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In this article, by using a novel approach, the heat transfer related to the hybrid nanofluid flow containing graphene oxide and copper particles in pure water, which is located in a rotating system, is analyzed. The innovation of this article, using a new approach, explores the heat transfer related to the flow of mixed nanofluid containing graphene oxide and copper particles in pure water, which is in a rotating system, and using the RBF method for the first time Investigates differential equations and simplified coupled equations. The radial basis function methodology was utilized to solve the equations, and the outcomes were compared to those obtained using the Runge –Kutta –Fehlberg numerical method. In this problem, there are much necessary quantities such as the Reynolds number, Nusselt number, Schmidt number, Thermophoretic quantity, Brownian quantity, Injection quantity, and Rotation quantity so that communication between them is investigated. Based on the results, with the increase of Reynolds number, the amount of heat transfer decreases significantly, and with the decrease of heat flows from the surfaces, the flow rate of fluid and nanofluid decreases. However, the concentration of nanomaterials reaches a maximum value as the Reynolds number increases.

Penelitian ini bertujuan untuk mengetahui peran oligarki lokal dan jaringannya dalam kebijakan pertambangan batubara serta menganalisis relasi bisnis dan politik sebagai jaringan patronase dan implikasinya terhadap dinamika ekonomi dan politik lokal di Kabupaten Tanah Bumbu, Kalimantan Selatan. Metode penelitian dalam artikel ini menggunakan pendekatan deskriptif kualitatif, yang dikerangkai dengan teori oligarki Winters dan Robison-Hadiz. Alasan memilih Kabupaten Tanah Bumbu sebagai lokasi penelitian, secara empiris wilayah ini menjadi epicentrum eksploitasi tambang dan lahirnya sejumlah oligarki lokal kroni kapitalis yang memiliki pengaruh bisnis dan kekuasaan. Hasil penelitian ini yaitu bahwa sejumlah perusahaan tambang batubara bukan saja sebatas aktivitas ekonomi-bisnis saja, akan tetapi telah merambah kepada wilayah politik kekuasaan. Artikel ini menyimpulkan bahwa sumber daya tambang batubara telah menjadi instrumen persekongkolan para aktor politik dan aktor bisnis (pengusaha tambang) untuk membangun jaringan patronase politik dan bisnis. Jaringan patronse politik dan bisnis semakin terstruktur. Pemilihan kepala daerah (Pilkada) langsung sebagai praktaik demokrasi pasca reformasi telah melahirkan transisi demokrasi yag memberikan ruang dan kesempatan bagi para aktor bisnis.

Abstract The main challenge for the advancement of current high-speed automotives is aerodynamic heating. In this study, the application of lateral jet for thermal protection of the high-speed automotives is extensively studied. The simulation of the lateral coolant jet is done via Computational fluid dynamic at high-velocity condition. Finding optimum jet configuration for reduction of the aerodynamic heating is the main goal of this research. Two different coolant jets (Helium and Carbon dioxide) are investigated as coolant jet and flow study and fuel penetration mechanism are fully presented. In addition, the thermal load on the main body of nose cone is compared for different configurations. Our results specify that the injection of lateral jet near the tip of spike is effective for thermal protection of main body via deflection of bow shock. Also, Carbon dioxide jet with lower diffusivity is more effective for the protection of forebody with multi-row disk from sever aerodynamic heating.

The principal moot point in this investigation is heat removal from surfaces with high heat flux, which is the use of tabulators and parts with a particular geometry, it has been chosen as a solution to this moot point. The primary hypothesis in this investigation is to increase fluid heat transfer by increasing turbulence and heat transfer by increasing the plane of heat transfer and establishing a vortex flow. The fundamental idea and novelty of this investigation is the simultaneous use of a turbulator (to improve turbulence and provide more effective heat transmission) and increasing the contact surface (through the installation of parts with unique geometry), which can be obtained from different turbulator used in other geometries. In this research, the limited volume method to solve governing equations in three-dimensional space and Cartesian coordinates has been used on the network using Ansys Fluent software. In order of comparison, turbulators SLT and then TRT is compared to other turbulators (TRT, SHT, RET) It has the highest Nusselt number, and in the Reynolds numbers in the turbulent flow regime, they have the most significant reduction in the friction coefficient.

In this essay, the impact of magnetism amplitude on two-dimensional squeezing nanoparticle stream betwixt two equidistant sheets is inspected. The novelty of this research the dimensionless values of various fluids, such as Prandtel number and friction coefficient, influence the investigation of the velocity and heat transfer parameters of aluminum oxide nanofluid. Three mathematical techniques—AGM, HPM, and NUM—have been used in these experiments, and the outcomes and graphs have been computed and compared using these techniques. The non-dimensioned differential equations have been solved using three methods: Akbari-Ganji Method, Homotopy Perturbation Method, and Numeric technique. A comparison is then made between the resolutions of the presented strategies with the numeric approach in a separate chart. We arrived at the generalization that as the Prandtl number increases, the temperature and thermal of the nanofluid flow increase and its concentration drops, and as the Nusselt number declines. This was done by examining the results of the numerical model that was used to solve the equations. As S is increased, it is seen that the temperature drops while the concentration rises. The Nusselt number has increased in value following the growth in permeability value. Displacement increases along with the heat transfer coefficient.

Software Defined Wireless Sensor Networks (SDWSN) enable flexibility in Wireless Sensor Network (WSN) environments by defining the controllable functions to WSN nodes by the Software Defined Network (SDN) controller. Due to the rapid evolution of SDWSNs, adverse effects also have occurred in terms of interference, energy consumption, and security issues. Several state-of-the-art works lend their utmost best to the SDWSN environment. However, the complete picture (i.e., relatability and security in SDWSN) poses severe challenges. The state-of-the-art issues is addressed in this research by proposing interference-aware Multi-Tier Scheduling for the SDWSN environment (MTS-SDWSN). First, we perform network construction in which the proposed network is constructed in a 2D hexagonal grid structure to resolve the connectivity issue. Upon constructing the network, the SDWSN nodes are clustered and managed to reduce the energy consumption using the Divide Well To Merge Better (DWTMB) algorithm in which the optimal Cluster Leader (CL) is selected based on adequate constraint. The data from the clustered nodes are sent to the Local Base Station (LBS) via CL in which they are scheduled in multi-tier format to diminish the complexity and interference issues. The first tier involved in scheduling among Cluster Members (CMs) and CL using adequate metrics, whereas the successive tiers (i.e., second and third) involved in scheduling among CLs to LBSs and LBSs to Sink Node (SN) are done using the Non-Cooperative Fuzzy Theory (NCFT) method. Last, the scheduled nodes are routed to appropriate destinations using Secure and Optimal Routing Protocol (SORP). The proposed SORP includes the Alibaba and Forty Thieves (AFT) and Multi Criteria Decision Making (MCDM) algorithms for selecting and ranking the optimal routes. Further, the security of the routes is enabled by adopting trust and Moving Target Defense (MTD) mechanisms. The MTD includes route switching among the SDWSN devices and active switch handling using Cycle Generative Adversarial Networks (CGAN) among the switches. The proposed work is implemented using a NS-3.26 simulation tool, and performance of the proposed model and existing works shows that the proposed work outperforms the existing works. [ABSTRACT FROM AUTHOR]

This research explores the influence of air pressure on the surface roughness of ST-37 steel plates in the sandblasting process. Sandblasting is a common method in industry to enhance material surfaces. This study focuses on the effects of varying air pressure on surface roughness, crucial for achieving the desired quality. ST-37 steel plates, known for their strength and versatility, are used in various applications. The research involves a sandblasting process with different air pressures, analyzing surface roughness and contact area. The results indicate a direct correlation between increased air pressure, surface roughness, and contact area.

One of today's concerns regarding energy storage units is the low rate of storage and release of thermal energy and, as a result, the efficiency loss in these units. Subsequently, different strategies are utilized to solve this concern, such as using phase change materials (PCMs) and nanostructures. The background is the low storage and release rate of thermal energy in energy storage units, which leads to efficiency loss. This issue concerns many applications, including energy storage in buildings, vehicles, and electronic devices. This study aims to investigate the effect of external heat flux (EHF) on the thermal efficiency of a specific heat sink by employing molecular dynamics (MD) simulation. After ensuring the simulated atomic structures are stable, EHF is applied to see how it affects the thermal behaviour of the combination. The obtained results show that by increasing the EHF applied to the prototype, the thermal behaviour of the structure improves. So, with the increase of EHF from 0.1 W/m2 to 0.5 W/m2, the heat flux and thermal conductivity (TC) increase from 212.27 W/m2 to 317.90 W/mK to 286.71 W/m2 and 340.03 W/mK. The findings significantly affect energy storage unit efficiency and can inform future research and development efforts.

In this paper, a brief and applied study is performed for reviewing the application of composite materials in civil engineering structures and presenting the significant results and methods based on recent research (as an appropriate short-cut). Some applied trusses and algorithms, related simulations, bridge analysis, and applied solved problems are presented and analyzed in this article. For example, one of the dangerous and undesired happenings is failure and fracture in the structures, which may occur for the buildings. Therefore, the composite behavior must be accurately investigated for predicting and preventing unpleasant hazards. Thus, the analysis and application of the composites in the structures are essential and require increasing the safety and lifetime as well as suitable for managing the time and costs. Moreover, some highlighted challenges for the use of composites in the future such as considering costs and environment management are presented. Finally, a simulation has been done for simplifying the real problem to simple geometrical engineering system in section 6 (solved problems) which would be useful for engineers and students (researchers).

This study proposes a novel design for a serpentine tube to develop an efficient photovoltaic-thermal (PV/T) system. For this purpose, three different hybrid nanofluids and two types of PCM were numerically investigated in a novel serpentine tube with different cross-sectional shapes (rectangular, circular, and triangular). The electrical, thermal, and exergy efficiencies of the PV/T system are evaluated to ascertain the feasibility of the proposed configuration and working fluid. The results showed that using PCM composite and a rectangular cross-section increased thermal and electrical efficiency by 31.1 % and 5.4 %, respectively, compared to the state without PCM and the circular cross-section.For a more comprehensive assessment, the effect of three hybrid nanofluids with a volume concentration of 1.5 % is studied to determine which nanofluid improves heat transfer. Fe3O4-MWCNT demonstrates the most effective nanofluid for cooling down the PV cell temperature. It is used with a volume concentration of up to 4.5 % to investigate how increasing the concentration of hybrid nanofluid can affect important parameters such as cell temperature, fluid outlet temperature, electrical, and thermal efficiency.Moreover, using Fe3O4-MWCNT (4.5 %) along with PCM and PCM composite increases the exergy efficiency by 13.3 % and 16.2 %.

Nowadays, cardiovascular illnesses are among the leading causes of death in the world. Thus, many studies have been performed to diagnose and prevention of these diseases. Studies show that the computational hemodynamic method (CHD) is a very effective method to control and prevent the progression of this type of disease. In this computational paper, the impression of five non-Newtonian viscosity models (nNVMs) on cerebral blood vessels (CBV) is investigated by CHD. In this simulation, blood flow is supposed steady, laminar, incompressible, and non-Newtonian. The parameters of Nusselt number (Nu), dimensionless temperature (θ), pressure drop (Δp), and dimensionless average wall shear stress (DAWSS) are also investigated by considering the effects of heat generated by the body. Utilizing the FVM and SIMPLE scheme for pressure–velocity coupling is a good approach to investigating CBVs for five different viscosity models. In the results, it is shown that the θ and Δp+ increase with increasing Reynolds number (Re) in the CBVs. By enhancing the Re from 90 to 120 in the Cross viscosity model, the Δp+ changes about 1.391 times. The DAWSS grows by increasing the Re in all viscosity models. This increase in DAWSS leads to an increasing velocity gradient close to the cerebral vessel wall.

Aerogels are formed from a lattice of interconnected nanoparticles with a nanometer space between them. These nanostructured materials, with very low density and high specific surfaces, show exceptional properties, so their applications in various fields are expanding. In the present study, the mechanical behavior of paraffin-reinforced silica aerogel was examined by the change in the stress-strain curve, ultimate strength (US), and Young's modulus (YM) at different initial temperatures of 300, 310, 320, 330, and 350 K by MD and LAMMPS. It is revealed that rising the initial temperature can affect the silica aerogel's mechanical properties and impair the structure's mechanical strength. By increasing the initial temperature from 300 to 350 K, the US and YM modules declined from 410.45 to 1073.13 to 351.36–661.4 MPa, respectively. Physically, this mechanical performance results from increased atomic oscillations inside the computational box. Therefore, it is concluded that the effect of temperature on silica's mechanical performance is important and used in various industries.

This essay focuses on studying the nonlinear fractional integral equation. Various methods, including Akbari-Ganji's Method (AGM), Homotopy Perturbation Method (HPM), and Vibrational Iteration Method (VIM), are utilized to obtain its solution. We introduce an innovative approach to obtain rough approximations for fractional differential equations. These equations play a significant role in the field of fluid dynamics and find widespread application. In this article, we have used analytical methods to check the correctness of the answers. Maple mathematical software is used to solve all fractional equations. Ordinary equations and fractional differential equations have connections to entropy, wavelets, and other related concepts. To demonstrate the method, a few examples are employed, chosen for their accuracy and simplicity of implementation. The solutions are explained using convergent series. According to the calculations performed with analytical methods on the fractional integral equations of the nonlinear oscillator, Due to the swing movements of the oscillator, as the swing movement's increase, the velocity gradient becomes an upward trend.

The issue of stability controlling cutting slopes is particularly important in clay-shale slopes, a typical expanding sedimentary layer with poor engineering geological conditions and mechanical characteristics. Therefore, research on the causes of failure and remedies for clay-shale cutting slopes is required to serve as an overview for handling and preserving clay-shale slopes in identical conditions. However, the trusted information about the need for further related clay shale research and clay shale in slope stability has yet to be specifically presented. This review study summarizes the published research for clay shale beginning in 1980, presents a bibliometric analysis to examine the published research based on year and country, and provides various study trends in cluster diagram using the VOSviewer program. The analysis also summarized some key goals, effective methodology, and significant findings from the most recent studies to extract information from them that would benefit future research. In conclusion, the results show the need for developing research to fill the knowledge gap regarding clay shale, landslide, and clay mineralogy. In addition, the clay shale slope analysis has revealed the need for additional research into dynamic force and its deformation.

This paper explores how the temperature and velocity change in a specific direction and the rotational velocity when nanofluids flow through triangular, rectangular, and chamfer baffles. The novelty of this article is to study and investigate the thermal and fluidic parameters of the velocity gradient and heat transferred between aluminum oxide and SWCNT nanofluids on the tensile surface. This study aims to increase the heat transfer coefficient by installing blades with different shapes. The Finite Element Method is chosen to solve the main equations. This paper utilized the RSM method to optimize the velocity of nanofluid and heat transfer as it passes through the stretching sheet. The main goal of this study mentioned in the article is to explore the impact of various vane shapes installed on the outer surface of a stretched sheet. To summarize, after analyzing the flow of SWCNT and Al2O3 nanofluids on various baffles and blades, it was found that the temperature of SWCNT nanofluid around the baffles was higher compared to the temperature of Al2O3 nanofluids. According to the results from the graphs of how fast something is turning and the factors that transfer heat in the software called Design-Expert, the best improvement happened when the velocity and temperature of the small particles in the liquid were at u = 1.12, and T = 20.18 and the turning velocity was N = 137.29.

Heat pipes are a practical and powerful tool for recovering thermal energy and conserving energy sources. Thermosiphon is one of the most widely used devices that can transfer large amounts of heat at high rates between hot and cold sources without the use of external energy. The amount of vacuum in the pipe, the percentage of fluid filling, the type of operating fluid, the pipe’s length and the quantity of heat flux are the factors affecting the efficiency and effectiveness of the thermosiphon heat pipe. In this paper, the effects of different variables in the construction of heat pipes such as working fluid, pipe length, the use of mesh screen wick structure and the use of internal adiabatic wall on the thermosiphon heat pipes performance are investigated. The results show that using of an internal adiabatic wall eliminates and reduces limitations such as boiling, evaporator drying, thermosiphon flooding and vapor pressure and significantly improves the heat pipe’s performance. So that, the effective thermal conductivity (K) is increased up to 350% using the internal adiabatic wall. However, in some nanofluids, such as water/multi-walled carbon nanotubes (MWCNT), with increasing the nanofluid’s mass fraction, the startup speed in heat pipes with internal adiabatic wall is reduced by up to 20%.

The emergence of significant environmental problems, the depletion of fossil fuel reserves, and the anticipation of price hikes have driven researchers to explore and adopt renewable fuels derived from biological sources. Such renewable energy sources include biomass, biodiesel (BD), ethanol, bioethanol (BE), among others. Biomass is a form of energy that can be obtained from waste or the cultivation of specific plants. Notably, BD fuel can be produced from organic sources, such as animal fats or waste oil from restaurants, which is a considerable advantage of BD. Moreover, BE is a non-toxic, safe, and biodegradable fuel, and ethanol produced biologically is referred to as BE, which represents a renewable fuel with a non-fossil origin. Against this backdrop, the upcoming research employs two types of alcoholic fuel, ethanol and BD, as biomass structures. Using molecular dynamics (MD) simulation, the study evaluated the effects of temperature (Temp), pressure (Press), and external heat flux (EHF) on thermal parameters, such as HF and thermal conductivity (TC). The evaluation results indicated that an increase in the initial temperature from 1800 to 2000 K led to higher mobility of the samples, resulting in an increase in the values of HF and TC from 488 to 551 W/m2 and 0.26–0.32 W/m.K, respectively. Similarly, raising the initial Press from 1 to 5 bar increased the number of oscillations and mobility of the structures, leading to increased HF and TC values from 488 to 551 W/m2 and 0.26–0.32 W/m.K, respectively. Notably, the EHF changes exhibited similar behavior. Additionally, a significant outcome was observed when the EHF rose from 1 to 5 W/m2. This increase in EHF led to a corresponding rise in the number of reactions occurring in the studied structure. As a result, the released heat intensified, leading to increased HF and TC values. Specifically, HF values rose from 503 to 538 W/m2, and TC increases from 0.28 to 0.31 W/m.K.