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Internet of Things (IoT) and mobile edge computing (MEC) architectures are common in real-time application scenarios for improving the reliability of service responses. Energy conservation (EC) and energy harvesting (EH) are significant concerns in such architectures due to the self-sustainable devices and resource-constraint edge nodes. The density of the users and service requirements are further reasons for energy conservation and the need for energy harvesting in these scenarios. This article proposes decisive task scheduling for energy conservation (DTS-EC). The proposed energy conservation method relies on conditional decision-making through classification disseminations and energy slots for data handling. By classifying the energy requirements and the states of the mobile edge nodes, the allocation and queuing of data are determined, preventing overloaded nodes and dissemination. This process is recurrent for varying time slots, edge nodes, and tasks. The proposed method is found to achieve a high data dissemination rate (8.16%), less energy utilization (10.65%), and reduced latency (11.44%) at different time slots. [ABSTRACT FROM AUTHOR]

The role of any fuel cell is direct electricity-generation using electrochemical reaction. However, wasted heat is an unavoidable side-product of any fuel cell. Thermoelectric is another electricity generator producing electricity directly from a source of heat. Hence, this is a potential opportunity to recover the waste heat of the fuel cell by thermoelectric generator meaning higher overall performance of the system. This research proposes and optimizes a novel hybrid fuel cell and two-stage thermoelectric generator to catch the mentioned goal of the research. In this hybrid-system, the serpentine channels of the fuel-cell are directly in contact with ceramic layer of a two-stage thermoelectric generator. The proposed configuration is investigated using a validated 3D-finite-element-method. A comprehensive parametric analysis is provided to optimize the system. The results reveal a great performance for the suggested two-stage TEG configuration when the high-temperature skutterudites and low-temperature bismuth tellurides are employed in the high-temperature and the low-temperature stage respectively. The overall-output-power enhances 2.73-fold in the optimized configuration. Increasing the overall thickness enhances output power, with a notable 233 % increase, when h t goes from 1 to 4. A remarkable 209 % growth is shown when the number of thermocouples in the low temperature stage increases from 36 to 144. [Display omitted] • A portable hybrid fuel cell and thermoelectric generator is proposed. • A comprehensive parametric analysis/optimization is provided. • The overall output power enhanced 2.73-fold in the optimized configuration. • Proposed hybrid system was found appropriate for waste heat recovery application. [ABSTRACT FROM AUTHOR]

The chaotic systems have extensive applications in various branches of engineering problems such as financial problems, image processing, secure communications, and medical problems, among many others. In most applications, a synchronization needs to be made with another favorite chaotic system, or output trajectories track the desired signal. The dynamics of these systems are complicated, they are very sensitive to the initial conditions, and they exhibit a stochastic unpredictable behavior. In this study, a new robust type-3 fuzzy logic control (T3-FLC) is designed that can be applied for a large case of chaotic systems under faulty actuators and unknown perturbed dynamics. The dynamic uncertainties are estimated by the online learned type-3 fuzzy logic systems (T3-FLSs). The rules of T3-FLS are optimized by the Lyapunov theorem. The actuator nonlinearities are identified by a new method. The effects of approximation error (AE), dynamic perturbations and unknown time-varying control gains are tackled by the designed adaptive compensator. The designed compensator is constructed by online estimation of the upper bound of AE. By several simulations and comparison with the new FLS-based controllers, the better performance of the designed T3-FLC is shown. In addition, the performance of the designed controller is examined in a secure communication system. [ABSTRACT FROM AUTHOR]

This paper utilizes spatial econometric reenactments to examine the geographic effects of different types of environmentally friendly power on corban discharges. The example covers 31 nations in the Asia-Pacific district during the time frame 2000 to 2018. The spatial connection in the model was affirmed by symptomatic testing, and the spatial Durbin model was picked as the last model. Results show that Gross domestic product per capita, receptiveness to business sectors, unfamiliar direct venture, energy force, and urbanization critically affect CO2 emanations. In correlation, just wind and sunlight-based energy have added to a generous abatement in ozone harming substance emanations in nations over the long run. In contrast, hydropower, bioenergy, and geothermal energy discoveries have been irrelevant. A cross-sectional examination worldview delineated that nations with more elevated sunlight-based energy yield have higher CO2 outflows, while nations with lower levels have lower CO2 emanations. The presence of spatial impacts in the model gave off an impression of the negative consequences for homegrown CO2 outflows of Gross domestic product per capita and exchange transparency of adjoining nations. Furthermore, energy power and higher creation of sustainable power in adjoining nations will prompt lower homegrown CO2 outflows. [ABSTRACT FROM AUTHOR]

In this study, the efficacy of adding nanoparticles of MWCNTs to the base fluid of paraffin on the thermal conductivity has been investigated. MWCNTs-paraffin samples were prepared at different mass fractions using two-step method. Due to the dependency of thermal conductivity on temperature, experiments were performed at temperatures of 25, 40, 55 and 70 °C. It was found that at any temperature and nanotubes concentration, the incorporation of nanotubes into the base fluid improves the thermal conductivity. Based on the results, at the temperature of 70 °C, the incorporation of nanotubes with a mass fraction of 5% causes up to 40.6% improvement in thermal conductivity. It can be concluded that at higher temperatures, the addition of nanotubes has more positive effects on the thermal conductivity. Also, the higher the mass fraction of nanotubes, the greater the sensitivity of thermal conductivity to temperature. [ABSTRACT FROM AUTHOR]

In this research, the average Nusselt number in tall and narrow enclosures in the presence of mixed convection of a water-based nanofluid (H2O–Cu–TiO2) is determined and compared. The effect of quantities such as Richardson number of 0.01–100, the volume fractions of 0–2% and geometric shape of the enclosure on average Nusselt number and maximum value of flow function is numerically investigated. The FVM and SIMPLER algorithm are used for resolving the nonlinear equations. According to numerical results, for all the Richardson number and two tall and narrow enclosures, the average Nusselt number rises with growing the nanoparticles volume fractions. Comparison of the tall and narrow enclosures shows that for obtaining the highest heat transfer, by growing the nanoparticles volume fractions under similar conditions, it is better to use tall enclosures for large Richardson number and narrow enclosures for small Richardson number. The highest enhancement of the average Nusselt number with increasing the nanoparticles volume fractions for narrow enclosures was 10.44% at the Ri = 0.01. Whereas in the tall enclosures, the highest increase in the average Nusselt number was 14.51% at Ri = 100. For all the Richardson number and two tall and narrow enclosures, the maximum flow function value of the nanoparticles increases with increasing volume fractions. This increase in small Richardson number is greater than in large Richardson number. [ABSTRACT FROM AUTHOR]

The objective of this research was to evaluate the impact of the morphology of SiC additive on the microstructure development, sintering behavior, hardness, and fracture toughness of TiB 2 -based ceramics. For this purpose, three different samples were produced via the hot-pressing method at 1950 °C under 25 MPa for 120 min. Subsequently, the samples were characterized by XRD, SEM, and optical microscopy. The samples containing SiC particles (SiC p) reached their theoretical densities. XRD results manifested the formation of an in-situ TiC during the hot-pressing. Thermodynamical investigation and SEM fractographs revealed the role of a liquid phase in boosting the sintering behavior of as-sintered ceramics. The SEM images also confirmed the in-situ generation of B 4 C in the specimens doped with SiC whiskers (SiC w). Finally, the most significant Vickers hardness (28.9 GPa) and fracture toughness (6.4 MPa m1/2) was secured for the sample toughened by 30 vol% SiC w , whereas the lowest values, namely a Vickers hardness of 18.1 GPa and a fracture toughness of 5.1 MPa m1/2, were obtained for the composites doped with 30 vol% SiC p , and 15 vol% SiC w + 15 vol% SiC p , respectively. [ABSTRACT FROM AUTHOR]

This investigation intended to assess the influence of SiC morphology on the sinterability and physical-mechanical features of TiB 2 -SiC composites. For this aim, different volume percentages of SiC particles and SiC whiskers were introduced to TiB 2 samples hot-pressed at 1950 °C for 2 h under an external pressure of 25 MPa. The characterization of as-sintered specimens was carried out using X-ray diffraction, optical microscopy, and scanning electron microscopy. The relative density studies revealed that SiC w had a more significant impact on the sinterability of TiB 2 -based composites. The XRD investigation confirmed the production of an in-situ TiC phase during the hot-pressing; however, some peaks related to the graphitized carbon also appeared in the patterns of SiC w -doped ceramics. The addition of 25 vol% SiC p halved the average grain size of TiB 2 while introducing the same content of SiC w decreased this value by just around 20%. Finally, the highest Vickers hardness and fracture toughness were obtained for the sample reinforced with 25 vol% SiC w , standing at 29.3 GPa and 6.1 MPa m1/2, respectively. [ABSTRACT FROM AUTHOR]

One of the most studied topics in analytical chemistry and physics is to develop bio-sensors. Aptamers are small single-stranded RNA or DNA oligonucleotides (5–25 kDa), which have advantages in comparison to their antibodies such as physicochemical stability and high binding specificity. They are able to integrate with proteins or small molecules, including intact viral particles, plant lectins, gene-regulation factor, growth factors, antibodies and enzymes. The aptamers have reportedly shown some unique characteristics, including long shelf-life, simple modification to provide covalent bonds to material surfaces, minor batch variation, cost-effectiveness and slight denaturation susceptibility. These features led important efforts toward the development of aptamer-based sensors, known as apta-sensors classified into optical, electrical and mass-sensitive based on the signal transduction mode. This review provided a number of current advancements in selecting, development criteria, and aptamers application with the focus on the effect of apta-sensors, specifically for disease-associated analyses. The review concentrated on the current reports of apta-sensors that are used for evaluating different food and environmental pollutants. [ABSTRACT FROM AUTHOR]

• Effects of magnetic field on heat transfer and entropy generation. • Inclined cavity with Straight, Inclined and Curved Blades containing nanofluid. • Solving nonlinear governing equations by finite volume method and SIMPLE algorithm. • Four different nano powders shapes, namely platelets, cylinders, Fins, and bricks. • The average Nusselt number and entropy generation are decreased by adding different nano powders. Nanopowder shapes are highly effective in nanofluids properties. This study was a numerical analysis of the effect of nanopowder morphology on the natural convection and irreversibilities of water/alumina nanofluids. To this end, a square enclosure was used with constant cold (T c) and hot (T h) temperatures at its right and left walls, respectively. The horizontal surfaces were isolated and the enclosure was exposed to a magnetic field. Two Fins were located on the left wall sharing the same temperature as the wall. The control volume method was used to derive the algebraic form of the equations, and a SIMPLE algorithm written in Fortran was used for the simulations. To investigate the effect of nanopowder shapes, four different shapes, namely platelets, cylinders, blades, and bricks, were used. For a better comparison, nanofluids with different morphologies were compared with a Brownian motion-incorporated model. The results showed that this model predicts the highest heat transfer rate and entropy generation. As its most important result, this paper concluded that free heat convection in nanofluids is not necessarily increased by addition of nanopowder, and in some cases, the Nu number and irreversibilities can be decreased because of the significant increase in nanofluid viscosity. It was also observed that the Nu rises with Ra and falls with the magnetic field intensity. Generally speaking, the greatest and lowest heat transfer coefficients were obtained using the Angled and straight Fins, respectively. [ABSTRACT FROM AUTHOR]

In this work, NiAl-WC composite was synthesized by a mechanical activated thermal explosion process from the powder mixture of nickel, tungsten, aluminum, and graphite. The phase, morphology, and microstructure development during milling and after the thermal explosion process were evaluated by XRD, FE-SEM, and TEM-EDS analysis techniques, respectively. The results indicated that after the thermal explosion of an as-mixed powder mixture, unreacted starting powder remained, and some new phases like Al 0.42 Ni 0.52 and W 2 C formed, which confirmed that the synthesis reactions were not completed. But, the final product of 5 h milled powder after the thermal explosion consisted of desired phases, NiAl and WC. XRD results of 5 h milled powder showed that the mechanical activation had two effects on NiAl-WC composite synthesis, reduction of crystallite and particle size, and better mixing of reactant powders and formation of W 2 C phase as an intermediate phase. These effects increased kinetics of reactions, and finally, NiAl-WC composite formed. [ABSTRACT FROM AUTHOR]

Abstract Financial paper is a note without reason debt or consideration acceptance, issued for obtaining money financing. Financial paper identification system is a hot issue of the current file analysis and identification system, it covers paper classification, image processing, character segmentation and identification, file image compression and other series of processes. A research on multiple aspects of financial paper identification system is made in this paper. On which basis, a financial paper identification system with applied value is established. Through substantive experimental test and practical application, the method has better classification performance and higher processing efficiency, and has been used in bank bill identification processing system in a large scale. [ABSTRACT FROM AUTHOR]

In view of the limited budget of governmental finance and high demands on health and hygiene resources, government needs to study the decision-making issues concerned about the prior allocation behavior of governmental hygiene resources under the circumstance of co-existing disease risk and medical treatment risk in the supply side reform of medical health field. In this paper, the risk preference conditions of social planner for co-existing disease risk and treatment risk having influence on the hygiene allocation of the higher risk group were provided. When both risks are co-existing, the preference conditions of social planner under the single risk are ineffective for him/her for allocating more hygiene resources. The joint effect of the two types of risks is uncertain; however it can be eliminated by applying new risk preference conditions. This paper focuses on researching the hygiene resource allocation sorting risk source under an uncertain condition and finding the important role of the correlation between two risks for the governmental decision on hygiene resource allocation, they will have important significance for deeply pushing the supply side reform of medical health field, improving medical health supply structure and improving public health. [ABSTRACT FROM AUTHOR]

Change in the risk preference of financial asset will bring a change to the utility function of investor, and thereby cause a change to the investment consumption decision. In financial market, the price of risk asset is usually simulated by the geometry Brown movement. In order to make the price of risky asset closer to the reality, the mean reverting process was used to simulate the drift parameter of risky asset in this paper, which was rightly different from the traditional hypothesis. The research in this paper overcame not only the deficiency in the previous research literatures, but also considered the impacts of the risky asset drift coefficient obeying to the mean reverting process on financial asset investment consumption decision, and furthermore derived the value function and the corresponding financial asset’s optimal investment strategy on the basis of the martingale approach, which has important practical value for investor for realizing the utility maximization. [ABSTRACT FROM AUTHOR]

Background: on the context of current medical health supply side reform, medical industry will focus on three aspects accurately, i.e.: “adjusting structure, reducing costs and replenishing short-slab”, whereas the operation efficiency of medical industry is the important issue attracted the attention of academic circles. Methods: the medical industry is easier to be affected by external uncontrollable factors, for instance public health emergency or change in health policy will affect the service cost of hospital, and thence the operation efficiency of medical industry is researched and evaluated by adopting the stochastic frontier cost model. Results: according to the empirical research, Chinese medical industry achieved higher operation efficiency in the process of medical health supply side reform, it reflects not only the higher medical service and management level of medical institution and, but the matching attribute with their current sale. However several hospitals had lower cost efficiency for their medical services, adopted extensive management and involved in insufficient medical resource utilization. Conclusions: the stochastic frontier cost model measures the efficiency of hospital input and output from multiple angles; it has higher scientific nature and adaptability, and complies with the current medical health supply side reform requirements; moreover it is beneficial to expedite to develop Chinese medical industry, reduce operation cost, improve the operation efficiency of medical industry, and boost the medical health supply side reform to achieve success. [ABSTRACT FROM AUTHOR]

Background: in the context of deeply promoting supply-side structural reform in China, the bio-pharmaceutical industry of China is being boosted from three aspects of “adjusting structure, reducing costs and replenishing short-slab”, and the comprehensive strength assessment of bio-pharmaceutical industry cluster has become the important issue focused by the academic circles. Methods: the comparative analysis was made for the comprehensive strength of China bio-pharmaceutical industry cluster on the basis of grey theory analysis by establishing the assessment indicator system and assessment model complying with the characteristics of Chinese bio-pharmaceutical industry. Results: the empirical study revealed that: the comprehensive strength of Chinese bio-pharmaceutical industry cluster in the Yangtze River Delta Region was higher than that of the bio-pharmaceutical industry cluster in the Pearl River Delta and the circum-Bohai-Sea, the comprehensive strength of the bio-pharmaceutical industry cluster in the Pearl River Delta was higher than that of the bio-pharmaceutical industry cluster in the circum-Bohai-Sea. Conclusions: the comprehensive strength of Chinese bio-pharmaceutical industry cluster has to improve further; Chinese bio-pharmaceutical industry cluster needs not only to grasp the opportunity of current supply-side reform to further optimize industrial structure, but also needs to focus on the supply-side elements to improve production efficiency of element and promote its transformation and upgrading. [ABSTRACT FROM AUTHOR]

Space M&A based on industrial concentration and pursuing concentration rent and spillover effect in new normal has become an important method to realize industrial up-grading, and how to evaluate value effect of space M&A with two-stage production system becomes a new project that has yet to be studies in academia. The article builds a M&A value evaluation simulation model based on DEA non-cooperation game to evaluate value effect of space M&A in financial industry in China.it shows, Space M&A with hypotactic game relationship can bring about substantial potential cost saving, and there must be system M&A valid when all subsystems are M&A valid. Optimal input-output index and optimal value index of intermediate variables based on model calculation further helps to obtain the measure of space M&A value improvement, which provides commercial banks with immediate empirical evidences to select M&A under new normal, helps to facilitate optimization of financial resources space configuration, and promotes transformation and upgrading as well as innovative driving of financial industry in China. [ABSTRACT FROM PUBLISHER]

The key to deepening the reform of Chinese economic system is to speed up rural financial reform, strengthen the financial support for new agricultural business entities, and accelerate cultivation and development of new agricultural business entities. The paper, taking pilot area for rural financial reform in Lishui of Zhejiang as the subject of study, makes an in-depth research on an influence of Chinese rural financial reform on cultivation of new agricultural business entities. Empirical research shows, financial support is an important means of cultivating new agricultural business entities, special finances such as governmental universal finance and special finance from financing institutions and funds in the hands of family farms exert an outstanding influence on cultivation of new rural agricultural business entities. Finance supports with different sources play a certain alternative part in cultivation of new agricultural business entities. It is very important for cultivation of new agricultural business entities to strengthen the intensity of rural financial reform and optimize allocation of rural financial resources, which indicates the direction to deepen rural financial reform of China. [ABSTRACT FROM PUBLISHER]

The insulin injection rate in type-I diabetic patients is a complex control problem. The mathematical dynamics for the insulin/glucose metabolism can be different for various patients who undertake different activities, have different lifestyles, and have other illnesses. In this study, a robust regulation system on the basis of generalized type-2 (GT2) fuzzy-logic systems (FLSs) is designed for the regulation of the blood glucose level. Unlike previous studies, the dynamics of glucose–insulin are unknown under high levels of uncertainty. The insulin-glucose metabolism has been identified online by GT2-FLSs, considering the stability criteria. The learning scheme was designed based on the Lyapunov approach. In other words, the GT2-FLSs are learned using adaptation rules that are concluded from the stability theorem. The effect of the dynamic estimation error and other perturbations, such as patient activeness, were eliminated through the designed adaptive fuzzy compensator. The adaptation laws for control parameters, GT2-FLS rule parameters, and the designed compensator were obtained by using the Lyapunov stability theorem. The feasibility and accuracy of the designed control scheme was examined on a modified Bergman model of some patients under different conditions. The simulation results confirm that the suggested controller has excellent performance under various conditions. [ABSTRACT FROM AUTHOR]

Economic efficient Autonomous Road Vehicles (ARVs) are invariably subjected to uncertainties and perturbations. Therefore, control of vehicle systems requires stability to withstand the effect of variations in the nominal performance. Lateral path-tracking is a substantial task of ARVs, especially in critical maneuvering and cornering with variable speed. In this study, a new controller on the basis of interval type-3 (T3) fuzzy logic system (FLSs) is designed. The main novelties and advantages are as follows. (1) The uncertainty is a main challenge in the path-following problem of ARVs. However, in the fuzzy-based approaches, the bounds of uncertainty are assumed to be known. However, in the our suggested approach, the bounds of uncertainties are also fuzzy sets and type-3 FLSs with online adaptation rules are suggested to handle the uncertainties. (2) The approximation errors (AEs) and perturbations are investigated and tackled by the compensators. (3) The bounds of estimation errors are also uncertain and are estimated by the suggested adaptation laws. (4) The stability is ensured under unknown dynamics, perturbations and critical maneuvers. (5) Comparison with the benchmarking techniques and conventional fuzzy approaches verifies that the suggested path-following scheme results in better maneuver performance. [ABSTRACT FROM AUTHOR]

• Optimal geometry for parabolic solar collectors based on energy efficiency. • Nanofluid effect on parabolic solar collectors using two-phase simulation. • Eulerian-Eulerian method is employed to simulate two-phase nanofluid flow. • Energy efficiency for the dual-pass pipe is higher than that of single-pass one. In the present paper, the effect of U-shaped absorber tube on the performance of parabolic solar collector containing two-phase non-Newtonian nanofluids is studied numerically. The present study aims to obtain an optimal geometry for parabolic solar collectors based on energy efficiency. In this study, the effect of using nanofluid on parabolic solar collectors is investigated using two-phase simulation. The effect of Re number (2500

The combined impacts of inclined Lorentz force and thermal radiation on natural convection inside a porous chamber having micropolar nanoliquid and elliptical tilted heater are examined numerically. Micropolar fluid containing nanoparticles of copper oxide of low concentration circulates within the domain affected by the buoyancy and Lorentz forces. KKL approach is applied to define dependency of the nanofluid heat conductivity and viscosity on the nano-sized particles concentration and temperature, simultaneously. Governing equations with relevant boundary conditions written in non-dimensional stream function were solved by the Galerkin finite element method. An impact of important control parameters on micropolar nanofluid flow and heat exchange was analyzed. It was shown that change of the elliptical heater orientation reflects a significant modification of considered isolines and heat exchange rate. At the same time, average Nusselt number has maximum values for α = 0 and α = π and minimum value at α = π/2. [ABSTRACT FROM AUTHOR]

• A critique viewpoint is provided fro effectiveness. • Experiments are carried out to support the said viewpoint. • All possible curve behaviors of effectiveness are described. • Probable previous imperfect effectiveness analysis was mentioned. In this study attempts are made to clarify some hidden features of effectiveness concept (the ratio of actual heat transfer to maximum possible heat transfer) of heat exchangers and provide a critique viewpoint and comprehensive description about that. It is shown in present paper that the effectiveness parameter requires much more attention when it is used in fluid-flow parametric or sensitivity studies of heat exchangers and lack of consideration of its hidden features may lead to incorrect or imperfect decision-makings on curve behavior of effectiveness. Indeed, it is shown that the curve trend of effectiveness against the Reynolds number of one side of heat exchanger can be ascending, descending, or ascending-descending depending on the mass flow rate (Re number) of the other side fluid. Although this critique viewpoint is not considered as a weakness of the effectiveness definition for heat exchangers, inattention may lead to wrong or imperfect inferences in sensitivity analysis of effectiveness parameter. Moreover, it is not logical to provide empirical correlation for effectiveness against flow parameters without the consideration of described features of effectiveness in this study. In order to support the described viewpoint some experiments are performed on double helical tube heat exchanger to evaluate the related thermal parameters and describe the mentioned features of effectiveness statistically. However, the provided analysis is valid for any other type heat exchanger as well. [ABSTRACT FROM AUTHOR]

In this paper, numerical simulation of Water-Copper nanofluid flow in a three-dimensional nanochannel with different types of surface roughness geometry using Molecular dynamics simulation (MDS) is performed. NVT ensemble is used to keep the particle number, volume, and temperature constant in the simulated system. The results show that as the volume fraction of nanoparticles (φ) increases, an increase in the amplitude of the fluctuations was observed. Also, the maximum velocity decreases, but there is no particular change in the amount of slip velocity. Increasing external force as well as reducing the surface roughness somehow increases the mean velocity. • Numerical simulation of Water-Copper nanofluid flow in a three-dimensional Copper nanochannel • Different types of surface roughness geometry • Using molecular dynamics simulation • NVT ensemble is used to keep the particle number, volume, and temperature constant. • Increasing external force increases the mean velocity in the channel. [ABSTRACT FROM AUTHOR]

• A numerical study is done on the blood flow inside an artery with a cone shape of stenosis. • An artery has different stenosis angles. • The finite volume method is employed to determine blood properties. • Different values of parameters of the Sisko model are employed. • Results of this research show the application of mechanical engineering to support medial concerns. In this work, a numerical study is done on the blood flow inside an artery with a cone shape of stenosis. An artery has different stenosis angles. Also, blood flow is energized by constant heat flux which is applied on the wall. The finite volume method is employed to determine blood properties on the basis of a Sisko fluid model with different constant parameters. Firstly, the effects of applying constant heat flux of q'' = 4 W/m2 are studied on the velocity profile of blood flow inside an artery with stenosis angles of φ = 0.5°. Afterward, effects of different stenosis angles of φ = 0.25, φ = 0.5, φ = 0.75, φ = 1 and φ = 1.25 is studied on blood flow temperature profile. Then, different values of the Sisko model are employed to investigate influences of Newtonian and non-Newtonian behaviors of blood fluid on the temperature profiles of blood flow inside an artery with stenosis angle of φ = 0.5°. It is reported that with increasing stenosis angles, blood flow temperature is decreased due to velocity enhancement. This phenomenon is convinced by non-slip condition and sticking non-Newtonian blood fluid to the internal surface of artery wall which reduce velocity from wall surface region to central region of vessel. Also, it is concluded that changing behavior of blood fluid from non-Newtonian to Newtonian behaviors can empower the capability of blood in thermal energy transfer inside human body vessels. Any treatment by balloon angioplasty, percutaneous transluminal angioplasty, and serum injection, which changes the behavior of blood flow inside body veins, can be effective on blood flow temperature. [ABSTRACT FROM AUTHOR]

In this study, the effect of the presence of MWCNTs on the surface tension of paraffin-based fluid was examined. Surface tension measurements of samples containing MWCNTs (0.005–5 wt%) were performed at temperatures of 25–70°C by SITA dynotester. Surface tension corresponds to the adhesive and cohesive forces resultant. Adding nanoparticles diminishes the cohesive force and simultaneously strengthens the adhesive force. Owing to the presence of MWCNTs, the effect of adhesion on the surface tension was superior to the effect of cohesion which consequently diminishes the surface tension. The loading nanoparticles efficacy on surface tension is weekend as the temperature increases. On the other hand, the presence of particles diminishes the sensitivity of surface tension to the temperature growth. In other words, temperature and mass fraction weaken each other's effects. The highest decrease in surface tension is reported to be 18.6%, which occurs at the lowest temperature as well as the maximum mass fraction. The prediction of MWCNTs/liquid paraffin surface tension behavior was performed by applying nonlinear regression and artificial neural network techniques, and statistical calculations revealed that the R-squared for the first and second techniques was calculated to be 0.99 and 0.998, respectively. Both techniques accurately predict nanofluid surface tension. • Suspending MWCNTs in liquid paraffin • Inspection of nanofluid stability using DLS and zeta potential tests • Surface tension measurements of samples by SITA dynotester Measuring surface tension • Presence of MWCNTs diminishes sensitivity of surface tension to temperature growth. • Maximum decrease in surface tension occurred at lowest temperature and highest mass fraction. [ABSTRACT FROM AUTHOR]

One of the famous blue pigments is cobalt aluminate which has a normal spinel that in this work has been synthesized with thermal decomposition technique via the help of olive leaf extract as a precipitation agent. Furthermore, CoAl 2 O 4 /SiO 2 , CoAl 2 O 4 /TiO 2 and CoAl 2 O 4 /graphene nanocomposites were prepared besides the pure one. To investigate the structure and composition of products, X-ray diffraction (XRD) pattern and Fourier transform infrared (FT-IR) analysis were served. Also, the morphologies of products were studied by scanning electron microscopy (SEM) and transmission electron microscopy (TEM) and the effect of different nucleation and growth conditions of the products were investigated. The hydrogen storage ability of the pure CoAl 2 O 4 nanostructures was investigated and to increase the hydrogen storage capacity, different CoAl 2 O 4 nanocomposites were prepared and studied. The maximum discharge capacity and Coulombic efficiencies are 2800 mAh/g and 62% that related toCoAl 2 O 4 /TiO 2 composition and CoAl 2 O 4 , respectively. • The CoAl 2 O 4 spinel was synthesized via olive leaf extract. • Hydrogen storage capacities of CoAl 2 O 4 with its composites were compared. • The Coulombic efficiency of samples was calculated, for the first time. • The discharge capacity increased with the increase of cycle number. • Hydrogen adsorption sites increased by repeating cycles of charge and discharge. [ABSTRACT FROM AUTHOR]

• Non-Newtonian blood flow in the cerebral blood vessels studied. • We used Magnetic Resonance Image to take Digital Imaging. • Impact of Reynolds number, power-law indexes and heat fluxes are investigated. • Pressure drop increase with increasing the Reynolds number and power-law index. • The maximum Nusselt number vessels accrued in the running position of the body. Hemodynamic blood flow analysis in the cerebrovascular is has become one of the important research topics in the bio-mechanic in recent decades. The primary duty of the cerebral blood vessel is supplying Glucose and oxygen for the brain. In this investigation, the non-Newtonian blood flow in the cerebral blood vessels studied. For modeling the geometry of this problem, we used Magnetic Resonance Image (MRI) approach to take Digital Imaging and Communications in Medicine (DICOM) images and using an open-source software package to construct the geometry, which is a complicated one. The power-law indexes, heat flux, and Reynolds number range in the investigation are 0.6 ≤ n ≤ 0.8, 5 ≤ q ≤ 15 Wm −2 and 160 ≤ Re ≤ 310. Effects of Reynolds number, power-law indexes and heat fluxes are investigated. We found that the pressure drop increase with increasing the Reynolds number and power-law index. The maximum Nusselt number in the cerebral blood vessels accrued in the running position of the body in n = 0.8. Also, the highest average wall shear stress occurs in maximum power-law indexes and Reynolds number. By increasing the power-law index and Reynolds number, the wall shear stress increases. [ABSTRACT FROM AUTHOR]

In this study, the effects of adding CuO nanoparticles (NPs) on natural convection heat transfer within an enclosure by considering Brownian motions and thermophoresis were discussed. For this purpose, copper oxide NPs were inserted to water at 1, 3, and 5 vol.%. Using two‐phase model, at constant Grashof (104) and Richardson numbers (102), the enclosure angularity efficacy on the heat transfer was examined at 30°, 45°, and 60°. Adding NPs has one positive effect (thermal conductivity enhancement) and one negative point (viscosity augmentation). It was found that up to 1 vol.%, the addition of NPs improves (due to the superiority of the positive effect on the negative effect) the thermal conductivity but upon 1%, the negative effect is preferred to the positive effect, and hence heat transfer is diminished. At Ri = 100, only adding 1% of the NPs enhanced the Nusselt number (Nu) and adding more NPs diminished the Nu. The angle of the enclosure affects the concentration distribution of the NPs and diminishes eases the NP homogeneity as well. As the enclosure angle augmented from 30° to 60°, the Nu improved by 47%. Note that at the best conditions, adding NPs improved the Nu up to 2%. [ABSTRACT FROM AUTHOR]

In the current paper, the rheological behavior of MWCNTs-TiO 2 /EG hybrid nanofluid was examined. The well-known two-step method was employed to scatter the nano-powder into the ethylene glycol (EG). The dispersed nano-powder consisted of 80 Vol% of TiO 2 and 20 Vol% of MWCNTs. The viscosity measurements were performed at the temperatures ranging from 25 to 55 ° C and various solid volume fractions of 0.05, 0.1, 0.125, 0.25, 0.5, 0.75, and 1%. Experimental results showed that the addition of nano-powder to EG does not alter its Newtonian behavior. Besides, it was found that the viscosity of the prepared sample was directly related to the temperature and solid volume fractions of nano-powder. The dynamic viscosity of samples enhanced by growing the solid nanoparticles volume fraction and decreasing the temperature. The dynamic viscosity increase for the nanofluid containing 1 Vol% of nanoparticles was recorded to be 194% and 323% at the temperatures of 25 and 50 ° C , respectively. Therefore, at greater temperatures, the effect of nanoparticles on the viscosity became more pronounced. Additionally, Adaptive Neuro Fuzzy Inference System (ANFIS) and Support Vector Machine (SVM) methodologies were applied to estimate the nanofluid viscosity. Based on the error calculations, both techniques can forecast the rheological behavior of MWCNTs-TiO2/EG nanofluids with high accuracy. However, the accuracy of the ANFIS method outperforms the SVM approach. • Employing two-step method to disperse the nanoparticles into the ethylene glycol • Adding nanoparticles to ethylene glycol does not alter its Newtonian behavior. • TEM and FESEM were used to assess the nanoparticles surface structure. • At higher temperatures, the effect of nanoparticles on the viscosity became more pronounced. • SVM and ANFIS methodologies were applied to estimate the nanofluid viscosity. [ABSTRACT FROM AUTHOR]

Pumped hydro storages (PHS) are the most common storage in the power system, which covers 99% of the total installed capacity of energy storage facilities in the world. Therefore, optimal offering and bidding strategies of PHS are essential in the energy market. Besides, various uncertainties, especially market price uncertainty is more challenging for PHS operator due to the imposed risks. Therefore, in order to optimally market-participation of these storages, in this paper a novel risk management approach called downside risk constraints (DRC) is applied to get the optimal offering and bidding strategies of the PHS. The DRC method is used along with the stochastic programming to model the risk associated with uncertainty parameter, including electricity market price uncertainty. Hence, ten scenarios are produced using the normal distribution function to model the uncertain parameter. Illustrated examples are determined how to deal with imposed risk from uncertainty by managing financial profit. Finally, according to the obtained results, using the proposed downside risk constraints, PHS operators can experience zero-risk conditions by decreasing their profit by 33% while risk-in-profit is reduced by 100% in versus risk-neutral strategy. • Risk evaluation of pumped hydro storage (PHS) using downside risk constraints. • Obtaining a zero-risk strategy for PHS in the market-participation process. • Providing a zero-risk bidding strategy for buying energy from the market. • Providing a zero-risk offering strategy for selling energy to the market. [ABSTRACT FROM AUTHOR]

This paper presents a molecular dynamics study on the effects of different boundary wall temperatures in the range of 84 K to 133 K on the flow characteristics of Argon fluid flow. An external force of 0.002 eV/Å is enforced on the fluid at the entry of microchannels with roughened and smooth surfaces. Roughness elements are in cubic shape, and fluid atoms are structured inside microchannel in two lateral regions near microchannel walls, while; middle region of the microchannel contains no fluid atom at first. Then, with the passage of computational running, Argon atoms are translocated from two symmetric lateral regions of the microchannel to empty region in the middle segment, under phase change condition. The phase change is prepared by applying different boundary walls temperatures in the order of 84 K, 96 K, 108 K, 114 K, and 133 K. Then, sampling data of density for each case of wall temperatures is done at 4-time steps of 250,000, 500,000,750,000, and 1,000,000. Afterward, the velocity and temperature of Argon fluid flow are reported only at time step 1,000,000. Generally, it is concluded that the roughened surface reduces the intention of Argon atoms to move from lateral layers near the wall to central bins in the middle section of the channel as much as 3% to 5%. Furthermore, adding roughness elements on the smooth surface of microchannel can augmentate density fluctuation. Also, increasing wall temperatures empowers the boiling process, which reduces the effect of roughness. Moreover, roughness can decrease the average velocity of fluid flow values around 1% to 3%. • A statistical investigation • Effects of boundary wall temperatures on the rough and smooth microchannels • Using of molecular dynamic simulation • Increasing wall temperatures empowers boiling process which reduces effect of roughness. [ABSTRACT FROM AUTHOR]

In recent years, renewable energy resources such as wind and solar energy have been considered as the main alternative to fossil fuels due to their benefits such as economic benefits, low environmental pollution, and renewable power generation. The solar chimney is one of these alternatives with a simple structure that can be adopted for generating easy and clean energy. The application of solar chimney in desert areas of the Yazd city with high-intensity solar radiation is efficient and environmentally friendly. Due to the low efficiency of the solar chimney in the night times, a combined configuration has been proposed by considering the solid oxide fuel cell and solid oxide electrolysis cell for storing the surplus energy as Hydrogen for the night times. The paper also presents a developed version of deer hunting optimization algorithm to optimal designing of the economic aspect of the power plant. Simulation results are applied to two different seasons for more analysis and the results of the optimal system are compared with genetic algorithm (GA) and particle swarm optimization algorithm (PSO) to show the system efficiency. The results showed that 0.16 kg/s hydrogen is produced at the peak of the radiation in a district of Yazd city. The results also show the decreasing the loss value based on optimal economical designing gives 1,192,000,000$, 1,190,000,000$, and 8,645,000,000$ cost for the GA and PSO, and the proposed improved deer hunting optimization algorithm, respectively. It also shows that the energy generated by the presented configuration in the summer is higher than the winter. • New configuration is presented for supplying the power and the heat units. • A new improved optimization algorithm is proposed for optimal configuration. • The algorithm is improved version of deer hunting optimization algorithm. • The configuration is designed for a combined solar chimney power plants. • The algorithm is compared with GA and PSO. [ABSTRACT FROM AUTHOR]

There are three major applications (portable, stationary, transportation) of hydrogen energy (HE), and each application play a unique and important role in the sustainable development of energy system. In different regions within a country, different applications of HE are preferred. This paper therefore explores the process to decide the optimal region to develop each of the three subtypes of HE applications. To this end, the Analytical Hierarchy Process (AHP) and a fuzzy Technique the Order of Preference by Similarity to Ideal Solution (TOPSIS) method are used in the present study. Based on a literature review and in-depth interviews with officers, experts, the managers of HE-related enterprises, and consumers, the present study comes up with two selection criteria, namely, the acceptance on the applications of hydrogen energy (i.e., market entry barriers and customer's acceptance), and the integrity of hydrogen energy industrial chain on three applications (i.e., production stage, distribution stage, and marketing stage). This paper uses a case study to explore the functioning of three applications of hydrogen energy in the industrial, cultural and restricted residence regions. Four main findings emerges from this study: (1) the market structure of the portable, stationary and transportation application of HE should be pure competitive, oligopolistic, and monopolistic competition respectively; (2) the customer's acceptance for different applications is different, due to different neighborhood concerns about the quality of life; (3) the cost and benefit of different applications depend on different factors, including government policy, technological improvements and social preferences; (4) in order to promote all HE applications, the process to decide the optimal region to develop a specific HE application depends on the comparative advantages of the application. • Optimal multiple selections process for fostering applications of hydrogen energy were explored. • One of the selection criteria is the acceptance of the applications of hydrogen energy. • The other selection criterion is the integrity of hydrogen energy industrial chain. • The optimal solutions depend on the comparative advantages of different applications and regions. [ABSTRACT FROM AUTHOR]

In this paper, Merton’s typical consumption-saving and investment portfolio selection problem was expanded to the having-time inconformity preference of object, so individual needs to consider to change his/her personal preference when making a decision. By using the simpler method, the HJB equations under different circumstances of limited time and unlimited time were respectively obtained. Besides, the analytical solution of the consumption & investment portfolio selection of the utility function for constant absolute risk aversion was obtained. Compared the study result of Merton with that of this paper, the consumption and wealth were founded to have a linear relationship; however their percentage was not a constant any more, and the percentage of the investment on risky assets was not a constant either, but the total value of the investment on risky assets remained unchanged. Such conclusion has an important guiding significance to the optimization of the cross-period consumption and investment portfolio of investor. [ABSTRACT FROM AUTHOR]

On the basis of pair-copula theory, GARCH model and minimized CVaR approach, the pair-copula-GARCH-GED model was established by the paper to generate the future ROA scenario complying with the historical ROA distribution, and the optimal investment weight of asset portfolio was obtained through the minimized CVaR. In accordance with the empirical analysis, it can be seen that the model could describe the ROA distribution of asset portfolio better, and the one to put the pair-copula approach into the model could bring a more accurate result when analyzing the dependency relationship between multi-dimensional ROAs. The investment portfolio on this basis has better performance on the aspects of stability and profitability. [ABSTRACT FROM AUTHOR]

In this paper a new decision-making method was proposed by relying on the powerful fuzzy information expression ability of Vague set and the practicability of TOPSIS method and grey correlation method on the aspect of multi-attribute decision-making problems. Such new decision-making method based on the integrated TOPSIS method and grey correlation method of Vague set meets not only the decision-making requirements on the accuracy depicted by uncertain fuzzy information and the flexibility of disposal, but also meets the requirements of making comprehensive evaluation on the goodness and badness of decision-making scheme; it represents synchronously the dual-benchmark characteristics of position and shape similarity, and thereby provides a new thinking for the multi-attribute decision-making problems. Lastly, the paper took the selection of target enterprise under merger and acquisition as the analysis basis to describe the effectiveness and feasibility of the decision-making method. [ABSTRACT FROM AUTHOR]

• Using Sisko model, blood flow is simulated inside an artery with cone shape of stenosis. • An artery radius of 0.002 m was fixed to study the effects of stenosis on the flow behavior. • With increasing stenosis angle, maximum blood flow velocity is sharply increased. • Effect of increasing artery radius versus the influences of stenosis angle, is affected by the stress tension. In this work, using Sisko model, blood flow is simulated inside an artery which have cone shape of stenosis with different angles of φ = 0.25, φ = 0.5, φ = 0.75, φ = 1 and φ = 1.25 degree, respectively. In the first step, an artery radius of 0.002 m is fixed to study the effects of cone shape of arterial stenosis on the flow behavior. Then, stenosis angle of φ = 0.5 degree is fixed to study the effects of different Artery radii of 0.002 m, 0.0025 m, 0.003m, and 0.0035 m orderly on the flow behavior. For simulation the blood flow, Sisko model is used. Afterward, stenosis angle of φ = 0.5 degrees with a radius of 0.002m is fixed for investigating the influences of different behavior of blood fluid by manipulation of constant parameters of the Sisko model. It is reported that with increasing arterial stenosis angle, maximum blood flow velocity is sharply increased in central region of artery from 0.12 m/s to 0.16 m/s, 0.25 m/s, 0.36 m/s and 0.56 m/s in order of increasing stenosis angles from φ = 0.25 to φ = 0.5, φ = 0.75, φ = 1 and φ = 1.25 degree, respectively. Also, maximum shear stress of artery wall are as much as 64 Pa, 42 Pa, 24 Pa, 18 Pa and 16Pa respectively in order of stenosis angles of φ = 0.25, φ = 0.5, φ = 0.75, φ = 1 and φ = 1.25 degree. On the other side, the effect of increasing artery radius is against the influences of stenosis angle, and contradiction of these parameters is affected by the stress tension and viscosity of blood. Variations of blood behavior from non-Newtonian to Newtonian shows that shear stress in blood stream in the stenosis artery with non-Newtonian blood is higher than that of Newtonian blood due to differences in their viscous behaviors and reactions in exposure of stenosis and artery wall effects. [ABSTRACT FROM AUTHOR]