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991.
992.
本文指出完全确定序列机状态化简是不完全确定序列机状态化简的特殊情况,后者具有更普遍的意义,文中提出了不完全确定序列机状态化简。 相似文献
993.
利用台湾友晶科技公司的DE10-Lite开发板上的资源,设计简易计算器,来实现4位10进制的加法、减法、乘法运算。利用开发板上十个拨动开关,两个按键开关,六个静态数码管,50MHz信号,通过分层设计,顶层底层相结合,元件调用,实现简易计算的分时显示。 相似文献
994.
Spin glass is the simplest disordered system that preserves the full range of complex collective behavior of interacting frustrating elements. In the paper, we propose a novel approach for calculating the values of thermodynamic averages of the frustrated spin glass model using custom deep neural networks. The spin glass system was considered as a specific weighted graph whose spatial distribution of the edges values determines the fundamental characteristics of the system. Special neural network architectures that mimic the structure of spin lattices have been proposed, which has increased the speed of learning and the accuracy of the predictions compared to the basic solution of fully connected neural networks. At the same time, the use of trained neural networks can reduce simulation time by orders of magnitude compared to other classical methods. The validity of the results is confirmed by comparison with numerical simulation with the replica-exchange Monte Carlo method. 相似文献
995.
Lorenzo Squadrani Nico Curti Enrico Giampieri Daniel Remondini Brian Blais Gastone Castellani 《Entropy (Basel, Switzerland)》2022,24(5)
Purpose: In this work, we propose an implementation of the Bienenstock–Cooper–Munro (BCM) model, obtained by a combination of the classical framework and modern deep learning methodologies. The BCM model remains one of the most promising approaches to modeling the synaptic plasticity of neurons, but its application has remained mainly confined to neuroscience simulations and few applications in data science. Methods: To improve the convergence efficiency of the BCM model, we combine the original plasticity rule with the optimization tools of modern deep learning. By numerical simulation on standard benchmark datasets, we prove the efficiency of the BCM model in learning, memorization capacity, and feature extraction. Results: In all the numerical simulations, the visualization of neuronal synaptic weights confirms the memorization of human-interpretable subsets of patterns. We numerically prove that the selectivity obtained by BCM neurons is indicative of an internal feature extraction procedure, useful for patterns clustering and classification. The introduction of competitiveness between neurons in the same BCM network allows the network to modulate the memorization capacity of the model and the consequent model selectivity. Conclusions: The proposed improvements make the BCM model a suitable alternative to standard machine learning techniques for both feature selection and classification tasks. 相似文献
996.
伴随着薄膜收边机应用范围越来越广,其中涵盖塑料薄膜、纸张、金属化膜等等,其边角料的回收成为了一个热门话题,传统的回收方式严重影响生产效率和高效循环利用,本文介绍了分切收边机通过变频器恒转矩控制加以超高的响应速度,保证了分切收边机在高速快速启停的场合,跟随性能优异,为客户带来了直接的经济收益和生产效率的提高。 相似文献
997.
Although causal inference has shown great value in estimating effect sizes in, for instance, physics, medical studies, and economics, it is rarely used in sports science. Targeted Maximum Likelihood Estimation (TMLE) is a modern method for performing causal inference. TMLE is forgiving in the misspecification of the causal model and improves the estimation of effect sizes using machine-learning methods. We demonstrate the advantage of TMLE in sports science by comparing the calculated effect size with a Generalized Linear Model (GLM). In this study, we introduce TMLE and provide a roadmap for making causal inference and apply the roadmap along with the methods mentioned above in a simulation study and case study investigating the influence of substitutions on the physical performance of the entire soccer team (i.e., the effect size of substitutions on the total physical performance). We construct a causal model, a misspecified causal model, a simulation dataset, and an observed tracking dataset of individual players from 302 elite soccer matches. The simulation dataset results show that TMLE outperforms GLM in estimating the effect size of the substitutions on the total physical performance. Furthermore, TMLE is most robust against model misspecification in both the simulation and the tracking dataset. However, independent of the method used in the tracking dataset, it was found that substitutes increase the physical performance of the entire soccer team. 相似文献
998.
There is great demand for inferring causal effect heterogeneity and for open-source statistical software, which is readily available for practitioners. The mcf package is an open-source Python package that implements Modified Causal Forest (mcf), a causal machine learner. We replicate three well-known studies in the fields of epidemiology, medicine, and labor economics to demonstrate that our mcf package produces aggregate treatment effects, which align with previous results, and in addition, provides novel insights on causal effect heterogeneity. For all resolutions of treatment effects estimation, which can be identified, the mcf package provides inference. We conclude that the mcf constitutes a practical and extensive tool for a modern causal heterogeneous effects analysis. 相似文献
999.
电机作为数控机床的核心部件,其性能影响着机床主轴系统的精度、电机效率和使用寿命.因此,合理设计高速电机的结构使其处于最佳的温度场,了解电机在运行过程中各空气区域内的速度及温度分布非常重要.本文以某机床的电机定转子作为研究对象,利用CFD软件对转子通风道的设计方案进行数值模拟,通过数值模拟分析电机内部的流场温度场及流场分布.根据模拟结果进行优化设计,在转子和定子之间进行单排孔和双排孔的优化方案设计,通过温度分布确定最佳设计方案,为电机转子通风道的散热优化设计提供有意义的参考. 相似文献
1000.
Saad M. Alshahrani Ahmed Al Saqr Munerah M. Alfadhel Abdullah S. Alshetaili Bjad K. Almutairy Amal M. Alsubaiyel Ali H. Almari Jawaher Abdullah Alamoudi Mohammed A. S. Abourehab 《Molecules (Basel, Switzerland)》2022,27(18)
Over the last years, extensive motivation has emerged towards the application of supercritical carbon dioxide (SCCO2) for particle engineering. SCCO2 has great potential for application as a green and eco-friendly technique to reach small crystalline particles with narrow particle size distribution. In this paper, an artificial intelligence (AI) method has been used as an efficient and versatile tool to predict and consequently optimize the solubility of oxaprozin in SCCO2 systems. Three learning methods, including multi-layer perceptron (MLP), Kriging or Gaussian process regression (GPR), and k-nearest neighbors (KNN) are selected to make models on the tiny dataset. The dataset includes 32 data points with two input parameters (temperature and pressure) and one output (solubility). The optimized models were tested with standard metrics. MLP, GPR, and KNN have error rates of 2.079 × 10−8, 2.173 × 10−9, and 1.372 × 10−8, respectively, using MSE metrics. Additionally, in terms of R-squared, they have scores of 0.868, 0.997, and 0.999, respectively. The optimal inputs are the same as the maximum possible values and are paired with a solubility of 1.26 × 10−3 as an output. 相似文献