Alternative Design Concepts Research Articles

Harnessing Holey MXene/Graphene Oxide Heterostructure to Maximize Ion Channels in Lamellar Film for High-Performance Capacitive Deionization.

2D Ti3C2Tx MXene-based film electrodes with metallic conductivity and high pseudo-capacitance are of considerable interest in cutting-edge research of capacitive deionization (CDI). Further advancement in practical use is however impeded by their intrinsic limitations, e.g., tortuous ion diffusion pathway of layered stacking, vulnerable chemical stability, and swelling-prone nature of hydrophilic MXene nanosheet in aqueous environment. Herein, a nanoporous 2D/2D heterostructure strategy is established to leverage both merits of holey MXene (HMX) and holey graphene oxide (HGO) nanosheets, which optimize ion transport shortcuts, alleviate common restacking issues, and improve film's mechanical and chemical stability. In this design, the nanosized in-plane holes in both handpicked building blocks build up ion diffusion shortcuts in the composite laminates to accelerate the transport and storage of ions. As a direct outcome, the HMX/rHGO films exhibit remarkable desalination capacity of 57.91mg g-1 and long-term stability in 500mgL-1 NaCl solution at 1.2V. Moreover, molecular dynamics simulations and ex situ wide angle X-ray scattering jointly demonstrate that the conductive 2D/2D networks and ultra-short ion diffusion channels play critical roles in the ion intercalation/deintercalation process of HMX/rHGO films. The study paves an alternative design concept of freestanding CDI electrodes with superior ion transport efficiency.

On the Multidisciplinary Design of a Hybrid Rocket Launcher with a Composite Overwrapped Pressure Vessel

A multidisciplinary design optimisation (MDO) study of a hybrid rocket launcher is presented, with a focus on quantifying the impact of using composite overwrapped pressure vessels (COPVs) as the oxidiser tank. The rocket hybrid propulsion system (RHPS) consists of a combination of solid fuel (paraffin) and liquid oxidiser (NOx). The oxidiser is conventionally stored in metallic vessels. Alternative design concepts involving composite-based pressure vessels are explored that could lead to significant improvements in the overall performance of the rocket. This design choice may potentially affect parameters such as total weight, thrust curve, and maximum altitude achieved. With this eventual impact in mind, structural considerations such as wall thickness for the COPV are integrated into an in-house MDO framework to conceptually optimise a hybrid rocket launcher.

APPLYING DESIGN ALTERNATIVE APPROACH TO OPTIMIZE COMFORT, SAFETY, AND COST-EFFECTIVENESS IN THE REDESIGN OF ACCOMMODATION ROOMS ON THE SHIP KM TAREX 2

In late December 2021, the ship KM Tarex 2, owned by PT. Pelayaran Mandala Sejahtera Abadi, underwent its annual docking at PT. Tambangan Permai Raya. During this time, the ship was found to be in a state of disrepair, including its accommodation rooms. The ship's current condition, feedback from stakeholders, and financial considerations served as the catalyst for a comprehensive interior redesign, with a primary focus on enhancing comfort, safety, and economy. The interior redesign of the accommodation spaces on the ship KM Tarex 2 involved the exploration of two alternative design concepts. These concepts centered around the Owner's Room, Crew's Room, Messroom and Life Jacket Storage. Alternative Design 1 adopted a Contemporary Concept, while Alternative Design 2 embraced a Modern Minimalist concept. The selection process for these designs involved soliciting feedback from a panel of 18 individuals, consisting of 12 representatives from PT. Pelayaran Mandala Sejahtera Abadi, 3 individuals from PT. Tambangan Permai Raya, and 3 crew members of the ship KM Tarex 2. Ultimately, Alternative Design 1 garnered an average approval rating of 67% across all rooms, surpassing Alternative Design 2 in preference. The selected design alternatives were evaluated for compliance with regulatory standards, achieving a 100% compliance rate for each room and an average comfort rating of 40%. Additionally, the chosen materials, as determined through a Google Form questionnaire, included ALUMETAL brand ACP Materials for room lining and ceiling, along with Henan Fortovan brand LVT for ship deck covering. These materials received an average approval rating of 61%. Economically, the analysis of material costs demonstrated that the project could be undertaken without exceeding the ship's annual income, ensuring financial feasibility.

DESAIN KONSEP PURWARUPA MESIN INJECTION MOLDING TIPE VERTIKAL UNTUK DAUR ULANG LIMBAH PLASTIK SKALA RUMAH TANGGA

Plastic waste is the main cause of environmental pollution. It is necessary to research the design of the Injection Molding machine to process plastic waste. This study describes the design concept of a vertical type Injection Molding machine prototype by considering the factors to be utilized by small-scale plastic recycling businesses. The design stage starts from the identification of component requirements to the design of 3D drawings. The results of this study obtained a prototype design of a Vertical Injection Molding Machine. The embodiment of the design is not only determined directly by the design team and the manufacturing team, but is obtained from customer requests described in the technical specifications. At the concept design stage, there are 5 sub-functions and each function has 3 to 4 options. From the combination of these sub-functions and options, 3 assembly sketches were obtained so that 3 alternative design concepts were obtained. From the results of the concept assessment, design concept C was chosen from several alternative concepts.

DECISION ANALYSIS FOR OPTIMAL CONCEPTUAL DESIGN OF CONCURRENT BRAKE ACTUATOR

Enhanced capabilities and customization in designs demand a thorough conceptual design phase for products or equipment. To ensure favorable outcomes, a comprehensive analysis of multiple design concepts is vital. This paper aims to conduct a decision analysis to determine the most suitable design for a concurrent brake actuator (CBA) among a range of alternative design concepts. It presents the development of the conceptual design of the CBA mechanism, which serves as a foundational mechanism design for future CBA development. Four mechanism design concepts were generated by utilizing the expanding curvature contour design, linear contour design, tilted position linear slope, and the nonlinear radius profile of the cam roller. The assessment of potential failures in the CBA concept design was performed by employing the risk priority number (RPN) within the framework of Design Failure Mode and Effects Analysis (DFMEA). The data obtained from DFMEA was utilized to conduct thorough analyses of motion and stress performance for each conceptual design using commercial software. Subsequently, the most optimal concept design for the CBA was chosen. This decision was reached by selecting the CBA concept design that achieved the highest score during the evaluation process, which employed a weighted decision matrix. According to the findings, the optimal CBA concept design was determined to be CBA Design B with the highest total score of 102 based on an RPN score is 32 and maximum stress of 3.647 x 104 N/m2. Its expanding linear contour design effectively distributes nonlinear brake force while minimizing failure risk, forming the foundational framework for future CBA development.

Application of Segmented and Prestressed Supporting Structures in Bridge Crane Systems: Potentials and Challenges

In this paper, an alternative design approach to the construction of bridge crane systems is analyzed with respect to the potentials and challenges of use based on two possible construction methods. Compared to conventional crane bridges, which are manufactured as a single part, the innovation of the approach relates to designing the crane bridge in segments and assembling it from standardized individual components, which are small in dimension, to form a plug-in structure. These are then prestressed by means of a tensile member to establish the load-bearing capacity. The motivation of the alternative design concept arises from a challenging manufacturing and costly transportation of common crane bridges. Here, the different design approaches are first presented as to how a segmental crane bridge can be constructed and which function the involved components fulfill. In this context, the novel construction method also gives rise to new constraints that are not covered by the common design standards and are therefore discussed. The paper concludes with a comparative study to identify advantages and disadvantages of both concepts regarding defined criteria with the aim of determining design improvements and elaborates the potentials and challenges of the approach with respect to a future industrial implementation. Moreover, these findings additionally form the basis for further research work in this area.

Assessment of Reactor Physics Characteristics of Prismatic Fuel Concepts With a Hydrogen-Based Moderator for Use in a Fluoride Salt-Cooled Small Modular Reactor

Abstract Fluoride-salt-cooled high temperature reactor (FHR) effectively combines the solid fuel and moderator design of high-temperature gas-cooled reactor (HTGR) technology with the fluoride salt coolant (LiF-BeF2, FLiBe) of molten salt reactor (MSR) technology, enabling low-pressure (∼1 atm, 101.325 kPa), and high-temperature (∼700 °C) operations. The design and operational features of the FHR make it a potentially attractive option for a small modular reactor (SMR), provided that it can be modified and made physically small and operate at a low-enough power level (<350 MWth/<150 MWel). Most FHR-SMR designs use high-assay low enriched uranium (HALEU) fuel in the form of tri-structural isotropic (TRISO) fuel particles, combined with the use of a graphite moderator. However, there are alternative design concepts for an FHR-SMR that may offer superior performance characteristics, while utilizing an alternative fissile fuel supply option. In this exploratory study, lattice physics calculations were performed with Serpent to evaluate an alternative FHR-SMR prismatic fuel block design concept using coated annular fuel pellets instead of TRISO-particle fuel compacts, along with the use of hydrogen-based solid moderator rods made of 7LiH. In initial studies, it was found that fuel blocks with 120 moderator rods made of 7LiH tended to have large positive temperature reactivity coefficients (TRCs), which is undesirable for safety reasons. However, reducing the number of moderator rods to 90 or 54, while increasing the number of fuel rods and coolant holes led to low or negative temperature coefficients. For a prismatic fuel block design with 54-7LiH moderator rods, the isothermal temperature coefficient of reactivity (Isothermal TRC), with simultaneous changes in the fuel (F), graphite (G), hydrogen (H), and coolant (C) temperatures, ranges between −0.159 mk/K and −0.054 mk/K, depending on the operating temperature and fuel burnup. Such alternative FHR-SMR fuels could achieve a single-batch core life of ∼10 years with low enriched uranium (LEU) fuel, and ∼45 years with HALEU, in a 350-MWth reactor core.

Enhancement of polysiloxane/epoxy resin compatibility through an electrostatic and van der Waals potential design strategy

The unclear molecule structures-compatibility relationship obstructs the enhancement of compatibility between polysiloxane and epoxy resins. Herein, we reveal the molecule structures-compatibility relationship and propose a synergistic design strategy to improve compatibility. Taking three typical terminal molecular structures (-NH2 group, –OH group and epoxy group) as examples, it is found that the solubility parameter and binding energy parameter of polysiloxanes are dominated by van der Waals interaction, which is closely related to the number of terminal atoms. The –NH2 group is with the strongest electrostatic interaction due to the strong electrostatic potential and low steric hindrance. On this basis, silicone prepolymer is successfully synthetized to improve compatibility through synergistically enhancing the van der Waals interaction and electrostatic interaction by increasing the number of terminal atoms and introducing –NH2 group. Consequently, Si element is uniformly distributed in the epoxy resin with silicone prepolymer, which indicates highly compatible effects. The hydrophobicity of epoxy resin is also significantly improved about 19.03% by the silicone prepolymer. The established molecular structure-compatibility relationship and proposed synergistic design strategy open up an alternative design concept for compatibility improvement in multiphase organic polymers and can be applied in insulation, moisture-proof and other fields.

Analytical study on the inflated shape of a super pressure balloon covered with a diamond-shaped net

In the last two decades, extensive efforts have been made to develop a large super pressure balloon (SPB) capable of carrying heavy payloads for scientific observations of long durations. Due to recent achievements by the NASA Balloon Program Office, practical operations of large-scale lobed-pumpkin SPB will be realized in the near future. Meanwhile, the research team initiated the development of a lightweight SPB with an alternative design concept, in which the entire balloon is covered by a diamond-shaped net. In this work, the static structural response of the proposed SPB is analyzed by establishing a mathematical model to predict its inflated shape. This model is validated by comparing the generated results with those obtained from nonlinear finite element analysis. Excellent agreement between the analytical solutions and the corresponding finite element results was obtained. On the basis of the mathematical model, the inflated shape of the SPB is investigated and unique structural characteristics are deduced, i.e., the balloon inflates into a cylinder-like shape for a certain geometry of the cover net. This structural feature can be explained by considering the equilibrium of forces applied to the cover net.

Development of a planning support system to evaluate transit-oriented development masterplan concepts for optimal health outcomes

There is growing consensus that planning professionals need clearer guidance on features of the built environment that promote health benefits. Concomitantly, the smart city movement has created renewed opportunity and interest in data-driven urban modelling to support land use planning. Planning Support Systems (PSS) are spatially enabled computer-based analytical tools incorporating health-related metrics that apply empirical evidence on built environment relationships with health-related outcomes to inform real-world urban design, urban planning and transportation planning decisions. This paper presents the development of the Urban Health Check PSS to use local empirical data to explore and predict relative health impacts associated with proposed urban design planning changes from alternative new station precinct masterplan concepts. We present a case study where we compare a baseline scenario with alternative design concepts for a new train station precinct in Perth, Western Australia, that incorporated possible built environment interventions. Subsequently, we discuss potential future applications of health impact PSS for the translation and application of health evidence into practice.

Combining Macro- and Mesoscale Optimization: A Case Study of the General Electric Jet Engine Bracket

Topology optimization (TO) is a mathematical method that optimizes the material layout in a pre-defined design domain. Its theoretical background is widely known for macro-, meso-, and microscale levels of a structure. The macroscale TO is now available in the majority of commercial TO software, while only a few software packages offer a mesoscale TO with the design and optimization of lattice structures. However, they still lack a practical simultaneous macro–mesoscale TO. It is not clear to the designers how they can combine and apply TO at different levels. In this paper, a two-scale TO is conducted using the homogenization theory at both the macro- and mesoscale structural levels. In this way, the benefits of the existence and optimization of mesoscale structures were researched. For this reason, as a case study, a commercial example of the known jet engine bracket from General Electric (GE bracket) was used. Different optimization workflows were implemented in order to develop alternative design concepts of the same mass. The design concepts were compared with respect to their weight, strength, and simulation time for the given load cases. In addition, the lightest design concept among them was identified.

Review of User-Friendly Models to Improve the Urban Micro-Climate

Various micro-scale models for comparing alternative design concepts have been developed in recent decades. The objective of this study is to provide an overview of current user-friendly micro-climate models. In the results, a vast majority of models identified were excluded from the review because the models were not micro-scale, lacking a user-interface, or were not available. In total, eight models met the seven-point inclusion criteria. These models were ADMS Temperature and Humidity model, advanced SkyHelios model, ANSYS FLUENT, ENVI-met, RayMan, SOLWEIG, TownScope, and UMEP. These models differ in their complexity and their widespread use in the scientific community, ranging from very few to thousands of citations. Most of these models simulate air temperature, global radiation, and mean radiant temperature, which helps to evaluate outdoor thermal comfort in cities. All of these models offer a linkage to CAD or GIS software and user support systems at various levels, which facilitates a smooth integration to planning and design. We detected that all models have been evaluated against observations. A wider model comparison, however, has only been performed for fewer models. With this review, we aim to support the finding of a reliable tool, which is fit for the specific purpose.

Design Selection for New In-Flight Food Delivery and Waste Collection System of Commercial Passenger Transport Aircraft using TOPSIS

One of the important airline services that can influence the passengers’ loyalty is the in-flight meal service. In this study, the conceptual design process of new in-flight food delivery and waste collection system is carried out using the standard engineering design method to improve the current system. A critical step in this process is the design concept evaluation and selection where the best alternative design concept solution is chosen for further development. The Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS) method is applied to facilitate the selection process of the best design concept for the new improved in-flight food delivery and waste collection system. The design evaluation criteria for the TOPSIS assessment procedures are taken from previous work done on design requirements analysis for the new in-flight food delivery and waste collection system. Similarly, five alternative design concepts for the new system are taken from the results of the previous research work done. Furthermore, an online public survey is conducted to acquire the assessment rating of all alternative design concepts for each design evaluation criterion. The assessment rating is assigned using a simple Likert rating scale. From the resultant TOPSIS ranking, Concept 3 has emerged as the best design concept with a closeness rating of 0.9589, which is very close to 1. For future research work, this selected final design concept for the new in-flight food delivery and waste collection system will be forwarded to the next engineering design stage for further development.

Prediction of planarization property in copper film chemical mechanical polishing via response surface methodology and convolutional neural network

AbstractChemical mechanical polishing (CMP) is one of the most important and effective technologies to achieve global planarization for precision machining of the wafer surface. The planarization property of slurry is an essential index in evaluating the quality of the copper (Cu) film CMP process. Prediction of the planarization property is of vital significance for product quality control during the CMP process. Data‐driven approaches to predict results based on response surface methodology (RSM) and neural network (NN) to pursue better prediction performance were proposed in this paper. In our design, all three optimization methods (RSM, NN, RSM + NN) are proved to be accurate and reliable, which can predict the experimental results with finer grid accuracy under the condition of only 17 test data points. In particular, the prediction accuracy of RSM + NN method is higher than that of the other two methods, and the error is only 0.16 %. Notably, the results demonstrate that such less time‐consuming optimization methods can realize the acquisition of more desirable CMP process parameters and compositions of slurries, and the versatility and simplicity of our methods can also potentially provide an alternative experiment design concept for a wider range of applications.

Pengembangan Konsep Desain Citra Kawasan Eduwisata Herbal di Kota Batu

ABSTRACT
 The village community needs the development of alternative designs that are suitable for the Herbal Education area in Batu City for the progress of Indonesia. The activities' strategy is planning an alternative design concept for the Batu City Herbal Education Area. This community service has theoretical benefits that add insight and knowledge about determining educational tours' location with various approaches. In practical terms, several added values are useful for providing input to officials and policymakers for Batu City tourism development, specifically in developing tourism with the concept of education through city image theory. This activity's impact is a good effect of these activities, especially landmarks that function optimally in building the area's image for visitors/observers in the development of the herbal education area of Batu City. More than that, it can also provide an impression/experience to visitors/observers regarding the state of the Batu City herbal education area. Also, to support in comparing the herbal education area of Batu city.

Fusing Multi-Attribute Decision Models for Decision Making to Achieve Optimal Product Design

Abstract Manufacturers need to select the best design from alternative design concepts in order to meet up with the demand of customers and have a larger share of the competitive market that is flooded with multifarious designs. Evaluation of conceptual design alternatives can be modelled as a Multi-Criteria Decision Making (MCDM) process because it includes conflicting design features with different sub features. Hybridization of Multi Attribute Decision Making (MADM) models has been applied in various field of management, science and engineering in order to have a robust decision-making process but the extension of these hybridized MADM models to decision making in engineering design still requires attention. In this article, an integrated MADM model comprising of Fuzzy Analytic Hierarchy Process (FAHP), Fuzzy Pugh Matrix and Fuzzy VIKOR was developed and applied to evaluate conceptual designs of liquid spraying machine. The fuzzy AHP was used to determine weights of the design features and sub features by virtue of its fuzzified comparison matrix and synthetic extent evaluation. The fuzzy Pugh matrix provides a methodical structure for determining performance using all the design alternatives as basis and obtaining aggregates for the designs using the weights of the sub features. The fuzzy VIKOR generates the decision matrix from the aggregates of the fuzzified Pugh matrices and determine the best design concept from the defuzzified performance index. At the end, the optimal design concept is determined for the liquid spraying machine.

Design of tools to reduce the risk level of work postures at warping station

Based on the REBA analysis, there is a risky operator work postures in the warping work station at PT. Iskandar Indah Printing Textile because they do not use work tools. The assessment of the level of work posture risk by the REBA method gets the result that the highest work element with a final score of 10 is obtained by taking warp yarn at the warping station. This study aims to produce a design tool to reduce the level of work posture risk in warping work station operators. Then the design of tools was carried out by the Pahl and Beitz method to produce three alternative product design concepts. Based on the three ideas, the best plan is chosen by using an Engineering Design Selection, and the result is the second design concept. The selected design is an adjustable trolley with a vertical screw drive system that is comfortable to use and does not cause a bending position on the operator because it has a trolley plate that can be adjusted in height as needed. The use of the trolley causes a decrease in the level of work posture risk from a high-risk level to a small risk level with a final score of 10 to 3.

Decision concordance with incomplete expert rankings in manufacturing applications

The manufacturing field encompasses a number of problems in which some experts formulate their rankings of a set of objects, which should be aggregated into a collective judgment. For example, consider the aggregation of (1) the opinions of designers on alternative design concepts, (2) the opinions of reliability/safety engineers on the criticality of a set of failures, (3) the perceptions of a panel of customers on alternative aesthetic features of a product, etc. For these problems, Kendall’s concordance coefficient (W) can be used to express the degree of agreement between experts in a simple and practical way. Unfortunately, this indicator is applicable to complete rankings only, while experts often find it more practical to formulate incomplete rankings, e.g., identifying only the most/less relevant objects and/or deliberately excluding some of them, if they are not sufficiently relevant or well known. This research aims at extending the use of the traditional W to incomplete rankings, preserving its practical meaning and simplicity. In a nutshell, the proposed methodological approach associates a so-called “midrank” to all objects, even the ones that are not easily comparable with the other ones; subsequently, W can be applied to these midranks. The description is supported by several pedagogical examples.

Appropriateness of fuzzy weighted average and fuzzy TOPSIS based on left and right scores for optimal conceptual design

This paper presents a comparative analysis on the appropriateness of fuzzy weighted average (FWA) based on left and right scores, classical fuzzy TOPSIS and fuzzy TOPSIS based on left and right scores (FTOPSIS-LR) for deciding on optimal conceptual design. A set of alternative design concept of pipe bending machine were considered as case study. The three methods indicate the same design concept as the optimal design. However, results show that there are discrepancies in the final values. This discrepancy can be accrued to the fact that normalisation of weights allotted to the design features plays a significant role in obtaining a consistent variation in the final values of the design concepts. The effect of normalised weights occurred in the FWA method than the FTOPSIS-LR because there is a consistent variation in the final values using the FWA method compared to the large variation in the final values of the FTOPSIS-LR.

Hybridized fuzzy analytic hierarchy process and fuzzy weighted average for identifying optimal design concept

In this article, a novel hybridized Multi-Attribute Decision Model (MADM) is developed to identify an optimal design of a Reconfigurable Assembly Fixture (RAF) from a set of alternative design concepts. The model combines the comparative advantage of Fuzzy Analytic Hierarchy Process (FAHP) and the computational strength of the Fuzzy Weighted Average (FWA) based on left and right scores in order to obtain aggregates for the design alternatives considering the relative importance of the design criteria as needed in the optimal design. The model was applied to evaluate four design concepts of a RAF with six design features having numerous sub-features. Results obtained from the evaluation process shows that there are differences in final values of the design alternatives. However, a close variation exists between these values. These differences can be accrued to the interrelationships between the design features and sub-features obtained from the Fuzzy Synthetic Extent (FSE) of the FAHP and an unambiguity judgment of the FWA when aggregating availability of the design features and sub-features in the design alternatives.