• Journal of the Korean Society for Aviation and Aeronautics
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• v.14 no.3
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• pp.7-15
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• 2006

Aerodynamic analysis of an airfoil in the transonic region was automated in order to enable parametric study by using the journal file of the commercial analysis code FLUENT, pre/post process Gambit and computational mathematics code MATLAB. The automated capability was illustrated via NACA 0012 and RAE 2822 airfoils. This analysis was carried out at Mach numbers ranged from 0.70 to 0.80, angles of attack; 1$^{\circ}$, 2$^{\circ}$ and 4$^{\circ}$, Reynolds numbers; 4.0${\times}$106, 6.5${\times}$106. The analysis results of a pressure coefficient were verified by comparing with the experimental data which were measured in terms of chord length because the pressure coefficient of an airfoil surface is a good estimator of flow characteristics. The results of two airfoils show that this analysis code is useful enough to be used in the design optimization of airfoil.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.13 no.1
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• pp.115-129
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• 2003

This paper presents a semi-automated formal verification method based on the famous SVO logic, and discusses its experimental results. We discuss several problems on automating the SVO logic and design its derivative, ASVO logic for automation. Also the proposed method is implemented by the Isabelle/Isar system. As a result, we verified the well-known weakness of the NSSK protocol that is vulnerable to the Denning-Sacco attack, using our Isabelle/ASVO system. Finally, we refined the protocol by following the logical consequence of the ASVO verification.

• Journal of the Korea Society of Computer and Information
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• v.12 no.1 s.45
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• pp.127-135
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• 2007

As the Internet is used widely, criminal offense that use computer is increasing, and an information security technology to remove this crime is becoming competitive power of the country. In this paper, we suggest network-based intrusion detection system that use fuzzy expert system. This system can decide quick intrusion decision from attack pattern applying fuzzy rule through the packet classification method that is done similarity of protocol and fixed time interval. Proposed system uses fuzzy logic to detect attack from network traffic, and gets analysis result that is automated through fuzzy reasoning. In present network environment that must handle mass traffic, this system can reduce time and expense of security

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.13 no.2
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• pp.978-1002
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• 2019

With the rapid development of the Internet of Things, the problem of privacy protection has been paid great attention. Recently, Nikooghadam et al. pointed out that Kumari et al.'s protocol can neither resist off-line guessing attack nor preserve user anonymity. Moreover, the authors also proposed an authentication supportive session initial protocol, claiming to resist various vulnerability attacks. Unfortunately, this paper proves that the authentication protocols of Kumari et al. and Nikooghadam et al. have neither the ability to preserve perfect forward secrecy nor the ability to resist key-compromise impersonation attack. In order to remedy such flaws in their protocols, we design a lightweight authentication protocol using elliptic curve cryptography. By way of informal security analysis, it is shown that the proposed protocol can both resist a variety of attacks and provide more security. Afterward, it is also proved that the protocol is resistant against active and passive attacks under Dolev-Yao model by means of Burrows-Abadi-Needham logic (BAN-Logic), and fulfills mutual authentication using Automated Validation of Internet Security Protocols and Applications (AVISPA) software. Subsequently, we compare the protocol with the related scheme in terms of computational complexity and security. The comparative analytics witness that the proposed protocol is more suitable for practical application scenarios.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.35 no.8
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• pp.685-692
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• 2007

This paper describes the development procedure of GUI Program for the automated generation of airfoil performance table used in helicopter comprehensive code. Considering commercialization, the program is developed based on the Windows operating system. In addition, it is aimed to enhance user's convenience by including embedded postprocessor which enables real-time display of calculation procedure and grid system. Using the validated CFD code, the aerodynamic analyses are automated for a given range of Mach number and angles of attack. The computational grid system is designed to generate automatically once the surface coordinates are given. Mixed-Language scheme is employed in order to combine the CFD code in Fortran with C++ based GUI program, which makes the time-consuming code conversion unnecessary.

• The KIPS Transactions:PartC
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• v.18C no.2
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• pp.71-78
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• 2011

Financial accidents such as password exposure of credit cards or bankbooks occur often when a password is inputted to ATM/CD(Automated Teller Machines and Cash Dispenser), so particular attention is required when inputting a password. This study suggested a method to input a password safely to prevent stealing a glance at a password in case of the use of ATM/CD. The method is that users input a password when numbers are randomly displayed and disappear not to notice the password even though someone is next to or behind the users. As methods to input a password safely, the study verified safety by dividing the methods into a test of shoulder surfing, an intuitive perspective, and a theoretical analysis. In addition, the result of implementation to apply the method to ATM/CD shows that a percentage of acquiring a password from the attack of shoulder surfing is found to be lower than an existing method, so password exposure can be prevented.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.30 no.1
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• pp.59-74
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• 2020

The web space where web applications run is the cyber information warfare of attackers and defenders due to the open HTML. In the cyber attack space, about 84% of worldwide attacks exploit vulnerabilities in web applications and software. It is very difficult to detect web vulnerability attacks with security products such as web firewalls, and high labor costs are required for security verification and assurance of web applications. Therefore, rapid vulnerability detection and response in web space by automated software is a key and effective cyber attack defense strategy. In this paper, we establish a security risk management model by intensively analyzing security threats against web applications and software, and propose a method to effectively diagnose web and application vulnerabilities. The testing results on the commercial service are analyzed to prove that our approach is more effective than the other existing methods.

• Journal of Korea Game Society
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• v.5 no.1
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• pp.41-44
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• 2005

This paper is model can be useful and capable of automatically collecting and classifying the various information about a wide range of security incidents such as hackings, worms, spyware, cyber-terror, network espionage and information warfare from firewall, IDS, VPN and so on. According to them Internet game and an automated/integrated computer emergency response system can perform an attack assessment and an early warning for any incidents based on Enterprise Security Management environment.

• International Journal of Advanced Culture Technology
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• v.10 no.3
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• pp.393-396
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• 2022

Recently, rapid climate change has had a significant impact on the ecosystem of honeybees. In addition, the problem of Vespa Hornets invasion of colonies has a fatal impact on the bee ecosystem, independent of climate change. Especially in late summer. This study relates to a method for preventing Vespa Hornets attack. In this study, we developed a Vespa Hornets sound detection device was developed by collecting and analyzing the sound of a Vespa Hornets and applying IoT technology. The developed device detects the sound of a Vespa Hornets when Vespa Hornets appears around the hive of the bees and sends a signal to automatically close the door of the beehive. The device that receives the signal drives the motor that controls the honeycomb door to close the beehive door. The Vespa Hornets sound detection device operates until no Vespa Hornets sound is detected. The system developed by us is expected to be installed in the beehives of actual beekeeping farms to dramatically reduce the damage caused by by Vespa Hornets.

• Journal of Information Processing Systems
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• v.19 no.4
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• pp.540-553
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• 2023

The hollow letter CAPTCHA (Completely Automated Public Turing test to tell Computers and Humans Apart) is an optimized version of solid CAPTCHA, specifically designed to weaken characteristic information and increase the difficulty of machine recognition. Although convolutional neural networks can solve CAPTCHA in a single step, a good attack result heavily relies on sufficient training data. To address this challenge, we propose a seed filling algorithm that converts hollow characters to solid ones after contour line restoration and applies three rounds of detection to remove noise background by eliminating noise blocks. Subsequently, we utilize a support vector machine to construct a feature vector for recognition. Security analysis and experiments show the effectiveness of this algorithm during the pre-processing stage, providing favorable conditions for subsequent recognition tasks and enhancing the accuracy of recognition for hollow CAPTCHA.