論文 - 岡崎 直宣
-
Evacuation Support System for Tsunami Disasters that Considers Shelter Congestion
Nishi H., Nabeyama K., Usuzaki S., Aburada K., Yamaba H., Katayama T., Park M., Okazaki N.
Lecture Notes in Electrical Engineering 1322 LNEE 51 - 62 2025年2月
担当区分：最終著者 掲載種別：研究論文（学術雑誌） 出版者・発行元：Lecture Notes in Electrical Engineering
When a tsunami occurs, an evacuation support system capable of providing information on evacuation routes and shelter locations would enable evacuations to be conducted more swiftly and safely. In previous research, a proposal was made for an evacuation support system using low-power, long-distance communication. However, a challenge arose when shelter locations reached full capacity, requiring information to be shared, which in turn necessitated redirection of evacuees to alternative shelters. Therefore, in this study, a method for sharing shelter congestion information at an earlier stage was developed. The method of sharing based on the remaining capacity of shelters increased evacuation completion by up to 29 evacuees in an evacuee population of 1000.
-
An Attempt to Solve Fill in the Missing Letters CAPTCHA Using Generative AI 査読あり
Yamaba H., Usuzaki S., Aburada K., Mukunoki M., Park M., Okazaki N.
Lecture Notes in Electrical Engineering 1322 LNEE 385 - 395 2025年2月
担当区分：最終著者 記述言語：英語 掲載種別：研究論文（国際会議プロシーディングス） 出版者・発行元：Lecture Notes in Electrical Engineering
This paper reports an attempt to solve the fill in the missing letters type CAPTCHA using generative AI. Many websites have adopted CAPTCHA to prevent bots and other automated programs from engaging in malicious activities such as posting comment spam. Text-based CAPTCHA is the most common and earliest form of CAPTCHA. However, as optical character recognition (OCR) technology has improved, the intensity of distortions applied to a CAPTCHA to keep it unrecognizable by OCR has also increased. This has reached a point where humans are having difficulty recognizing CAPTCHA text. The CAPTCHA proposed in the previous study asks users to spell a word by filling in some blanks. Since the number of letters displayed is minimal, it is challenging to identify the correct word. However, one or more images that can serve as hints to help users guess the answer word are also provided. It is expected that the ability to guess can distinguish between humans and computers. However, it is conceivable that generative AI, which has been advancing in recent years, can substitute for this ability. A series of experiments was carried out to evaluated the performance of the generative AI’s ability to solve the proposed CAPTCHA. First, we examined whether a well-known image recognition system could accurately identify the images used in the CAPTCHA problems. Next, we used the recognition results to have the generative AI solve the CAPTCHA problems and determined the accuracy rate. Additionally, we evaluated the performance of the generative AI itself by solving the problems using the correct identification of each image. From the experimental results, it was found that the CAPTCHA is relatively robust against attack techniques using generative AI.
-
A study of Collaborative malware detection using item response theory 査読あり
Takuro Inada, Shotaro Usuzaki, Kentaro Aburada, Hisaaki Yamaba, Tetsuro Katayama, Mirang Park, Naonobu Okazaki
Proc. The 30th International Symposium on Artificial Life and Robotics (AROB2025) 1070 - 1073 2025年1月
担当区分：最終著者 記述言語：英語 掲載種別：研究論文（国際会議プロシーディングス）
-
Introducing Generative AI into Unrealistic Image CAPTCHA for Effective Image Generation 査読あり
Kana Saiki, Hisaaki Yamaba, Shotaro Usuzaki, Kentaro Aburada, Masayuki Mukunoki, Mirang Park, Naonobu Okazaki
Proc. The 30th International Symposium on Artificial Life and Robotics (AROB2025) 1085 - 1090 2025年1月
担当区分：最終著者 記述言語：英語 掲載種別：研究論文（国際会議プロシーディングス）
-
Introduction of Feature Points in Images for Improvement of Finding Letters Type CAPTCHA Based on Neural Style Transfer 査読あり
Ramu Kiura, Hisaaki Yamaba, Shotaro Usuzaki, Kentaro Aburada, Masayuki Mukunoki, Mirang Park, Naonobu Okazaki
Proc. The 30th International Symposium on Artificial Life and Robotics (AROB2025) 1079 - 1084 2025年1月
担当区分：最終著者 記述言語：英語 掲載種別：研究論文（国際会議プロシーディングス）
-
Investigation of Detection Methods for Trojaned DNNs under Specific Conditions 査読あり
Shunya Izaki, Shotaro Usuzaki, Kentaro Aburada, Hisaaki Yamaba, Tetsuro Katayama, Mirang Park, Naonobu Okazaki
Proc. The 30th International Symposium on Artificial Life and Robotics (AROB2025) 1074 - 1078 2025年1月
担当区分：最終著者 記述言語：英語 掲載種別：研究論文（国際会議プロシーディングス）
-
Park M., Chang Z., Usuzaki S., Aburada K., Okazaki N.
Proceedings - 2024 12th International Symposium on Computing and Networking Workshops, CANDARW 2024 293 - 299 2024年11月
担当区分：最終著者 掲載種別：研究論文（国際会議プロシーディングス） 出版者・発行元：Proceedings - 2024 12th International Symposium on Computing and Networking Workshops, CANDARW 2024
In recent years, with the number of users utilizing online services increasing, there is growing demand for more secure authentication methods. Existing authentication methods such as passwords, PINs, and pattern locks, while highly operational and convenient, have issues such as vulnerability to brute force attacks and voyeuristic attacks. As a solution to these problems, gaze authentication has been proposed, where a user draws pre-defined characters or symbols with their gaze, and the features obtained from the trajectory information are used for personal identification. Gaze-based authentication is resistant to attacks such as voyeuristic attacks, thermal attacks, and smudge attacks because it is difficult for a third party to observe the authentication process. However, it also has drawbacks, such as a low authentication success rate and a long authentication time. Therefore, this study proposes a personal authentication system that combines gaze-based image selection and gaze trajectory features to address the issues of authentication rate and authentication time in gaze-based authentication. Additionally, to verify the effectiveness of the proposed system, we collected eye movement trajectory data from users using a gaze detection device, performed data preprocessing and feature extraction, and then calculated the personal authentication rate using several machine learning algorithms. We confirmed that XGBoost had the highest authentication accuracy with an F-measure of 67.5%. Furthermore, in the evaluation of anomaly detection algorithms, Isolation Forest demonstrated superior performance compared to other algorithms.
-
Proposal of Fill in the Missing Letters CAPTCHA Using Associations from Images 査読あり
Yamaba H., Mustaza M.N.F.B., Usuzaki S., Aburada K., Mukunoki M., Park M., Okazaki N.
Lecture Notes in Electrical Engineering 1114 LNEE 206 - 217 2024年1月
担当区分：最終著者 記述言語：英語 掲載種別：研究論文（国際会議プロシーディングス） 出版者・発行元：Lecture Notes in Electrical Engineering
This paper proposes a new fill in the missing letters type CAPTCHA using associations from images. Many web sites have adopted CAPTCHA to prevent bots and other automated programs from malicious activities such as posting comment spam. Text-based CAPTCHA is the most common and earliest CAPTCHA. But as optical character recognition (OCR) technology has improved, the intensity of distortions that must be applied to a CAPTCHA for it to remain unrecognizable by OCR has increased. This has reached a point where humans are having difficulty recognizing CAPTCHA text. The idea of the proposed CAPTCHA asks users to spell a word by filling some blanks. Since the number of shown letters are few, it is difficult to answer the correct word. But one or more images that can be used as hints to guess what is the answer word are also shown to the users. A series of experiments was carried out to evaluated the performance of the proposed CAPTCHA. First, a computer program was developed with various software languages for the usability evaluation. The system was used for the experiments to find the suitable parameters of the CAPTCHA such as numbers of letters that will be disclosed, position of disclosed letters. Next, security evaluation experiments were carried out using the system under the obtained parameters. The results of the experiments showed that the performance and limitation of the proposed CAPTCHA.
-
Proposal of a DDoS Attack Detection Method Using the Communication Interval 査読あり
Iwasa K., Usuzaki S., Aburada K., Yamaba H., Katayama T., Park M., Okazaki N.
Lecture Notes in Electrical Engineering 1114 LNEE 165 - 174 2024年1月
担当区分：最終著者 掲載種別：研究論文（学術雑誌） 出版者・発行元：Lecture Notes in Electrical Engineering
As the scale of Distributed Denial of Service (DDoS) attacks has been escalating in recent years, the need for real-time detection of attacks has increased. Existing intrusion detection systems (IDSs) perform detection with a fixed window size (assumed to be in hours). In previous research, attack detection was performed by preparing windows of multiple sizes, selecting the appropriate window based on the state of the data, and using features learned in advance for that window size. Although this method yielded a high DDoS attack detection rate of 98.30%, it exhibited a considerable false-positive rate of 7.37%. The proposed method measures the communication intervals of identical packets within the window, identified as attack-related in the previous survey, and classifies those packets with an average communication interval below a set threshold as attacks. The experiment resulted in a 50.2% decrease in the false-positive rate.
-
Study of an Image-Based CAPTCHA that is Resistant to Attacks Using Image Recognition Systems 査読あり
Nishikawa S., Usuzaki S., Aburada K., Yamaba H., Katayama T., Park M., Okazaki N.
Lecture Notes in Electrical Engineering 1114 LNEE 175 - 184 2023年10月
担当区分：最終著者 記述言語：英語 掲載種別：研究論文（国際会議プロシーディングス） 出版者・発行元：Lecture Notes in Electrical Engineering
In today’s digital age, image-based CAPTCHAs are increasingly vulnerable to attacks using annotation services, which tag images and classify images according to their contents, or reverse image search services. To prevent such attacks, an image-based CAPTCHA was proposed that takes advantage of the fact that humans can correctly recognize images containing many discontinuous points, while existing image recognition systems misrecognize them. However, this CAPTCHA proved susceptible to attacks using noise reduction filters. The objective of the present study is to create a CAPTCHA using images that are resistant to such filters. Images used in the new CAPTCHA were realized by increasing the proportion of lines forming discontinuous surfaces in images. Experimental results demonstrated a human recognition rate of 95.8%, with the image recognition systems successfully identifying only one image overall. Moreover, when a noise reduction filter was applied, the recognition rate was lower than those reported in previous studies.
-
Detection of Eye Misalignment Using an HMD with an Eye-tracking Capability 査読あり
Nagatomo Y., Uchida N., Ikeda T., Takatsuka K., Mukunoki M., Okazaki N.
Proceedings of International Conference on Artificial Life and Robotics 863 - 867 2023年2月
担当区分：最終著者 記述言語：英語 掲載種別：研究論文（国際会議プロシーディングス） 出版者・発行元：Proceedings of International Conference on Artificial Life and Robotics
In this study, we implemented the Cover Test, a test method for diagnosing eye misalignment using a head-mounted display with an eye-tracking capability. Specifically, we created a virtual examination environment in a VR space. The eye-tracking technique collected eye movements immediately after the covering or uncovering of the eyes. Thus, we calculated the amount of eye deviation and developed a system to determine the presence and magnitude of strabismus and heterophoria.We assessed the system in the verification experiment by examining the consistency between the judgment results provided by this system and the clinical evaluation approach with the Maddox rod. The result was that we could verify the horizontal eye movements more accurately.
-
Investigation of evacuation simulation from Tsunami considering road width in Aosima. 査読あり
Keita Nabeyama, Shotaro Usuzaki, Kentaro Aburada, Hisaaki Yamaba, Tetsuro Katayama, Naonobu Okazaki
Proc. The 28th International Symposium on Artificial Life and Robotics 2023年1月
担当区分：最終著者 記述言語：英語 掲載種別：研究論文（国際会議プロシーディングス）
-
On an improvement of hand gesture recognition for realizing a user authentication system using s-EMG. 査読あり
Soichiro Ishibashi, Hisaaki Yamaba, Kentaro Aburada, Tetsuro Katayama, Naonobu Okazaki
Proc. The 28th International Symposium on Artificial Life and Robotics 2023年1月
担当区分：最終著者 記述言語：英語 掲載種別：研究論文（国際会議プロシーディングス）
-
A study of improving the safety of defense system based on whitelist. 査読あり
Tsubasa Waki, Shotaro Usuzaki, Kentaro Aburada, Hisaaki Yamaba, Tetsuro Katayama, Naonobu Okazaki
Proc. The 28th International Symposium on Artificial Life and Robotics 2023年1月
担当区分：最終著者 記述言語：英語 掲載種別：研究論文（国際会議プロシーディングス）
-
Investigation of PIN authentication schemes resistant to video-based recording attacks. 査読あり
Ryo Masuzawa, Shotaro Usuzaki, Kentaro Aburada, Hisaaki Yamaba, Tetsuro Katayama, Mirang Park, Naonobu Okazaki
Proc. The 28th International Symposium on Artificial Life and Robotics 2023年1月
担当区分：最終著者 記述言語：英語 掲載種別：研究論文（国際会議プロシーディングス）
-
Development of an anti-peeping passcode keypad using color/shape cursors 査読あり
Ryo Masuzawa, Kentaro Aburada, Hisaaki Yamaba, Tetsuro Katayama, Naonobu Okazaki
Proc. The 27th International Symposium on Artificial Life and Robotics OS-7 1038 - 1042 2022年1月
担当区分：最終著者 記述言語：英語 掲載種別：研究論文（国際会議プロシーディングス）
-
An Attempt at Data Augmentation for Realizing User Authentication Using s-EMG Signals 査読あり
Soichiro Ishibashi, Yuya Yamamoto, Hisaaki Yamaba, Kentaro Aburada, Tetsuro Katayama, Naonobu Okazaki
Proc. The 27th International Symposium on Artificial Life and Robotics OS-7 1043 - 1046 2022年1月
担当区分：最終著者 記述言語：英語 掲載種別：研究論文（国際会議プロシーディングス）
-
Proposal and Evaluation of a Gesture Authentication Method with Peep Resistance for Smartwatches 査読あり
Mirang Park, Kentaro Aburada, Naonobu Okazaki
The 9th International Symposium on Computing and Networking (CANDAR 2021) ( PDAA3-3 ) 359 - 364 2021年11月
-
Proposal of Jawi CAPTCHA Using Digraphia Feature of the Malay Language 査読あり
Hisaaki Yamaba, Ahmad Saiful Aqmal Bin Ahmad Sohaimi, Shotaro Usuzaki, Kentaro Aburada, Masayuki Mukunoki, Mirang Park, and Naonobu Okazaki
16th International Workshop on Security (IWSEC 2021), LNCS 12835, Springer ( PDAA3-3 ) 119 - 133 2021年11月
-
Performance Evaluation of Blockchain Based Agricultural Input Voucher System 査読あり
Isakwisa Gaddy Tende, Kentaro Aburada, Hisaaki Yamaba, Tetsuro Katayama, Naonobu Okazaki
2021 IEEE 10th Global Conference on Consumer Electronics, GCCE 2021 637 - 638 2021年10月
担当区分：最終著者 記述言語：日本語 掲載種別：研究論文（国際会議プロシーディングス） 出版者・発行元：2021 IEEE 10th Global Conference on Consumer Electronics, GCCE 2021
Large portion of rural small-scale farmers in Tanzania can't afford to buy quality agricultural inputs (fertilizers and seeds), therefore the government of Tanzania provides these farmers with paper-based subsidy vouchers which allow them to buy the agricultural inputs at only half price. However, challenges like misuse of the vouchers by some government officials (stealing and favoritism in vouchers' allocation) and lack of trust (difficulty of verifying vouchers' authenticity) have resulted into low crop productivity for the farmers and loss of government funds. In our previous work, we developed agricultural input voucher system which stores and allocates digital subsidy vouchers to farmers in the Hyperledger Fabric blockchain network and we evaluated its performance based on transaction throughput and latency metrics which are important to farmers, who access the system through Short Message Service (SMS) in their mobile phones. The blockchain network's features such as hashing and digital signature prevent misuse and ensure trust of the digital vouchers. In this paper, we evaluate performance of the developed blockchain network based on resources (CPU and memory) consumption metrics which are important in planning resources during system deployment. The evaluation findings reveal that, Raft consensus protocol consumes resources more efficiently than Kafka consensus protocol.