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关键词： 降雨量   空间插值   空间自相关   交叉检验   恩施  

摘要： 针对地形复杂多变的恩施地区单一空间插值方法不总适应的问题,提出了一种针对恩施地区的分区方案和各区独立插值的方法。采用分而治之的策略解决了恩施地区降雨插值误差最小的优化问题,较好地平衡了地形异质性与降雨自相关性之间的矛盾,并依据与降雨密切相关的高程因子对恩施地区实现了剖分;基于划分的子区域,采用均方根误差为各子区域筛选出最优的插值方法,实现分区的个性化插值。实验结果表明:此方法不仅能减小子区域地形异质性,降低地形因子对降雨插值的影响,还能找出适用于恩施地区分区插值的最优方案。研究结果可以应用于气温、湿度、PM2.5等具有局地适用性的空间插值领域。

关键词： 岩棉板   保温   施工技术   质量控制  

摘要： 在建筑的施工过程中,应用外墙保温的施工工艺能够巩固和改善建筑本身的隔热作用,在目前的建筑施工中,随着岩棉板外保温技术的不断发展,岩棉板外保温技术的应用日益广泛。本文从建筑外保温工程的技术水平出发,进行了建筑外保温工程的岩棉板技术水平、关于操作的必要性等问题的探讨,合理地整合有关的施工技术等,并对外墙保温施工质量控制的主要内容进行了阐述。加强对外墙保温施工的质量与效果,希望通过分析能对我国建筑外保温工程进行有益的探索。

关键词： 水库大坝   稳定性   施工方式   比选  

摘要： 水库大坝的稳定是维持水库正常运营的重要安全保障,以石门子水库大坝加固工程为背景,通过数值模拟对大坝加固过程中的施工方式进行比选优化,得出以下结论:按坡比1∶2、1∶2.5、1∶3起坡进行反压加固后,新坝体的安全系数与未加固前相比,分别降低约80.11%、77.79%及77.69%;当填筑速率为0.5 m/d、1.0 m/d、2.0 m/d时,与未加固前相比,新坝体安全系数降低幅度分别约为78.42%、83.17%、86.14%;当平台间距为0.5 m、1.0 m、1.5 m时,与无平台相比,坝体安全系数分别提高约33.33%、43.21%、53.18%;综合考虑施工周期、成本及安全性,坡比1∶2、填筑速率1.0 m/d、平台间距0.5 m为最优施工方式。

关键词： 人造板许可证   监督检查   人造板性能参数  

摘要： 为了基层检查人员应对人造板生产许可证的现场监督检查,本文综述了人造板类产品生产许可监督检查的依据,指出了检查中涉及的主要技术标准。通过对人员、设备、质量体系管控和施工工艺质量参数等方面技术要点的阐述,说明了现场监督抽查应该注意的问题。为人造板类产品生产许可证监督检查提供了技术指引和必要支撑。

关键词： MATLAB  

摘要： In this paper, the thermal conductivity (knf) of the Al2O3/Ethylene Glycol -Water nanofluid is measured. MATLAB software is used to fit a nonlinear function, and the analysis of variance (ANOVA) is implemented to determine the effect of temperature and volume fraction of nanoparticles (φ) on extracting the residuals and knf. In the experimental part, various combinations of temperatures (from 30 to 60 °C) and volume fractions (fromφ = 0.15 up to 1.3%) are examined, and then the obtained data are analyzed using MINITAB software. The results show that the knf is highly dependent on φ and less dependent on temperature. By changing the φ from 0.15 to 1.3%, the thermal conductivity increases around 40%. In contrast, increasing the temperature from 30 to 60 °C will increase the knf by almost 10%. Also, the results show that the thermal conductivity slope is lower at φ © 2024

关键词： MATLAB  

摘要： The distillation tower is a crucial component of the refining process. Its energy efficiency has been a major area of research, especially following the oil crisis. This study focuses on optimizing energy consumption in the Shiraz refinery’s distillation unit. The unit is simulated using ASPEN-HYSYS software. Simulation results are validated against real data to ensure model accuracy. The operational data aligns well with model predictions. Following the creation of a data bank using HYSYS software, the tower’s operating conditions are optimized using neural networks and MATLAB software. In this study, a neural network model is developed for the distillation tower. This modeling approach is cost-effective, does not require complex theories, and does not rely on prior system knowledge. Additionally, real-time modeling is achievable through parallel distributed processing. The findings indicate that the optimal feed tray is 9 and the optimal feed temperature is 283.5°C. Furthermore, the optimized number of trays in the distillation tower is 47. Results show that in optimal conditions, cold and hot energy consumption are reduced by approximately 9.7% and 10.8%, respectively. Moreover, implementing optimal conditions results in a reduction of hot energy consumption in the reboiler by 60,000 MW and a reduction of cold energy consumption in the condenser by 30,000 MW. © The Author(s), under exclusive licence to Springer-Verlag London Ltd., part of Springer Nature 2024.

关键词： Site-effect   H/V spectral ratio   Seismic exploration   Ambient seismic noise   Diffuse field  

摘要： The relationship between the horizontal-to-vertical spectral ratio of ambient seismic noise and the elastic Green's function has been established based on the principles of seismic interferometry. We have developed HV-Inv, , a software designed in MATLAB for the forward and inverse calculations of the Horizontal-to-Vertical spectral ratio of ambient seismic noise (H/V) under the theory of diffuse fields. HV-Inv features both global and local inversion methods, supporting the simultaneous inversion of Rayleigh and Love wave dispersion curves with H/V. The goal is for it to bean effective tool for passive seismic exploration.

关键词： Register Transfer Level-Software Defined Radio   Speech/Music classification   Real-time system   Multimedia signal processing   EFFICIENT IMPLEMENTATION   SPEECH/MUSIC CLASSIFIER   MUSIC   DISCRIMINATION   FEATURES   TRACKING  

摘要： This work introduces a real-time system to automate the selection of radio stations based on the listener's preference (either speech/music) by analyzing the incoming audio signals using a speech/music classifier (SMC) using machine learning approaches. Radio Frequency data from different Frequency Modulated (FM) stations are directly read in MATLAB using the Communications Toolbox Support Package for Register Transfer Level-Software Defined Radio (RTL-SDR). Further, the work is divided into two phases. Initially, the efficiency of different state-of-the-art features for designing a speech/music classifier is studied on new speech/music corpora developed for Indian radio stations. Box plots and Region of Convergence (ROC) plots were used to study feature importance. The learning from the experiments was used to select optimum sets of features for efficient working of the real-time model. The models were tested for both offline and online test data. The best-performing features (Mel-Frequency Cepstral Coefficients (MFCC) + Variance Spectral Roll-off) vectors were then concatenated to obtain the best classification accuracy of 93.06% and 83.91% for offline and realtime data, respectively, using Gaussian Mixture Model (GMM) classifier. We also studied the efficiency of recently proposed Empirical Mode decomposition (EMD)-based statistical and Hilbert Spectrum-based features on both standard (Slaney, GTZAN, Musan dataset) and newly created datasets. We achieved an overall accuracy of 94.91%, 93.20%, 91.72%, and 95.40% for SS, GTZAN, MUSAN, and BITM datasets respectively. However, concatenating several features increased the latency of the algorithm. This work also proposes a new speech/music corpus based on recordings from Indian radio stations in the Hindi language.

关键词： MATLAB  

摘要： This manuscript merits at examining of an embedded orthogonal plate inside porous domain exposed to uniform heat influx to elaborate on how micro polar fluid factors and permeability characteristic affect the local skin friction, heating rate, and angular velocity inside boundary layer. The plate is subjected to forced convective micro polar fluid influx under steady, incompressible, and viscous circumstances. To facilitate dependable numerical solution, similarity approach is implemented to mutate set of coupled governing equations relevant to the adopted study into a constrained dimensionless differential equations. Computational analysis has been executed hiring Runge-Kutta scheme by Matlab function bvp4c to settle the governing equations. Study's results are highlighted graphically the impact of micro polar fluid factors on the local skin friction, heating rate, and angular velocity curves. High degree of acceptability of present findings compare with prior research results. It is found that the rising of Darcy parameter drives to decrease linearly both heating rate and local skin friction. Among the examined factors, the benchmark parameter of decreasing skin friction is the porosity. Additionally, it is found that an increasing of Prandtl number and micro rotation element lead to enhance Nusselt number. Once curves of micro rotation are interfered at certain distance from the plate due to increase in porosity, Darcy, Forchheimer's, and microelement rotation, the micro rotation curves are inverted. © 2024

关键词： Three-dimensional cutting   Mesh   Joints   Convex body   NUMERICAL MANIFOLD   FINITE-ELEMENT   IDENTIFICATION   REFINEMENT   STABILITY   SYSTEM  

摘要： This study presents a simple approach and its associated MATLAB toolbox for 3D block cutting and mesh cutting. The approach is suitable for the meshes of numerical methods including the Key Block Theory (KBT), the Discontinuous Deformation Analysis (DDA), the Numerical Manifold Method (NMM), and the cut Finite Element Method (Cut-FEM). The strategy is based on calculations on convex bodies. It uses two different forms of representation: the geometric representation which includes vertices and faces, and the algebraic representation which consists of inequalities. The cutting was implemented on the algebraic representation, and the resulting inequalities were converted into a geometric representation. The above strategy turned out to be robust and straightforward to execute, at the cost of a general body being regarded as a combination of convex bodies. The efficiency guarantee was considered through pre-checking algorithms. The source code was provided, as well as some simple examples.