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EN
Machine learning-based classification algorithms allow communication and computing (2C) task allocation to network edge servers. This article considers poisoning of classifiable 2C data features in two scenarios: noise-like jamming and targeted data falsification. These attacks have a fatal effect on classification in the feature areas with unclear decision boundary. We propose training and noise detection using the Silhouette Score to detect and mitigate attacks. We demonstrate effectiveness of our methods.
PL
Algorytmy klasyfikacji oparte na uczeniu maszynowym umożliwiają zoptymalizowaną alokację zadań telekomunikacyjnych i obliczeniowych (2C) do serwerów brzegowych sieci. W artykule omówiono ataki zatruwające, które mają negatywny wpływ na klasyfikację zadań 2C w obszarach, w których granica decyzyjna jest niejasna. Proponujemy metodę trenowania modelu oraz wykorzystanie testu Silhouette do wykrywania i unikania ataków. Wykazujemy skuteczność tych metod wobec rozważanych ataków.
EN
This paper proposes a zone-based three-level heterogeneous clustering protocol (ZB-TLHCP) for heterogeneous WSNs. In ZB-TLHCP, the sensor field/region is divided into zones where super, advance, and normal nodes are deployed uniformly and randomly. The performance of the proposed ZB-TLHCP system is compared with that of zonal-stable election protocol (Z-SEP), distributed energy efficient clustering (DEEC), and threshold-based DEEC (TDEEC) protocol by varying the number of super and advance nodes, their energy levels for the fixed sensor field, and the total number of nodes. Matlab simulation results revealed that the proposed ZB-TLHCP solution performed better than Z-SEP, DEEC, and TDEEC protocols, as it increased the instability period, prolonged the network's lifetime, and achieved higher throughput values.
EN
Software defined networking (SDN) is an emerging network paradigm that separates the control plane from data plane and ensures programmable network management. In SDN, the control plane is responsible for decision-making, while packet forwarding is handled by the data plane based on flow entries defined by the control plane. The placement of controllers is an important research issue that significantly impacts the performance of SDN. In this work, we utilize clustering techniques to group networks into multiple clusters and propose an algorithm for optimal controller placement within each cluster. The evaluation involves the use of the Mininet emulator with POX as the SDN controller. By employing the silhouette score, we determine the optimal number of controllers for various topologies. Additionally, to enhance network performance, we employ the meeting point algorithm to calculate the best location for placing the controller within each cluster. The proposed approach is compared with existing works in terms of throughput, delay, and jitter using six topologies from the Internet Zoo dataset.
EN
The study aimed to evaluate the soil environmental characteristics of Vinh Long Province’s perennial crop-growing area using principal component analysis (PCA) and cluster analysis (CA). Soil environmental quality data were collected in eight districts of Vinh Long province for 27 physical and chemical parameters. CA and PCA analysis was used to group and identify critical parameters affecting perennial crops’ soil environment. The findings demonstrate low to moderate soil compaction porosity, buffering capacity, and structure for perennial crops. In addition, the soil has a low pH, electrical conductivity, total soluble salts, aluminum, and cation exchange capacity. Although rich in nutrients, the content of organic matter, available phosphorus, cations, and trace elements is only low to moderate. CA results showed three districts suitable for strongly developing perennial crops: Tra On, Mang Thit, and Vung Liem. The PCA results showed that except for density, the buffer capacity of the soil, and dissolved Al3+, the upcoming monitoring program must incorporate all remaining criteria. The study’s findings offer crucial information to help the management organization devise strategies for enhancing and sustainably expanding perennial crops in the province. It is necessary to further evaluate the soil’s environmental quality over time and soil depth and determine the frequency of monitoring in the study area.
EN
Cluster analysis can be defined as applying clustering algorithms with the goalof finding any hidden patterns or groupings in a data set. Different clusteringmethods may provide different solutions for the same data set. Traditionalclustering algorithms are popular, but handling big data sets is beyond theabilities of such methods. We propose three big data clustering methods basedon the firefly algorithm (FA). Three different fitness functions were definedon FA using inter-cluster distance, intra-cluster distance, silhouette value, andthe Calinski-Harabasz index. The algorithms find the most appropriate clustercenters for a given data set. The algorithms were tested with nine popularsynthetic data sets and one medical data set and are later applied on two bad-minton data sets with the intention of identifying the different playing stylesof players based on their physical characteristics. The results specify that thefirefly algorithm could generate better clustering results with high accuracy.The algorithms cluster the players to find the most suitable playing strategyfor a given player where expert knowledge is needed in labeling the clusters.Comparisons with a PSO-based clustering algorithm (APSO) and traditional al-gorithms point out that the proposed firefly variants work in a similar fashion asthe APSO method, and they surpass the performance of traditional algorithms.
EN
Most of the wireless sensor networks (WSNs) used in healthcare and security sectors are affected by the battery constraints, which cause a low network lifetime problem and prevents these networks from achieving their maximum performance. It is anticipated that by combining fuzzy logic (FL) approximation reasoning approach with WSN, the complex behavior of WSN will be easier to handle. In healthcare, WSNs are used to track activities of daily living (ADL) and collect data for longitudinal studies. It is easy to understand how such WSNs could be used to violate people’s privacy. The main aim of this research is to address the issues associated with battery constraints for WSN and resolve these issues. Such an algorithm could be successfully applied to environmental monitoring for healthcare systems where a dense sensor network is required and the stability period should be high.
7
Content available K-means is probabilistically poor
EN
Kleinberg introduced the concept of k-richness as a requirement for an algorithm to be a clustering algorithm. The most popular algorithm k means dos not fit this definition because of its probabilistic nature. Hence Ackerman et al. proposed the notion of probabilistic k-richness claiming without proof that k-means has this property. It is proven in this paper, by example, that the version of k-means with random initialization does not have the property probabilistic k-richness, just rebuking Ackeman's claim.
EN
Internet of Things (IoT) is the new research paradigm which has gained a great significance due to its widespread applicability in diverse fields. Due to the open nature of communication and control, the IoT network is more susceptible to several security threats. Hence the IoT network requires a trust aware mechanism which can identify and isolate the malicious nodes. Trust Sensing has been playing a significant role in dealing with security issue in IoT. A novel a Light Weight Clustered Trust Sensing (LWCTS) model is developed which ensures a secured and qualitative data transmission in the IoT network. Simulation experiments are conducted over the proposed model and the performance is compared with existing models. The obtained results prove the effectiveness when compared with existing approaches.
EN
Wireless sensor network (WSN) is assortment of sensor nodes proficient in environmental information sensing, refining it and transmitting it to base station in sovereign manner. The minute sensors communicate themselves to sense and monitor the environment. The main challenges are limited power, short communication range, low bandwidth and limited processing. The power source of these sensor nodes are the main hurdle in design of energy efficient network. The main objective of the proposed clustering and data transmission algorithm is to augment network performance by using swarm intelligence approach. This technique is based on K-mean based clustering, data rate optimization using firefly optimization algorithm and Ant colony optimization based data forwarding. The KFOA is divided in three parts: (1) Clustering of sensor nodes using K-mean technique and (2) data rate optimization for controlling congestion and (3) using shortest path for data transmission based on Ant colony optimization (ACO) technique. The performance is analyzed based on two scenarios as with rate optimization and without rate optimization. The first scenario consists of two operations as k-mean clustering and ACO based routing. The second scenario consists of three operations as mentioned in KFOA. The performance is evaluated in terms of throughput, packet delivery ratio, energy dissipation and residual energy analysis. The simulation results show improvement in performance by using with rate optimization technique.
EN
This paper is devoted to topical issues - the development of methods for analyzing texture images of breast cancer. The main problem that is resolved in the article is that the requirements for the results of pre-processing are increasing. As a result of the task, images of magnetic resonance imaging of the breast are considered for image processing using texture image analysis methods. The main goal of the research is the development and implementation of algorithms that allow detecting and isolating a tumor in the breast in women in an image. To solve the problem, textural features, clustering, orthogonal transformations are used. The methods of analysis of texture images of breast cancer, carried out in the article, namely: Hadamard transform, oblique transform, discrete cosine transform, Daubechies transform, Legendre transform, the results of their software implementation on the example of biomedical images of oncological pathologies on the example of breast cancer, it is shown that The most informative for image segmentation is the method based on the Hadamard transform and the method based on the Haar transform. The article presents recommendations for using the results in practice, namely, it is shown that clinically important indicators that make a significant contribution to assessing the degree of pathology and the likelihood of developing diseases, there are other information parameters: diameter, curvature, etc. Therefore, increased requirements for the reliability, accuracy, speed of processing biomedical images.
PL
Niniejszy artykuł jest poświęcony aktualnemu tematowi - opracowaniu metod analizy obrazów tekstury raka piersi. Główny problem, który został rozwiązany w artykule, polega na tym, że wymagania wobec wyników przetwarzania wstępnego są coraz większe. W wyniku realizacji zadania rozpatrzono obrazy rezonansu magnetycznego piersi przeznaczone do przetwarzania metodami teksturowej analizy obrazu. Głównym celem badań jest opracowanie i wdrożenie algorytmów wykrywania i odróżniania na obrazie guza w piersi u kobiet. Do rozwiązania tego problemu wykorzystuje się cechy tekstury, grupowanie i transformacje ortogonalne. W artykule przedstawiono metody analizy obrazów teksturowych raka piersi, t j. transformatę Adamarda, transformatę skośną, transformatę dyskretno-cosinusową, transformatę Dobeshiego, transformatę Lejandre'a, oraz wyniki ich implementacji programowej na przykładzie obrazów biomedycznych patologii onkologicznej w przypadku raka piersi. Metoda oparta na transformacie Adamarda oraz metoda oparta na transformacie Haara są najbardziej przydatne do segmentacji obrazów. W artykule przedstawiono zalecenia dotyczące wykorzystania wyników w praktyce, a mianowicie wykazano, że inne parametry informacyjne, takie jak średnica, krzywizna itp. są ważnymi klinicznie wskaźnikami, które w istotny sposób przyczyniają się do oceny stopnia patologii i prawdopodobieństwa rozwoju choroby. W związku z tym wzrastają wymagania dotyczące niezawodności, dokładności i szybkości przetwarzania obrazów biomedycznych w urządzeniach diagnostycznych.
11
EN
In this paper, experimental data, given in the form of pairwise comparisons, such as distances or similarities, are considered. Clustering algorithms for processing such data are developed based on the well-known k-means procedure. Relations to factor analysis are shown. The problems of improving clustering quality and of finding the proper number of clusters in the case of pairwise comparisons are considered. Illustrative examples are provided.
12
Content available Bank Loan Analysis using Data Mining Techniques
EN
Nowadays, a bank loan can provide people with cash to fund home improvements or start a business. However, some customers who are accepted with a loan cannot repay or someone usually repays in a delayed time. Therefore, to minimize losses, examining loan applications is particularly evident for the bank. This paper study on bank loan analysis using data mining techniques. We use association rules mining, clustering, and classification techniques on the applicant's profile to help the bank quickly decide for a loan applicant.
PL
Rozpatrywany jest problem wyznaczania rekomendacji na podstawie wskazanych przykładów decyzji akceptowalnych i przykładów decyzji nieakceptowalnych. Wskazanie przez decydenta tych przykładów jest podstawą oceny jego preferencji. Istota przedstawionego rozwiązania polega na określeniu preferencji jako klastra wyznaczonego poprzez uzupełnianie wskazanych przykładów. W artykule zaproponowano procedurę kolejnych przybliżeń bazującą na rozwiązaniach zadania klasyfikacji na podstawie zadanych przykładów.
EN
The problem of determining a decision recommendation according to examples of acceptable decisions and examples of unacceptable decisions indicated by the decision-maker is considered in the paper. The decision-maker's examples are the foundation for assessing his preferences. The essence of the presented solution consists in determining the preferences of the decision-maker as a cluster designated by supplementing the indicated examples. The paper proposes a procedure of successive approximations based on the classification task according to given examples.
EN
The article is devoted to substantiating the expediency of reorienting international investment flows, under the influence of the COVID-19 pandemic, from traditional directions to projects related to social transformation. It is proved that such transformations should be expressed first of all in qualitative changes in education, medicine and employment. Particular attention is paid to the modernization of the paradigm of sustainable development, the components of which should be ranked from social to environmental. The necessity of interpretation of investment strategies implemented in the countries following their common problems is substantiated. Also, attention is paid to the substantiation of the cyclical component, its role in the redistribution of investment flows at the state level. The article proposed cluster investment to solve this problem.
PL
Artykuł poświęcony jest uzasadnieniu celowości przeorientowania międzynarodowych przepływów inwestycyjnych pod wpływem pandemii COVID-19 z tradycyjnych kierunków na projekty związane z transformacją społeczną. Udowodniono, że takie przemiany powinny wyrażać się przede wszystkim w jakościowych zmianach w edukacji, medycynie i zatrudnieniu. Szczególną uwagę zwraca się na unowocześnienie paradygmatu zrównoważonego rozwoju, którego elementy należy uszeregować od społecznych do środowiskowych. Uzasadniono konieczność interpretacji strategii inwestycyjnych realizowanych w krajach podążających za wspólnymi problemami. Zwrócono również uwagę na uzasadnienie składnika cyklicznego, jego rolę w redystrybucji przepływów inwestycyjnych na poziomie państwa. W celu rozwiązania tego problemu w artykule zaproponowano inwestycje w klastry.
EN
Assessment of seismic vulnerability of urban infrastructure is an actual problem, since the damage caused by earthquakes is quite significant. Despite the complexity of such tasks, today’s machine learning methods allow the use of “fast” methods for assessing seismic vulnerability. The article proposes a methodology for assessing the characteristics of typical urban objects that affect their seismic resistance; using classification and clustering methods. For the analysis, we use kmeans and hkmeans clustering methods, where the Euclidean distance is used as a measure of proximity. The optimal number of clusters is determined using the Elbow method. A decision-making model on the seismic resistance of an urban object is presented, also the most important variables that have the greatest impact on the seismic resistance of an urban object are identified. The study shows that the results of clustering coincide with expert estimates, and the characteristic of typical urban objects can be determined as a result of data modeling using clustering algorithms.
EN
The Internet of Vehicles (IoVs) has become a vital research area in order to enhance passenger and road safety, increasing traffic efficiency and enhanced reliable connectivity. In this regard, for monitoring and controlling the communication between IoVs, routing protocols are deployed. Frequent changes that occur in the topology often leads to major challenges in IoVs, such as dynamic topology changes, shortest routing paths and also scalability. One of the best solutions for such challenges is “clustering”. This study focuses on IoVs’ stability and to create an efficient routing protocol in dynamic environment. In this context, we proposed a novel algorithm called Cluster-based enhanced AODV for IoVs (AODV-CD) to achieve stable and efficient clustering for simplifying routing and ensuring quality of service (QoS). Our proposed protocol enhances the overall network throughput and delivery ratio, with less routing load and less delay compared to AODV. Thus, extensive simulations are carried out in SUMO and NS2 for evaluating the efficiency of the AODV-CD that is superior to the classic AODV and other recent modified AODV algorithms.
EN
Wireless sensor network is a dynamic field of networking and communication because of its increasing demand in critical Industrial and Robotics applications. Clustering is the technique mainly used in the WSN to deal with large load density for efficient energy conservation. Formation of number of duplicate clusters in the clustering algorithm decreases the throughput and network lifetime of WSN. To deal with this problem, advance distributive energy-efficient adaptive clustering protocol with sleep/wake scheduling algorithm (DEACP-S/W) for the selection of optimal cluster head is presented in this paper. The presented sleep/wake cluster head scheduling along with distributive adaptive clustering protocol helps in reducing the transmission delay by properly balancing of load among nodes. The performance of algorithm is evaluated on the basis of network lifetime, throughput, average residual energy, packet delivered to the base station (BS) and CH of nodes. The results are compared with standard LEACH and DEACP protocols and it is observed that the proposed protocol performs better than existing algorithms. Throughput is improved by 8.1% over LEACH and by 2.7% over DEACP. Average residual energy is increased by 6.4% over LEACH and by 4% over DEACP. Also, the network is operable for nearly 33% more rounds compared to these reference algorithms which ultimately results in increasing lifetime of the Wireless Sensor Network.
18
EN
A linear combination of Gaussian components is known as a Gaussian mixture model. It is widely used in data mining and pattern recognition. In this paper, we propose a method to estimate the parameters of the density function given by a Gaussian mixture model. Our proposal is based on the Gini index, a methodology to measure the inequality degree between two probability distributions, and consists in minimizing the Gini index between an empirical distribution for the data and a Gaussian mixture model. We will show several simulated examples and real data examples, observing some of the properties of the proposed method.
EN
A variety of clustering validation indices (CVIs) are aimed at validating the results of clustering analysis and determining which clustering algorithm performs best. Different validation indices may be appropriate for different clustering algorithms or partition dissimilarity measures; however, the best suitable index to use in practice remains unknown. A single CVI is generally unable to handle the wide variability and scalability of the data and cope successfully with all the contexts. Therefore, one of the popular approaches is to use a combination of multiple CVIs and fuse their votes into the final decision. This work aims to analyze the majority-based decision fusion method. Thus, the experimental work consisted of designing and implementing the NbClust majority-based decision fusion method and then evaluating the CVIs performance with different clustering algorithms and dissimilarity measures to discover the best validation configuration. Moreover, the authors proposed to enhance the standard majority-based decision fusion method with straightforward rules for the maximum efficiency of the validation procedure. The result showed that the designed enhanced method with an invasive validation configuration could cope with almost all data sets (99%) with different experimental factors (density, dimensionality, number of clusters, etc.).
PL
Różnorodne indeksy walidacji klasteryzacji (CVI) mają na celu walidację wyników analizy skupień i określenie, który algorytm klasteryzacji działa najlepiej. Różne indeksy walidacji mogą być odpowiednie dla różnych algorytmów klasteryzacji lub miar niepodobieństwa podziału; jednak najlepszy walidacyjny indeks do zastosowania w praktyce pozostaje nieznany. Pojedynczy CVI na ogół nie jest w stanie poradzić sobie z dużą zmiennością i skalowalnością danych oraz z powodzeniem poradzić sobie we wszystkich kontekstach. Dlatego jednym z popularnych podejść jest użycie kombinacji wielu CVIs i połączenie ich głosów w ostateczną decyzję. Celem tej pracy jest analiza metody fuzji decyzji opartej na większości. W związku z tym prace eksperymentalne polegały na zaprojektowaniu i wdrożeniu metody NbClust fuzji decyzji opartej na większości, a następnie ocenianie wydajności CVIs za pomocą różnych algorytmów klasteryzacji i miar niepodobieństwa w celu odkrycia najlepszej konfiguracji walidacji. Ponadto autor zaproponował rozszerzenie standardowej metody fuzji decyzji oparta na większości o proste reguły dla maksymalnej efektywności procedury walidacji. Wynik pokazał, że zaprojektowana ulepszona metoda z inwazyjną konfiguracją walidacji może poradzić sobie z prawie wszystkimi zbiorami danych (99%) z różnymi eksperymentalnymi parametrami (gęstość, wymiarowość, liczba klastrów itp.).
20
Content available remote Image retrieval of MRI brain tumour images based on SVM and FCM approaches
EN
Objectives: The key test in Content-Based Medical Image Retrieval (CBMIR) frameworks for MRI (Magnetic Resonance Imaging) pictures is the semantic hole between the low-level visual data caught by the MRI machine and the elevated level data seen by the human evaluator. Methods: The conventional component extraction strategies centre just on low-level or significant level highlights and utilize some handmade highlights to diminish this hole. It is important to plan an element extraction structure to diminish this hole without utilizing handmade highlights by encoding/consolidating low-level and elevated level highlights. The Fleecy gathering is another packing technique, which is applied in plan depiction here and SVM (Support Vector Machine) is applied. Remembering the predefinition of bunching amount and enlistment cross-section is until now a significant theme, a new predefinition advance is extended in this paper, in like manner, and another CBMIR procedure is suggested and endorsed. It is essential to design a part extraction framework to diminish this opening without using painstakingly gathered features by encoding/joining low-level and critical level features. Results: SVM and FCM (Fuzzy C Means) are applied to the power structures. Consequently, the incorporate vector contains all the objectives of the image. Recuperation of the image relies upon the detachment among request and database pictures called closeness measure. Conclusions: Tests are performed on the 200 Image Database. Finally, exploratory results are evaluated by the audit and precision.
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