Proceedings of the 3rd Annual International Conference on Material, Machines and Methods for Sustainable Development (MMMS2022)

Bracing systems are effective secondary structures. They are used commonly to increase the stability of structures, especially steel structures. Many types of braces are used in steel structures such as diagonal bracing, portal bracing, inverted V-bracing, X-bracing, K-bracing, etc. They will make structures to obtain the various buckling behaviors. This paper makes clear the influences of various bracing on the buckling behavior of steel frames. Structures of bracing systems must be paid attention to in steel structural design because structural stability is the one of significant criteria. The authors used a commercial software package SAP2000 to simulate the buckling behavior of multi-story planar steel frames by various bracing parameters to clarify this problem. Results of this study will help structural engineers to understand more clearly these influences, therefore they can choose suitable bracing types for steel frames to ensure technical, economic, and aesthetic factors for practical design.

3D printing technology is now the trendiest term in engineering in general and advanced structural design engineering in particular. Finding structures with optimum geometry and materials that fit the technologies above is difficult. This study presents an approach to creating a hybrid structure by combining Rhino Grasshopper and Karamba3D to replace the hybrid structure reinforced with hard particles presented in Ref. (Tee in Jom 72:1105–1117, 2020 [3]). The proposed hybrid structure is improved from the honeycomb structure by the Galapagos optimization algorithm, one of Rhino Grasshopper's optimization plugins. It considers the properties of materials with a Negative Poisson Ratio (NPR). These material properties were established based on the formulas presented in Sect. 3 using the Karamba3D parametric design tool. The tensile stress–strain curve demonstrates the optimal hybrid structure efficiency compared with the sample without the reinforcement and the two samples with the reinforced hard grain with different printing orientations in 3D printing technology. This demonstration was established using ABAQUS finite element software with the Arruda-Boyce material model for polymer materials.

This study proposes a new modified ACI 318-08 formula based on machine learning (ML) to forecast better the compressive strength of Concrete-Filled Steel Tube (CFST) columns. The prediction ML model is established from 663 experimental samples. CFST columns’ ultimate compressive strength results show differences when comparing experiments with the current calculation formulas using the Linear Regression algorithm to modify the original ACI 318-08 formula by determining the regression coefficient or slope coefficient and the required intercept value. The prediction model with the updated ACI 318-08 formula yields a more reliable CFST column ultimate compressive strength.

The Single Shot Multibox Detector (SSD) technique is currently among the fastest and most accurate detection algorithms available. However, the majority of research on the accuracy of this approach has focused on noiseless objects. Thus, this study evaluates the algorithm's accuracy with both noisy and noiseless objects. To that goal, the algorithm is trained to recognize ten different flower species. Experiments are then carried out on photographs in four different scenarios: the item is totally lighted, 1/3 of the object is darkened, 1/2 of the object is darkened, and the object is fully darkened. The performance of the algorithm is then evaluated using SPSS 20.0 software and the analysis of variance (ANOVA) and least significant difference (LSD). The experimental results reveal that the algorithm accuracy is strongly dependent on the noise level. The detection accuracy is 100%, 81.3%, 44.7%, and 62%, respectively, when the item is fully lighted, 1/3, 1/2 size of the object is darkened, and the object is fully darkened.

Liquid alloy dispersion is considered to be the most popular manufacturing technology of 3D printing metal powder fabrication technology nowadays. This paper presents some research results, design and fabrication of 3D printing metal powder dispersing equipment based on liquid alloy dispersion technology using centrifugal atomization and an inert gas at high pressure. The survey results have determined a set of geometrical parameters and basic specifications for the metal powder dispersing equipment; accordingly, metal powder has been successfully manufactured with the properties that meet the requirements for 3D printing metal technology.

The single point diamond turning (SPDT) method is an ultra-precise machining (UPM) method and holds the unique position in the field of material removal mechanical machining such as turning, milling, drilling, and more. The surface quality produced by the SPDT method is typically characterized by a surface shape tolerance of a micrometer fraction and a nanometer scale surface roughness (RS). Achieving such fine surfaces requires good assessment and control of factors affecting surface quality ultra-precision (UP) products. This paper focuses on surveying the influence of cutting methods (CM) in the SPDT on surface quality in general and surface roughness in particular. The main CM mentioned include Slow Tool Servo (STS) and Fast Tool Servo (FTS). The related research results in the SPDT method and some comments are presented in order to contribute to improving the products surface quality in the SPDT method.

This report presents the study results of defects classification that often appear on garment fabrics and a defects identification model made by artificial intelligence. The classification system of fabric defects is created for the artificial intelligence recognition model to ensure a comprehensive and general overview in many aspects: the type of garment fabric, the stage and causes of the defects, objects and the degree of defects. The recognition model for identification of fabric defects is built on the experimental method using the YOLO algorithm version 5. The data for model training and testing are selected and made by the algorithm's requirements, including 261 samples of fabric defect on 2D images of fabrics that have different characteristics such as weaves, textures, thicknesses, weights, yarn densities, and compositions. The testing results show that the model achieves an average of over 65% accuracy depending on the difficulty of the detected defect types. This model is the initial basis for designing an automatic detection system of the defects for many different types of fabrics.

In this study, the behavior of the One-Way Wide Module Joist Concrete Floor System (OWWMJCFS) is researched by using two methods: hand calculation and the Finite Element Method (FEM) employing SAP2000. For the hand calculation method, the internal forces of the floor are predicted by using the practical parameter tables. With the finite element method employing SAP2000, we simulate the whole of the one-way wide module joist concrete floor system by using a three-dimensional space FEM modeling for predicting accurately the behavior of the OWWMJCFS. Obtained results show that the finite element method employing SAP2000 is much different from the hand calculation method. This study gives some useful advices for practical design engineers.

Hydromechanical forming has been an impressive technology in manufacturing thin-shell products. Under the support of high-pressure liquid, the product can achieve many outstanding advantages such as increasing the level of deformation, reducing thinning, and improving surface quality. Especially, this technology is suitable for specific parts requiring great depth, or complex profiles that are difficult to shape by conventional methods, and one type of them is conical part. There are many factors affecting the product quality, especially the liquid pressure and blank holder force. In order to clarify this issue, in the article, a parametric study on the impact of liquid pressure and blank holder force on the quality of the average conical product is presented using numerical simulation method. The results demonstrate the impact of key technological parameters on product quality, namely the radius at the top of the product and on the thinning of the product. Moreover, the optimal set of parameters to achieve high efficiency in the forming process is also proposed. The investigation is meaningful in predicting the shaping process to give an appropriate control plan.

In recent years, high-pressure liquid forming technology has been widely applied into the manufacture of thin shell and tubular parts. In addition to superiorities including surface quality guarantee and operation reduction, this technology can also improve productivity and product diversity in one forming step by punching pairs of sheet metal. The generated pair of sheets can be symmetrical or asymmetrical. However, assessing the impact of technological parameters on the forming ability of the pair is difficult, especially the products stamped from a pair of unwelded sheet metal. Therefore, in the paper, the effects of blank holder force on cylindrical cup from unwelded pairs of sheets are investigated. Numerical simulation method was selected for study in this issue. The results give an important assessment of the impact of the factor on the shaping ability of the product. Based on these results, controlling stability of the forming process will be more convenient.

Forward-reverse extrusion is a common method in the manufacture of transmission components that require high strength and rigidity. This is a method that helps the metal to deform in two directions: forward and reverse directions compared to the punch movement. However, there are many factors affecting product quality that need to be investigated such as pressing speed, friction, temperature, pressing amount, etc. Therefore, in this paper, the forward-reverse extrusion process of H-shaped products is investigated to clearly evaluate the influence of some essential factors including pressing speed, pressing depth and friction. Numerical simulation method with advantages of convenience, time reduction and high reliability was applied in this study. Research results are meaningful in deforming prediction and the design of extrusion dies later.

Today, 3D printing technology has been applied in industrial applications. However, improving the quality of printed products is still an issue that needs to be studied for this technology to be used more widely. This research proposes the calculation of the inherent strain (IS) value based on the heat affected zone (HAZ). Then, the IS values are used for calculating the deformation of the printed part. HAZ depends on the printing process parameters and material properties. This paper presents method to calculate the HAZ in different plans according to the printing process parameters for printing Ti6Al4V with selective laser melting (SLM) printing method.

In this work, several trenches are placed in the ribs to reduce disadvantages of square ribs. These configurations open up some small extra passages for the coolant to remove the local vortices. Furthermore, the remained square pillars of the ribs act like pin-fins which promote horseshoe vortices. These vortices significantly enhance the heat transfer capability in the junction of pillars and endwall. To investigate the effect of trenches number and shape on the heat transfer capacity of the channel and flow characteristics, a parametric study of ribs with trenches is performed using RANS equations with the SST turbulence model. Furthermore, the staggered and in-line arrangements of ditches are studied. It is concluded that the staggered trenches show a higher Nusselt number than the in-line arrangement, but it comes with a higher friction factor. The parametric study resulted in a higher heat transfer efficiency index (HTEI) of the new designs than the square ribs. At Re = 26,500, the Nusselt number of 3 trenches with staggered arrangement increases by 41.9%. Moreover, a slight increase in friction factor combines with that to form a 31.9% increase in the overall Heat transfer efficiency index. The designs of 3 trenches with in-line arrangement come with a slight increase of 13.7% in Nusselt number; a decrease in friction factor of this design forms a 16.4% increase in Heat transfer efficiency index compared to the case of the original ribs.

Bleeding air in the axial compressor is a well-known method to take air for cooling treatment in the turbine and provide an atmosphere in the cabin. A most common bleed system which is used in gas turbine engine frequently reduce the efficiency and stall margin of the compressor. This study proposes a new bleed air method, the multi-bleed air method, which is enhanced the efficiency and stall margin of the compressor. The multi-bleed air method contains 36 bleed air channels on the rotor domain’s shroud surface. The bleeding system is studied using three different bleed types: single-bleed, double-bleed, and triple-bleed in a single-stage transonic axial compressor, NASA Stage 37. The numerical results demonstrated that the aerodynamic performance of a single-stage transonic axial compressor was improved with the multi-bleed method, including total pressure ratio, adiabatic efficiency, and stall margin compared to the smooth casing case. In addition, the adiabatic efficiency and stall margin increase more in the double-bleed case than in single-bleed and triple-bleed cases.

Warehouse management helps businesses easily capture timely information about goods, supplies, raw materials, and products. Accordingly, business managers can make right plans and decisions, reduce costs, increase competitiveness, and improve production and business results. Warehouse management is one of the indispensable steps in the production and business process. Effective warehouse management helps businesses capture information about products, materials, suppliers, and items simply and quickly. For Vietnamese, small and medium-sized private enterprises, whose issue is even more necessary and should be paid attention to in the current context. This article will study the finished product warehouse of the footwear factory, thereby giving the most objective assessment. The Flexsim tool was used to simulate and analyze the current status of the finished goods warehouse. The results was used to evaluate problems in warehouse management and clarify the operation of this department. Then, come up with solutions to the issues that cause difficulties and greatly affect warehouse operations.

Magnetorheological elastomers are intelligent materials in which many scientists have recently been interested in innovative vibration systems. MRE is made by embedding micro-sized iron particles into an elastomer such as natural rubber. MRE has overcome the disadvantages of magnetorheological fluids (MRF), such as deposition problems, leak problems, and response only under velocity. MRE-based devices have many outstanding advantages in intelligent vibration systems, such as MRE-based isolators, absorbers, and MRE sensors. Mechanical properties, especially the modulus, change remarkably when a magnetic field is applied. MRE-based devices combine with a semi-active controller so that the system can avoid resonance, isolate excitation vibrations, or absorb existing vibrations. These systems can be remarkably effective in car suspension, construction sites, and mechanical systems. This paper aims to provide a comprehensive overview of MRE application aspects, including fabrication methods, properties of MREs, modeling, and applications of MREs in vibration systems.

In this study, SS400 steel plate was used to bend the V-shaped parts with different corner radii and bending angles. Based on the desired angle value, punch radius and bend angle (punch stroke) must be selected to get the correct shape. The combined kinematic/isotropic hardening law was used and shown more accurately than other laws. When comparing with corresponding experiment data was used to predict spring back in V-bending. To decide the punch radius and bend angle (punch stroke) for the desired shape, some values of the punch radius and bend angle (punch stroke) of the V-bending process were first changed to simulate and investigate the corner radius and forming angle of the part after spring-back. A Minitab 17 software tool was used to determine corner radius and forming angle after elastic deformation as functions of punch radius and bend angle. Thereby as a basis for the correct selection of punch radius and bending angle when bending to achieve the value of corner radius and bending angle in later experiments.

This paper proposes a method and results of modeling the thrust force (F) and torque (M) generated by the propeller working behind the hull in water environment for the container vessel Fortune Navigator (CV. FN), that belongs to the Vietnam Ocean Shipping Joint Stock Company. The input data for modeling consists of periodic-changing signal pairs (F, M) that are obtained by authors from the hull–propeller numerical simulations for CV. FN using CFD method and commercial software STAR/CMM+. The input database is obtained based on design of experiments (DoE) for CV. FN with: Draft varies from ballast to full load; the draught difference (Trim = TA − TF), considered as a disturbance (where: TA—draft of the aft, TF—draft of the forward) and the changing propeller speed. The propeller’s excited force/torque are transformed from the time domain to the frequency domain by the FFT method after re-sampling twice the input data. This implementation method ensures that the data is sampled in a constant time step, and the sample number of the extracted data vectors (T and M) is applied to the exact FFT-algorithm. The database obtained from processing F and M signals in the frequency domain is the input for regression modeling to determine force and moment components according to the impact factors. Research on signal processing and modeling the forces and moments are carried out on the LabView (NI, USA Company).

Working regime (WR) of the main propulsion plant (MPP) with marine diesel engine (MDE) is the established parameter set of: MDE’s power; rotary speed of propeller (or engine); ship’s speed (Pw-n-V), [kW—rpm—knot], so that the MPP’s major components are not subjected to mechanical and thermal overload. The WOR is established in accordance with the followings: Real operation conditions of hull and propeller; uniform working cycles of the MDE’s cylinders; fuel consumption characteristics of the MDE. The selecting WOR was carried out on the base of: digital databases constructed during the design and construction phase of the ship MPP; result of predicting misfire states of cylinders and an established optimal functional. The instantaneous power signal is calculated by product signals of the instantaneous torque and average rotary speed. The WOR forecasts were verified for the MPP of the MV.HR34000DWT using the simulation software programmed on LabView, at the normal working sea-conditions.

This paper studied the resonance regimes of the torsional vibrations on the Main Propulsion Plant (MPP) using the two-stroke marine diesel engine (MDE) type MAN-B&W 6G70ME-C9.2, measured on the sea-trial test before the handover. The new physical phenomenon was gotten: turbulences, unfocused the phases in cycles of the first mode resonance. The requirement was to model the relationship and impact between the torsional vibration and the burning process in each of the engine cylinders. The authors investigated the indicator diagram p(φ) inside the cylinder when changing the phase of fuel distribution, in order to explain the physical nature of turbulence of torque in the resonance mode. The authors proposed the mathematical model with the small parameter for the torsional vibration system in the propulsion system of the MDE at the risk resonance mode.

This article explores the effects of structural characteristics on the quality of dome-shaped hot-pressed products made from infrared optical ceramic materials. The research simulated the effect of the coefficient of friction between the mold cavity and the injection mold material on the pressed product’s uniformity. Simultaneously, practical experiments are used to validate the simulation findings.

This work examines the free oscillation characteristics of FG microbeams supported by an elastic medium while accounting for a geometric flaw. The finite element formulations are developed using the FEM, high-order shear strain theory, and modified coupling stress. This hypothesis does away with reduced integrals and shear correction factors.

With compliant foil structure, bump-foil bearing, one type of foil-air bearing, has been widely applied in high-speed machines thanks to oil-free operation. In this paper, two types of experiment have been implemented to study dynamic behaviour of this foil bearing. Before that, one bump-foil bearing structure was manufactured with two kinds of material: the foil structure made of stainless steel 304 with 0.1-mm thickness and the bearing body made of stainless steel CT3. Static-shaft experiment was deployed to compute the nominal stiffness of the foil structure through load–displacement relationships. The data shows the same tendency with computed results from a mathematical model of foil structure proposed in the previous research. Differences can be reasoned by manufacturing error. Moreover, through rotating-shaft experiment, air thin film is proved to appear inside the bearing, and aerodynamic pressure bears a significant influence from rotating speed. The study demonstrates important meanings in confirming the theoretical model of foil structure and shaft-bearing system.

This investigation studies the free vibration response of micro FG beams on elastic foundations with geometrical imperfections. Finite element, high-order shear strain, and modified couple stress theories compute formulas. High-order shear deformation theory removes reduced integrals and shear correction factors. Calculation results are essential for designing, manufacturing, and operating beam constructions that revolve around a fixed axis.

This paper presents the preliminary research findings on the influence of high-speed and heat-assisted machining on the performance of cutting tools while milling heat-treated SKD61 steel. The study involved two types of cutting tools, namely uncoated and coated. The results indicated that when finishing milling at 0.15 mm/tooth feed rate and 0.3 mm depth of cut at 300–600 rpm and 500 ℃, uncoated cutting tools were not suitable for machining heat-treated SKD61 steel highway strips. However, coated cutting tools with high-speed machining up to 600 rpm could machine the steel with the aid of heat in the range of 200–500 ℃, a feed rate of 0.15 mm/tooth, and a depth of cut up to 0.5 mm.

This paper comparatively shows the confined compressive strengths of normal concrete (NC) and high-performance fiber-reinforced concrete (HPFRC) in experiment and model. Two types of compressive specimens were designed: no cover and uPVC cover with a 3.2 mm thickness. The applied load was directly applied on the NC/HPFRC core during testing. All NC/HPFRC cores were cylindrical with an identical size as follows: 114 mm in diameter and 600 mm in height. A hybrid fiber system, consisting of 1.0% long hooked and 0.5% short smooth fibers by volume, was used in the HPFRC core. The effect of confinement on axial compressive strength of the NC/HPFRC cores were clear. Besides, the models using Mohr–Coulomb principle and Hoek–Brown principle were also built to forecast the compressive strengths of them.

The Demand-Driven Material Requirements Planning (DDMRP) is a new approach that combines the advantages of both push and pull systems. Specifically, DDMRP works based on a combination of principles of core MRP, theory of constraints (TOC) and just-in-time system (JIT). Nevertheless, not many studies have been found in the literature analyzing the implementation of DDMRP in actual production conditions. Besides, the researchers have not yet proposed any method of implementing DDMRP. Therefore, this study aims to propose a model for DDMRP implementation and apply it to a plastic manufacturing company to analyze the possibility of implementing DDMRP in the actual production environment. This study is conducted through two main methods are desk research and case study. The case study selected to collect data is a company operating in the manufacturing sector and has a multi-level material structure. It also proposes opportunities and challenges that should be addressed by future studies.

TiAlCN coating is often used to improve properties of engineering surfaces of a variety of applications such as in the mechanical, medical or decorative fields. In this study, the effect of N2/C2H2 gas ratio static friction and color (through wavelength measurement) of TiAlCN films created by vacuum arc deposition technology was investigated. The TiAlCN coating is fabricated on the surface of SKD61 steel. Using a home-built deposition system, namely HCM-700 (Hard Coating Machine—700 mm in chamber diameter). The static friction of the coated sample is evaluated with that of the uncoated ones. For the color determination, a spectrophotometer was used to analyze the energy present at each wavelength of the coating spectrum. The results show that when the N2/C2H2 gas ratio increases, the static friction of the TiAlCN coating decreases and the color of the coating becomes darker (i.e. increasing wavelength).

The distribution of car braking force according to the traction conditions of the wheels with different types of roads in order to increase the braking efficiency and the safety of the car’s movement. In this paper, the authors have built a three-dimensional dynamics model to investigate the influence of brake force distribution on the braking efficiency of a car. The survey results using Matlab software show that: if a Kia Pride CD5 car is driven on a straight road with a maximum coefficient of longitudinal friction μxmax = 0.8 at 90 kph, and then the car is suddenly braked with a braking torque equal to the maximum braking torque; In case the car does not have a mechanical brake force distribution system, the rear wheels are locked and slip completely, causing the car to lose its motion stability; If a car with a mechanical brake force distribution system, the wheels will not be locked, the force generated when braking of the rear wheels will increase by about 25%, the car’s braking acceleration will increase by about 15%, the braking efficiency will be satisfactory according to the standards ECE-R13 (The international braking regulation of the UNO-economic commission for Europe in Geneva—ECE-regulation No. 13, ECE-R13, Vehicle Regulations, [1]).

This paper shows the results of building a model and simulating the effects of the ratio of grip to the ratio of slip when the semi-trailer is braked at 60 kmph on a straight road. The system of dynamic equations of the semi-trailer is built by the Newton–Euler method. Simulation of the influence of the ratio of grip on the ratio of slip using Matlab software. The results showed that, if the semi-trailer is moved on a straight road with the ratio of grip μxmax = [0.8:0.1:1.0] at 60 kmph, the longitudinal ratio of slip is less than 10%, the brake force reaches the maximum value. If μxmax = [0.5, 0.6], the ratio of slip of the middle axle, and rear axle reaches the maximum value, S = 100%, the wheels are locked and fully slipped, the brake force reaches min value, and the semi-trailer is not safe.

This paper presents the results of a numerical simulation of the performance of the DA465QE engine and the impact of adding HHO to biogas on its efficiency and pollutant emissions. The results showed that at a given operating condition, an increase in HHO and CH4 concentrations, as well as the load regime, led to an increase in the indicative work cycle Wi. However, this increase decreased as engine speed increased and reached a peak value when the equivalence ratio and advanced ignition timing varied. Additionally, an increase in HHO and CH4 concentrations, the load regime, and advanced ignition timing was found to result in a rise in the combustion temperature T and NOx content in the exhaust gas. But, when engine speed increased, a decrease was observed, and a peak value was achieved with variations in the equivalence ratio. The rate of increase in NOx concentration with the equivalence ratio was found to be higher than that of Wi and T. When the HHO concentration in the biogas mixture was below 30%, the improvement in Wi was observed to be beneficial before the increase in NOx. Given that the biogas engine operates with a lean mixture, the addition of HHO is especially intriguing. The optimal ignition timing was found to reduce 6CA as effectively as adding 30% HHO to biogas at a certain engine speed. By properly adjusting the engine's operating parameters when using HHO-enriched biogas as fuel, a balance between performance and NOx emissions can be achieved. A compromise between performance and NOx emission can be obtained by appropriate adjustment of operating conditions of the engine fueled with HHO enriched biogas.

Our work aims to develop a vibration generator that generates electrical energy from surrounding mechanical vibrations. This generator represents an alternative to powering wireless sensors without using primary batteries. The generator is an electromagnetic induction generator. When the generator is excited by ambient vibration, the resonant mechanism induces the relative motion of the magnetic circuit relative to the copper coil. This relative motion generates voltage across the coil due to Faraday's laws. This energy harvesting technology has advantages over conventional types concerning size and efficiency, and it is incredibly robust and has low electrical impedance. The generator model can be excited by sine, random, or actual vibration data, and can be easily scaled up to increase the output power in order to generate an expected output power.

The silicothermic reduction process under vacuum is currently the main method for the production of metallic magnesium from calcined dolomite ore. In this paper, the experimental data from ThanhHoa dolomite ore reduction investigations are used to analyze the kinetics of the reduction process of calcined dolomite. Several kinetic models have been investigated to evaluate the rate control step of the reduction reaction. The results show that solid-state diffusion is the controlling stage of the reduction reaction. The activation energy of the reduction reaction under vacuum is 203.2 kJ/mol. Experimental factors affecting the reaction rate are studied, including temperature, ferrosilicon ratio, briquetting pressure. From the analysis results, it can be determined that silicon diffusion is the main factor controlling the diffusion phase.

The drive axle consists of the last elements in the transmission of power from the engine to the driving wheels. The drive axle has three main components: the main transmission, the differential, and the half-shaft mounted in one housing. In there, the axle housing is the part containing all the power transmission components, at the same time it acts as a beam to support the weight of the vehicle body and is subjected to loads from the wheel-road interaction. During operation, the axle housing direct load from self-weight and indirect load from moments of torsion and bending moments. Due to the above loads, the axle housing will be deformed, cracked, and even broken. This paper presents the research results on the evaluation of the fatigue strength of the drive axle housing on the multi-purpose forest fire fighting vehicle, according to the research results, the author has determined the working life of the axle housing when the vehicle moving on the road according to ISO 8608:1995, at the same time, the axle housing structure is proposed to ensure durability.

This research focuses on design and experimentally testing of a sealing component featuring magneto-rheological fluid for rotary shafts. The working fluid is a lubricant. From review of previous researches on application of MR fluid in sealing, a configuration of a rotary MRF seal for a working lubricant is proposed. Optimal design and modeling of the MRF seal are then realized based on finite element analysis. From optimal results, MRF seal prototypes are manufactured and experimentally tested. The results are then compared with counterpart conventional lip-seals.

The honeycomb panels are complex structures whose modal characteristics depend on several factors such as geometry and materials. Therefore, this study aims to investigate the impact of geometrical and material variation on natural frequencies and the mode shape of the honeycomb structure. The research approach is based on the analysis and simulation of a honeycomb plate model by the finite element method in ANSYS 2022R1. All the honeycomb models in the simulation are applied to the same clamped-free boundary condition and their covers are made of carbon fiber-reinforced epoxy composite. A validating model which is equivalent to the previous research is carried out to evaluate the reliability of the paper, the difference between four natural frequencies between the two research is less than 9%. With the same geometry conditions of honeycomb structure, the natural frequencies the aluminum and Nomex cores produce are considerably more than the values of polypropylene. The increase in the core thickness leads to the growth of the natural frequency values in longitudinal bending modes, but the decrease in lateral bending modes. In terms of the cell size, there is a rise in the first six eigenfrequencies of honeycomb structure when expanding the size of the unit cell from 2 to 6 mm.

The paper proposes an anti-vibration system to protect equipment and people under the impact of earthquakes. The seismic isolation design consists of 2 floors system that reduces the acceleration and vibration of the object on the top floor. A hedge algebras-based controller (HAC) is applied to increase the system’s stability under earthquake excitations. Earthquakes with different properties are also given as input to verify the system's performance. A conventional fuzzy set is designed based on HAC analog parameters. Numerical results indicate the effectiveness of the proposed method with previous method. Moreover, the experiment results also confirm the performance of the controller.

This paper presents research results on the influence of high annealing technology parameters on turbine shaft mechanical properties in turbocharger turbine structure made of 42CrMo steel. The study has established a regression equation showing the relationship between mechanical output factors according to high annealing technology parameters. The research has also determined the optimal value of the technological parameters when highly tempering the turbine shaft.

Currently, the world towards the use of recycled materials from industrial agricultural waste not only contributes to economic development but also contributes to environmental protection—sustainable development. Use of agricultural wastes such as rice straw, rice husk, wood fibers, etc. as additives are increasing. In this study, the potential use of industrial from leather tanning (chrome tanning shavings, CTS) and agricultural wastes (rice husks, RH) as a additive materials for insole for shoe. Thermoplastic rubber (TPR) is selected as the substrate polymer for the synthesis of new materials. CTS released from leather tanning and rice husks from agricultural activities were used in powder form with various percentage to synthesize different composites. These composites were tested for various mechanical properties as hardness, specific gravity, tensile strength, abrasion and tear strength. The addition of any filler improves the mechanical properties of the material. The results showed, rice husk powder (5%, w/w) and chrome tanning shavings (20%, w/w) were the appropriate concentrations studied. The mechanical properties have been determined in insole such as specific gravity (0.895 g/cm2); hardness (69 shore A); tensile strength (58 kg/cm2); abrasion (189 mm3) and tear strength (33 kg/cm). Rice husk make the material properties better than no filler composite. This contributes to promoting the development of recycled materials towards sustainability in the future.

This article presents about the influence of recrystallization annealing temperature on the microstructure and ductility of Al–Zn–Mg–Cu alloy. This alloy was modified by La and Ce, uniformly annealed and cold rolled with 275%. After the cold rolling process; the structure of the alloy has a grain size of less than 10 µm. The alloy is heated at the other recrystallization annealing temperature for 2 h. Research results show that with recrystallization annealing temperature at 450 °C for 02 h; the microstructure of this alloy is α phase which has a grain size of less than 10 µm; the structure of the alloy is uniform. In addition, the intermetallic phase Al11Ce3 and Al3La are finely dispersed in the matrix. With the structure of this alloy, the ductility of the alloy reaches 667% when tensile is performed at 400 °C. The mechanism of high ductility has also been determined for Al–Zn–Mg–Cu alloy as the grain fine mechanism; uniform and dispersed high hardness particles which increased ductility of the studying alloy.

In electric car transmissions, multi-speed transmissions provide operating modes to suit different travel needs and thus contribute to the vehicle's desired performance with minimum energy consumption. However, multi-speed gearboxes are not widely used in the electric car manufacturing industry because the car jerks during gear changes, causing energy loss and making passengers uncomfortable, which is incredibly annoying for people with motion sickness. To solve the above problem of the multi-speed gearbox, in this paper, the authors present an alternative to design a gearbox using non-circular gears to provide continuously variable torque during gear shifting. A control strategy is also proposed to provide the same shifting flexibility as an internal combustion engine transmission. On that basis, a calculation and design program was written on Matlab software to verify the theory. The results show that the new design solution has overcome the disadvantages of the traditional multi-speed gearbox in electric cars.

Eccentric elliptical gears are a special case of non-circular gears used in generating gear drives with variable gear ratios. This type of gear can create a speed increase and reducer of the output shaft relative to the input shaft in one working cycle. In this study, the authors present a method to establish computational expressions for the geometrical design of a pair of improved cycloid profile eccentric elliptical gears taking into account avoiding undercutting. First, a mathematical model of the centrode of an eccentric ellipse gear pair is established. After, the mathematical equation describing the tooth profile of the eccentric ellipse gear is established based on the theory of the enveloping by rack cutter with an improved cycloid profile. Based on research theory, this research wrote a numerical calculation program for the survey and design purposes on Matlab software. Since then, a pair of eccentric elliptical gears has been manufactured on a 3-axis CNC milling machine to demonstrate the practicality of the research theory. Experimentally manufactured gear drives the output shaft has a variable speed and torque range from 0.33 to 3 times versus input shaft, which makes it different from traditional circular gear drives and conventional non-circular gear pairs.

Unlike traditional designs, the novel Lobe blower proposed recently by the authors has two completely different rotors, which are developed based on the meshing principle of the oval gear pair. Each rotor has two tooth pairs that are symmetrical according to the two semi-axes of the base oval. The paper presents the influence of the base oval's geometric design coefficient λ (equalled to the ratio of the semi-minor axis and semi-major axis) on this novel blower's flow rate and pressure. The CFX module of Ansys software calculates six blower designs with different coefficients numerically λ. The k-ε turbulence model also considers the kinematics and dynamics of the airflow through the blower. The numerical calculation results show that the design coefficient λ is a factor affecting the dimension, flow rate, pressure, and airflow quality at the blower outlet. Specifically, for blowers designed with a small coefficient λ, the average flow rate can increase from 0 to 32% compared to λ = 1, and the dimension of the blower can decrease from 1 to 21.43%.

The dynamics problem is essential in designing dynamic control laws for tracking autonomous mobile robots (AMR). Differential-driven mobile robots (DDMR) among AMR are commonly researched and applied. Thus, this article focuses on modelling and simulating the dynamics of a DDMR when moving on an arbitrary trajectory. The reverse dynamics model of a DDMR is established, taking into account the sliding phenomenon between the wheel and the road surface. The coefficient of friction is determined experimentally based on a platform DDMR and an S-type load cell. NURBS interpolation is used to design the motion trajectory of the DDMR in the general case. The research results have important implications for designing kinematics and dynamics controllers for the DDMR to follow a complex trajectory without slipping at a certain speed.

Vehicle vibration is a problem that is currently in need of research attention to improve the quality of automobile exploitation. The suspension system directly affects vibration as well as safety and performance. It helps control and suppresses the vibration of the road acting on the chassis, helping the vehicle to move stably and the passengers on the vehicle to feel smooth. The design to optimize the suspension, more specifically the damping is being interested in and developed, one of the ideas is to add shock absorbers using magnetorheological fluid, which can change the viscosity by electricity. This study will simulate the traditional suspension system and the suspension system with the addition of using magnetorheological fluid dampers (MR dampers) when the vehicle moves into different profiles on the road. MR dampers are activated and supplement the damping force for a certain period to quickly reduce the amplitude of the vibration, test with different values of the force from the MR damper to evaluate and select the most reasonable value. The results show that the body vibration amplitude is improved, the ability to suppress vibration increases, the shake angle of the vehicle body decrease, respond the smoothness, and increase the convenience of the car.

The anti-roll bar has the effect of increasing the stable motion of the vehicle. It has the role of receiving, transmitting force and torque between the wheel and the chassis, reducing the vibration frequency of the car, ensuring the smoothness and stick on the road of the vehicle. Therefore, this paper conducts research on “design and durability test of the main assemblies of active anti-roll bar”. The active anti-roll bar uses MR fluid, the design of the magnetic brake assembly replaces two rubber bearings on the conventional anti-roll bar, this is also the position to increase the torque for the bar. The article conducts research and simulation with different materials, in different working modes to evaluate the durability of the bar, and gives the most suitable results for the design, ensuring the durability detail. At the same time, evaluate and give suitable materials for the MR brake assembly.

In this study, braking torque characteristics of a disc-shaped Magnetorheological brake (MRB) structure are determined on the test platform. The primary purpose of this study is to determine the relationship between the generated braking torque depending on the current supplied to the coil on the MRB device. The process of determining the brake torque characteristics on the test platform consists of three steps. In the first step, the study deals with the magnetorheological fluid (MRF) characteristics and the MRB structure. In the second step, a brake test platform is built to measure the torque generated on the MRB. In the third step, the measurement procedure on the platform is introduced, and experiment results are analyzed. These results show that the relationship between the generated braking torque depends on the input amperage. The study’s results confirm the effectiveness of magnetorheological fluid in highly appropriate scientific and technical fields.

Renewable energy (RE) is the most priority issue to keep global sustainable development with a non-pollution environment, non-gas emissions, and no global warming. Renewable energy is generated from renewable sources that immensely exist in nature such as wind, solar, ocean, bioenergy, and geothermal energies instead of fossil energy sources with many harmful problems for human health and environment. This paper reviews recently RE technologies and successful lessons from applying modern science and technology in developing renewable energy for a sustainable economy, society, and industrial development in leading countries of sustainable energy development. The results hope that renewable energy will be bloomed in research and practical application all over the world.

There are three types of automotive assembly on the line: conventional assembly, automatic assembly and modular assembly. Modular assembly is the use of an integrated model of modules in the design and manufacture of cars and its parts on the basis of applicable standards. The article analyzes the key elements of the application of the modular assembly for automotive manufacture in order to increasing the performance of the assembly line. The results show the high performance and performance of the automobile assembly. They also show two key factors: the level of modularization of the assemblies and the use of standards in assembly.

Aircraft landing speed is usually high, and the effect of the braking system is important. Besides, the braking system will work more efficiently when combined with a thrust reverser. Nowadays, research, design, and building of thrust reverser on aircraft engines is a particularly challenging problem due to the inherent complexity. This study presented the aerodynamics characteristic, performance, efficiency, and stability of a Turbofan Engine with multi-door crocodile thrust reverser system by using 3D RANS equations with scalable wall function k-ε turbulence model. The design of multi-door crocodile thrust reverser system changes correspondingly to the variation of the opening angle of the outer doors, combined with the inlet Mach number. The results indicate a stable progress operation of the thrust reverser, safety, and the best performance. The results of reverse thrust efficiency reach maximal values at the opening angle of outer doors α = 50°.

The grinding method is often used for finishing parts made of materials with high mechanical strength and hardness. When manufacturing parts with high hardness such as heat-treated steel, grinding methods are often used to ensure dimensional accuracy, surface roughness. This paper presents experimental research results on the process of cylindrical grinding tempered alloy steel on CNC cylindrical grinding machines. The effects of process parameters such as workpiece speed, feed rate and depth of cut on the surface roughness and dimensional precision of parts are studied. Experimental setup and investigation of the contribution of process parameters to the characteristics of the part have been carried out on the basis of the application of Taguchi technique and analysis of variance (ANOVA). Besides, the optimal sets of parameters to achieve the smallest roughness and the highest machining accuracy have also been determined in turn. The multi-object optimization problem to achieve the minimum roughness and the highest machining accuracy at the same time has been solved on the basis of a combination of Taguchi technique and grey relation analysis (GRA).

This paper examines the structure of a vehicle when it collides with a Moving Deformable Barrier (MDB) using a computer simulation model. The model was created to simulate actual test conditions created with Hyper Mesh and LS-DYNA software. The crash simulation results were then compared to the rating guidelines of the Insurance Institute for Highway Safety (IIHS) to evaluate the overall vehicle structure and measure intrusion. This study utilized a full vehicle finite element model to construct a crash analysis model in accordance with the IIHS side impact test regulations and conducted a crash analysis. The results were then compared to the actual vehicle crash test results to validate the analysis model, and a side body member that had a significant impact on the side impact performance was identified using the verified analysis model. The crash analysis using finite element models revealed that the most severe damage to the vehicle frontal structure occurred when the vehicle model collided with the Moving Deformable Barrier on the left side of the vehicle model. This study concluded that the B pillar and proof need to be improved to achieve a higher rating from the IIHS.

Titanium nitride (TiN) thin film has been used widely in surgical instruments, and dental and medical implants providing an inert surface barrier that protects the products from corrosion and improves the wear resistance. By adding silver (Ag) to TiN, titanium silver nitride (TiAgN) is predicted to be able to perform the antibacterial effect. In this work, a co-sputtering technique was employed for TiAgN fabrication. Pure titanium and silver targets were sputtered by DC (direct current) and pDC (pulse direct current) powers, respectively. The pulse frequency of pDC power was varied to examine the coating’s constituent, microstructure, and formation velocity. The chemical composition of the coating was investigated by the Energy Dispersive Spectroscopy (EDS), whereas the morphology and thickness of the coating were observed by Field Emission Scanning Electron Microscope (FESEM). The experimental results showed that TiAgN coating was well formed on Si wafers. The pulse frequency strongly affected composition and morphology, and the Ti/Ag ratio of the coating as well. At 70 kHz, the TiAgN coating has the highest dense structure and fastest formation velocity. After that, TiAgN was coated onto prosthetic eyeballs made of PEEK (Poly-ether-ether-ketone)—a popular material used in biomedical. Preliminary examination indicated that there is no dispersion of TiAgN coating to tissue that is directly in contact with the implant coated ball.

This paper presents the estimation of the uncertainty of the torque standard machine manufactured and integrated at the Vietnam Metrology Institute. The uncertainty is composed of the uncertainty of component quantities such as arm length, weight, frictional moment, shaft tilt, and load oscillation… From that, an estimate of the uncertainty of the primary torque standard was made. The machine with dead weight is designed in the torque range of 2 kNm, horizontal shaft, integrated with rotary air bearing to minimize the coefficient of friction. The standard arm of the machine is made from Invar material, has a low coefficient of thermal expansion, has an adjustment to compensate for manufacturing errors, and ensures the standard length. This research is one of the national projects aimed at creating the primary torque standard machine in Vietnam of 2 kNm with measurement uncertainty 5 × 10–4.

The rear axle housing of the truck receives the load directly from the weight of the cargo and the vehicle's mass and causes an indirect load of torque, bending leading to deformation, cracking, and possibly breakage. Truck's rear axle housing are usually made from main materials such as cast steel, welded steel or cast iron. In the general case, stress and strain analysis when is subjected to bending will predict the failure modes for design and manufacturing. Finite element method (FEM) and simulation in Ansys Workbench 2022R1 software were used in this study. Some composite materials are selected to replace the original material to casting and welding technology replace and reduce the overall mass of trucks. The results of stress and strain analysis on 3 types of materials (steel, cast iron, composite) shown that the maximum value of equivalent stress (von-misses), maximum principal stress, and the maximum shear stress. The crack analysis results shown that the maximum value of J-Integral. When replacing composite material compared with the original material, the mass of the rear axle housing was reduced by 54%, and reliability and durability were also improved.

A study on the stamping process of a chair surface with complex profiles made from SS400 material sheets, this part is welded to the mounting bracket used for transporting mining workers in the mines. During the stamping process, the seat surface often appears tearing at the front position of the seat. This position has non-uniform deformation, a large degree of deformation is easy to tear, and the surface after deformation will be uneven, affecting the quality and aesthetics of the product. Defects occur when stamping the seat surface due to many reasons such as the calculation of the initial profile of the workpiece, selection of geometrical parameters, and inappropriate technology. Therefore, this study has conducted a simulation of the stamping process with different types of billet profiles, after being simulated stamping, the deformation and thickness will be determined at many locations. From there, select the appropriate billet profile so that the part after stamping does not appear to be torn, ensuring the size requirements and no need to add rim cutting operations. The suitable workpiece profile will be simulated and verified with the corresponding experiment.

This study optimizes and determines effect of HVOF (High-velocity oxygen fuel) spraying parameters to porosity of the WC-12Co coatings sprayed on inner cylindrical surface of S40C steel pipe. The studied spraying parameters include: Spray distance (L); Powder feed rate (P); Surface velocity of substrate (V). Experimental parameters using Taguchi L9 orthogonal design. The results determined optimal spraying parameters L3 = 0.3 m; P2 = 26 g.min−1; V2 = 0.15 m.s−1) for the minimum coating porosity with 1.19%. Effect of spraying parameters on porosity is L (46%) > V (34.1%) > P (14.2%). An experimental function for the relationships of porosity with spraying parameters was built to evaluate of influence of research spraying parameters on porosity.

This paper presents the optimization results of automatically welding technological parameters of joint welding for narrow gap welding SAW, including: Welding amperage (Ih), velocity (Vh) and voltage (Uh) to ensure the maximum weld tensile strength. After determining model, the welding is carried out according to Taguchi experimental design with L9 array together with analysis of ANOVA variance to optimize technological parameters and evaluate their effect on tensile strengths of welding metal. The results give an optimal technological parameter that improve the tensile strength and their influence. Reliability of the optimal results has been confirmed through control experiments.

In this paper, the authors present the design automation of three-dimensional (3-D) models of moldbase for two-plate plastic injection molds. Design automation of moldbase is an important stage in the mold design process, because it helps to reduce errors and time spent on tedious, repetitive modeling tasks. VBA programming language was used to build an automation tool for quickly designing of a moldbase with various input geometrical parameters. The input geometrical parameters of the moldbase can be customized by the user or defined according to the moldbase supplier’s catalogues. The VBA design automation tool was implemented in Catia software and Microsoft Excel in order to rapidly create moldbase for two-plate injection mold design. The results show that the various moldbase can be rapidly created using the tool developed in this study. This demonstrates that the tool can be further developed for design automation of subsequent stages in the mold design process as well as enormous potential application in designing products in plenty of other areas.

In this paper, the authors developed a 4 axis high precision milling machine and using the machine to study the effect of cutting parameters on the surface roughness during high speed milling of CuZn40Pb1 brass alloy material. During machining process, the cutting forces and spindle vibration were measured to investigate the cutting forces and vibration for all the cutting conditions. Moreover, an equation of surface roughness as a function of spindle speed, feed rate, and depth of cut was established based on linear regression with least squares method. It is found that the regression equation of surface roughness shows good accuracy and agrees well with the experimental results. Moreover, the validation experiments were also conducted to evaluated the accuracy of the regression mathematical function of surface roughness. It is found that the maximum errors of the surface between validation experiments and the regression function is less than 15% which is relative small and acceptable.

Nowadays, automatic workpiece feeding lines and CNC machining integrating many operations to process machine parts are used more and more widely. These systems operate with high stability, accuracy and flexibility when changing different product types. In this study, an integrated CNC machining and automatic workpiece feeder system were designed and fabricated. This is a modern system, that increases machining productivity and ensures operator safety. The design system includes a conveyor that transports the workpiece to the machining location and transports the part after the processing is complete to the container, a robotic arm that picks the workpiece from the conveyor to the CNC machining machine and picks the part after processing on the conveyor. The results of the research can be applied in production or training in programming, operating automatic workpiece feeding systems and integrated CNC machining.

The primary challenge for successful 3D concrete printing is the complicated characteristics the materials should own, especially printability. The result and the slump-flow tests probably determine this parameter. Unfortunately, the traditional slump and slump-flow test methods are basically based on length and time measured by a ruler and a stopwatch then the result may reflect error caused by human. We introduce in this research an efficient method for slump and slump-flow test data receiving with Kinect v1. Our approach is based on the non-contact measurement and data processing. After capturing the dynamically changing 3D surface of concrete using a 3D device during the test, the results are processed into a point cloud. The slump flow diameter and height at any location simultaneously can be indicated from this point cloud. Finally, the experimental results show that the efficiency of the proposed method is significantly improved.

In this study, the Incremental Sheet Metal Forming (ISMF) simulation was conducted using Abaqus 6.13 software for SUS 304 sheet material at elevated temperature. The Taguchi experimental method was applied to investigate the impact of three technological parameters, namely part temperature (T) ranging from 100 to 400 °C, the step in the z direction of the tool (z) ranging from 0.2 to 0.5 mm, and tool diameter (D) ranging from 6 to 12 mm, on the forming angle. A regression equation was developed to predict the forming angle based on these input parameters. The results showed that temperature (T) had a significant effect on the forming angle, whereas the influence of tool diameter (D) was the least significant. The simulation predicted the largest forming angle to be 76.08°.