3 and diurnal eastward wavenumbers 2 and 3, also significantly affect the Es occurrence rate. Graphical Abstract

Background In today's medical information system, various data are stored to be analyzed or retrieved when necessary. Therefore, this study was conducted to determine the needs of stakeholders of athletes' medical information management system based on international standards. Materials & Methods The study population included athletes, clinical service providers and managers of sports medicine centers in Iran. In this study, comparison tables of selected countries were used to assess the needs of stakeholders and were quantitative-descriptive. To analyze the data obtained from the questionnaire, the number of answers obtained for each component was determined based on the Likert scale and according to the frequency of answers related to the options, the percentage of each was calculated and the components that were more than 50% were agreed upon. Results Findings identified the initial data set, general components of the system and the initial assets of the Athlete Sports Medicine Information System. The results showed that the highest collective agreement about the presence of drug allergies and diabetes in the family's history was in the individual health records of athletes and the lowest agreement was reached on how to join the team. Stakeholder needs, compared to selected countries, included more details, including mental health information, that were not given much attention in the selected countries' datasets. Conclusion Based on the findings, it seems that a person's access to sports medicine information is a key point and a person can see and receive their information, problems and related health needs in a patient-centered treatment.

For years great interest has been taken in the effects of physical phenomena on ionosphere structure. A total solar eclipse was visible in North America on August 21st, 2017. This event offered a great opportunity for remote sensing the ionospheric behavior under the eclipse condition. In this study we investigated the effects of total solar eclipse on variations of Total Electron Content (TEC), and consequently deviations on regional models of Vertical TEC (VTEC), as well as variations in ionospheric scintillation occurrence. Although variations of TEC due to total solar eclipse are studied thoroughly by many authors, but the effect of solar eclipse on ionospheric scintillation has never been considered before. Our study is based on measurements from a high-rate GPS network over North America on the day of eclipse, a day before and after its occurrence, on the other hand, GPS measurements from ground-based stations on similar days were used to model TEC on the day of event, and also one day before and after it. The results of this study demonstrate that solar eclipse reduced scintillation occurrence at the totality region up to 28 percent and TEC values showed a decrease of maximum 7 TECU. Considering TEC models, our study showed apparent variations in the regional models, which confirms previous studies on ionospheric responses to eclipse as well as theoretical assumptions.

To investigate the seismic responses of dams due to ground non uniform displacements, the records of earthquake displacements are required. Such data is seldom recorded during a specific earthquake and in the most cases the recorded data in not sufficient for non-uniform analysis of a dam. In this study non uniform accelerations are generated using Kanai-Tajimi spectrum with considering wave passage, incoherent effects and coherence spectrum model. A 3-d finite element model of dam-foundation of Karun 4 arch dam as the highest dam in Iran is modeled. The model is analyzed under uniform and non-uniform generated accelerations and its responses are investigated. The results show that, non-uniform excitation leads to differences in seismic response than uniform excitation on dam. It is indicated that considering non-uniform excitation in seismic analysis increases the stresses and displacements on the dam body. To investigate the seismic responses of dams due to ground non uniform displacements, the records of earthquake displacements are required. Such data is seldom recorded during a specific earthquake and in the most cases the recorded data in not sufficient for non-uniform analysis of a dam. In this study non uniform accelerations are generated using Kanai-Tajimi spectrum with considering wave passage, incoherent effects and coherence spectrum model. A 3-d finite element model of dam-foundation of Karun 4 arch dam as the highest dam in Iran is modeled. The model is analyzed under uniform and non-uniform generated accelerations and its responses are investigated. The results show that, non-uniform excitation leads to differences in seismic response than uniform excitation on dam. It is indicated that considering non-uniform excitation in seismic analysis increases the stresses and displacements on the dam body.

In this research, due to the importance of identifying the mechanisms affecting the scouring on this types of bridge piers, the effect of the geometric shape of the piles installed under the inclined piers and also the effect of the pile cap leveling in the sedimentary bed have been investigated and the properties of the scouring around the inclined pier group was studied numerically using the FLOW-3D software. The study of total shear stress in the flow bed at different leveling of the pile caps shows that the highest shear stress is created when the pile cap position is at the same level as the river bed; by installing the pile cap at a lower level than the river bed, the maximum shear stress decreases. This may be due to the fact that in this case, the distance between the pier group increases and the presence of the second pier decreases the flow rate in the pier group and different pier in the one pier group acts as the two independent piers in the formation of the flow pattern. By comparing the final longitudinal sections of the scouring at different leveling of the pile cap, it is concluded that the largest reduction in scouring depth occurs in aerofoil-shaped pile caps and pile caps with the sharper nose and better aerodynamic shapes are good options to control the horseshoe vortices and will reduce the scouring depth around the inclined pier group.

This research reviews recent advances in the domain of Automated Rule Checking (ARC) and argues that current systems are predominantly designed to validate models in post-design stages, useful for applications such as e-permitting. However, such a design-check-separated paradigm imposes a burden on designers as they need to iteratively fix the fail-to-pass issues. Accordingly, the study reviews the best-practices of IFC-based ARC systems and proposes a framework for ARC system development, aiming to achieve proactive bottom-up solutions building upon the requirements and resources of end-users. To present and evaluate its capabilities, the framework is implemented in a real-life case study. The case study presents all the necessary steps that should be taken for the development of an ARC solution from rule selection and analysis, to implementation and feedback. It is explained how a rule checking problem can be broken down into separate modules implemented in an iterative approach. Results show that the proposed framework is feasible for successful implementation of ARC systems and highlight that a stable data standard and modeling guideline is needed to achieve proactive ARC solutions. The study also discusses that there are some critical limitations in using IFC which need to be addressed in future studies.

The aim of this study is the evaluation of electron dose enhancement and photon contamination production by various nanoparticles in the electron mode of a medical linac. MCNPX Monte Carlo code was used for simulation of Siemens Primus linac as well as a phantom and a tumor loaded with nanoparticles. Electron dose enhancement by Au, Ag, I and Fe2O3 nanoparticles of 7, 18 and 30 mg/ml concentrations for 8, 12 and 14 MeV electrons was calculated. The increase in photon contamination due to the presence of the nanoparticles was evaluated as well. The above effects were evaluated for 500 keV and 10 keV energy cut-offs defined for electrons and photons. For 500 keV energy cut-off, there was no significant electron dose enhancement. However, for 10 keV energy cut-off, a maximum electron dose enhancement factor of 1.08 was observed for 30 mg/ml of gold nanoparticles with 8 MeV electrons. An increase in photon contamination due to nanoparticles was also observed which existed mainly inside the tumor. A maximum photon dose increase factor of 1.07 was observed inside the tumor with Au nanoparticles. Nanoparticles can be used for the enhancement of electron dose in the electron mode of a linac. Lower energy electron beams, and nanoparticles with higher atomic number, can be of greater benefit in this field. Photons originating from nanoparticles will increase the photon dose inside the tumor, and will be an additional advantage of the use of nanoparticles in radiotherapy with electron beams.