Hasil untuk "Structural engineering (General)"

R. Sampath Kumar, H. C. Chittappa, Praveena Bindiganavile Anand et al.

The current study focuses on the influence of varying levels of boron-carbide (B4C) particles on mechanical and tribological characteristics of Al7075 hybrid composites that are strengthened by fixed percentages of graphite (Gr) and zirconia (ZrO2). Hybrid composites were made by stir casting the 2 and 4 wt.% of B4C to Al7075-Gr-ZrO2 matrix in two-steps. The reinforcements were evenly spread throughout the matrix was confirmed by analysis through electron microscopy SEM together with elemental mapping through energy dispersive spectroscopy was utilized. Microstructural properties, tensile, hardness, and wear behaviour of the resulting hybrid composites were tested. The findings suggest that the adding of 4 wt.% B4C shall improve the hardness of Al7075 hybrid reinforced composites to 87 BHN, the UTS by 37% (214 MPa to 293 MPa) and vice versa slight decrease in ductility was attributed due to the addition of B4C. The tribological study revealed that the resistance to wear increased with additions of B4C as the hard ceramic particles served as load bearing phases. These results demonstrate the importance of B4C variation in improving mechanical and tribological behaviour of Al7075-Gr-ZrO2 hybrid reinforced composites in potential structural and aerospace application.

Richard D. Charlesworth

Boundaries in Hypernetwork Theory (HT) are non-structural tags that restrict visibility without altering the underlying hypernetwork. They attach to hypersimplices as annotations and participate in no identity, typing, or alpha/beta semantics. Projection over a boundary, B(H, b) = pi_b(H), is filtering only: it selects exactly those hypersimplices carrying b and preserves all axioms of the structural kernel. The backcloth remains immutable, and no new structure is created, removed, or inferred. This paper formalises boundaries as a simple and conservative scoping mechanism. It clarifies their syntax, their interaction with projection, and their use in producing identity-preserving subsystem views that support modular modelling and overlapping perspectives. The account also makes explicit why conservative scoping matters: boundaries provide reproducible view extraction, stable subsystem isolation, and safe model exploration without altering the global structure. Scoped operator application is defined as ordinary structural-kernel composition applied to projected views, ensuring that view-level reasoning remains local and does not modify the global hypernetwork. This establishes a disciplined separation between immutable structure and scoped analysis while retaining full compatibility with the structural kernel. The paper includes a worked example demonstrating how boundaries yield coherent, identity-preserving subsystem views and how scoped reasoning supports refinement within these views. The result is a precise and minimal account of boundaries that complements - but does not extend - the structural kernel and completes the scoping mechanism required for practical multilevel modelling with HT.

Rashina Hoda

Agentic AI is poised to usher in a seismic paradigm shift in Software Engineering (SE). As technologists rush head-along to make agentic AI a reality, SE researchers are driven to establish agentic SE as a research area. While early visions of agentic SE are primarily focused on code-related activities, early empirical evidence calls for a consideration of a wider range of socio-technical activities and concerns to make it work in practice. This paper contributes to the emerging visions by: (a) recommending an expansion of its scope beyond code, toward a 'whole of process' vision, grounding it in SE foundations and evolution and emerging agentic SE frameworks, (b) proposing a preliminary set of values and principles to guide community efforts, and (c) sharing guidance on designing and using well-defined vocabulary for agentic SE. It is hoped that these ideas will encourage collaborations and steer the SE community toward laying strong foundations of agentic SE so it is not limited to enabling coding acceleration but becomes the next process-level paradigm shift.

Muhammad Tayyab Khan, Zane Yong, Lequn Chen et al.

Engineering drawings are fundamental to manufacturing communication, serving as the primary medium for conveying design intent, tolerances, and production details. However, interpreting complex multi-view drawings with dense annotations remains challenging using manual methods, generic optical character recognition (OCR) systems, or traditional deep learning approaches, due to varied layouts, orientations, and mixed symbolic-textual content. To address these challenges, this paper proposes a three-stage hybrid framework for the automated interpretation of 2D multi-view engineering drawings using modern detection and vision language models (VLMs). In the first stage, YOLOv11-det performs layout segmentation to localize key regions such as views, title blocks, and notes. The second stage uses YOLOv11-obb for orientation-aware, fine-grained detection of annotations, including measures, GD&T symbols, and surface roughness indicators. The third stage employs two Donut-based, OCR-free VLMs for semantic content parsing: the Alphabetical VLM extracts textual and categorical information from title blocks and notes, while the Numerical VLM interprets quantitative data such as measures, GD&T frames, and surface roughness. Two specialized datasets were developed to ensure robustness and generalization: 1,000 drawings for layout detection and 1,406 for annotation-level training. The Alphabetical VLM achieved an overall F1 score of 0.672, while the Numerical VLM reached 0.963, demonstrating strong performance in textual and quantitative interpretation, respectively. The unified JSON output enables seamless integration with CAD and manufacturing databases, providing a scalable solution for intelligent engineering drawing analysis.

Daniil Mikhalev, Siamak Fakhrayee Nejad, Serina Ng et al.

This technical letter gives a concise overview of the state-of-the-art in concrete pumping. It outlines the different pump systems, briefly describes the general flow behavior of concrete in pipes, and addresses the main challenges of pumping. It also elaborates upon factors influencing the pumping behavior and how to control the pumping process.

Roberto Rossi

Multimodal GPTs represent a watershed in the interplay between Software Engineering and Generative Artificial Intelligence. GPT-4 accepts image and text inputs, rather than simply natural language. We investigate relevant use cases stemming from these enhanced capabilities of GPT-4. To the best of our knowledge, no other work has investigated similar use cases involving Software Engineering tasks carried out via multimodal GPTs prompted with a mix of diagrams and natural language.

Michael B. Healy, Reza Jokar, Soolu Thomas et al.

In this work, we describe the design and architecture of the open-source Quantum Engine Compiler (qe-compiler) currently used in production for IBM Quantum systems. The qe-compiler is built using LLVM's Multi-Level Intermediate Representation (MLIR) framework and includes definitions for several dialects to represent parameterized quantum computation at multiple levels of abstraction. The compiler also provides Python bindings and a diagnostic system. An open-source LALR lexer and parser built using Bison and Flex generates an Abstract Syntax Tree that is translated to a high-level MLIR dialect. An extensible hierarchical target system for modeling the heterogeneous nature of control systems at compilation time is included. Target-based and generic compilation passes are added using a pipeline interface to translate the input down to low-level intermediate representations (including LLVM IR) and can take advantage of LLVM backends and tooling to generate machine executable binaries. The qe-compiler is built to be extensible, maintainable, performant, and scalable to support the future of quantum computing.

Yongxiang Shi, Yongxiang Shi, Marco Ballesio et al.

Introduction: Cracks are a key feature that determines the structural integrity of rocks, and their angular distribution can be used to determine the local or regional stress patterns. The temporal growth of cracks can be monitored in order to predict impending failures of materials or structures such as a weakened dam. Thus, cracks and their spatial-temporal distributions should be automatically monitored for assessing their structural integrity, the associated stress patterns and their potential for failure.Method: We show that the U-Net convolutional neural network, semantic segmentation and transfer learning can be used to accurately detect cracks in drone photos of sedimentary massifs. In this case, the crack distributions are used to assess the safest areas for tunnel excavation. Compared to the coarse performance of ridge detection, the U-Net accuracy in identifying cracks in images can be as high as 98% when evaluated against human identification, which is sufficient for assessing the general crack properties of the rock faces for the engineering project.Result: Based on approximately 100 h of manual cracks labeling in 127 drone photos and 20 h of network training, the U-Net was able to successfully detect cracks in 23,845 high-resolution photographs in less than 22 h using two Nvidia V100 GPUs. Meanwhile, the network was able to detect more than 80% of the observable cracks of a volcanic outcrop in Idaho without additional training. With a modest amount of extra labeling on photos of the volcanic outcrop and transfer training, we found that the accuracy significantly improved. The surprising outcome of this research is that the U-Net crack detector laboriously trained on photos of sedimentary rocks can also be effectively applied to photos of volcanic rock faces. This can be important for real-time assessment of geological hazards and lithology information for dam inspection and planetary exploration by autonomous vehicles. For another application, we accurately detected fractures and faults with a scale of tens of kilometers from Martian photographs.Conclusions: In summary, our methodology of using CNN with transfer training suggests that it can be used as a semi-universal detector of cracks in across a range of diverse geological settings.

Hong Fang, Junjie Liu, Ruijuan Ma et al.

Lutein is a high-value carotenoid with many human health benefits. Lycopene β- and ε-cyclases (LCYB and LCYE, respectively) catalyze the cyclization of lycopene into distinct downstream branches, one of which is the lutein biosynthesis pathway, via α-carotene. Hence, LCYB and LCYE are key enzymes in lutein biosynthesis. In this study, the coding genes of two lycopene cyclases (CsLCYB and CsLCYE) of a lutein-enriched marine green microalga, <i>Chlorella sorokiniana</i> FZU60, were isolated and identified. A sequence analysis and computational modeling of CsLCYB and CsLCYE were performed using bioinformatics to identify the key structural domains. Further, a phylogenetic analysis revealed that CsLCYB and CsLCYE were homogeneous to the proteins of other green microalgae. Subcellular localization tests in <i>Nicotiana benthamiana</i> showed that CsLCYB and CsLCYE localized in chloroplasts. A pigment complementation assay in <i>Escherichia coli</i> revealed that CsLCYB could efficiently β-cyclize both ends of lycopene to produce β-carotene. On the other hand, CsLCYE possessed a strong ε-monocyclase activity for the production of δ-carotene and a weak ε-bicyclic activity for the production of ε-carotene. In addition, CsLCYE was able to catalyze lycopene into β-monocyclic γ-carotene and ultimately produced α-carotene with a β-ring and an ε-ring via γ-carotene or δ-carotene. Moreover, the co-expression of CsLCYB and CsLCYE in <i>E. coli</i> revealed that α-carotene was a major product, which might lead to the production of a high level of lutein in <i>C. sorokiniana</i> FZU60. The findings provide a theoretical foundation for performing metabolic engineering to improve lutein biosynthesis and accumulation in <i>C. sorokiniana</i> FZU60.

Vladimir Travush, Petr Arleninov, Mikhail Desyatkin et al.

The features of the behavior of steel-plate composite walls for static loads are considered. Based on the analysis of modern technical and regulatory documentation, the rationale for the chosen research topic is given. A review of the literature is performed, and the features of development are noted. A detailed description and features of the experimental structures under study and the materials used are presented. The features of the test are considered, and the test equipment is described. Analytical and numerical calculations of structures for eccentric compression have been performed. The description of the calculation complex and the used models of materials is presented; the description of numerical models, the features of their construction and calculation are given, the results of calculations are presented – stress distributions, deformations, features of cracking. The general types of experimental eccentric compression wall models are presented, the nature of the loss of bearing capacity of experimental structures is described, and a picture of destruction is presented. The analysis of the experimental data obtained and their comparison with analytical and numerical calculations are performed.

Lu Wang, Yang Yang, Qiuzu Yang

During aircraft landing on water, the intense impact load may lead to significant local deformation of the fuselage skin. Ensuring the aircraft’s integrity and reliability is of paramount importance. This paper investigates the fuselage skin’s dynamic response during water entry. In the simulation of complex water entry problems, the smoothed particle hydrodynamics (SPH) method can fully leverage the advantages of the particle method. However, the traditional SPH method still suffers from the drawbacks of tensile instability, significantly affecting the computational accuracy. Therefore, this paper first introduces the improved SPH model addressing fluid and solid tensile instability issues. Furthermore, the Riemann-based contact algorithm at the fluid–solid interface is also demonstrated. Based on the above improved SPH model, the simulation of water entry of the elastic cylinder is performed to validate the efficacy of the improved SPH model. Then, the dynamic response characteristics of elastic fuselage skin and the skin–stringer–floor–column structure when it enters the water are analyzed, including the deformation features and slamming force. Lastly, based on the presented damage model, a study is conducted on the water entry of the metallic elastic–plastic skin–stringer–floor–column structure, analyzing the locations of failure and providing guidance for the structural safety design of engineering.

Alex Morehead, Jeffrey Ruffolo, Aadyot Bhatnagar et al.

Generative models of macromolecules carry abundant and impactful implications for industrial and biomedical efforts in protein engineering. However, existing methods are currently limited to modeling protein structures or sequences, independently or jointly, without regard to the interactions that commonly occur between proteins and other macromolecules. In this work, we introduce MMDiff, a generative model that jointly designs sequences and structures of nucleic acid and protein complexes, independently or in complex, using joint SE(3)-discrete diffusion noise. Such a model has important implications for emerging areas of macromolecular design including structure-based transcription factor design and design of noncoding RNA sequences. We demonstrate the utility of MMDiff through a rigorous new design benchmark for macromolecular complex generation that we introduce in this work. Our results demonstrate that MMDiff is able to successfully generate micro-RNA and single-stranded DNA molecules while being modestly capable of joint modeling DNA and RNA molecules in interaction with multi-chain protein complexes. Source code: https://github.com/Profluent-Internships/MMDiff.

K. Sun, K. Sun, M. Yousefi et al.

<p>An optimal estimation-based algorithm is developed to retrieve the number density of excited oxygen (O<span class="inline-formula">₂</span>) molecules that generate airglow emissions near 0.76 <span class="inline-formula">µ</span>m (<span class="inline-formula"><math xmlns="http://www.w3.org/1998/Math/MathML" id="M3" display="inline" overflow="scroll" dspmath="mathml"><mrow><msup><mi>b</mi><mn mathvariant="normal">1</mn></msup><msubsup><mi mathvariant="normal">Σ</mi><mi mathvariant="normal">g</mi><mo>+</mo></msubsup></mrow></math><span><svg:svg xmlns:svg="http://www.w3.org/2000/svg" width="26pt" height="17pt" class="svg-formula" dspmath="mathimg" md5hash="e23f4f729858696de5562ade75bd55ba"><svg:image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="amt-15-3721-2022-ie00001.svg" width="26pt" height="17pt" src="amt-15-3721-2022-ie00001.png"/></svg:svg></span></span> or <span class="inline-formula"><i>A</i></span> band) and 1.27 <span class="inline-formula">µ</span>m (<span class="inline-formula"><i>a</i>¹Δ_g</span> or <span class="inline-formula">¹Δ</span> band) in the upper atmosphere. Both oxygen bands are important for the remote sensing of greenhouse gases. The algorithm is applied to the limb spectra observed by the SCanning Imaging Absorption spectroMeter for Atmospheric CHartographY (SCIAMACHY) instrument in both the nominal (tangent heights below <span class="inline-formula">∼</span> 90 km) and mesosphere–lower thermosphere (MLT) modes (tangent heights spanning 50–150 km). The number densities of emitting O<span class="inline-formula">₂</span> in the <span class="inline-formula"><i>a</i>¹Δ_g</span> band are retrieved in an altitude range of 25–100 km near-daily in 2010, providing a climatology of O<span class="inline-formula">₂</span> <span class="inline-formula"><i>a</i>¹Δ_g</span>-band airglow emission. This climatology will help disentangle the airglow from backscattered light in nadir remote sensing of the <span class="inline-formula"><i>a</i>¹Δ_g</span> band. The global monthly distributions of the vertical column density of emitting O<span class="inline-formula">₂</span> in <span class="inline-formula"><i>a</i>¹Δ_g</span> state show mainly latitudinal dependence without other discernible geographical patterns. Temperature profiles are retrieved simultaneously from the spectral shapes of the <span class="inline-formula"><i>a</i>¹Δ_g</span>-band airglow emission in the nominal limb mode (valid altitude range of 40–100 km) and from both <span class="inline-formula"><i>a</i>¹Δ_g</span>- and <span class="inline-formula"><math xmlns="http://www.w3.org/1998/Math/MathML" id="M18" display="inline" overflow="scroll" dspmath="mathml"><mrow><msup><mi>b</mi><mn mathvariant="normal">1</mn></msup><msubsup><mi mathvariant="normal">Σ</mi><mi mathvariant="normal">g</mi><mo>+</mo></msubsup></mrow></math><span><svg:svg xmlns:svg="http://www.w3.org/2000/svg" width="26pt" height="17pt" class="svg-formula" dspmath="mathimg" md5hash="11467d6e86e83b59d143f98a0818d72e"><svg:image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="amt-15-3721-2022-ie00002.svg" width="26pt" height="17pt" src="amt-15-3721-2022-ie00002.png"/></svg:svg></span></span>-band airglow emissions in the MLT mode (valid range of 60–105 km). The temperature retrievals from both airglow bands are consistent internally and in agreement with independent observations from the Atmospheric Chemistry Experiment Fourier transform spectrometer (ACE-FTS) and the Michelson Interferometer for Passive Atmospheric Sounding (MIPAS), with the absolute mean bias near or below 5 K and root mean squared error (RMSE) near or below 10 K. The retrieved emitting O<span class="inline-formula">₂</span> number density and temperature provide a unique dataset for the remote sensing of greenhouse gases and constraining the chemical and physical processes in the upper atmosphere.</p>

Jiaxiang Yang, Hanyuan Deng, Zikai Tang et al.

The zeroth-order general Randić index $R^{0}_{a+1}$ of an $n$-vertices oriented graph $D$ is equal to the sum of $(d^{+}_{u_i})^{a}+(d^{-}_{u_j})^{a}$ over all arcs $u_iu_j$ of $D$, where we denote by $d^{+}_{u_i}$ the out-degree of the vertex $u_i$ and $d^{-}_{u_j}$ the in-degree of the vertex $u_j$, $a$ is an arbitrary real number. In the paper, we determine the orientations of cacti with the maximum value of the zeroth-order general Randić index for $a\geq 1$.

Zeinab Abou Khalil, Stefano Zacchiroli

Background: Software development results in the production of various types of artifacts: source code, version control system metadata, bug reports, mailing list conversations, test data, etc. Empirical software engineering (ESE) has thrived mining those artifacts to uncover the inner workings of software development and improve its practices. But which artifacts are studied in the field is a moving target, which we study empirically in this paper.Aims: We quantitatively characterize the most frequently mined and co-mined software artifacts in ESE research and the research purposes they support.Method: We conduct a meta-analysis of artifact mining studies published in 11 top conferences in ESE, for a total of 9621 papers. We use natural language processing (NLP) techniques to characterize the types of software artifacts that are most often mined and their evolution over a 16-year period (2004-2020). We analyze the combinations of artifact types that are most often mined together, as well as the relationship between study purposes and mined artifacts.Results: We find that: (1) mining happens in the vast majority of analyzed papers, (2) source code and test data are the most mined artifacts, (3) there is an increasing interest in mining novel artifacts, together with source code, (4) researchers are most interested in the evaluation of software systems and use all possible empirical signals to support that goal.

Rebekka Wohlrab, David Garlan

[Context and motivation:] For realistic self-adaptive systems, multiple quality attributes need to be considered and traded off against each other. These quality attributes are commonly encoded in a utility function, for instance, a weighted sum of relevant objectives. [Question/problem:] The research agenda for requirements engineering for self-adaptive systems has raised the need for decision-making techniques that consider the trade-offs and priorities of multiple objectives. Human stakeholders need to be engaged in the decision-making process so that the relative importance of each objective can be correctly elicited. [Principal ideas/results:] This research preview paper presents a method that supports multiple stakeholders in prioritizing relevant quality attributes, negotiating priorities to reach an agreement, and giving input to define utility functions for self-adaptive systems. [Contribution:] The proposed method constitutes a lightweight solution for utility function definition. It can be applied by practitioners and researchers who aim to develop self-adaptive systems that meet stakeholders' requirements. We present details of our plan to study the application of our method using a case study.

Wei Xu, Ingo Neumann

Simplified models are widely applied in finite element computations regarding mechanical and structural problems. However, the simplified model sometimes causes many deviations in the finite element analysis (FEA) of structures, especially in the non-designed structures which have undergone unknowable deformation features. Hence, a novel FEA methodology based on the parametric model by approximating three-dimensional (3D) feature data is proposed to solve this problem in the present manuscript. Many significant and effective technologies have been developed to detect 3D feature information accurately, e.g., terrestrial laser scanning (TLS), digital photogrammetry, and radar technology. In this manuscript, the parametric FEA model combines 3D point clouds from TLS and the parametric surface approximation method to generate 3D surfaces and models accurately. TLS is a popular measurement method for reliable 3D point clouds acquisition and monitoring deformations of structures with high accuracy and precision. The B-spline method is applied to approximate the measured point clouds data automatically and generate a parametric description of the structure accurately. The final target is to reduce the effects of the model description and deviations of the FEA. Both static and dynamic computations regarding a composite structure are carried out by comparing the parametric and general simplified models. The comparison of the deformation and equivalent stress of future behaviors are reflected by different models. Results indicate that the parametric model based on the TLS data is superior in the finite element computation. Therefore, it is of great significance to apply the parametric model in the FEA to compute and predict the future behavior of the structures with unknowable deformations in engineering accurately.

Veghova Ivana, Psotny Martin

Geometric nonlinear solution of a compressed plate is presented in this paper. Basic assumptions are specified and incremental conditional equations are derived from the variational principle of minimum of total potential energy. Full Newton-Raphson procedure, in which the stiffness matrix is updated at every equilibrium iteration, has been applied for solution. The importance of modifications of base functions for solving geometric nonlinear problems is analysed. The solved example is presented, the differences are compared and explained.

Bilal Raza, Stephen G. MacDonell, Tony Clear

This study presents an analysis of the most recent literature addressing global software engineering (GSE). We examine the current state of GSE research using a new Systematic Snapshot Mapping (SSM) technique. We analysed 275 papers published between January 2011 and June 2012 in peer-reviewed conferences, journals and workshops. Our results provide a coarse-grained overview of the very recent literature addressing GSE, by classifying studies into predefined categories. We also follow and extend several prior classifications to support our synthesis of the data. Our results reveal that currently GSE studies are focused on Management and Infrastructure related factors. Most of the studies are conducted at the organizational level using methods such as interviews, surveys, field studies and case studies. We use inter-country network analysis to confirm that the USA and India are major players in GSE, with USA-India collaborations being the most frequently studied, followed by USA-China. Specific groups of countries have dominated the reported GSE project locations. In contrast, regions including Central Asia, South Asia (except India), Africa and South East Asia have not been covered in these studies. While a considerable number of GSE-related studies have been published they are currently quite narrowly focused on exploratory research and explanatory theories. The critical research paradigm has been untouched, perhaps due to a lack of criteria and principles for carrying out such research in GSE. An absence of formulative research, experimentation and simulation, and a comparative focus on evaluative approaches, all suggest that existing tools, methods and approaches from related fields are being tested in the GSE context. However, these solutions may not scale to cover GSE-related issues or may overlook factors/facets specific to GSE.