• Smart Structures and Systems
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• 제29권1호
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• pp.117-127
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• 2022

Data anomalies seriously threaten the reliability of the bridge structural health monitoring system and may trigger system misjudgment. To overcome the above problem, an efficient and accurate data anomaly detection method is desiderated. Traditional anomaly detection methods extract various abnormal features as the key indicators to identify data anomalies. Then set thresholds artificially for various features to identify specific anomalies, which is the artificial experience method. However, limited by the poor generalization ability among sensors, this method often leads to high labor costs. Another approach to anomaly detection is a data-driven approach based on machine learning methods. Among these, the bidirectional long-short memory neural network (BiLSTM), as an effective classification method, excels at finding complex relationships in multivariate time series data. However, training unprocessed original signals often leads to low computation efficiency and poor convergence, for lacking appropriate feature selection. Therefore, this article combines the advantages of the two methods by proposing a deep learning method with manual experience statistical features fed into it. Experimental comparative studies illustrate that the BiLSTM model with appropriate feature input has an accuracy rate of over 87-94%. Meanwhile, this paper provides basic principles of data cleaning and discusses the typical features of various anomalies. Furthermore, the optimization strategies of the feature space selection based on artificial experience are also highlighted.

• 스마트미디어저널
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• 제10권1호
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• pp.63-69
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• 2021

사람이 어떤 문장을 보고 그 문장에 대해 이해하는 것은 문장 안에서 주요한 단어를 이미지로 연상시켜 그 문장에 대해 이해한다. 이러한 연상과정을 컴퓨터가 할 수 있도록 하는 것을 text-to-image라고 한다. 기존 딥 러닝 기반 text-to-image 모델은 Convolutional Neural Network(CNN)-Long Short Term Memory(LSTM), bi-directional LSTM을 사용하여 텍스트의 특징을 추출하고, GAN에 입력으로 하여 이미지를 생성한다. 기존 text-to-image 모델은 텍스트 특징 추출에서 기본적인 임베딩을 사용하였으며, 여러 모듈을 사용하여 이미지를 생성하므로 학습 시간이 오래 걸린다. 따라서 본 연구에서는 자연어 처리분야에서 성능 향상을 보인 어텐션 메커니즘(Attention Mechanism)을 문장 임베딩에 사용하여 특징을 추출하고, 추출된 특징을 GAN에 입력하여 이미지를 생성하는 방법을 제안한다. 실험 결과 기존 연구에서 사용되는 모델보다 inception score가 높았으며 육안으로 판단하였을 때 입력된 문장에서 특징을 잘 표현하는 이미지를 생성하였다. 또한, 긴 문장이 입력되었을 때에도 문장을 잘 표현하는 이미지를 생성하였다.

• 정보처리학회논문지:소프트웨어 및 데이터공학
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• 제11권8호
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• pp.339-346
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• 2022

최근 화석연료의 무분별한 사용으로 인한 자원고갈 문제 및 기후변화 문제 등이 심각해짐에 따라 화석연료를 대체할 수 있는 신재생에너지에 대한 관심이 증가하고 있다. 특히 신재생에너지 중 태양광 에너지는 다른 신재생에너지원에 비해 고갈될 염려가 적고, 공간적인 제약이 크지 않아 전국적으로 수요가 증가하고 있다. 태양광 발전 시스템에서 생산된 전력을 효율적으로 사용하기 위해서는 보다 정확한 태양광 발전량 예측 모델이 필요하다. 이를 위하여 다양한 기계학습 및 심층학습 기반의 태양광 발전량 예측 모델이 제안되었지만, 심층학습 기반의 예측 모델은 모델 내부에서 일어나는 의사결정 과정을 해석하기가 어렵다는 단점을 보유하고 있다. 이러한 문제를 해결하기 위하여 설명 가능한 인공지능 기술이 많은 주목을 받고 있다. 설명 가능한 인공지능 기술을 통하여 예측 모델의 결과 도출 과정을 해석할 수 있다면 모델의 신뢰성을 확보할 수 있을 뿐만 아니라 해석된 도출 결과를 바탕으로 모델을 개선하여 성능 향상을 기대할 수도 있다. 이에 본 논문에서는 BiLSTM(Bidirectional Long Short-Term Memory)을 사용하여 모델을 구성하고, 모델에서 어떻게 예측값이 도출되었는지를 SHAP(SHapley Additive exPlanations)을 통하여 설명하는 설명 가능한 태양광 발전량 예측 기법을 제안한다.

• International Journal of Computer Science & Network Security
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• 제22권10호
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• pp.246-256
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• 2022

Recently, parents and teachers consider physical education as a minor subject for students in elementary and secondary schools. Physical education performance has become increasingly significant as parents and schools pay more attention to physical schooling. The sports mining with distribution analysis model considers different factors, including the games, comments, conversations, and connection made on numerous sports interests. Using different machine learning/deep learning approach, children's athletic and academic interests can be tracked over the course of their academic lives. There have been a number of studies that have focused on predicting the success of students in higher education. Sports interest prediction research at the secondary level is uncommon, but the secondary level is often used as a benchmark to describe students' educational development at higher levels. An Automated Student Interest Prediction on Sports Mining using DL Based Bi-directional Long Short-Term Memory model (BiLSTM) is presented in this article. Pre-processing of data, interest classification, and parameter tweaking are all the essential operations of the proposed model. Initially, data augmentation is used to expand the dataset's size. Secondly, a BiLSTM model is used to predict and classify user interests. Adagrad optimizer is employed for hyperparameter optimization. In order to test the model's performance, a dataset is used and the results are analysed using precision, recall, accuracy and F-measure. The proposed model achieved 95% accuracy on 400^th instances, where the existing techniques achieved 93.20% accuracy for the same. The proposed model achieved 95% of accuracy and precision for 60%-40% data, where the existing models achieved 93% for accuracy and precision.

• 한국정보과학회 언어공학연구회:학술대회논문집(한글 및 한국어 정보처리)
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• 한국정보과학회언어공학연구회 2018년도 제30회 한글 및 한국어 정보처리 학술대회
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• pp.352-357
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• 2018

본 논문에서는 한국어 프레임넷 분석기를 구축하기 위하여 한국어 프레임넷 데이터를 가공하여 공개하고, 한국어 프레임 분류 및 논항의 의미역 분류 문제를 해결하기 위한 방법을 제안한다. 프레임넷은 단어 단위가 아닌 단어들의 범위로 구성된 범위에 대해 어노테이션된 코퍼스라는 점에 착안하여, 어휘 및 논항의 내부 의미 정보와 외부 의미 정보, 그리고 프레임과 각 의미역들의 임베딩을 학습한 중첩 분할된 양방향 LSTM 모델을 사용하였다. 이를 통해 한국어 프레임 분류에서 72.48%, 논항의 의미역 분류에서 84.08%의 성능을 보였다. 또한 본 연구를 통해 한국어 프레임넷 데이터의 개선 방안을 논의한다.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제14권6호
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• pp.2444-2463
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• 2020

Significant detection of video can more rationally allocate computing resources and reduce the amount of computation to improve accuracy. Deep learning can extract the edge features of the image, providing technical support for video saliency. This paper proposes a new detection method. We combine the Convolutional Neural Network (CNN) and the Deep Bidirectional LSTM Network (DB-LSTM) to learn the spatio-temporal features by exploring the object motion information and object motion information to generate video. A continuous frame of significant images. We also analyzed the sample database and found that human attention and significant conversion are time-dependent, so we also considered the significance detection of video cross-frame. Finally, experiments show that our method is superior to other advanced methods.

• 한국정보통신학회논문지
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• 제26권4호
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• pp.633-636
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• 2022

The reduction of energy consumption at the base station (BS) has become more important recently. In this paper, we consider the adaptive muting of the antennas based on the predicted future traffic load to reduce the energy consumption where the number of active antennas is adaptively adjusted according to the predicted future traffic load. Given that traffic load is sequential data, three different RNN structures, namely long-short term memory (LSTM), gated recurrent unit (GRU), and bidirectional LSTM (Bi-LSTM) are considered for the future traffic load prediction. Through the performance evaluation based on the actual traffic load collected from the Afghanistan telecom company, we confirm that the traffic load can be estimated accurately and the overall power consumption can also be reduced significantly using the antenna musing.

• 한국정보처리학회:학술대회논문집
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• 한국정보처리학회 2020년도 추계학술발표대회
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• pp.1025-1027
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• 2020

태권도 경기와 같이 동작의 정확한 기술을 판별하여 유효득점화하는 시스템에서는 점수 체계의 정확성과 전문성이 필요하다. 기존에 시행되었던 심판 판정은 객관성과 신뢰성의 결여 문제가 존재하여 이를 대체하기 위한 방법으로 전자호구가 도입되었다. 하지만 전자호구는 타격 강도에 따라 분류되는 문제로 인해 태권도 기술이 아닌 변칙 발차기 기술에서도 유효득점이 처리되는 문제가 발생하였다. 본 논문에서는 변칙 발차기와 일반 발차기를 분류하여 변칙 발차기에서의 유효득점을 무효 득점화 시키기 위한 분류 모델을 제안하였다. 순환 신경망 모델인 LSTM을 이용하여 변칙 발차기와 일반 발차기를 분류하였으며 94.90%의 정확도를 보였다.

• Computers and Concrete
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• 제24권6호
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• pp.555-560
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• 2019

During the application of shotcrete, a part of the concrete bounces back after hitting to the surface, the reinforcement or previously sprayed concrete. This rebound material is definitely not added to the mixture and considered as waste. In this study, a deep neural network model was developed to predict the rebound material during shotcrete application. The factors affecting rebound and the datasets of these parameters were obtained from previous experiments. The Long Short-Term Memory (LSTM) architecture of the proposed deep neural network model was used in accordance with this data set. In the development of the proposed four-tier prediction model, the dataset was divided into 90% training and 10% test. The deep neural network was modeled with 11 dependents 1 independent data by determining the most appropriate hyper parameter values for prediction. Accuracy and error performance in success performance of LSTM model were evaluated over MSE and RMSE. A success of 93.2% was achieved at the end of training of the model and a success of 85.6% in the test. There was a difference of 7.6% between training and test. In the following stage, it is aimed to increase the success rate of the model by increasing the number of data in the data set with synthetic and experimental data. In addition, it is thought that prediction of the amount of rebound during dry-mix shotcrete application will provide economic gain as well as contributing to environmental protection.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제13권5호
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• pp.2674-2697
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• 2019

Identity authentication is a crucial line of defense for network security, and passwords are still the mainstream of identity authentication. So far trawling password attacking has been extensively studied, but the research related with personal information is always sporadic. Probabilistic context-free grammar (PCFG) and Markov chain-based models perform greatly well in trawling guessing. In this paper we propose a systematic targeted attacking model based on structure partition and string reorganization by migrating the above two models to targeted attacking, denoted as TG-SPSR. In structure partition phase, besides dividing passwords to basic structure similar to PCFG, we additionally define a trajectory-based keyboard pattern in the basic grammar and introduce index bits to accurately characterize the position of special characters. Moreover, we also construct a BiLSTM recurrent neural network classifier to characterize the behavior of password reuse and modification after defining nine kinds of modification rules. Extensive experimental results indicate that in online attacking, TG-SPSR outperforms traditional trawling attacking algorithms by average about 275%, and respectively outperforms its foremost counterparts, Personal-PCFG, TarGuess-I, by about 70% and 19%; In offline attacking, TG-SPSR outperforms traditional trawling attacking algorithms by average about 90%, outperforms Personal-PCFG and TarGuess-I by 85% and 30%, respectively.