• Title/Summary/Keyword: GAN(Generative Adversarial Network

Search Result 176, Processing Time 0.021 seconds

Detecting Malicious Social Robots with Generative Adversarial Networks

  • Wu, Bin;Liu, Le;Dai, Zhengge;Wang, Xiujuan;Zheng, Kangfeng
    • KSII Transactions on Internet and Information Systems (TIIS)
    • /
    • v.13 no.11
    • /
    • pp.5594-5615
    • /
    • 2019
  • Malicious social robots, which are disseminators of malicious information on social networks, seriously affect information security and network environments. The detection of malicious social robots is a hot topic and a significant concern for researchers. A method based on classification has been widely used for social robot detection. However, this method of classification is limited by an unbalanced data set in which legitimate, negative samples outnumber malicious robots (positive samples), which leads to unsatisfactory detection results. This paper proposes the use of generative adversarial networks (GANs) to extend the unbalanced data sets before training classifiers to improve the detection of social robots. Five popular oversampling algorithms were compared in the experiments, and the effects of imbalance degree and the expansion ratio of the original data on oversampling were studied. The experimental results showed that the proposed method achieved better detection performance compared with other algorithms in terms of the F1 measure. The GAN method also performed well when the imbalance degree was smaller than 15%.

Super Resolution Performance Analysis of GAN according to Feature Extractor (특징 추출기에 따른 SRGAN의 초해상 성능 분석)

  • Park, Sung-Wook;Kim, Jun-Yeong;Park, Jun;Jung, Se-Hoon;Sim, Chun-Bo
    • Proceedings of the Korea Information Processing Society Conference
    • /
    • 2022.11a
    • /
    • pp.501-503
    • /
    • 2022
  • 초해상이란 해상도가 낮은 영상을 해상도가 높은 영상으로 합성하는 기술이다. 딥러닝은 영상의 해상도를 높이는 초해상 기술에도 응용되며 실현은 2아4년에 발표된 SRCNN(Super Resolution Convolutional Neural Network) 모델로부터 시작됐다. 이후 오토인코더 (Autoencoders) 구조로는 SRCAE(Super Resolution Convolutional Autoencoders), 합성된 영상을 실제 영상과 통계적으로 구분되지 않도록 강제하는 GAN (Generative Adversarial Networks) 구조로는 SRGAN(Super Resolution Generative Adversarial Networks) 모델이 발표됐다. 모두 SRCNN의 성능을 웃도는 모델들이나 그중 가장 높은 성능을 끌어내는 SRGAN 조차 아직 완벽한 성능을 내진 못한다. 본 논문에서는 SRGAN의 성능을 개선하기 위해 사전 훈련된 특징 추출기(Pre-trained Feature Extractor) VGG(Visual Geometry Group)-19 모델을 변경하고, 기존 모델과 성능을 비교한다. 실험 결과, VGG-19 모델보다 윤곽이 뚜렷하고, 실제 영상과 더 가까운 영상을 합성할 수 있는 모델을 발견할 수 있을 것으로 기대된다.

Face Recognition Research Based on Multi-Layers Residual Unit CNN Model

  • Zhang, Ruyang;Lee, Eung-Joo
    • Journal of Korea Multimedia Society
    • /
    • v.25 no.11
    • /
    • pp.1582-1590
    • /
    • 2022
  • Due to the situation of the widespread of the coronavirus, which causes the problem of lack of face image data occluded by masks at recent time, in order to solve the related problems, this paper proposes a method to generate face images with masks using a combination of generative adversarial networks and spatial transformation networks based on CNN model. The system we proposed in this paper is based on the GAN, combined with multi-scale convolution kernels to extract features at different details of the human face images, and used Wasserstein divergence as the measure of the distance between real samples and synthetic samples in order to optimize Generator performance. Experiments show that the proposed method can effectively put masks on face images with high efficiency and fast reaction time and the synthesized human face images are pretty natural and real.

Generative Adversarial Network Pruning using Discriminator (판별자를 활용한 적대적 생성 신경망 프루닝)

  • Dongjun Lee;Seunghyun Lee;Byungcheol Song
    • Proceedings of the Korean Society of Broadcast Engineers Conference
    • /
    • 2022.11a
    • /
    • pp.123-125
    • /
    • 2022
  • 본 논문에서는 판별자를 활용하여 Image to Image translation(I2I) 분야에서 사용되는 적대적 생성 신경망(GAN)을 압축하는 방법을 제시한다. 우선, 잘 학습된 판별자와 생성자 사이의 adversarial loss 를 활용하여 생성자 내 필터들의 중요도 점수를 매겨준다. 그리고 생성자 내의 필터들을 중요도 점수를 기준으로 나열한 후 점수가 낮은 필터들을 제거하는 필터 프루닝을 한번 수행하여 적은 시간 비용으로 생성자를 압축한다. 마지막으로 지식 증류를 활용해 압축된 생성자를 학습시켜 기존의 생성자와 유사한 성능을 보이도록 하였다. 이 과정들을 통해 효과적이고 빠르게 GAN 모델을 압축할 수 있음을 확인하였다.

  • PDF

Anomaly Detection for User Action with Generative Adversarial Networks (적대적 생성 모델을 활용한 사용자 행위 이상 탐지 방법)

  • Choi, Nam woong;Kim, Wooju
    • Journal of Intelligence and Information Systems
    • /
    • v.25 no.3
    • /
    • pp.43-62
    • /
    • 2019
  • At one time, the anomaly detection sector dominated the method of determining whether there was an abnormality based on the statistics derived from specific data. This methodology was possible because the dimension of the data was simple in the past, so the classical statistical method could work effectively. However, as the characteristics of data have changed complexly in the era of big data, it has become more difficult to accurately analyze and predict the data that occurs throughout the industry in the conventional way. Therefore, SVM and Decision Tree based supervised learning algorithms were used. However, there is peculiarity that supervised learning based model can only accurately predict the test data, when the number of classes is equal to the number of normal classes and most of the data generated in the industry has unbalanced data class. Therefore, the predicted results are not always valid when supervised learning model is applied. In order to overcome these drawbacks, many studies now use the unsupervised learning-based model that is not influenced by class distribution, such as autoencoder or generative adversarial networks. In this paper, we propose a method to detect anomalies using generative adversarial networks. AnoGAN, introduced in the study of Thomas et al (2017), is a classification model that performs abnormal detection of medical images. It was composed of a Convolution Neural Net and was used in the field of detection. On the other hand, sequencing data abnormality detection using generative adversarial network is a lack of research papers compared to image data. Of course, in Li et al (2018), a study by Li et al (LSTM), a type of recurrent neural network, has proposed a model to classify the abnormities of numerical sequence data, but it has not been used for categorical sequence data, as well as feature matching method applied by salans et al.(2016). So it suggests that there are a number of studies to be tried on in the ideal classification of sequence data through a generative adversarial Network. In order to learn the sequence data, the structure of the generative adversarial networks is composed of LSTM, and the 2 stacked-LSTM of the generator is composed of 32-dim hidden unit layers and 64-dim hidden unit layers. The LSTM of the discriminator consists of 64-dim hidden unit layer were used. In the process of deriving abnormal scores from existing paper of Anomaly Detection for Sequence data, entropy values of probability of actual data are used in the process of deriving abnormal scores. but in this paper, as mentioned earlier, abnormal scores have been derived by using feature matching techniques. In addition, the process of optimizing latent variables was designed with LSTM to improve model performance. The modified form of generative adversarial model was more accurate in all experiments than the autoencoder in terms of precision and was approximately 7% higher in accuracy. In terms of Robustness, Generative adversarial networks also performed better than autoencoder. Because generative adversarial networks can learn data distribution from real categorical sequence data, Unaffected by a single normal data. But autoencoder is not. Result of Robustness test showed that he accuracy of the autocoder was 92%, the accuracy of the hostile neural network was 96%, and in terms of sensitivity, the autocoder was 40% and the hostile neural network was 51%. In this paper, experiments have also been conducted to show how much performance changes due to differences in the optimization structure of potential variables. As a result, the level of 1% was improved in terms of sensitivity. These results suggest that it presented a new perspective on optimizing latent variable that were relatively insignificant.

GAN-based Dance Performance Visual Background Generation Method using Emotion Analysis on Lyrics (가사의 감정 분석을 이용한 GAN 기반 댄스 공연 배경 생성 방법)

  • Yoon, Hyewon;Kwak, Jeonghoon;Sung, Yunsick
    • Proceedings of the Korea Information Processing Society Conference
    • /
    • 2020.05a
    • /
    • pp.530-531
    • /
    • 2020
  • 최근 인공지능을 활용하여 예술 작품에 몰입할 수 있도록 무대 효과를 디자인하는 연구가 진행되고 있다. 무대 효과 중에서 무대 배경은 공연의 분위기를 형성한다. 춤의 장르별로 무대 배경에 사용되는 이미지를 생성하기 위해 소셜 미디어 기반 무대 배경 생성 시스템이 있다. 하지만 같은 장르 춤은 동일한 무대 배경 이미지가 제공되는 문제가 있다. 같은 장르의 춤이지만 노래의 분위기를 반영하여 차별된 무대 배경 이미지를 제공하는 것이 필요하다. 본 논문은 노래 가사의 감정을 활용하여 Generative Adversarial Network(GAN)을 통해 각 노래의 분위기를 고려한 무대 배경 이미지를 생성하는 방법을 제안한다. GAN은 노래에 포함된 단락별 감정 단어를 추출하여 스타일을 생성하도록 학습된다. 학습된 GAN은 노래 가사에 포함된 감정 단어를 활용하여 곡의 분위기를 반영한 무대 배경 이미지를 생성한다. 노래 가사를 고려하여 무대 배경 이미지를 생성함으로써 곡의 분위기가 고려된 무대 배경 이미지 생성이 가능하다.

Data anomaly detection for structural health monitoring using a combination network of GANomaly and CNN

  • Liu, Gaoyang;Niu, Yanbo;Zhao, Weijian;Duan, Yuanfeng;Shu, Jiangpeng
    • Smart Structures and Systems
    • /
    • v.29 no.1
    • /
    • pp.53-62
    • /
    • 2022
  • The deployment of advanced structural health monitoring (SHM) systems in large-scale civil structures collects large amounts of data. Note that these data may contain multiple types of anomalies (e.g., missing, minor, outlier, etc.) caused by harsh environment, sensor faults, transfer omission and other factors. These anomalies seriously affect the evaluation of structural performance. Therefore, the effective analysis and mining of SHM data is an extremely important task. Inspired by the deep learning paradigm, this study develops a novel generative adversarial network (GAN) and convolutional neural network (CNN)-based data anomaly detection approach for SHM. The framework of the proposed approach includes three modules : (a) A three-channel input is established based on fast Fourier transform (FFT) and Gramian angular field (GAF) method; (b) A GANomaly is introduced and trained to extract features from normal samples alone for class-imbalanced problems; (c) Based on the output of GANomaly, a CNN is employed to distinguish the types of anomalies. In addition, a dataset-oriented method (i.e., multistage sampling) is adopted to obtain the optimal sampling ratios between all different samples. The proposed approach is tested with acceleration data from an SHM system of a long-span bridge. The results show that the proposed approach has a higher accuracy in detecting the multi-pattern anomalies of SHM data.

Analysis of Malware Image Data Augmentation based on GAN (GAN 기반의 악성코드 이미지 데이터 증강 분석)

  • Won-Jun Lee;ChangHoon Kang;Ah Reum Kang
    • Proceedings of the Korean Society of Computer Information Conference
    • /
    • 2024.01a
    • /
    • pp.99-100
    • /
    • 2024
  • 다양한 변종들의 존재와 잘 알려지지 않은 취약점을 이용한 공격은 악성코드 수집을 어렵게 하는 요인들이다. 부족한 악성코드 수를 보완하고자 생성 모델을 활용한 이미지 기반의 악성코드 데이터를 증강한 연구들도 존재하였다. 하지만 생성 모델이 실제 악성코드를 생성할 수 있는지에 대한 분석은 진행되지 않았다. 본 연구는 VGG-11 모델을 활용해 실제 악성코드와 생성된 악성코드 이미지의 이진 분류하였다. 실험 결과 VGG-11 모델은 99.9%의 정확도로 두 영상을 다르게 판단한다

  • PDF

The Effect of Training Patch Size and ConvNeXt application on the Accuracy of CycleGAN-based Satellite Image Simulation (학습패치 크기와 ConvNeXt 적용이 CycleGAN 기반 위성영상 모의 정확도에 미치는 영향)

  • Won, Taeyeon;Jo, Su Min;Eo, Yang Dam
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
    • /
    • v.40 no.3
    • /
    • pp.177-185
    • /
    • 2022
  • A method of restoring the occluded area was proposed by referring to images taken with the same types of sensors on high-resolution optical satellite images through deep learning. For the natural continuity of the simulated image with the occlusion region and the surrounding image while maintaining the pixel distribution of the original image as much as possible in the patch segmentation image, CycleGAN (Cycle Generative Adversarial Network) method with ConvNeXt block applied was used to analyze three experimental regions. In addition, We compared the experimental results of a training patch size of 512*512 pixels and a 1024*1024 pixel size that was doubled. As a result of experimenting with three regions with different characteristics,the ConvNeXt CycleGAN methodology showed an improved R2 value compared to the existing CycleGAN-applied image and histogram matching image. For the experiment by patch size used for training, an R2 value of about 0.98 was generated for a patch of 1024*1024 pixels. Furthermore, As a result of comparing the pixel distribution for each image band, the simulation result trained with a large patch size showed a more similar histogram distribution to the original image. Therefore, by using ConvNeXt CycleGAN, which is more advanced than the image applied with the existing CycleGAN method and the histogram-matching image, it is possible to derive simulation results similar to the original image and perform a successful simulation.

Study on 2D Sprite *3.Generation Using the Impersonator Network

  • Yongjun Choi;Beomjoo Seo;Shinjin Kang;Jongin Choi
    • KSII Transactions on Internet and Information Systems (TIIS)
    • /
    • v.17 no.7
    • /
    • pp.1794-1806
    • /
    • 2023
  • This study presents a method for capturing photographs of users as input and converting them into 2D character animation sprites using a generative adversarial network-based artificial intelligence network. Traditionally, 2D character animations have been created by manually creating an entire sequence of sprite images, which incurs high development costs. To address this issue, this study proposes a technique that combines motion videos and sample 2D images. In the 2D sprite generation process that uses the proposed technique, a sequence of images is extracted from real-life images captured by the user, and these are combined with character images from within the game. Our research aims to leverage cutting-edge deep learning-based image manipulation techniques, such as the GAN-based motion transfer network (impersonator) and background noise removal (U2 -Net), to generate a sequence of animation sprites from a single image. The proposed technique enables the creation of diverse animations and motions just one image. By utilizing these advancements, we focus on enhancing productivity in the game and animation industry through improved efficiency and streamlined production processes. By employing state-of-the-art techniques, our research enables the generation of 2D sprite images with various motions, offering significant potential for boosting productivity and creativity in the industry.