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Understanding the long-term performance of bridges plays a major role in the selection of appropriate asset-management strategies, which eventually reduce life-cycle costs and extend the service life of a bridge. To understand bridge performance better, the Federal Highway Administration initiated a research project utilising accelerated testing of full-scale bridge superstructure systems subjected to cyclic moving wheel loads and freeze–thaw environmental conditions. As part of the research project, complementary non-destructive evaluation (NDE) techniques were used to assess the performance of a full-scale bridge deck during the curing and loading period. NDE results, shortly after construction, revealed a smaller cover depth of rebars in the middle section of the deck. This has likely created a preferential path for the subsequent deterioration of the deck. It was suggested to use a scaled version of the electrical resistivity (ER) values to improve the consistency between temporal ER measurements of the deck, and it was shown that combining construction information with NDE results can improve the interpretation of results. Overall, the results showed the importance of NDE for quality assurance of new construction and provided a better understating of the long-term bridge deck performance.

Binding interaction of two organoplatinum complexes, [Pt(C^N)Cl(dppa)]

In this study, a new optimization algorithm is proposed based on swarm intelligence theory. In the algorithm, the movement of each individual toward the best member of the population is not represented as a linear vector; instead, it can change nonlinearly according to the discrete-time that is represented by the iteration number. By implementing this change, the speed of each member of the population can be controlled, which results in finding a better solution. As there is a dependency on the iteration number, it is named the Iteration Dependent Optimizer (IDO). The performance of the proposed algorithm is evaluated based on unconstrained unimodal and multimodal benchmark functions and constrained engineering optimization problems. Then the algorithm is used to solve a practical problem in civil engineering, in which unknown parameters of the model of a large-scale magnetorheological (MR) damper, which is commonly used in structural control, are identified. The results of statistical study and direct comparisons demonstrate the advantages and capabilities of the proposed model and indicate that IDO can compete favorably with some other well-studied algorithms.

Background Before antibiotics were available, X-ray therapy was used to treat pneumonia, but its effectiveness is unknown. It was not fully understood how low-dose radiation could reduce inflammation in early attempts to treat pneumonia with X-rays. Exposure to low-dose radiation therapy (LDRT) may activate anti-inflammatory molecules such as TGF-b1 and IL-10. This systematic review and meta-analysis aimed to determine whether LDRT effectively treats COVID-19-associated pneumonia. Methods This study followed the PRISMA guidelines (Principles for Reporting Systematic Reviews and Meta-Analyses). A search was conducted on Google Scholar and PubMed for articles published before June 12, 2022. The Newcastle–Ottawa Scale (NOS) was used to evaluate the included research quality. Results In these studies, patients were given lung radiation at doses ranging from 0.5 to 1.5 Gy. Except for one study, all clinical, radiological, and survival outcomes improved. The study showed that whole-lung radiation at doses of 0.5–1.5 Gy was beneficial to patients with COVID-19-associated pneumonia who were oxygen-dependent. In these studies, the reported SR was 59% (95% CI, 44–75%). Conclusions LDRT has the potential to be a viable therapy option, although large-scale randomized trials are necessary, particularly in the elderly, who are more at risk of mortality from COVID-19.

Global technological advancements drive daily energy consumption, generating additional carbon-induced climate challenges. Modifying process parameters, optimizing design, and employing high-performance working fluids are among the techniques offered by researchers for improving the thermal efficiency of heating and cooling systems. This study investigates the heat transfer enhancement of hybrid "Al

One of the main approaches for performance improvement of thermal power plants is employing preheating units. Preheating the air or stream in Brayton or Rankine cycles can significantly improve the overall efficiency output power. Solar energy, as an available renewable energy, is an attractive option to be employed as the source of preheating. In the present article, applications of solar energy for preheating air and steam in thermal power plants are reviewed. According to reviews, enhancement in the performance of the systems is under influence of several factors such as the configuration of reference system, operating condition, applied technology etc. Besides performance enhancement of the power plant, integration of solar preheating system can remarkably reduce the fuel consumption and consequently the emission of carbon dioxide. Furthermore, due to the unavailability of the solar energy in nigh and cloudy hours, applying thermal storage units can enhance the reliability of the system and increase contribution of solar energy in the output of the system.

A 1:15 3/4 open-jet scaled wind tunnel was used for experimental test. By arranging the synthetic jet actuator around the nozzle, the experimental method was used to analyze the flow field after the active flow control was implemented. The effects of the excitation frequency f J of different input signals and the excitation velocity V 0 of different jet nozzles on the jet shear layer and the flow field in the test section were studied. The obtained results showed that when the excitation frequency of the synthetic jet actuator ( f J ) was 40 Hz and excitation velocity ( V 0 ) equaled to 10 m/s, the turbulence intensity of each measurement point was the highest among all excitation frequencies, and the flow field had a peak near 19–20 Hz, which was the sensitive frequency of buffeting. The highest power spectral density of this frequency peak was nearly ten times higher than the original working condition, which meant that this control scheme will aggravate the buffeting phenomenon. For f J = 140 Hz and V 0 = 15 m/s, it only had a high PSD peak at 19–20 Hz near the measurement point 15 of the collector. The overall control effect of this scheme is better than other schemes. Therefore, it can significantly suppress the buffeting phenomenon of the wind tunnel and improve the flow field quality of the test section.

Introduction: Infertility, which is defined as the inability to conceive after one year of intercourse without the use of contraceptive methods, affects 15% of couples. 30-40% of the causes of male infertility are related to sperm disorders. The most common cause of infertility in men is their inability to produce enough healthy, active and active sperm, so the aim of this study was to determine the effect of ashwagandha powder on men with semen disorders. Materials and Methods: This study is a double-blind, clinical, randomized trial. Subjects were entered the study after obtaining informed consent and having inclusion and exclusion criteria. All subjects were clinically examined by a urologist. Blood and urine tests were also performed to ensure the health status of the individuals. Subjects did not take any PDE-V inhibitors or glucocorticoids, chemical, herbal and hormonal drugs for infertility treatment in the 4 weeks before the start of the study and until the end of the study. Finally, demographic information was obtained from all individuals and statistical calculations were performed using the statistical software SPSS. Results: In general, our results showed that the consumption of ashwagandha powder in the first experimental group was 41.3 ± 16.66% in the pre-test stage, 46.53±13.42% in the post-test stage and 45.5%±11.99% in the follow-up stage. These values were 41.23 ±19.85% in the placebo group of the pre-test stage, 41.0%±19.15 in the post-test stage and 40.37±19.41 % in the follow-up stage. This indicates that ashwagandha increased semen performance scores and sperm motility in different stages of the test compared to the second experimental group. Conclusion: The use of medicinal plants with male fertility enhancement properties can be used as a substitute or supplement for chemical drugs that affect male fertility. On the other hand, it is recommended that chemical drugs with fertility-reducing properties be less used or not used in men with infertility disorders.

Purpose The purpose of this study is to explore the heat transfer enhancement in copper–water nanofluid flowing in a diagonally vented rectangular enclosure with four discrete heaters mounted centrally on the sidewalls and a square-shaped embedded heated block in the influence of a static magnetic field. Design/methodology/approach Four discrete heaters are mounted centrally on each sidewall of the rectangular enclosure that embraces a heated square block. A static transverse magnetic field is acting on the vertical walls. The Navier–Stokes equations of motion and the energy equation are modified by incorporating Lorentz force and basic physical properties of nanofluid. The derived momentum and energy equations are tackled numerically using the successive over-relaxation technique associating with the Gauss–Seidel iteration technique. The effects of physical parameters connected to dynamics of flow and heat convection are explored from streamlines and isotherms graphs and discussed numerically in terms of Nusselt number. Findings The effect of the embedded heated square block size and its location in the enclosure, nanoparticles volume fraction and the intensity of the magnetic field on flow and heat transfer are computed. Compared with the case when no heated block is embedded in the enclosure, in free convection at Ra = 106, the average local Nusselt number on the wall-mounted heaters is attenuated by 8.25%, 11.24% and 12.75% when the enclosure embraced a heated square block of side length 10% of H, 20% of H and 30% of H, respectively. An increase in Hartmann number suppresses the heat convection. Research limitations/implications The enhancement in the convective heat is greater when the buoyancy effect dominates the viscous effects. Placing the embedded heated block near the inlet vent, the lower temperature zone has reduced while the embedded heated block is at the central location of the enclosure, the high-temperature zone has expanded. The external magnetic field can be used as a non-invasive controlling device. Practical implications The numerically simulated results for heat convection of water-based copper nanofluid agreed qualitatively with the existing experimental results. Social implications The models could be used in designing a target-oriented heat exchanger. Originality/value The paper includes a comparative study for three locations of the embedded heated square. The optimal results for the centrally located heated block are also performed for three different sizes of the embedded block. The numerically simulated results are compared with the published numerical and experimental studies.

Computational fluid dynamics is implemented to investigate the influence of the wheel contact patch on the global car aerodynamics. Two main aspects of the problem are the contact step and patch shape. Three important parameters: step height, cut angle, and tire tread shape are taken into consideration. For validations of the numerical results, the experimental data are also considered. The obtained results show that the step height may not significantly affect the global flow field. But when the cut angle increases, the flow separations on the two sides of the front wheel patch will be suppressed successively, which generates two critical points and a sudden drag decrease is achieved. Besides, tiny differences in tread shape can effectively change the flow rate of the underbody and make a huge drag discrepancy in the results. In conclusion, the cut angle and tire tread shape carefully must be dealt with in aerodynamic applications of automotive engineering.

The present study deals with computational investigation of natural convection in a porous chamber having a copper finned heat sink and a thermally producing element of finite thickness and heat conductivity. The enclosure is cooled from the external vertical and upper horizontal walls, whilst the remaining borders are considered to be thermally insulated. Newtonian and heat-conducting liquid with temperature-dependent viscosity is assumed as a working medium. Governing equations are written in non-dimensional variables «stream function—vorticity—temperature» and they are worked out by the finite difference technique. The temperature distribution, streamlines and the dependences of the integral characteristics on the governing characteristics, such as the Darcy and Ostrogradsky numbers and geometric characteristics of the radiator have been illustrated. Presented results can be used for the development of passive cooling systems.

In this article, the semi-analytical method known as the Differential Transform Method (DTM) for solving different types of differential equations is reviewed. First, basic definitions and formulas of DTM and Differential Transform-Padé approximation (DTM-Padé), which are used to increase the convergence and accuracy of DTM approximations, are discussed. Then both techniques of DTM and DTM-Padé, which have been successfully applied to partial differential equations, as well as the application of these methods in fluid mechanic and heat transfer are presented. In addition, the extension of DTM for integral differential equations and the fuzzy differential transformation method (FDTM) for fuzzy problems are discussed.

Two new functions on the semi-infinite interval, namely Rational Gegenbauer (R) and Exponential Gegenbauer (E) functions are proposed to solve the heat transfer problem. The considered problem is flow of MHD micropolar over a moving plate with suction and injection boundary conditions. For applying Tau method efficiently, two matrices of derivative and product for both of rational and exponential Gegenbauer whose enable us to solve a system of nonlinear algebraic equations on the semi-infinite interval were introduced, and an error bound of these functions approximation was estimated which led to have an exponential convergence rate in this method. Moreover, the influence of the important physical parameters on heat and mass transfer phenomena are studied with details. Comparing the results of Rational Gegenbauer Tau and Exponential Gegenbauer Tau methods with available analytical and numerical solutions shows that the present methods are efficient and have fast convergence rate and high accuracy. This method can solve a set of coupled nonlinear and high-order differential equations on a semi-infinite domain by converting to a set of linear equations.

Purpose The nanofluid natural convection heat transfer in a hollow complex enclosure, which is named as Shamse knot shape, is studied numerically. This paper aims to present how the Rayleigh number, nanoparticle volume fraction, Hartmann number and hollow side length affect the fluid flow and heat transfer characteristics. Design/methodology/approach The continuity, momentum and energy equations have been solved using lattice Boltzmann method (LBM). Numerical simulation has been obtained for a wide range of Rayleigh number (103 ≤ Ra ≤ 106), nanoparticle volume fraction (0 ≤ ϕ 0.05) and Hartmann number (0 ≤ Ha ≤ 60) to analyze the fluid flow pattern and heat transfer characteristics. Moreover, the effect of hollow side length (D) on flow field and thermal performance is studied. Findings The results showed that the magnetic field has a negative effect on the thermal performance and the average Nusselt number decreases by increasing the Hartmann number. Because of the high conduction heat transfer coefficient of nanoparticles, the average Nusselt number increases by rising the nanoparticle volume fraction. The effect of adding nanoparticles on heat transfer is more effective at low nanoparticle volume fraction (0 ≤ ϕ ≤ 0.01). It was also found that at Ra = 106, when the hollow side length increases to 3, the flow pattern becomes different due to the small gap. The averaged Nu is an increasing function of D at low Ra and an opposite trend occurs at high Rayleigh number. Originality/value For the first time, the effects of magnetic field, Rayleigh number, nanoparticle volume fraction and hollow side length on natural convection heat transfer of hybrid nanofluid (Ag-TiO2/water) is investigated in a complicated cavity.

An implicit finite difference scheme for the numerical solution of a generalized Black–Scholes equation is presented. The method is based on the nonstandard finite difference technique. The positivity property is discussed and it is shown that the proposed method is consistent, stable and also the order of the scheme respect to the space variable is two. As the Black–Scholes model relies on symmetry of distribution and ignores the skewness of the distribution of the asset, the proposed method will be more appropriate for solving such symmetric models. In order to illustrate the efficiency of the new method, we applied it on some test examples. The obtained results confirm the theoretical behavior regarding the order of convergence. Furthermore, the numerical results are in good agreement with the exact solution and are more accurate than other existing results in the literature.

Many studies have been done on the Pulsating heat pipes (PHP) using energy applications system. In this study a heat exchanger PHP is analyzed. A heat pipe prototype is manufactured for waste heat recovery. The present study experimentally investigated the effect of pulsating heat pipe on the waste heat recovery of the chimney and produce hot water for household consumption. The evaporator is placed in a smoke exhaust duct and the condenser is located in a water chamber in which the smoke heat is transferred through. The results are presented for different heat pipe angles to the horizon from 0 to 90. The PHP is filled 60% by distilled water as operating fluid. The highest hot water temperature in outlet of reservoir was about to 58 oC. Also, The CO2 mitigation and CPH of the waste heat recovery system was equal to 84.82 tons and 0.1$/m3. Moreover, the efficiency is changing from 19% for a horizontal PHP to 54% for a vertical one.

Since the commencement of the novel Coronavirus, the disease has quickly turned into a worldwide crisis so that there has been growing attention in discovering possible hit compounds for tackling this pandemic. Discovering standard treatment strategies is a serious challenge because little information is available about this emerged infectious virus. Regarding the high impact of time, applying computational procedures to choose promising drugs from a catalog of licensed medications provides a precious chance for combat against the life-threatening disorder of COVID-19. Molecular dynamics (MD) simulation is a promising approach for assessing the binding affinity of ligand-receptor as well as observing the conformational trajectory of docked complexes over time. Given that many computational studies are performed using MD along with the molecular docking on various candidates as antiviral inhibitors of COVID-19 protease, there is a demand to conduct a comprehensive review of the most important studies to reveal and compare the potential introduced agents that this study covers this defect. In this context, the present review intends to prepare an overview of these studies by considering RMSD, RMSF, radius of gyration, binding free energy, and Solvent-Accessible Surface Area (SASA) as effective parameters for evaluation. The outcomes will offer a road map for adjusting antiviral inhibitors, which can facilitate the selection and development of drug candidates for use in the medical therapy. Finally, the molecular modeling approaches rendered by this study may be valuable for future computational studies.

Thermal performance of energy conversion systems is one of the most important goals to improve the system’s efficiency. Such thermal performance is strongly dependent on the thermophysical features of the applied fluids used in energy conversion systems. Thermal conductivity, specific heat in addition to dynamic viscosity are the properties that dramatically affect heat transfer characteristics. These features of hybrid nanofluids, as promising heat transfer fluids, are influenced by different constituents, including volume fraction, size of solid parts and temperature. In this article, the mentioned features of the nanofluids with hybrid nanostructures and the proposed models for these properties are reviewed. It is concluded that the increase in the volume fraction of solids causes improvement in thermal conductivity and dynamic viscosity, while the trend of variations in the specific heat depends on the base fluid. In addition, the increase in temperature increases the thermal conductivity while it decreases the dynamic viscosity. Moreover, as stated by the reviewed works, different approaches have applicability for modeling these properties with high accuracy, while intelligent algorithms, including artificial neural networks, are able to reach a higher precision compared with the correlations. In addition to the used method, some other factors, such as the model architecture, influence the reliability and exactness of the proposed models.