• Proceedings of the Korean Information Science Society Conference
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• 2000.04a
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• pp.418-420
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• 2000

본 연구에서는 인터넷상에 존재하는 웹 사이트를 새로운 도메인 네임으로 연결시켜주는 URL forwarding 서버를 설계 및 구현하였다. URL forwarding 서버는 수많은 인터넷 사용자들의 웹 사이트를 간단하고 다양한 형태의 URL로 매핑 시켜준다. URL forwarding 서버는 HTTP 프로토콜에서 redirection 응답코드를 기반으로 구현되었으며 Linux 시스템에서 실험을 하였다. 본 논문에서는 HTTP와 forwarding 서버를 서로 비교 분석하여 고찰해보고 구현된 forwarding 서버의 동작에 대해서 알아본다.

• Proceedings of the Korean Information Science Society Conference
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• 2004.10c
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• pp.259-261
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• 2004

무선 애드 혹 네트워크에서 이동 단말기 각각의 연결에 필요한 최소 전송 전력을 구하는 기법의 경우, 상대방 단말기에 설정된 전송 전력을 알기 위해 별도의 통신이 필요한데 애드 혹 네트워크에서 라우팅 프로토콜을 수정해서 사용할 경우 오버헤드 없이 구현이 가능하다. 또 그것을 응용하면 최소 전송 전력을 고려하는 경로를 선택함으로써 과도한 전력 소비를 줄일 수 있다. 본 논문에서는 애드 혹 네트워크에서 대표적인 라우팅 프로토콜인 AODV를 기반으로 전송 전력 제어와 결합된 AODV 프로토콜을 제안한다.

• 한국생물공학회:학술대회논문집
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• 2000.11a
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• pp.56-59
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• 2000

Thermophilic bacterium, Bacillus stearothermophilus NUB3621, was engineered to produce ethanol from glucose by introducing cloned thermostable pyruvate decarboxylase and alcohol dehydrogenase genes. A novel promoter sequence was screened and used for the enhancement of these two enzymes. Successful redirection of metabolic flux into ethanol was obtained. In addition, gene expression profiling using Bacillus subtilis DNA microarray was analyzed to overcome the intrinsic low glucose utilization of B.stearothermophilus. Many known and unknown genes were identified to be up or down regulated under glucose-containing media.

• Proceedings of the Korea Information Processing Society Conference
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• 2004.05a
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• pp.1453-1456
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• 2004

PARO, a power-aware routing optimization mechanism, is proposed in [1] to minimize the transmission power needed to forward packets between wireless devices in ad hoc network. The mechanism works by redirecting the route to pass through one or more intermediate nodes on behalf on source-destination pairs, then reducing the end-to-end transmission power. This paper will show an extension of this model and provide an analysis of the geometrical area lying between source and destination in which the intermediate node elects to perform redirection. The duration the intermediate node stays in that area is also computed.

• 한국연소학회:학술대회논문집
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• 2004.11a
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• pp.85-90
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• 2004

We have presented characteristics of a transitional behavior from a premixed flame to a triple flame in a lifted flame according to the change of equivalence ratio. The experimental apparatus consisted of a slot burner and a contraction nozzle for a lifted flame. As concentration difference of the both side of slot burner increases, the shape of flame changed from a premixed flame to a triple flame, and the liftoff height is decreased to the minimum value and then increase again. Around this minimum point, it is confirmed a transition regime from premixed flame to triple flame. Consequently, the experimental results of the liftoff height, flame curvature and luminescence intensity showed that the stabilized laminar lifted flame regime is categorized by regimes of premixed flame, triple flame and critical flame. In the visualization experiment of smoke wire, the flow divergence and redirection reappeared in premixed flame as well as triple flame. Thus we cannot express the flame front of lifted flame has a behavior of triple flame with only flow divergence and redirection. To differentiate triple flame and premixed flame, ${\Phi}$ value of partially premixed fraction is employed. The partially premixed fraction ${\Phi}$ was constant in premixed flame. In critical flame small gradient appears over the whole regime. In triple flame, typical diffusion flame shape is obtained as parabolic distribution type due to diffusion flame trailing.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.25 no.4
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• pp.873-880
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• 2015

Since hardware-based kernel-integrity monitoring systems run in the environments that are isolated from the monitored OS, attackers in the monitored OS cannot undermine the security of monitoring systems. However, because the monitoring is performed by using physical addresses, the hardware-based monitoring systems are vulnerable to Address Translation Redirection Attack (ATRA) that manipulates virtual-to-physical memory translations. To ameliorate this problem, we propose a scheduler-based ATRA detection method. The method detects ATRA during the process scheduling by leveraging the fact that kernel scheduler engages every context switch of processes. We implemented a prototype on Android emulator and TizenTV, and verified that it successfully detected ATRA without incurring any significant performance loss.

• Korea Journal of Hospital Management
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• v.8 no.1
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• pp.1-23
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• 2003

General drug prices involve three stages: shipment stage, wholesaler stage and retail stage. Policies on drug price differ from country to country. Shipment stage prices are tightly regulated in countries like France and Netherlands. They are free in only a minority of advanced countries, even if these include some major players such as the US, Germany and, in a very limited sense, Japan. The situation in the UK is very complex with a semi-free system, where drug companies are free to set their own prices but cannot exceed a predetermined profit ceiling. Mark-up at both wholesaler and retail stages is formally admitted in most countries observed. Apart from the general drug prices, reimbursement price of insured drugs has been major policy concerns. Most countries reviewed in this study has exerted some control over reimbursement prices, but differ both in the way how and in the extent to which prices are admitted or fixed. Price fixing has been used in France and Japan. Some countries have transformed their system over time, particularly to move to reference pricing in the last decade. This mechanism has empowered the customer, and improved price competition on the market. Referring to the drug price policies in the advanced countries, this study makes some suggestions for the redirection of Korean price policy for reimbursement drug in health insurance as follows: to match appropriate policy tools to each policy goal; to maximize market mechanism through effective reimbursement price fixing which admits mark-ups in wholesaler and retail prices; to introduce reference pricing system in order to redirect patient's demand with a financial incentive to choose the best-priced drugs and to save the finance of health insurance; and to strengthen surveillance and monitoring mechanism in the drug market.

• Journal of KIISE:Information Networking
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• v.32 no.6
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• pp.705-715
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• 2005

A peer-to-peer web caching has been studied recently as it can reduce the traffic converged on the server side and can support the traditional web caching model. Although the peer-to-peer web caching has the merit of having additional cache space from the local caches of peers without additional infrastructure, several constraints such as dynamic participation and local caching strategy caused by the autonomy of peers in peer-to-peer networks nay limit the performance of the peer-to-peer web caching. To overcome these limitations, we propose an efficient directory-based peer-to-peer web caching system under dynamic participation of peers. In the proposed caching system, we present new peer selection and replica management schemes by introducing the concept of the object lifetime in P2P networks. We evaluate the effectiveness of the proposed system through trace-driven simulations with a web log dataset. Simulation results show that the proposed system has higher accuracy and fewer redirection failures than the conventional directory-based P2P web caching system in feasible peer-to-peer networks.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.26 no.5
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• pp.1151-1160
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• 2016

A TrustZone-based rootkit detecting solution using a secure timer ensures the integrity of monitoring system, because ARM TrustZone technology provides isolated environments from a monitored OS against intercepting and modifying invoke commands. However, it is vulnerable to transient attack due to periodic monitoring. Also, Address Translation Redirection Attack (ATRA) cannot be detected, because the monitoring is operated by using the physical address of memory. To ameliorate this problem, we propose a snoop-based kernel introspection system. The proposed system can monitor a kernel memory in real-time by using a snooper, and detect memory-bound ATRA by introspecting kernel pages every context switch of processes. Experimental results show that the proposed system successfully protects the kernel memory without incurring any significant performance penalty in run-time.

• Convergence Security Journal
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• v.23 no.3
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• pp.29-36
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• 2023

With the recent surge in exposure to fake advertising phishing sites in search engines, the damage caused by poor search quality and personal information leakage is increasing. In particular, the seriousness of the problem is worsening faster as the possibility of automating the creation of advertising phishing sites through tools such as ChatGPT increases. In this paper, the source code of fake advertising phishing sites was statically analyzed to derive structural commonalities, and among them, a detection crawler that filters sites step by step based on foreign domains and redirection was developed to confirm that fake advertising posts were finally detected. In addition, we demonstrate the need for new guide lines by verifying that the redirection page of fake advertising sites is divided into three types and returns different sites according to each situation. Furthermore, we propose new detection guidelines for fake advertising phishing sites that cannot be detected by existing detection methods.