• Tribology and Lubricants
• /
• v.32 no.6
• /
• pp.201-206
• /
• 2016

In this study, we attempt to produce a semi-elliptical riblet with a shark skin-like surface using wire electrical discharge machining (WEDM) and micro molding techniques. Our design for the production of the semi-elliptical mold includes an electrode, a winding roller, and a guide on the WEDM system. A replication mold with negative riblets is machined using WEDM, and a shark skin inspired surface with positive riblets is fabricated using a micro molding technique. For a comparison with the original shark skin, a shark skin replica is also produced using the micro molding technique directly from a shark skin template. Droplet contact angles on a flat surface, the shark skin replica, and the epoxy resin-based micro riblet shark skin-like surface are evaluated. The effect of a Teflon coating on the contact angles for the three different surfaces is also investigated. The results show the micro riblet with a shark skin-like surface has a similar contact angle as the shark skin replica, which means that the simplified riblet shark skin surface strongly influences the performance of wettability. This study confirms the effectiveness of using the WEDM method to prepare hydrophobic surfaces with diverse surface patterns.

• Proceedings of the Korea Information Processing Society Conference
• /
• 2017.11a
• /
• pp.259-262
• /
• 2017

오픈소스 기반의 패킷 탐지 도구인 WireShark를 활용하여, 패킷을 직접 캡쳐, 분석해보고 칼리 리눅스를 활용한 시나리오 기반의 모의해킹을 시도, Snort와 Suricata를 이용하여 공격적인 성향의 패킷을 탐지하여 로그를 데이터베이스화 시킨 후 사용자 편의에 맞도록 가시화(可視化)한다. 사용자는 가시화 된 로그를 통해 공격을 좀 더 빠르게 인지하여 대응하는 것이 가능하다.

• Journal of the Korea Convergence Society
• /
• v.8 no.2
• /
• pp.15-20
• /
• 2017

In this paper, Esp8266, Node.js, and TCP / IP socket communication are used to design a compact data integration device. This device is designed to configure server and client using Esp8266 module that supports Wifi connection and to support bidirectional data transmission using TCP / IP socket communication. The server is configured using the Node.js operating system, and the database is integrated using Mysql. The network is designed to have a separate IP address by assigning a private IP address to the router, such as a home network. This device can transmit data bidirectionally, store individual client data on the server side, and can check the flow of data transmitted bidirectionally through wire-shark, so that it can be used as a compact real-time data integration and convergence device.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2013.10a
• /
• pp.653-656
• /
• 2013

TFTP(Trivial File Transfer Protocol)는 UDP(User Datagram Protocol) 기반의 파일 전송 프로토콜이다. TFTP는 프로토콜 구조가 단순하여 작은 크기의 데이터를 빠른 속도로 전송할 때 사용된다. 하지만 TFTP는 보안 기능을 지원하지 않기 때문에 데이터 노출의 위험이 있다. 본 논문에서는 Diffie-Hellman 키 교환 방식과 AES-CBC(Advanced Encryption Standard-Cipher Block Chaining) 암호화 방식을 이용하여 TFTP 프로토콜에 보안 기능을 추가하였다. Diffie-Hellman 키 교환 방식을 이용하여 두 사용자 간에 비밀 키를 공유하도록 하였고, AES-CBC 암호화를 지원하여 기밀성을 제공하도록 하였다. 수신된 데이터는 암호화 과정의 역으로 복호화를 수행하였다. WireShark 프로그램을 통하여 암호화된 데이터가 전송 되는 것을 확인하였다.

• Proceedings of the Korean Society of Computer Information Conference
• /
• 2011.06a
• /
• pp.95-99
• /
• 2011

최근 무료 WiFi Zone이 확대되고 있고, Smart Phone으로 무료 WiFi에 접속하여 인터넷으로 접속하여 메신저를 하거나, 메일확인, 정보검색 등을 한다. 하지만 무료 WiFi Zone에서 Smart Phone으로 인터넷을 할 때, 개인정보를 해킹 당 할 수가 있다. 본 논문에서 안드로이드 O,S, Smart Phone에서 무료 WiFi를 이용하여 접속한다. 먼저 메신저와 웹사이트 로그인을 한다. 이때 AirPcap을 이용하여 패킷을 캡처한다. Packet 분석 툴인 WireShark를 사용하여 Packet의 내용을 분석하고, ID, PW와 메신저 대화 내용을 해킹한다. 해킹한 개인정보 ID, 비밀번호를 이용하여 인터넷 사이트에 접속을 하여 관리자 권한을 획득한다. 그리고 Smart Phone에서 WiFi접속 시 공격에 대한 보안대책을 제시한다. 본 연구는 Smart Phone에서 무료 WiFi 접속 때, 보안성 강화연구와 무선 해킹과 방어 기술 발전에 초석이 될 것이다.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.13 no.3
• /
• pp.1583-1598
• /
• 2019

Recently, software has increased in complexity and been applied in various industrial fields. As a result, the presence of software bugs cannot be avoided. Various bug severity prediction methodologies have been proposed, but their performance needs to be further improved. In this study, we propose a novel technique for bug severity prediction in cross projects such as Eclipse, Mozilla, WireShark, and Xamarin by using topic modeling and similarity (i.e., KL-divergence). First, we construct topic models from bug repositories in cross projects using Latent Dirichlet Allocation (LDA). Then, we find topics in each project that contain the most numerous similar bug reports by using a new bug report. Next, we extract the bug reports belonging to the selected topics and input them to a Naïve Bayes Multinomial (NBM) algorithm. Finally, we predict the bug severity in the new bug report. In order to evaluate the performance of our approach and to verify the difference between cross projects and single project, we compare it with the Naïve Bayes Multinomial approach; the Lamkanfi methodology, which is a well-known bug severity prediction approach; and an emotional similarity-based bug severity prediction approach. Our approach exhibits a better performance than the compared methods.

• KNOM Review
• /
• v.24 no.2
• /
• pp.48-55
• /
• 2021

Ethereum is an open software platform based on blockchain technology that enables the construction and distribution of distributed applications. Ethereum uses a fully distributed connection method in which all participating nodes participate in the network with equal authority and rights. Ethereum networks use Kademlia-based node discovery protocols to retrieve and store node information. Ethereum is striving to stabilize the entire network topology by implementing node discovery protocols, but systems for monitoring are insufficient. This paper develops a WireShark dissector that can receive packet information in the Ethereum node discovery process and provides network packet measurement results. It can be used as basic data for the research on network performance improvement and vulnerability by analyzing the Ethereum node discovery process.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2010.10a
• /
• pp.229-232
• /
• 2010

Smart Phone is the increasing use. Smart Phone can be run on that New or videos you want to connect to the Internet for downloading and viewing applications. But the wireless Internet have been found that Due to the vulnerability of the Internet, Smart Phone security vulnerabilities. This paper analyzes the vulnerability. Smart Phone droid that occur when connecting to the Internet. For information on Smart Phone to use to analyze network packet analysis and packet capture tools. Analysis is based on information from the Internet when you use Smart Phone Hack will demonstrate the process. Messenger, ID, to confirm the password, the actual internet ID, password access to the personal information that can be seized. In this study, hacking and security of the Smart Phone will contribute to the research process that Internet information and communication powers to strengthen the security of Korea.