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Engineered solutions are becoming more complex and multi‐disciplinary in nature. This evolution requires new techniques to enhance design and analysis tasks that incorporate data integration and interoperability across various engineering tool suites spanning multiple domains at different abstraction levels. Semantic web technologies (SWT) offer data integration and interoperability benefits as well as other opportunities to enhance reasoning across knowledge represented in multiple disparate models. This paper introduces the digital engineering framework for integration and interoperability (DEFII) for incorporating SWT into engineering design and analysis tasks. The framework includes three notional interfaces for interacting with ontology‐aligned data. It also introduces a novel model interface specification diagram (MISD) that provides a tool‐agnostic model representation enabled by SWT that exposes data stored for use by external users through standards‐based interfaces. Use of the framework results in a tool‐agnostic authoritative source of truth spanning the entire project, system, or mission. [ABSTRACT FROM AUTHOR]

Origami/kirigami, the ancient art of paper folding and cutting techniques, has provided considerable inspiration for structural design routes in the engineering and medical fields over the last few decades. The practicability of the methods and concepts of origami/kirigami has been demonstrated in several emerging classes of technologies, e.g., stretchable electronics, deformable devices, self‐assembly fabrication, etc. More and more related products are produced pursuing a folding form for better storage, deformation capacity, and multifunction realization. Herein, the innovative creased patterns of origami/kirigami designs are distinguished and discussed, and the four most widely used creased pattern types are introduced, which may potentially provide origami/kirigami related inspiration and additional solutions toward many research fields. [ABSTRACT FROM AUTHOR]

System design and engineering involves making decisions involving multiple stakeholders with diverse and, potentially conflicting, objectives. As more and more data become available with digital engineering, big data, and data science, trade‐off analytics will be an increasing important tool for engineers. We used a structured literature survey with Web of Science key words and bibliographic, categorical, and bibliometric analysis to answer 14 research questions. As our literature survey demonstrates, trade‐off analysis can be found in almost every engineering domain. We provide several insights from the literature survey for educators and practitioners. [ABSTRACT FROM AUTHOR]

In the past decade, flexible electronics have attracted significant research attention due to their distinct features and emerging applications in numerous fields such as, flexible displays, implantable sensors, and energy storage systems, among other applications. Due to the development of flexible electronics, this paper details the substrates employed to produce flexible electronic devices, given that substrates generally govern the overall device properties. The increase in research attention can be attributed to the use of films as flexible substrates, which enable the implementation of numerous design strategies and engineering methodologies, thus leading to extensive advances in the manufacturing quality and prospect of flexible electronics in various applications. This paper provides a comprehensive review of the significance of substrates in flexible wearable electronics over the past decade, such as, the substrate properties requirements, processing classification, important flexible devices, and applications, including sensing, energy storage, and other electronic devices. [ABSTRACT FROM AUTHOR]

This paper investigates the strengthening of non‐ductile reinforced concrete (RC) columns using partial steel‐plate jacketing to enhance ductile capacity. Quasi‐static cyclic loading tests were conducted on three rectangular RC columns with varying shear‐span‐to‐depth ratios, evaluating the effectiveness of steel‐plate jacketing. Results show improved ductile flexural response, high drift capacity, and maintained gravity‐loading capacity under high lateral displacements. A numerical investigation, adopting a multi‐spring fiber section model, predicted cyclic lateral strength, drift ratio, and failure mode, accurately simulating reinforcement behavior and capturing the shear‐strength enhancement due to steel‐plate jacketing. Numerical results demonstrated good agreement with experimental findings. Based on these outcomes, a simple design procedure for retrofitted concrete columns, applicable to design engineers, has been developed and reported in this paper. This study contributes valuable insights into the practical applications of steel‐plate jacketing for non‐ductile RC column retrofitting, offering a comprehensive approach to predicting their seismic performance. [ABSTRACT FROM AUTHOR]

In the humanoid robots, waist mechanism is an important structure to realize the whole body coordinated movement. This paper proposes a series–parallel mechanism of waist structure, and its kinematics and dynamics characteristics are studied. Based on the dynamic model, a backstepping sliding mode controller is designed to simulate control performance. Under the continuous disturbance force, the stability and accuracy of the mechanism are verified. Compared with the experiment, the results prove that the waist mechanism has the biomimetic spine movements and desired control performance, which can be applied to life support robots in the future. [ABSTRACT FROM AUTHOR]

Summary: The increasing expectation of structures capable of fulfilling the requirements of minimizing post‐earthquake repair or re‐occupancy has led to the emergence of damage‐control technologies. In recent years, self‐centering precast concrete wall systems that are characterized by low damage as well as full prefabrication have become a popular topic. Previous research has shown that the system is not only capable to reduce the construction time but also has the characteristics of small residual displacement and quick restoration of normal service function after a major earthquake event. Nevertheless, there is still much to be studied for high‐rise buildings and practical engineering applications. This paper introduces the process of self‐centering precast concrete wall systems from conceptual design to detailing and construction aspects of a 10‐story case study building. Specifically, the hybrid type of unbonded post‐tensioned wall is adopted with mild steel functioning as the energy‐dissipating component. The design and construction of mild steel take into account the requirements of both building function and replaceability. In addition, the lateral resisting system is decoupled from the gravity system using isolated joints for wall‐to‐floor connection. Various factors such as higher mode effects, torsional effects, and wind loads are considered in the design process in order to achieve the overall high performance of the structure. Finally, the numerical model of the designed structure is established and analyzed under both static and dynamic loading. Results show that the self‐centering wall structure studied in this paper has satisfactory seismic performance, i.e., each component and joint can work to achieve the function as expected, and has broad engineering application prospects in the future. [ABSTRACT FROM AUTHOR]

During the aircraft conceptual design phase, many different design options need to be explored and compared in a short time frame. To speed up this process, efforts have been made in the past decades to digitalize parts of the design process, with a focus on the automation of the repetitive and non‐creative tasks inherent to the iterative design process. Whilst many of the newly developed methodologies focus on specific parts of the design process, a holistic model‐based design framework, incorporating the latest design technology developments, is lacking. To fill this gap, this paper presents the latest version of the Design and Engineering Engine (DEE) framework, originally proposed in the early 2000s and progressively matured through the experience of several international research collaborations. The DEE enables the setup and execution of Multidisciplinary Design Analysis and Optimization (MDAO) problems for aircraft (sub)systems, leveraging the automated, rule‐based modeling capabilities offered by Knowledge‐Based Engineering (KBE) and recent developments in the automatic formulation and integration of MDAO workflows. While the traditional MDAO process focuses on a given product architecture, the DEE allows also architectural design studies and makes use of Model‐Based Systems Engineering (MBSE) principles to address the whole design process, from requirements modeling up to the automatic verification of the requirements. In practice, the DEE provides a single conceptual framework or template from which specific design framework instances can be formulated and executed, according to the user's needs. This paper describes the DEE architecture and its implementation concepts. Furthermore, it demonstrates the application of the DEE template to four different scenarios, ranging from a simple requirement verification study, up to the simultaneous synthesis and optimization of an aircraft system and its production process, including multiple system architecture options. [ABSTRACT FROM AUTHOR]

Although the application of model‐based systems engineering (MBSE) is an alternative for designing digital twins (DTs), MBSE possesses a steep learning curve, and quite often companies struggle to translate its theoretical benefits into their reality. Furthermore, the challenge of determining the DT model's fidelity, which brings balance between simulation accuracy and development costs, increases the modelling task difficulty. This paper presents the initial results from the research into facilitating the design of a system‐based DT, where various models are combined to obtain the desired representation of reality. The main contribution of this paper is towards MBSE practice, where a simplified eight‐step MBSE modelling approach for system‐based DTs is proposed. The modelling approach begins with the existing physical product and the need for a DT and results in a simulation model that constitutes the core of an actionable virtual twin. To shorten the MBSE learning curve, a set of guidelines is proposed to delimitate the Systems Modelling Language (SysML) use in Eclipse Papyrus, and a Python parser was built to convert the SysML models' information into the simulation model. The approach, guidelines and parser are analysed via an application example. In this example, the model's creation, validation and use are illustrated. The initial results indicate that the approach and modelling guidelines provide the necessary scaffolding for simplifying and facilitating MBSE application and SysML use in the design of system‐based DTs. [ABSTRACT FROM AUTHOR]

An observed increase in systems scale and complexity has led to a significant momentum in exploring, identifying, and adopting model based systems engineering (MBSE) tools and techniques amongst research communities and industry practitioners. Several attempts to transform systems design and engineering practices through the use of MBSE in academia and industry has led to a considerable increase in the number of articles published containing the keyword "MBSE." This growth serves as the motivation in this paper to explore the MBSE landscape with the help of text mining techniques to identify the most often used key terms, tools, and languages, in the context of research in MBSE and the thematic aspects defining the use of MBSE by researchers and practitioners. The objective of this paper is to provide a structured comprehensive overview of research contributions across the MBSE landscape by employing text mining techniques for: (a) identifying the concepts and methodologies inferred upon in relation to MBSE, and (b) classifying the literature published to identify commonalities across academic researchers and practitioners using MBSE tools and methods. For this purpose, the abstracts of 2380 relevant articles published in the period of the last two decades from five different databases are mined. It is found that the terms "SysML," "Cyber Physical Systems," and "Production" are the most used terms among researchers across the MBSE landscape with SysML being the most widely used modeling language. Further, six major thematic topics are identified that classify articles from over the last two decades with an increasing interest observed in the use of MBSE to support manufacturing and production engineering activities, especially in the cyber physical systems domain. The contributions of this paper provide a leeway on using text mining techniques to understand the research directions that are currently of interest in the field of MBSE and thereby identify potential future research directions. [ABSTRACT FROM AUTHOR]

The current first generation of Eurocodes is a suite of ten European standards for the design of buildings and civil engineering works, whose implementation started in 2010. EN 1990 sets the basis of structural design, with the other Eurocodes dealing with different materials and specific aspects of design. Geotechnical aspects of design are covered by EN 1997 "Geotechnical design", usually called Eurocode 7. The evolution of the Eurocodes started in 2012 and the main objectives of their revision were to incorporate improvements that reflect the state‐of‐the‐art in engineering design and the needs of the civil engineering market, to improve the ease‐of‐use and to harmonize practice between countries. While the original version was developed largely based on soil mechanics, the aim was that the revised version treats soil and rock on an equal basis. The second generation of the Eurocodes is now nearly finished, and the revised EN 1997 is expected to be formally approved in 2024. This paper is the first of a set of six informative papers on the revised Eurocodes and rock engineering, prepared by members of the Rock Engineering Platform of CEN/TC250/SC7, a group of rock engineering experts that has been assisting in drafting EN 1997 from a rock‐engineering perspective. The paper presents the main changes to EN 1990 and EN 1997 as far as they affect geotechnical and rock engineering design. [ABSTRACT FROM AUTHOR]

This paper presents an overview of the contents of 2nd Generation Eurocode 7 Part 2, highlighting two of the major changes introduced, being the Ground Model and the Rock Engineering implementation. The document is organized from a ground property perspective so that the role of Part 2 and the links with the geotechnical design are much clearer than in the previous edition. Its new title is a clear indication of this idea: "Ground properties" including both soil and rock properties. The need to have representative values for the ground properties is the objective of this new Part 2, which is intended to guide designers on the path to obtain those values by means of the Desk Study, Site Inspection, Field Investigation and Laboratory Testing. Given this framework, the paper explains the concepts behind the Ground Model, the main output of the Ground Investigation, which includes the ground profile, the geometric properties of the ground and its layers, groundwater, and the derived values of the ground properties, paying attention of the role of discontinuities in such ground profile. The tasks that form the Ground Investigation and the minimum number of activities to be performed are described. This new version of EN 1997 will include a Rock Engineering perspective for all above items. And finally, the ground properties of the rock material and the rock mass are listed and discussed. [ABSTRACT FROM AUTHOR]

In recent years, design thinking (DT) has become a pervasive innovation approach in the managerial community as a structured way of solving challenging problems through a human‐centered perspective. The approach fosters lateral thinking and has a huge impact on the organizational culture and the core elements of the innovation process. At the same time, the number of organizations trying to solve problems through the application of artificial intelligence (AI) is constantly growing, although more than 80% of AI projects never reach deployment due to the wrong strategic approach, poor data quality, or a lack of AI awareness among employees—and those that do remain below profitability expectations. The aim of this paper is therefore to connect the AI and DT communities by proposing a first framework supporting the development of AI solutions in a human‐centered way. The contribution of this paper is thus twofold: First, we investigate ways in which design thinking adds real value along the design process of intelligent solutions, thereby enriching the present body of design management literature. Second, we propose a first framework by linking core elements of both worlds to support strategic designers and data engineers in designing such applications. Finally, we propose a research agenda that can serve as a basis for future research directions in order to advance contributions at the intersection of the two fields. [ABSTRACT FROM AUTHOR]

The purpose of this paper is to broaden the practical notion of Taguchi's Quality Loss Function (QLF) from a static, one‐stage concept into a dynamic time‐varying tool. Taguchi challenged the old‐age notion of engineering tolerance and proposed a quadratic QLF that quantifies loss to society, caused by deviation of products and systems from their target values. Accordingly, design engineers attempt to set each technical parameter to minimize such systems' losses. Traditionally, failure mechanisms are assumed to affect systems' performance stochastically under a steady state. So often, technical parameters are set at the mid‐point between the lower and upper specification limits where they are least likely to cause a system failure. However, in reality, many failure mechanisms affect systems over time in a predictable and directional manner rather than stochastically. Such mechanisms are designated as "Directional Degrading Failure Mechanisms". The paper describes an optimized robust design method based on setting the operating points of technical parameters to explicitly counteract the effects of such failure mechanisms. Then, the paper describes how to minimize the lifetime societal loss of a given system utilizing a cardiac pacemaker system. The consequence of this approach suggests an extension to the Taguchi's QLF from its current static confines to a dynamic, time‐varying concept achieving, in our example, ≈65% reduction in lifetime societal losses. [ABSTRACT FROM AUTHOR]

An understanding of how sensemaking unfolds when elementary students engage in engineering design tasks is crucial to advancing engineering teaching and learning at K‐12 levels. Sensemaking has been widely studied in the context of science as a discipline. In this paper, we seek to contribute to the more nascent efforts to build theory about the characteristics of sensemaking in elementary school engineering. We report on an interpretive case study of a 3rd grade student team who worked with minimal adult intervention to design a solution to an engineering challenge. Considering the entire trajectory of their design process, from the given problem to the solution, we observed that they navigated through multiple epistemic conflicts while making decisions that informed their final solution. We found that these conflicts served as opportunities for sensemaking and that exploring how the students resolved conflicts shed light on their sensemaking processes. Analysis of the team's navigation through epistemic conflicts to come to a design decision helped identify two distinct kinds of engineering sensemaking: student engagement in functional reasoning as they suggested design ideas, and student engagement in mechanistic reasoning as they interpreted test results. Both processes facilitated knowledge building, which in turn supported students' engineering design decisions. [ABSTRACT FROM AUTHOR]

Technology roadmapping is an important yet challenging strategic process involving inter‐disciplinary knowledge and requiring key decision‐makers participation. To improve and facilitate this activity, a concept of model‐based technology roadmapping has been proposed in the literature as an application of model‐based systems engineering practices to the strategic planning domain. At the same time, many modern complex technical systems are required to be not only functional, efficient, and reliable, but also useful, usable, and desirable, which shifts the focus of planning to the user experience (UX). In this paper, we developed a Domain‐specific language that uniformly represents key concepts related to the four levels essential for strategic planning in the user‐oriented business context: market, UX design, engineering design, and technology. A collaborative interactive software was developed to support the proposed methodology. As a case study, a sustainable transformation of the automotive sector was tested and implemented in the software. [ABSTRACT FROM AUTHOR]

We present seismic zoning maps of the National Capital Region (NCR) of India in terms of uniform hazard spectrum (UHS) amplitudes using three different attenuation equations to model the contributions of local earthquakes around the region and distant earthquakes in northwestern Himalaya (NWH) and Hindu Kush Subduction (HKS) sources. Our results show that the shape of design spectra must depend on the nature of contributing earthquake sources, their relative activity, the potential to create large magnitudes, and their geographical placement relative to the site selected for hazard computation. Our results also show that specifying strong motion amplitudes for use in engineering design by means of peak ground acceleration and a standard spectral shape may result in significant underestimation of intermediate and long‐period ground motions critical for buildings higher than four to five stories and hence should not be used. We present zoning maps for nine possible combinations of three different local geological site conditions (sediments, intermediate sites, and basement rock sites) and three different soil site conditions ("rock," stiff soil sites, and deep soil sites). One of these maps can be readily used to extract the UHS amplitudes of the pseudo relative velocity spectrum (PSV) at any site in the NCR by specifying the local geological site‐condition parameters from a high‐resolution surface geological map of the region and determining the local soil site conditions by experiments limited to the site alone. The paper also provides a geological map of NCR on a scale of 1:1 million for a rough idea of the local geological parameters for a site of interest. [ABSTRACT FROM AUTHOR]

Digital engineering can fundamentally change the construction and operation of complex projects. Traditional engineering teams operate in siloed tools and disparate teams. Throughout a project lifecycle, data is translated manually or over brittle point‐to‐point connections, which increases the risk of silent errors. These potential errors can cascade across the effort, resulting in significant project delays and cost overruns. Furthermore, traditional engineering projects are not designed for the rapid digitization that allows for advanced analytic tools. Digital engineering can create a cohesive data "source of truth" to ensure a project is designed for the digital future. There is a need for a standard toolset to normalize and integrate project datasets. Idaho National Laboratory (INL) has developed DeepLynx, a crucial tool to mitigate this data management problem. This paper introduces INL's digital engineering approach and provides a concrete example of a digital engineering design effort currently taking place with Beartooth, a new nuclear material processing testbed project. This paper will provide the benefits, challenges, and lessons learned in using digital engineering on this complex system. The digital engineering approach is utilizing model‐based systems engineering, extended reality, and a digital twin. Finally, this paper will discuss the new possibilities provided by using a digital thread and twin during future operation of a nuclear fuel cycle testbed. [ABSTRACT FROM AUTHOR]

One of the regular activities performed by engineers during the design and development of the technical systems is to determine which sentences in a PDF specification document represent a requirement, functional architecture, design solution, variability, or other types of systems engineering (SE) data. Extracting such data from these PDF documents and transferring it into system model elements is still performed manually, requires high effort, and is error prone. Hereby, automatic extraction and classification of such SE data has a great potential, but it is still relatively scarce and a challenging task for engineers working with large PDF specification documents. One solution is to follow a suitable writing formulation which provide an immediate and easy way to classify and analyze the PDF documents. However, such formulations are not always followed strictly. As part of our work towards adopting Artificial Intelligence (AI) for Model‐Based Systems Engineering (MBSE), we have been researching the data extraction and data classification topics from PDF files in order to transfer it to system models elements. In this paper, we present the early status of a solution based on AI that uses Natural Language Processing (NLP) techniques to label the SE data existing in PDF files, extract them, and classify them into predefined classes. [ABSTRACT FROM AUTHOR]

Bridge collapses are catastrophic events with countless consequences. However, bridge engineering has progressed thanks to the knowledge acquired analyzing collapsed structures. In this direction, modern forensic techniques allow detecting weaknesses and vulnerable zones in the structural systems. It has been demonstrated that the data related to bridge failures has been fundamental for engineers to propose and update theories, concepts, and designs in bridge engineering. This paper presents a methodology to analyze the initial damage and its propagation on steel truss bridges. The first part of the paper presents a comprehensive review of state‐of‐the‐art and scientific challenges. The methodology is described in detail in the second part of the paper; it comprises two main tasks that are further divided into several activities. This methodology was developed as part of the "Pont3" project and has proven to be of great value in gaining a better understanding of how progressive collapse occurs in steel truss bridges. By using this methodology, it is possible to detect initial damage and evaluate the structural behavior of steel truss bridges, which will ultimately lead to safer and more reliable structures. [ABSTRACT FROM AUTHOR]

The purpose of this paper is to develop a global approach to predict the reliability of the high‐cycle fatigue behavior of mechanical components treated by laser shock peening (LSP). Most works that exist in the literature have introduced experimental and numerical studies. The originality of our investigation is to predict and validate the reliability of high‐cycle fatigue of the workpieces treated by LSP treatment by using the modified Crossland criterion. Based on previous works made by our team that shows the finite element simulation of the LSP process, this approach will be based on the integration of probabilistic fatigue criteria adapted to the superficially treated parts using ABAQUS software. After the validation of this approach, it will allow design engineers to optimize the operating conditions of the LSP process. Highlights: The studied specimens are treated by LSP process.The reliability of fatigue behavior based on the Crossland diagram is predicted.The reliability is determined by the "Constraint‐Resistance" approach using Monte Carlo.The iso‐probabilistic curves of fatigue reliability for various conditions are showed. [ABSTRACT FROM AUTHOR]

The Enhanced Model Reference Adaptive Control (EMRAC) algorithm, augmenting the MRAC strategy with adaptive integral and adaptive switching control actions, is an effective solution to impose reference dynamics to plants affected by parameter uncertainties, unmodeled dynamics and disturbances. However, the design of the EMRAC solutions has so far been limited to single‐input systems. To cover the gap, this paper presents two extensions of EMRAC to multi‐input systems. The adaptive mechanism of both solutions includes the σ$$ \sigma $$‐modification strategy to assure the boundedness of the adaptive gains also in presence of persistent disturbances. The closed‐loop system is analytically studied, and conditions for the asymptotic convergence of the tracking error are presented. Furthermore, when the plant is subjected to unmatched disturbances, the ultimate boundedness of the closed‐loop dynamics, which are made discontinuous by the adaptive switching control actions, is systematically proven by using Lyapunov theory for Filippov systems. The problem of trajectory tracking for space robotic arms in presence of unknown and noncooperative targets is used to test the effectiveness of the novel multi‐input EMRAC algorithms for taming uncertain systems. Four EMRAC solutions are designed for this engineering application, and tested within a high fidelity simulation framework based on the Robot Operating System. Finally, the tracking performance of the EMRAC implementations is quantitatively evaluated via a set of key performance indicators in the joint space and operational space, and compared with that of four benchmarking controllers. [ABSTRACT FROM AUTHOR]

A significant portion of Systems Engineering research deals with building methodologies, methods, frameworks, techniques, and tools for performing various systems engineering activities, which are arguably better than legacy ones. However, there is no clear guidance for systems engineering methodology building. In fact, there is barely any guidance about how to build methodology for anything. Systems researchers must practice what they preach – a systems approach – even in the very process of designing systems engineering systems and methods. This paper is a step toward forming a consolidated body of knowledge on systems methodology building – conception, design, construction, evaluation, and deployment – indeed much like the way we build systems. While some aspects of this methodology may seem intuitive, we introduce several insights that may be useful for informing researchers about the fundamentals of methodological research, as well as about the appropriate justification of such research. [ABSTRACT FROM AUTHOR]

The functional decomposition methodology forms the basis for how to design system behavior in the systems engineering literature. Unfortunately, this design approach has inherent weaknesses that do not allow for requirement sets to be both complete and design agnostic, both of which are considered necessary characteristics for good requirement sets. In practice, it is also difficult to design the behavior of complicated systems using functional decomposition since a large portion of the design challenge must be handled up‐front. This paper introduces a top‐down functional composition methodology approach to behavioral design. The paper argues that the presented methodology does not have the shortcomings associated with functional decomposition and that it also enables early and continuous‐, integration of design, test of design and validation of design. Therefore, this approach is more beneficial for engineering design of complicated systems, especially when model based systems engineering (MBSE) is applied. [ABSTRACT FROM AUTHOR]

The development of OLED displays is a non‐ergodic process in which there is continuous novel change; and comprehending emitters that are evolving requires new theory, or at least modification of that which is already possessed. For the first time, a new data‐validated closed‐form physics‐based expression is derived for the I‐V characteristics of OLEDs in this paper. Two parameters emerge from the new model: liminal current and liminal voltage. Both parameters are expressed in terms of device and material parameters, allowing a device engineer to intuitively design experiments to target low voltage operation OLEDs. Robust parameter extraction methods are proposed and validated with experimental data. [ABSTRACT FROM AUTHOR]

A new type of UHPC‐NC (normal concrete) structure in the negative moment zone was proposed to improve the bearing capacity of the connection structure in the negative moment zone of prefabricated prestressed concrete (PC) beam bridges. First, the distribution characteristics of the crack, cracking load, ultimate moment, and ductility coefficient of the new structure were obtained by the 1:4 scale model tests. The feasibility of the connection structure is verified. Then, the value ranges of critical structural parameters affecting the bearing capacity of the connection structure based on the plane section assumption analysis, including the reasonable thickness of the UHPC layer, the reinforcement ratio of the longitudinal tensile reinforcement, and the diameter of the reinforcement, are obtained. At the same time, based on the verification of the finite element model, the influence of crucial research parameters on the bending capacity of the connection structure is obtained by using the finite element method. Finally, a theoretical method for the bending moment capacity of the connection structure of the UHPC‐NC structure is proposed, considering the high ductility characteristics of UHPC materials. The average relative error between the calculation results and the finite element method is within 7.2%, which verifies the reliability of the calculation method in this paper and provides a reference for its design and engineering application. [ABSTRACT FROM AUTHOR]

Summary: Structures with replaceable energy‐dissipating elements are attractive systems for improving building resilience. Damage in these structures is mainly limited to dissipating elements, which can be replaced after earthquakes. Among the energy‐dissipating elements, viscoelastic dampers (VEDs) can dissipate energy even under small deformations while providing stable fatigue performances, which benefits high‐rise buildings in resisting both wind and earthquake loadings. This paper presents the seismic design of an engineering practice of a 10‐story shear wall building with replaceable viscoelastic coupling beams. A new type of viscoelastic material that has negligible frequency dependency is adopted to provide stable constraint for the wall piers. The design details, including VEDs, nonreplaceable segment, and the detachable connection, are exemplified. The numerical model of the replaceable structure is established and analyzed under dynamic loadings. Results confirm that the implementation of replaceable viscoelastic coupling beams improves structural seismic performance. The plastic rotation at the end of the coupling beam is significantly reduced up to 41.4% compared with the traditional coupled shear wall structure. [ABSTRACT FROM AUTHOR]

Reliability analysis of bridges is essential for the design of civil engineering structures. The classical methods, such as Monte Carlo Simulation (MCS) and subset simulation techniques, may provide accurate results. However, since the finite element model of the large‐scale civil engineering structures usually consists of a large number of degrees of freedom, structural reliability analysis of such structures is time‐consuming and computational intensive, which may restrict the use of these methods. This paper proposes a novel method for the reliability analysis of bridge under different types of loads by combining Polynomial Chaos (PC) and subset simulation techniques. The surrogate model of the limit state function is approximated by using the PC expansion, in which the PC coefficients are obtained from the least‐squares method. The subset simulation with a PC‐based surrogate model is then used to estimate the rare failure probability. Reliability analyses of bridge structures under different loading types, that is, static load, dynamic moving load, and seismic load are performed. Studies by using the MCS method and the classical subset simulation are also conducted, and the results from the proposed approach are compared with those from MCS and subset simulation to demonstrate the accuracy and efficiency of the proposed method. [ABSTRACT FROM AUTHOR]

Load‐bearing biological staggered composites, like nacre, teeth, and bone, possess an exceptional combination of material properties like high stiffness and high toughness. To date, most of the analytical research are for nacre‐like bio‐inspired staggered composites, with highly overlapped platelets. But the collagen fibril‐like staggered composites, with slender or barely overlapped platelets, are out of their scope. This motivates this work. In this paper, based on the previous research, according to the elastic‐viscoelastic corresponding principle, an analytical model for dynamic properties of general bio‐inspired staggered composites is presented. Moreover, the effect of loading frequency in a wide range is studied. The accuracy of the model is verified by comparison with existing models and finite element simulations. Besides, parametric analyses and sensitivity analysis are conducted thoroughly. The results reveal that besides the platelet concentration and the platelet aspect ratio, the platelet overlap ratio also influences the damping behavior of bio‐inspired staggered composites to a certain extent; for biological/biomimetic composites with a larger overlap ratio, higher loss modulus is possible to be achieved, and the optimal aspect ratio is mostly within [5, 30]. These findings are of great significance to the optimal design of bio‐inspired engineering materials in the future. [ABSTRACT FROM AUTHOR]

The strength of filled bolt holes of composites is an important parameter in developing the bearing bypass envelope curves for bolted joint structures in engineering design. This paper presents the procedures of tensile failure strengths and damage for a laminate with a filled bolt hole. Tests of two different cases, open‐hole tension (OHT) and filled‐hole tension (FHT), were performed and repeated seven times, respectively. A new type of virtual testing based on the LaRC05 criteria coupling with XFEM crack technique was developed to predict and analyze the crack initiation and early propagation around the bolt hole in the laminates. Two analytical methods were also adopted to predict the residual strength for a laminate after drilling. The results show that the thinner sample would present a higher strength with the same material system. It is also shown that the virtual test can well capture the failure modes, revealing that the 0° fiber has a natural function of crack arrest, the 90° layers that are the fracture pioneers with matrix tensile failure trigger the fiber breakage of 0° layers, and the failure of 45° layers occurs at the last. Additionally, an interesting phenomenon is observed that the initial failure around the filled hole edge does not affect the structural stiffness. Finally, a good agreement is achieved among the experimental, analytical and numerical results. It suggests that the results could provide a valuable guidance for the design of multi‐bolted joint structure. [ABSTRACT FROM AUTHOR]

In the development of complex engineering systems, many engineers from different disciplines collaborate to identify feasible designs that satisfy all system requirements. Analytical target cascading (ATC) is a method for the design optimization of hierarchical, multilevel systems and has been successfully employed in the design of complex engineering systems. In this paper, we propose a novel data‐driven set‐based ATC (SBATC) method for hierarchical design optimization problems using machine learning techniques. The proposed SBATC offers two advantages in engineering processes. First, it decomposes hierarchical design optimization problems into sets of suboptimization problems. The feasible regions of the suboptimization problems are explored and cascaded to lower‐level optimization problems. Using the set‐based approach, couplings between two adjacent levels in the optimization process are not required. Second, an efficient strategy is employed to determine feasible regions based on Bayesian active learning (BAL). In BAL, the Gaussian process (GP) of all cost functions is trained. An acquisition function that combines the probability of feasibility and entropy search is evaluated using posterior distributions of the trained GP. The acquisition function is maximized to generate new sampling points around the feasible regions by balancing the exploitation and exploration of the design space. To verify the effectiveness of the proposed method, numerical examples of hierarchical optimization problems are evaluated. [ABSTRACT FROM AUTHOR]

Buildings near direct current transmission lines are sensitive to the electromagnetic environment, and the measurement of the electric field above them is important in engineering design and environmental assessment in China. The models of buildings and probes in the ion flow field were established to explore the accurate measurement method of the electric field above the building. Based on the upstream finite element method and the predictor–corrector method, the influence of whether the probe was grounded or not above the building was studied. On this basis, simulation experiments and real‐type experiments were carried out. The results show that when the electrical conductivity of the building was greater than 10−10 S/m, being grounded or not would not change the results. When the building conductivity was between 10−11 and 10−12 S/m, the electric field measurement results would be increased by 30% to 120% after grounding. In the real‐type experiments on the platform with a plywood roof, the relative error in the electric field when grounded or not was only 2.6%. This proved the reliability of the calculated results. In this paper, the measuring method of the DC space charge‐modified electric field above buildings was analyzed first, and the conclusion that ground wire can be cancelled above buildings with general materials was presented. The research results can provide a technical basis for the accurate measurement of the electric field above the buildings near DC transmission lines. [ABSTRACT FROM AUTHOR]

This paper investigates the shear performance of corroded reinforced concrete (RC) beams with different stirrup corrosion rates and strengthening interventions. In this work, eight corroded beams strengthened with various interventions, including U‐shaped stirrup, bonded steel plate, and anchored steel plate strengthening techniques, were tested under static loading. The experimental shear capacity, load–deflection response, and failure modes of the unstrengthened and strengthened specimens were carefully studied. Three shear capacity models based on GB50010‐2010, ACI 318‐08, and Eurocode 2 codes were proposed and discussed. The results showed that all specimens have the same failure mode, that is, the shear–compression failure. The shear capacities are improved by 17.36%–23.61% and 23.76%–38.46% by these interventions for the specimens with 10% and 20% stirrup corrosion rates, respectively. The anchored steel plate technique provides the maximum improvement in the shear capacity. Additionally, the increased stiffness of corroded specimens with strengthening interventions is apparent when the corrosion rate is 10% but not obvious when the corrosion rate is 20%. The models based on GB50010‐2010 and ACI 318‐08 codes were proved to have higher accuracy but may overestimate the shear capacity. In contrast, the Eurocode 2‐based model comes with relatively low prediction accuracy but conservative results, and it is recommended for engineering design. [ABSTRACT FROM AUTHOR]

In this paper, a novel architecture, Baby, for robotic babies is proposed with a systems engineering design approach. A robotic baby is an autonomous learning system with minimal structures at the beginning of its life, aiming to gradually learn languages and actions from interactions with human parents and the world. Throughout the paper, the philosophy and the reasoning behind a robotic baby with a systems engineering design approach is discussed. With the architecture, system verification and validation are conducted, which shows convincing language skills in parsing, similar to observed human cognitive behaviors. A proof of concept demonstration involving an integration with a 3D printer is also presented. With preliminary results, the roadmap for further development and the positioning of the architecture are presented. [ABSTRACT FROM AUTHOR]

The application of composite materials in bogies for high‐speed electric multiple units (EMUs) has been regarded as a technical breakthrough. The application of composite materials in rail vehicles began late in China. Currently, most composite materials are used in non‐load‐bearing components on the track, and applications in bogies, tie beams, and other load‐bearing components are not mature. In this paper, we innovatively apply a design strategy using thin‐ply on the composite bolster of a bogie for a multiple unit to optimize the static strength of the composite structure under very complex loading. We applied nine unconventional loads and 11 major operating loads in total to evaluate a potential positive influence of using thin‐ply on the static strength of the composite bolster of a bogie. The numerical results showed that for all the complex loading scenarios, the application of thin‐ply could effectively improve the static strength of the composite structure, which is more effective at the location of the bolts and holes. The research results break through the traditional design ideas of composite structures and provide an effective ply design and optimization strategy for composite structure design engineering of high‐speed EMU. [ABSTRACT FROM AUTHOR]

Seismic performance of double‐column tall pier bents has to date scarcely been investigated. The deployment of link beams between columns, including numbers and locations, is generally designed according to the experience of engineers, without any sophisticated procedure. This paper proposes a response surface‐based optimization procedure that searches for optimal configurations of link beams of double‐column tall pier bents, considering multiple performance objectives. The response surface model is well‐developed by considering training samples from uniform design methods, boundary conditions, and iteration procedures. With a typical double‐column tall pier bent in southwest China as an example, the correctness of the proposed procedure is validated by comparing seismic responses with those from conventional optimization methods. Furthermore, this response surface‐based procedure possesses a substantially higher time efficiency than is the case with conventional methods, due to less nonlinear time history analyses as required. The Pareto optimal front is employed to trade off competing objectives in this example and to provide potential optimal design options for engineers. [ABSTRACT FROM AUTHOR]

The spatial power combination based on the time reversal (TR) technique is severely affected by the time‐varying characteristics of channels. In this paper, a mathematical model of TR power combination in the slowly time‐varying atmospheric channel and the concept of channel time‐varying factor are proposed to study the feasibility of this technique for spatial power combination in incompletely reciprocal channels. Combining the theoretical analysis and Monte Carlo simulations, we analyze the relationship between the power combination efficiency and the permittivity of the time‐varying atmospheric channel, which follows a normal distribution. The results indicate that the power combination efficiency of the TR technique will be lower than that of the completely reciprocal channel if the atmospheric channel is slowly varied, and the faster the channel changes, the lower the efficiency becomes. In order to keep the power combination efficiency above 50%, the channel time‐varying factor needs to be less than about 54.3% of the signal period. And when it takes more than 90%, the signals radiated by each antenna have been completely incoherent at target point. Different from the short‐distance power combination, when the target point is far away and at a high altitude, the time‐variability of the atmosphere over such a huge area is not negligible, so the power combination efficiency will be also severely affected. The mathematical model and results of this study can provide a theoretical basis for further research of long‐distance spatial power combination based on the TR technology and error estimation in related engineering design. Key Points: The spatial power combination effect of time reversal (TR) technique is severely affected by the time‐varying characteristics of channelsA model of TR power combination in time‐varying atmospheric channel and the concept of channel time‐varying factor are proposedThe relationship between the power combination efficiency and the permittivity of time‐varying atmospheric channels is studied [ABSTRACT FROM AUTHOR]

Summary: The Aquila optimizer (AO) is an efficient method for solving global optimization problems. However, the evolution of each individual learns from experience in the same group, which can easily fall into local optima. Therefore, this paper adopts the dynamic grouping strategy (DGS) of the population and proposes an improved AO algorithm to solve the global optimization problem. Different from the original AO algorithm, the DGSAO algorithm only evolves the individuals with the worst fitness in each group each time, which increases the diversity of the population. In order to verify the effectiveness of the algorithm, we tested it on 23 benchmark functions, among which the dimensions of F1$$ {F}_1 $$ to F13$$ {F}_{13} $$ are 30, 100, and 200 dimensions. The experimental results show that the DGSAO algorithm is an effective method for solving global optimization problems. At the same time, we also conduct experiments on two engineering design problems, and the results show that the DGSAO algorithm can obtain a competitive result. [ABSTRACT FROM AUTHOR]

This paper addresses performance limitations in passive clutching inertia devices due to the absence of flywheel deceleration damping. A solution introducing viscous damping to serve as the flywheel deceleration mechanism is proposed, thus forming the "CIDS" (Clutching Inertia‐Damping System). The study establishes a multi‐body motion analysis model for the CIDS within a single‐degree‐of‐freedom structure. Simulations investigate the impact of control force model parameters on the computation. The impact of additional damping on structural dynamic responses and the system's relative motion is thoroughly elucidated and revealed through dynamic simulations and multi‐body motion decomposition. The "ELS" (Equivalent Linear System) is introduced for the simplified performance assessment of CIDS. Expressions for equivalent damping and inertance are derived based on the equivalence of vibration period and energy in sinusoidal steady‐state vibration. The feasibility and accuracy of ELS for assessing CIDS's performance are validated through response analyses under harmonic and seismic excitations. Notably, displacement indicators exhibit higher precision than acceleration. When subjected to seismic excitation, selecting a more suitable excitation frequency to determine the corresponding equivalent damping can enhance the accuracy of ELS. Considering the frequency dependence of equivalent damping, a frequency‐domain‐based random response evaluation method is proposed. The influence of additional rotational damping, flywheel inertia, and structural natural period on random response is evaluated and analyzed. In CIDS with similar rotational damping and inertia, its control effect is related to the excitation. In summary, this study offers a structured framework for comprehending and evaluating the performance of CIDS, offering valuable insights into its potential engineering design, applications, and analysis. [ABSTRACT FROM AUTHOR]

Clustering analysis of sequence data continues to address many applications in engineering design, aided with the rapid growth of machine learning in applied science. This paper presents an unsupervised machine learning algorithm to extract defining characteristics of earthquake ground‐motion spectra, also called latent features, to aid in ground‐motion selection (GMS). In this context, a latent feature is a low‐dimensional machine‐discovered spectral characteristic learned through nonlinear relationships of a neural network autoencoder. Machine discovered latent features can be combined with traditionally defined intensity measures and clustering can be performed to select a representative subgroup from a large ground‐motion suite. The objective of efficient GMS is to choose characteristic records representative of what the structure will probabilistically experience in its lifetime. Three examples are presented to validate this approach, including the use of synthetic and field recorded ground‐motion datasets. The presented deep embedding clustering of ground‐motion spectra has three main advantages: (1) defining characteristics that represent the sparse spectral content of ground motions are discovered efficiently through training of the autoencoder, (2) domain knowledge is incorporated into the machine learning framework with conditional variables in the deep embedding scheme, and (3) the method results in a ground‐motion subgroup that is more representative of the original ground‐motion suite compared to traditional GMS techniques. [ABSTRACT FROM AUTHOR]

The real‐time tracking process of dim targets in space is mainly achieved through the correlation and prediction of dots after the detection and calculation process. The on‐board calculation of the tracking needs to be completed in milliseconds, and it needs to reach the microsecond level at high frame rates. For real‐time tracking of dim targets in space, it is necessary to achieve universal tracking calculation acceleration in response to different space regions and complex backgrounds, which poses high requirements for engineering implementation architecture. This paper designs a Kalman filter calculation based on digital logic parallel acceleration architecture for real‐time solution of dim target tracking on‐board. A unified architecture of Vector Processing Element (VPE) was established for the calculation of Kalman filtering matrix, and an array computing structure based on VPE was designed to decompose the entire filtering process and form a parallel pipelined data stream. The prediction errors under different fixed point bit widths were analyzed and deduced, and the guidance methods for selecting the optimal bit width based on the statistical results were provided. The entire design was engineered based on Xilinx's XC7K325T, resulting in an energy efficiency improvement compared to previous designs. The single iteration calculation time does not exceed 0.7 microseconds, which can meet the current high frame rate target tracking requirements. The effectiveness of this design has been verified through simulation of random trajectory data, which is consistent with the theoretical calculation error. [ABSTRACT FROM AUTHOR]

An Improved binary Non‐Linear Convergent Bi‐phase Mutated Grey Wolf Optimizer (IbGWO) is proposed for solving feature selection problems with two main goals reducing irrelevant features and maximizing accuracy. We used stratified k‐fold cross‐validation that performs stratified sampling on the data to avoid overfitting problems. The fitness function used in the proposed algorithm allows choosing the solution with the minimum number of features if more than one feature has the same highest accuracy. When stratified cross‐validation is performed, the split datasets contain the same share of the feature of interest as the actual dataset. During stratified sampling, the cross‐validation result minimizes the generalization error to a considerable extent, with a smaller variance. Feature selection could be seen as an optimization problem that efficiently removes irrelevant data from high‐dimensional data to reduce computation time and improve learning accuracy. This paper proposes an improved Non‐Linear Convergent Bi‐Phase Mutated Binary Grey Wolf Optimizer (IbGWO) algorithm for feature selection. The bi‐phase mutation enhances the rate of exploitation of GWO, where the first mutation phase minimizes the number of features and the second phase adds more informative features for accurate feature selection. A non‐linear tangent trigonometric function is used for convergence to generalize better while handling heterogeneous data. To accelerate the global convergence speed, an inertia weight is added to control the position updating of the grey wolves. Feature‐weighted K‐Nearest Neighbor is used to enhance classification accuracy, where only relevant features are used for feature selection. Experimental results confirm that IbGWO outperforms other algorithms in terms of average accuracy of 0.8716, average number of chosen features of 6.13, average fitness of 0.1717, and average standard deviation of 0.0072 tested on different datasets and in terms of statistical analysis. IbGWO is also benchmarked using unimodal, multimodal, and IEEE CEC 2019 functions, where it outperforms other algorithms in most cases. Three classical engineering design problems are also solved using IbGWO, which significantly outperforms other algorithms. Moreover, the overtaking percentage of the proposed algorithm is 69.56%. [ABSTRACT FROM AUTHOR]

Prussian blue (PB) and its analogs (PBAs) are considered one of the most promising materials for sodium‐ion batteries (SIBs). The typical PB with perfect structure and highly integrated lattice has excellent structural stability, but the possible structural defects inevitably generated in the synthesis process will deteriorate its structure during cycling, resulting in rapid capacity degradation, and impede their practical application. However, not all defects are detrimental, as proper defect construction can customize the local nature of PB to achieve outstanding new functions. This paper reviews various defect engineering designs for PBAs, such as the creation/suppression of cation or anion vacancies, the introduction of cation doping, the reduction of dislocation defects, and the construction of pore‐defect engineering. As a result, the structure–activity relationship between defects and electrochemical performance of SIBs is summarized. Moreover, the existing challenges and future development prospects are discussed, and the potential application of defect engineering in PBAs for SIBs is emphasized. [ABSTRACT FROM AUTHOR]

Verification activities, such as inspection, testing, analysis, and demonstration, improve one's confidence in the system meeting the system requirements during the development process. Frequent verification is often advocated as a strategy that minimizes costs of rework over the entire design process, where frequent verification involves verifying after any change in the design. However, this strategy is yet to be validated. In this paper, we develop a belief‐based model of verification in systems design to determine the conditions under which frequent verification is an optimal strategy for a vertically integrated organization. Our model uses belief distributions to capture the organization's dynamic confidence in the system design meeting a requirement of interest during the development process. It also captures the organization's dynamic confidence in the correctness of its development activities (or design process) as a function of past verification activities and current system maturity. The analysis of our model shows that frequent verification is a cost‐minimizing strategy for any level of belief in satisfying the requirement only when the organization has high confidence in the correctness of its design activities and the expected cost to rework a faulty design is greater than the costs to set up the verification activities throughout the development process. Otherwise, strategies with infrequent verification are superior. Our work contributes to the growing body of literature on the theoretical foundations of systems engineering and engineering design and seeks to provide practitioners with a means to determine optimal verification strategies. [ABSTRACT FROM AUTHOR]

Summary: In the last decades, topology optimization has been widely investigated as a preliminary design tool to minimize the use of material in a structure. Despite this, applications to realistic three‐dimensional engineering problems are still limited. This study provides the instruments for the definition of a versatile and integrated framework in order to apply topology optimization to large‐scale 3‐D domains for the design of efficient and high‐performing structures. The paper proposes a novel topology optimization strategy to identify the optimal layout of lateral resisting systems for tall buildings through the adoption of Mindlin–Reissner shell elements for the discretization of the continuum design domain. The framework is based on the practical interoperability between MATLAB, Ansys, and computer‐aided design (CAD) environments to incorporate optimization routines in the conceptual design phase of structural systems. Finally, the paper examines a three‐dimensional tall building case study in order to demonstrate the applicability of the proposed procedure to realistic Civil Engineering design problems and its robustness in finding optimal layouts free from mesh‐dependency instabilities. [ABSTRACT FROM AUTHOR]

The study of robustness in single-stage manufacturing has been surveyed by many researchers, while modeling of robustness in multistage manufacturing using multivariate data is seldom explored. The aim of this paper is to develop a methodology to model process robustness in a multistage manufacturing system. This paper proposes a methodology to study the robustness of a multistage process that creates a component and process capability that acts as a surrogate measure of robustness. A powerful technique to facilitate the analysis of the mentioned problem, response surfaces express the behavior of responses considering the above controllable factors (quality characteristics). A common approach to estimating response surfaces using experimental data is the ordinary least squares method. Because this method is very sensitive to outliers and correlated responses, in this paper, a robust coefficient estimation method is proposed for multiresponse surfaces in multistage processes based on M-estimators. The results show that considering the proposed robustness criteria based on a multivariate process capability index, the robust multistage process would perform better than the individual stage process. This paper adds to the body of knowledge on the robustness of multistage manufacturing processes, and also the relationship between robustness and capability is to be explored as surrogate robustness indices in the multistage process. The efficiency of the proposed approach is assessed by a small simulation study besides a real manufacturing case study. Copyright © 2017 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The leakage of molten salt storage tanks in concentrating solar power plants has attracted much attention. This paper focused on seepage and migration characteristics of molten salt in the thermal‐steady foundation fillers with different configurations after leakage occurs through a self‐built experimental system modeling the actual leaking process. The results show that the thermal insulation of light expanded clay aggregate (LECA) as foundation fillers is better than that of sand and gravel. When the operating temperature is 565°C, the average temperatures of each layer of LECA, sand, and gravel are 131.73°C, 141.91°C, and 149.27°C, respectively. And the seepage depths in light expanded clay aggregate, sand, and gravel are 482 mm, 223 mm, and 270 mm, respectively. It is found that the seepage depth of molten salt distinctly increases with higher operating temperature in all kinds of fillers. Nevertheless, the seepage depth of molten salt in the multi‐layer fillers diminishes with the increase of the thickness of the sand or gravel layer. The results obtained from this research would be helpful for the engineering design of storage tank foundations and reduce economic losses and the complexity of accident handling. [ABSTRACT FROM AUTHOR]

Reliable hysteretic modeling is essential for the evaluation of existing reinforced concrete (RC) buildings. Also, tall buildings and other structures of high importance require reasonably accurate seismic nonlinear time‐domain analysis for design, which includes load–displacement behavior and hysteretic modeling. However, the hysteretic behavior of RC members is very complex and challenging to predict. Currently, the Pivot hysteresis model is used to predict the hysteretic response of members with parameters α and β representing the unloading stiffness and pinching, respectively, determined using the geometric and reinforcement details in column members. However, the hysteretic response is fairly different for flexure and shear failure modes and must be accounted for to derive accurate hysteretic predictions. In this paper, an effort has been made to improve the existing approach for columns by deriving α and β separately for flexure and shear modes of failure. The chosen variables to control α and β are axial load ratio (ALR), longitudinal and transverse reinforcement indices. Equations for α and β were calibrated through optimization of energy dissipation from 113 column specimens subjected to cyclic loading, using an advanced optimization algorithm known as Simulated Annealing. The proposed formulations can improve the accuracy of the Pivot hysteresis model for column members by capturing pinching and stiffness degradation more reasonably under different failure modes. The proposed approach can aid design engineers in performing a more reliable and accurate analysis of complex structures. [ABSTRACT FROM AUTHOR]