Residual Method Research Articles

Changes in Vegetation NDVI and Its Response to Climate Change and Human Activities in the Ferghana Basin from 1982 to 2015

Exploring the evolution of vegetation cover and its drivers in the Ferghana Basin helps to understand the current ecological status of the Ferghana Basin and to analyze the vegetation changes and drivers, with a view to providing a scientific basis for regional ecological and environmental management and planning. Based on GIMMS NDVI3g and meteorological data, the spatial and temporal evolution characteristics of NDVI were analyzed from multiple perspectives with the help of linear trend and Mann–Kendall (MK) test methods using arcgis and the R language spatial analysis module, combined with partial correlation coefficients and residual analysis methods to analyze the impacts of climate change and human activities on the regional vegetation cover of the Ferghana Basin from 1982 to 2015. NDVI driving forces. The results showed the following: (1) The growing season of vegetation NDVI in the Ferghana Basin showed an increasing trend in the 34-year period, with an increase rate of 0.0044/10a, and the spatial distribution was significantly different, which was high in the central part of the country and low in the northern and southern parts of the country. (2) Temperature and precipitation simultaneously co-influenced the vegetation NDVI growth season, with most of the temperature and precipitation contributing in the spring, most of the temperature in the summer being negatively phased and the precipitation positively correlated, and most of the temperature and precipitation in the fall inhibiting vegetation NDVI growth. (3) The combined effect of climate change and human activities was the main reason for the overall rapid increase and great spatial variations in vegetation NDVI in China, and the spatial distribution of drivers, namely human activities and climate change, contributed 44.6% to vegetation NDVI in the growing season. The contribution of climate change and human activities to vegetation NDVI in the Ferghana Basin was 62.32% and 93.29%, respectively. The study suggests that more attention should be paid to the role of human activities and climate change in vegetation restoration to inform ecosystem management and green development.

Nanosensors in Pesticide Residue Detection in Grapes

Pesticide residues in grapes pose significant risks to human health and necessitate the development of efficient detection methods to ensure food safety. In recent years, nanosensor technology has emerged as a promising approach for sensitive and reliable pesticide residue detection. This review article provides a comprehensive overview of the recent advancements in nanosensor-based detection methods for pesticide residues in grapes. The article discusses various types of nanosensors employed for pesticide residue detection, including nanostructured materials, nanomaterial-based sensors, and nano biosensors. Nanostructured materials, such as nanoparticles, nanowires, and nanocomposites, offer unique properties that enable high sensitivity and selectivity in detecting pesticide residues. Nanomaterial-based sensors, such as carbon-based, metal-based, and semiconductor-based sensors, provide excellent electrical and optical properties for precise and rapid detection. Furthermore, nano biosensors, including enzymatic and DNA-based sensors, offer specificity and sensitivity through bio-recognition elements. Challenges and future perspectives in the field are discussed, including the standardization and validation of nanosensor-based methods, cost-effectiveness, scalability, integration with portable devices and the Internet of Things (IoT), as well as environmental and regulatory considerations. This review summarizes key findings, discusses the potential impact of nanosensors on the grape industry, and identifies future research directions for further advancement and implementation of nanosensor-based detection methods.

Effect of preoperative alpha-blockers on ureteroscopy outcomes: A meta-analysis of randomised trials.

This work aims to determine the efficacy and safety of preoperative alpha-blocker therapy on ureteroscopy (URS) outcomes. In this systematic review and meta-analysis of randomised trials of URS with or without preoperative alpha-blocker therapy, outcomes included the need for ureteral dilatation, stone access failure, procedure time, residual stone rate, hospital stay, and complications. Residual stone rates were reported with and without adjustments for spontaneous stone passage, medication noncompliance, or adverse events leading to patient withdrawal. Data were analysed using random-effects meta-analysis and meta-regression. Certainty of evidence was assessed using the GRADE criteria. Among 15 randomised trials with 1653 patients, URS was effective and safe with a stone-free rate of 81.2% and rare (2.3%) serious complications. The addition of preoperative alpha-blockers reduced the need for ureteral dilatation (risk ratio [RR] = 0.48; 95% CI = 0.30 to 0.75; p = 0.002), access failure rate (RR = 0.36; 95% CI = 0.23 to 0.57; p < 0.001), procedure time (mean difference [MD] = -6min; 95% CI = -8 to -3; p < 0.001), risk of residual stone in the primary (RR = 0.44; 95% CI = 0.33 to 0.66; p < 0.001) and adjusted (RR = 0.52; 95% CI = 0.40 to 0.68; p < 0.001) analyses, hospital stay (MD = -0.3days; 95% CI = -0.4 to -0.1; p < 0.001), and complication rate (RR = 0.46; 95% CI = 0.35 to 0.59; p < 0.001). Alpha-blockers increased ejaculatory dysfunction risk and were less effective for renal/proximal ureter stones. The certainty of evidence was high or moderate for all outcomes. The main limitation of the review was inconsistency in residual stone assessment methods. While URS is an effective and safe treatment for stone disease, preoperative alpha-blocker therapy is well tolerated and can further improve patient outcomes.

Comparing the performance of two-stage residual inclusion methods when using physician's prescribing preference as an instrumental variable: unmeasured confounding and noncollapsibility.

Aim: The first objective is to compare the performance of two-stage residual inclusion (2SRI), two-stage least square (2SLS) with the multivariable generalized linear model (GLM) in terms of the reducing unmeasured confounding bias. The second objective is to demonstrate the ability of 2SRI and 2SPS in alleviating unmeasured confounding when noncollapsibility exists. Materials & methods: This study comprises a simulation study and an empirical example from a real-world UK population health dataset (Clinical Practice Research Datalink). The instrumental variable (IV) used is based on physicians' prescribing preferences (defined by prescribing history). Results: The percent bias of 2SRI in terms of treatment effect estimates to be lower than GLM and 2SPS and was less than 15% in most scenarios. Further, 2SRI was found to be robust to mild noncollapsibility with the percent bias less than 50%. As the level of unmeasured confounding increased, the ability to alleviate the noncollapsibility decreased. Strong IVs tended to be more robust to noncollapsibility than weak IVs. Conclusion: 2SRI tends to be less biased than GLM and 2SPS in terms of estimating treatment effect. It can be robust to noncollapsibility in the case of the mild unmeasured confounding effect.

Elastic-plastic flexural behavior of hybrid steel girder bridge considering welded residual stress

Hybrid steel girders use a section type that fully utilizes the strength performance of steels, which are widely used in steel plate girder bridges with multiple spans. In this paper, the distribution of the welded residual stress in hybrid I-shaped steel girders was investigated by the hole drilling test, and the unified model was analyzed and revised. Considering welded residual stress, the elastic and plastic design method for calculating the flexural capacity of hybrid I-shaped steel girders was put forward. Experiments and numerical simulations were conducted to analyze the elastic-plastic flexural behavior of the hybrid I-shaped steel girders using multi-scale models. The influence of welded residual stress, geometry of section, steel grade, and initial geometrical imperfections on the elastic-plastic flexural capacity of hybrid I-shaped steel girders were discussed through the parameter analysis adopting the dimensions commonly used in bridges. Analysis results show that the welded residual stress reduces the value of the elastic and plastic bending moments by almost 25% to 40% and 3%, respectively. The geometry of the section should be paid attention to clarify the value of the flexural capacity of the hybrid I-shaped steel girder. The width-to-thickness ratio limit of the flange should be adjusted according to the severity of initial geometrical imperfections.

On the approximations to fractional nonlinear damped Burger’s-type equations that arise in fluids and plasmas using Aboodh residual power series and Aboodh transform iteration methods

Damped Burger’s equation describes the characteristics of one-dimensional nonlinear shock waves in the presence of damping effects and is significant in fluid dynamics, plasma physics, and other fields. Due to the potential applications of this equation, thus the objective of this investigation is to solve and analyze the time fractional form of this equation using methods with precise efficiency, high accuracy, ease of application and calculation, and flexibility in dealing with more complicated equations, which are called the Aboodh residual power series method and the Aboodh transform iteration method (ATIM) within the Caputo operator framework. Also, this study intends to further our understanding of the dynamic characteristics of solutions to the Damped Burger’s equation and to assess the effectiveness of the proposed methods in addressing nonlinear fractional partial differential equations. The two proposed methods are highly effective mathematical techniques for studying more complicated nonlinear differential equations. They can produce precise approximate solutions for intricate evolution equations beyond the specific examined equation. In addition to the proposed methods, the fractional derivatives are processed using the Caputo operator. The Caputo operator enhances the representation of fractional derivatives by providing a more accurate portrayal of the underlying physical processes. Based on the proposed two approaches, a set of approximations to damped Burger’s equation are derived. These approximations are discussed graphically and numerically by presenting a set of two- and three-dimensional graphs. In addition, these approximations are analyzed numerically in several tables, including the absolute error for each approximate solution compared to the exact solution for the integer case. Furthermore, the effect of the fractional parameter on the behavior of the derived approximations is examined and discussed.

Factors associated with dietary iron intakes among pregnant women in Ifako-Ijaiye, Lagos, Nigeria

Iron deficiency anaemia (IDA) in pregnancy is a significant public health problem worldwide, but little is known about factors associated with dietary iron intake among pregnant women especially from low- and middle-income countries(3). This study assessed factors associated with dietary iron intake among pregnant women attending primary health centres in Ifako-Ijaiye Lagos, Nigeria. Sociodemographic information and dietary intakes were elicited from 432 apparently healthy singleton pregnant women using a pre-tested questionnaire and 24 hour- dietary recall, respectively. Dietary iron intakes was estimated from foods and drinks reported using the West African Food Composition Table and adjusted for energy intakes using the residual method(1). Chi-square test and one-way ANOVA was used to compare categorical and continuous variables respectively by tertiles of energy-adjusted dietary iron intakes at a two-sided P&lt;0.05(2).Mean age and dietary iron intake was 28.5 ± 4.6years and 20.3 ± 3.3mg/day, respectively for all respondents. Energy-adjusted iron intakes by tertiles of energy-adjusted dietary intakes were; 16.6 ± 1.4mg/day for the first tertile, 19.7± 1.0mg/day for the second tertile and 23.7 ± 2.0mg/day for the third tertile. Age, gestational age, parity, education, marital status, and income differed insignificantly by tertiles of energy-adjusted dietary iron intakes. Current evidence suggests a statistically insignificant association between sociodemographic factors and dietary iron intakes in this sample, but further studies are vital for designing culturally relevant interventions to promote the consumption of iron-rich foods among women in this population.

Determination of 222 pesticide residues in olive oil by fully automatic QuEChERS pre-treatment instrument coupled with gas chromatography-quadrupole-time-of-flight mass spectrometry

Pesticide residues may be present in olive oil because pesticides are applied to olive trees during their cultivation and growth for pest prevention and some of these pesticides are not easily degraded. Studies on pesticide residues in olive oil have mainly focused on the detection of single types of pesticide residues, and reports on the simultaneous detection of multiple pesticide residues are limited. At present, hundreds of pesticides with different polarities and chemical properties are used in practice. In this study, an analytical method based on fully automatic QuEChERS pretreatment instrument coupled with gas chromatography-quadrupole time-of-flight mass spectrometry (GC-QTOF-MS) was established for the rapid determination of 222 pesticide residues in olive oil. The effects of acetonitrile acidification concentration, n-hexane volume, oscillation time, centrifugation temperature, and purification agent on the determination of the 222 pesticide residues were investigated. First, ions with good responses and no obvious interference were selected for quantification and characterization. The purification process was then developed by setting the parameters of the fully automatic QuEChERS pretreatment instrument to optimal values. The sample was extracted with acetonitrile containing 2% formic acid, and the supernatant was purified by centrifugation in a centrifuge tube containing 400 mg N-propylethylenediamine (PSA), 400 mg octadecylsilane-bonded silica gel (C18), and 1200 mg anhydrous magnesium sulfate. The purified solution was blown dry with nitrogen and then fixed with ethyl acetate for instrumental analysis. Finally, a matrix standard solution was used for quantification. The method was validated in terms of matrix effects, linear ranges, limits of detection (LODs) and quantification (LOQs), accuracies, and precisions. The results showed that 86.04% of the 222 pesticides had linear ranges of 0.02-2.00 μg/mL, 10.81% had linear ranges of 0.10-2.00 μg/mL, and 3.15% had linear ranges of 0.20-2.00 μg/mL. The pesticide residues showed good relationships within their respective linear ranges, and the correlation coefficients (R2) were greater than 0.99. The LODs of all tested pesticides ranged from 0.002 to 0.050 mg/kg, and their LOQs ranged from 0.007 to 0.167 mg/kg. Among the 222 pesticides determined, 170 pesticides had LOQs of 0.007 mg/kg while 21 pesticides had LOQs of 0.017 mg/kg. At the three spiked levels of 0.2, 0.5, and 0.8 mg/kg, 79.58% of all tested pesticides had average recoveries of 70%-120% while 65.92% had average recoveries of 80%-110%. In addition, 93.54% of all tested pesticides had relative standard deviations (RSDs, n=6)<10% while 98.35% had RSDs (n=6)<20%. The method was applied to 14 commercially available olive oil samples, and seven pesticides were detected in the range of 0.0044-0.0490 mg/kg. The residues of fenbuconazole, chlorpyrifos, and methoprene did not exceed the maximum limits stated in GB 2763-2021. The maximum residual limits of molinate, monolinuron, benalaxyl, and thiobencarb have not been established. The method utilizes the high mass resolution capability of TOF-MS, which can improve the detection throughput while ensuring good sensitivity. In addition, high-resolution and accurate mass measurements render the screening results more reliable, which is necessary for the high-throughput detection of pesticide residues. The use of a fully automatic QuEChERS instrument in the pretreatment step reduces personnel errors and labor costs, especially when a large number of samples must be processed, thereby offering significant advantages over other approaches. Moreover, the method is simple, rapid, sensitive, highly automatable, accurate, and precise. Thus, it meets requirements for the high-throughput detection of pesticide residues in olive oil and provides a reference for the development of detection methods for pesticide residues in other types of oils as well as the automatic pretreatment of complex matrices.

Bernstein collocation technique for a class of Sturm-Liouville problems

Sturm-Liouville problems have yielded the biggest achievement in the spectral theory of ordinary differential operators. Sturm-Liouville boundary value issues appear in many key applications in natural sciences. All the eigenvalues for the standard Sturm-Liouville problem are guaranteed to be real and simple, and the related eigenfunctions form a basis in a suitable Hilbert space. This article uses the weighted residual collocation technique to numerically compute the eigenpairs of both regular and singular Strum Liouville problems. Bernstein polynomials over [0,1] has been used to develop a weighted residual collocation approach to achieve an improved accuracy. The properties of Bernstein polynomials and the differentiation formula based on the Bernstein operational matrix are used to simplify the given singular boundary value problems into a matrix-based linear algebraic system. Keeping this fact in mind such a polynomial with space defined collocation scheme has been studied for Strum Liouville problems. The main reasons to use the collocation technique are its affordability, ease of use, well-conditioned matrices, and flexibility. The weighted residual collocation method is found to be more appealing because Bernstein polynomials vanish at the two interval ends, providing better versatility. A multitude of test problems are offered along with computation errors to demonstrate how the suggested method behaves. The numerical algorithm and its applicability to particular situations are described in detail, along with the convergence behavior and precision of the current technique.

Introduction to the Distributional Finite Difference Method for 3D Seismic Wave Propagation and Comparison With the Spectral Element Method

AbstractWe have extended the distributional finite difference method (DFDM) to simulate the seismic‐wave propagation in 3D regional earth models. DFDM shares similarities to the discontinuous finite element method on a global scale and to the finite difference method locally. Instead of using linear staggered finite‐difference operators, we employ DFDM operators based on B‐splines and a definition of derivatives in the sense of distributions, to obtain accurate spatial derivatives. The weighted residuals method used in DFDM's locally weak formalism of spatial derivatives accurately and naturally accounts for the free surface, curvilinear meshing, and solid‐fluid coupling, for which it only requires setting the shear modulus and the continuity condition to zero. The computational efficiency of DFDM is comparable to the spectral element method (SEM) due to the more accurate mass matrix and a new band‐diagonal mass factorization. Numerical examples show that the superior accuracy of the band‐diagonal mass and stiffness matrices in DFDM enables fewer points per wavelength, approaching the spectral limit, and compensates for the increased computational burden due to four Lebedev staggered grids. Specifically, DFDM needs 2.5 points per wavelength, compared to the five points per wavelength required in SEM for 0.5% waveform error in a homogeneous model. Notably, while maintaining the same accuracy in the solid domain, DFDM demonstrates superior accuracy in the fluid domain compared to SEM. To validate its accuracy and flexibility, we present various 3D benchmarks involving homogeneous and heterogeneous regional elastic models and solid‐fluid coupling in both Cartesian and spherical settings.

Goal-adaptive Meshing of Isogeometric Kirchhoff–Love Shells

AbstractMesh adaptivity is a technique to provide detail in numerical solutions without the need to refine the mesh over the whole domain. Mesh adaptivity in isogeometric analysis can be driven by Truncated Hierarchical B-splines (THB-splines) which add degrees of freedom locally based on finer B-spline bases. Labeling of elements for refinement is typically done using residual-based error estimators. In this paper, an adaptive meshing workflow for isogeometric Kirchhoff–Love shell analysis is developed. This framework includes THB-splines, mesh admissibility for combined refinement and coarsening and the Dual-Weighted Residual (DWR) method for computing element-wise error contributions. The DWR can be used in several structural analysis problems, allowing the user to specify a goal quantity of interest which is used to mark elements and refine the mesh. This goal functional can involve, for example, displacements, stresses, eigenfrequencies etc. The proposed framework is evaluated through a set of different benchmark problems, including modal analysis, buckling analysis and non-linear snap-through and bifurcation problems, showing high accuracy of the DWR estimator and efficient allocation of degrees of freedom for advanced shell computations.

Solving the variable coefficient nonlinear partial differential equations based on the bilinear residual network method

Solving the variable coefficient nonlinear partial differential equations based on the bilinear residual network method

Stability analysis of a time-delayed Van der Pol–Helmholtz–Duffing oscillator in fractal space with a non-perturbative approach

The time-delayed fractal Van der Pol–Helmholtz–Duffing (VPHD) oscillator is the subject of this paper, which explores its mechanisms and highlights its stability analysis. While time-delayed technologies are currently garnering significant attention, the focus of this research remains crucially relevant. A non-perturbative approach is employed to refine and set the stage for the system under scrutiny. The innovative methodologies introduced yield an equivalent linear differential equation, mirroring the inherent nonlinearities of the system. Notably, the incorporation of quadratic nonlinearity into the frequency formula represents a cutting-edge advancement. The analytical solution’s validity is corroborated using a numerical approach. Stability conditions are ascertained through the residual Galerkin method. Intriguingly, it is observed that the delay parameter, in the context of the fractal system, reverses its stabilizing influence, impacting both the amplitude of delayed velocity and the position. The analytical solution’s precision is underscored by its close alignment with numerical results. Furthermore, the study reveals that fractal characteristics emulate damping behaviors. Given its applicability across diverse nonlinear dynamical systems, this non-perturbative approach emerges as a promising avenue for future research.

The essentials of the finite element method to solve differential equations: an illustrative case in physics

Here we review the basic steps of the modern and accurate finite element method in its application to solve ordinary differential equations in physics. To exemplify this well-in-vogue numerical technique, we have chosen the second order Poisson-Boltzmann equation, which is a classic equation of colloid science. Aiming to formulate a viable, but didactic, implementation of the finite element technique, we have combined a linear basis of functions, the Galerkin weighted residuals method, the Swartz-Wendroff approximation and the Picard iteration algorithm. In summary, the finite element method transforms a differential equation into a simpler system of algebraic equations for the coefficients of the approximate solution in terms of a set of basis functions. We describe the full computational realisation of the finite element procedure and, also, we examine the corresponding Poisson-Boltzmann numerical predictions for various representative conditions.

Novel enhanced thermal capabilities of Cu-Al2O3/water hybrid nanofluid in an oblique U-shape cavity: On the molecular behaviour through vorticity analysis

This paper presents the numerical investigation of natural convection heat transfer of copper-alumina/pure water hybrid nanofluid in an oblique U-shaped enclosure. The dimensionless governing equation is formed in the stream function-vorticity formulation using dimensionless variables. The Galerkin weighted residual finite element method with the damped Newton-Raphson iteration method is applied to the problem. The heat transfer performance for the system is investigated by varying the Rayleigh numbers, nanoparticle volume fractions and their ratios, and the oblique angles of the enclosure. The fluid flow, heat transfer, and vorticity analysis are conducted extensively for the Rayleigh number up to 106. It was found that the oblique enclosure dwindled the overall heat transfer performance. Correspondingly, the maximum vorticity is at the lowest with zero obliquenesses. The results are used to gain a deeper understanding of the fluid flow and thermal behaviour of the system to achieve more sustainable and greener energy management.

Inverse dynamics analysis of a 6-RR-RP-RR parallel manipulator with offset universal joints

AbstractThis paper presents an algorithm for solving the inverse dynamics of a parallel manipulator (PM) with offset universal joints (RR–joints) via the Newton–Euler method. The PM with RR–joints increase the joint stiffness and enlarge the workspace but introduces additional joint parameters and constraint torques, rendering the dynamics more complex. Unlike existing studies on PMs with RR–joints, which emphasize the kinematics and joint performance, this paper studies the dynamical model. First, an iterative algorithm is established through a rigid body velocity transformation, which calculates the input parameters of the link velocity and acceleration. A linear system of equations in matrix form is then established for the entire PM through the Newton–Euler method. By using the generalized minimal residual method (GMRES) to solve the equation system, all the forces and torques on the joints can be obtained, from which the required actuation force can be derived. This method is validated through numerical simulations using the automatic dynamic analysis of multibody systems software. The proposed method is suitable for establishing the dynamic model of complex PMs with redundant or hybrid structures.

Determination of abamectin in food based on magnetic covalent organic frameworks and HPLC-FLD

Abamectin is widely applied in agriculture and aquaculture, easily accumulates through the food chain and endangers human health. Sample pretreatment is the crucial and fundamental procedure prior to the precise analysis of trace abamectin. Herein, 4,4',4''-(1,3,5-triazine-2,4,6-triyl) trianiline (Tz) and 2,5-dihydroxy-1,4-benzenedicarboxaldehyde (Da) were modified on the surface of Fe3O4 nanoparticles to prepare magnetic covalent organic frameworks (Fe3O4@TzDa) adsorbent for abamectin. Depending on the large specific surface of TzDa and hydrogen bonding, π-π and hydrophobic interactions between TzDa and abamectin, the efficient magnetic solid-phase extraction (MSPE) of abamectin residue was achieved. Under the optimal MSPE conditions, the developed MSPE-HPLC-FLD based on Fe3O4@TzDa method for abamectin residue afforded good linearity (0.05–500 μg L−1) with high R2 (0.998) and low limit of detection (0.015 μg L−1). The developed MSPE-HPLC method was evaluated and successfully applied to determine abamectin residue in lake water, milk and peach juice samples with satisfactory recoveries (87.1–119.1%) and relative standard deviations (1.9–4.9%).

Can Technological Advancements be Effective for the Economic Value of the Companies? Insights from the DSE Listed Food and Allied Companies

Purposes: Adopting technology in the production process increases the overall efficiency of inputs used in the production, and enhances a firm's economic value. Methodology: This study tries to explore the impact of technology on firm performance from 8 listed Food and Allied companies spanning 2015-2021 listed on DSE. Total factor productivity (TFP) is an inclusive measure that apprehends the contribution of all aspects that improve the efficiency of production including technology. Therefore, the contribution of technical advancement to the firm is captured by TFP, applying the Solow residual method. TFP is the main study variable and some other control variables, such as tangibility, liquidity, firm size, and growth; long-term leverage ratio and net debt tax shield are used as exogenous variables to increase the robustness of the model and improve the value of both the firm performance ROA and ROE. Results: Finally, this study concluded that investment in technology in the food and allied sectors has a notable impact on a firm’s performance. Therefore, the study indicates that economists, policymakers, and business management can use TFP growth as an indicator for making their long-term decision policy and increase the overall sustainable economic productivity, growth and efficiency of the firm and can contribute to accelerating the economic growth of the country.

Finite element boundary element numerical simulation study on acoustic vibration coupling problems

Excessive structural resonance response in the acoustic vibration coupling environment can cause adverse consequences such as structural damage, local instability, and component failure. Accurately predicting the vibration response of instruments under external sound fields helps to avoid structural performance degradation or damage caused by vibration, and ensures the reliability and safety of the system, which is of great significance for the effective load of instrument equipment. This paper constructs a finite element boundary element equation for the acoustic vibration coupling problem, and adopts a series of optimization measures for it. In response to the low computational efficiency of finite element boundary element equations and their inability to meet the computational requirements of complex models, this paper introduces the acoustic vibration reciprocity theorem and the fast directional boundary element method to compensate for the aforementioned shortcomings. In addition, the study used the weighted residual method to construct a data exchange algorithm to ensure energy conservation during the transfer process. The research focuses on typical structures of spacecraft and conducts simulation analysis and application research on acoustic vibration coupling problems. The simulation showcases that the introduction of the reciprocity theorem markedly reduces the calculation time and memory occupied by the equation, with a required calculation time of 1.23 h and a data file size of approximately 299.56 MB generated by the calculation; The overall error of the data exchange process is below 10−4. Scanning frequency analysis is conducted on the surface and local openings of the model structure, and it is found that the displacement of the selected excitation point is in good agreement with the analytical solution. This study effectively reduces simulation time and memory requirements through the proposed strategy, ensures energy conservation data exchange algorithms, improves the reliability and safety of structural design, and has important practical value for evaluating the structural performance of key equipment such as spacecraft.

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