Real-Time Spreading Thickness Monitoring of High-core Rockfill Dam Based on K-nearest Neighbor Algorithm

During the storehouse surface rolling construction of a core rockfilldam, the spreading thickness of dam face is an important factor that affects the construction quality of the dam storehouse' rolling surface and the overallquality of the entire dam. Currently, the method used to monitor and controlspreading thickness during the dam construction process is artificialsampling check after spreading, which makes it difficult to monitor the entire dam storehouse surface. In this paper, we present an in-depth study based on real-time monitoring and controltheory of storehouse surface rolling construction and obtain the rolling compaction thickness by analyzing the construction track of the rolling machine. Comparatively, the traditionalmethod can only analyze the rolling thickness of the dam storehouse surface after it has been compacted and cannot determine the thickness of the dam storehouse surface in realtime. To solve these problems, our system monitors the construction progress of the leveling machine and employs a real-time spreading thickness monitoring modelbased on the K-nearest neighbor algorithm. Taking the LHK core rockfilldam in Southwest China as an example, we performed real-time monitoring for the spreading thickness and conducted real-time interactive queries regarding the spreading thickness. This approach provides a new method for controlling the spreading thickness of the core rockfilldam storehouse surface.

Wireless Communication Signal Strength Prediction Method Based on the K-nearest Neighbor Algorithm

Existing interference protection systems lack automatic evaluation methods to provide scientific, objective and accurate assessment results. To address this issue, this paper develops a layout scheme by geometrically modeling the actual scene, so that the hand-held full-band spectrum analyzer would be able to collect signal field strength values for indoor complex scenes. An improved prediction algorithm based on the K-nearest neighbor non-parametric kernel regression was proposed to predict the signal field strengths for the whole plane before and after being shield. Then the highest accuracy set of data could be picked out by comparison. The experimental results show that the improved prediction algorithm based on the K-nearest neighbor non-parametric kernel regression can scientifically and objectively predict the indoor complex scenes’ signal strength and evaluate the interference protection with high accuracy.

Enhancing Cancer Classification through a Hybrid Bio-Inspired Evolutionary Algorithm for Biomarker Gene Selection

In this study,our aim is to address the problem of gene selection by proposing a hybrid bio-inspired evolutionary algorithm that combines Grey Wolf Optimization(GWO)with Harris Hawks Optimization(HHO)for feature selection.Themotivation for utilizingGWOandHHOstems fromtheir bio-inspired nature and their demonstrated success in optimization problems.We aimto leverage the strengths of these algorithms to enhance the effectiveness of feature selection in microarray-based cancer classification.We selected leave-one-out cross-validation(LOOCV)to evaluate the performance of both two widely used classifiers,k-nearest neighbors(KNN)and support vector machine(SVM),on high-dimensional cancer microarray data.The proposed method is extensively tested on six publicly available cancer microarray datasets,and a comprehensive comparison with recently published methods is conducted.Our hybrid algorithm demonstrates its effectiveness in improving classification performance,Surpassing alternative approaches in terms of precision.The outcomes confirm the capability of our method to substantially improve both the precision and efficiency of cancer classification,thereby advancing the development ofmore efficient treatment strategies.The proposed hybridmethod offers a promising solution to the gene selection problem in microarray-based cancer classification.It improves the accuracy and efficiency of cancer diagnosis and treatment,and its superior performance compared to other methods highlights its potential applicability in realworld cancer classification tasks.By harnessing the complementary search mechanisms of GWO and HHO,we leverage their bio-inspired behavior to identify informative genes relevant to cancer diagnosis and treatment.

A Study of EM Algorithm as an Imputation Method: A Model-Based Simulation Study with Application to a Synthetic Compositional Data

Compositional data, such as relative information, is a crucial aspect of machine learning and other related fields. It is typically recorded as closed data or sums to a constant, like 100%. The statistical linear model is the most used technique for identifying hidden relationships between underlying random variables of interest. However, data quality is a significant challenge in machine learning, especially when missing data is present. The linear regression model is a commonly used statistical modeling technique used in various applications to find relationships between variables of interest. When estimating linear regression parameters which are useful for things like future prediction and partial effects analysis of independent variables, maximum likelihood estimation (MLE) is the method of choice. However, many datasets contain missing observations, which can lead to costly and time-consuming data recovery. To address this issue, the expectation-maximization (EM) algorithm has been suggested as a solution for situations including missing data. The EM algorithm repeatedly finds the best estimates of parameters in statistical models that depend on variables or data that have not been observed. This is called maximum likelihood or maximum a posteriori (MAP). Using the present estimate as input, the expectation (E) step constructs a log-likelihood function. Finding the parameters that maximize the anticipated log-likelihood, as determined in the E step, is the job of the maximization (M) phase. This study looked at how well the EM algorithm worked on a made-up compositional dataset with missing observations. It used both the robust least square version and ordinary least square regression techniques. The efficacy of the EM algorithm was compared with two alternative imputation techniques, k-Nearest Neighbor (k-NN) and mean imputation (), in terms of Aitchison distances and covariance.

A Memetic Algorithm With Competition for the Capacitated Green Vehicle Routing Problem

In this paper, a memetic algorithm with competition(MAC) is proposed to solve the capacitated green vehicle routing problem(CGVRP). Firstly, the permutation array called traveling salesman problem(TSP) route is used to encode the solution, and an effective decoding method to construct the CGVRP route is presented accordingly. Secondly, the k-nearest neighbor(k NN) based initialization is presented to take use of the location information of the customers. Thirdly, according to the characteristics of the CGVRP, the search operators in the variable neighborhood search(VNS) framework and the simulated annealing(SA) strategy are executed on the TSP route for all solutions. Moreover, the customer adjustment operator and the alternative fuel station(AFS) adjustment operator on the CGVRP route are executed for the elite solutions after competition. In addition, the crossover operator is employed to share information among different solutions. The effect of parameter setting is investigated using the Taguchi method of design-ofexperiment to suggest suitable values. Via numerical tests, it demonstrates the effectiveness of both the competitive search and the decoding method. Moreover, extensive comparative results show that the proposed algorithm is more effective and efficient than the existing methods in solving the CGVRP.

An Improved Whale Optimization Algorithm for Feature Selection

Whale optimization algorithm(WOA)is a new population-based meta-heuristic algorithm.WOA uses shrinking encircling mechanism,spiral rise,and random learning strategies to update whale’s positions.WOA has merit in terms of simple calculation and high computational accuracy,but its convergence speed is slow and it is easy to fall into the local optimal solution.In order to overcome the shortcomings,this paper integrates adaptive neighborhood and hybrid mutation strategies into whale optimization algorithms,designs the average distance from itself to other whales as an adaptive neighborhood radius,and chooses to learn from the optimal solution in the neighborhood instead of random learning strategies.The hybrid mutation strategy is used to enhance the ability of algorithm to jump out of the local optimal solution.A new whale optimization algorithm(HMNWOA)is proposed.The proposed algorithm inherits the global search capability of the original algorithm,enhances the exploitation ability,improves the quality of the population,and thus improves the convergence speed of the algorithm.A feature selection algorithm based on binary HMNWOA is proposed.Twelve standard datasets from UCI repository test the validity of the proposed algorithm for feature selection.The experimental results show that HMNWOA is very competitive compared to the other six popular feature selection methods in improving the classification accuracy and reducing the number of features,and ensures that HMNWOA has strong search ability in the search feature space.

Research on Initialization on EM Algorithm Based on Gaussian Mixture Model

The EM algorithm is a very popular maximum likelihood estimation method, the iterative algorithm for solving the maximum likelihood estimator when the observation data is the incomplete data, but also is very effective algorithm to estimate the finite mixture model parameters. However, EM algorithm can not guarantee to find the global optimal solution, and often easy to fall into local optimal solution, so it is sensitive to the determination of initial value to iteration. Traditional EM algorithm select the initial value at random, we propose an improved method of selection of initial value. First, we use the k-nearest-neighbor method to delete outliers. Second, use the k-means to initialize the EM algorithm. Compare this method with the original random initial value method, numerical experiments show that the parameter estimation effect of the initialization of the EM algorithm is significantly better than the effect of the original EM algorithm.

基于融合K-近邻算法的电压互感器在线监测方法

由于受工作时长和环境因素的影响,电容式电压互感器(capacitor voltage transformer,CVT)在运行过程中误差稳定性不高,易出现电能计量失准现象。为此,该文提出了一种基于融合K-近邻算法(fusion K-nearest neighbor algorithm,FKNN)的电压互感器在线评估方法。该方法利用互感器的历史运行数据构建虚拟标准器,通过改进K-近邻算法对互感器实时状态进行监测,实现对异常情况的报警。同时,提出了一种加权移动时间窗的方法,自适应更新异常阈值,有效削弱电网不平衡波动的影响。实验结果表明,该文方法能够准确监测互感器的0.2级误差漂移。

基于多策略融合斑马优化算法的特征选择方法

针对传统斑马优化算法在求解复杂优化问题时精度低、收敛速度慢和易陷入局部最优的不足,提出一种多策略融合的改进斑马优化算法(IZOA)。首先,为解决斑马个体初始位置分布不均匀的问题,引入混沌映射来增加探索过程的种群多样性;其次,受自适应权重和黄金正弦算法思想启发,提出一种基于自适应递减权重和黄金正弦更新机制的位置更新策略,用于改进斑马算法的局部寻优与全局探索能力;然后,进行标准测试函数实验,验证了IZOA能够有效提升寻优精度和收敛速度;最后,将K近邻分类器作为待优化目标,选取UCI库的12个标准数据集进行特征选择实验,并利用改进后的算法在特征选择模型中进行最优特征子集搜寻。实验结果表明,相比传统算法,所提算法的平均分类准确率提升4.47%,平均适应度值降低2.5%,验证了该算法在特征选择领域的优越性。

Rapid prediction of flow and concentration fields in solid-liquid suspensions of slurry electrolysis tanks

Slurry electrolysis(SE),as a hydrometallurgical process,has the characteristic of a multitank series connection,which leads to various stirring conditions and a complex solid suspension state.The computational fluid dynamics(CFD),which requires high computing resources,and a combination with machine learning was proposed to construct a rapid prediction model for the liquid flow and solid concentration fields in a SE tank.Through scientific selection of calculation samples via orthogonal experiments,a comprehensive dataset covering a wide range of conditions was established while effectively reducing the number of simulations and providing reasonable weights for each factor.Then,a prediction model of the SE tank was constructed using the K-nearest neighbor algorithm.The results show that with the increase in levels of orthogonal experiments,the prediction accuracy of the model improved remarkably.The model established with four factors and nine levels can accurately predict the flow and concentration fields,and the regression coefficients of average velocity and solid concentration were 0.926 and 0.937,respectively.Compared with traditional CFD,the response time of field information prediction in this model was reduced from 75 h to 20 s,which solves the problem of serious lag in CFD applied alone to actual production and meets real-time production control requirements.

自适应邻域密度聚类及事故黑点识别应用

聚类作为识别交通事故黑点的主要方法之一,其主要问题是交通事故多发区事先无法确定,即无法提前知道聚类簇数。利用样本点之间的连接概率定义了数据点的局部密度,根据局部密度大小来确定聚类中心和簇数,再对数据点进行聚类。结果表明:一是算法对参数不敏感,具有较好的通用性;二是算法能自动确定聚类簇数;三是算法聚类过程只依赖局部密度与邻接点,能够识别噪声点,提升结果的准确性。运用算法在一些真实数据集上进行试验,将聚类结果与其他算法结果利用评价指标ARI(Adjusted Rand Index)和NMI(Normalized Mutual Information)进行比较。最后利用算法对美国6个州的交通事故进行聚类,结果表明算法对交通事故有较好的适应性,能将城市及周边道路上事故密集区域准确识别出来。

基于自适应近邻信息的模糊C均值聚类算法

传统的模糊C均值算法直接基于原始数据进行聚类,数据的内在结构可能会被噪声、异常值或其他因素破坏,因此聚类性能会受到影响。为提升FCM算法的鲁棒性,提出了一种基于自适应近邻信息的模糊C均值聚类算法。近邻信息指的是一种基于数据点之间相似度的度量,每个数据点都可以看作其他数据点的近邻,但是不同数据点之间的相似度是不同的。将样本点的近邻信息GX和类中心点的近邻信息GV融入基础FCM模型中,为聚类过程提供更多的数据结构信息,用于指导聚类算法中的簇划分过程,以提升算法的稳定性,并提出了3个迭代算法求解本文提出的聚类模型。与其他先进聚类算法对比,在部分基准数据集上聚类性能有10%以上的提升,同时还从参数敏感性、收敛性、消融实验等方面对算法进行评价。实验结果可以充分显示本文提出的聚类算法的可行性与有效性。

Adaptive Fault Detection Scheme Using an Optimized Self-healing Ensemble Machine Learning Algorithm

This paper proposes a new cost-efficient,adaptive,and self-healing algorithm in real time that detects faults in a short period with high accuracy,even in the situations when it is difficult to detect.Rather than using traditional machine learning(ML)algorithms or hybrid signal processing techniques,a new framework based on an optimization enabled weighted ensemble method is developed that combines essential ML algorithms.In the proposed method,the system will select and compound appropriate ML algorithms based on Particle Swarm Optimization(PSO)weights.For this purpose,power system failures are simulated by using the PSCA D-Python co-simulation.One of the salient features of this study is that the proposed solution works on real-time raw data without using any pre-computational techniques or pre-stored information.Therefore,the proposed technique will be able to work on different systems,topologies,or data collections.The proposed fault detection technique is validated by using PSCAD-Python co-simulation on a modified and standard IEEE-14 and standard IEEE-39 bus considering network faults which are difficult to detect.

自适应确定DBSCAN算法参数的算法研究

传统DBSCAN算法需要人为确定Eps和MinPts参数,参数的选择直接决定了聚类结果的合理性,因此提出一种新的自适应确定DBSCAN算法参数算法,该算法基于参数寻优策略,通过利用数据集自身分布特性生成候选Eps和MinPts参数,自动寻找聚类结果的簇数变化稳定区间,并将该区间中密度阈值最少时所对应的Eps和MinPts参数作为最优参数。实验结果表明,该算法能够实现聚类过程的全自动化并且能够选择合理的Eps和MinPts参数,得到了高准确度聚类结果。

RFID技术的定位改进算法在铁路隧道人员定位中的应用

本文介绍无线射频识别技术(RFID)的基本原理,重点阐述基于RFID的LANDMARC定位算法的原理与过程。在此基础上,综合考虑铁路隧道内折射、反射、多径效应等因素对场强的影响,分析LANDMARC定位算法的不足,将此算法进行改进,提出自适应LANDMARC k-邻居算法,结合RF Code公司的硬件系统,将其应用到铁路隧道人员定位系统中。实验证明改进的算法具有更高的定位精度:定位精度在1m以内的标签占70%,比原来算法的60%提高10%;93%的标签定位误差小于1.5m,且最大误差控制在2.5m以内。对提高隧道内人员的安全管理水平具有重要意义。

K近邻的自适应谱聚类快速算法

谱聚类算法建立在谱图划分理论基础上,与传统的聚类算法相比,它具有能在任意形状的样本空间上聚类且收敛于全局最优解的优点。然而,谱聚类算法涉及如何选取合适的尺度参数σ构造相似度矩阵的问题。并且,在处理大规模数据集时,聚类的过程需要较大的时间和内存开销。研究从构造相似度矩阵入手,以传统NJW算法为基础,提出一种基于K近邻的自适应谱聚类快速算法FA-SC。该算法能自动确定尺度参数σ;同时,对输入数据集分块处理,并用基于K近邻的稀疏相似度矩阵保存样本信息,减少计算的内存开销,提高了运行速度。通过实验,与传统谱聚类算法比较,FA-SC算法在人工数据集和UCI数据集上能够取得更好的聚类效果。

一种基于邻居自适应的多目标元胞遗传算法

针对现有多目标元胞遗传算法存在邻居单一固定、不能适时变化的缺点,提出一种基于邻居自适应的多目标元胞遗传算法。该算法在经典多目标元胞遗传算法的基础上引入邻居自适应机制,动态调节邻居结构,使算法不断寻找全局搜索与局部寻优之间的平衡点。最后,与现有流行的其他多目标进化算法作比较,通过对不同类型的20种基准测试函数问题进行测试,证明该算法具有良好的收敛性和扩展性。

求解TSP问题的自适应邻域遗传算法

提出结合自适应邻域法与遗传算法来求解TSP问题。在自适应邻域法中,从某个城市出发,下一城市不一定是其最近城市,而是在比其最近城市稍远的邻域范围进行动态随机选取。在求解TSP时,采用自适应邻域法对种群初始化,然后采用选择、交叉、变异进行迭代,在选择中仅保留父代90%的样本,剩下的采用自适应邻域法产生新样本进行补充。仿真实验结果表明所提算法与其他算法相比具有竞争能力。

一种基于自适应最近邻的聚类融合方法

聚类融合通过把具有一定差异性的聚类成员进行组合,能够得到比单一算法更为优越的结果,是近年来聚类算法研究领域的热点问题之一。提出了一种基于自适应最近邻的聚类融合算法ANNCE,能够根据数据分布密度的不同,为每一个数据点自动选择合适的最近邻选取范围。该算法与已有的基于KNN的算法相比,不仅解决了KNN算法中存在的过多参数需要实验确定的问题,还进一步提高了聚类效果。

基于自适应烟花算法和k近邻算法的特征选择算法

特征选择是从原始特征集中选取若干个特征子集,并降低数据维度和减少冗余信息,从而达到提高分类准确度的效果。为了达到此效果,将自适应烟花算法进行离散化处理,使用k近邻算法作为分类器,并提出新的特征选择算法。将特征子集引入目标函数,并使用惩罚因子来处理约束条件,采用十折交叉验证法来检验分类效果。使用机器学习常用的UCI数据集进行仿真实验,结果表明:与增强烟花算法、烟花算法、蝙蝠算法、粒子群算法和自适应粒子群算法相比,该算法的性能更优。