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Abstract This study examines the efficacy of employing calcium sulfoaluminate (CSA) cement, an environmentally friendly binder, for enhancing the geomechanical characteristics of sand, particularly under low confining pressure conditions. A series of triaxial consolidated drained tests were performed on sand samples treated with varying content (5, 7, and 10%) of CSA cement and 10% ordinary Portland cement (OPC) under various low confining pressures (50, 100, 200, and 400 kPa). The test findings demonstrated the importance of cement content and confining pressure on the mode of failure, stress–strain and volumetric behavior, failure characteristics, and shear strength parameters of the treated quartz sand. After a curing period of 14 days, samples treated with 10% CSA cement exhibited a remarkable 212% increase in peak deviator stress and an 89% reduction in axial strain at failure, indicating higher initial stiffness compared to untreated samples under a 400 kPa confining pressure. Furthermore, the samples treated with 10% CSA exhibited higher peak deviator stress, initial stiffness, and strength development compared to those treated with 10% OPC. The scanning electron microscopy analysis provides insights into particle breakage and bond degradation processes, which increase with confining pressure in CSA-treated samples. Also, the mode of failure analysis reveals a transition from ductile to slightly brittle behavior with increasing cement content. Notably, the geomechanical properties of the treated material emphasized the significant impact of CSA cement on soil improvement. Thus offering a sustainable alternative for soil improvement in construction projects.

Abstract The issue of rainfall-induced slope failure has attracted more attention from geotechnical engineers as a consequence of global warming. Current cumulative waste disposal has generated scientific interest in the utilization of waste materials in geotechnical design for climate change adaptation measures. Taking into consideration the effect of slope height and angle, steel slag—a waste product derived from the production of steel—was investigated as a slope cover against rainfall. To assess the stability of the slope and the infiltration of water into the soil, numerical analyses were conducted using both SEEP/W and SLOPE/W software in conjunction with rainfall conditions. Based on the findings, it can be concluded that increasing the slope's elevation and inclination will have an adverse effect on its safety factor. Steel slag can nevertheless be utilized for minimizing rainwater infiltration into the slope, as indicated by the pore-water pressure variations and graphs of the safety factor versus time. For a 20-m slope height, steel slag slopes have demonstrated a lower factor of safety difference in comparison to the initial slope without remediation. Regardless of slope angle and slope height, the safety factor reduces marginally during rainfall.

Recent commodity x86 CPUs still dominate the majority of supercomputers and most of them implement vector architectures to support single instruction multiple data (SIMD). Although research on architectural exploration requires computer architecture simulators and a number of simulators have been developed, only a few tools support recent x86 SIMD instructions. This paper describes gem5-AVX, an extended version of the gem5 simulator that enables simulating recent x86 SIMD extensions, especially targeted for high performance computing (HPC). The gem5-AVX comprises advanced vector extension (AVX), AVX2 and subsets of AVX-512, except for cache and memory management instructions. Moreover, it covers full set of streaming SIMD extensions (SSE) and subsequent extensions that are required to simulate HPC workloads. It can simulate the key features of the AVX, AVX2 and AVX-512 such as 256 and 512 bits wide registers, three and four operands syntax, fused multiply-add (FMA), vector gather-scatter using vector scale-index-base (VSIB), mask registers, embedded broadcasting, compressed displacement memory addressing mode. We evaluate the accuracy of gem5-AVX by comparing its results to those of real hardware and Intel’s software development emulator (SDE) running benchmark suites,i.e., high-performance linpack (HPL), high-performance conjugate gradient (HPCG) and NAS parallel benchmark (NPB) which are representative programs in the HPC field. The gem5 and gem5-AVX are compared with the speed-up of HPL benchmark according to configuration combinations. Gem5-AVX, with mean absolute percentage errors of 7.3–9.2% and 9.2–11.9%, is more accurate than gem5, which shows mean absolute percentage errors 17.9–21.5% and 19.7–29.7% for Haswell and Skylake processors, respectively.

Abstract Previous studies have revealed that the contribution of slab reinforcement to the T-beam flexural strength in negative moment regions are not negligible for the seismic capacity design. An effective slab width (i.e., effective width of flanged section) has been proposed, within which the slab reinforcement needs to be included in the calculation of the beam nominal flexural strength in negative moment regions. These studies mainly focused on the cases using normal-strength steel in moment resisting frames. However, recently high-strength steel has been widely used in reinforced concrete moment resisting frames in high seismic regions to avoid congestion near beam-column joints. The use of high-strength steel may affect the beam stiffness due to the fact that it will require less amount of reinforcement, and result in a different normal stress distribution compared to the case with normal-strength steel. Therefore, this paper investigates the slab reinforcement contribution to the flexural strength of the reinforced concrete T-beam designed with high-strength steel in negative moment regions at exterior beam-column joints, for which nonlinear pushover analyses were conducted. Beam reinforcement grade was considered as a primary parameter with several other design variables including slab thickness, height, and span length of the beam. Analytical results show that the use of high-strength steel can result in a wider effective slab width than the case of normal-strength steel for calculating the beam nominal flexural strength under the negative moment. Based on these results, new design equations were proposed.

Designing drilling mud rheology is a complex task, particularly when it comes to preventing filter cakes from obstructing formation pores and making sure they can be easily decomposed using breakers. Incorporating both multiphysics and data-driven numerical simulations into the design of mud rheology experiments creates an additional challenge due to their symmetrical integration. In this computational intelligence study, we introduced numerical validation techniques using 498 available datasets from mud rheology and images from filter cakes. The goal was to symmetrically predict flow, maximize filtration volume, monitor void spaces, and evaluate formation damage occurrences. A neural-objective and image optimization approach to drilling mud rheology automation was employed using an artificial neural network feedforward (ANN-FF) function, a non-ANN-FF function, an image processing tool, and an objective optimization tool. These methods utilized the Google TensorFlow Sequential API-DNN architecture, MATLAB-nftool, the MATLAB-image processing tool, and a single-objective optimization algorithm. However, the analysis emanating from the ANN-FF and non-ANN-FF (with neurons of 10, 12, and 18) indicated that, unlike non-ANN-FF, ANN-FF obtained the highest correlation coefficient of 0.96–0.99. Also, the analysis of SBM and OBM image processing revealed a total void area of 1790 M µm2 and 1739 M µm2, respectively. Both SBM and OBM exhibited notable porosity and permeability that contributed to the enhancement of the flow index. Nonetheless, this study did reveal that the experimental-informed single objective analysis impeded the filtration volume; hence, it demonstrated potential formation damage. It is, therefore, consistent to note that automating flow predictions from mud rheology and filter cakes present an alternative intelligence method for non-programmers to optimize drilling productive time.

Foam flooding by Foam Assisted Water-Alternating-Gas (FAWAG) is an important enhanced oil recovery method that has proven successful in experimental and pilot studies. The present study is carried out to monitor the movement of the foam front once injected into the porous medium. This study aims to investigate applications of resistivity waves to monitor foam propagation in a sandstone formation. In the present lab-scale experiments and simulations, resistivity measurements were carried out to monitor the progression of foam in a sand pack, and the relationships between foam injection time and resistivity, as well as brine saturation, were studied. The brine saturation from foam simulation using CMG STAR is exported to COMSOL and calculated true formation resistivity. A diagram was produced summarizing the progression of foam through the sand pack in the function of time, which enabled us to establish how foam progressed through a porous medium. A surfactant and brine mixture was injected into the sand pack, followed by nitrogen gas to generate the foam in situ. As foam progressed through the sand pack, resistance measurements were taken in three zones of the sand pack. The resistance was then converted into resistivity and finally into brine saturation. As foam travels through the sand pack, it is predicted to displace the brine initially in place. This gradually increases each zone's resistivity (decreases the brine saturation) by displacing the brine. Also, an increase in the surfactant concentration results in higher resistivity. Finally, a comparison of three different surfactant concentrations was evaluated in terms of resistivity results, water saturation, and foam propagation monitoring to obtain the optimum surfactant concentration involved in foam flooding.

Locating petroleum-productive wells using informed geological data, a conventional means, has proven to be tedious and undesirable by reservoir engineers. The former numerical simulator required a lengthy trial-and-error process to manipulate the variables and uncertainties that lie on the reservoir to determine the best placement of the well. Hence, this paper examines the use of a global genetic algorithm (GA) to optimize the placement of wells in complex reservoirs, rather than relying on gradient-based (GB) methods. This is because GB approaches are influenced by the solution’s surface gradient and may only reach local optima, as opposed to global optima. Complex reservoirs have rough surfaces with high uncertainties, which hinders the traditional gradient-based method from converging to global optima. The explicit focus of this study was to examine the impact of various initial well placement distributions, the number of random solution sizes and the crossover rate on cumulative oil production, the optimization of the synthetic reservoir model created by CMG Builder, CMOST, and IMEX indicated that using a greater number of random solutions led to an increase in cumulative oil production. Despite the successful optimization, more generations are required to reach the optimal solution, while the application of GA on our synthetic model has proven efficient for well placement; however, different optimization algorithms such as the improved particle swarm (PSO) and grey wolf optimization (GWO) algorithms could be used to redefine well-placement optimization in CMG.

Using sustainable cement-based alternatives, such as secondary cementitious raw materials (SCMs), could be a viable option to decrease CO2 emissions resulting from cement production. Previously conducted studies to determine the optimal mix designs of concrete primarily focused on either experimental approaches or empirical modeling techniques. However, in these experimental approaches, few tests could be performed for optimization due to time restrictions and lack of resources, and empirical modeling methods cannot be relied on without external validation. The machine learning-based approaches are further characterized by certain shortcomings, including a smaller number of data points, a less robust connection among the controlling factors, and a lack of comparative analyses among machine learning models. Furthermore, the literature on predicting the performance of concrete utilizing binary SCMs (silica fume (SF) and ground granulated blast furnace slag (GGBS)) is not available. Therefore, to address these drawbacks, this research aimed to integrate ML-based models with experimental validations for accurate predictions of the compressive strength (CS) and tensile strength (TS) of concrete that includes SF and GGBS as SCMs. Three soft computing techniques, namely the ANN, ANFIS, and GEP methods, were used for prediction purposes. Eight major input parameters, including the W/B ratio, cement, GGBS, SF, coarse aggregates, fine aggregates, superplasticizer, and the age of the specimens, were considered for modeling. The validity of the established models was assessed by using external experimental validation criteria, statistical metrics, and performance measures. In addition, sensitivity and parametric analyses were performed. Based on statistical measures, the ANFIS models outperformed other models with higher correlation and lower statistical error values. However, the GEP models exhibited superior performance compared to ANFIS and ANN with respect to the closeness of the RMSE, MAE, RSE, and R2 values between the training, validation, and testing sets for both the CS and TS models. Experimental validation showed strong evidence for the applicability of the proposed models with an R2 of 0.88 and error percentages of less than 10%. Sensitivity and parametric investigations demonstrated that the input variables exhibited the patterns described in the experimental dataset and the available literature. Hence, the proposed models are accurate, have better prediction performance, and can be used for design purposes.

Abstract Negative skin friction (NSF) effect on pile foundation design attracts the attention of geotechnical engineers and requires comprehensive research. However, the ways of consideration of NSF for the pile foundation design vary with different design codes. This study aims to compare design code requirements adhering to Construction Codes and Regulations (i.e., SNiP), Eurocode 7 (EC7), Canadian Highway Bridge Design Code (CHBDC), and AASHTO for the pile foundation design subjected to NSF and provide insights for the understanding effect of NSF on the behavior of pile foundation. The overall objective is achieved by designing three cases of a driven pile for given design conditions in Astana city. Then, a sensitivity analysis was performed to estimate the effects of the dimensions of the pile foundation and the shear strength of soils on the bearing resistance. The comparative analysis shows that pile foundation design adhering to CHBDC and AASHTO results in a more conservative strategy than SNiP and EC7 when considering Kazakhstani soil engineering conditions.

Abstract The single-degree-of-freedom nonlinear problem describing the essential dynamics of an oscillating retaining wall based on non-quaking ground and subject to Grob’s swelling pressure is considered. The periodic solutions are derived using harmonic approximation. The amplitude-frequency relation is established by employing Lambert’s special function or alternatively using linearization of the nonlinear force. Analytical results are verified using numerical simulations.

Civil engineering faces a substantial challenge when dealing with soft and compressible clayey soils. Conventional soil stabilization techniques involving ordinary Portland cement (OPC) result in notable CO2 emissions. This study explores the utilization of basic oxygen furnace (BOF) slag, a by-product of steel production, for strengthening kaolin clay. This research investigates the influence of BOF slag particle size, BOF slag content, and the use of activators such as lime and ground granulated blast-furnace slag (GGBFS) on the stabilization of kaolin clay. The strength development is assessed through unconfined compressive strength (UCS) test, bender element (BE) test, and scanning electron microscopy (SEM). The findings reveal that higher BOF content and extended curing periods enhance soil strength, and lime and GGBFS effectively augment the stabilizing properties of BOF slag. Stabilizing kaolin clay with a 30% BOF/GGBFS mixture in a 50/50 ratio with 1% lime and curing for 7 days yielded a compressive strength of 753 kPa, meeting the Federal Highway Administration’s requirement for lime-treated soil. These combined measures contribute to developing a more robust and stable material with enhanced geotechnical properties.

The aim of the research is to evaluate the anti-explosion protecting performance with proper workability of high-performance fiber-reinforced cementitious composites (HPFRCCs) with combined fibers when exposed to live explosives such as those used in warfare and terrorist attacks. Various types of fiber-reinforced cementitious composites with high-energy absorption have been studied and determined resistant to explosions. However, because of difficulty of executing in-field tests using live explosives, the experimental data regarding these types of tests are difficult to be obtained and they are reported insufficiently. The data provided in this research regarding HPFRCC resistance to live explosives, is based on explosion tests conducted to test HPFRCC with various fiber combinations and contents. Binary fibers of long steel and organic fibers achieved desirable anti-explosion protection with synergetic effects from two different fibers with relatively less adverse effects on fundamental performances of fluidity, air content, and compressive strength. This research is expected to contribute on providing the explosion test data for combined fiber HPFRCC under conditions that can assist in providing both a sufficient protection for concrete structures under wide ranged explosions not only military and terrorist attacks, but also industrial accidents, and an enough workability to use with ready-mixed concrete system.

BIM (Building Information Modelling) is used to create and manage data during design, construction, and operation. It helps to effectively manage resources and optimize processes in the construction industry. Geotechnical engineering is one of the complex disciplines that may require BIM integration. Various data types must be provided in a timely manner and require real-time feedback, fast processing, and construction guidance. The first problem presented in the paper is the use of the traditional 2D-based method used by engineers for a particular task. It seems to be impractical when some adjustments are included. Another issue is the lack of communication between the workers. It poses the problem of information exchange and misunderstanding during the interpretation of technical data. This paper aims to find different integration techniques and steps for integrating geotechnical data into the BIM process. Methods used to examine the topic are qualitative research, literature review, and case studies. These methods were useful for studying the problems and introducing the soil information into the BIM application. Firstly, a case study with I-BIM was considered, and the BIM–FEM–BIM interaction was applied to introduce geotechnical information with Plaxis 3D. The results have shown that further development of BIM in infrastructure is needed. Another case study explored the present state of the geotechnical design in BIM and potential solutions. The new frameworks were recreated: many boreholes were imported to the BIM, and a 3D geometric model of the entire hill was created for the hill fortification structure with soil clogging. The last two studies in Malaysia modeled a 3D subsurface and used two geotechnical formats, AGS and CVS. The first includes more information than the second; however, the second can be used for a more generalized model. Overall, BIM–FEM interaction can be used as a geometric model for data transfer. However, the open data format of the Industry Foundation Class (IFC) or geotechnical data format of the AGS and CVS were suggested to be used for greater flexibility. It was also found that excessive information makes the model loaded and complex. Therefore, it was recommended that big data be summarized properly with minimal loss of necessary data. Further research is needed to understand data transmission schemes of geotechnical information better. Moreover, it is recommended to put all the strategies directly into practice to create a geotechnical design.

Southern and southeastern Kazakhstan is a region of intraplate seismicity characterized by several destructive earthquakes. Almaty, the largest metropolis in this region, has many structures with different construction materials and seismic-resistant systems. Among them, residential buildings constructed in the Soviet Union era (before the 1990s) may possess low seismic resisting capacities due to limited seismic design and detailing provisions. Therefore, it is essential to assess seismic risks for these buildings. This paper collected information from a government agency (i.e., KazNIISA), including construction materials, lateral force-resisting systems, and structural ductility capacities for residential buildings constructed in this era. These buildings were then categorized in terms of their seismic vulnerabilities following the European Macro-seismic Scale (EMS-98). Vulnerability curves and probability of damages were developed under different earthquake intensities and peak ground accelerations. The likelihood of varying levels of damage was established for the design basis and maximum considered earthquakes in the Almaty region. It was found that unreinforced masonry and wood buildings tend to be very heavily damaged and even collapse under the maximum considered earthquake. The reinforced and precast concrete buildings have a high probability of heavy to very heavy damage, which may require further analytical assessment since the structure at this damage level will undergo a significant nonlinear response and has a high uncertainty in the seismic performance.

Data-driven models with some evolutionary optimization algorithms, such as particle swarm optimization (PSO) and ant colony optimization (ACO) for hydraulic fracturing of shale reservoirs, have in recent times been validated as one of the best-performing machine learning algorithms. Log data from well-logging tools and physics-driven models is difficult to collate and model to enhance decision-making processes. The study sought to train, test, and validate synthetic data emanating from CMG’s numerically propped fracture morphology modeling to support and enhance productive hydrocarbon production and recovery. This data-driven numerical model was investigated for efficient hydraulic-induced fracturing by using machine learning, gradient descent, and adaptive optimizers. While satiating research curiosities, the online predictive analysis was conducted using the Google TensorFlow tool with the Tensor Processing Unit (TPU), focusing on linear and non-linear neural network regressions. A multi-structured dense layer with 1000, 100, and 1 neurons was compiled with mean absolute error (MAE) as loss functions and evaluation metrics concentrating on stochastic gradient descent (SGD), Adam, and RMSprop optimizers at a learning rate of 0.01. However, the emerging algorithm with the best overall optimization process was found to be Adam, whose error margin was 101.22 and whose accuracy was 80.24% for the entire set of 2000 synthetic data it trained and tested. Based on fracture conductivity, the data indicates that there was a higher chance of hydrocarbon production recovery using this method.

In the common practice of geotechnical design, the state of soil is considered fully saturated, while recent examples show the importance of the consideration of unsaturated conditions as well due to the location of the groundwater table at deeper levels. However, it is problematic to design a foundation and calculate bearing capacity as the internal stress in unsaturated conditions needs to be quantified. The mechanics of unsaturated soils are critical in geotechnical engineering, especially when the case of the foundation design is required. This study aims to investigate the influence of suction on the shaft capacity of pile foundations based on the data obtained from in situ and laboratory testing. The three modified methods (i.e., modified α, β, and λ) were implemented in this study in order to calculate the shaft capacity of the pile foundation incorporating unsaturated soil mechanics principles. In addition, the effect of varying matric suction on shaft capacity was discussed. The results of obtained changes show the importance of rain infiltration in the design of piles in unsaturated conditions. It can be concluded that the most conservative method is found to be the modified β method in designing pile foundations incorporating the suction changes due to rainwater infiltration. However, cost optimization shall be considered while choosing the method for the design. As for the increase in GWT, the modified λ method depicted the most conventional behavior. The possible rain infiltration decreases matric suction, mostly in the upper layers.

Many reclaimed areas in Indonesia have abandoned swampland or idle land which is attributed to various factors. One of the main factors is the unsuitability of the exiting flow system in this area since the condition of the canals and water structures in this area has not been rehabilitated for a long time. No study has been carried out to investigate the suitable model for simulating the appropriate criteria for assessment of erosion within the channel on Tidal lowland in Indonesia. This study focuses on the investigation of erosion occurring within the Rural Channel and Main Drainage Channel on Tidal lowland in Palembang, Indonesia which becomes the originality of this manuscript. The erosion was attributed to the accumulation of sediment transport within the channel of the reclaimed tidal delta region Telang I. The results of the research on the P8-13S scheme show that equilibrium on the accumulation of sediment transport in the channel was observed in the Rural Channel and Main Drainage Channel on average ranging from 3,301,859 m3 to 3,349,103 m3 while the average sedimentation ranged from 809,232–898,467 m3. This study is very important in minimizing the possible erosion near riverbank.

Abstract A renewable energy storage system is being proposed through a multi-disciplinary research project. This system utilizes reinforced concrete pile foundations to store renewable energy generated from solar panels attached to building structures. The renewable energy can be stored in the form of compressed air inside the pile foundation with a hollowed section. The pile foundation should resist complex combined actions including structural loads, soil effects, and pressures induced from the compressed air, and thus it requires a careful analysis and design considerations to secure a sufficient structural safety. This paper presents analytical investigation results on the structural responses of the energy piles under these combined loadings. The pile foundations were designed based on the current design practices for various building geometries including the number of stories and column spacing. The magnitude of air pressure was determined from the thermodynamic cycles for the available renewable energy for storage considering building and pile foundation geometries. Finite element analyses were conducted using an elastic 3D model to determine critical tensile stresses of the pile foundation. These critical tensile stresses were used to identify required reinforcement in the pile section. On this basis, several nonlinear finite element analyses were then conducted using inelastic constitutive models of materials to investigate the crack patterns of the hollowed concrete section. Recommendations were finally presented for proper practical designs of the pile foundation serving as the renewable energy storage medium.

Phase change materials have been applied to a building framework to decrease energy and fossil fuel consumption as well as make the building sector more sustainable. Lightweight structures are attractive and increasingly being used in residential buildings. Hence, in this research, the energy efficiency and thermal performance of buildings located in eight various cities (Helsinki, Kiev, Saint Petersburg, Moscow, Stockholm, Toronto, Montreal, and Kiev) of warm summer humid continental climate (Dfb) were evaluated. The impact of heating and cooling energy savings pattern on the selection of optimum phase change material for each city has been demonstrated. In addition, the impact of volume of PCM, precisely the effect of varying and constant volume, on energy savings was assessed for the lightweight steel-framed building. Simulations were performed in EnergyPlus by applying eleven melting temperature ranges of PCM. Test results demonstrated that energy savings were higher in the swing season and the maximum temperature reduced during these months was 3.3°C. Heating and cooling energy savings were found to strongly influence the selection of optimum PCM. In cities where cooling energy savings were the highest, the optimum PCMs were PCMs 24-26 while in cities where heating energy savings were the highest, the optimum PCM was found to be PCM 21. For constant volume, the performance of optimum PCM raised when the surface area was enlarged, while the thickness of PCM was reduced. Overall, the application of PCM into lightweight steel-framed residential structure located in warm summer humid continental climate region is a feasible option.

Autoclaved aerated concrete (AAC) is commonly used as a modern, energy-efficient construction material in Nur-Sultan, Kazakhstan—the second-coldest national capital in the world after Ulaanbaatar, Mongolia. The autoclave curing method used to manufacture the AAC has potential risks and is environmentally costly because of its high-pressure and -temperature operation. Therefore, for phase I and II studies, non-autoclaved aerated concrete (NAAC) was cast, and its properties were evaluated in terms of compressive strength, density, porosity, and thermal conductivity. Moreover, the thermal conductivity prediction model of NAAC was successfully developed. In this Phase III study, the energy behavior of the NAAC was evaluated by energy simulation for a typical two-story residential house model in Kazakhstan. Different wall materials, such as fired brick and normal concrete, were adapted to compare the energy performance of NAAC. Finally, the annual heat loss and amount of heat transferred through the wall of the house were calculated to cross-check the energy-saving effect of NAAC. It was found that the NAAC conserved energy, because the heating and cooling loads, annual heat loss, and amount of heat transfer of NACC were lower than those of fired brick and normal concrete.

This study explored the dominant discourses on online distance education (ODE) that emerged in South Korean society before, during, and after the COVID-19 pandemic. The authors conducted a topic modeling analysis of 8,865 news articles published by 24 South Korean media outlets between 2019 and 2021. Using the Latent Dirichlet Allocation (LDA) algorithm and social network analysis software (NetMiner), the top five topics and the top ten words associated with each topic were identified from each period. The authors observed significant changes not only in the number of news articles but also in the depth of the conversations published each year. The results have revealed several key points. First, ODE, previously considered marginal and abnormal, gained in normality across all educational levels in Korean society. Second, ODE discourses have been shaped by the unique cultural, historical, and technological infrastructure in South Korea. Third, a clear division between social-justice-oriented and business-oriented ODE discourses reflect a persistent inequality in Korean society. Finally, ODE discourses matured in 2021, with more critical and realistic perspectives on both the positives and negatives of ODE. The useful implications of such insights for post-pandemic ODE research and practice are further discussed.

Data collection is crucial in securing evidence to support students' arguments during scientific inquiries. However, due to the high costs associated with equipping schools with various measurement devices, students are limited in the scope of their scientific inquiry. Arduino can be proposed as a solution to the lack of measurement devices in schools. With Arduino, students can create various measurement devices by connecting different sensors, customize these devices to suit their inquiries, and implement remote sensing using the Internet of Things. However, even when promising new technology serves as a beneficial tool for teaching and learning, its successful integration into the educational system can be challenging if teachers struggle to use it. Technical issues often discourage teachers from incorporating potentially valuable technologies into their classrooms. This article examined the adoption of Arduino in three different cases involving teachers from various educational institutions: a gifted education center, an autonomous club activity in a middle school, and a local community center. We identified four major difficulties: 1) selection of appropriate technologies; 2) credibility issues with information from the Internet; 3) technical complexity due to the intervention of multiple variables; and 4) compliance issues with related acts and regulations. We described each of the technical challenges that teachers faced, in detail, and how they dealt with them. Finally, we discussed suggestions for reducing the barriers to Arduino use for teachers and proposed areas for further research.

This study aims to investigate the thermal performance of PCM and PCM combined with nighttime natural (NV) and mechanical ventilation (MV) applied to a residential building located in eight cities of tropical rainforest climate zone (Af). The analysis was accomplished using numerical simulations and developing a unique methodology for selecting the PCM melting temperature based on the thermal comfort limits. The thermal performance of the PCM integrated building was quantitatively evaluated using the concept of peak temperature drop. Additionally, a novel indicator of Total Temperature Drop (TTD) was introduced to determine the overall impact of the PCM and PCM combined with NV/MV on the thermal comfort conditions inside the building. The results showed that PCM 28 was the most efficient in improving the thermal performance of the building located in the Af climate zone, achieving a TTD of up to 356 °C per year. The usage of PCM 28 combined with nighttime natural ventilation improved the TTD values by up to 15%, whereas the integration of PCM 28 combined with mechanical ventilation resulted in a TTD values increase of up to 45%. Conclusively, mechanical ventilation showed its superiority over natural ventilation in the tropical rainforest climate, and PCM 28 applied together with mechanical ventilation could be used as the optimum combination for the whole climate zone.

The depletion of natural sand resources occurs due to excessive consumption of aggregate for concrete production. Continuous extraction of sand from riverbeds permanently depletes fine aggregate resources. At the same time, a major ecological challenge is the disposal of agricultural waste ash from biomass burning. In this study, an environmental friendly solution is proposed to investigate the incorporation of wheat straw ash (WSA) by replacing 0, 5, 10, 15, and 20% of sand in concrete. Characterization results of WSA revealed that it was well-graded, free from organic impurities, and characterized by perforated and highly porous tubules attributed to its porous morphology. A decrease in fresh concrete density and an increase in slump values were attained by an increase in WSA replacement percentage. An increasing trend in compressive strength, hardened concrete density, and ultrasonic pulse velocity was observed, while a decrease was noticed in the values of water absorption with the increase in WSA replacement percentages and the curing age. The WSA incorporation at all replacement percentages yielded concrete compressive strength values over 21 MPa, which complies with the minimum strength requirement of structural concrete as specified in ACI 318-19. Acid resistance of WSA incorporated concrete improved due to the formation of pozzolanic hydrates as evident in Chappelle activity and thermogravimetric analysis (TGA) results of WSA modified composites. Thus, the incorporation of WSA provides an environmentally friendly solution for its disposal. It helps in conserving natural aggregate resources by providing a suitable alternative to fine aggregate for the construction industry.

The current code specifies a minimum torsional reinforcement ratio to prevent possible brittle failure after torsional cracking in concrete members. However, since there are many researches, in which even the concrete members with the minimum torsional reinforcement fail to secure sufficient reserved strength after torsional cracking, continuous research needs to be carried out. Accordingly, in the authors’ previous research, a minimum torsional reinforcement ratio was proposed based on the reserved strength concept and was extended to the steel fiber-reinforced concrete members in order to suggest the minimum fiber factor as the minimum torsional reinforcement ratio. In the present study, a pure torsion test was carried out on reinforced concrete and steel fiber-reinforced concrete members after a brief introduction on the above, and the proposed model was verified based on the test results. The test results of six torsional specimens were compared with those of the proposed model, and it was found that the proposed model provides a reasonable evaluation on the torsional failure mode of the specimen according to the reserved strength ratio.

Parasitic infections like amebiasis, trichomoniasis, and giardiasis are major health threats in tropical and subtropical regions of the world. Metronidazole (MTZ) is the current drug of choice for amebiasis, giardiasis, and trichomoniasis but it has several adverse effects and potential resistance is a concern. In order to develop alternative antimicrobials, a library of 1H-1,2,3-triazole-tethered metronidazole-isatin conjugates was synthesized using Huisgen's azide-alkyne cycloaddition reaction and evaluated for their amebicidal, anti-trichomonal, and anti-giardial potential. Most of the synthesized conjugates exhibited activities against Trichomonas vaginalis, Tritrichomonas foetus, Entamoeba histolytica, and Giardia lamblia. While activities against T. vaginalis and T. foetus were comparable to that of the standard drug MTZ, better activities were observed against E. histolytica and G. lamblia. Conjugates 9d and 10a were found to be 2–3-folds more potent than MTZ against E. histolytica and 8–16-folds more potent than MTZ against G. lamblia. Further analysis of these compounds on fungi and bacteria did not show inhibitory activity, demonstrating their specific anti-protozoal properties.

The introduction of Eurocode in Kazakhstan allows for the application of modern technological innovations and the elimination of technical barriers for the realization of international projects. It is significant to study the international standards and design requirements provided in Eurocode. This study presents a comparative analysis of Kazakhstani and European approaches for the geotechnical design of foundations and provides the design methods in the considered codes of practice. Three different types of foundations (i.e., raft, pile, and piled raft foundations) were designed following SP RK 5.01-102-2013—Foundations of buildings and structures, SP RK 5.01-103-2013—Pile foundations, and Eurocode 7: Geotechnical design for the Nur-Sultan soil profile. For all three types of foundations, the calculated results of bearing resistance and elastic settlement showed the conservativeness of Eurocode over SNiP-based Kazakhstani building regulations, as the values of bearing resistance and elastic settlement adhering to Kazakhstani code exceeded the Eurocode values. The difference between the obtained results can be explained by the application of higher values of partial safety factors by Eurocode 7. Sensitivity analysis of the bearing resistance on foundation parameters (i.e., raft foundation width and pile length) for the Kazakhstani and European approaches was performed to support the conclusions of the study.

This study aims to examine the scaling and performance of flat sheet aquaporin FO membranes in the presence of calcium salts. Experiments showed that the application of calcium sulphate (CaSO4) resulted in an 8–78% decline in the water flux. An increase in the cross-flow velocity from 3 to 12 cm/s reduced the decline in the flux by 16%. The deposition of salt crystals on the membrane surface led to the alteration in the membrane’s intrinsic properties. Microscopy, attenuated total reflection-Fourier transform infrared (ATR-FTIR) spectroscopy, and X-Ray fluorescence (XRF) analyses confirmed measurements of the zeta potential and contact angle. The use of a three-salt mixture yielded severe scaling as compared with the application of calcium sulphate dehydrate (CaSO4 × 2H2O), i.e., a result of two different crystallisation mechanisms. We found that the amount of sodium chloride (NaCl), saturation index, cross-flow velocity, and flow regime all play an important role in the scaling of aquaporin FO flat sheet membranes.

The design of shallow foundations is performed in accordance with different building regulations depending on geotechnical and geological conditions. This paper involves the design calculations applying Kazakhstani and European approaches. The design of shallow foundations in Nur-Sultan city in Kazakhstan was implemented by the calculation of bearing capacity and elastic settlement in accordance with the design procedures provided in SP RK 5.01-102-2013: Foundations of buildings and structures, and Eurocode 7: Geotechnical design. The calculated results of bearing capacity and elastic settlement for two types of shallow foundations, such as pad foundation and strip foundation, adhering to Kazakhstani and European approaches are relatively comparable. However, the European approach provided higher values of bearing capacity and elastic settlement for the designed shallow foundation compared to the Kazakhstani approach. The difference in the results is explained by the application of different values of partial factors of safety for the determination of bearing capacity and different methods for the calculation of the elastic settlement of shallow foundations (i.e., elasticity theory and layer summation method).

The goal of this study was to investigate the anti-cancer effects of Trans10,cis12 conjugated linoleic acid (t10,c12 CLA). MTT assays and QCM™ chemotaxis 96-wells were used to test the effect of t10,c12 CLA on the proliferation and migration and invasion of cancer cells. qPCR and Western Blotting were used to determine the expression of specific factors. RNA sequencing was conducted using the Illumina platform and apoptosis was measured using a flow cytometry assay. t10,c12 CLA (IC50, 7 μM) inhibited proliferation of ovarian cancer cell lines SKOV-3 and A2780. c9,t11 CLA did not attenuate the proliferation of these cells. Transcription of 165 genes was significantly repressed and 28 genes were elevated. Genes related to ER stress, ATF4, CHOP, and GADD34 were overexpressed whereas EDEM2 and Hsp90, genes required for proteasomal degradation of misfolded proteins, were downregulated upon treatment. While apoptosis was not detected, t10,c12 CLA treatment led to 9-fold increase in autophagolysosomes and higher levels of LC3-II. G1 cell cycle arrest in treated cells was correlated with phosphorylation of GSK3β and loss of β-catenin. microRNA miR184 and miR215 were upregulated. miR184 likely contributed to G1 arrest by downregulating E2F1. miR215 upregulation was correlated with increased expression of p27/Kip-1. t10,c12 CLA-mediated inhibition of invasion and migration correlated with decreased expression of PTP1b and decreased Src activation by inhibiting phosphorylation at Tyr416. Due to its ability to inhibit proliferation and migration, t10,c12 CLA should be considered for treatment of ovarian cancer.

Only thirteen microRNAs are conserved between D. melanogaster and the mouse; however, conditional loss of miRNA function through mutation of Dicer causes defects in proliferation of premeiotic germ cells in both species. This highlights the potentially important, but uncharacterized, role of miRNAs during early spermatogenesis. The goal of this study was to characterize on postnatal day 7, 10, and 14 the content and editing of murine testicular miRNAs, which predominantly arise from spermatogonia and spermatocytes, in contrast to prior descriptions of miRNAs in the adult mouse testis which largely reflects the content of spermatids. Previous studies have shown miRNAs to be abundant in the mouse testis by postnatal day 14; however, through Next Generation Sequencing of testes from a B6;129 background we found abundant earlier expression of miRNAs and describe shifts in the miRNA signature during this period. We detected robust expression of miRNAs encoded on the X chromosome in postnatal day 14 testes, consistent with prior studies showing their resistance to meiotic sex chromosome inactivation. Unexpectedly, we also found a similar positional enrichment for most miRNAs on chromosome 2 at postnatal day 14 and for those on chromosome 12 at postnatal day 7. We quantified in vivo developmental changes in three types of miRNA variation including 5' heterogeneity, editing, and 3' nucleotide addition. We identified eleven putative novel pubertal testis miRNAs whose developmental expression suggests a possible role in early male germ cell development. These studies provide a foundation for interpretation of miRNA changes associated with testicular pathology and identification of novel components of the miRNA editing machinery in the testis.

MicroRNAs (miRNAs) are small non-coding RNAs that mediate post-transcriptional gene silencing. Over 700 human miRNAs have currently been identified, many of which are mutated or de-regulated in diseases. Here we report the identification of novel miRNAs through deep sequencing the small RNAome (