Journal of Applied Engineering Science

EXPERIMENTAL AND NUMERICAL STUDY OF TUNNEL VARIATIONS EFFECTS ON BLAST WAVE TRANSMISSION MECHANISM

Cheng-Wei Hung, Sheng-Jung Pi , Pen-Chou Chen — Mon, 09 Feb 2026 00:00:00 +0100

This study investigates the effects of tunnel configuration changes on blast pressure transmission under near-field explosion conditions using both experimental and numerical approaches. Small-scale models were employed to conduct explosion tests, including near-surface detonations and variations in tunnel patterns. Numerical simulations utilizing ALE (Arbitrary Lagrangian-Eulerian) fluid-structure interaction were performed to evaluate blast pressure transmission. The analysis revealed that elbow-type, T-type, and branched tunnels exhibited varying effects on blast pressure transmission, with significant differences in pressure between the inner and outer walls of the tunnels' bend sections. In elbow-type tunnels, the inner wall experienced greater blast pressure than the outer wall, whereas the opposite was observed in T-type and branched tunnels. The findings demonstrate that the numerical model accurately reflects experimental blast pressure transmission patterns.

PERFORMANCE INVESTIGATION OF SPLIT-WALL AIR CONDITIONING: AN EXPERIMENTAL ANALYSIS OF COP AND EER WITH A CUSTOM DATA LOGGER

Daud Simon Anakottapary, I Gede Artha Negara, Luh Putu Ike Midiani — Mon, 16 Feb 2026 00:00:00 +0100

This investigation presents a comparative performance analysis of inverter and non-inverter air conditioning configurations under tropical climatic conditions, employing a custom-developed data logger system for real-time monitoring. The experimental investigation employed coefficient of performance (COP) and energy efficiency ratio (EER) as primary performance indicators. Both air conditioning configurations were evaluated at a standardized cooling capacity of 2.5 kW to ensure consistent comparative conditions. The experimental setup incorporated a custom-built data logger utilizing an ATmega 2560 microcontroller as the central processing unit, enabling real-time acquisition of thermal and electrical parameters critical for performance evaluation. Comprehensive sensor calibration procedures were conducted to ensure measurement reliability. The DS18B20 temperature sensors underwent rigorous calibration, yielding a mean absolute error (MAE) of ±0.75°C. This result demonstrates a high level of measurement accuracy and complies with established standard calibration acceptance criteria. Quantitative analysis revealed that the inverter system achieved a COP of 4.06, demonstrating 8.6% improvement over the non-inverter system's COP of 3.74. Moreover, the energy efficiency ratio measurements showed the inverter system achieved an EER of 13.8, while the conventional system recorded 12.7, indicating 8.7% improvement. Additionally, the custom data logger demonstrated consistent reliability with multi-parameter measurement capabilities, enabling comprehensive monitoring of essential parameters for HVAC performance.

APPLICATION OF ANALYTIC HIERARCHY PROCESS IN SITE SELECTION OF URBAN CONSOLIDATION CENTERS

Lívia Vass, Tamás Bányai — Thu, 26 Feb 2026 00:00:00 +0100

The Analytic Hierarchy Process (AHP) is a structured and widely-used multi-criteria decision-making (MCDM) method. This study applies AHP to evaluate and rank five potential sites for establishing an Urban Consolidation Center (UCC). UCCs serve as logistics hubs that aggregate deliveries in urban areas, aiming to reduce traffic congestion, emissions, and inefficiencies. The evaluation framework was developed using seven main criteria categories, each containing detailed sub-criteria. A hierarchy was constructed, and pairwise comparisons were conducted to derive weights. The consistency of judgments was verified using the Consistency Ratio (CR). The results yielded a final ranking of the locations, offering a rational and transparent approach to support urban logistics planning.

FLEXURAL PERFORMANCE AND DESIGN EVALUATION OF REINFORCED CONCRETE BEAMS WITH STEEL REINFORCEMENT AND BASALT FIBER-REINFORCED POLYMER LONGITUDINAL BARS

Saif Hallem, Nibras Khalid — Wed, 25 Feb 2026 00:00:00 +0100

This study experimentally and analytically investigates the flexural behaviour of RC beams reinforced with either conventional steel longitudinal bars or basalt fibre-reinforced polymer (BFRP) longitudinal bars in combination with steel stirrups. Eight simply supported beam specimens were tested under monotonic static loading, comprising two distinct reinforcement systems: steel-reinforced control beams and BFRP-reinforced beams. The experimental program evaluated reinforcement and concrete strains, mid-span deflections, cracking behaviour, ultimate load capacity, and elastic energy storage prior to failure. The results indicate that steel-reinforced beams exhibited ductile flexural failure characterized by steel yielding followed by gradual concrete crushing, enabling controlled crack development and deformation. In contrast, beams reinforced with BFRP longitudinal bars failed in a more brittle manner governed by concrete crushing, reflecting the linear-elastic response of BFRP reinforcement, while exhibiting larger deflections and higher concrete strain levels. Despite these differences in failure mode and ductility, BFRP-reinforced beams achieved comparable or higher ultimate load capacities relative to their steel-reinforced counterparts. Analytical predictions based on ACI 440.2R-08 showed good agreement with experimental results, with conservative underestimations of ultimate capacity (ACI/Exp ratios ranging from 0.93 to 0.97), confirming the reliability of current design provisions. The findings highlight the inherent trade-offs between stiffness, ductility, and load-carrying capacity associated with steel and BFRP reinforcement systems and emphasize the importance of serviceability considerations in BFRP-reinforced RC beam design.

CORAL ROCK ASH AS A SUPPLEMENTARY FILLER IN ASPHALT CONCRETE WEARING COURSE: LABORATORY PERFORMANCE AND MECHANISTIC–EMPIRICAL SERVICE-LIFE PREDICTION

Wed, 18 Feb 2026 00:00:00 +0100

Flexible pavements with hot-mix asphalt (HMA) may underperform when conventional mineral filler provides insufficient mastic stiffness and moisture resistance. This study evaluates coral rock ash (CRA) as a partial replacement of conventional mineral filler in an asphalt concrete wearing course (AC–WC) mixture to improve laboratory performance and predicted service life. CRA was introduced at 0–10% of the total mixture mass, replacing an equivalent portion of filler in the gradation. Marshall stability/flow and indirect tensile strength (ITS, tensile strength) were measured at an optimum asphalt content of 6%. To link mixture-scale changes to structural performance, layer responses were computed using KENPAVE multilayer elastic analysis, where the HMA elastic modulus was derived from the ITS-based stiffness correlation used in the study (with Poisson’s ratio held constant), enabling mechanistic–empirical estimation of critical strains and allowable load repetitions. Regression analysis identified 4.8% CRA as optimal, yielding peak Marshall stability (1060.7 kg) and the smallest 7-day strength loss after 60 °C conditioning. Relative to the control, ITS increased by 22.6% (11.62→14.25, unit-consistent with the original dataset). In the mechanistic analysis, the improved mixture stiffness led to a reduction in bottom-HMA tensile strain (εt) and a corresponding increase in predicted allowable repetitions, extending the design life of the reference pavement section from 5 to 7 years. These findings indicate that CRA is a feasible, locally available supplementary filler for improving HMA performance and extending service life in coastal regions, provided that sourcing uses non-living, naturally stranded coral debris and complies with environmental regulations.

DEVELOPMENT OF SIMILARITY CRITERIA FOR PHYSICAL MODELING OF THE PROCESS OF ROADBED COMPACTION

Sun, 15 Feb 2026 00:00:00 +0100

This paper focuses on developing criteria for the physical modeling of roadbed compaction using a vibration roller. A rheological model of the process was employed to establish the relationship between stresses and strains in soils with elastic-viscoplastic properties. Additional similarity criteria were utilized to characterize the design and technological specifications, as well as the initial and boundary conditions of the process. Based on these similarity criteria, a physical model of the working element of a vibration roller was created. A series of experiments was conducted to identify the key parameters of this working element. By analyzing the inverse relationships that define these key design and technological parameters, it is possible to determine optimal values for the essential parameters of the vibration roller.

DEVELOPMENT OF A DEVICE FOR COOLING LADLE LINERS FOR CASTING LADLES

Mon, 02 Feb 2026 00:00:00 +0100

This article focuses on the controlled cooling process of the linings of ferroalloy production ladles. Analysis of the operating conditions of the linings revealed that temperature stresses during heating and cooling are the main cause of damage to the linings of high-temperature units. At the enterprise in question, the cooling process is uncontrolled when the lining is exposed to the workshop atmosphere. This leads to cracks forming in the lining and its subsequent destruction. Cooling schedules have been developed for the ladles under consideration, during which the resulting thermal stresses do not damage the lining. A device has been developed for the ladle liners to ensure the cooling process is kept on schedule. Incomplete liner replacement involves cooling the ladle by supplying a mixture of combustion gases from the ladle heating booth and air. The liner is cooled using a mixture of three media: ambient air from the workshop, combustion products from the ladle heating stand, and combustion products from the ferroalloy gas burnt in the burner. A cooling schedule for casting ladle liners has been developed to ensure that thermal stresses do not exceed the strength limit of the refractory materials. At the same time, the cooling time is reduced from 19 hours 30 minutes to 6 hours 50 minutes. The developed device enables the outer and inner walls of the lining to be cooled, secondary resources (ferroalloy gas and combustion products from the ladle heating stand) to be used.

LQR-BASED ACTIVE SEAT SUSPENSION DESIGN TO IMPROVE BUS DRIVER RIDE COMFORT

Dragan Sekulic — Sun, 01 Feb 2026 00:00:00 +0100

Bus drivers are exposed to vibrations generated by the road surface affecting their fatigue, comfort and health. Vibrations are transmitted from bus wheels to the driver’s body through bus suspension system, bus floor and the seat suspension system. Active and semi-active seat suspensions have been developed to alleviate vibrational negative effects. This paper investigated bus driver ride comfort as a function of bus speeds and road quality considering linear quadratic regulator for active seat suspension system. A 3-degree-of-freedom intercity bus model had been defined for simulation. Bus modelling, controller design and simulations were performed by MATLAB/Simulink software. Results showed that active seat suspension significantly reduces the vertical acceleration transmitted to the driver’s body compared to the passive system. Improvements were particularly noticeable on rough roads and at higher bus speeds.

THERMODYNAMICS ANALYSIS TO EVALUATE THE COMBUSTION PROCESS OF E50 FUEL WITH INJECTION VOLUME VARIATION

Marthen Paloboran, Darmawang, Thomas Pagasis, Thesya Atarezcha Pangruruk — Wed, 21 Jan 2026 00:00:00 +0100

The study is based on the first and second laws of thermodynamics to investigate and analyze the performance of spark ignition engines with varying injection durations of the gasoline and bioethanol fuel blend (E50). Experiments were conducted using standard parameters of engines, including an 11:1 compression ratio and 12 bTDC of ignition timing. The injection volume of the fuel blend was set at 100% to 200% (increment of 25%) of the injection volume of gasoline. The effect of the injection volume of E50 is evident in various performance indicators, including brake-specific fuel consumption (BSFC), thermal efficiency, and brake power, as observed in both energy and exergy analyses. The most important conclusion of this study is that the performance of the engine using E50 would be similar to gasoline (E0), both in energy and exergy analyses, when the injection volume of E50 increased by 25% compared to gasoline.

SIMPLE EQUATION FOR WALL-COLUMN CONTACT LENGTH TO ESTIMATE THE LATERAL STRENGTH OF REINFORCED CONCRETE FRAMES WITH MASONRY INFILL WALLS

Yunus Abdurrasyid, Maidiawati, Jafril Tanjung, Muhammad Ridwan — Thu, 08 Jan 2026 00:00:00 +0100

This work introduces an analytical approach for assessing the seismic capacity of brick masonry infills within reinforced concrete frame structures by the use of a diagonal strut model. The model demonstrates that when the column experiences flexural displacement and the masonry wall endures shear deformation, separation or contact transpires between the masonry infill and the column. The contact height between the masonry infill and column was determined based on the compatibility of lateral displacements of both elements. As a result, a simple equation of contact length between infill and column to determine the lateral strength of masonry infill was employed to calculate the strut width of the masonry infill. The lateral strength for several reinforced concrete frame structures with brick masonry infills was determined using the simplified contact length equation. Furthermore, the analytical results were validated using lateral strength of structure models as outcomes of the pushover method. The results showed that the lateral forces of the structures were relatively similar between the analytical and pushover methods. It suggests that the strut model and the simplified wall-column contact height can be used to estimate the lateral strength of masonry infill in reinforced concrete structures.

EVALUATING AND RANKING SERVICE QUALITY ATTRIBUTES FOR OPTIMIZING METRO RAIL TRANSIT SRVICES IN DHAKA USING ADVANCED ANALYTICS

Mon, 29 Dec 2025 00:00:00 +0100

As Dhaka embraces its first Mass Rapid Transit (MRT) system, understanding what drives users’ satisfaction has become crucial for shaping its success. This study examines the service quality (SQ) of MRT Line-6, identifying and prioritizing the factors that influence user perceptions of this transformative transit solution. Using advanced machine learning models such as Random Forest Classifier, Support Vector Machine, and CART, alongside statistical methods like Probit, Ordered and Multiple Linear Regression, the research provides a robust analysis of twenty-nine (29) SQ indicators. Random Forest Classifier emerged as the most effective model, achieving 88.21% accuracy and offering valuable insights into the interrelationships of key attributes, including inclusive service performance, customer loyalty, switching cost from other transportation mode, ticket affordability, performance of ticketing system, and feeder service costs. Survey results highlight that most users around 60% switched from buses to MRT for its comfort and reliability. The findings emphasize the need to enhance affordability, accessibility, overall comfort and feeder services while promoting digital ticketing through options like Rapid Pass and online platforms. These actionable insights offer a roadmap for policymakers and urban planners to optimize MRT services, aligning with global best practices to support sustainable urban mobility in Dhaka and beyond.

NUMERICAL STUDY OF DROPLET LENGTH AND BREAKUP TIME FOR GEOMETRY AND FLOW PARAMETERS IN A T-JUNCTION MICROFLUIDICS

Sudheer P N, Chandrakantha Bekal, Manjunath Shetty, Satish Shenoy B — Fri, 27 Feb 2026 00:00:00 +0100

Droplet microfluidics finds its application in medical, chemical and biological research as well as in the field of medical device manufacturing. This paper studies the T-junction microfluidics and its parameters, such as droplet length and breakup time, as they vary with the channel width and phase velocities. The study reveals that droplet length rises with an increase in either of the channel width and time taken for breakup reduces and attains a steady value when dispersed phase width is increased. The droplets are smaller in size and form very quickly when the velocity of continuous phase is increased and vice versa. The study can be utilized as a part of a larger study of droplets and their particle encapsulations, and its utilization to generate more efficient and economical medical devices.

VIBRATION PROTECTION OF PUMPS ON THE FOUNDATION WITH A DAMPING PLATE MADE OF ELASTOMER

Fri, 27 Feb 2026 00:00:00 +0100

This paper examines the decrease in pump efficiency under off-design operating conditions, where vibrations and dynamic loads cause bearing failures, overloading of pump–foundation connections, rotor displacement, and runout. These effects also deteriorate the performance of end and slot seals, leading to increased fluid leakage. To address this issue, the use of damping devices in the form of polyurethane elastomer plates is proposed. These materials provide high damping capacity, dynamic modulus of elasticity, tensile strength, and acoustic vibration isolation efficiency. They are also characterized by exceptional abrasion resistance, significantly exceeding that of rubber and low-carbon alloys, as well as resistance to environmental influences, water, oils, and most chemically active substances. The application of elastomer damping deviceАs significantly reduces vibration levels, decreases dynamic loads on foundations, and enhances the overall reliability of pumping equipment.

PARAMETRIC MODELING OF BOLTED ASSEMBLY AND ITS COMPONENTS FOR INDUSTRIAL DESIGN AND APPLICATION

Sylvester Bozherikov — Fri, 27 Feb 2026 00:00:00 +0100

In the present work is proposed a methodology for parametric modeling of a bolted joint including four separate components, each of which is described with tabular dimensions according to current standard. The parametric model can automatically create a bolted assembly unit with a selected fastening size used for creating metal construction and bigger assemblies. Solutions are performed for the bolted joints used mostly in the industry.

COMPREHENSIVE EVALUATION OF INDIAN STANDARD CODES AND CURING APPROACHES FOR GEOPOLYMER CONCRETE

Shweta Tikotkar, Sayali Sandbhor, Sanjay Kulkarni — Mon, 16 Feb 2026 00:00:00 +0100

Geopolymer Concrete (GPC) is a sustainable alternative to Ordinary Portland Cement (OPC), reducing global CO₂ emissions by 8-10% using industrial by-products such as fly ash, slag, metakaolin and silica fume. This approach not only reduces landfill waste and environmental pollution but also aligns with global sustainability goals. Extensive research highlights the increased sustainability of GPC, which includes excellent resistance to chemical corrosion, fire and elevated temperatures, rapid strength development and long-term structural stability. This study undertakes a comprehensive review of the existing literature on GPC, with a special focus on the applicability of Indian Standard (IS) codes for mix design and optimization of curing methods. However, despite significant research progress, GPC remains excluded from building codes in many regions. Given the absence of a dedicated design code for GPC, the review evaluates standardized test protocols for fresh and hard properties tailored to India's climatic conditions. The data for this analysis were systematically extracted from the Scopus database and non-Scopus journals, providing a solid foundation for critical evaluation, presented in a consolidated way to give a clear and focused context. This study validates GPC as a sustainable alternative to conventional concrete in India. However, optimization of mix design parameters, curing methods and durability performance, along with standardized guidelines, is required for widespread adoption. These findings provide important insights for researchers and practitioners to develop environmentally friendly construction technologies.

HYBRID AI-BASED PREDICTIVE QUALITY CONTROL FOR AUTOMOTIVE CUTTING PROCESSES: A SMART MANUFACTURING APPROACH UNDER IATF 16949

Saloua Yahyaoui, Mounia Zaim, Faical Zaim — Sun, 25 Jan 2026 00:00:00 +0100

Ensuring product quality in the automotive industry becomes a technical strategic challenge in the era of digital and networked supply chains. Traditional final inspection methods, often reactive, are not sufficient to attempt the rigorous expectations of IATF 16949. The case of covers seating industry must be at the forefront of industrial excellence. Evoking comfort, functionality, and aesthetics for customer, taking into account that the cutting area in such industry is the focal point to loop considered as internal supplier in the covers supply chain, cutting output is the input for all assembly lines, which means that an uncontrolled quality KPI will disturb the manufacturing process. A hybrid AI –based predictive quality control modeling in cutting process is used combines expert-based validation through the Fuzzy Delphi Method to define the factors affecting the quality of cut products. The integration of data driven prediction (AI and IoT) represented in a linear-regression-based supervised learning model trained and learned with a simulated dataset from real production conditions according to literature review and experts feedback to detect and prevent failures in the early stage of production. The analysis shows the three variates (cutting speed, cutting temperature, vibration intensity) predefined from the literature review were validated as input data. The results indicate a high predictive quality accuracy since the coefficient of determination R² =0.87 and the model statistically very significant ANOVA results. Concluding that the vibration factor have the most significant impact on quality cutting defect. This hybrid AI-based predictive approach provides an improvement lever of the smart automotive manufacturing chains supporting data driven decisions under the IATF 16949.