• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
• /
• v.29 no.3
• /
• pp.8-21
• /
• 2015

Technology for electric lighting has been evolving from Incandescent Lamp(IL) through Fluorescent Lamp(FL) and currently to Solid State Lighting(SSL) such as LED for more than 130 years of time. However, it took more than 100 years until the transition from IL to FL across overall society. That is because the transition is the Socio-Technical Transition(STT) which involves various social elements. This study investigated and analyzed the theories regarding STT, and applied the Multi-Level Perspective(MLP) theory to the case of electric lighting. A qualitative contents analysis was used with secondary data as research method, and the analyzed result was visualized based on the frame of MLP theory. The STT of electric lighting from IL to FL took place as the order of Technical Niche, Socio-Technical Regime and Landscape. Specifically, in Technical Niche level: Establishing Market Niche, Price-Performance Improvement, Learning Process and Support of Powerful Group took place. In Socio-Technical Regime level: Changes in Social Network, Changes in Technology and Changes in Rules. In Landscape level: Macro-Political Development, Socio-Economic Trends and Macro-Economic Trends took place in consecutive order.

• Bulletin of the Korean Space Science Society
• /
• 2008.10a
• /
• pp.31.1-31.1
• /
• 2008

While some observations in the geomagnetic tail region supported electrons could be accelerated by reconnection processes, we still need more observation data to confirm electron acceleration in this region. Because most acceleration processes accompany strong pitch angle diffusion, if the electrons were accelerated in this region, strong energetic electron precipitation should be observed near earth on aurora oval. Even though there are several low altitude satellites observing electron precipitation, intense and small scale precipitation events have not been identified successfully. In this presentation, we will show an observation of strong energetic electron precipitation that might be analyzed by relativistic electron acceleration in the confined region. This event was observed by low altitude Korean STSAT-1, where intense several hundred keV electron precipitation was seen simultaneously with 10 keV electrons during storm time. In addition, we observed large magnetic field fluctuations and an ionospheric plasma depletion with FUV aurora emissions. Our observation implies relativistic electrons can be generated in the small area where Fermi acceleration might work.

• Proceedings of the Korea Contents Association Conference
• /
• 2007.11a
• /
• pp.555-559
• /
• 2007

AMGA is a metadata catalogue service which offers access to metadata for files stored on the Grid. We evaluated the performance of AMGA and analyzed overhead in the current AMGA implementation. It had 700% poor throughput (read/insert per second) compared with the direct DB access. The biggest overhead was in managing GSI/SSL Connections, degrading throughput about 350%. We alsomeasured the throughput of load-balanced AMGA services, and it showed linear throughput improvement when we increased the number of AMGA server. In addition, we measured the throughputin the WAN environment, and it showed the number of the maximum connections that an AMGA server can handle is the most critical factor in the throughput.

• Journal of KIISE:Computing Practices and Letters
• /
• v.8 no.2
• /
• pp.231-239
• /
• 2002

This paper gives a comprehensive overview of the SSO solution design on the intranet. SSO described in this paper is based on LDAP, PKI and CA. We designed the data structure to hold many various application services by changing the attribute and DN of LDAP DB. We built LDAP DB using the employee records stored in our organization database. LDAP DB is routinely updated from the database. CA Server that depends on PKI is used to issue the certificates. SHTTP based on SSL is used to protect the data between certificate server and the intranet users.

• Journal of the Korea Computer Industry Society
• /
• v.5 no.1
• /
• pp.49-56
• /
• 2004

With the growing usage of the networks, the users in the Internet uses some kinds of web server. They confused that each web server uses the different user ID and passwords. To solve these problems, SSO (Single Sign-On) solution is introduced. We presents the modeling methods which are efficiently constructed the network management models. We constructed the intrusion detection systems and firewalls using the SSO. This architecture is efficient to manage the network usage and control. SSO solution designed on the small scale Intranet. CA server in the 550 that depends on PKI (Public Key Infrastructure) is used to issue the certificates. SHTTP based on SSL (Secure Socket Layer) is used to protect the data between certificate server and the intranet users.

• Journal of Convergence Society for SMB
• /
• v.6 no.2
• /
• pp.31-36
• /
• 2016

Sniffing attack is a passive attack which is reassembling packets to collect personal information, bank accounting number, and other important information. Sniffing attack happens in LAN and uses promiscuous mode which is opening filtering by pass all packets in LAN, attackers could catch any packets in LAN, so they can manipulate packets. They are Switch Jamming, Port mirroring, ARP Redirect, and ICMP Redirect attack. To defend these attacks, I proposed to use SSL packet encryption, reconfiguration of switching environment, DNS, and decoy method for defending all kinds of Sniffing attacks.

• The Journal of Korean Association of Computer Education
• /
• v.15 no.1
• /
• pp.73-85
• /
• 2012

Presently, Enhanced electronic financial service are offered used open network due to development of IT and financial transactions. The protocol in this environments such as SET, SSL/TLS, and so on are electronic transaction protocol to perform electronic payment securely and efficiently. However, most users still does not know accurately how to use and potential problems. It especially has key management problem about generate session key for purchase products or payment. To solve this problem, we propose proxy re-encryption based secure electronic transaction to transmit payment and order information without addition session key.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.27 no.11C
• /
• pp.1090-1096
• /
• 2002

The HTTP does not support continuity for browser-server interaction between successive visits or a user due to a stateless feature. Cookies were invented to maintain continuity and state on the Web. Because cookies are transmitted in plain and contain text-character strings encoding relevant information about the user, the attacker can easily copy and modify them for his undue profit. In this paper, we design a secure cookies scheme based on X.509 public key certificate for solving these security weakness of typical web cookies. Our secure cookies scheme provides not only mutual authentication between client and server but also confidentiality and integrity of user information. Additionally, we implement our secure cookies scheme and compare it to the performance with SSL(Secure Socket Layer) protocol that is widely used for security of HTTP environment.

• Bulletin of the Korean Space Science Society
• /
• 2009.10a
• /
• pp.43.2-43.2
• /
• 2009

Electron microbursts are the intense electron precipitation which durations are less than one second. We measured the energy spectra of the microbursts from 170 keV to 340 keV with solid state detectors aboard the low-altitude (680km), polar-orbiting Korean STSAT-1 (Science and Technology SATellite). The data showed that the loss cone at these energies is empty except when microbursts abruptly appear and fill the loss cone in less than 50 msec. This fast loss cone filling requires pitch angle diffusion coefficients larger than ~ 10-2rad2/sec, while ~10-5 rad2/sec was proposed by a wave particle interaction theory. We recalculated the diffusion coefficient, and reviewed of electron microburst generation mechanism with test particle simulations. This simulation successfully explained how chorus waves make pitch angle diffusion within such short period. From considering the resonance condition between wave and electrons, we also showed ~ 100 keV electrons could be easily aligned to the magnetic field, while ~ 1MeV electrons filled loss cone partially. This consideration explained why precipitating microbursts have lower e-folding energy than that of quasi-trapped electrons, and supports the theory that relativistic electron microbursts that have been observed by satellite in-situ measurement have same origin with ~100 keV electron microbursts that have been usually observed by balloon experiments.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.40 no.5
• /
• pp.815-825
• /
• 2015

DNP3(Distributed Network Protocol) is one of the most representative protocols which is used in SCADA(Supervisory Control and Data Acquisition) system. IEC 62351 is listing the integrity, confidentiality, availability and non-repudiation or accountability as the security requirement. However, IEEE Std. 1815 that is DNP3 standards does not define a mechanism for non-repudiation or accountability. In this paper, we propose a non-repudiation of origin technique about the sender of critical ASDU and implement the proposed scheme using software such as OpenSSL and SCADA source code library.