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This article aims to present our experience with transmedia storytelling in the design of materials selection, integrating two disciplines within an undergraduate mechanical engineering curriculum in Brazil. The students' project involved developing a narrative within the fictional universe of superheroes while exploring material properties using Ashby's methodology. The study aimed at answering two key questions: (1) Can transmedia storytelling contribute to student learning and skills development? and (2) What are the difficulties when using this methodology? Three evaluation approaches were used: test scores, students' perceptions, and our observations of students' skills development during this project. It was observed that participating students demonstrated significant test score improvements, indicating enhanced learning, with reported challenges in effort and skill development, particularly in story creation and teamwork. Ultimately, this project allowed students to achieve several cognitive learning objectives, fostering the development of crucial skills like communication and problem-solving. The use of transmedia storytelling in undergraduate engineering courses has the potential to facilitate the cultivation of essential competencies for future engineers across a varied range of cognitive levels, albeit requiring considerable time for planning strategies and creating content. [ABSTRACT FROM AUTHOR]

Assessing the sustainability of material-based products now encompasses social sustainability, a vital aspect often overlooked. Even though the existing frameworks provide a starting point, they do not often differentiate between the assessment criteria when making comparisons within one specific material category, which has made sustainability assessments more focused on environmental and economic aspects. This study addresses this critical gap by pioneering a social assessment framework curated to help practitioners to choose the most sustainable cement type out of the standard cement types used in the industry. Utilizing the Fuzzy Analytic Hierarchy Process (FAHP) and linear-scoring method, criteria weights were systematically assigned based on scoring by industry and academic experts. The findings highlight the importance of integrating social sustainability with environmental and economic factors in cement selection. Unlike traditional material selection, which primarily considers cost and performance, green material selection emphasizes the holistic impact of materials, including social factors. Variations in weightage decisions among experts highlight the influence of practical experience, research interests, and context. Functionality emerges as a crucial criterion. The ranking of cement types based on social scores places CEM II/B-M at the top, followed by CEM IV/A, CEM II/A-S, CEM II/A-V, CEM I, and CEM II/A-LL. The evolving nature of sustainability necessitates ongoing research to refine and expand existing frameworks for a more sustainable construction industry. [ABSTRACT FROM AUTHOR]

Motivated by a design of a vertical axis wind turbine, we present a theory of dynamical similarity for mechanical systems consisting of interacting elastic solids, rigid bodies and incompressible fluids. Throughout, we focus on the geometrically nonlinear case. We approach the analysis by analyzing the equations of motion: we ask that a change of variables take these equations and mutual boundary conditions to themselves, while allowing a rescaling of space and time. While the disparity between the Eulerian and Lagrangian descriptions might seem to limit the possibilities, we find numerous cases that apparently have not been identified, especially for stiff nonlinear elastic materials (defined below). The results appear to be particularly adapted to structures made with origami design methods, where the tiles are allowed to deform isometrically. We collect the results in tables and discuss some particular numerical examples. [ABSTRACT FROM AUTHOR]

ObjectivesThis study takes a typical pressure hull segment of an unmanned underwater vehicle (UUV) as the object and explores its load bearing capacity law based on lightweight design technology. MethodsFirst, several typical materials are analyzed using the mechanical properties of the pressure hull, load law and optimal critical load design value (stress strength failure and stability failure occur concurrently). The bearing properties of a typical pressure hull with varying depths are then discussed further in terms of the specific engineering requirements. ResultsThe failure mode of the shell gradually transitions from stability failure to strength failure as the depth increases, and the optimal critical load design value is proportional to the qualities of the material. Taking bearing efficiency and other factors into consideration, aluminum alloy shells should be selected within the 300 m depth range, titanium alloy and glass fiber composite shells within the 300−600 m depth range, and titanium alloy and carbon fiber composite shells within the 600−1 000 m depth range. In the 1 000−3 000 m depth range, a carbon fiber and boron fiber composite shell is the ideal solution. ConclusionsThe findings of this study can be used to guide the design of pressure hulls for UUVs made of various materials.

Abstract Background This Finite Element Analysis was conducted to analyze the biomechanical behaviors of titanium base abutments and several crown materials with respect to fatigue lifetime and stress distribution in implants and prosthetic components. Methods Five distinct designs of implant-supported single crowns were modeled, including a polyetheretherketone (PEEK), polymer-infiltrated ceramic network, monolithic lithium disilicate, and precrystallized and crystallized zirconia-reinforced lithium silicates supported by a titanium base abutment. For the static load, a 100 N oblique load was applied to the buccal incline of the palatal cusp of the maxillary right first premolar. The dynamic load was applied in the same way as in static loading with a frequency of 1 Hz. The principal stresses in the peripheral bone as well as the von Mises stresses and fatigue strength of the implants, abutments, prosthetic screws, and crowns were assessed. Results All of the models had comparable von Mises stress values from the implants and abutments, as well as comparable maximum and minimum principal stress values from the cortical and trabecular bones. The PEEK crown showed the lowest stress (46.89 MPa) in the cervical region. The prosthetic screws and implants exhibited the highest von Mises stress among the models. The lithium disilicate crown model had approximately 9.5 times more cycles to fatique values for implants and 1.7 times more cycles to fatique values for abutments than for the lowest ones. Conclusions With the promise of at least ten years of clinical success and favorable stress distributions in implants and prosthetic components, clinicians can suggest using an implant-supported lithium disilicate crown with a titanium base abutment.

Soft actuators are one of the most promising technological advancements with potential solutions to diverse fields’ day‐to‐day challenges. Soft actuators derived from hydrogel materials possess unique features such as flexibility, responsiveness to stimuli, and intricate deformations, making them ideal for soft robotics, artificial muscles, and biomedical applications. This review provides an overview of material composition and design techniques for hydrogel actuators, exploring 3D printing, photopolymerization, cross‐linking, and microfabrication methods for improved actuation. It examines applications of hydrogel actuators in biomedical, soft robotics, bioinspired systems, microfluidics, lab‐on‐a‐chip devices, and environmental, and energy systems. Finally, it discusses challenges, opportunities, advancements, and regulatory aspects related to hydrogel actuators. [ABSTRACT FROM AUTHOR]

Atmospheric water harvesting (AWH) is considered one of the promising technologies to alleviate the uneven‐distribution of water resources and water scarcity in arid regions of the world. Hydrogel‐based AWH materials are currently attracting increasing attention due to their low cost, high energy efficiency and simple preparation. However, there is a knowledge gap in the screening of hydrogel‐based AWH materials in terms of structure‐property relationships, which may increase the cost of trial and error in research and fabrication. In this study, we synthesised a variety of hydrogel‐based AWH materials, characterized their physochemcial properties visualized the electrostatic potential of polymer chains, and ultimately established the structure‐property‐application relationships of polymeric AWH materials. Poly(2‐acrylamido‐2‐methyl‐1‐propanesulfonic acid) (PAMPS) hydrogel is able to achieve an excellent water adsorption capacity of 0.62 g g−1 and a high water desorption efficiency of more than 90 % in relatively low‐moderate humidity environments, which is regarded as one of the polymer materials with potential for future AWH applications. [ABSTRACT FROM AUTHOR]

The proper selection and planning of building materials are crucial tasks in architectural design, as they fundamentally impact the functioning of the structure. In traditional design processes, this information is recorded in text form, typically using word processing software. However, this approach hinders the integration with modern, data-driven design methods and is incompatible with the increasingly popular building information modeling (BIM) processes. To address this, two new methods have been developed: one database-like method in the form of an Excel spreadsheet and the other as a dedicated web application. This article introduces and compares these methods based on pilot projects conducted by university students and an expert. Based on the results of the study conducted among students and expert, the database-like method proves to be the fastest. For students, creating a composite structure took an average of 14–20 min, while for experts, it took an average of 1.2 min. According to the evaluation of participants, the traditional method does not facilitate automatic communication with BIM, while both the database and web solutions promote it. The web-based solution, with its dedicated layout and functionality, offers additional advantages in this regard. The research underscores the importance of structured data in BIM and proposes new methods to streamline composite documentation processes during the design phase. [ABSTRACT FROM AUTHOR]

This paper overviews the use of several waste materials for the construction and reconstruction of surface courses of asphalt pavements in the framework of sustainable perspectives that are adopted in pavement engineering. Based on a relevant literature search, the most commonly investigated alternative materials include waste plastic, crumb rubber, waste glass, steel slag, and Reclaimed Asphalt Pavement (RAP). Although recycling in pavement engineering is not a novelty, the strict performance requirements of the surface layers required to support a distress-resistant behavior possess continuous research challenges about the mechanical behavioral parameters, such as fatigue, rutting, moisture damage, and serviceability requirements, such as skid resistance. While studies in a laboratory environment mainly dominate, the importance of performance observations of real structures in the field is also pinpointed in an effort to provide a comprehensive overview of the so far knowledge status. Thereafter, this paper discusses peculiar issues and criteria for waste material selection that should balance performance requirements, local availabilities, and potential legislation concerns, thereby maximizing the economic or environmental advantages. [ABSTRACT FROM AUTHOR]

For any type of existing vehicle, one of the most important systems in its structure is the braking system. It is also the main safety element, which stops the vehicle by converting kinetic energy into heat. For constructive reasons and thermal efficiency, ventilated discs are the most widespread and used in industry, therefore, they will also be used in this scientific paper. Ventilated discs are often used to automobile application because of their higher heat dissipation. The purpose of this work is to create a thermally efficient design for ventilated brake discs by adopting two different designs from a constructive point of view. A special importance was also for the brake disc material, initially a semi-metallic material was chosen, being the most used for discs, later the ceramic material was also chosen, which has improved thermal properties. The design variant for the brake disc, to which the disc material and the thermal shield are added, lead to a significant improvement from a thermal point of view, which was also the main objective of this work. Ultimately, this study underscores the pivotal role of innovative design strategies and material selection in advancing the thermal efficiency of ventilated brake discs, thus contributing to the broader landscape of automotive safety and performance engineering. [ABSTRACT FROM AUTHOR]

In an increasingly competitive and digital industrial environment, the optimization of structures is a key point not only to reduce costs but also to reduce the consumption of natural resources. To this end, different approaches have emerged throughout history based on the tools available at the time. With the current rise of artificial intelligence and the concept of machine learning, revolutionary ideas are emerging that allow an optimal dimensioning of structures in record time. This work presents the use of variational autoencoders and mixed-variable solvers as a proposal for structural optimization and material selection. It has expanded upon previous research by advancing in three directions: (1) incorporating more material attributes, particularly relevant for environmental considerations; (2) analyzing in more detail aspects of VAEs such as the dimensionality of the latent space; and (3) a two-step hybrid approach to select the optimal candidate: preliminary filtering with VAE and final design via mixed-variable model. Various examples demonstrate the applicability of the proposed method. [ABSTRACT FROM AUTHOR]

Hydrocarbons, water, carbon dioxide, hydrogen sulfide, chloride, high temperatures and pressures are all involved in the oil and gas production. Thus, corrosion, particularly sulfide stress cracking (SSC), poses a great threat to the integrity of well components such as tubing, casing, packer, and wellhead assembly. Sometimes, SSC can lead to catastrophic failures and must be addressed due to operational security and environmental concerns. Localized corrosion, including SSC can be reduced greatly with the appropriate material selection and optimization of critical operational parameters. The material selection is performed according to service environments vis-a-vis mechanical/ metallurgical attributes of the alloys as prescribed in standards such as API 5CT and ANSI/NACE MR0175/ISO 15156. Currently, corrosion-resistant alloys (CRAs) such as martensitic and duplex stainless steels, nickel, titanium and other precipitation hardened alloys are available and used in oil and gas industries because of their superior mechanical and corrosion properties. Owing to the operating environmental reasons, designer often opt for more expensive CRAs as compared to relatively less expensive materials which fall close to the performance boundary of materials selection criteria, thereby increasing overall cost of crude oil production. Thus, there is a paramount requirement to ascertain the candidate materials appropriately without bearing the cost penalties of over-specifications or the performance shortfalls of under-specified alloys when new fields are discovered. In this paper the application domains of 13Cr martensitic stainless steels are reviewed vis-a-vis limits prescribed in ANSI/NACE MR0175/ISO 15156 standard. The paper will aid in the selection of cost-effective materials for oil and gas production when temperature, pressure, hydrogen sulfide concentration, pH, and salinity vary in different directions and cannot be well defined within standard limits. [ABSTRACT FROM AUTHOR]

This paper presents a comprehensive approach to optimizing furniture design processes and facilitating wood identification through the development of a mobile application. The application is designed to provide users with intuitive tools and resources for informed decisionmaking in furniture design and wood selection. The first component of the mobile application focuses on optimizing furniture design through furniture size and quality consideration. This encompasses the creation of an intuitive user interface that enables users to specify their furniture design preferences, including material selection criteria. A comprehensive wood database is meticulously curated, furnishing users with comprehensive details on wood sizes, qualities, and thicknesses, thereby aiding in material selection and waste reduction initiatives. Algorithms are employed to recommend optimal wood sizes, considering factors such as material selection, waste reduction, and cost analysis. Visual representation tools are included, allowing users to preview furniture designs with different wood options, facilitating informed decisionmaking. Furthermore, feedback mechanisms have been integrated to enable users to provide feedback on recommended wood sizes and qualities, thereby facilitating continuous enhancement and refinement of recommendations. The second component aims to identify the type of wood by its appearance. Image processing features have been developed to precisely extract visual characteristics from wood sample images, thereby aiding in the identification of wood species. Machine learning models are trained to classify wood species based on visual characteristics obtained from images, thereby enhancing the precision of identification. User interaction tools have been designed to ensure ease of use and accessibility for users in capturing and submitting wood sample images. Within the application, educational resources and materials are provided to help users learn about different wood species, aiding their understanding and selection process. [ABSTRACT FROM AUTHOR]

The yarn selection is an essential step in the manufacturing of brocade. The objective of the research paper is the selection of the best yarn for manufacturing handloom Varanasi brocade. In this research paper, the nine natural fibers (Cotton, Kapok, Hemp, Jute, Palm, Pineapple, Bamboo, Sisal, and Flax) and their properties (Cost, Availability, Comfort, Durability, Texture, color, luster, Ease of use and social values) are considered. This study was conducted in two stages. In first stage, a draft questionnaire was created by considering previous research papers and informal consultation with Analytical hierarchy process (AHP) professionals. It was then tested with seven respondents. In the second stage, the questionnaire was circulated to the 135 consumers. An analytic hierarchy process (AHP) approach was utilized to determine the suitable material through a customer survey to select the best yarn for the furnishing and upholstery industry in Varanasi. The results of the study showed that the customers have given more weight to the availability, comfort and color criteria of handloom products, whereas the weight of the cost was less compared to all other criteria. From the overall weight matrix, the pine apple yarn was ranked as the best yarn for the manufacturing of the Banaras brocade, whereas flax was ranked last. The study was only focused on the selection of natural yarns for Varanasi brocade, and the data were collected only from the handloom customers who prefer offline shopping. It does not consider online customers. Therefore, future research should include the other types of yarns and online customers for the research study. The input of the customers will be helpful for the Varanasi handloom product manufacturers to understand customers' requirements, and it will help to improve sales performance. [ABSTRACT FROM AUTHOR]

The increasing diversity of materials creates many possibilities and constraints that designers have to consider when selecting materials for projects. While the literature has investigated materials selection in engineering, product, and architectural design, knowledge is still lacking in interior design. Accordingly, this study focused on interior finishing materials with three objectives: (1) explore the determinants of materials selection in interior design, and within the residential design context, (2) identify designers' finishing material preferences and selection criteria for floors, walls, and ceilings; (3) investigate designers' criteria prioritizations while selecting materials. For this we conducted one-to-one interviews with architects and interior designers specializing in residential spaces. We first explored their material selection considerations in general. Second, we documented their material designations in residential project entry halls they had designed along with their selection criteria. Third, we presented an entry hall of a residential space for them to choose the materials while we questioned them about their materials selection priorities. The results reveal that the main determinants of materials selection include material-related, project-related, and designer-related factors. Moreover, materials choices and selection criteria vary between surfaces in space. Finally, the designers give the most priority to sensorial properties and the least to ecological properties. These findings expand our knowledge about materials in interior design, enhance the knowledge base for materials education, and have implications for designers and manufacturers regarding selecting and designing finishing materials. [ABSTRACT FROM AUTHOR]

Manifold aspects, such as the booming market for superior quality food items with increased shelf life and the escalating concern to mitigate plastic trash due to plastic packaging have motivated researchers and food industrialists to explore sustainable eco-friendly packaging solutions extensively. Biodegradable polymers are being rigorously investigated to replace conventional plastics that are toxic, non-biodegradable, and detrimental to the marine ecosystem. The scientific methodology for the prudent selection of biodegradable polymer among the frequently used biopolymers for food packaging is being reported here. The data were extracted from the available literature. A hybrid multi-criteria decision-making framework has been developed to address the problem of material selection owing to the multiple conflicting criteria involved. Assignment of equal weights to primary criteria was selected to establish the criteria weights. Different decision-making techniques (weighted sum method (WSM), weighted product method (WPM), weighted aggregated sum product assessment method (WASPAS), and technique for order of preference by similarity to ideal solution (TOPSIS)) were used for the comparative analysis. Thereon, the different ranks obtained for each alternative were aggregated using the degree of membership technique. The robustness of the solution was checked using sensitivity analysis which was conducted by varying weights of importance using the entropy method, the CRITIC method, and the equal weights to secondary criteria. The analysis reported polylactic acid (PLA) as the most reliable polymer for food packaging applications. The sensitivity analysis concluded that the solution was without prejudice, and water vapor permeation rating was the most critical decision criterion in deciding the optimal polymer. [ABSTRACT FROM AUTHOR]

Understanding the erosion characteristics of different pipe materials is of paramount importance in the field of pipeline transportation due to its critical role in maintaining operational efficiency and safety. However, erosion caused by entrained particles during fluid flows poses a significant challenge to pipeline integrity. This study employs Computational Fluid Dynamics (CFD) to comprehensively analyze and compare the erosion behaviors of stainless steel XS80S and steel XS80 pipes with 90° elbows. The investigation focuses on turbulent oil and sand particle transportation conditions, enabling the prediction of erosion rate distribution and particle trajectories, particularly within the elbow region. The results highlight the superior erosion resistance of stainless steel XS80S over steel XS80 across various simulation models. The study underscores the significance of material selection in combating erosion and enhancing pipeline integrity. The XS80S pipes performed better than the XS80 Pipes. The maximum Dpm Erosion Rate Finnie model for the XS80S and XS80 pipes were 8.62 E-25 mm3 kg-1 and 9.17 E-25 mm3 kg-1, respectively; for the McLaury model they were 2.94E-24 mm3 kg-1 and 3.10E-24 mm3 kg-1, respectively; for the Oka model they were 5.68E-26 mm3 kg-1 and 6.75E-26 mm3 kg-1, respectively. The maximum Dpm Accretion Rate for the XS80S and XS80 pipes were 2.01E-17 mm3 kg-1 and 2.06E-17 mm3 kg-1, respectively. Furthermore, the investigation sheds light on the vulnerabilities of the elbow region within pipelines, providing insights into targeted design modifications and maintenance protocols. This research advances the understanding of erosion mechanisms, fluid dynamics, and material performance, offering actionable insights for pipeline industry stakeholders. The findings lay the groundwork for future research avenues and contribute to the evolution of corrosion management practices. [ABSTRACT FROM AUTHOR]

This paper aims to investigate the corrosion behaviour of heat-treated standard duplex stainless steel (UNS S32205) in the recovery of bitumen from Nigerian-rich tar sand, using sodium hydroxide (NaOH) as the process solution. Appropriate material family needs to be identified for the exploitation of tar sand resources to ensure sustainable extraction of bitumen. UNS S32205 offers exceptional mechanical properties and excellent corrosion resistance which makes it a great material choice for demanding applications, including offshore platforms and construction projects. Samples of UNS 32205 were heat-treated and immersed in the digested tar sand, maintaining a process temperature of 90°C. The microstructure of the corrosion coupons was studied using SEM/EDS (Scanning Electron Microscope/Energy Dispersive Spectroscope), and the corrosion rate of the samples was derived using gravimetric technique following ASTM G31 standard. The SEM micrographs indicated varying degrees of pits associated with the passivity of UNS 32205 and an imbalance between its ferrite and austenite phases due to the presence of secondary precipitates formed during heat treatment.The normalized sample, having a corrosion rate of 0.053 mm/year, exhibited the best corrosion resistance, followed by oil quenching (0.054 mm/year), then annealing (0.076 mm/year), and water quenching (0.077 mm/year), where they all showed improved corrosion resistance over the as-received sample having a corrosion rate of 0.078 mm/year.

License plates to uniquely identify vehicles mainly use aluminum as the base material. Currently, there is no distinction of different use cases of license plates, such as short-time usage for test drive and transportation purposes that do not need such long-lasting materials not only from cost but also from sustainability perspectives. This paper presents a methodology to select the best material for different use cases under the holistic consideration of specifically defined criteria as to material properties, sustainability aspects, and supply chain implications. We show that there are several candidate materials for different use cases that stick out by changing the importance of these numerous criteria. In addition, the paper delves deeper into the sustainability aspect by means of a comprehensive System Dynamics model. We show that a scenario in which the company picks up used license plates by relying on a logistics service provider to get them delivered to an external recycling service provider yields the best results.

ABSTRACTThe construction industry is confronted by resource constraints. It affects the initial costs and environment that requires resource and method optimization. The objective of the research is to design a mathematical MCDM model that would enable to select economically and ecologically suitable building material. To achieve this, the researcher designed, evaluated, and selected the suitable concrete grade using a combined mathematical MCDM. The objective sampling technique is used in Addis Ababa to collect samples of high-rise structures and materials. The study used objective-weighed MCDM and fuzzy-AHP to create specific concrete grades. The amount of the objective was fitted by 95% sensitivity analysis cost and quantity of concrete using a combination of MCDM, linear programming, and Monte Carlo simulation. The result demonstrates that, although the unit cost of concrete increased as strength grew, the project’s overall cost was reduced by reducing the project quantities. It will also add more space with environmentally friendly, sustainable structures. In conclusion, the integrated mathematical MCDM model is a helpful tool for selecting urban structure cost-effective materials

AbstractIn ship construction, material costs constitute a substantial portion of the overall expenses. With the surging steel prices, the shipbuilding industry faces a pressing challenge. To counterbalance this issue, optimizing the structural components of ships has emerged as a viable solution. Genetic Algorithm (GA) methods, known for their application in structural optimization, have demonstrated their potential. However, the protracted computational time associated with GA remains a limiting factor. This research introduces a novel approach by merging GA with Finite Element Method (FEM) for optimizing plate sizes, resulting in a hybrid GA system. Moreover, the study incorporates sensitivity analysis (SA) due to its proven efficacy in enhancing optimization processes involving multiple variables. The SA component investigates plate interrelationships and effectively clusters them. After this grouping, the hybrid GA executes parallel optimization of plates that influence each other under tension. By integrating SA, the optimization process becomes faster and more time-efficient, while preserving optimal manufacturing costs. Remarkably, this methodology culminates in a substantial reduction in computational time when contrasted with the hybrid GA approach devoid of SA, all the while maintaining a parallel manufacturing cost trajectory. In conclusion, this study presents an innovative hybrid GA approach, supplemented with SA, as an effective strategy for mitigating the escalating steel costs in shipbuilding. The amalgamation of GA, FEM and SA synergistically simplifies the optimization process, ensuring optimal results in a faster way.

Material selection is influential in product design, manufacturing, and marketing. Appropriate material selection maximizes the performance of a product while minimizing its cost, whereas inappropriate material selection creates devastating results such as low performance, low quality, and high cost. Therefore, it is crucial how to choose the most suitable material. Unlike other studies, this study presents an ensemble multi-attribute decision-making approach for material selection. The approach involves four weighting methods—criteria importance through intercriteria correlation, Entropy, the method based on the removal effects of criteria, and statistical variance, five ranking methods—additive ratio assessment, combined compromise solution, multi-attributive border approximation area comparison, range of value, and the technique for order performance by similarity to the ideal solution, Spearman's correlation coefficients, and the Copeland method. Three different problems are considered to show the applicability of the proposed method and to reveal a comprehensive analysis. The results of each problem show valuable implications. The results of the ranking methods are sensitive to attribute weights. No ranking method alone can assure dependable selection for a given problem. Overall, the results reveal the importance of using multiple weighting and ranking methods and the superiority of the proposed integrated approach. [ABSTRACT FROM AUTHOR]

Determining weights for criteria is an extremely crucial step in the process of selecting an option based on multiple criteria, also known as Multi-Criteria Decision Making (MCDM). This article presents the combination of five objective weighting methods for criteria with three MCDM methods in the context of material selection. The five objective weighting methods considered are Entropy, MEREC (Method based on the Removal Effects of Criteria), LOPCOW (Logarithmic Percentage Change-driven Objective Weighting), CRITIC (Criteria Importance Through Intercriteria Correlation), and MEAN. The three MCDM methods employed are MARA (Magnitude of the Area for the Ranking of Alternatives), RAM (Root Assessment Method), and PIV (Proximity Indexed Value). Material selection investigations were conducted in three different cases, including lubricant selection for two-stroke engines, material selection for manufacturing screw shafts, and material selection for manufacturing gears. The Spearman's rank correlation coefficient was calculated to assess the stability of ranking the alternatives using different MCDM methods. The combinations of objective weighting methods and MCDM methods were evaluated based on factors such as consistency in identifying the best material type, range, average value, and median of each set of Spearman's rank correlation coefficients. Two significant findings were identified. First, the weights of criteria calculated using LOPCOW method appear to be inversely related to those calculated using the Entropy method. Second, among the three MCDM methods used, MARA was identified as the most suitable for lubricant selection for two-stroke engines, RAM was found to be the most suitable for material selection for screw shafts and gears. The best material type in each case was also determined. [ABSTRACT FROM AUTHOR]

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A delivery system can enhance the solubility, stability and bioavailability of bioactive substances by encapsu-lating them and thus make it convenient application in the food, medicine, cosmetics and other fields. Emulsification solvent evaporation is a common method to prepare delivery carriers of active substances, its characteristics including use of mild conditions, ease of use and scale-up, lower residual solvent and so on. After introduction of emulsification solvent evaporation method, this paper summarizes the influence of material selection and preparation process on the delivery carriers, as well as the research progress on the application of this method in the delivery system, in order to promote further research and practical application of emulsification solvent evaporation method. [ABSTRACT FROM AUTHOR]

This paper focuses on the issues of sour water corrosion, CO2 corrosion, wet H2S corrosion, chloride ion corrosion, and stainless steel chloride stress corrosion cracking in gasification-scrubbing system of coal to hydrogen unit. The on-site corrosion monitoring results show that 15CrMo and 14CrlMo are belong to corrosion-resistant materials, while 06Crl3, S30403, S31603, and S22053 are fully corrosion-resistant materials. The laboratory corrosion evaluation results show that 15CrMo belongs to corrosion-resistant materials at less than 200 °C and non corrosion-resistant materials at not less than 200 °C; 06Crl3 is a good corrosion-resistant material at less than 250 °C, and a corrosion-resistant materials at not less than 250 °C; S30403, S31603, and S22053 are fully corrosion-resistant materials; chloride ions have a promoting effect on the corrosion of Q245R and 15CrMo. Based on the above researches, combined with the actual operation of the unit and engineering experience, a recommended plan for equipment and pipeline material selection has been developed, and corrosion control strategies have been proposed. [ABSTRACT FROM AUTHOR]

In ship construction, material costs constitute a substantial portion of the overall expenses. With the surging steel prices, the shipbuilding industry faces a pressing challenge. To counterbalance this issue, optimizing the structural components of ships has emerged as a viable solution. Genetic Algorithm (GA) methods, known for their application in structural optimization, have demonstrated their potential. However, the protracted computational time associated with GA remains a limiting factor. This research introduces a novel approach by merging GA with Finite Element Method (FEM) for optimizing plate sizes, resulting in a hybrid GA system. Moreover, the study incorporates sensitivity analysis (SA) due to its proven efficacy in enhancing optimization processes involving multiple variables. The SA component investigates plate interrelationships and effectively clusters them. After this grouping, the hybrid GA executes parallel optimization of plates that influence each other under tension. By integrating SA, the optimization process becomes faster and more time-efficient, while preserving optimal manufacturing costs. Remarkably, this methodology culminates in a substantial reduction in computational time when contrasted with the hybrid GA approach devoid of SA, all the while maintaining a parallel manufacturing cost trajectory. In conclusion, this study presents an innovative hybrid GA approach, supplemented with SA, as an effective strategy for mitigating the escalating steel costs in shipbuilding. The amalgamation of GA, FEM and SA synergistically simplifies the optimization process, ensuring optimal results in a faster way. [ABSTRACT FROM AUTHOR]

Material selection in the engineering design process is a challenging process because there are many materials and many contradictory features that must be together. The plough is the most important and basic tool of tillage. Large abrasions, cracks, and even sudden breaks can occur in the plough that cultivates the soil. For this reason, the material chosen to produce the ploughshares is extremely important. In this study, first of all, the criteria that are important in the selection of ploughshares iron were determined, and the criteria were weighted with the Interval Shannon Entropy method. Material preference ranking was made using "the Fuzzy Technique for Order Preference by Similarity to Ideal Solution" (FTOPSIS) technique. According to the study results, the order of the ploughshare’s material selection criteria is, respectively, hardness, wear percentage, toughness, tensile stress, thermal conductivity, and cost. As a result of the selection made using the FTOPSIS method; It has been determined that 33MnCrB5(1.7185) should be preferred in the first place among the candidate materials, and then the order of preference should be 51CrV4(1.8159), 60SiMn5(SAE9262), 41CrMo4 (1.7225QT-4140), respectively. To measure the sensitivity of the results, sensitivity analysis was conducted at α=0.1, 0.5, and 0.9 levels. [ABSTRACT FROM AUTHOR]

This study investigates EFL university lecturers' challenges when selecting resources to facilitate students' self-regulation. Using a mixed-method design with 89 participants from Thai universities in this research sheds light on lecturers' difficulties, such as time constraints and limited access to reliable resources. It underscores the importance of considering diverse perspectives and practical strategies, such as adapting existing materials and involving students in the selection process. Furthermore, it highlights the direct impact of material choices on students' self-regulation outcomes. The study provides strategies to enhance self-regulation among EFL university students and suggests improvements for resource selection procedures. Despite its limitations, this research contributes valuable insights and pedagogical recommendations. Future avenues of study may explore the influence of digital learning resources, teacher-student collaboration in material selection, and cross-cultural perspectives on self-regulation and material choice. [ABSTRACT FROM AUTHOR]

Although the working principles of capillary barrier effects (CBEs) have been well explained based on unsaturated soil mechanics, the selection of materials for engineering structures with CBEs mostly relies on designers' experience or previously reported data, largely due to the lack of understanding of the microscale behavior of CBEs. This study explores the impact of pore sizes on CBEs based on pore network modeling. The results indicate that the pore size variability in either the fine or coarse layer has a remarkable influence on CBEs, with the latter having a dominating influence. A larger coarse-to-fine mean pore size ratio results in more effective CBEs. In addition to selecting materials with more uniform pore sizes, the coarse-to-fine mean pore size ratio is recommended to be >6 (median particle size ratio of 30) to ensure the performance of CBEs. [ABSTRACT FROM AUTHOR]

Abstract Compressed air energy storage (CAES) is attracting attention as one of large‐scale renewable energy storage systems. Its gas storage chamber is one of key components for its success. A successful utilization of an abandoned coalmine roadway depends on the stability of the gas storage chamber. The chamber is a multilayer structure and the redistribution of the stress and displacement in each layer is critical to the chamber stability. So far, this redistribution mechanism under any lateral pressure coefficient and internal air pressure has been unclear and thus a quick and easy evaluation on the CAES chamber stability becomes difficult. In this study, the redistributions of stress and displacement in each layer are analytically solved based on complex variable function theory. First, the stress and displacement in three CAES multilayer structures are obtained under any lateral pressure coefficient and internal air pressure. Then, a comprehensive parameter b1 is obtained to describe the redistribution of stress and displacement in rock mass, lining layer, and grout layer. Its linkage with lateral pressure coefficient, internal air pressure, and material properties is analytically expressed. Thirdly, an analytical expression is obtained for the influence range of internal air pressure on chamber stress. Finally, the role and selection of lining and grouting layers are explored at different lateral pressure coefficient and internal air pressure. It is found that the CAES chamber stability can be effectively and quickly evaluated by these analytical solutions and comprehensive parameters and enhanced by a material with low bulk modulus but high shear modulus.

Abstract Key message The application of material selection principles uncovered eight possible alternative tree species (two deciduous and six coniferous species) to substitute Norway spruce (Picea abies (L.) H. Karst.) and potentially prevent economic loss in European forest. Context Climate change is a major challenge for the Central European forest and timber industry. Increasing biotic (e.g. beetle damage) and abiotic (e.g. drought) calamities have led to major losses in forest value, especially on Norway spruce (Picea abies (L.) H. Karst.) stands. Therefore, a transition to climate change adapted forest management is necessary. Concurrently, neophytes (e.g. tree of heaven (Ailanthus altissima (Mill.) Swingle), Douglas fir (Pseudotsuga menziesii (Mirbel) Franco), grand fir (Abies grandis (Douglas ex D. Don) Lindl.) and Paulownia (Paulownia tomentosa (Thunb.) Steud.)) are increasing their dominance in forest communities and causing additional adaption of the forest ecosystem. Both factors will lead to significant changes in wood species distributions in Central European forests, mainly at the expanse of Norway spruce, over the next decades. Aims Choosing the “right” tree species for afforestation will become ever more complex and will require a holistic approach that combines forestry and technological aspects alike. Therefore, this review presents a selection approach based on available wood material data from literature and the material selection principles proposed by M. Ashby with the aim to identify suitable alternatives for Norway spruce (Picea abies (L.) H. Karst.) and further concisely assess their silvicultural relevance. Methods For this wood species comparison and selection process, dry and raw density, bending strength and modulus of elasticity were chosen as key properties. Beam- and plate-like components subjected to a bending load were chosen as representative use cases. Results European birch (Betula spp.), grand fir (Abies grandis (Douglas ex D. Don) Lindl.) and silver fir (Abies alba Mill.) were identified as suitable alternatives for Norway spruce (Picea abies (L.) H. Karst.) from a technological as well as silvicultural point of view. In addition, Paulownia (Paulownia tomentosa (Thunb.) Steud.), Sitka spruce (Picea sitchensis (Bong.) Carrière), yellow pine (Pinus strobus L.), western red cedar (Thuja plicata Donn ex D. Don in Lambert) and loblolly pine (Pinus taeda L.) offer a technological advantage but currently lack relevance in the forest sector. Conclusion The proposed selection process offers an evaluation of technical performance, and in combination with an assessment of the silvicultural relevance, it will be possible to optimize the wood-supply chain and prevent future economic loss of Central European forests.