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Floor drains remove surface fluids and provide a physical barrier between building drainage and the sewer. Their function minimises waterborne contaminant impact on connecting drainage. Bacteria are known to thrive in drainage systems, and material selection, drain design, installation specification and maintenance all affect the potential for bacterial harbourage viability. Furthermore, the use of gullies or channels impacts ergonomic, economic and hydraulic considerations. Channel system hydraulic capacity must be assessed using a steady non-uniform flow formula, the use of which highlights that fluid velocities will fall far short of ‘self-cleansing’ velocity. Development areas include the use of passive or automated backflow prevention valves in sub-surface drainage. Whilst slip resistance and fire protection mechanisms can be incorporated in gratings and gully bodies respectively.

A novel planar dielectric polarizer made of a low-profile high dielectric constant material is proposed. Two anisotropic anti-reflection layers are used on both sides to provide impedance transformation and anisotropy simultaneously. The proposed design uses a high-dielectric-constant material to reduce the overall thickness without severe reflections. The unit cells of the middle layer and the anti-reflection layer use separate periods for better adapting to the fabrication limitation. A polarizer prototype centered at 24 GHz is designed, fabricated, and measured. The prototype is 3D-printed by commercial fused-deposition-modeling (FDM) technology using a material with a dielectric constant of 10. Experiments show the prototype has a 25% operating bandwidth and a thickness of 0.52λ0 (λ0 is the wavelength in the free space). The design methodology widens the choice for material selection and reduces the dimensions of the dielectric polarizer.

This work proposes a material selection decision-making method for multi-material lightweight body driven by performance to achieve that the right materials are used for the correct positions of the automotive body. The internal relationship between performance and mass, cross-sectional shape, wall thickness parameters, and material properties of a thin-walled structure is studied. The lightweight material indices driven by performance are then established. The lightweight material indices and material price are taken as the decision-making criteria for the material selection of automotive body components. A hybrid weighting method integrated with the analytic hierarchy process, fuzzy analytic hierarchy process, and quality function deployment is proposed. The difficulty of quantitatively evaluating the performance requirements of different components of the body is solved using the proposed weighting method combined with the numerical analytical results of the component performance under multiple operating conditions of the automotive body. Then, the weight of the decision-making criteria for material selection is calculated. Grey relational analysis is used to make multicriteria decision-making on a variety of candidate materials to select the best material for body components. After the lightweight material selection of the front longitudinal beam of the automotive body, the frontal collision safety performance of the body is effectively improved, and the mass of the front longitudinal beam is reduced by 45%. Material selection result of the front longitudinal beam indicates that the proposed material selection decision-making method can effectively achieve the fast material selection of components in different positions of the body.

The high-energy photon source (HEPS) is the first fourth-generation light source under construction in China. It is designed to operate at an average current of 200 mA stored beam current with a top-up model at 6 GeV energy. Considering the linac radiation shielding design, a suitable beam loss scenario, optimized thickness for the bulk shielding and detailed structure design for dumps should be proposed. In this paper, the beam loss scenarios were determined and categorized as normal; the dose limits were presented; using these scenarios and the dose limits, the thickness of the linac tunnel was calculated and detailed designs of the main beam dumps were established. The material selection and size setting of the low-power electron beam dump were discussed. The Monte Carlo code is a good choice to simulate the radiation analysis. And the iSHIELD11 was used to verify the simulation calculations. The designs of the linac bulk shield and dumps satisfied the requirements of radiation protection.

Material selection plays an essential role in environmental product performances; however, choice and comparison between different materials' environmental features are not trivial for designers. Academic and grey literature reviews were used to provide an overview of the main types of software, using a life cycle approach, supporting material selection decisions since the early design stages, highlighting pros and cons of the different tools from a designer's perspective. Three main typologies of software emerged from the study, defined by different usability and completeness degrees. Obstacles and opportunities were noted on four main aspects which influence the choice of the most sustainable material: on the educational level, on the analysis level, on the material selection level, and on a system level. Tools for in depth LCA can be used for material selection; although difficult for designers to use, these software are essential to create a more critical awareness for the application of both conventional and new materials. Simplified LCA Tools with limited impact categories, and simplified tools explicitly dedicated to material selection from a life cycle thinking perspective, better respond to the usability needs of designers, who must, however, consider the limits of precision of these tools, combining their use with a life cycle design approach and applying ecodesign strategies. To date, little effort has been made to integrate such tools properly in the design practice; therefore, multidisciplinarity between LCA experts and designers is strongly recommended, especially to avoid misleading aspects in assessing the growing number of materials that tend to be considered a key for sustainable innovation.

This paper presents a methodology that integrates the semi-empirical corrosion models with probabilistic analysis to study steel structural failure behavior considering material and parametric uncertainties. The semi-empirical models are used to assess the asset’s susceptibility, system degradation rate, and defect growth over time under harsh corrosive environment. The developed model is translated into a limit state function in a probabilistic framework to define the asset’s safe operating envelope. The probabilistic framework is simulated considering the variations in the material properties of steel grades, corrosion response parameters, and types of susceptibility models. The variabilities in the ultimate tensile strength, operating pressure, and wall thickness exhibit the highest contributions to pipeline failure behavior in a harsh offshore environment. It is also observed that the failure probability of the pipeline increases with an increase in the coefficient of variation at the lower bound of failure, while it decreases at the upper bound of failure. The coefficient of variation for the tensile strength shows a 32.2% (the highest) impact on the limit state function performance as the year of exposure progresses. The proposed approach offers a systematic framework for an appropriate material selection and risk-based integrity management strategy for offshore structures, including pipelines.

Nonlinear Transmission Lines (NLTLs) are a new technique for radio frequency (RF) generation. A loaded ferrite NLTL, known as a gyromagnetic line, uses a solenoid to provide an external magnetic bias. In space applications, specifically in satellites, the replacement of these solenoids by permanent magnets is desirable, eliminating the need for a DC current source, and reducing the weight and the effective cost of the launch. This work investigated and selected permanent magnets for this application, and then computationally modeled the magnet assembly to analyze the resulting magnetic field generated and obtained a uniform field region to meet the NLTL operating specifications. For this, we employed selection charts for the proper choice of material to use in an arrangement of magnets simulated by the electromagnetic software CST Microwave Studio . Magnetic fields with uniformity variations of less than 6% and 23% in regions extended over 18.5 cm and 58.8 cm, corresponding to line lengths of 26.6 cm and 68.0 cm, respectively, were achieved in simulations.

In the last decades, the amount of space debris has increased substantially and it is now considered a critical issue by the space community. Small spacecraft in Low Earth Orbit usually rely on passive strategies to ablate once their active life has ended: they re-enter atmosphere and demise due to the thermal degradation of their components. Even if small satellites are deemed systems with limited casualty risk, some critical components are rather difficult to demise, and the ongoing commercial growth of the small satellite sector poses serious concerns due to the elevated number of re-entry events expected in the upcoming years. Currently, the majority of risk analysis tools are mainly oriented on demisability improvements and, among several available strategies, the substitution of critical materials with more demisable ones is extremely effective. Although widely accepted, this operation may potentially reduce the performance of the component if not accurately designed. For this reason, a detailed materials selection, based on demisability and performance as concurrent objectives to optimize, is here presented. The addition of a performance index in the risk analysis can substantially refine potential solutions and their impact. The proposed approach is general and scalable, as it can be extended to different categories of sub-systems and satellite sizes. We have investigated the case of reaction wheels, one of the most critical component in small satellites. The results indicate how novel materials candidates can sensibly contribute to improve demisability of the component, without reducing its performance level. Furthermore, our method can be combined with common risk analysis tools, representing a valuable asset for the design of demisabile spacecraft and for the sustainable use of space.

With sustainable design as a vital strategical component for companies competing on the market today, many companies will need to transition to a use of sustainable and/or renewable materials in th...

Introduzir novos materiais e transformá-los em produtos diferenciados, por meio de processos adequados, é um dos desafios da área de desenvolvimento de produtos. Este estudo detalha o projeto de utensílio doméstico - colher para preparo alimentos - com propostas de substituição dos materiais empregados convencionalmente no mercado, com a premissa de explorar o toque suave e a flexibilidade da forma que os Elastômeros Termoplásticos (TPEs) podem proporcionar. O presente trabalho descreve diferentes tipos de processos industriais de injeção multimateriais, destacando critérios para a seleção adequada do processo. Foi empregada a metodologia de seleção de materiais de Ashby, complementando métodos projetuais de design de Bonsiepe. Foi realizada uma comparação de materiais computadorizada com o software Cambridge Engineering Selector, a fim de comparar propriedades relevantes para a função estrutural e pelas restrições de resistir a temperaturas elevadas, decorrente do uso no processo de cozimento de alimentos. Além disso, foram realizadas análises com o software CAE SolidWorks Plastics, para simular o preenchimento das cavidades do molde com diferentes polímeros, analisando o tempo de preenchimento e resfriamento, pressão, temperatura, cisalhamento e rechupes. Os resultados encontrados com o software CES Selector, permitiram destacar duas possibilidades de seleção focada principalmente na resistência térmica. Os candidatos mais promissores encontrados foram o PA6 para a parte rígida e o TPA para a parte flexível ou PBT para a parte rígida e TPC para a parte flexível. Contudo, a classe de TPEs encontrou dificuldade em substituir o silicone com a mesma performance no critério de temperatura máxima de trabalho. Mesmo assim a combinação PA6 com TPA mostrou-se satisfatória. Já o resultado da simulação do processo de injeção apresentou-se promissor, devido ao bom preenchimento da cavidade. Os resultados indicam que a união do PA6 com o TPA é a melhor escolha, considerando o valor de mercado da resina, o módulo de elasticidade, a energia incorporada, a temperatura de trabalho e o processamento simulado da co-injeção da dupla de materiais.

Cranioplasty materials include metals (ie, titanium); ceramics (ie, hydroxyapatite); polymers (ie, poly-methyl-metha-acrylate [PMMA]); and plastics (ie, polyether ether ketone). This paper aims to review their advantages and drawbacks. No ideal material currently exist, however, titanium implants are universally agreed to have lower infection rates than those reported for hydroxyapatite and PMMA implants; thus justifying their current wide use. These implants can be manufactured conventionally from medical grade titanium alloy Ti64 (titanium-aluminum-vanadium) in the form of plates ranging in thickness from 0.5 to 0.7 mm thick, or following the computer-aided design/manufacture principle. Surface finish of these implants is best achieved by electroplating.

Reducing carbon emissions is the direction various industries will head in the future. Solid wood furniture products that occupy important market shares have high carbon reduction potential. This article briefly describes the carbon footprint of the solid wood furniture production process. In addition, it analyzes the feasible carbon reduction technologies applicable during the design and manufacturing process through the potential emission reduction-oriented approach, ranging from the upstream raw materials to overall power consumption. The primary carbon reduction potential points entail the high efficiency and reuse of primary materials, the reduction of auxiliary materials, and the optimization of solid wood processing based on spraying and dust removal. In this study, the carbon reduction design of solid wood furniture primarily covers the design methods, material selection, structural design, and packaging design. The carbon reduction manufacturing technology was analyzed from a process, equipment, and management aspect. It is hoped that this study can provide a reference for the future strategic design of solid wood furniture companies, which will promote low-carbon development in the wood furniture industry.

Solid Oxide Fuel Cells (SOFCs) are electrochemical devices with solid electrolyte materials that convert chemical energy in fuels into electrical energy. Tubular SOFCs (T-SOFCs) is one of the major SOFC configurations which has the advantages of good thermal conductivity, easy to seal and shorter start-up time. However, challenges remain in effectively collecting the current inside the tubular cells. Developing an efficient, easily applicable and cost-effective collector is imperative. The properties of a desired current collector are to: reflect the fuel cell performance, be able to withstand the fuel cell’s high working temperature environment, protect the fuel cell from damage, simplify the current collector application procedure, expand the contact surface between the tube and the current collector, and save cost. We have designed a current collector and identified the materials for inside tube current collection with desired characteristics such as high temperature tolerance, low electrical resistance, and low cost. The research focused on the effectiveness of the current collector and its durability at various fuel cell operation conditions. The design achieved a peak power density at 0.7V of 0.21W/cm2 at the temperature of 700oC for a conventional tubular SOFC with material set of Ni+8YSZ‖YSZ‖LSM. Comparing to the general metal (nickel, silver) current collectors, the studied material can reduce the cost from hundreds of dollars per yard to $0.13/yard. The paper will discuss the design and the cost-effective material selection of the current collector which provides a potential path for the commercialization of tubular SOFC technology.

The purpose of this study was to develop the design of multifunctional children’s clothing that supports sustainability goals. This paper proposes multifunctional clothing that can be recycled and decomposed at the end of the clothing’s lifespan. In particular, the Eco-fashion design model was adopted in this project. After analyzing fashion consumption and problems in children’s product design, four items of multifunctional children’s clothing were developed. Multifunctional children’s clothing design focuses on material selection, zero-waste techniques, design for disassembly and children’s health. Thus, the minimization of material diversity as well as the application of zero-waste design techniques and multifunctional design guidelines for children’s clothing design can be implemented towards sustainability in order to preserve the environment by selecting recyclable materials, promoting profit and human health concerning multifunctional purposes and international standards for children’s clothing design. The findings can be used in various apparel products to help mitigate problems related to environmental pollution and resource depletion in the apparel industry.

Hermetic sealing microelectronic devices in package become more and more of a challenge for manufacturers due to the complexity of thermal management, getter integration, and material selection and interactions. Such complexity drives the original equipment manufacturer (OEM) to deliver the equipment and technology to meet manufacturers’ requirements. This study has successfully demonstrated that a vacuum reflow technology is able to deliver packages with an excellent hermetic seal. The measured leak rates of these two package types are about two orders of magnitude better than the requirement by Mil-Std 883 method 1014 specification. The result is clear that optimization of the force applied to the lid and package during seal process is essential and the force density of 5 kPa is able to produce a great hermeticity for the two packages under study. A good solder joint strength is essential to deliver a package with hermeticity but is not enough, while a weak joint strength is not possible to achieve hermeticity.

The material selection problem is one of the most important steps in the development process of a part of any subassembly assembly, machine, product, etc. The material selection process needs a systematic and time-consuming approach to choose the optimal material to satisfy the product’s requirements. That is to say, many confronting criteria and possible material types (alternatives) available, makes this problem Multi-Criteria Decision-Making problem (MCDM). This paper shows the applicability of the MCDM methodology in the material selection problem for steam heating plates for the vulcanization process used in the inner tube manufacturing process. Specifically, the criteria weights are obtained by CRITIC (Criteria Importance Through Intercriteria Correlation), ENTROPY and PIPRECIA (Pivot Pairwise Relative Criteria Importance Assessment) methods, while TOPSIS (Technique for the Order Preference by Similarity to Ideal Solution) method has been implemented in this process for evaluation and ranking of the possible alternatives (material types).

This paper focuses on improving the performance of a MEMS technology based variable capacitor for high frequency wireless communication applications. The paper starts with a discussion on the Q factor and methods of improving it. A novel expression for the Q factor of a MEMS capacitor was derived from an equivalent T-line model of the capacitor. Using the derived expression for Q factor and other parameters, Ashby analysis was performed to choose the best materials for the dielectric layer and metal plates. Based on the analysis, the most suitable materials for the dielectric and metal plates were obtained to enhance the performance of the capacitor.

Triplet–triplet annihilation upconversion (TTA-UC) is a process by which a lower energy photon can be upconverted to a higher energy state. The incorporation of TTA-UC materials into solid-state hosts has enabled advances in solar energy and many other applications. The choice of host system is, however, far from trivial and often calls for a careful compromise between characteristics such as high molecular mobility, low oxygen diffusion, and high material stability, factors that often contradict one another. Here, we evaluate these challenges in the context of the state-of-the-art of primarily polymer hosts and the advantages they hold in terms of material selection and tunability of their diffusion or mechanical or thermal properties. We encourage more collaborative research between polymer scientists and photophysicists in order to further optimize the current systems and outline our thoughts for the future direction of the field.

In this article, we thoroughly discuss many aspects of diaphragm-embedded optical fiber sensors covering industrial, robotics and medical applications: from the modeling to field applications, which also include sensor fabrication (such as interferometers, grating-based sensors, intensity variation sensors) in standard and specialty optical fibers, diaphragm and optical fiber materials thermal and mechanical characterizations. The operation limits of the sensors, interrogation techniques and the measurement possibilities that such sensors provide are also discussed. We expect that this review and tutorial provide valuable information regarding the optical fiber sensor approach, material selection and sensor assembly for the development of diaphragm-embedded optical fiber sensors.

High-temperature oxidation is a common failure in high-temperature environments, which widely occur in aircraft engines and aerospace thrusters; as a result, the development of anti-high-temperature oxidation materials has been pursued. Ni-based alloys are a common high-temperature material; however, they are too expensive. High-entropy alloys are alternatives for the anti-oxidation property at high temperatures because of their special structure and properties. The recent achievements of high-temperature oxidation are reviewed in this paper. The high-temperature oxidation environment, temperature, phase structure, alloy elements, and preparation methods of high-entropy alloys are summarized. The reason why high-entropy alloys have anti-oxidation ability at high temperatures is illuminated. Current research, material selection, and application prospects of high-temperature oxidation are introduced.

Material selection is an important step under active planning phase in production planning and control and, so is process selection. Polymers are preferable option for various products due to their desirable properties. Light weight, low cost, corrosion resistant and high strength to weight ratio is few among them. In similar manner injection molding is the most suitable process to be preferred for processing various grades of thermoplastics. The process preferably utilizes a heating unit to take polymers to their injection temperature, a permanent mold with shaped cavity as the shape of the required product along with clamping and cooling provisions. The process is best suitable for mass production of plastic parts and is widely used industrially. The permanent mold used in injection molding process is also referred as plastic mold. These molds must be designed and analyzed before their manufacturing to ensure suitability of the molding with particular plastic material type. This article attempts to ensure suitability of molding plastic wing nuts, an internal threaded component, by injection molding process with polypropylene (PP) and high density poly ethylene (HDPE) material. Modeling of parts is done with UG Nx 9.0 while the flow analysis is performed by Autodesk Mold Flow Adviser 2015. Index Terms: Injection molding, permanent mold, internal threaded component, polypropylene, high density poly ethylene.

Since two decades piezoelectric MEMS resonator research has been making a headway by leaps and bounds in multiple fronts such as micro/nanofabrication techniques, device and system design, monolithic integration, packaging, material engineering, etc. Piezoelectricity based frequency selective resonant tanks are an integral part of radio frequency communication, inertial sensors, infrared sensors, environmental monitoring modules, energy harvesters, etc. To improve the functionality of the aforementioned modules it is cardinal to understand the underlying concepts of resonator design, material selection, and performance enhancement techniques. Here in this review paper, a comprehensive overview of various piezoelectric thin-film material properties along with different commercial microfabrication platforms with CMOS integration facility is presented. The device characteristics greatly depend on the resonator mode shape and thus suitable modes and thin-film material configurations can be chosen depending on the target frequency, application, and power budget requirements. In addition to device modeling, a synopsis of the several acoustic and material engineering approaches to enhance the figure of merit of the resonator has been presented. The future avenues of piezoelectric MEMS cover a wide spectrum of possibilities such as 5G communication, quantum processing, frequency combs, photonics integration, gesture sensors, etc.

Realizing higher operating temperatures to increase efficiency of future applications for energy conversion and storage while minimizing cost is a challenge for development of high-temperature materials. Simultaneous optimization of mechanical properties and corrosion resistance continues to be a difficult task but is essential due to the need to significantly accelerate the transition between technology readiness levels in the future. Oxidation-induced degradation will be a critical life-limiting mechanism at increased operating temperatures. Suitable high-temperature materials cannot be solely identified by time-consuming experiments and reliable computational methods incorporating the relevant physics of processes must be considered to complement the experimental efforts. In the present work, a review of the methods employed to model oxidation-induced material degradation described in literature will be discussed. Furthermore, their capability to predict lifetime and aid in material selection will be evaluated.

Phase angle is an important property of asphalt concrete (AC) mixtures that can aid in proper material selection and thereby assist in accurate design of flexible pavements. In particular, it is imperative to quantify differential phase angle behaviour for varying mixture characteristics to minimise premature failure of flexible pavements. To this end, this study aims to provide insights into the differential phase angle behaviour of wearing versus base course mixtures, field versus laboratory prepared mixtures, and for a full spectrum of binder grades. To achieve this research aim, this study employs a two-step framework. First, an artificial neural network (ANN) model is developed to predict phase angle using laboratory test data as input. Twenty-three AC mixtures consisting of different penetration grade binders, varying mix proportions, and mix types are used for phase angle testing performed at four testing temperatures (4.4, 21.1, 37.8, and 54.4 °C) and six loading frequencies (25, 10, 5, 1, 0.5, and 0.1 Hz) using the asphalt mix performance tester equipment. In the second step, a sensitivity/parametric analysis is performed for the phase angle model revealing the differences in phase angle characteristics of wearing and base course, field and laboratory mixtures as well as mixtures prepared with different binder grades. Furthermore, a comparison of the proposed ANN model with linear and non-linear regression models is performed, and the ANN model outperforms the competing models. The developed ANN model can be used as a surrogate to laboratory testing and utilised by transport departments and pavement analysts to characterise the phase angle behaviour of heterogenous AC mixtures.

Over the last decades, most automakers have started to append sustainable materials to lighten the weight in their vehicles to meet stringent, rigorous environmental regulations, which will be more economical, sustainable and improve fuel efficiency. It will also improve the relationship between power and weight of the vehicles, which will translate into greater performance from the present condition. Nowadays, Multi-criteria Decision Analysis (MCDA) is one of the fastest-growing areas of operations research. The methods of MCDA distinguish themselves in terms of procedures, theoretical assumptions, and type of decision addressed. This diversity poses challenges to the process of selecting the most suited method for a specific real-world decision problem. In this research paper, an inter-criteria co-relation model is adopted to solve a real-world discrete sustainable automotive material selection problem.

High-quality tellurium zinc cadmium (CZT) crystal materials and tellurium cadmium mercury (MCT) epitaxial materials are the key materials for the preparation of high-performance MCT-cooled detectors. Studying the relationship between material defects and device imaging is essential for improving the material quality and device performance. In this work, we summarize the defects of the CZT single crystal and the surface defects of the MCT film. Furthermore, we demonstrate the effect of CZT and MCT material defects and lattice matching on the imaging performance of the chips, and summarize the material quality improvement and the standard control methods. Through processes such as heat treatment, the size of the inclusions is controlled to be less than 20 μm and the density is less than 20 cm−2. A focal plane array (FPA) with good uniformity imaging (NETD 14.9 mK, defective pixel rate 0.03%) can be obtained by improving the material preparation level and formulating suitable material selection standards. Based on the continuous improvement of yield of FPA preparation process, MCT detectors can be fabricated in batches based on the optimized material quality.

Background This study evaluates the mechanical performance of deep margin elevation technique for carious cavities by considering the shape designs and material selections of inlay using a computational approach combined with the design of experiments method. The goal is to understand the effects of the design parameters on the deep margin elevation technique and provide design guidelines from the biomechanics perspective. Methods Seven geometric design parameters for defining an inlay’s shape of a premolar were specified, and the influence of cavity shape and material selection on the overall stress distribution was investigated via automated modelling. Material selection included composite resin, ceramic, and lithium disilicate. Finite element analysis was performed to evaluate the mechanical behavior of the tooth and inlay under a compressive load. Next, the analysis of variance was conducted to identify the parameters with a significant effect on the stress occurred in the materials. Finally, the response surface method was used to analyze the stress responses of the restored tooth with different design parameters. Results The restored tooth with a larger isthmus width demonstrated superior mechanical performance in all three types of inlay materials, while the influence of other design parameters varied with the inlay material selection. The height of the deep margin elevation layer insignificantly affected the mechanical performance of the restored tooth. Conclusions A proper geometric design of inlay enhances the mechanical performance of the restored tooth and could require less volume of the natural dentin to be excavated. Furthermore, under the loading conditions evaluated in this study, the deep margin elevation layer did not extensively affect the strength of the tooth structure.

Environmental awareness of the effects of single-use plastic packaging and the shortage of non-renewable resources have encouraged the search for alternative materials. Most of single-use plastic p...

The paper reviews the studies on sustainable electronics reported in the literature and determines opportunities through which the expansion of sustainable electronic products is possible. The sust...

This paper presents the design and analysis of the RF-MEMS Capacitive type switch. Here, we have proposed different stages of shunt switches for better performance. The objective of the proposed work is to design different beam structures and to calculate pull-in voltage with various gaps, beam thickness, and materials in FEM tool. By decreasing the pull-in voltage we have taken perforations and different meandering techniques (uniform and non-uniform). The material selection impacts the switch performance, here the dielectric material is taken as silicon nitride, the beam material is considered as gold, because of its high conducting material. The pull-in voltage of the proposed non-uniform meander type switch is 1.9 V, the RF-performance is measured in the HFSS and ADS equivalent circuit simulator tools, the return and insertion losses are obtained as −41.74 dB and -0.95 dB at 43 GHz, 40.10 GHz. The switch measured better isolation as – 36.25 dB, -20.55 dB at 20-40 GHz. The switch performance is obtained at 20-50 GHz range, therefore it can be feasible for 5G applications.

The outbreak of the Covid 19 disease has caused disaster to the people. The emergence of this disease’s outbreak encourages the importance clean lifestyle. In order not to easily contracted the Covid 19 disease, it is necessary to make automatic handwashing equipment to prevent people from having direct contact with the equipment. In this research the design and testing of an automatic handwashing equipment based on solar energy were carried out. The purpose of this research was to determine the capacity of the sun's intensity to provide electrical energy through the solar module to the battery which will be used to supply electrical energy of solar energy-based automatic handwashing equipment. The method used in this research was the Palh and Beitz method approach and the experimental method which started with the design, material selection, assembly and testing. The design produced equipment specifications for a solar module framework with a height of 100 cm, a width of 80 cm, a length of 100 cm, while for a sink frame with a height of 90 cm, a width of 45 cm, and a length of 55 cm. The test was carried out in three phases, phase one was testing the module input power. The module input power in the test produced a power of 2461 Watts with a solar radiation intensity of 3237 W / m2. The peak intensity and power of the sun was shown at 13.00 WIB. The second phase of the test was the length of time needed to charge the battery took 2.5 hours. The third phase of the test was the power needed for sensors and pumps of 358 Watts. The power requirement of 358 Watts could be supplied by a 100 Wp solar panel, since the power released from a 100 Wp solar panel is 400 Watts.

A state of the art review on Radio Frequency Micro-Electromechanical Systems (RF MEMS) capacitive switches is reported by considering two key aspects: (1) materials selection approaches for improving performance, and (2) fabrication methods used in capacitive MEMS switches. The beam and dielectric materials used in capacitive MEMS switches and the performance achieved through them are reviewed and reported by a rigorous literature survey. Further, materials selection approaches for the beam membrane and the dielectric layer are discussed using Ashby’s methodology, and other associated methods based on it, which uses material indices to evaluate the performance of a switch. Performance indicators for the beam materials selection are the pull-in voltage, RF loss, thermal residual stress, contact resistance, thermal conductivity, and maximum displacement, whereas the hold-down voltage, dielectric charging, leakage current, heat dissipation, capacitance ratio, and stability are performance indicators in dielectric materials selection. MEMS switch fabrication can be achieved through bulk micromachining processes and surface micromachining processes, but the surface micromachining process has been preferred over the last few decades. The fabricated MEMS switch components can be integrated using a monolithic complementary metal oxide semiconductor–micro-electromechanical systems (CMOS-MEMS) process for the realization of applications in sensors, resonators, amplifiers, phase shifters, and MEMS satellite vehicles for space applications. CMOS-MEMS monolithic fabrication is discussed further with the help of fabrication process involved and the process technology. The TSMC-CMOS 0.35 $$\upmu \hbox {m}$$ technology is one of the leading technologies in CMOS-MEMS fabrication and is mainly used.

In addition to vital functions, more subsidiary functions are being expected from wearable devices. The wearable technology thus far has achieved the ability to maintain homeostasis by continuously monitoring physiological signals. The quality of life improves if, through further developments of wearable devices to detect, announce, and even control unperceptive or noxious signals from the environment. Soft materials based on photonic engineering can fulfil the abovementioned functions. Due to the flexibility and zero-power operation of such materials, they can be applied to conventional wearables without affecting existing functions. The achievements to freely tailoring a broad range of electromagnetic waves have encouraged the development of wearable systems for independent recognition/manipulation of light, pollution, chemicals, viruses and heat. Herein, the role that photonic engineering on a flexible platform plays in detecting or reacting to environmental changes is reviewed in terms of material selection, structural design, and regulation mechanisms from the ultraviolet to infrared spectral regions. Moreover, issues emerging with the evolution of the wearable technology, such as Joule heating, battery durability, and user privacy, and the potential solution strategies are discussed. This article provides a systematic review of current progress in wearable devices based on photonic structures as well as an overview of possible ubiquitous advances and their applications, providing diachronic perspectives and future outlook on the rapidly growing research field of wearable technology.

Highlights An introduction to the range of 2D nanomaterials and their advantages for energy scavenging applications.A variety of methods are presented for converting solar, mechanical, thermal, and chemical energies into electrical energy.A discussion of exclusive applications that exploit 2D nanomaterials for self-powered sensor devices., The development of a nation is deeply related to its energy consumption. 2D nanomaterials have become a spotlight for energy harvesting applications from the small-scale of low-power electronics to a large-scale for industry-level applications, such as self-powered sensor devices, environmental monitoring, and large-scale power generation. Scientists from around the world are working to utilize their engrossing properties to overcome the challenges in material selection and fabrication technologies for compact energy scavenging devices to replace batteries and traditional power sources. In this review, the variety of techniques for scavenging energies from sustainable sources such as solar, air, waste heat, and surrounding mechanical forces are discussed that exploit the fascinating properties of 2D nanomaterials. In addition, practical applications of these fabricated power generating devices and their performance as an alternative to conventional power supplies are discussed with the future pertinence to solve the energy problems in various fields and applications.

The purpose of this research is to overcome the shortcomings of the current direct ventricular assist device in structure design, material selection and design a pneumatic flexible actuator that can be used to drive a fully flexible cup-shaped direct ventricular assist device according to the human heart shape. In this study, the structural parameters of the flexible actuator are initially determined based on the existing research, then the flexible actuator model is constructed with SOLIDWORKS, then the model is imported into ABAQUS for finite element simulation, lastly, the actuator structure is optimized according to the simulation results. The flexible actuator is made by molding, and its mold is made by 3D printing. Finally, the final structural plan is determined by testing the mechanical properties of the flexible actuator. The pneumatic flexible actuator designed in this research can be combined into the required direct ventricular assist device in a reasonable way, which will provide ideas for the design of a fully flexible direct ventricular assist device.

PurposeThis paper aims to provide an overview of the recent findings of the mechanical properties of parts manufactured by fused deposition modeling (FDM). FDM has become a widely used technique for the manufacturing of thermoplastic parts. The mechanical performance of these parts under service conditions is difficult to predict due to the large number of process parameters involved. The review summarizes the current knowledge about the process-property relationships for FDM-based three-dimensional printing.Design/methodology/approachThe review first discusses the effect of material selection, including pure thermoplastics and polymer-matrix composites. Second, process parameters such as nozzle temperature, raster orientation and infill ratio are discussed. Mechanisms that these parameters affect the specimen morphology are explained, and the effect of each parameter on the strength of printed parts are systematically presented.FindingsMechanical properties of FDM-produced parts strongly depend on process parameters and are usually lower than injection-molded counterparts. There is a need to understand the effect of each parameter and any synergistic effects involved better.Practical implicationsThrough the optimization of process parameters, FDM has the potential to produce parts with strength values matching those produced by conventional methods. Further work in the field will make the FDM process more suitable for the manufacturing of load-bearing components.Originality/valueThis paper presents a critical assessment of the current knowledge about the mechanical properties of FDM-produced parts and suggests future research directions.

Formwork material selection is a crucial factor for the successful completion of the project. Selection of the right formwork material is essential for faster construction and improved productivity. The study reports the factors influencing the selection of different formwork material in the construction of high rise buildings through structural questionnaire survey from the client, contractor, consultant, and interviews with expert members. Total of 40 technical factors was identified from the literature and 220 filled questionnaires were received from the respondent in the state of Tamilnadu in India. The top ten factors identified as having a significant impact on formwork material selection are the accessibility to work, quality, surface finish, storage of formwork, capital cost, safety, layout of structures, lifespan, exposure to environment and labor cost. Additionally, from factor analysis 22 factors were identified to have a correlation with one another and the remaining 18 factors excluded since they do not have a correlation with other factors. The findings provide a better understanding of the factors influencing formwork selection in the Indian context and will aid construction practitioners in making effective plans and increase the existing knowledge in relation to formwork material selection and can reduce the formwork waste.

The present work shows the design of a Pelton turbine for micro hydropower. This present work aims to design a Pelton turbine for micro hydropower that can produce a maximum power output of 32kw using water resources available in Ethiopia's rural areas with a maximum head of 15 m. This present work also includes designing each component of the Pelton turbine and selecting material for each component. In this work, design calculations and detailed drawings are also shown. The design results are tabulated based on variable head and flow rate. Material selection and the reason behind the selection are shown based on criteria predetermined. Finally, the conclusion is derived from the result analysis. If the distribution of the annual flow rate of water varies, the designed turbine will work up to a minimum flow rate of 0.15 m3/s delivering a minimum of 19.04 kW output power. This turbine will also work under the variable head of 10 m to 15 m range, delivering appropriate power. This turbine will give 31.74 kW power under a full head of 15 m and 19.04 kW power under a minimum head of 10 m. The designed turbine can be used effectively for improving power shortage around rural areas of Ethiopia. It will give 31.74 kW output power if it works under full head and flow rate. It will serve 317 households living in a rural area, assuming each household consumes 100 W.

A special type of flexure bearings are installed to support a compressor motor and a displacer within a cryocooler which is used in space applications. The fatigue life of spring is a critical factor for such applications, to ensure that the cryocooler does not fail. The flexure spring is used in the setup of an eccentric type of flexure bearing. The present study analyzes various significant parameters and properties in selecting the best suitable material to achieve finite-fatigue life. To avoid a failure of such critical component, batch testing is carried out. The three materials which are compared with respective SN-curve are a] beryllium copper, b] Stainless Steel (3 0 4) and c] Titanium. The study has been carried out to find the best suitable material for flexure bearing. Finite Element Analysis (FEA) is used to understand flexure springs stress and displacement.

Structural analysis of components is an important task in design phase which ensures the success of the design before stepping for product manufacturing. The material selected for a product to serve a particular function need validation through certain analysis for the application desired. The present work aims to conduct structural analysis of spur gear pair subjected to different torque values such as 132, 190 and 225 Nm. Structural steel, Aluminium Silicon composite, AISI 4140 alloy steel and Ti6242S are the materials considered for static structural analysis to evaluate total deformation, strain energy, equivalent von mises stress and equivalent elastic strain by varying the torque for a spur gear pair. The analysis results are further taken as input for multi criteria decision making to identify the best and worst material options through COPRAS and MOORA. The weights of the individual output responses are evaluated through CRITIC method and utilized for calculating the weighted normalized matrix. COPRAS recommend Ti6242S as the best material and Structural steel as the worst preference. The recommendations of MOORA are in confliction with COPRAS. MOORA recommends Structural steel as the best material and Ti6242S as the worst option. The results are further validated through TOPSIS and it has a good agreement with COPRAS technique than MOORA. The novelty of the present work is that the results obtained from FEA have been taken as an input for multi criteria decision making for selecting the material.

In the aircraft engine, marine engine and power generation field gas turbine has wide applications. The innovation of material for gas turbine is always required because, higher the capability of the material to withstand elevated temperature, the more will be the efficiency of the engine. In this new era of technology, demand for increasing the parameter of the industrial gas turbine is growing very fast, hence the efficiency must increase. This leads the manufacturers all over the world to develop new technology, new material, and a new method of manufacturing to increase the efficiency of the industrial gas turbine. Among these, the material plays a vital role, hence it should be as such they can withstand the extreme conditions and give maximum efficiency. It is observed that 42% of failure in the gas turbine is due to the failure of turbine blades, therefore, it is an important component to be taken care of. Turbine material selection plays a vital role. In this work, materials applicable for industrial gas turbine blades are reviewed with the focus on the material properties required and comparative analysis is done to select the suitable material. The materials are reviewed based on the methods of casting. Different Superalloys with typical compositions are analysed for tensile properties at different temperatures and their chemical composition analysis is also done. With this analysis of mechanical properties of material at different temperatures and chemical composition, it is observed that alloys like Mar M247, CM 247 LC, CMSX 2 and PWA 1484 are suitable for the gas turbine blade of future generation.

In recent years, great progress has been made in integration of optoelectronic materials and fabrication technologies to improve the performance and simplify the device architecture. For next-generation optoelectronic applications, fibers are promising candidates for constructing diverse flexible and miniature electronics/optoelectronics. Recent advances of flexible fibers in integrating the functional materials with diverse optoelectronic properties open up the potential for advanced optical probes, functional surfaces, and smart textiles. In this paper, we highlight the recent advances of optoelectronic functional fibers in material selection, especially of organic materials, fabrication approaches, as well as their applications in energy conversion, photoelectric sensing, and logical response. We conclude by pointing out the challenges and future research direction in this area.

Automotive history and corrosion on a car go hand in hand. Research in all aspects of this field including protection, prevention measures and attempts to control corrosion could not solve the problem. Eventually, all the steel parts of the car start to corrode. Corrosion may not have an immediate effect on a material, but it does affect the strength, physical appearance, and can cause operating problems. Although automakers have made great strides in protecting bodywork and paintwork from this phenomenon through surface treatment and material selection, cars remain exposed to corrosion. In order to understand the phenomenon of corrosion, it is important to identify the types of corrosion, the mechanism and the prevention methods. The objective of this study is the statistical analysis of the phenomenon of corrosion in the automotive industry in Morocco. The statistical methods used in this work for analysis are Principal Components Analysis and Variable Association Methods. The data come from a survey using a total number of 100 questionnaires, which was completed by specialists in this field (Manufacturer services, laboratories, freelancers, expert in the automotive industry experts and researchers). These same specialists belong to 52% of all 121 companies, which are affiliated to the Moroccan Association for the Industry of Automotive Construction (MAIAC). The investigation expended over a period of 6 months. Survey enabled us to identify the areas of the vehicle affected by corrosion, the most frequent types of corrosion, the causes of this phenomenon and the parameters influencing corrosion of the materials composing a vehicle.

In this globalized market where competition among industries increase day by day, companies strive to remain competitive by introducing better products which are easy to manufacture and assemble by reducing the number of parts, material selection, and less cost. DFMA, which is a proven method to help in designing the products at early stages of design for a selection of material, process and assembly methods, is widely used for new product development by designers across the globe. This paper reviews present knowledge and state of the art associated with design for manufacturing and assembly and explains in detail about the case studies carried out in different areas of new product development and other engineering applications.

Rotational Molding is defined as an emerging plastic processing technique wherein a privilege of stress free plastic products is achievable. Linear Low Density Polyethylene (LLDPE) has always been on highest priority as base resin for roto moulded product. However, LLDPE lacks in the criteria where strength is a priority in few applications. Additives can build gap to enhance the mechanical properties. A proper selection of additive to deliver an appropriate needed mechanical property in roto moulded product has always been challenging. Multi-criteria decision-making (MCDM) techniques were used to address the challenge of choosing additive with different properties from a large number of alternatives. In the present research, decision models like MOORA (ranking method based on ration analysis) and TOPSIS (a compromise ranking method) techniques were made as a source of aid to evince the fibre that can be opted in mixing with the base resin for roto moulded product. A comparative study is evaluated in this research considering these two methods with distinguished natural fibres using various attribute. It has been verified in the past that MCDM methods can be used to solve the problems of selecting material in real time. The results thus obtained are relatively satisfactory and can be used to be blended with the resin in design stage of roto moulded product. Coir in the category of natural fibres has been concluded as the material on highest ranking based on the attributes utilized in solving the techniques.

Scarcity of electricity created pressure to think on non-conventional energy sources. In this research work, a Savonius rotor Vertical wind turbine used and adapted for household and domestic electricity generation. Investigation on various materials of blades was carried out. The innovative turbine technology collects wind energy and converts it into electricity, which in turn to charge heavy duty battery. For the design & analysis PRO-E, ANSYS software was used. Structure steel is found suitable for such application.

Most of automotive and aerospace industries use journal bearing as support for rotating elements. It is because of such bearings exhibits prolonged material life and has better performance. In this research, material modeling and numerical simulation of an elliptic bore journal bearing with isotropic roughness is carried out for load carrying capacity (LCC) using finite difference method. The LCC is a governing parameter, which decides the bearing material and its implication for a particular bearing application. Load is evaluated by integrating the hydrodynamic pressure over bearing area. Subsequently, it is observed that bearing load depends on eccentricity(e), Non-circularity (G), L/D ratio (β) and roughness parameter (Y) due to which there is a complex effect of all these parameters on bearing performance and therefore on material selection. A grey based Taguchi optimization model is developed with four factors at two levels, to find the best combination of bearing parameters on the LCC. Optimized load carrying is achieved at e2-G1-β2-Y1 condition. The isothermal and the thermal non-dimensional loads are 7.0605 and 3.3 respectively in this condition.