• 제목/요약/키워드: computer models

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Generative Adversarial Networks: A Literature Review

  • Cheng, Jieren;Yang, Yue;Tang, Xiangyan;Xiong, Naixue;Zhang, Yuan;Lei, Feifei
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제14권12호
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    • pp.4625-4647
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    • 2020
  • The Generative Adversarial Networks, as one of the most creative deep learning models in recent years, has achieved great success in computer vision and natural language processing. It uses the game theory to generate the best sample in generator and discriminator. Recently, many deep learning models have been applied to the security field. Along with the idea of "generative" and "adversarial", researchers are trying to apply Generative Adversarial Networks to the security field. This paper presents the development of Generative Adversarial Networks. We review traditional generation models and typical Generative Adversarial Networks models, analyze the application of their models in natural language processing and computer vision. To emphasize that Generative Adversarial Networks models are feasible to be used in security, we separately review the contributions that their defenses in information security, cyber security and artificial intelligence security. Finally, drawing on the reviewed literature, we provide a broader outlook of this research direction.

Testing the Equality of Two Linear Regression Models : Comparison between Chow Test and a Permutation Test

  • Um, Yonghwan
    • 한국컴퓨터정보학회논문지
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    • 제26권8호
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    • pp.157-164
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    • 2021
  • 회귀분석은 반응변수와 예측변수들 간의 관련성을 설명하기 위해 사용되는 잘 알려진 통계 테크닉이다. 특히 연구자들은 두 개의 독립 모집단에서의 모형들의 회귀계수들(절편과 기울기)을 비교하는데 관심이 있다. Gregory Chow에 의해 제안된 Chow 검정은 회귀모형들을 비교하고 선형회귀모형 안에 구조적 브레이크가 존재하는지를 검정하기 위해 보통 사용되는 방법들 중의 하나이다. 본 연구에서는 두 독립 선형회귀모형들의 등가성을 검정하기 위해 퍼뮤테이션 방법을 제안하고 Chow 검정과 비교한다. 그리고 퍼뮤테이션 검정과 Chow 검정의 검정력을 조사하기 위해 시물레이션 연구를 진행하였다.

Modern Methods of Text Analysis as an Effective Way to Combat Plagiarism

  • Myronenko, Serhii;Myronenko, Yelyzaveta
    • International Journal of Computer Science & Network Security
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    • 제22권8호
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    • pp.242-248
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    • 2022
  • The article presents the analysis of modern methods of automatic comparison of original and unoriginal text to detect textual plagiarism. The study covers two types of plagiarism - literal, when plagiarists directly make exact copying of the text without changing anything, and intelligent, using more sophisticated techniques, which are harder to detect due to the text manipulation, like words and signs replacement. Standard techniques related to extrinsic detection are string-based, vector space and semantic-based. The first, most common and most successful target models for detecting literal plagiarism - N-gram and Vector Space are analyzed, and their advantages and disadvantages are evaluated. The most effective target models that allow detecting intelligent plagiarism, particularly identifying paraphrases by measuring the semantic similarity of short components of the text, are investigated. Models using neural network architecture and based on natural language sentence matching approaches such as Densely Interactive Inference Network (DIIN), Bilateral Multi-Perspective Matching (BiMPM) and Bidirectional Encoder Representations from Transformers (BERT) and its family of models are considered. The progress in improving plagiarism detection systems, techniques and related models is summarized. Relevant and urgent problems that remain unresolved in detecting intelligent plagiarism - effective recognition of unoriginal ideas and qualitatively paraphrased text - are outlined.

High-Capacity Robust Image Steganography via Adversarial Network

  • Chen, Beijing;Wang, Jiaxin;Chen, Yingyue;Jin, Zilong;Shim, Hiuk Jae;Shi, Yun-Qing
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제14권1호
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    • pp.366-381
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    • 2020
  • Steganography has been successfully employed in various applications, e.g., copyright control of materials, smart identity cards, video error correction during transmission, etc. Deep learning-based steganography models can hide information adaptively through network learning, and they draw much more attention. However, the capacity, security, and robustness of the existing deep learning-based steganography models are still not fully satisfactory. In this paper, three models for different cases, i.e., a basic model, a secure model, a secure and robust model, have been proposed for different cases. In the basic model, the functions of high-capacity secret information hiding and extraction have been realized through an encoding network and a decoding network respectively. The high-capacity steganography is implemented by hiding a secret image into a carrier image having the same resolution with the help of concat operations, InceptionBlock and convolutional layers. Moreover, the secret image is hidden into the channel B of carrier image only to resolve the problem of color distortion. In the secure model, to enhance the security of the basic model, a steganalysis network has been added into the basic model to form an adversarial network. In the secure and robust model, an attack network has been inserted into the secure model to improve its robustness further. The experimental results have demonstrated that the proposed secure model and the secure and robust model have an overall better performance than some existing high-capacity deep learning-based steganography models. The secure model performs best in invisibility and security. The secure and robust model is the most robust against some attacks.

최신 기계번역 사후 교정 연구 (Recent Automatic Post Editing Research)

  • 문현석;박찬준;어수경;서재형;임희석
    • 디지털융복합연구
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    • 제19권7호
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    • pp.199-208
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    • 2021
  • 기계번역 사후교정이란, 기계번역 문장에 포함된 오류를 자동으로 교정하기 위해 제안된 연구 분야이다. 이는 번역 시스템과 관계없이 번역문의 품질을 높이는 오류 교정 모델을 생성하는 목적을 가진 연구로, 훈련을 위해 소스문장, 번역문, 그리고 이를 사람이 직접 교정한 문장이 활용된다. 특히, 최신 기계번역 사후교정 연구에서는 사후교정 데이터를 통한 학습을 진행하기 이전에, 사전학습된 다국어 언어모델을 활용하는 방법이 적용되고 있다. 이에 본 논문은 최신 연구들에서 활용되고 있는 다국어 사전학습 언어모델들과 함께, 해당 모델을 도입한 각 연구에서의 구체적인 적용방법을 소개한다. 나아가 이를 기반으로, 번역 모델과 mBART모델을 활용하는 향후 연구 방향을 제안한다.

Comparative Study of PSO-ANN in Estimating Traffic Accident Severity

  • Md. Ashikuzzaman;Wasim Akram;Md. Mydul Islam Anik;Taskeed Jabid;Mahamudul Hasan;Md. Sawkat Ali
    • International Journal of Computer Science & Network Security
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    • 제23권8호
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    • pp.95-100
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    • 2023
  • Due to Traffic accidents people faces health and economical casualties around the world. As the population increases vehicles on road increase which leads to congestion in cities. Congestion can lead to increasing accident risks due to the expansion in transportation systems. Modern cities are adopting various technologies to minimize traffic accidents by predicting mathematically. Traffic accidents cause economical casualties and potential death. Therefore, to ensure people's safety, the concept of the smart city makes sense. In a smart city, traffic accident factors like road condition, light condition, weather condition etcetera are important to consider to predict traffic accident severity. Several machine learning models can significantly be employed to determine and predict traffic accident severity. This research paper illustrated the performance of a hybridized neural network and compared it with other machine learning models in order to measure the accuracy of predicting traffic accident severity. Dataset of city Leeds, UK is being used to train and test the model. Then the results are being compared with each other. Particle Swarm optimization with artificial neural network (PSO-ANN) gave promising results compared to other machine learning models like Random Forest, Naïve Bayes, Nearest Centroid, K Nearest Neighbor Classification. PSO- ANN model can be adopted in the transportation system to counter traffic accident issues. The nearest centroid model gave the lowest accuracy score whereas PSO-ANN gave the highest accuracy score. All the test results and findings obtained in our study can provide valuable information on reducing traffic accidents.

A SCORM-based e-Learning Process Control Model and Its Modeling System

  • Kim, Hyun-Ah;Lee, Eun-Jung;Chun, Jun-Chul;Kim, Kwang-Hoon Pio
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제5권11호
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    • pp.2121-2142
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    • 2011
  • In this paper, we propose an e-Learning process control model that aims to graphically describe and automatically generate the manifest of sequencing prerequisites in packaging SCORM's content aggregation models. In specifying the e-Learning activity sequencing, SCORM provides the concept of sequencing prerequisites to be manifested on each e-Learning activity of the corresponding tree-structured content organization model. However, the course developer is required to completely understand the SCORM's complicated sequencing prerequisites and other extensions. So, it is necessary to achieve an efficient way of packaging for the e-Learning content organization models. The e-Learning process control model proposed in this paper ought to be an impeccable solution for this problem. Consequently, this paper aims to realize a new concept of process-driven e-Learning content aggregating approach supporting the e-Learning process control model and to implement its e-Learning process modeling system graphically describing and automatically generating the SCORM's sequencing prerequisites. Eventually, the proposed model becomes a theoretical basis for implementing a SCORM-based e-Learning process management system satisfying the SCORM's sequencing prerequisite specifications. We strongly believe that the e-Learning process control model and its modeling system achieve convenient packaging in SCORM's content organization models and in implementing an e-Learning management system as well.

Detection of Multiple Salient Objects by Categorizing Regional Features

  • Oh, Kang-Han;Kim, Soo-Hyung;Kim, Young-Chul;Lee, Yu-Ra
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제10권1호
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    • pp.272-287
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    • 2016
  • Recently, various and effective contrast based salient object detection models to focus on a single target have been proposed. However, there is a lack of research on detection of multiple objects, and also it is a more challenging task than single target process. In the multiple target problem, we are confronted by new difficulties caused by distinct difference between properties of objects. The characteristic of existing models depending on the global maximum distribution of data point would become a drawback for detection of multiple objects. In this paper, by analyzing limitations of the existing methods, we have devised three main processes to detect multiple salient objects. In the first stage, regional features are extracted from over-segmented regions. In the second stage, the regional features are categorized into homogeneous cluster using the mean-shift algorithm with the kernel function having various sizes. In the final stage, we compute saliency scores of the categorized regions using only spatial features without the contrast features, and then all scores are integrated for the final salient regions. In the experimental results, the scheme achieved superior detection accuracy for the SED2 and MSRA-ASD benchmarks with both a higher precision and better recall than state-of-the-art approaches. Especially, given multiple objects having different properties, our model significantly outperforms all existing models.

Accuracy evaluation of dental models manufactured by CAD/CAM milling method and 3D printing method

  • Jeong, Yoo-Geum;Lee, Wan-Sun;Lee, Kyu-Bok
    • The Journal of Advanced Prosthodontics
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    • 제10권3호
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    • pp.245-251
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    • 2018
  • PURPOSE. To evaluate the accuracy of a model made using the computer-aided design/computer-aided manufacture (CAD/CAM) milling method and 3D printing method and to confirm its applicability as a work model for dental prosthesis production. MATERIALS AND METHODS. First, a natural tooth model (ANA-4, Frasaco, Germany) was scanned using an oral scanner. The obtained scan data were then used as a CAD reference model (CRM), to produce a total of 10 models each, either using the milling method or the 3D printing method. The 20 models were then scanned using a desktop scanner and the CAD test model was formed. The accuracy of the two groups was compared using dedicated software to calculate the root mean square (RMS) value after superimposing CRM and CAD test model (CTM). RESULTS. The RMS value ($152{\pm}52{\mu}m$) of the model manufactured by the milling method was significantly higher than the RMS value ($52{\pm}9{\mu}m$) of the model produced by the 3D printing method. CONCLUSION. The accuracy of the 3D printing method is superior to that of the milling method, but at present, both methods are limited in their application as a work model for prosthesis manufacture.

Computer-aided approach of parameters influencing concrete service life and field validation

  • Papadakis, V.G.;Efstathiou, M.P.;Apostolopoulos, C.A.
    • Computers and Concrete
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    • 제4권1호
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    • pp.1-18
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    • 2007
  • Over the past decades, an enormous amount of effort has been expended in laboratory and field studies on concrete durability estimation. The results of this research are still either widely scattered in the journal literature or mentioned briefly in the standard textbooks. Moreover, the theoretical approaches of deterioration mechanisms with a predictive character are limited to some complicated mathematical models not widespread in practice. A significant step forward could be the development of appropriate software for computer-based estimation of concrete service life, including reliable mathematical models and adequate experimental data. In the present work, the basis for the development of a computer estimation of the concrete service life is presented. After the definition of concrete mix design and structure characteristics, as well as the consideration regarding the environmental conditions where the structure will be found, the concrete service life can be reliably predicted using fundamental mathematical models that simulate the deterioration mechanisms. The prediction is focused on the basic deterioration phenomena of reinforced concrete, such as carbonation and chloride penetration, that initiate the reinforcing bars corrosion. Aspects on concrete strength and the production cost are also considered. Field observations and data collection from existing structures are compared with predictions of service life using the above model. A first attempt to develop a database of service lives of different types of reinforced concrete structure exposed to varying environments is finally included.