Abstract: Collapsible soils are soils susceptible to large volumetric strains when they become saturated. Numerous soil types fall in the general category of collapsible soils, including gypseous soil which is characterized by relatively low density, appreciable strength and stiffness in the dry state, but is susceptible to significant deformations as a result of wetting. The aim of this study is to investigate the effectiveness of curing period time of carbonation on magnesium oxide stabilization of gypseous soil. In this research, magnesium oxide is used to improve a collapsible gypseous soil by using (0, 5, 10 and 15%) with two relative densities (35 and 75%) and carbonation at different carbonation periods (0, 1, 3 and 24 hours). Conventional collapse tests, single oedometer and double odeometer and modified collapse test are used in this research to investigate the effect of carbonation periods on the improvement of the soil. The modified collapse test apparatus is used. The results illustrated that the collapse potential decreased more than 65% and 55% for the carbonated soil without treatment for conventional tests and modified collapse test, respectively. A decreased about 55% for treated soil with 10% magnesium oxide and carbonated for 3 hours for both of conventional tests and modified collapse test. The carbonation period time is used to accelerate the improvement of the soil as well as decreased the collapse potential and the results showed that no clear change in collapse potential for the period time more than 3 hours.

Abstract: Poor economic growth due to Covid-19 pandemic in the last two years has resulted in a decline in indicators of public welfare. The construction industry sector also experienced a severe decline in productivity;thus, adjustments had to be made to survive the crisis situation. In addition, environmental problems due to development activities also threaten the lives and incomes of people who depend on natural products. These conditions encourage the escalation of interests that affect infrastructure projects in Indonesia. This study aimed to predict the influence of project and affected local community's interests on infrastructure projects social conflicts. Data were obtained by questionnaire from 68 project managers as respondents and analyzed using PLS-SEM. The findings of this study are that the influence of affected community is more dominant than that of project interests on project social conflicts. This shows the important role of communities in the concept of sustainable development with environmental and social perspectives. The results of this study will be useful in drafting the concept of an integrated and standardized environmental and social safeguard framework. To achieve an appropriate framework, further research is needed to examine the framework concept as a moderation of the relationship between interests and project social conflicts. © 2022 Materials and Energy Research Center. All rights reserved.

Abstract: This work is dedicated to survey the structural reinforced concrete's behavior horizontally curved box beams with and without opening. Seven horizontally circular box beams were examined in the experimental work, one without opening, three with vertical opening and three with transverse opening. The test program includes the main variables; direction of opening, location of opening through profile of curved beams (effect of combination of internal forces). The beams were tested as a continuous beam with two spans, each span represents a quarter circle and under the action of two point loads each load located at top face of midspan of beam. The findings indicate that the ultimate load capacity was decreased for all specimens (CB2.V37, CB3.V60, CB4.V82, CB5.T37, CB6.T60 and CB7.T82) by about (5, 11.5, 1.5,1.5, 46.4 and 18.66%) respectively, compared to the control CB1. When compared with the control specimen CB1, all specimens were indicating an increase in Service deformations in terms of deflection and twisting angle at midspan of the circular beams. The ductility was deteriorated for all specimens with opening (CB2.V37, CB3.V60, CB4.V82, CB5.T37, CB6.T60 and CB7.T82), as a percent was about (13.88, 15.3, 19.62, 0.5, 0.5 and 13.88%) respectively, compared with that of control specimen CB1. As a result, generally, a clear degradation with different percentages in overall structural behavior of box beams horizontally curved containing opening according to the location and direction of openings, in this study the transverse openings at 60°, where the opening under the combined maximum (shear and torsion) was led to a catastrophic decrease in the structural performance of horizontally curved box beam.

Abstract: This research looks at how photovoltaic (PV) cells generate energy in different weather conditions. Photovoltaic power today plays a key role in the production of energy and satisfying the needs of consumers all over the world. The PV cell's ability to generate electricity was entirely dependent on sunshine and temperature fluctuations in the environment. Several researchers are working on a variety of MPPT methods for a photovoltaic system. Outdated MPPT techniques are unable to withstand a dramatic change in weather conditions. The fundamental purpose of this study is to associate the numerous unadventurous and clever controllers for MPPT of the PV system, such as the PSO, GA, and CNFF. The MATLAB environment was used to create and simulate the recommended intelligent controller for MPPT in the PV system. Furthermore, the aforementioned findings like Voltage, Current and Power with respect to different irradiance and temperature are compared and evaluated. The performance of the above-mentioned topologies has been related to the optimum intelligent controller for the PV system and cncluded that the CFFNN gives better efficiency with minimum time required to extract. doi

Abstract: The expansion of the online food delivery apps (OFDAs) around the globe has accelerated because of the sudden growing cases of the COVID-19 pandemic. OFDAs are quickly expanding in India, providing a huge number of chances for different OFDA platforms and creating a competitive market. There are several criteria and dimensions for OFDAs businesses to explore to keep with the frequently changing competitive market and achieve long-term success. A Pythagorean fuzzy set (PFS) is a powerful tool for dealing with uncertainty. Distance measure of PFS is a hot research topic and has real-life applications in many areas, such as decision making, medical diagnosis, patterns analysis, clustering, etc. The article aims to examine the results of the novel Pythagorean fuzzy distance measure strategy to select the best online app using TOPSIS method to select the best OFDAs. Firstly, all the axioms related to distance measures are proved for the proposed measures. The proposed work uses five distinct alternatives/options and four attributes/criteria in a fuzzy environment to deal with imprecise and conflicting information. The findings indicate that the proposed methodology is a more realistic way to choose the best OFDAs among others. Finally, a sensitivity analysis is used to determine whether the chosen alternative was the best option among the other components and to ensure that the TOPSIS technique results were accurate.

Abstract: In the last few decades, the geopolymer concrete presented an evolution in civil engineering field. The current study aims to produce a low cost steel fiber reinforced geopolymer concrete with an ecceptable tensile properties. The experimental program aims to investigate the tensile behaviour of geopolymer concrete reinforced with steel fiber and made of recycled materials. The primary ingredients of the steel fiber reinforced geopolymer concrete in this study were waste materials. The recycled steel fiber was extracted from tires and chopped into tiny fibers with an average length of 20 mm and an average diameter of 0.7 mm. The geopolymer concrete in this study consisted of coarse aggregate, which was crushed recycled concrete. Also, the fine aggregate was crushed waste glass. In addition to the compressive strength, tensile test procedures such as splitting tensile strength, double punch tensile strength, and flexural tensile strength were all investigated in this study. Recycled steel fiber was compared to a new hooked-end steel fiber and hybrid steel fiber (50% new + 50% recycled) with three different volumetric percentages of steel fiber (0.5%, 1.0%, and 1.5%). The new steel fiber geopolymer concrete mix with 1.5% of steel fiber showed the highest test results among other mixes, as the tensile strength was increased by nearly 50% in the case of the double punch test. This conduct could be explained as the new steel fiber having a uniform, straight shape with hooked ends, increasing the anchorage between the fly ash binder and the steel fiber. In addition, the recycled steel fiber was contained some rubber crumbs that could be another reason that negatively affected the tensile properties of the geopolymer concrete.

Abstract: There are several attempts to improve surface characteristics of biomaterials with thick film coatings. In this research, a class of protective coating layers of bi-layered Hydroxyapatite (HA)/Al 2 O 3 -SiO 2 (with 10, 20, 30 %wt SiO 2 ) were deposited on titanium (Ti) surfaces by plasma spray technique. The surface features of the applied coating layers were evaluated in detail to confirm the effectiveness of the technique for further biomedical applications. The results demonstrated that uniform and bi-layered plasma sprayed coatings can be successfully prepared through the optimization of engineering parameters. Also, it was found that the roughness of the bi-layered coatings increases with increasing the number of coating layers. The corrosion behavior of the coated and uncoated samples was comparatively investigated using electrochemical tests. The measured current densities (i corr ) for HA, (HA)/Al 2 O 3 -SiO 2 (with 10, 20, 30 %wt SiO 2 ) were 0.27μA/cm 2 , 0.28 μA/cm 2 , 0.23 μA/cm 2 , 0.79 μA/cm 2 , respectively. According to the results, corrosion resistance of samples with 20% SiO 2 is significantly improved compared to the single-layer HA and bare Ti. The outcomes of FESEM results revealed that porosity and cavities related to evaporation of adhesive PVA and it is confirmed by increasing the percentage of silica to more than 20%, porosity has increased. In conclusion, the proposed coating system showed promising abilities for future biomedical applications. It could be optimized and improved by changing the structural characteristics of the substrate, chemical composition and porosity of the coating layers.

Abstract: Radio refractivity is very crucial in the optimal performance of radio systems and is one of the attributes that affect electromagnetic waves in the troposphere. This study presented a comparison of different variants of recurrent neural networks to predict radio refractivity index. The radio refractivity index is predicted based on forty-one years (1980 to 2020) metrological data obtained from the MERRA-2 data re-analysis database. The refractivity index was computed using International Telecommunication Union (ITU) standard. The correlation refractivity index was categorized into strong, weak and no correlation. Rainfall, relative humidity, and air pressure fall in the first category, the temperature falls in the second category while wind speed falls in the last one. The true future and predicted values of the radio refractivity index are close with GRU performing better than the other two models (LSTM and BiLSTM) which proves the accuracy of the proposed model. In conclusion, the proposed model can establish a radio refractivity status of locations at different times of the season, which is of great importance in the effective design, development, and deployment of radio communication systems.

Abstract: With ever increasing demand of IoT based sensor systems, there is a need to assess the performance of wireless sensor networks especially in indoor environment. In these networks, antenna plays an important role. The performance of onboard antenna of the sensor module with respect to its height and orientation are examined in this paper. Several experiments were carried out mostly in indoor environment by changing orientation and height of the antennas. The performance is assessed on the basis of Received Signal Strength (RSS) and its modelling using linear, logarithmic and rational polynomial regression techniques which will characterize the channel in a particular environment. Out of all the combinations in terms of height of the antennas and their orientation, it is found for a given indoor environment, with transmitting antenna at a medium height facing upwards and receiving antenna with an inclination of 70 0 towards transmitter resulted in better performance with R 2poly value of 86.81% and RMSE of 4dB. Therefore, this combination is suggested for wireless sensor networks in indoor environment for achieving the of cost-effective energy-efficient green IoT. The analysis would be useful for improving the efficiency and coverage of wireless sensor networks.

Abstract: To cope with the strong vibration of a supporting structure excited by external loads under operating conditions, and in order to achieve the purpose of vibration reduction by structural optimization through modal modification, a modal modification method was proposed, through structural vibration theory. Subsequently, the search performance of an improved particle swarm optimization method was analyzed before conducting a case study on the structural optimization. Finally, aiming at the problem of strong vibration of gun mount at the time of firing, a finite element model of the gun mount was constructed and the type and natural frequency of the gun vibration in a free state was analyzed. Meanwhile, taking the thickness, height and width of the stiffening structure of the bracket as the design variables, combined with the improved particle swarm algorithm, an optimized mathematical model was developed with the first-order natural frequency of the gun mount as the objective function. The secondary development of Abaqus finite element software by using Python is used as a tool to calculate the optimization model. By virtue of optimation, thickness, width and height of the stiffening structure are 156.4mm, 453.7mm and 238.9mm at the range of [100,600]mm, [100,700]mm, [100,700]mm, respectively, and the base frequency of the gun mount has been increased by 11.3%. The effect is remarkable. doi: 10.5829/ije.2022.35.04a.14

Abstract: High-velocity oxy fuel (HVOF) sprayed coatings can improve the corrosion resistance of bare ASTM SA213-T22 boiler steel. In this report, we have investigated the NiCrMoFeCoAl-30%SiO 2 and NiCrMoFeCoAl-30%Cr 2 O 3 composite coatings were deposited on bare ASTM SA213-T22 boiler steel for corrosion protection. High-temperature corrosion studies were conducted in a molten salt (Na 2 SO 4 -60%V 2 O 5 ) environment at 700ºC under thermo-cyclic conditions. The as-sprayed composite coatings are characterized for microstructure and mechanical properties. The thermo-gravimetric method was utilized to understand the kinetics of corrosion. Characterization of the corrosion products was examined by using scanning electron microscope (SEM)/ Energy dispersive spectroscopy (EDS) and X-ray diffraction (XRD) techniques. The obtained results suggest both the composite coatings are favorable to corrosion resistance over the bare ASTM SA213-T22 boiler steel. The NiCrMoFeCoAl-30%Cr 2 O 3 composite coating was concluded to present a superior corrosion resistance in the high-temperature corrosion environment because of the uniform distribution of the composite coating matrix and the development of protective protection Cr 2 O 3 in the scale. The molten salt heat-treated chromium oxide containing coating shows good corrosion stability than the silica composite. This could be attributed to the high temperature assisted formation metal chromates, chromites and oxide layers.

Abstract: each process parameter. The effect of each process parameter on the UTS was also investigated and analyzed. The results showed that the optimum condition is 20 𝜇𝑚 , 80 mm/min, and 800 rpm. ANOVA analysis demonstrated that the rotational speed is the most significant parameter. An UTS of 290 MPa is predicted by the model, where the actual value is 297 MPa with an error percentage of 3.5%.

Abstract: To ensure the safe and stable operation of nuclear power (NPP), many non-structural components (NSCs) are actively associated with NPP. Generally, floor response spectrum (FRS) is used to design the NSCs. Nevertheless, it is essential to focus on the mounting position and frequency of NSCs which is normally ignored during the conventional design of NSCs. This paper evaluates the effect of mounting location for NSCs over the same floor in a channel-type auxiliary building. The modal parameter estimation is taken into account to capture the dynamic property of the NPP auxiliary building by the shake table test; which leads to the calibration of the finite element model (FEM). The calibration of FEM was conducted through response surface methodology (RSM) and the calibrated model is verified utilizing modal parameters as well as frequency response spectrum function. Finally, the location sensitivity was investigated by time history analysis (THA) under artificially generated design response spectrum compatible earthquakes and sine sweeps. The result showed that the right choice of location for NSCs can be an important measure to reduce the undesirable responses during earthquakes, which can reduce up to 30% horizontal and 70% vertical zero period acceleration (ZPA) responses in channel- type auxiliary buildings.

Abstract: This investigation aims to study the effect of Fe2O3,Ni nanoparticles as a reinforcement materials on the mechanical properties of unsaturated polyester (UPR) as a matrix to produce a nanocomposite material using a casting route. Various examinations and tests were conducted to define the characteristics of the manufactured nanocomposite, such as Field Emission Scanning Electron Microscopy (FESEM), Energy Dispersive Spectrometry (EDS), and Fourier Transform Infrared Spectrometer (FTIR) analysis. The mechanical tests, including tensile, bending and hardness were performed on samples at the room temperature according to ASTM standards, while the magnetic characteristics were defined by vibrating sample magnetometer (VSM). Fe2O3 nanoparticles were incorporation into unsaturated polyester resin by different weight percentages that vary from 0 wt.% to 20 wt.% and a constant concentration 3 wt.% of Ni nanoparticles. The images of FESEM and EDS evinced the homogeneity of F2O3, Ni nanoparticles into the pure unsaturated polyester resin (UPR). While, the improvement in Young's modulus, tensile strength, bending strength, and hardness was compared with those for the UPR. The improvement was 10.02% in Young’s modulus, 44.08% in tensile strength, 13.55% in bending strength, and strength in hardness. Also, the magnetic properties, such as reidual magnetization (Mr), saturation magnetization (Ms) and coercivity force (Hc) enhanced with increasing the concentration of nanoparticles. The preferred percentage to improve the mechanical properties was found at 15 wt.% of Fe2O3 and then decreased above this concentration, whereas the enhancement in hardness was achieved at 20 wt. % of Fe2O3.

Abstract: In this paper, we will be interested in studying a system consisting of a wind turbine operating at variable wind speed, and a two-feed asynchronous machine (DFIG) connected to the grid by the stator and fed by a transducer at the side of the rotor. The conductors are separately controlled for active and reactive power flow between the stator (DFIG) and the grid. The proposed controllers generate reference voltages for the rotor to ensure that the active and reactive power reaches the required reference values, to ensure effective tracking of the optimum operating point and obtaining the maximum electrical power output. Dynamic analysis of the system is performed under the variable wind speed. This analysis is based on active and reactive energy control. The new work in this paper is to introduce theories of genetic algorithms into the control strategy used in the switching chain of wind turbines, to improve performance and efficiency. Simulation results applied to genetic algorithms give greater efficiency, impressive results, and stability to wind turbine systems compared to classic PI regulators. Then, artificial intelligent controls, such as genetic algorithms control, are applied. . Results obtained, in Matlab/Simulink environment, show the efficiency of this proposed unit.

Abstract: its computational complexity due to the significant reduction in the number of teachable network parameters.

Abstract: Fall is one of the most critical health challenges in the community, which can cause severe injuries and even death. The primary purpose of this study is to develop a deep neural network using wearable sensor data to detect falls. Most datasets in this field suffer from the problem of data imbalance so that the instances belonging to the Fall classes are significantly less than the data of the normal class. This study offers a dynamic sampling technique for increasing the balance rate between the samples belonging to fall and normal classes to improve the accuracy of the learning algorithms. The Sisfall dataset was used in which human activity is divided into three categories: normal activity (BKG), moments before the fall (Alert), and role on the ground (Fall). Three deep learning models, CNN, LSTM, and a hybrid model called Conv-LSTM, were implemented on this dataset, and their performance was evaluated. Accordingly, the Conv-LSTM hybrid model presents 96.23%, 98.59%, and 99.38% in the Sensitivity parameter for the BKG, Alert, and Fall classes, respectively. For the accuracy parameter, we have managed to reach 97.12%. In addition, by using noise smoothing and removal techniques, we can hit a 97.83% accuracy rate. The results indicate the proposed model's superiority compared to other similar studies.

Abstract: In this paper, the normal exergy scrutiny (NES) and advanced exergy scrutiny (AES) of a waste heat recovery (WHR) system was performed. The proposed system contains a dual-loop organic Rankine cycle (DORC) which recovers the available waste heat of the intake air, exhaust gas, and coolant streams of a 12-cylinder heavy-duty stationary diesel engine. A well-known method of the AES called the thermodynamic cycle approach is utilized to determine each component exergy destruction parts namely exogenous/endogenous, unavoidable/avoidable, etc. Results showed that 59.04 kW from the 258.69 kW total exergy destruction rate of the system could be eliminated (22.82% of the total exergy destruction rate). The total avoidable exergy destruction part of the low-temperature loop accounts for 46.62 kW, which indicates that it requires more attention than that of the high-temperature loop by 12.42 kW. Furthermore, it is revealed that to enhance the overall productivity of the system, there is a relatively significant difference in priority order regarding the improvement of system components. The AES has proposed this ranking for improvement priority of components: condenser, expander 2, expander 1, respectively. While the NES has specified the priority as the evaporator 1, condenser, expander 2, respectively.

Abstract: Identification of combined power quality disturbances in the modern power systems by considering the development of different types of loads and distribution generations has become increasingly important. The novelty of this paper comes from the accurate and fast identification of the combined power quality disturbances in the presence of different distributed generations and loads such as photovoltaic cell, wind turbine with doubly fed induction generators, diesel engines, electric arc furnace, DC machine, 6-pulse and 12-pulse rectifier loads. In this paper, the features are extracted using variational mode decomposition, just from voltage waveforms. To reduce the redundant data, dimension of features vector, and time, the Relief-F method and correlation feature selection method are applied on the extracted features and these two methods are compared together. In this paper, the K-nearest neighbors classifier is used to classify the multiple power quality disturbances. To verify the effectiveness of the proposed method, different scenarios such as misfiring, variation of sun radiation and wind speed, entrance and exit of loads, capacitors and distributed generators, different fault at the grid in half-load to full-load were simulated. This method can be used as an added algorithm for smart metering in modern and smart power systems.

Abstract: Every year, many newborns lose their sight to retinopathy of prematurity (ROP) worldwide. Despite its high prevalence and adverse consequences, periodic examinations can effectively prevent it. The use of an intelligent system enables physicians to avoid medical mistakes while examining newborns. The optic disk (OD) is an integral part of the retina for grading the severity and progression of ROP. Due to the uneven brightness and lack of a defined OD border, the use of retinal images of infants is very challenging for OD diagnosis. This paper provides an innovative model of OD segmentation based on attention gate. Initially, the images were collected and preprocessed and inputted into a novel deep convolutional neural network consisting of attention in skip connections. The architecture is comprised of a two-stage convolutional network. Different outputs are obtained from two individual branches of the original image and image features in the first stage. The outputs were concatenated to transfer into the post-processing stage to identify the area related to the OD. The final results based on the Dice coefficient (Dice) and the Intersection-Over-Union (IoU) were 94.22% and 86.1%, respectively.

Abstract: Wireless body area network is an emerging technology that has been able to provide a better experience of mobility and flexibility for humans using tiny and low power sensors inside, outside, or around the body compared to the traditional wired monitoring systems. Due to numerous constraints in size, energy consumption, and security of implant devices in the human body, it is still a significant research challenge to design these systems in a reliable and energy-efficient fashion. To provide quality of service, timely and secure delivery of real-time data needs be done without any loss. This paper attempts to provide a communication protocol in order to upgrade QoS levels in WBANs and reduce energy consumption in sensor nodes. To do so, the EDF real-time scheduling algorithm and its combination with the LLF scheduling algorithm are employed to prioritize sensor nodes for sending data packets. The proposed method could optimize the system performance when it is in the event of an overload and tasks miss their deadlines in a row. The OMNET++ simulation environment is used to evaluate the proposed solution's efficiency which checks packet delivery rate and mean-power consumption evaluation criteria in the sink and sensor nodes. This is done with different numbers of nodes in the network. The results show that the proposed strategy could provide an appropriate improvement in sending and receiving packets for body area networks.

Abstract: This paper presents a reliability analysis of a two-span reinforced concrete beam, taking into account of random variations in cross-sectional dimensions, area and position of reinforcement for sagging and hogging bending moments, material strengths, loads and model uncertainties. In addition, the limit state functions for the statically indeterminate beam were derived; considering the static equilibrium requirement after the moments were redistributed as well as the codified allowable limit for the adjusted moment at each beam section. A large number of Monte Carlo simulations were performed in which the basic variables were modeled with normal, lognormal and Gumbel distributions. When the elastic moment distribution was used in evaluating the beam reliability, the two-span beam behaved as a series system with three critical nodes located at the interior support and midspan sections. The probability that the system had at least one overloaded node was greater than the failure probability of an individual node. However, considering moment redistribution made it possible to reduce the amount of reinforcement whilst maintaining the reliability of the beam. When the reinforcement area was reduced by 26% at the support section or 14% at the midspan sections, the failure probability was predicted to be 6.90  10 -5 , which is deemed acceptable for a 50 year reference period.

Abstract: Recently, the bio-mediated soil improvement techniques have an increasing attention. In this method, the bacteria was cultivated aerobically in the laboratory and added to the soil with reactant solutions such as urea and calcium chloride. Most of the existing studies are on sandy soils and a few researches have done on silty sandy soils. However, most soils in nature are compounds of fine-grained and coarse-grained soils. In fine-grained soils, silt does not have very good resistance due to the lack of adhesion between its particles. Hence, in this study Sporosarcina pasteurii bacterium was aerobically cultivated for stabilizing the sand with different percentages of silt to determine the optimum bacteria suspension volume. After some bacterial tests such as measuring bacterial growth, standard plate count, gram staining, pH determination, growth without urea, and urease test, geo-technical tests like soil sieve, compaction, and Atterberg limits were also done. Standard plate count was estimated 2.5*10 8 through serial dilution plating and culture media pH was determined 8.64 from different samples. Moreover, to achieve the best results, different sampling methods were compared. As the calcium carbonate creates a network of calcified bridges of calcite between sand grains, an electron microscope was used for scanning the surface with a focused beam of electrons. Results of triaxial tests showed that by adding optimum bacteria suspension volume, the maximum strength for samples with 0, 10, 20, 30 and 40% of silt was improved from 700, 900, 750, 600 and550 to 1100, 1400, 1550, 1600, and 1500 kPa, respectively .

Abstract: In order to investigate the effect of fiber volume fraction on the mechanical behavior of ultra-high performance concrete composites (UHPCC), five different volume fractions of macro steel fibers (Vf = 0.5, 1, 1.5, 2 and 2.5%) are used within identical mortar matrix. Ultra-high performance fiber reinforced concrete (UHPFRC) mix was designed to achieve a compressive strength of 155 MPa based on the particle packing method. For 12 series of UHPCC mixes, compressive strength, splitting tensile strength, flexural strength, and modulus of elasticity at 28 days are determined. Test results showed a significant improvement in splitting tensile and flexural strengths of UHPFRC with the addition of steel fibers. The maximum values of compressive, splitting tensile and flexural strengths were 155.39, 17.76, and 32.50 MPa, respectively. Stress-strain behavior of fiber-reinforced concrete composites is studied and elastic modulus values evaluated are in the range of 39.52-47.99 GPa. Empirical expressions are developed based on the test results in terms of fiber volume fraction to predict the 28-day strengths of UHPFRC. Comparing the experimental values of earlier researchers to the ones predicted by empirical equations, the average absolute error (AAE) value obtained is within 5%. The proposed model's predictions are in good agreement with the experimental values. Relationship between compressive and flexure strengths of UHPFRC isdeveloped with R2=0.99 and validated.

Abstract: Effects of two admixtures, calcium carbonate powder (CCP) and micro silica gel (MSG) on self- compacting concrete (SCC) properties, such as workability, compressive strength, and durability are investigated. Results, show that, in some cases, concrete with MSG is unable to provide a stable condition, although flowability is higher. Experimental results indicate that the effect of CCP on sustainability, strength and durability of mixture is remarkable. Combo mix design is introduced to benefit from the positive characteristics of two admixtures. Results of decision making method show that this mix can be considered as a proper sample along with the sample containing the optimal dosage of CCP. Moreover, this method indicates the optimal dosage of CCP is 31.25%, which leads to the best improvement in characteristics of fresh and hardened concrete. In practical engineering, economic analysis demonstrates that using CCP is more cost effective, because is accessible and inexpensive in Iranian market.

Abstract: In this study, the effect of polycaprolactone (PCL) coating on the mechanical strength, cell behavior and cell attachment of the hierarchical meso/macroporous Titania scaffold were investigated. Titania scaffold as the substrate was fabricated through the evaporation-induced self-assembly coupled with the foamy method. Then prepared scaffolds were coated by polycaprolactone solution with three different weight percentages by the dip-coating method. SAXS, WAXRD, SEM, compressive strength, MTT and cell attachment test were applied to characterized the samples. Based on XRD results, as polycaprolactone concentration increased, the intensity of the crystalline polycaprolactone phase increased while the TiO 2 peak intensity decreased due to the covering of mesoporous titania by polycaprolactone. Compressive strength showed that by increasing polycaprolactone percent, the porosity decrease from 89.5 to 73.8 % which caused increasing strength from 0.2 to 0.79 MPa. The SEM results illustrated that by increasing polycaprolactone concentration from 1.2 to 1.5 wt%, the macrospores were filled by polycaprolactone. In this regard, The sample containing 1wt% polycaprolactone was choosen as the selective sample. Also, the MTT test reported a small trace of cytotoxicity in contact with the L929 mouse fibroblast cells. The cell attachment test that was performed by using MG63 cells, showed that the coated samples provided the suitable substrate for cells to attach and also showed cell viability on the surface of the coated substrate. Overall, according to the results, the hierarchical meso/macroporous Titania scaffold coated with 1 wt% polycaprolactone, could have good potential to be used in tissue engineering.

Abstract: Encryption is very important to protect sensitive data, especially images, from any illegal access and infringement. This research is presented to provide an image encryption optimization method for communication based on image security. This method uses the grasshopper optimization algorithm to perform optimal encryption and irregular logical mapping. Initially, this approach creates multiple encrypted images and a chaotic map, in which the session key for the initial conditions of the map depends on a simple suspended image. After that, the encrypted images work as an initial and particles set for optimization through the grasshopper optimization algorithm. The optimized encoded image with the correlation coefficient of the continuous pixels is expressed as a function of proportion. The results from Matlab simulation of the proposed encoding method show that the encrypted images are the same, and the adjacent pixels are highly correlated with other outstanding encoding rows, such as planar histogram entropy and effective pixel rate of change average correction strength.

Abstract: An efficient design of a water supply and wastewater collection system is significantly important to tackle the natural uncertainty of this system and the sustainable development goals in developing countries like Iran. To address the natural uncertainty in the water supply and the challenge of global warming, this design must be robust and this motivates a robust optimization. To consider the sustainability criteria, this design should cover all economic, environmental and social impacts. Hence, this study develops innovative solutions based on recent and traditional metaheuristic algorithms for a robust and sustainable water supply and wastewater collection system. Red deer algorithm (RDA) and Keshtel algorithm (KA) as the recent algorithms, are employed. These recent algorithms are compared with the state-of-the-art methods like genetic algorithm (GA) and particle swarm optimization (PSO). An application of our model and algorithms, is tested on a case study in North Khorasan province. After performing some analyses on the performance of our algorithms and sensitivities on the model, a discussion is provided to conclude managerial insights and findings for practitioners in the applied system.

Abstract: Due to the ease of access to platforms that can be used by forgers to tamper digital documents, providing automatic tools for identifying forged images is now a hot research field in image processing. This paper presents a novel forgery detection algorithm based on variants of Benford's law. In the proposed method, Mean Absolute Deviation (MAD) feature is extracted using traditional Benford's law. Also, generalized Benford's law is used for mantissa distribution feature vector. In addition to Benford's law-based features, other statistical features are used to construct the final feature vector. Finally, support vector machine (SVM) with three different kernel functions is used to classify original and forged images. The method has been tested on two common image datasets (CASIA V1.0 and V2.0). The experimental results show that 0.27% and 0.21% improvements on CASIA V1.0 and CASIA V2.0 datasets were achieved, respectively in detection accuracy by the proposed method in comparison to best state-of-the-art methods. The proposed efficient algorithm has a simple implementation. Moreover, on the basis of Benford’s law rich features are extracted from images so that classification process is efficiently performed by a simple SVM classifier short