• Journal of the Korea Institute of Information Security & Cryptology
• /
• v.21 no.4
• /
• pp.3-10
• /
• 2011

To provide efficient keyword search on encrypted data, a public key encryption with keyword search (PEKS) was proposed by Boneh et al. A sender encrypts an e-mail and keywords with receiver's public key, respectively and uploads them on a server. Then a receiver generates a trapdoor of w with his secret key to search an e-mail related with some keyword w. However, Byun et al. showed that PEKS and some related schemes are not secure against keyword guessing attacks. In this paper, we propose a public key encryption with keyword search for restricted testability (PEKS-RT) scheme and show that our scheme is secure against keyword guessing attacks.

• The Transactions of the Korea Information Processing Society
• /
• v.5 no.6
• /
• pp.1593-1602
• /
• 1998

In this paper, a hybrid firewall system using the screening router, dual-homed gateway, screened host galeway and the application level gateway is proposed, The screened host gateway is comjXlsed of screening router, DMZ and bastion host. All external input traffics are filtered by screening router with network protrcol filtering, and transmitted to the bastion host performing application level filtering, The dual homed gateway is an internlediate equipment prohibiting direct access from external users, The application level gateway is an equipment enabling transmission using only the proxy server. External users can access only through the public servers in the DMZ, but internal users can aeee through any servers, The rule base which allows Telnet only lo the adrnilllslratol is applied to manage hosts in the DMZ According to the equipmental results, denial of access was in orderof Web. Mail FTP, and Telnet. Access to another servers except for server in DMZ were denied, Prolocol c1mials of UDP was more than that of TCP, because the many hosts broadcasted to networds using BOOTP and NETBIOS, Also, the illegal Telnet and FTP that transfer to inside network were very few.

• THE INTERNATIONAL COMMERCE & LAW REVIEW
• /
• v.38
• /
• pp.3-45
• /
• 2008

A motive and aim of enactment of UN Convention on the Use of Electronic Communication in Int'l Contracts is based on need to eliminate legal obstacles that might arise under existing int'l trade law instruments and promote int'l electronic commercial transaction. But when it is used with related articles, 14, 15, 16, 17 for offer under CISG, one of the most successful conventions which produces substantive law for the unification of int'l trade, questions of practical importance, for example possibilities of withdrawal, revocation, rejection of offer, the extent of its criteria arise from therewith. In conclusion, a effective electronic offer has to assure easily access and confirmation of trade terms besides criteria of offer under CISG. An offer can be withdrawal, if electronic message of withdrawal has entered the offeree's server before or at the same time when the offer has reached the offeree but agreement expressly or impliedly, between the parties about type, format, email address is a prerequisited. Implied consent could be presumed through prior conduct or trade usages between the parties under CISG articles 8, 9. The term "have reached" correspond to the time which is able to retrieve the electronic message of withdrawal. But without express or implied agreement between them about electronic communication of type, format, email address, an offer can be withdrawal before or at the same time when it has entered offeree's other e-mail address and confirmed by his retrieval. In case of the revocation, electronic message of the revocation is effective before the offeree's dispatching an acceptance. A prerequisite for the revocation by electronic communication is came as the above mentioned withdrawal except for concept of a time difference for reach. In case of a rejection of offer, when a rejection by electronic communication has entered the offeror's server, an offer is ended. But a prerequisite for the rejection by electronic message is same as the above mentioned withdrawal and revocation.

• Journal of Digital Convergence
• /
• v.10 no.6
• /
• pp.259-267
• /
• 2012

Internet telephony is an Internet service which supports voice telephone using VoIP technology on the IP-based Internet. It has some advantages in that voice telephone services can be accompanied with multimedia services such as video communication and messaging services. Recently, the introduction of smart phones has led to a growth in social networking services and thus, the research and development of Internet telephony has been actively progressed and has the potential to become a replacement for the telephone service that is currently being used. In this paper we designed and implemented an Internet telephony network system which is developed by using Asterisk and open source softwares. It is developed on the linux system and has some features such as VoIP telephony service between SIP phones, voice mail, and call recording. It also supports web-based functions such as SIP users and server system management that is implemented by Apache web server and PHP programs. Afterwards, this system will be applied as VoIP network base technology for small sized companies and organizations. It will paly a role for encouraging companies to use open source softwares.

• KSCI Review
• /
• v.14 no.2
• /
• pp.245-254
• /
• 2006

Web Forensics algorithm used to an extraction of technical Web Forensics data to be adopted to proof data regarding a crime cyber a computer at data of a great number of log History is an essential element. Propose Web Forensics algorithm, and design at these papers, and try to implement in a Web server system of an actual company. And make the Web dispatch Loging system configuration experiment that applied integrity regarding Web log History information or authentication regarding an information source. Design Web Forensics algorithm and the Flow which used for Web log History analyses at server of e-mail, webmail, HTTP (Web BBS, Blog etc.), FTP, Telnet and messengers (MSN, NateOn, Yahoo, DaumTouch. BuddyBuddy, MsLee, AOL, SoftMe) of a company, and implement through coding. Therefore have a purpose of these paper to will contribute in scientific technical development regarding a crime cyber a computer through Web Forensics.

• Journal of Advanced Navigation Technology
• /
• v.18 no.6
• /
• pp.555-561
• /
• 2014

Data processing service via internet help user to get the GNSS data processing result more precise and easily. Thus, online data process system is operated and developed by various research groups and national. But this service is difficult to use in domestic cadastral survey. In this study, we developed the online data processing system for a domestic cadastral survey. This is calculated coordinate using NGII CORS(SUWN) fiducially. And use PPP technique by GIPSY-OASIS. If user choose the observation data which want to calculate the coordinate, then is uploaded to GIPSY-OASIS server through FTP. After upload is complete, server automatically calculate coordinate, and send the report about result using e-mail. And it takes 2 minutes runtime on the basis of the 3 sessions. To verify the result, we used the data on SOUL, JUNJ as compared with notified-coordinate from NGII. As a result, got the difference for east-west 1.4 cm, north-south -1.0 cm, vertical 0.5 cm.

• Journal of the Korea Society of Computer and Information
• /
• v.12 no.1 s.45
• /
• pp.117-126
• /
• 2007

Web Forensics algorithm used to an extraction of technical Web Forensics data to be adopted to proof data regarding a crime cyber a computer at data of a great number of log History is an essential element. Propose Web Forensics algorithm, and design at these papers, and try to implement in a Web server system of an actual company. And make the Web dispatch Loging system configuration experiment that applied integrity regarding Web log History information or authentication regarding an information source. Design Web Forensics algorithm and the Flow which used for Web log History analyses at server of e-mail, webmail, HTTP (Web BBs. Blog etc.), FTP, Telnet and messengers (MSN, NateOn, Yahoo, DaumTouch, BuddyBuddy, MsLee, AOL, SoftMe) of a company, and implement through coding. Therefore have a purpose of these Paper to will contribute in scientific technical development regarding a crime cyber a computer through Web Forensics.

• Journal of Digital Convergence
• /
• v.12 no.8
• /
• pp.211-217
• /
• 2014

In this paper, by using geofencing technology to set the area you want to move tourists. Geofence set of tourists in the region enters the smartphone by sending e-mail or SMS alarm to display a detailed map of the area to visit assistance. When you arrive at the destination of the museum exhibits or exhibits to the NFC tag attached to each corresponding to a web server for a detailed description of the exhibits from the get-down. Multimedia content using an existing exhibits described. Media of exhibition space and the interaction between the visitors tour guide system capable was built.

• Proceedings of the Korea Association of Information Systems Conference
• /
• 1997.10a
• /
• pp.165-181
• /
• 1997

경영환경과 조직의 분사화의 정도가 증가함에 따라서 의사결정지원시스템 (Decision Support System)에 있어서도 분산화 된 시스템의 요구가 증가되고 있다. 이러한 관점에서 본 연구는 분산화 된 환경인 네트웍을 기반으로 하는 의사결정지원시스템을 대상 으로 사용자간의 정보공유와 사용자의 참여의 효과적인 관리를 위한 기능적 설계를 제시한 다. 정보의 공유는 의사결정지원시스템과 그룹의사결정지원시스템을 차별화 하는 가장 큰 특징이다. 이러한 정보의 공유는 과업을 수행하는 그룹단위(WorkGroup)로 이루어지는 것이 바람직하며, 그룹의 구성원들간의 의사소통과 정보를 저장하는 자료저장소(Data Warehouse)와 서버(Server)의 구축, 보다 사용하기 쉬운 그래픽 사용자 인터페이스 (Graphic User Interface)를 포함하는 전자우편(Electronic Mail), 의사결정에 참여한 사용자 에게 의사결정결과에 대한 구체적인 피드백(Feedback)을 제공할 수 있는 시스템의 구축과 같은 방법을 통해서 보다 효과적인 관리가 이루어질 수 있게 된다. 사용자의 관리는 의사결 정지원시스템이 효과를 결정하는데 중요한 요소의 하나로써 보다 많은 참여는 그륩시너지효 과(Group Synergy Effect)를 가능하게 한다. 또한 완전한 익명성(Anonymity)의 확보는 기존 의 물리적인 제한을 가진 의사결정실 GDSS의 불완전한 익명성을 충분히 대체할 수 있을 것이다. 의사결정과정의 지원에 있어서도 사용자에게 회의의 기록을 자동적으로 제공하는 것과 병행하여 회의 중에 자신이 기록해야 할 사항을 추가적으로 기록할 수 있는 모듈 (Module)을 제공하는 것이 보다 효과적일 것이다. 물론 이러한 모듈은 앞서 언급한 정보의 공유의 관점에서 본다면 참여자 자신의 피드백에 도움을 주며, 또한 유사한 수준의 다른 참 여자에게 있어서 문제에 대한 인식을 다른 사용자와의 비교를 통하여 일정수준으로 동질화 시킬 수 있게 된다.

• BMB Reports
• /
• v.30 no.4
• /
• pp.292-295
• /
• 1997

Exposure of seedling of rice (Oriza sativa cv.Dongin) to cold stress ($6^{circ}C$, 7day) induced differential gene expression. Differentially expressed polyadenylated RNA induced by low temperature were isolated and identified from the leaves of rice (Oriza sativa cv.Dongin) seedling by using the technique, differential display of reverse transcription through polymerase chain reaction (DDRT-PCR). Four bands of cDNAs were differentially displayed on the PAGE gel through DDRT-PCR, and among them three bands were those of overexpressed genes while one band was of an underexpressed gene One of the overexpressed cDNA was characterized. The size of the DDRT-PCR product was found to be about 200 bp. The sequence of the cloned DNA was compared with those of GenBank through a BLAST E-Mail server, and it was found to have no homologies in the nucleotide sequence with that of any known DNA: therefore, it was designated as RC101 The expression of the cold-stress induced-gene, RC101, was sustained with Northern Blot analysis by using the cloned DDRT-PCR product as a probe.