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본 논문에서는 커널 Extreme Learning Machine을 기반으로 하여 최적화 기법들 중의 하나인 입자 군집 최적화 기법을 이용한 설계 기법을 제시한다. 제안된 Kernel Extreme Learning Machine은 기존에 사용되어지는 뉴럴 네트워크의 단점을 개선한 네트워크이다. 다시 말하면, 뉴럴 네트워크의 단점인 느린 학습속도를 개선한 네 트워크이다. 일반적으로 뉴럴 네트워크의 히든 노드들은 랜덤 초기화 후 오류 역전파 알고리즘을 이용하여 학습 한다. 이와 같은 오류 역전파 알고리즘은 매우 느린 학습속도를 보인다. 이와 같은 단점을 해결하기 위하여, Kernel Extreme Learning Machine의 히든 노드들은 랜덤 초기화 되고 학습되지 않고 출력층의 연결 하중만 학습 되어진다. 이와 같은 장점을 가진 Kernel Extreme Learning Machine의 구조를 최적화하기 위하여 입자 군집 최적 화 기법을 사용한다. 제안된 설계 방법을 적용하여 설계된 모델의 일반화 성능의 우수성을 보이기 위하여, 다수 의 머신러닝 데이터들을 이용하여 실험하고 실험을 통해 얻은 결과를 비교 평가하였다.

In this paper, we proposed the design method of Extreme Learning Machine which is optimized by using Particle Swarm Optimization Technique. Extreme Learning Machine is the improved version of the conventional neural networks which have a very slow learning speed based on the back-propagation algorithm. In the conventional neural networks, the connection weights between the input layer and the hidden layers are initialized randomly and then optimized by using the gradient decent method. The speed of the learning method for the conventional neural networks is slow. In order to overcome the drawback of the conventional neural networks, the connection weights of the hidden nodes are just initialized randomly and will not be optimized, and the only connection weights of the output nodes are learned by using least square estimation not the iterative learning method. In addition, we use Particle Swarm Optimization to optimize the proposed Extreme Learning Machine. Several machine learning bench-mark data sets are used to show the generalization performance of the proposed design method and to compare their performance with the other already studied models.

With social media growing fast, user-generated content (UGC) has become a key factor in influencing how consumers decide what to buy, especially in the travel and hospitality sector. But there are a lot of fake and extreme reviews, which are making it hard for customers to make the right choice and making competition in the market unfair. The present study focuses on YouTube, a platform with high global activity, and proposes a systematic solution that combines Natural Language Processing (NLP) and machine learning methods (e.g., VADER Sentiment Analysis, Support Vector Machine SVM, and LDA Topic Modelling) for identifying and filtering fake and extreme remarks in hotel reviews. This approach has been shown to enhance the automation and precision of review screening processes. Furthermore, it provides a theoretical foundation and practical methodologies to improve the online information ecology, thereby enhancing the quality of user decision-making.

본 연구는 벡터자기회귀모형과 머신러닝 ELM 모형을 이용하여 오피스 임대료 예측력 이 우수한 모형을 파악하고자 한다. 본 연구에서는 오피스 임대료, 공실률, 회사채수익률, 산업생산지수와 건축착공실적을 변수로 사용하였으며 시간적 범위는 2003년 2분기부터 2014년 4분기까지로, 공간적 범위는 서울시 도심권역, 강남권역, 마포/여의도권역으로 설 정하였다. 분석결과, 지역별로 일부분 차이는 존재하였으나 대체적으로 오피스 임대료는 회사채수익률과 건축착공실적 충격에 부(-)의 반응을 나타낸 반면 공실률과 산업생산지수 충격에는 정(+)의 반응을 나타냈다. 머신러닝 ELM모형과 VAR모형의 평균제곱오차(MSE), 평균제곱근오차(RMSE) 및 평균절대백분율오차(MAPE)를 비교 분석한 결과, 머신러닝의 ELM모형의 예측력이 VAR모형보다 우수함을 실증적으로 알 수가 있었고 예측기간 초기 의 예측력이 우수하다는 것을 알수가 있었다.

In this study, office rent rate is predicted using vector autoregression(VAR) model and extreme learning machine(ELM), and a model with excellent predictive power is to be identified. The variables used in this study are office rent rate, vacancy rate, industrial production index, corporate bond yield and construction start performance. The temporal range is from the 2nd quarter of 2003 to the 4th quarter of 2014, and the spatial range is the downtown area, Gangnam area, Mapo/Yeouido area in Seoul. As a result of analysis, there were some differences by region, but generally, office rental rates showed a negative (-) response to the impact of corporate bond yield and construction start performance, while the vacancy rate and industrial production index impact showed a positive (+) response. . As a result of comparing and analyzing the root mean square error (RMSE), mean square error (MSE) and mean absolute percent error (MAPE) of ELM model and VAR model, it was empirically shown that the predictive power of the ELM model is superior to the VAR model. And the predictive power of the initial period of the prediction period was excellent.

In this paper, a general voice activity detection (VAD) method based on pattern recognition is proposed, and a specific algorithm of endpoint detection is researched. In this method, the Extreme Learning Machine (ELM) and Genetic Algorithm (GA) optimization Support Vector Machine (SVM) is used as the training and recognition model. The simulation results indicates that ELM and GA-SVM have the same superior endpoint detection accuracy, and recognition time were similar, but the training time of ELM only up to a 1/2000 of the GA-SVM, the robustness of ELM and GA-SVM is greatly improved in noisy environment compare with the traditional VAD that depends on time-domain energy and zero crossing rate.

In order to lower the classification cost and improve the performance of the classifier, this paper proposes the approach of the dynamic cost-sensitive ensemble classification based on extreme learning machine for imbalanced massive data streams (DCECIMDS). Firstly, this paper gives the method of concept drifts detection by extracting the attributive characters of imbalanced massive data streams. If the change of attributive characters exceeds threshold value, the concept drift occurs. Secondly, we give Cost-sensitive extreme learning machine algorithm, and the optimal cost function is defined by the dynamic cost matrix. Build the cost-sensitive classifiers model for imbalanced massive data streams under MapReduce, and the data streams are processed in parallel. At last, the weighted cost-sensitive ensemble classifier is constructed, and the dynamic cost-sensitive ensemble classification based on extreme learning machine classification is given. The experiments demonstrate that the proposed ensemble classifier under the MapReduce framework can reduce the average misclassification cost and can make the classification results more reliable. DCECIMDS has high performance by comparing to the other classification algorithms for imbalanced data streams and can effectively deal with the concept drift.

Thought Extreme Learning Machine-Radial Basis Function(ELM-RBF) can be used easily and can complete learning phase at very fast speed and provide more compact network than classical Extreme Learning Machine(ELM), it still has some room to improvement. Micro-Genetic Algorithms(uGA) improved calculated speed while inherits the Genetic Algorithms advantage of good for optimization and overall search. Considered on these, the paper designed a optimization strategy for ELM-RBF neural network based on uGA. In particular, based on classical RBF-ELM, we use real-u GA algorithm to optimize ELM-RBF hidden layer neurons center and biases value. Experiments results show that ELM-RBF-uGA has better recognition and prediction performance than classical ELM-RBF.

In this paper, we propose a new hybrid intelligent modeling using context clustering and Extreme Learning Machine (ELM) mechanism. It has been a sensitive issue that the ELM mechanism assigns initial parameters randomly, despite of its superior performance. The proposed approach focuses on initial parameters determination of the modeling to improve the accuracy of the ELM mechanism, through removing randomness of assignment. To accomplish it, a context clustering based on Gaussian Mixture Model (GMM), considering a relationship between input-output spaces will be adopted to a Radial Basis Function Network (RBFN) of the ELM. In addition, the proposed approach will reduce the randomness of results from the original ELM. Simulations and the results show usefulness of the proposed approach with improved performance accuracy.

We introduce a fast and effective algorithm extreme learning machine (ELM) and apply it to image denoising. GA-ELM algorithm we proposed uses genetic algorithm(GA) to decide weights and bias in the ELM. It has better global optimal characteristics than traditional optimal ELM algorithm. In this paper, we used GA-ELM to do image denosing researching work. Firstly, this paper uses training samples to train GA-ELM as the noise detector. Then, we utilize the well-trained GA-ELM to recognize noise pixels in target image. And at last, an adaptive weighted average algorithm is used to recover noise pixels recognized by GA-ELM. Experiment data shows that this algorithm has better performance than other denosing algorithm.

Due to its importance in many applications, the incomplete data mining has received increasing attention in recent years, but there has been little study of the cost-sensitive classification on incomplete data. Therefore this paper proposes the dynamic cost-sensitive extreme learning machine for classification of incomplete data based on the deep imputation network (DCELMIDC). Firstly, we propose an approach for incomplete data imputation based on the deep imputation network model, and offer the cost-sensitive extreme learning machine. Secondly, this paper introduces dynamic misclassification and test cost, and gives the chromosome coding and an evaluation method of the optimal cost. At last, on the basis of the genetic algorithm, the dynamic cost-sensitive extreme learning machine classification algorithm for mining incomplete data is given, which can search the optimal misclassification and test cost in cost spaces. The experiment results show that DCELMIDC is effective and feasible for classification of incomplete data, and can reduce the total cost.

Human activity recognition is a main research area of context-aware computing, and is widely used in many applications, such as smart home and elderly care. Smart phone-based human activity recognition is very popular by making use of the embedded inertial sensors. However, there exists the problems of misclassification activities, and how to effectively apply the model trained by known users to new users. To solve these two problems, in this paper, we proposed a novel approach, Uncertainty Sampling based posterior Probability Extreme Learning Machine (USP-ELM), by introducing two strategies: first, we transfer the actual outputs of ELM to posterior probabilities for each instances, and then use uncertainty sampling strategy for confidence level assignment to adapt the training model and improve the classification accuracy. Experimental results show that the proposed approach is more efficient, compared with the existing ELMs.

With the large-scale application of high dimensional gene expression data which exists lots of redundant information, it may waste a lot of time in feature selection and classification. By analyzing the process of MapReduce computing paradigms on cloud platform, it is found that the feature selection which through parallel and distributed computing in MapReduce combined with extreme learning machine is appropriate for constructing a recognition method. This paper proposed a MapReduce algorithm on high gene feature for parallel and distributed selection and classification, aiming to save time resources to make a higher accuracy in training process on large scale gene datasets. Simulation experiments on gene datasets show that the running time on cloud platform is greatly shortened by the time promising the high classification accuracy.

본 논문에서는 인공 신경망의 일종인 Extreme Learning Machine의 학습 알고리즘을 기반으로 하여 노이즈에 강한 특성을 보이는 퍼지 집합 이론을 이용한 새로운 패턴 분류기를 제안 한다. 기존 인공 신경망에 비해 학습속도가 매우 빠르며, 모델의 일반화 성능이 우수하다고 알려진 Extreme Learning Machine의 학습 알고리즘을 퍼지 패턴 분류기에 적용하여 퍼지 패턴 분류기의 학습 속도와 패턴 분류 일반화 성능을 개선 한다. 제안된 퍼지패턴 분류기의 학습 속도와 일반화 성능을 평가하기 위하여, 다양한 머신 러닝 데이터 집합을 사용한다.

In this paper, we introduce a new pattern classifier which is based on the learning algorithm of Extreme Learning Machine the sort of artificial neural networks and fuzzy set theory which is well known as being robust to noise. The learning algorithm used in Extreme Learning Machine is faster than the conventional artificial neural networks. The key advantage of Extreme Learning Machine is the generalization ability for regression problem and classification problem. In order to evaluate the classification ability of the proposed pattern classifier, we make experiments with several machine learning data sets.

Online voltage stability monitoring using real-time measurements is one of the most important tasks in a smart grid system to maintain the grid stability. Loading margin is a good indicator for assessing the voltage stability level. This paper presents an Extreme Learning Machine (ELM) approach for estimation of voltage stability level under credible contingencies using real-time measurements from Phasor Measurement Units (PMUs). PMUs enable a much higher data sampling rate and provide synchronized measurements of real-time phasors of voltages and currents. Depth First (DF) algorithm is used for optimally placing the PMUs. To make the ELM approach applicable for a large scale power system problem, Mutual information (MI)-based feature selection is proposed to achieve the dimensionality reduction. MI-based feature selection reduces the number of network input features which reduces the network training time and improves the generalization capability. Voltage magnitudes and phase angles received from PMUs are fed as inputs to the ELM model. IEEE 30-bus test system is considered for demonstrating the effectiveness of the proposed methodology for estimating the voltage stability level under various loading conditions considering single line contingencies. Simulation results validate the suitability of the technique for fast and accurate online voltage stability assessment using PMU data.

An extreme learning machine (ELM) is a recently proposed learning algorithm for a single-layer feed forward neural network. In this paper we studied the ensemble of ELM by using a bagging algorithm for facial expression recognition (FER). Facial expression analysis is widely used in the behavior interpretation of emotions, for cognitive science, and social interactions. This paper presents a method for FER based on the histogram of orientation gradient (HOG) features using an ELM ensemble. First, the HOG features were extracted from the face image by dividing it into a number of small cells. A bagging algorithm was then used to construct many different bags of training data and each of them was trained by using separate ELMs. To recognize the expression of the input face image, HOG features were fed to each trained ELM and the results were combined by using a majority voting scheme. The ELM ensemble using bagging improves the generalized capability of the network significantly. The two available datasets (JAFFE and CK+) of facial expressions were used to evaluate the performance of the proposed classification system. Even the performance of individual ELM was smaller and the ELM ensemble using a bagging algorithm improved the recognition performance significantly.

본 논문에서는 Extreme Learning Machine(ELM)을 이용한 자기부상시스템 모델링 기법을 제안한다. 자기부상시스템의 모델링을 위하여 일반적으로 테일러 급수를 이용한 선형화 모델이 사용되어져 왔으나, 이런 수학적 기법의 경우 자기부상시스템의 비선형 반영에 한계가 있다는 단점을 가지고 있다. 이러한 단점을 극복하기 위해 본 논문에서는 학습시간이 빠른 특성을 가진 ELM을 이용한 자기부상시스템의 모델링 기법을 제안한다. 제안된 기법은 입력 가중치들과 은닉 바이어스들의 초기값을 무작위로 선택하고 출력 가중치들은 Moore-Penrose의 일반화된 역행렬 방법을 통하여 구해진다. 실험을 통하여 제안된 알고리즘이 자기부상시스템의 모델링에서 수학적 기법에 비해 우수한 성능을 보임을 알 수 있었다.

In this paper, a new modeling method of a magnetic levitation(Maglev) system using extreme learning machine(ELM) is proposed. The linearized methods using Taylor Series expansion has been used for modeling of a Maglev system. However, the numerical method has some drawbacks when dealing with the components with high nonlinearity of a Maglev system. To overcome this problem, we propose a new modeling method of the Maglev system with electro magnetic suspension, which is based on ELM with fast learning time than conventional neural networks. In the proposed method, the initial input weights and hidden biases of the method are usually randomly chosen, and the output weights are analytically determined by using Moore-Penrose generalized inverse. matrix Experimental results show that the proposed method can achieve better performance for modeling of Maglev system than the previous numerical method.

본 연구에서는 안정적인 물 공급과 에너지의 효율적 사용을 위한 단기 물 수요예측알고리즘 개발에 있어서, 지방 소도시 지역의 물 공급패턴에 대한 영향인자를 도출하기 위하여 기상환경인자와 과거 물 공급량에 대한 상관성 분석을 실시하였다. 그리고, 신경회로망 이론 중 ELM알고리즘을 적용한 단기 물 수요예측알고리즘을 개발하여 현장 적용성을 검토하고자 한다.

In this paper, we propose pattern recognition algorithm for activities of daily living by adopting extreme learning machine based on single layer feedforward networks(SLFNs) to the signal from bidirectional accelerometer. For activity classification, 20 persons are participated and we acquire 6, types of signals at standing, walking, running, sitting, lying, and falling. Then, we design input vector using reduced model for ELM input. In ELM classification results, we can find accuracy change by increasing the number of hidden neurons. As a result, we find the accuracy is increased by increasing the number of hidden neuron. ELM is able to classify more than 80 % accuracy for experimental data set when the number of hidden is more than 20.

본 논문에서는 일반적인 신경회로망의 단점인 느린 학습속도를 획기적으로 개선한 네트워크인 Extreme Learning Machine과 전문가들의 언어적 정보들을 기술 할 수 있는 퍼지 이론을 접목한 퍼지 Extreme Learning Machine을 최적화하기 위하여 Particle Swarm Optimization 알고리즘을 이용하였다. 퍼지 Extreme Learning Machine의 활성화 함수를 일반적인 시그모이드 함수를 사용하지 않고, 퍼지 C-Means 클러스터링 알고리즘의 활성화 레벨 함수를 이용하였다. Particle Swarm Optimization 알고리즘과 같은 최적화 알고리즘을 통하여 퍼지 Extreme Learning Machine의 활성화 함수의 파라미터들을 최적화 한다. Particle Swarm Optimization과 같은 최적화 알고리즘을 통한 제안된 모델의 최적화 하고 최적화된 모델의 분류성능을 평가하기 위하여 다양한 머신 러닝 데이터 집합을 사용하여 평가한다.

In this paper, optimization technique such as particle swarm optimization was used to optimize the parameters of fuzzy Extreme Learning Machine. While the learning speed of conventional neural networks is very slow, that of Extreme Learning Machine is very fast. Fuzzy Extreme Learning Machine is composed of the Extreme Learning Machine with very fast learning speed and fuzzy logic which can represent the linguistic information of the field experts. The general sigmoid function is used for the activation function of Extreme Learning Machine. However, the activation function of Fuzzy Extreme Learning Machine is the membership function which is defined in the procedure of fuzzy C-Means clustering algorithm. We optimize the parameters of the membership functions by using optimization technique such as Particle Swarm Optimization. In order to validate the classification capability of the proposed classifier, we make several experiments with the various machine learning datas.

최근 단일 은닉층을 갖는 전방향 신경회로망 구조로, 기존의 경사 기반 학습알고리즘들보다 학습 속도가 매우 우수한 ELM(Extreme Learning Machine)이 제안되었다. ELM 알고리즘은 입력 가중치들과 은닉 바이어스들의 초기 값을 무작위로 선택하고 출력 가중치들은 Moore-Penrose(MP) 일반화된 역행렬 방법을 통하여 구해진다. 그러나 입력 가중치들과 은닉층 바이어스들의 초기 값 선택이 어렵다는 단점을 갖고 있다. 본 논문에서는 최적화 알고리즘 중 박테리아 생존(Bacterial Foraging) 알고리즘의 수정된 구조를 이용하여 ELM의 초기 입력 가중치들과 은닉층 바이어스들을 선택하는 개선된 방법을 제안하였다. 실험을 통하여 제안된 알고리즘이 많은 입력 데이터를 가지는 문제들에 대하여 성능이 우수함을 보였다.

Recently, Extreme learning machine(ELM), a novel learning algorithm which is much faster than conventional gradient-based learning algorithm, was proposed for single-hidden-layer feedforward neural networks. The initial input weights and hidden biases of ELM are usually randomly chosen, and the output weights are analytically determined by using Moore-Penrose(MP) generalized inverse. But it has the difficulties to choose initial input weights and hidden biases. In this paper, an advanced method using the bacterial foraging algorithm to adjust the input weights and hidden biases is proposed. Experiment at results show that this method can achieve better performance for problems having higher dimension than others.