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Healthcare is evolving from standard to personalized, driven by the patients' needs. Personalized healthcare is a medical model based on genetics, genomics, and other biological information that helps to predict risk for disease. To date, machine learning and data mining are the fastest-growing healthcare field used to classify patient cohorts from a large dataset and its application for diabetes subtyping will be a breakthrough. In this review paper, we have identified, analyzed, and summarized how previous studies distinguished diabetes into subtypes besides implementing the methods for diabetes subtyping using data mining and various clustering algorithms. We have discovered that many studies have suggested diabetes can be differentiated into subtypes clinically based on the risk complications, genetically defined, using clinical features, and for treatment selection. As for clustering algorithms, k-means clustering and hierarchical clustering were shown to be widely used in determining sub-clusters of diabetes. To further investigate diabetes subtyping, understanding the specific objective and method of diabetes subtyping using clustering algorithms from a large dataset will be crucial which could contribute to novel knowledge and improvement for diabetes management. [ABSTRACT FROM AUTHOR]

Software is playing a growing role in many safety-critical applications, and software systems dependability is a major concern. Predicting faulty modules of software before the testing phase is one method for enhancing software reliability. The ability to predict and identify the faulty modules of software can lower software testing costs. Machine learning algorithms can be used to solve software fault prediction problem. Identifying the faulty modules of software with the maximum accuracy, precision, and performance are the main objectives of this study. A hybrid method combining the autoencoder and the K-means algorithm is utilized in this paper to develop a software fault predictor. The autoencoder algorithm, as a preprocessor, is used to select the effective attributes of the training dataset and consequently to reduce its size. Using an autoencoder with the K-means clustering method results in lower clustering error and time. Tests conducted on the standard NASA PROMIS data sets demonstrate that by removing the inefficient elements from the training data set, the proposed fault predictor has increased accuracy (96%) and precision (93%). The recall criteria provided by the proposed method is about 87%. Also, reducing the time necessary to create the software fault predictor is the other merit of this study. [ABSTRACT FROM AUTHOR]

Recently, Internet of Things (IoT) and multimedia are gaining popularity because of their usages in various applications. Numerous sensors and automated devices are generating huge volumes of data. Therefore, it is required to efficiently and effectively analyze this voluminous data. It can be achieved by using appropriate machine leaning techniques such as clustering. Among the clustering techniques, the k-means method/algorithm is one of the simplest, effective and commonly used methods. For making the cluster, it uses a measure of similarity/distance among the data observations. Nearby/similar data observations are placed within the same cluster whereas distant/dis-similar data observations are placed in other clusters. Hence, the similarity/distance metric plays a major role on the performance and accuracy of the k-means. Therefore, using an appropriate similarity/distance metric, the performance and accuracy of the k-means can be improved. K-means algorithm is majorly implemented using Euclidean distance metric. With the objective to explore the better and/or alternate similarity/distance metric(s) for k-means, a case study, based on empirical evaluation, of thirteen different similarity/distance metrics on six well-known datasets is performed and presented in this paper. By using the efficient and effective similarity / distance metrics, the performance and accuracy of the k-means algorithm can be improved which leads to formation of good clusters of various data observations or things or images etc. The results of the empirical study are analyzed and compared on the basis of widely used statistical clustering evaluation/validation measures. Based on the comparative results, these metrics are assigned with the ranks. Overall, the results demonstrate that Manhattan and Minkowski distance metrics gives better results for k-means algorithm. [ABSTRACT FROM AUTHOR]

An asymmetric approach to clustering of the asymmetric self-organizing map is proposed. The clustering is performed using an improved asymmetric version of the well-known $$k$$ -means algorithm. The improved asymmetric $$k$$ -means algorithm is the second proposal of this paper. As a result, we obtain a two-stage fully asymmetric data analysis technique. In this way, we maintain the methodological consistency of the both utilized methods, because they are both formulated in asymmetric versions, and consequently, they both properly adjust to asymmetric relationships in analyzed data. The results of our experiments on real data confirm the effectiveness of the proposed approach. [ABSTRACT FROM AUTHOR]

With the many folds increase in demand for capacity in mobile broadband communication technology every year, wireless carriers must be prepared for the tremendous increase in mobile traffic in coming years. It forces scientists and researchers to come up with new wireless spectrum bands which has capabilities to support higher data rates. The higher spectrum bands like millimeter waves are the candidate band for this type of problems. This band comes with the challenges of radio wave attenuations oof signals due to the presence of gases, water vapor and other weather phenomenon like rain, storms, snow, hail etc. Different models are presented in order to predict attenuation due to rain out of which ITU-R model is the widely acceptable model. The ITU-R model contains complex methodology for calculating regression coefficients which are depends on frequency and polarization. In this paper, K-Means algorithm is used to propose an improved ITU-R model. Proposed model can make up the shortcoming of ITU-R model to determine the break-up points in frequency range and obtained soft clusters have been trained by machine learning algorithms then proposes a mathematical model for prediction of radio wave attenuation due to rain. The implementation results of proposed model were also compared with the ITU-R model. [ABSTRACT FROM AUTHOR]

Inferring the quality of service experienced by wireless users is challenging, as network monitoring does not capture the service perception for each user individually. In this paper, we propose an unsupervised machine learning approach to infer the quality of service experienced by wireless users, based on the different usage profiles of a large-scale wireless network. To this end, our approach correlates the usage data of access points, and the summaries of connection flows passing through the access points in the network. Then, we apply the k-means clustering algorithm to infer different network usage profiles. We evaluate our proposed approach to infer QoS on a real large-scale wireless network, and the results show that discriminating the flows into five clusters allows identifying prevalent usage profiles of the degraded state of the network and overload conditions in access points, considering only the flow summaries. [ABSTRACT FROM AUTHOR]

This paper proposes a novel method for finding interesting behaviour in complex systems based on compression. A new clustering algorithm has been designed and applied specifically for clustering 1D elementary cellular automata behaviour using the prediction by partial matching (PPM) compression scheme, with the results gathered to find interesting behaviours. This new algorithm is then compared with other clustering algorithms in Weka and the new algorithm is found to be more effective at grouping behaviour that is visually similar in output. Using PPM compression, the rate of change of the cross-entropy with respect to time is calculated. These values are used in combination with a clustering algorithm, such as k-means, to create a new set of clusters for cellular automata. An analysis of the data in each cluster is then used to determine if a cluster can be classed as interesting. The clustering algorithm itself was able to find unusual behaviours, such as rules 167 and 181 which have output that is slightly different from all the other Sierpiński Triangle-like patterns, because their apexes are off-centre by one cell. When comparing the new algorithm with other established ones, it was discovered that the new algorithm was more effective in its ability to group interesting and unusual cellular automata behaviours together. [ABSTRACT FROM AUTHOR]

The global k-means algorithm is an incremental approach to clustering that dynamically adds one cluster center at a time through a deterministic global search procedure from suitable initial positions, and employs k-means to minimize the sum of the intra-cluster variances. However the global k-means algorithm sometimes results singleton clusters and the initial positions sometimes are bad, after a bad initialization, poor local optimal can be easily obtained by k-means algorithm. In this paper, we modified the global k-means algorithm to eliminate the singleton clusters at first, and then we apply MinMax k-means clustering error method to global k-means algorithm to overcome the effect of bad initialization, proposed the global Minmax k-means algorithm. The proposed clustering method is tested on some popular data sets and compared to the k-means algorithm, the global k-means algorithm and the MinMax k-means algorithm. The experiment results show our proposed algorithm outperforms other algorithms mentioned in the paper. [ABSTRACT FROM AUTHOR]

With the rapid increase of user access, load balancing in cloud data center has become an important factor affecting cluster stability. From the point of view of green scheduling, this paper proposed a virtual machine intelligent scheduling strategy based on machine learning algorithm to achieve load balancing of cloud data center. Firstly, a load forecasting algorithm based on genetic algorithm (SVR_GA), k-means clustering algorithm based on optimized min-max, and adaptive differential evolution algorithm (ESA_DE) to enhance local search ability are proposed to solve the load imbalance problem in cloud data center. The experimental results showed that compared with other classical algorithms, the proposed virtual machine scheduling strategy reduces the number of virtual machine migration by 94.5% and the energy consumption of cloud data center by 49.13%. [ABSTRACT FROM AUTHOR]

Evolutionary K-Means (EKM), which combines K-Means and genetic algorithm, solves K-Means' initiation problem by selecting parameters automatically through the evolution of partitions. Currently, EKM algorithms usually choose silhouette index as cluster validity index, and they are effective in clustering well-separated clusters. However, their performance of clustering noisy data is often disappointing. On the other hand, clustering stability-based approaches are more robust to noise; yet, they should start intelligently to find some challenging clusters. It is necessary to join EKM with clustering stability-based analysis. In this paper, we present a novel EKM algorithm that uses clustering stability to evaluate partitions. We firstly introduce two weighted aggregated consensus matrices, positive aggregated consensus matrix (PA) and negative aggregated consensus matrix (NA), to store clustering tendency for each pair of instances. Specifically, PA stores the tendency of sharing the same label and NA stores that of having different labels. Based upon the matrices, clusters and partitions can be evaluated from the view of clustering stability. Then, we propose a clustering stability-based EKM algorithm CSEKM that evolves partitions and the aggregated matrices simultaneously. To evaluate the algorithm's performance, we compare it with an EKM algorithm, two consensus clustering algorithms, a clustering stability-based algorithm and a multi-index-based clustering approach. Experimental results on a series of artificial datasets, two simulated datasets and eight UCI datasets suggest CSEKM is more robust to noise. [ABSTRACT FROM AUTHOR]

Because of its deterministic nature, K-means does not yield confidence information about centroids and estimated cluster memberships, although this could be useful for inferential purposes. In this paper we propose to arrive at such information by means of a non-parametric bootstrap procedure, the performance of which is tested in an extensive simulation study. Results show that the coverage of hyper-ellipsoid bootstrap confidence regions for the centroids is in general close to the nominal coverage probability. For the cluster memberships, we found that probabilistic membership information derived from the bootstrap analysis can be used to improve the cluster assignment of individual objects, albeit only in the case of a very large number of clusters. However, in the case of smaller numbers of clusters, the probabilistic membership information still appeared to be useful as it indicates for which objects the cluster assignment resulting from the analysis of the original data is likely to be correct; hence, this information can be used to construct a partial clustering in which the latter objects only are assigned to clusters. [ABSTRACT FROM AUTHOR]

Brain tumour is a fatal disease and its diagnosis is a difficult procedure for radiologists due to the heterogeneous behaviour of tumour cells. Diagnosing brain tumour using MRI at early stage is essential by attaining higher accuracy with minimum error function. Based on this insight, the goal of the proposed research is to create a deep learning architecture that will aid in the automatic detection of brain tumour utilising two-dimensional MRI slices. The proposedSquare Array Filtering(SAF) approach is applied to the acquired input image in order to remove such noisy contents. To obtain a noiseless image, an array in square grid format is generated to update the missing pixel values of an image using SAF. This research employs the Kernel K-means clustering (K2C) model for segmenting the injured region, with the weighted mean enhancement methodology efficiently removing noise from the image and the K2C method isolating the infected areas. The proposed Optimization empowered Hierarchical Residual VGGNet19 (HR-VGGNet19) model is designed to explore the discriminative information with the help of convolution layer employed in it. The proposed model combines both the low level and high-level features with the help of HR-VGGNet19 network and obtains the output class. The performance metric shows the proposed methodology outperforms better than the state-of-art methods. The proposed methodology is implemented in the working platform of MATLAB in terms of evaluation metrics like accuracy, sensitivity, specificity, PPV, NPV, FPR, FNR and FDR. [ABSTRACT FROM AUTHOR]

Data obtained from additive manufactured components can be analyzed to gain a better understanding of the manufacturing physics and to improve the quality of the parts. However, additive manufacturing is a complex process with many sensitivities. Machine learning has recently been used in additive manufacturing to model and evaluate processes. It is not possible to provide a single regression model to predict mechanical behavior as the properties will vary based on the component geometry and in regions within a component. To provide a separate regression model for each region, it is better to categorize several regions for multiple geometries by their post- fabrication properties (maximum and minimum principal stresses and distortion). Clustering is a method for analyzing the quality of parts with similar characteristics in diverse areas. Twenty-three distinct geometries with numerous geometric characteristics, each experiencing a different history of heat during fabrication (due to their thickness and material distribution), are analyzed in this study. Three different clustering methods are employed (self-organizing map, k-means clustering, and fuzzy c-means clustering). The results are presented in two parts. For the first case, a localized approach is taken, where a comprehensive data set is utilized. The observed maximum coefficient of variance is 0.07969. For the second case, each shape is considered as an instance (sample) with general geometric characteristics. Similar trends between different clustering methods were extracted for the global approach, highlighting the potential of this method, but the clustering results are dependent on the clustering method. According to these results, the analysis of the local data provides a deeper understanding of post-fabrication properties clustering. Additional geometric-based characteristics will be developed to refine and improve the global approach. [ABSTRACT FROM AUTHOR]

The k-means algorithm is widely used for clustering, compressing, and summarizing vector data. We present a fast and memory-efficient GPU-based algorithm for exact k-means, Asynchronous Selective Batched K-means (ASB K-means). Unlike most GPU-based k-means algorithms that require loading the whole dataset onto the GPU for clustering, the amount of GPU memory required to run our algorithm can be chosen to be much smaller than the size of the whole dataset. Thus, our algorithm can cluster datasets whose size exceeds the available GPU memory. The algorithm works in a batched fashion and applies the triangle inequality in each k-means iteration to omit a data point if its membership assignment, i.e., the cluster it belongs to, remains unchanged, thus significantly reducing the number of data points that need to be transferred between the CPU's RAM and the GPU's global memory and enabling the algorithm to very efficiently process large datasets. Our algorithm can be substantially faster than a GPU-based implementation of standard k-means even in situations when application of the standard algorithm is feasible because the whole dataset fits into GPU memory. Experiments show that ASB K-means can run up to 15x times faster than a standard GPU-based implementation of k-means, and it also outperforms the GPU-based k-means implementation in NVIDIA's open-source RAPIDS machine learning library on all the datasets used in our experiments. [ABSTRACT FROM AUTHOR]

A wireless sensor network is a potential technique which is most suitable for continuous monitoring applications where the human intervention is not possible. It employs large number of sensor nodes, which will perform various operations like data gathering, transmission and forwarding. An optimal Q-learning based clustering and load balancing technique using improved K-Means algorithm is proposed. It contains two phases namely clustering phase and node balancing phase. The proposed algorithm uses Q-learning technique for deploying sensor nodes in appropriate clusters and cluster head CH election. In the clustering phase, the node will be placed in appropriate clusters based on the computation of the mean values. Once the sensors are placed in an appropriate cluster, then the cluster will be divided into 'k' partitions. The node which is having maximum residual energy in each partition will be elected as the partition head PH. In node balancing phase, the number of sensors in each partition will be evenly distributed by considering the area of the cluster and the number of sensors inside the cluster. Among the PHs, the node which is having residual energy to the maximum and also having the minimal distance to the sink is elected as the CH. The residual energy of the CH is monitored periodically. If it falls below the threshold level, then another partition head PH which is having residual energy to the maximum level and possessing minimum distance to the sink node will be elected as CH. The proposed Q-Learning based clustering technique maximize the reward by considering the throughput, end-to-end delay, packet delivery ratio and energy consumption. Finally, the performance of the Q-learning based clustering algorithm is evaluated and compared existing k-means based clustering algorithms. Our results indicate that the proposed method reduces end to end delay by 8.23%, throughput is increased by 2.34%, network lifetime is increased by 3.34%, packet delivery ratio is improved by 1.56%. [ABSTRACT FROM AUTHOR]