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This paper considers the problem of mining probabilistic frequent itemsets in the sliding window of an uncertain data stream. We design an effective in-memory index named PFIT to store the data synopsis, so the current probabilistic frequent itemsets can be output in real time. We also propose a depth-first algorithm, PFIMoS , to bottom-up build and maintain the PFIT dynamically. Because computing the probabilistic support is time consuming, we propose a method to estimate the range of probabilistic support by using the support and expected support, which can greatly reduce the runtime and memory usage. Nevertheless, massive probabilistic supports have to be computed when the minimum support is low over dense data, which may result in a drastic reduction of computing speed. We further address this problem with a heuristic rule-based algorithm, PFIMoS+ , in which an error parameter is introduced to decrease the probabilistic support computing count. Theoretical analysis and experimental studies demonstrate that our proposed algorithms can efficiently reduce computing time and memory, ensure fast and exact mining of probabilistic data streams, and markedly outperform the state-of-the-art algorithms TODIS-Stream (Sun et al., 2010) and FEMP (Akbarinia & Masseglia, 2013). [ABSTRACT FROM AUTHOR]

The outlier relies on its distinctive mechanism and valuable information to play an important role in expert and intelligent systems, and thus outlier detection has already been extensively applied in relevant fields including the fraud detection, medical diagnosis, public security, etc. The outlier detection methods of rough sets recently gain in-depth research, because they are data-driven and never require additional knowledge. However, classical rough set-based methods consider only categorical data; furthermore, neighborhood rough sets adhere to numeric and heterogeneous data, but their outlier detection is mainly restricted to numeric data now. According to the hybrid data-driving, this paper investigates outlier detection by the neighborhood information entropy and its developmental measures, and the applicable data sets widely concern categorical, numeric, and mixed data; as a result, the new method extends both the traditional distance-based and rough set-based methods to enrich outlier detection. Concretely, the neighborhood information system is first determined by the heterogeneous distance and self-adapting radius, the neighborhood information entropy is then defined to implement whole uncertainty measurement, three gradual information measures are further constructed to describe each single object, and finally the neighborhood entropy-based outlier factor (NEOF) is integratedly established to detect outliers; moreover, the NEOF-based outlier detection algorithm (called the NIEOD algorithm) is designed and applied. By virtue of UCI data experiments, the NIEOD algorithm is compared with six existing detection algorithms (including the NED, IE, SEQ, FindCBLOF, DIS, KNN algorithms), and the concrete results generally reflect the better effectiveness and adaptability of the new method. [ABSTRACT FROM AUTHOR]

In recent years, cyber-attacks against businesses and organizations have increased. Such attacks usually result in significant damage to the organization, such as the loss and/or leakage of sensitive and confidential information. Because email communication is an integral part of daily business operations, attackers frequently leverage email as an attack vector in order to initially penetrate the targeted organization. Email message allows the attacker to deliver dangerous content to the victim, such as malicious attachments or links to malicious websites. Existing email analysis solutions analyze only specific parts of the email using rule-based methods, while other important parts remain unanalyzed. Existing anti-virus engines primarily use signature-based detection methods, and therefore are insufficient for detecting new unknown malicious emails. Machine learning methods have been shown to be effective at detecting maliciousness in various domains and particularly in email. Previous works which used machine learning methods suggested sets of features which offer a limited perspective over the whole email message. In this paper, we propose a novel set of general descriptive features extracted from all email components (header, body, and attachments) for enhanced detection of malicious emails using machine learning methods. The proposed features are extracted just from the email itself; therefore, our features are independent, since the extraction process does not require an Internet connection or the use of external services or other tools, thereby meeting the needs of real-time detection systems. We conducted an extensive evaluation of our new novel features against sets of features suggested by previous academic work using a collection of 33,142 emails which contains 38.73% malicious and 61.27% benign emails. The results show that malicious emails can be detected effectively when using our novel features with machine learning algorithms. Moreover, our novel features enhance the detection of malicious emails when used in conjunction with features suggested by related work. The Random Forest classifier achieved the highest detection rates, with an AUC of 0.929, true positive rate (TPR) of 0.947, and false positive rate (FPR) of 0.03. We also present the IDR (integrated detection rate), a new measure which helps calibrate the threshold of a machine learning classifier in order to achieve the optimal TP and FP rates, which are the most important measures for a real-time and practical cyber-security application. [ABSTRACT FROM AUTHOR]

Voice activity detection (VAD) is an essential task in expert systems that rely on oral interfaces. The VAD module detects the presence of human speech and separates speech segments from silences and non-speech noises. The most popular current on-line VAD systems are based on adaptive parameters which seek to cope with varying channel and noise conditions. The main disadvantages of this approach are the need for some initialisation time to properly adjust the parameters to the incoming signal and uncertain performance in the case of poor estimation of the initial parameters. In this paper we propose a novel on-line VAD based only on previous training which does not introduce any delay. The technique is based on a strategy that we have called Multi-Normalisation Scoring (MNS). It consists of obtaining a vector of multiple observation likelihood scores from normalised mel-cepstral coefficients previously computed from different databases. A classifier is then used to label the incoming observation likelihood vector. Encouraging results have been obtained with a Multi-Layer Perceptron (MLP). This technique can generalise for unseen noise levels and types. A validation experiment with two current standard ITU-T VAD algorithms demonstrates the good performance of the method. Indeed, lower classification error rates are obtained for non-speech frames, while results for speech frames are similar. [ABSTRACT FROM AUTHOR]

The paper describes the development of a system for receiving questions from users and providing answers, which is a part of a larger knowledge-based (KB) system based on Node of Knowledge (NOK) conceptual framework for KB system development. A part of NOK conceptual framework is described, as well as a new method of text-expressed knowledge representation – formalized NOK (FNOK). Furthermore, the structure of system for user interaction and NOK based KB system named Question Answering NOK (QANOK) is presented. The paper answers the question whether it is possible to create a part of QANOK over FNOK formalized knowledge which would accept user questions using natural language and provide answers in natural language. Three algorithms were developed – an algorithm which translates text-expressed knowledge in natural language into FMTEK (Formalized Method for Text Expressed Knowledge) formalized notation, an algorithm which translates a question in natural language into qFMTEK (question FMTEK) formalized knowledge notation, and an algorithm which uses qFMTEK formalized question to find an answer within FMTEK formalized knowledge. Algorithms were tested against a predefined set of sentences and questions in English language. Limitations of developed algorithms are also presented, as well as further development of QANOK system. [ABSTRACT FROM AUTHOR]

Nesting Problems, which are important subjects in the cutting and packing field, involve convex and nonconvex polygons and are common in several industries. These irregular open dimensional problems have been studied for decades, particularly the variant with one open dimension. However, in real-world applications, situations that are better suited to a two open dimensional model may arise and, in this sense, the literature is very limited. We here propose new separation and compaction algorithms for two-open dimension nesting problem. The paper develops an adaptation of the no-fit polygon to consider the penetration depth of pieces. The approach is based on an iterative compaction scheme, in which the key step is an obstruction map-based separation algorithm. The algorithms proposed found optimal solutions for artificial instances with up to 28 items within a small runtime. The results of benchmark instances indicate that the new algorithm is competitive when compared with other literature algorithms. It improved 14 of 15 benchmark instances when considering literature approaches on two open dimensions. In addition, the new algorithm achieved better occupation for some open dimension instances than the state of the art. • 2 Open Dimension Problem. • Textile Industry Problem. • Separation and Compaction Algorithm. [ABSTRACT FROM AUTHOR]

In multi-view ensemble clustering, the correctly-partitioned data objects should be assigned with a higher weight, thereby helping to decrease the influence of incorrectly-partitioned data objects. Therefore, different data objects should be treated separately instead of being set the same view weight as traditional solutions. In this paper, a multi-view ensemble clustering approach is proposed using joint affinity matrix, which is generated by sample-level weight. Firstly, a new concept of core data objects is defined according to the influence index and Gaussian Mixed Model, and basic partitions and sample-level weights can be yielded for every view. Secondly, a joint affinity matrix, which maintains pairwise similarities of all data objects, is generated using the sample-level weights. Consequently, data objects can be effectively assigned to the correct partition. Thirdly, a multi-view ensemble clustering algorithm is proposed using the joint affinity matrix. In the end, experimental results on benchmark datasets validate the efficacy of the algorithm with state-of-the-art baselines. • Core data objects are redefined using Gaussian Mixed Model and nearest neighbors. • A single view clustering method without the specified number of clusters is proposed. • A new fusion mechanism is proposed to generate joint affinity matrix. • A multi-view ensemble clustering algorithm is proposed using joint affinity matrix. [ABSTRACT FROM AUTHOR]

Multimodal multiobjective optimization problems (MMOPs) possess multiple equivalent Pareto optimal sets (PSs) corresponding to the same Pareto front (PF). Numerous multimodal multiobjective evolutionary algorithms (MMEAs) have been developed to solve MMOPs. However, how to locate multiple high quality equivalent PSs and obtain a uniformly distributed PF simultaneously remains a challenging task. This paper explores a novel multimodal multiobjective differential evolution algorithm, termed MMO_CDE, for solving MMOPs. In MMO_CDE, a neighborhood-based dual mutation strategy is proposed by developing two novel mutation operators. The two novel mutation operators provide a better tradeoff between exploration and exploitation in locating multiple equivalent PSs. In addition, a clustering-based environmental selection mechanism is designed by integrating an affinity propagation method. The affinity propagation method improves the distribution of solutions in decision and objective spaces, and a harmonic averaged distance is adopted to promote the diversity of a population. The proposed MMO_CDE is compared against state-of-the-art MMEAs on a test suite of CEC 2019 benchmark functions and a map-based practical application. Empirical results validate the superiority of the proposed MMO_CDE regarding locating multiple equivalent PSs and obtaining a well-distributed PF. • Propose a clustering differential evolution with neighborhood-based dual mutation. • Develop a neighborhood-based dual mutation for the proposed algorithm. • Develop a clustering-based environmental selection for the proposed algorithm. [ABSTRACT FROM AUTHOR]

• A causal discovery algorithm based on rank correlation. • Apply Kendall correlation coefficient to causal discovery. • Lung nodule detection algorithm based on rank correlation. • Results demonstrate the feasibility of the proposed method. • The method can be applied to other medical tasks. Early diagnosis can significantly improve the survival rate of lung cancer patients. This study attempts to construct a causal structure network between the computational and semantic features of lung nodules through causal discovery algorithms, and to detect and prevent lung nodules based on this network. For complex and diverse lung nodule data sets, this paper proposes a new causal lung nodule detection algorithm Tau-CSFS in combination with rank correlation methods. The algorithm can effectively mine the causal relationship among lung cancer data that obey the non-linear non-Gaussian distribution, and the mixture of continuous and discrete variables, and has good predictive performance. We made three main contributions. First, we proved that the Kendall rank correlation coefficient that does not require data distribution can be used as a standard for independence test. Second, we applied Kendall rank correlation to Bayesian structure learning, and proposed a new causal discovery algorithm: Tau-CS algorithm based on hypothesis testing. The third contribution is to combine the Tau-CS algorithm with the feature selection method, and further propose the Tau-CSFS algorithm, which solves the problem of causality mining and diagnosis detection of lung nodule data. In the experiment, the Tau-CS algorithm is compared with the prior art on 7 Bayesian networks on the additive noise structure model, and it is proved that the algorithm has a better accuracy of causal structure learning. Finally, in the lung nodule detection stage, using the processed LIDC data set to perform two-classification and multi-classification experiments on seven semantic categories, the average accuracy of the Tau-CSFS algorithm reached 85.84% and 83.32%. The Tau-CSFS algorithm are better than comparable similar algorithms in the comprehensive performance index. The results show that the proposed algorithm has good detection performance and wide application prospects. [ABSTRACT FROM AUTHOR]

This aims to propose a collaborative filtering algorithm based on embedding representation and word embedding techniques, namely UI2vec. According to the joint feature extraction network designed in this paper, UI2vec embeds users and items on the potential space at the same time, and uses the item similarity between them to predict the user's content of interest. Then a generative model VUI2vec with more stable performance is proposed based on UI2vec, which maps users and items as independent Gaussian distributions and obtains the approximate posterior distribution of both by variational inference. The recommendation performance of UI2vec and VUI2vec is evaluated on TaFeng, Movielens, and Netflix datasets. The impact of important superparameters within the model on performance is investigated. The experimental results show that compared with the baseline model, the proposed methods performs consistently well. • UI2vec and VUI2vec as collaborative filtering-based recommendation systems. • It is based on embedding representation of users or items. • Performance is competitive with the state of the art on real-world datasets. • Results encourage integrating collaborative filtering with deep learning. [ABSTRACT FROM AUTHOR]

The balance between multiple objectives and various constraints is the key to solving constrained multi-objective optimization problems (CMOPs). When dealing with CMOPs with complex feasible regions, some evolutionary algorithms suffer from great challenges in converging to the constrained Pareto front (CPF) with well-distributed feasible solutions. To address this issue, this paper proposes a dual-population based bidirectional coevolution algorithm, called DBC-CMOEA, which aims to converge to the CPF using promising solutions explored from both feasible and infeasible regions. To do so, DBC-CMOEA maintains two populations and an archive, where the dual-population is complementary in the search process and the archive is used to retain promising feasible and infeasible solutions, thus facilitating information exchange between these two populations. For updating the archive, a nondominated sorting procedure and an angle-based selected scheme are conducted to store infeasible and feasible solutions, as they can help to maintain the diversity of the search and find more feasible regions. To evolve the CPF from the bidirectional side of the feasible region, a novel mating selection strategy is used to choose appropriate mating parents. In comparison with some related constraint multi-objective optimization algorithms on a number of benchmark problems, experimental results show that the proposed algorithm performs better than the state-of-the-art constrained multi-objective evolutionary optimizers. • A cooperative dual-population algorithm is proposed for solving CMOPs. • Constraints are handled in three different ways to explore the search space. • A brand-new selection strategy is applied to select the mating parents. • A novel archive update strategy is designed to retain the promising information. [ABSTRACT FROM AUTHOR]

• Present an anytime asymptotically-optimal motion planning algorithm. • Implement a heuristic cost evaluation to avoid unnecessary collision checks. • Analyze the swift convergence and the computational complexity for the algorithm. • The proposed algorithm is comprehensively evaluated by rigorous experiments. Practical applications favor anytime asymptotically-optimal algorithms that find a feasible solution and improve it toward the optimal solution within limited time. This paper proposed Informed Anytime Bi-directional Fast Marching Tree (IABFMT*), an anytime asymptotically-optimal sampling-based algorithm that combines the strength of BFMT* (bi-directional variant of FMT*) and IAFMT* (an anytime variant of FMT*). IABFMT* performs a bi-directional "lazy" search to efficiently find a feasible solution and quickly improve it towards optimal. In addition, we implemented a graph pruning method to simplify the planning problem and heuristic cost evaluation to reject samples, which avoided a lot of unnecessary computations and improved the convergence rate. Different simulations in OMPL have been carried out to demonstrate the superior efficiency of IABFMT* in comparison with other state-of-the-art algorithms in complex cluttered environments. [ABSTRACT FROM AUTHOR]

Software Defect Prediction (SDP) plays a vital role in the software development life cycle as it helps identify and fix software defects. However, predicting software defects with irrelevant features and overlapping classes is challenging and can lead to lengthy training and low model accuracy. To address these challenges, this research introduces a novel Depth Linear Discrimination-Oriented Feature Selection Method based on Adaptive Sine Cosine Algorithm, named Depth Adaptive Sine Cosine Feature Selection (DASC-FS). DASC-FS integrates the Adaptive Sine Cosine Algorithm (ASCA) as a search algorithm to determine the relevant features and adopts Depth Linear Discriminant Analysis (D-LDA) to identify the discriminative features that maximize class separation. The paper proposes ASCA which is a metaheuristic algorithm meticulously designed to enhance the search capabilities of the standard Sine Cosine Algorithm (SCA). Combining the simplicity of the SCA with the efficiency of multiple mutation operators inspired by Genetic Algorithms (GA), ASCA enhances the diversity of the solutions and imparts remarkable adaptability to various situations. Furthermore, this study introduces a novel linear discriminant method, called Depth Linear Discriminant Analysis (D-LDA) to enhance the robustness of the original LDA. D-LDA systematically integrates the matrix depth concept into LDA, offering a systematic approach to address the challenges associated with scatter matrix estimation. As matrix depth measures how central or deep a particular matrix is within a distribution with respect to different directions, it is an efficient tool for computing a robust scatter matrix estimator that can handle outliers and complex data structures. The experimental results showed that DASC-FS consistently obtains the highest accuracy compared to most existing methods by integrating ASCA and D-LDA, thereby considering both accuracy optimization and class separation. The results also show that the use of multiple mutation operators in ASCA improves the search process capabilities. The results also show that the capacity of D-LDA to reduce data dimensionality and increase class separation yields highly competitive results compared to other LDAs. Finally, features related to code size and complexity have emerged as key factors for SDP because they consistently rank as important features across different classifiers and datasets. DASC-FS offers a valuable solution in domain knowledge for enhancing predictive accuracy and understanding factors contributing to software defects through enhanced search capabilities, robust scatter matrix estimation, and the ability to reduce data dimensionality. [ABSTRACT FROM AUTHOR]

In most data dimensionality reduction tasks, feature selection (FS) is an essential preprocessing stage. The slime mould algorithm (SMA) is a novel metaheuristic optimization algorithm. This paper proposes a feature selection method for banknote dirtiness recognition based on mathematical functions driven slime mould algorithm. This method is applied to the feature selection of banknote dirtiness recognition, and the Lévy flight operator is used to replace the control parameter vc in SMA, and a series of mathematical functions are added to replace the control parameter vb in the slime mould algorithm to enhance the global search capability. Test results show that this method achieves the highest accuracy of 76.85 % in recognizing the banknote dirtiness. Additionally, by applying the same method to feature selection and recognition of dirtiness for the left middle white area images of banknotes, the highest accuracy reaches 74.99 %. This suggests that the left middle white area can essentially replace the whole banknote. To verify the performance of the proposed feature selection method, comparative tests with four other optimization algorithms are carried out, and the results demonstrate that three improvement strategies can effectively improve the performance of SMA while maintaining a balance between exploration and exploitation. Tests have revealed that these three algorithms have significant advantages over the past SMA in terms of recognition accuracy and convergence speed when it comes to identifying the dirtiness of banknotes. Therefore, this method is considered to be one of the most effective methods to solve the feature selection problem of banknote dirtiness. [ABSTRACT FROM AUTHOR]

The use of devices and technologies for the collection and processing of biometric data is continuously growing, in particular for the assessment of personal identity for accessing digital services, information systems, and control. A biometric system must be able to recognize and identify an individual by analyzing people's aspects that are unique, easily captured, permanent, and universal. The goal of this paper is to analyze the limits of biometry, in particular in the case of iris recognition. We take Coloboma, a rare eye pathology that leads to a deformation of the pupil, as a case study and we propose an extension of Daugman's algorithms able to perform biometric iris recognition. The algorithm extension impacts the segmentation phase of Daugman's algorithm, where the pupil is approximated by an ellipse instead of a circumference. Our extension obtains an improvement of 32% on the average error in the segmentation phase on pathological eyes. Utilizing this solution will allow individuals with Coloboma to avoid exclusion when accessing services through iris-based authentication. • We examine the boundaries of biometry in iris recognition. • We take Coloboma as a case study. • We propose an extension of Daugman's algorithm. • We achieve a 32% enhancement in the average error during the segmentation phase. [ABSTRACT FROM AUTHOR]

In this paper, we propose an advanced variational model for image segmentation and bias correction. In contrast to the majority of existing level set segmentation models that only consider illumination bias fields, we additionally consider the impact of image reflectance on segmentation accuracy. Our method is capable of effectively segmenting images with blurry edge structures affected by non-uniform illumination. In order to enhance segmentation efficiency, we directly segment the underlying structures of the images, construct spatial prior and apply adaptive regularization constraints on the structural component. Therefore, in the process of segmentation, the proposed algorithm can accurately identify object boundaries without being affected by the environment. Besides, the GL operator is applied to enhance the robustness of the model against noise. Furthermore, we use the alternating direction method of multipliers and the operator splitting algorithm for numerical solution. The experimental results obtained from various sorts of images illustrate that our model outperforms many leading-edge level set models with regard to robustness, corrected results and accuracy. • A novel image segmentation model based on image structural prior is introduced. • An adaptive regularization constraint for adaptive restoration of image intensity. • The model is robust to images with noise and intensity inhomogeneity. • The split operator and alternating minimization algorithm are combined. [ABSTRACT FROM AUTHOR]

We introduce a multidimensional multiblock clustering (MDMBC) algorithm in this paper. MDMBC can generate overlapping clusters with similar values along clusters of dimensions. The parsimonious binary vector representation of multidimensional clusters lends itself to the application of efficient meta-heuristic optimization algorithms. In this paper, a hill-climbing (HC) greedy search algorithm has been presented that can be extended by several stochastic and population-based meta-heuristic frameworks. The benefits of the algorithm are demonstrated in a bi-clustering benchmark problem and in the analysis of the Leiden higher education ranking system, which measures the scientific performance of 903 institutions along four dimensions of 20 indicators representing publication output and collaboration in different scientific fields and time periods. • Multiblock clustering algorithm generates overlapping clusters along clusters of dimensions. • Generalized parsimonious binary vector-based representation for higher-dimensions. • The proposed algorithms are demonstrated via an open multidimensional dataset. [ABSTRACT FROM AUTHOR]

Technology evolution and energy of particle impact both plays a major role in inducing multi-cycle transient fault (longer duration transient) in a device. However, designing an optimized multi-cycle fault tolerant system is non-trivial. This paper presents a novel design space exploration (DSE) approach for multi-cycle transient fault tolerant datapath based on user power-delay constraints during high level synthesis (HLS). To the best of the authors’ belief, this is the first work to solve this problem in the literature so far. More specifically, the current work in the literature so far utilizes ‘triple modular redundancy (TMR)’ to design a fault tolerant datapath, however, this paper proposes a ‘dual modular redundancy (DMR) design with equivalent circuit’ scheme to achieve the same. The novel equivalent circuit that works with DMR systems performs the function of extracting the correct output from the DMR design. Further, the proposed work is the first work in the literature that handles multi-cycle transient faults during design space exploration of fault tolerant datapath. Therefore, key contributions of this paper are as follows: (a) novel multi-cycle transient fault tolerant algorithm that has capability to isolate original and duplicate units in a DMR with respect to the transient fault; (b) novel DSE approach that combines our fault tolerant algorithm along with user specified conflicting power-performance constraint that guides this intractable search problem to reach an high quality fault tolerant solution without violating the power budget and delay requirement; (c) integrates a heuristic based on bacterial foraging optimization algorithm (BFOA) that performs adaptive searching. Finally, results indicated an average improvement in Quality of Results (QoR) of >24% and reduction in hardware usage of >57% of the final solution compared to similar approach. [ABSTRACT FROM AUTHOR]

Ensemble methods have been shown to be an effective tool for solving multi-label classification tasks. In the RAndom k -labELsets (RAKEL) algorithm, each member of the ensemble is associated with a small randomly-selected subset of k labels. Then, a single label classifier is trained according to each combination of elements in the subset. In this paper we adopt a similar approach, however, instead of randomly choosing subsets, we select the minimum required subsets of k labels that cover all labels and meet additional constraints such as coverage of inter-label correlations. Construction of the cover is achieved by formulating the subset selection as a minimum set covering problem (SCP) and solving it by using approximation algorithms. Every cover needs only to be prepared once by offline algorithms. Once prepared, a cover may be applied to the classification of any given multi-label dataset whose properties conform with those of the cover. The contribution of this paper is two-fold. First, we introduce SCP as a general framework for constructing label covers while allowing the user to incorporate cover construction constraints. We demonstrate the effectiveness of this framework by proposing two construction constraints whose enforcement produces covers that improve the prediction performance of random selection by achieving better coverage of labels and inter-label correlations. Second, we provide theoretical bounds that quantify the probabilities of random selection to produce covers that meet the proposed construction criteria. The experimental results indicate that the proposed methods improve multi-label classification accuracy and stability compared to the RAKEL algorithm and to other state-of-the-art algorithms. [ABSTRACT FROM AUTHOR]

In this paper, we present a multibiometric system based on two different biometric modalities, palmprint and fingerprint. The proposed system is based on a score fusion which can effectively combine the discriminative power of multiple biometric traits. We propose a combined fingerprint image enhancement, which achieves satisfactory results. We also apply two different indexing algorithms on fingerprints and three different indexing algorithms on palmprints. Existing multibiometric systems are not sufficiently fast for practical applications. Indexing and retrieval mechanisms can effectively narrow down the search space in large databases. We propose a fingerprint indexing based on ellipse properties, which reduces false correspondences. The proposal uses a k-means clustering algorithm to index and retrieve fingerprints and palmprints. Furthermore, we combine some minutia cylinder-code (MCC)-based algorithms and improve the MCC-based indexing algorithms. Empirical experiments on some of datasets of the national institute of standards and technology (NIST), fingerprint verification competition (FVC), and THUPALMLAB databases show that the proposed algorithm considerably narrows down the search space in fingerprint and palmprint databases and increase the recognition performance. [ABSTRACT FROM AUTHOR]

Recommender systems use algorithms to provide users with product or service recommendations. Recently, these systems have been using machine learning algorithms from the field of artificial intelligence. However, choosing a suitable machine learning algorithm for a recommender system is difficult because of the number of algorithms described in the literature. Researchers and practitioners developing recommender systems are left with little information about the current approaches in algorithm usage. Moreover, the development of recommender systems using machine learning algorithms often faces problems and raises questions that must be resolved. This paper presents a systematic review of the literature that analyzes the use of machine learning algorithms in recommender systems and identifies new research opportunities. The goals of this study are to (i) identify trends in the use or research of machine learning algorithms in recommender systems; (ii) identify open questions in the use or research of machine learning algorithms; and (iii) assist new researchers to position new research activity in this domain appropriately. The results of this study identify existing classes of recommender systems, characterize adopted machine learning approaches, discuss the use of big data technologies, identify types of machine learning algorithms and their application domains, and analyzes both main and alternative performance metrics. [ABSTRACT FROM AUTHOR]

Expert and intelligent systems understand the underlying information behind the data by relying on a wide range of machine learning techniques. The interpretation of machine learning models is often the key to success in research areas such as business, finance, medical and health science, and bioinformatics; such research areas demand human understanding of the obtained model. The logistic model tree (LMT) algorithm is a popular classification method that combines a decision tree and logistic regression models. The combination of two complementary algorithms produces an accurate and interpretable classifier by combining the advantages of both logistic regression and tree induction. However, LMT has the disadvantage of high computational cost, which makes the algorithm undesirable in practice. In this paper, we propose an efficient method to learn the logistic regression models in the tree. We employ least angle regression to update the regression model in LogitBoost so that the algorithm efficiently learns sparse logistic regression models composed of relevant input variables. We compare the performance of our proposed method with the original LMT algorithm using 14 benchmark datasets and show that the training time dramatically decreases while the accuracy is preserved. Our proposed algorithm is not only accurate and intuitively interpretable but also computationally efficient. It helps users in making the best possible use of the data that are included in expert and intelligent systems. [ABSTRACT FROM AUTHOR]

Frequent pattern mining is considered a key task to discover useful information. Despite the quality of solutions given by frequent pattern mining algorithms, most of them face the challenge of how to reduce the number of frequent patterns without information loss. Frequent itemset mining addresses this problem by discovering a reduced set of frequent itemsets, named closed frequent itemsets , from which the entire frequent pattern set can be recovered. However, for frequent similar pattern mining , where the number of patterns is even larger than for Frequent itemset mining, this problem has not been addressed yet. In this paper, we introduce the concept of closed frequent similar pattern mining to discover a reduced set of frequent similar patterns without information loss. Additionally, a novel closed frequent similar pattern mining algorithm, named CFSP-Miner , is proposed. The algorithm discovers frequent patterns by traversing a tree that contains all the closed frequent similar patterns. To do this efficiently, several lemmas to prune the search space are introduced and proven. The results show that CFSP-Miner is more efficient than the state-of-the-art frequent similar pattern mining algorithms, except in cases where the number of frequent similar patterns and closed frequent similar patterns are almost equal. However, CFSP-Miner is able to find the closed similar patterns, yielding a reduced size of the discovered frequent similar pattern set without information loss. Also, CFSP-Miner shows good scalability while maintaining an acceptable runtime performance. [ABSTRACT FROM AUTHOR]

Due to the rapid extension of social networks in recent years, a new potential has emerged for global spreading of messages and effective broadcasting of news. Identification of influential nodes within a network is now seen as a key factor for bringing this potential into action. k -shell is a measure for detection of node influence, and has already been used in some successful algorithms in this field. However, k-shell does not provide enough information about the topological positions of the nodes, and the present paper seeks to present a special hierarchical measure for dealing with this issue. Along with introduction of the above measure, it is shown that it can be used for detecting and ranking node influence. The experiments done on real-world and artificial networks demonstrate that the proposed approach can rank the influence of nodes more accurately than other approaches. [ABSTRACT FROM AUTHOR]

In recent years, credit scoring has become an efficient tool that allows financial institutions to differentiate their potential default borrowers. Accordingly, researchers have developed a myriad of approaches, including statistical and artificial intelligence techniques, to fulfill the task of credit scoring. Recent studies have shown that ensemble methods, which combine multiple algorithms that process different hypotheses to form a new hypothesis, generally outperform the other credit scoring approaches. In this paper, we propose a novel heterogeneous ensemble credit model that integrates the bagging algorithm with the stacking method. The proposed model differs from the extant ensemble credit models in three aspects, namely, pool generation, selection of base learners, and trainable fuser. Four popular evaluation metrics, including accuracy, area under the curve (AUC), AUC-H measure, and Brier score, are employed to measure the performance of alternative models. To confirm the efficiency of the proposed bstacking approach, a wide range of models, including individual classifiers, homogeneous ensemble model, and heterogeneous ensemble model, are introduced as benchmarks. We also provided a discussion on the accurate yet complex credit scoring model (e.g., bstacking) from a regulatory perspective. [ABSTRACT FROM AUTHOR]

Dimensionality reduction becomes a significant problem due to the proliferation of high dimensional data. Sparse preserving projection (SPP) obtains the intrinsic geometric structure of the data, which contains natural discriminating information, and avoids the selection of parameters as well. However, SPP neglects the global structures since it computes the sparse representation of each data individually. Low rank representation (LRR), another commonly used dimensionality reduction method, finds the lowest rank representation of all data jointly, and is capable of capturing the global structures of data. Therefore in this paper, we propose a method, global and intrinsic geometric structure embedding for unsupervised feature selection (GGEFS), by constructing a low-rank-sparse graph. Our GGEFS method contains the loss of information, the preservation of structural information and the sparse regularization of projection matrix, on which we impose l 2,1/2 -matrix norm to select sparser and discriminative features. An effective iterative algorithm based on Lagrange Multiplier method is described to solve GGEFS. Extensive experimental results demonstrate that the proposed algorithm outperform several state-of-the-art unsupervised feature selection methods. [ABSTRACT FROM AUTHOR]

Due to the continuous growth of social networks the textual information available has increased exponentially. Data warehouses (DW) and online analytical processing (OLAP) are some of the established technologies to process and analyze structured data. However, one of their main limitations is the lack of automatic processing and analysis of unstructured data (specifically, textual data), and its integration with structured data. This paper proposes the creation, integration and implementation of a new dimension called Contextual Dimension from texts obtained from social networks into a multidimensional model. Such a dimension is automatically created after applying hierarchical clustering algorithms and is fully independent from the language of the texts. This dimension allows the inclusion of multidimensional analysis of texts using contexts and topics integrated with conventional dimensions into business decisions. The experiments were carried out by means of a freeware OLAP system (Wonder 3.0) using real data from social networks. [ABSTRACT FROM AUTHOR]

Events prediction in a sequence of events is a challenging task that can be approached with data mining. In this paper, we focus on the specific case of early prediction of distant events. We aim at mining episode rules with a consequent temporally distant from the antecedent and an antecedent as small as possible both in number of events and in occurrence duration. We refer to these rules as essential rules . To reach this goal, we propose an original algorithm, DEER : Distant and Essential Episode Rules. This algorithm differs from traditional algorithms in three points. First, it determines the consequent of episode rules at an early stage in the mining process, which allows to mine rules with an antecedent as small as possible. Second, it applies a minimal gap constraint between the antecedent and the consequent to guarantee a suitable distance between both elements. Third, the stop criterion used considers both the support and the confidence of the rules, at the opposite of traditional algorithms that use only the support. Experiments on both synthetic and real datasets show that DEER runs faster than several algorithms of the state-of-the-art and has also good scalability on large datasets. Furthermore, by studying in details the episode rules mined from a real dataset of blog messages, we demonstrate not only the efficiency of our algorithm for mining interesting essential rules with a distant consequent, but also that these rules can be used to accurately predict distant events. [ABSTRACT FROM AUTHOR]

This paper presents new feature selection algorithms for aggregate data analysis. Data aggregation is commonly used when it is not appropriate to model the relationship between a response and explanatory variables at an individual-level. We investigate substantial challenges in analysis for aggregate data. Then, we propose a groupwise feature selection method that addresses (i) the change in dataset depending on the selection of predictor variables, (ii) the presence of potential missing responses, and (iii) the suitability of model selection criteria when comparing models using different datasets. In application to real auto insurance data, we find a set of important predictors to classify the policyholders into some homogeneous risk groups. Our results clearly demonstrate the potential of the proposed feature selection method for aggregate data analysis in terms of flexibility and computational complexity. We expect that the proposed algorithms would be further applied into a wide range of decision-making tasks using aggregate data as they are applicable to any type of data. [ABSTRACT FROM AUTHOR]

Application architectures in the cloud employ elastic components, and achieve lower operating costs without sacrificing quality. Software architects strive to provide efficient services by deciding on software topology: a set of structural architectural decisions. For a given application, there can be numerous software topology alternatives creating the need for automated optimization methods. Current optimization approaches rely on experts providing application performance models built upfront, based on their experience and the requirements provided. While such techniques are effective and valuable, they require additional maintenance effort as the software evolves. This paper introduces ElaClo, a framework for optimizing application topologies in a cloud environment. ElaClo’s main contribution is in providing optimization in the software assembly phase from automatically extracted application models. ElaClo provides workload generation, monitoring, topology management, elasticity mechanisms, and algorithms to support the optimization process. We have implemented ElaClo as an expert tool and evaluated it on a real-life cloud application from the retailing business domain. ElaClo was used to select optimal topologies with regards to service response time objectives and infrastructure costs. The efficiency of the optimization process and the quality of optimization results were validated quantitatively on a set of optimization runs. Results demonstrate the effectiveness of the suggested framework in yielding optimal topologies. [ABSTRACT FROM AUTHOR]

By present, many models of bankruptcy forecasting have been developed, but this area remains a field of research activity; little is known about the practical application of existing models. In our opinion, this is because the use of existing models is limited by the conditions in which they are developed. Another question concerns the factors that can be significant for forecasting. Many authors suggest that indicators of the external environment, corporate governance as well as firm size contain important information; on the other hand, the large number of factors does not necessary increase predictive ability of a model. In this paper, we suggest the genetic algorithm based two-step classification method (TSCM) that allows both selecting the relevant factors and adapting the model itself to application. Classifiers of various models are trained at the first step and combined into the voting ensemble at the second step. The combination of random sampling and feature selection techniques were used to ensure the necessary diversity level of classifiers at the first step. The genetic algorithms are applied at the step of features selection and then at the step of weights determination in ensemble. The characteristics of the proposed method have been tested on the balanced set of data. It included 912 observations of Russian companies (456 bankrupts and 456 successful) and 55 features (financial ratios and macro/micro business environment factors). The proposed method has shown the best accuracy (0.934) value among tested models. It has also shown the most balanced precision-recall ratio. It found bankrupts (recall = 0.953) and not bankrupts (precision = 0.910) rather accurately than other tested models. The ability of method to select the task-relevant features has been also tested. Excluding the features that are significant for less than 50% of the classifiers in the ensemble improved the all performance metrics (accuracy = 0.951, precision = 0.932, recall = 0.965). So, the proposed method allows to improve the advantages and alleviate the weaknesses inherent in ordinary classifiers, enabling the business decisions support with a higher reliability. [ABSTRACT FROM AUTHOR]

Feature selection, both for supervised as well as for unsupervised classification is a relevant problem pursued by researchers for decades. There are multiple benchmark algorithms based on filter, wrapper and hybrid methods. These algorithms adopt different techniques which vary from traditional search-based techniques to more advanced nature inspired algorithm based techniques. In this paper, a hybrid feature selection algorithm using graph-based technique has been proposed. The proposed algorithm has used the concept of Feature Association Map (FAM) as an underlying foundation. It has used graph-theoretic principles of minimal vertex cover and maximal independent set to derive feature subset. This algorithm applies to both supervised and unsupervised classification. The performance of the proposed algorithm has been compared with several benchmark supervised and unsupervised feature selection algorithms and found to be better than them. Also, the proposed algorithm is less computationally expensive and hence has taken less execution time for the publicly available datasets used in the experiments, which include high-dimensional datasets. [ABSTRACT FROM AUTHOR]

This paper presents an improved version of the well-established k nearest neighbor ( k -NN) and fuzzy NN (FNN), termed the multi-objective genetic-algorithm-modified FNN (MOGA-MFNN). The MFNN design problem is converted into a multi-modal objective maximization problem constrained by four objective functions. Thereafter, the associated parameter set of the MFNN and the feature attributes can be determined optimally and automatically via the non-dominated sorting genetic algorithm II. We introduce two new objective functions termed the Margin-I and Margin-II, which are used to improve the generalization capability of the MFNN for the unknown data, along with two existing performance functions: the geometric mean and the area under the receiver-operated characteristic curve for the training accuracy. Moreover, we proposed a novel data-dependent weight-assignment technique for local class membership functions of the MFNN. The technique enables the MFNN to determine its local neighbors adaptively through the MOGA algorithm. To expedite the classification, the MOGA-MFNN is implemented on a graphical processing unit (GPU), which significantly increases the computation speed. Furthermore, the local class-membership function of the MFNN can be computed in advance, rather than delaying it to the classification stage. This again can improve the classification speed. The MOGA-MFNN is evaluated on 20 datasets obtained from the repository of the University of California, Irvine (UCI). The experiments with rigorous statistical significance tests demonstrate that the proposed method performs competitively with the existing methods. [ABSTRACT FROM AUTHOR]

Despite many years of research, correct and reliable segmentation of touching characters is still a hard task to solve. In the recent years, many methods and algorithms have been proposed; nevertheless the problem is still open. In this paper, we propose a novel method based on fuzzy logic that combines three different techniques to segment touching characters. These techniques have already been used in other studies but they have never been used all together. We propose a 3–input/1–output fuzzy inference system with fuzzy rules that are specifically optimized to segment touching Latin characters. The method is applicable to both printed and handwritten characters. We discuss the performances of our method by comparing it with state of the art. Results show that our method provide a better accuracy to segment characters even with noisy touching characters. [ABSTRACT FROM AUTHOR]

The accurate detection of web robot sessions from a web server log is essential to take accurate traffic-level measurements and to protect the performance and privacy of information on a Web server. Moreover, the irrecoverable risks of visits from malicious robots that intentionally try to evade web server intrusion detection systems, covering-up their visits with fabricated fields in their http request packets, cannot be ignored. To separate both types of robots from humans in practice, analysts turn to heuristic methods or state-of-the-art soft computing approaches that have only been tuned to the specification of a kind of web server. Noting that the landscape of web robot agents is ever changing, and that behavioral patterns and characteristics vary across different web servers, both options are lacking. To overcome this challenge, this paper presents SMART, a soft computing system that simultaneously detects benign and malicious types of robot agents from web server logs and can automatically adapt to the session characteristics of a web server. The results of experiments over some access log file servers, each servicing different domains of the web, demonstrate outperformance of the proposed method on state-of-the-art ones for benign and malicious robot detection. [ABSTRACT FROM AUTHOR]

In this paper, a novel two-archive Multi-Objective Grey Wolf Optimizer (2ArchMGWO) is proposed for solving Multi-Objective Optimal Reactive Power Dispatch (MORPD) problems. The optimizer has been improved from its original Multi-Objective Grey Wolf Optimizer (MGWO) by modifying the reproduction operator and adding the 2-archive concept to the algorithm. It is then implemented on solving MORPD with objective functions being active power loss minimization and voltage profile improvement (voltage deviation minimization). The generator bus voltages, tap setting transformers and shunt reactive power sources or flexible alternating current transmission systems are set as design variables. The proposed algorithm along with other existing multiobjective optimizers are applied to solve three test problems with the standard IEEE 30-bus, IEEE 57-bus, and the IEEE 118-bus power systems. The optimum results obtained from the various optimizers performance are compared based on the hypervolume indicator and they reveal that 2ArchMGWO is clearly superior to the others. [ABSTRACT FROM AUTHOR]

Learning from imbalanced datasets is challenging for standard algorithms, as they are designed to work with balanced class distributions. Although there are different strategies to tackle this problem, methods that address the problem through the generation of artificial data constitute a more general approach compared to algorithmic modifications. Specifically, they generate artificial data that can be used by any algorithm, not constraining the options of the user. In this paper, we present a new oversampling method, Self-Organizing Map-based Oversampling (SOMO), which through the application of a Self-Organizing Map produces a two dimensional representation of the input space, allowing for an effective generation of artificial data points. SOMO comprises three major stages: Initially a Self-Organizing Map produces a two-dimensional representation of the original, usually high-dimensional, space. Next it generates within-cluster synthetic samples and finally it generates between cluster synthetic samples. Additionally we present empirical results that show the improvement in the performance of algorithms, when artificial data generated by SOMO are used, and also show that our method outperforms various oversampling methods. [ABSTRACT FROM AUTHOR]

Multi-class sentiment classification has extensive application backgrounds, whereas studies on this issue are still relatively scarce. In this paper, a framework for multi-class sentiment classification is proposed, which includes two parts: 1) selecting important features of texts using the feature selection algorithm, and 2) training multi-class sentiment classifier using the machine learning algorithm. Then, experiments are conducted for comparing the performances of four popular feature selection algorithms (document frequency, CHI statistics, information gain and gain ratio) and five popular machine learning algorithms (decision tree, naïve Bayes, support vector machine, radial basis function neural network and K-nearest neighbor) in multi-class sentiment classification. The experiments are conducted on three public datasets which include twelve data subsets, and 10-fold cross validation is used to obtain the classification accuracy concerning each combination of feature selection algorithm, machine learning algorithm, feature set size and data subset. Based on the obtained 3600 classification accuracies (4 feature selection algorithms × 5 machine learning algorithms × 15 feature set sizes × 12 data subsets), the average classification accuracy of each algorithm is calculated, and the Wilcoxon test is used to verify the existence of significant difference between different algorithms in multi-class sentiment classification. The results show that, in terms of classification accuracy, gain ratio performs best among the four feature selection algorithms and support vector machine performs best among the five machine learning algorithms. In terms of execution time, the similar comparisons are also conducted. The obtained results would be valuable for further improving the existing multi-class sentiment classifiers and developing new multi-class sentiment classifiers. [ABSTRACT FROM AUTHOR]

To solve, manage and analyze biological problems using computer technology is called bioinformatics. With the emergent evolution in computing era, the volume of biological data has increased significantly. These large amounts of data have increased the need to analyze it in reasonable space and time. DNA sequences contain basic information of species, and pattern matching between different species is an important and challenging issue to cope with. There exist generalized string matching and some specialized DNA pattern matching algorithms in the literature. There is still need to develop fast and space efficient pattern matching algorithms that consider new hardware development. In this paper, we present a novel DNA sequences pattern matching algorithm called EPMA. The proposed algorithm utilizes fixed length 2-bits binary encoding, segmentation and multi-threading. The idea is to find the pattern with multiple searcher agents concurrently. The proposed algorithm is validated with comparative experimental results. The results show that the new algorithm is a good candidate for DNA sequence pattern matching applications. The algorithm effectively utilizes modern hardware and will help researchers in the sequence alignment, short read error correction, phylogenetic inference etc. Furthermore, the proposed method can be extended to generalized string matching and their applications. [ABSTRACT FROM AUTHOR]

Recently, researchers discovered that the major problems of mining event logs is to discover a simple, sound and complete process model. But since the mining techniques can only reproduce the behaviour recorded in the log, the fitness of the reproduced model is a function of the event log completeness. In this paper, a Fuzzy-Genetic Mining model based on Bayesian Scoring Functions (FGM-BSF) which we called probabilistic approach was developed to tackle problems which emanated from the incomplete event logs. The main motivation of using genetic mining for the process discovery is to benefit from the global search performed by the algorithm. The incompleteness in processes deals with uncertainty and is tackled by using the probabilistic nature of the scoring functions in Bayesian network based on a fuzzy logic value prediction. The global search performed by the genetic approach is panacea to dealing with the population that has both good and bad individuals. Hence, the proposed approach helps to enhance a robust fitness function for the genetic algorithm through highlift traces representing only good individuals not detected by mining model without an intelligent system . The implementation of our approach was carried out on java platform with MySQL for event log parsing and preprocessing while the actual discovery was done in ProM. The results showed that the proposed approach achieved 0.98% fitness when compared with existing schemes. [ABSTRACT FROM AUTHOR]

This study investigates stock market indices prediction that is an interesting and important research in the areas of investment and applications, as it can get more profits and returns at lower risk rate with effective exchange strategies. To realize accurate prediction, various methods have been tried, among which the machine learning methods have drawn attention and been developed. In this paper, we propose a basic hybridized framework of the feature weighted support vector machine as well as feature weighted K -nearest neighbor to effectively predict stock market indices. We first establish a detailed theory of feature weighted SVM for the data classification assigning different weights for different features with respect to the classification importance. Then, to get the weights, we estimate the importance of each feature by computing the information gain. Lastly, we use feature weighted K-nearest neighbor to predict future stock market indices by computing k weighted nearest neighbors from the historical dataset. Experiment results on two well known Chinese stock market indices like Shanghai and Shenzhen stock exchange indices are finally presented to test the performance of our established model. With our proposed model, it can achieve a better prediction capability to Shanghai Stock Exchange Composite Index and Shenzhen Stock Exchange Component Index in the short, medium and long term respectively. The proposed algorithm can also be adapted to other stock market indices prediction. [ABSTRACT FROM AUTHOR]

Algorithms for retinal vessel segmentation are powerful tools in automatic tracking systems for early detection of ophthalmological and cardiovascular diseases, and for biometric identification. In order to create more robust and reliable systems, the algorithms need to be accurately evaluated to certify their ability to emulate specific human expertise. The main contribution of this paper is an unsupervised method to detect blood vessels in fundus images using a coarse-to-fine approach. Our methodology combines Gaussian smoothing, a morphological top-hat operator, and vessel contrast enhancement for background homogenization and noise reduction. Here, statistics of spatial dependency and probability are used to coarsely approximate the vessel map with an adaptive local thresholding scheme. The coarse segmentation is then refined through curvature analysis and morphological reconstruction to reduce pixel mislabeling and better estimate the retinal vessel tree. The method was evaluated in terms of its sensitivity, specificity and balanced accuracy. Extensive experiments have been conducted on DRIVE and STARE public retinal images databases. Comparisons with state-of-the-art methods revealed that our method outperformed most recent methods in terms of sensitivity and balanced accuracy with an average of 0.7819 and 0.8702, respectively. Also, the proposed method outperformed state-of-the-art methods when evaluating only pathological images that is a more challenging task. The method achieved for this set of images an average of 0.7842 and 0.8662 for sensitivity and balanced accuracy, respectively. Visual inspection also revealed that the proposed approach effectively addressed main image distortions by reducing mislabeling of central vessel reflex regions and false-positive detection of pathological patterns. These improvements indicate the ability of the method to accurately approximate the vessel tree with reduced visual interference of pathological patterns and vessel-like structures. Therefore, our method has the potential for supporting expert systems in screening, diagnosis and treatment of ophthalmological diseases, and furthermore for personal recognition based on retinal profile matching. [ABSTRACT FROM AUTHOR]

Large graphs are scale free and ubiquitous having irregular relationships. Clustering is used to find existent similar patterns in graphs and thus help in getting useful insights. In real-world, nodes may belong to more than one cluster thus, it is essential to analyze fuzzy cluster membership of nodes. Traditional centralized fuzzy clustering algorithms incur high communication cost and produce poor quality of clusters when used for large graphs. Thus, scalable solutions are obligatory to handle huge amount of data in less computational time with minimum disk access. In this paper, we proposed a parallel fuzzy clustering algorithm named ‘PGFC’ for handling scalable graph data. It will be advantageous from the viewpoint of expert systems to develop a clustering algorithm that can assure scalability along with better quality of clusters for handling large graphs.The algorithm is parallelized using bulk synchronous parallel (BSP) based Pregel model. The cluster centers are initialized using degree centrality measure, resulting in lesser number of iterations. The performance of PGFC is compared with other state of art clustering algorithms using synthetic graphs and real world networks. The experimental results reveal that the proposed PGFC scales up linearly to handle large graphs and produces better quality of clusters when compared to other graph clustering counterparts. [ABSTRACT FROM AUTHOR]

• A trinocular vision system is set up for orchard obstacle avoidance. • Grayscale morphology filtering is used for trunk regions enhancement. • Optical flow method is used for trunk regions prediction. • Coupling geometric constraint and VFF method for obstacle avoidance. Nowadays the use of visual navigation in orchard is rapidly growing, while current research mainly focuses on orchard row detection or obstacle detection separately. The economic, fast and reliable navigation vision system that completing orchard row following and obstacle avoidance simultaneously and the obstacle avoidance algorithm for vision system without complex multiple navigation systems combining are needed further research. In this paper, a trinocular vision system for orchard vehicle is set up and the obstacle avoidance algorithm based on coupling of geometric constraint and virtual force field is designed for its vision system. First of all, based on analyzing the different vision system characteristics and the detection demand of orchard obstacle avoidance the trinocular vision system for orchard vehicle is set up based on a wide-angle camera and binocular stereo vision system. Then, the image processing algorithm of orchard row and obstacle detection is designed. For orchard row detection, the trunk regions enhancement algorithm is designed based on grayscale morphology filtering the trunk regions prediction algorithm is designed based on optical flow method to improve the trunk regions detection speed and accuracy. For obstacle detection, the background equalization algorithm based on H-channel image characteristics and the interference weaken algorithm with G-channel image characteristics are designed. Based on the row and obstacle detection results the algorithm for obstacle avoidance in orchard based on coupling of geometric constraint and virtual force field is designed. In the obstacle avoidance process, the virtual force field method is used as the mainly control of the vehicle obstacle avoidance process, and the geometric constraint between visual model of trinocular vision system and obstacle position is coupling with it to fulfill the avoidance demand of the obstacle with special shape and other condition that influence the virtual force field calculation. The experimental results show that the trinocular vision system for orchard vehicle built in this paper has strong adaptability to the actual environment which is accurate and stable for orchard row detection and obstacle detection simultaneously. The average deviation is 4.76 cm and 7.05 cm at 0.5 m/s and 1.0 m/s respectively, the average deviation of obstacle distance detection in the Z-axis direction is 3.18 cm, and in the X-axis direction is 0.45 cm. And the obstacle avoidance algorithm designed in this paper is effective in the orchard which can meet the actual production requirements. The research results will lay a foundation for the development of intelligent equipment and unmanned management in orchard. [ABSTRACT FROM AUTHOR]

• Time burst characteristic is studied by 3 aspects in fake review identification. • A suspicion degree method of fake reviews is proposed from (1) by LOF algorithm. • A fake review identification framework is given including the suspicion degree. • The case study shows that the proposed method outperforms the existed methods. With the rapid development of e-commerce, online reviews have played an increasingly important role in consumers' shopping intentions and behaviors. Therefore, how to effectively identify fake reviews has become one of the important issues that need to be resolved. Since the existing methods do not fully consider the time burst characteristics of reviews, this paper proposes a suspicion degree determining method based on the three-dimensional time series. Besides, combining the suspicion degree feature, review text features, and reviewer's behavior features together, this paper proposes a more comprehensive fake review identification framework. The yelp and amazon public data sets are carried out to verify the effectiveness of the proposed method, and the experimental results show that the proposed method outperforms the most advanced methods. [ABSTRACT FROM AUTHOR]

This paper aims at presenting a compilation of state-of art references in which dynamic programming (DP) and its variants have been applied as a solution methods for the deterministic machine scheduling problems. Overall, 183 articles have been gathered and their segmentation was carried out according to the machine environment that characterized the problems addressed by the authors and ultimately, the objective functions that were intended to be optimized. Additionally, we standardized the information provided by each article by presenting the problems discussed by the authors, comparisons between previous works on the same problem (if it was deemed necessary), the algorithms' complexities and an extension of methods to computational experiments (in case they have been stated). Finally, at the end of each section we furnish a discussion on the main contributions of DP to the each environment and also suggest some further applications of DP to machine scheduling problems, thus showing the potential resources that can be derived from the method in terms of theoretical/practical approaches. • Review of 175 papers associating dynamic programming and machine scheduling. • Papers are segmented according to the environment and objective function. • Tables are furnished so as to direct the reader to the intended literature. • Qualitative analysis regarding journals and dynamic programming is presented. • Suggestions for covering some gaps in the literature are provided. [ABSTRACT FROM AUTHOR]

• Case study on the transit network design and frequency setting problem. • Alternative lines plans are generated using a bi-objective memetic algorithm. • Realistic characteristics are incorporated in the model. • A large instance is proposed using real data, explaining the generation process. • The results are compared with the current situation using newly proposed metrics. This paper presents an approach to design better line plans for realistic cases. The planning problem is modelled as a realistic instance of the Transit Network Design and Frequency Setting Problem (TNDFSP). It incorporates additional assumptions taken from practice such as discrete frequencies, a subset of allowed terminal nodes and circular lines. A bi-objective memetic algorithm minimizes the average travel time (ATT) of the passengers and the fleet size. The method to generate the TNDFSP instance from real data is described in detail. Moreover, a new metric is proposed to compare different transit networks. In order to illustrate the approach, it is applied to the area of Utrecht, The Netherlands. The results show that the current network is modelled accurately and that the algorithm successfully generates alternative bus line plans within reasonable CPU time. It returns a subset of non-dominated solutions from which a compromise solution can be selected for practice. There are solutions with the same fleet size as the current solution, but a 6% lower ATT, or solutions with the same ATT, but a fleet size which is 19% smaller. Compared to the current network, the algorithm finds that it is convenient to substantially reduce the number of lines and to leave a small portion of demand unsatisfied. This paper also presents extensive experiments to test the impact of different assumptions about demand, bus capacity and minimum frequency. [ABSTRACT FROM AUTHOR]

• Proposing two new models for humanitarian logistic for pre and post disaster. • Considering outsourcing, QFC, and uncertain demands. • Using AEC, NSGA-II and NRGA for small and large-sized problems. • Need to pay attention to demand, internal supplier capacity, and the QFC parameters. • Better results of NRGA than NSGA-II in terms of most indicators of this paper. The extant study aimed to create a kind of coordination in the humanitarian chain by using a quantity flexibility (QF) contract. The QF contract considers a kind of coordination between a relief organization and a producer for inventory management determining order volumes. Due to insufficiency of amenities or time limits during the crisis, an internal producer can outsource a part of its duties to an external producer to produce items and accelerate the relief process. Hence, this study proposed a completely novel bi-objective mathematical model to coordinate relief items' supply and distribution by using QF contracts and buying in the spot market under demand uncertainty conditions to reduce costs and accelerate relief services. The augmented epsilon constraint method was used to solve the small scales of this model and NSGA-II and NRGA algorithms were employed to solve large scales. The results indicated the powerful performance of NRGA in terms of most evaluation indicators. [ABSTRACT FROM AUTHOR]

Smart contracts struggle with the major limitation of operating on data that is solely residing on the blockchain network. The need of recruiting third parties, known as oracles, to assist smart contracts has been recognized with the emergence of blockchain technology. Oracles could be deviant and commit ill-intentioned behaviors, or be selfish and hide their actual available resources to gain optimal profit. Current research proposals employ oracles as trusted entities with no robust assessment mechanism, which entails a risk of turning them into centralized points of failure. The need for an effective method to select the most economical and rewarding oracles that are self-interested and act independently is somehow neglected. Thus, this paper proposes a Bayesian Bandit Learning Oracles Reliability (BLOR) mechanism to identify trustless and cost-efficient oracles. Within BLOR, we learn the behavior of oracles by formulating a Bayesian cost-dependent reputation model and utilize reinforcement learning (knowledge gradient algorithm) to guide the learning process. BLOR enables all the blockchain validators to verify the obtained results while running the algorithm at the same time by dealing with the randomness issue within the limited blockchain structure. We implement and experiment with BLOR using Python and the Solidity language on Ethereum. BLOR is benchmarked against several models where it proved to be highly efficient in selecting the most reliable and economical oracles with a fair balance. • We propose BLOR, a Bayesian Bandit Learning model for Oracles Reliability. • BLOR identifies trustless and cost-efficient oracles. • BLOR integrates reinforcement learning to a Bayesian cost-driven reputation model. • BLOR is implemented in Ethereum and benchmarked against several algorithms. • BLOR shows a steady performance even in low to high noisy dynamic environments. [ABSTRACT FROM AUTHOR]

Many engineering and scientific problems in the real-world boil down to optimization problems, which are difficult to solve by using traditional methods. Meta-heuristics are appealing algorithms for solving optimization problems while keeping computational costs reasonable. The marine predators algorithm (MPA) is a modern optimization meta-heuristic, inspired by widespread Lévy and Brownian foraging strategies in ocean predators as well as optimal encounter rate strategies in biological interactions between predator and prey. However, MPA is not without its shortcomings. In this paper, a quasi-opposition based learning and Q-learning based marine predators algorithm (QQLMPA) is proposed. This offers multiple improvements over standard MPA. Primely, Q-learning allows MPA to fully use the information generated by previous iterations. And also, quasi-opposition based learning serves to increase population diversity, reducing the risk of convergence to inferior local optima. Numerical experiments demonstrate better performance by QQLMPA on 32 benchmark optimization functions and three engineering problems: designs of pressure vessel, hydro-static thrust bearing, and speed reducer. • Q-learning is introduced to MPA for adaptively choosing search mode. • Quasi-opposition learning is used to enhance the exploration of MPA. • The proposed optimizer can achieve great performance for continuous optimization. [ABSTRACT FROM AUTHOR]