General Structural Design Research Articles

A General Molecular Structural Design for Highly Efficient Photopyroptosis that can be Activated within 10 s Irradiation.

Photopyroptosis is an emerging research branch of photodynamic therapy (PDT), whereas there remains a lack of molecular structural principles to fabricate photosensitizers for triggering a highly efficient pyroptosis. Herein, a general and rational structural design principle to implement this hypothesis, is proposed. The principle relies on the clamping of cationic moieties (e.g., pyridinium, imidazolium) onto one photosensitive core to facilitate a considerable mitochondrial targeting (both of the inner and the outer membranes) of the molecules, thus maximizing the photogenerated reactive oxygen species (ROS) at the specific site to trigger the gasdermin E-mediated pyroptosis. Through this design, the pyroptotic trigger can be achieved in a minimum of 10 s of irradiation with a substantially low light dosage (0.4 Jcm⁻2), compared to relevant work reported (up to 60 Jcm⁻2). Moreover, immunotherapy with high tumor inhibition efficiency is realized by applying the synthetic molecules alone. This structural paradigm is valuable for deepening the understanding of PDT (especially the mitochondrial-targeted PDT) from the perspective of pyroptosis, toward the future development of the state-of-the-art form of PDT.

Octopus Predation-Inspired Underwater Robot Capable of Adsorption through Opening and Closing Claws

Underwater unmanned robots are an essential tool for human underwater exploration and detection and are widely employed in a variety of underwater operational settings. One of the hottest issues in this field is applying bionic notions to the creation of underwater unmanned robots by simulating fish swimming or cephalopod crawling. Using the tentacle suction cup adsorption technique during octopus’ predation as a model, underwater magnetic adsorption robots with the opening and closing claws were studied in this paper. First, the robot’s general structural design is presented. The claw mechanism is demonstrated by mimicking the octopus’s tentacle action during feeding, which primarily consists of an opening and closing claw that replicates the octopus’s tentacle and a magnetic adsorption unit that replicates the octopus’s suction cup adsorption. Then, the Kriging response surface optimization method is used to optimize the design of the claw mechanism to obtain excellent mechanical properties, and simulation software is used to verify. Finally, a robot prototype was built and its pool tests were conducted, with some experimental results presented. The experimental results show that after the robot reaches the predetermined position through pneumatic ejection and secondary propulsion launch, it can quickly open its claws within 0.11 s and apply 462.42 N adsorption force to complete the adsorption of the target.

ЭФФЕКТИВНОЕ ПРИМЕНЕНИЕ ИСКУССТВЕННОГО ИНТЕЛЛЕКТА В БИЗНЕСЕ ПО УПРАВЛЕНИЮ БАНКОВСКИМИ АКТИВАМИ

The asset management business is an advanced area of development in the banking and financial business sector. It has a relatively independent and complete asset and liability structure and business modules. Among them, business areas such as asset, liability and risk management are natural application scenarios. Artificial intelligence technology currently has some practical applications. At the same time, there are problems such as incomplete basic business data, strong organizational structure specifics and lack of technical reserves. As a result, there is currently no application of artificial intelligence technology used for general sorting and structural design of the banking asset management business. Based on this, this article examines the factors influencing the degree of application of artificial intelligence in the business of managing banking assets, and analyzes strategies for using artificial intelligence in the business of managing banking assets.

Clearance compatibility and design principle of the single-structured hybrid gas-magnetic bearing

PurposeThis paper aims to study the clearance compatibility of active magnetic bearing (AMB) and gas bearing (GB) to achieve a single-structured hybrid gas-magnetic bearing (HGMB), which uses a single bearing structure to realize both the functions of gas bearing and magnetic bearing.Design/methodology/approachBecause the radial clearance size of the AMB is typically ten times larger than that of the GB, radial clearance compatibility of GB and AMB needs to maximize the radial clearance of GB by adjusting structural parameters. Parametric analysis of structural parameters of GB is explored. Furthermore, a general structural design principle based on static analysis, rotordynamic performance and system stability is established for the single-structured HGMB.FindingsLoad capacity is vastly reduced due to the enlarged radial clearance of the GB. A minimum clearance needs to be ensured by increasing the bearing diameter or width to compensate for the reduced load capacity, yet indirectly raising the bearing load. Increased bearing load is conducive to stability, yet it raises the risk of rotor abrasion. In addition, excessively large bearing diameter leads to system instability, and inappropriate bearing width affects critical speeds. A general structural design principle is established and the designed HGMB–rotor processes optimal performances.Originality/valueA single-structured HGMB is proposed to address the urgent demand for high-speed, cryogenic turboexpanders with frequent starts/stops. This design applies a single-bearing structure to realize the characteristics of both GB and AMB, greatly simplifying the implementation, reducing air friction loss and raising critical speeds. This paper provides a fresh perspective on the development of cryogenic turboexpanders for hydrogen liquefaction. It theoretically validates the feasibility and provides a design guide for a single-structured HGMB system.

Plate structure design guideline for commercial alkaline water electrolyzers (AWEs) with improved liquid flow uniformity: Multi-scale quantitative criteria and experimental validation

Alkaline water electrolyzers (AWEs) holds great promise for large-scale green hydrogen production, but its commercialization is impeded by high electrical energy costs. Improving flow uniformity in AWEs is crucial to reduce energy consumption, necessitating optimized plate structure designs. Regrettably, the quantitative investigation of flow uniformity in electrolyzers is rare, due to the complex flow behavior. As a consequence, the existing designs primarily rely on empirical knowledge, lacking an efficient and systematic design guidance. This study establishes a general plate structure design strategy for commercial AWEs by introducing quantitative criteria for flow uniformity in multi-scale. The strategy comprises four steps: 1) single unit design to improve lateral liquid distribution, 2) evaluation of velocity magnitude discrepancy at horizontal sections, 3) flow behavior prediction by RTD analysis, and 4) validation through performance test. The strategy incorporates three quantitative parameters φ, δ, θ to evaluate the performance in three different levels. Two novel designs, namely, the rhombus and wedge electrolyzers are proposed to demonstrate the design strategy. Additionally, an in-situ electrolysis visualization/performance test platform is developed to vividly depict the gas-liquid flow during electrolysis and validate the effectiveness of our design guidelines. The proposed design guideline provides step-by-step guidance for the plate structure design of future high-performance commercial AWEs.

A general structural design method, dynamics modeling and application study for built-in sandwich annular traveling wave piezoelectric transducers

This study first summarized a piezoelectric excitation source arrangement guideline for sandwich annular traveling wave transducers, which can excite ideal traveling waves for driving while ensuring consistent circumferential stiffness of the annular transducer. Consequently, a general structural design method was proposed for annular sandwich traveling wave piezoelectric transducers operating with out-of-plane traveling waves based on the above-mentioned arrangement guideline. Moreover, to study the vibration characteristics of the designed transducer based on the proposed method, an electromechanical coupled dynamics model was developed using the dynamic substructure method combined with the Lagrange equation. This model is universal and has guiding significance for the design and optimization of the same type of annular traveling wave piezoelectric transducers. Thereafter, the feasibility of the transducer structure design method and the correctness of the developed dynamics model were verified through appropriate vibration measurement experiments on the transducer prototype. The measured ideal mode shape and regular elliptical motion verified the feasibility of the transducer design method, and the comparison between the vibration measurement and theoretical model calculation results confirmed the correctness of the developed dynamic model. Finally, an application study of the proposed built-in sandwich traveling wave transducer was conducted to investigate its driving characteristics. The proposed transducer was used to drive a rotor to build a traveling wave piezoelectric motor. In addition, output performance experiments of the motor prototype were conducted. The experimental results indicated that under the driving conditions of 300 N pre-pressure, 500 Vpp voltage, and 19 kHz exciting frequency, the no-load speed of the motor was 19.04 RPM, its stall torque was 1.2 N·m, the maximum output power of the entire machine reached 0.6453 W, and its maximum output efficiency was 15.87%. Moreover, the normal operation of the rotating motor further verified the feasibility of the transducer structure design approach and the reliability of the drive application. The structural design method and the corresponding dynamic model proposed in this study are expected to have important guiding significance for the design and optimization of sandwich-type annular traveling wave transducers. Furthermore, the application investigation in this study provides a typical example for the traveling wave transducer.

Performance comparison of five regression-based machine learning techniques for estimating load-carrying capacity of steel frame using direct analysis

The development of computer science has promoted the application of scientific and technological achievements to construction engineering in general and steel structure design in particular. Recently, the steel frame structure design has applied advanced analytical methods to take into account the inelastic behavior of the material and the geometric nonlinear properties of the structure, leading to the results obtained close to the real structure. In addition, to reduce computational time and effort, it has been applied advanced machine learning (ML) algorithms to predict behavior, helping to accelerate decision-making, improve efficiency, and reduce errors. In this paper, 5 popular machine learning algorithms are currently being conducted for the regression-based to estimate the ultimate load capacity of steel frames, including Linear Regression, Deep Learning, Support Vector Machine, Random Forest, and XGBoost. The effectiveness of applying these methods is tested through a numerical example surveying a 20-story space steel frame. The performance of ML algorithms is evaluated by comparing the mean-squared error (MSE) and computational efforts. The results show that among the 5 selected methods, the XGBoost has obvious advantages and is superior in terms of both MSE and calculation time.

Design Concepts for Solution and Solid-State Emitters - A Modern Viewpoint on Classical and Non-Classical Approaches.

For a long time, luminescence phenomena were strictly distinguished between the emission of isolated molecules in dilute solutions or close-packed structures such as in powders or aggregates. This changed with the breakthrough observation of dual-state efficient materials, which led to a rapid boost of publications examining the influence of structural features to achieve balanced emission with disregarded molecular surroundings. Some first general structural design concepts have already been proposed based on reoccurring patterns and pivotal motifs. However, we have found another way to classify these solution and solid-state emitters (SSSEs). Hence, this minireview aims to present an overview of published structural features of SSSEs while shining light on design concepts from a more generalized perspective. Since SSSEs are believed to bridge the gap of hitherto known aggregation-sensitive compound classes, we hope to give future scientists a versatile tool in hand to efficiently design novel luminescent materials.

블레이드 동특성 근사모델의 확률 분석을 통한 블레이드 구조 설계

For a rotor system in which the hub/control design and blade OML were determined, the internal structural shape of the blade was designed using the dynamic characteristic surrogate model to maximize the difference between the rotating natural frequency and the integral multiple of the rotational operating frequency. Based on the general blade structure design procedure, an analysis procedure for generating a dynamic characteristic surrogate model was established, and design variables were selected to define the shapes of the internal components. To generate a dynamic characteristic surrogate model, a space filling design method, a type of design of experiment, was applied to generate design variable input values for database configuration. In this process, a range of design variables and constraint conditions suitable for blade design conditions were considered. Based on the analysis results of the finite element 2D sectional properties for various shape input conditions, a 1D beam model dynamic analysis was performed to build a rotation natural frequency database. Using this database, a dynamic characteristic surrogate model for the blade structure design was generated. A regression model and an artificial neural network model were used as surrogate models, and the 1st ~ 4th modes of the blade rotation natural frequency were predicted with the surrogate model and compared with the actual analysis results. Additionally, the values of design variables that can satisfy the dynamic characteristic requirement were selected through probability analysis of the two dynamic characteristic surrogate models, and the accuracy of the predicted values was also confirmed by comparing the analysis results.

Response of Different RC Slab Systems in Buildings to Seismic Excitations

Abstract In the current study, the response of flat, grid and conventional slab against seismic excitation is studied and comparative analysis is performed to establish which among the three slab system would be most effective and safe in an earthquake scenario. The parameter such as storey displacement, drift, shear, and base shear of each slab arrangement is extracted from ETABS which is general structural design software for comparison. In the analysis, three different building specimen with the aforementioned slab type having length, width and height of 40m, 30m and 30m respectively are designed as per Indian design code IS: 456:2000 and analyzed as per IS:1893:2016.

Optimalni projekt drvenih konstrukcija izloženih djelovanju požara uporabom metaheurističkog algoritma

One of the major tasks of structural engineers is to reduce the building cost. Thus, an effective optimization of structural elements is gaining in importance every day. The teaching-learning-based optimization (TLBO), which is one of metaheuristic algorithms, for an optimum design and analysis of timber structures under fire in accordance with EN 1995 1-2 (Eurocode 5: Design of Timber structures - Part 1- 2 General structural fire design), is proposed in this study. The objective function in this algorithm is the building cost of timber structures under fire, considering premature collapse of the structure and limitation of fire spread. A structure made of wood is investigated under different times of fire exposure in order to determine the cross-section and wood type of structural elements. In conclusion, the cross section and strength of structural elements made of wood can be effectively and rapidly optimized with TLBO according to EN 1995 1-2.

Dimerization of sub-nanoscale molecular clusters affords broadly tuneable viscoelasticity above the glass transition temperature.

Materials with promising mechanical performance generally demonstrate requirements for the critical sizes of their key building units, e.g. entanglements and crystal grains. Herein, only with van der Waals interaction, viscoelasticity with broad tunability has been facilely achieved below the critical size limits: the dimers of ∼1 nm polyhedral oligomeric silsesquioxane (POSS) with M w < 4 kD and size < 5 nm, which demonstrate distinct material physics compared to that of polymer nanocomposites of POSS. The dimeric POSSs are confirmed by scattering and calorimetrical measurements to be intrinsic glassy materials with glass transition temperatures (T gs) lower than room temperature. From rheological studies, their viscoelasticity can be broadly tuned through the simple tailoring of the dimer linker structures above their T g. In dimer bulks, each POSS cluster is spatially confined by the POSSs from other dimers and therefore, the correlation of the dynamics of the two linked POSS clusters, which, as indicated by dynamics analysis, is regulated by the length and flexibilities of linkers, contributes to the caging dynamics of POSS confined by their neighbours and the resulting unique viscoelasticity. Our discoveries update the understanding of the structural origin of viscoelasticity and open avenues to fabricate structural materials from the design of sub-nanoscale building blocks.

Realization of Seismic Conceptual Design in General Structure Design

Realization of Seismic Conceptual Design in General Structure Design

Review of Aerodynamic Design Configurations for Wind Mitigation in High-Rise Buildings: Two Cases from Amman

This study is concerned with reviewing and analyzing methods used in early design stages to mitigate wind effects on high-rise buildings. In order to mitigate wind effects on structures and specifically high-rise buildings, early stage aerodynamic design decisions are made. Architects try to mitigate the wind effects on buildings by choosing the right form configuration like tapering or setbacks, etc., or by making vital decisions in the early design stage. However, structural engineers utilize the structural system that can best counter-act forces acting on the stability of the building. For both architects and engineers there are many tools which can be used in early design including advanced analysis methods, wind tunnel testing and wind studies combined with Computational Fluid Dynamics (CFD) simulations. This study reviews general architectural and structural design configurations performed in the early phases of the design process, for achieving structural stability, comfort and cost control. The research methodology depends on the study and analysis of different international building examples, and also by reviewing two local high-rise building cases in Amman, Jordan. The study concludes that there are many architectural aerodynamic configurations for the purpose of mitigating wind loads, which can be used as guidelines in the early design phases.

Numerical Analysis on the Performance of the Underwater Excavation

Based on the Yongdingmen Station of Beijing Metro, the underwater excavation method for deep foundation pit was introduced. This study constructed a numerical analysis model to analyze the performance of surface settlement and lateral wall deflection in the process of underwater excavation. Results showed that this method was better to control the surface settlement and lateral wall deflection compared with other dewatering excavations. In detail, most of the surface settlement was caused during the dry excavation stage and dewatering excavation stage while the deflection caused by underwater excavation only accounted for about 10% of the total settlement. Besides, the maximum settlement occurred 0.25∼0.5 He behind the retaining wall and the value was 0.04% He. Similar to the result of the surface settlement, most of the lateral wall deflection had been completed before the underwater excavation, which only caused about 7% of the total deflection. The maximum wall deflection and its location were approximately 0.06% He and 0.5 He, respectively. Moreover, a series of 3D numerical analyses were studied on the design parameters of the underwater excavation method. This study can be used as a reference for general performance and structural design of foundation pits with underwater excavation.

Automatic structural design of RC wall-slab buildings using a genetic algorithm with application in BIM environment

Abstract This paper proposes an innovative approach based on a genetic algorithm able to automatically derive an optimal structure for a given architectural configuration in IFC format or BIM platform. The concept is based on a multi-objective optimization process that randomly generates an initial population of potential structural configurations which comply with architectural constraints, matching a set of general structural guidelines and seismic design rules. The initial population evolves through series of crossover between current solutions (parent) followed by mutations generating new solutions to be adopted, for the next iteration, when they improve the performance criteria. For illustrative purposes, the proposed methodology is applied to a widely used type of reinforced concrete (RC) wall-slab system for which general structural rules are first elaborated prior to the genetic algorithm implementation. The obtained results have demonstrated that, in the case of the considered architectural configurations, the proposed approach is very efficient in generating optimal structures, which are consistent with the predefined criteria and fulfilling the structural design requirements.

An augmented step size adjustment method for the performance measure approach: Toward general structural reliability-based design optimization

Heavy computational burden has been one of the largest barriers to the application of reliability-based design optimization (RBDO) in real-world structures. The key difficulty of RBDO lies in how to perform reliability analysis efficiently and robustly. In performance measure approach (PMA)-based RBDO, the reliability analysis process searches for the minimum performance target point (MPTP) with the target reliability index in standard normal space. Many methods have been proposed to improve the efficiency and robustness of the PMA. However, these methods may face the convergence problem for highly nonlinear constraint functions; or high computational cost for weakly nonlinear ones. More importantly, most existing methods are very sensitive to the selection of algorithm parameters. In this paper, an augmented step size adjustment (ASSA) method is proposed to boost the iterative process in terms of both efficiency and robustness. According to the relative positions of the direction vector and negative gradient direction and the angle between them at each iterative point, a fire-new strategy is established to identify the oscillation during the iterative process and define the iterative step size. Seven inverse reliability analysis problems and three RBDO benchmarks are used to validate the performance of the ASSA method. The results indicate that the ASSA method has wide applicability for nonlinear constraint functions and achieves efficient and robust performance. Furthermore, the results demonstrate that the ASSA method can be regarded as a reliable and effective method for addressing PMA-based RBDO problems.

Boosting the Stable Na Storage Performance in 1D Oxysulfide

AbstractExploring new structure prototypes and phases by material design, especially anode materials, is essential to develop high‐performance Na‐ion batteries. This study proposes a new anode, Na2Cu2.09O0.50S2, with a 1D crystal structure and outstanding Na storage performance. In view of the crystal structure of Na2Cu2.09O0.50S2, [Cu4S4] chains act as electrically conducting units enabling conductivity as high as 0.5 S cm−1. The residual Na4[CuO] chains act as ionically conducting units forming rich channels for the fast conduction of Na ions as well as maintaining the structural stability even after Na ion extraction. Additional ball milling on the as‐prepared Na2Cu2.09O0.50S2 significantly decreases its grain size, achieving a capacity of 588 mA h g−1 with a high initial Coulombic efficiency of 93% at 0.2 A g−1. Moreover, the Na2Cu2.09O0.50S2 anode demonstrates outstanding rate capability (408 mA h g−1 at 2 A g−1) and extending cyclic performance (82% of capacity retention after 400 cycles). The general structural design idea based on functional units may offer a new avenue to new electrode materials.

Structural development of ultra-lean-burn preburners for small liquid engines

An ultra-lean-burn preburner has been developed by KARI. This paper describes the general structural design, the results of the finite element analyses (FEA) and the experimental results related to structural issues during the development. Before the fabrication, two burst experiments with the specimens simulating the brazing joints were performed and compared with the FEA results, which increases the reliability of the analyses and the design. Also, 2D FEA of the combustion chamber cooling channel were performed for the first combustion region upstream of the liquid oxygen (LOX) hole and the second region downstream of the hole, where the hottest spot locates downstream of the region between the adjacent LOX holes. Various structural modifications were analyzed by 3D FEA and a screen structure was introduced to reduce the stress over highly stressed regions. During the development, some proof and leakage tests were performed for the head, the chamber with and without flange, and the preburner assembly, of which the burst test was performed. Several firing tests of the assembly were performed to show the operation without any structural failure.

Finite Element Analysis for the Lifting Platform of a Self-Propelled Multi-Functional Machine Used in Orchard

Weight reduction is frequently concerned for general structure design as it can save energy in the life cycle of a machine. A small self-propelled multi-functional working machine for orchard use was designed. The lifting platform of the machine is analyzed using the finite element method for the purpose of structure optimization. By carrying out the finite element analysis, the inner stress for each component that forms the lifting platform was discussed under the designed maximum working load. Based on the relationship between the calculated von Mises stress in the structure and the yield strength of the material, the static strength of the component was verified and structure optimization suggestion was given. According to the FEA result, the overall structure of the lifting platform designed on the basis of theoretical calculation is statically safe, except for one of the long shaft sleeve. The dimension for most of the parts should be reduced since these components had an abundant static strength.