• 한국멀티미디어학회논문지
• /
• 제17권9호
• /
• pp.1070-1075
• /
• 2014

Due to a number of illegal copied videos, many video content markets have been threatened. Since this copied videos have intercepted the profits of the content holders, content developers lose the will to generate new contents. Therefore, video copy detection approaches have been developed to protect the copyrights of video contents. However, many illegal uploader who generate copied videos used video transformations to avoid video copy detection systems. Among of the video transformations, rotation and flipping did not distorted the quality of video contents. Thus, these two video transformations were adopt to generate copied video. In order to detect rotated or flipping copy videos, rotation and flipping robust region binary pattern (RFR) recently was proposed. But, this RFR has a weakness according to rotated angles. Therefore, in order to overcome this problem, multi region binary patterns are proposed in this paper. The proposed method has the similar performance with the original RFR. But, it showed much higher efficiency for memory spaces.

• 전력전자학회:학술대회논문집
• /
• 전력전자학회 2001년도 Proceedings ICPE 01 2001 International Conference on Power Electronics
• /
• pp.75-79
• /
• 2001

This paper presents a novel version of an active voltage clamped ZVS-PWM high frequency inverter using IGBTs for electromagnetic induction eddy current-based rolling drum heating in new generation copy and printing machines in consumer business use. The operating principle of this inverter circuit and unique features are described herein. Its constant frequency duty cycle (asymmetrical PWM) controlled voltage source quasi-resonant soft switching high frequency inverter employing IGBTs is proposed, which is capable of achieving stable and efficient zero voltage soft switching commutation over a widely specified power regulation range from full power to low power. The operating performances in a steady state of this inverter is discussed and evaluated on basis of simulation and experimental results as an induction heated roller in new generation copy machine.

• 정보과학회 컴퓨팅의 실제 논문지
• /
• 제23권3호
• /
• pp.165-170
• /
• 2017

GPGPU의 높은 연산 처리 능력을 활용하여 길고 복잡한 계산을 하려는 시도가 많이 있다. GPGPU 프로그램의 특성상 host와 device 사이에 메모리 복사가 필요하다. 해당 메모리 복사 latency가 길 경우 프로그램의 성능에 많은 영향을 준다. 그래서 GPGPU를 활용한 프로그래밍은 최적화에 따른 성능 차이가 크다. 여러 개의 GPGPU 프로그램을 동시에 실행시키면 메모리 복사와 GPGPU 컴퓨팅이 중첩이 되어 메모리 복사 latency hiding 효과를 기대할 수 있다. 이 논문에서는 메모리 복사 latency hiding을 분석한다. 또 메모리 복사의 성능을 높이기 위해 pinned memory를 사용했을 경우의 제약 조건에 따른 성능 예측 모델링 및 알고리즘을 제안하고 이를 바탕으로 실행할 워크로드를 선택하면 41%의 성능 향상을 보인다.

• 인터넷정보학회논문지
• /
• 제2권3호
• /
• pp.71-79
• /
• 2001

점진적 속성 평가 알고리즘에서는 새로운 입력 트리가 기존 입력 트리와 정확히 비교되어서 새로운 트리를 구성할 때 기존 속성 트리의 어떤 서브 트리를 사용해야 하는가를 결정한다. 이 논문에서는 계층적 속성 문법의 점진적 평가를 효율적으로 하기 위해 점진적 속성 평가 알고리즘을 이용하였으며 Carle과 Pollock의 알고리즘을 분석하여 점진적 속성 평가 알고리즘으로 재구성하고, 속성 트리 dcopy의 구성요소를 새로운 속성 트리 d'copy에 적용하여 최적화된 속성 트리 d'copy의 점진적 속성 평가 알고리즘을 구성하였다. 또한 점진적 속성 평가 알고리즘을 이용하여 실제적인 입력 프로그램에서 재사용된 노드의 표현과 정의된 변수 형(type)이 어떻게 점진적인 속성 평가를 수행하는가를 나타내었다.

• 정보보호학회논문지
• /
• 제12권4호
• /
• pp.87-98
• /
• 2002

현재는 유형적인 물질의 가치보다 무형적인 정보의 가치가 중요시되고 있는 시대이다. 특히 하드웨어보다는 소프트웨어 제품이 훨씬 급성장하고 있지만 소프트웨어 불법 복제는 정보화시대의 가장 큰 역기능으로 이슈화 되어있다. 그러나 현재 상용화되고 있는 소프트웨어 불법복제방지제품(락)들은 복제방지에 대한 강도가 약하기 때문에 쉽게 락이 크랙되어 복제방지 기능을 할 수 없는 것들이 대부분이다. 논자는 [1,2,3]에서 DES 암호알고리즘을 대체 할 수 있는 112비트 키 길이를 갖는 96비트 블록 Cipher를 제안한 바 있으며, [3.4]에서 칩으로 하였다. 따라서 본 논문은 [1,2,3]에서 제안한 96비트 블록 Cipher와 복제방지에 필요한 보안모듈을 ASIC화하여 소프트웨어 복제방지를 위한 전용 보안칩을 설계 및 구현하며, 보안칩과 연동하여 동작되는 자동블록보호기법을 설계한다.

• 전자공학회논문지A
• /
• 제32A권12호
• /
• pp.1-8
• /
• 1995

In this paper, we propose an extendible copy network in a large-scale ATM switch consisting of small switch modules implementable on a single VLSI chip or a single PCB. Considering multicasting switches consist of a copy network and a routing network, there exist broadcast and group translators (BGT) which assign the destination addresses into copied cells. The BGT table can be reduced by vertical partitioning method; copied cells are translated in adjacent BGTs and each BGT table has a single destination address per connection. In addition, the distribution network routes and copies incomming cells into several groups statically which are translated into consecutive BGTs. This guarantees the integrity of cell sequences. Connection-setup time as well as the BGT table size can be reduced significantly.

• Journal of Communications and Networks
• /
• 제9권1호
• /
• pp.43-49
• /
• 2007

The implementation of client polling as a weak cache coherence mechanism has two major drawbacks: Firstly, the cache may return a stale copy if the object is changed in the origin server while the cached copy is considered valid. Secondly, the cache can invalidate a cached copy that is still valid in the server. Therefore, we propose a multilevel pre-fetching (MLP) in conjunction with the client polling to refine these drawbacks. MLP is introduced to improve the level of freshness among the cached objects. The simulation results presented in this paper show that the proposed MLP significantly minimizes the number of stale objects and reduces the invalidation messages sent out to the server, i.e., increase the cache HIT rate.

• 대한전자공학회:학술대회논문집
• /
• 대한전자공학회 2000년도 ITC-CSCC -2
• /
• pp.735-738
• /
• 2000

The most important issue in database security is correct concurrency control under the restrictive security policy. The goal of secure transaction management is to keep security and provide many concurrent users with the high availability of database. In this paper, we consider the security environment of multidatabase system with replicated data. The read-from relationship in the existed serializability is improper in security environment. So, we define new read-from relationship and propose new secure 1-copy quasi-seriailzability by utilizing this relationship and display some examples. This security environment requires both the existed local autonomy and the security autonomy as newly defined restriction. To solve covert channel problem is the most difficult issue in developing secure scheduling scheme. The proposed secure 1-copy quasi-serializability is very proper for global transactions in that this serializability not violates security autonomy and prevents covert channel between global transactions.

• 산업공학
• /
• 제13권1호
• /
• pp.133-140
• /
• 2000

As the internet dramatically grows, internet electronic commerce is being increased. But, as products distributed with ESD(Electronic Software Distribution) are in the form of electronic file, it is difficult to prohibit illegal copy of products. Therefore, new technology is needed to distinguish legal products from illegal ones. In this paper, we present the ESD's requirements, characteristics and a new dynamic license management technology to prevent illegal copy.

• KSBB Journal
• /
• 제16권5호
• /
• pp.435-441
• /
• 2001

In spite of the powerfulness for the simultaneous study of proteome expression and post-translational modification, 2-D PAGE has inevitable limitation on detect low aboundant proteins. Since many of the low abundant proteins are likely to have very important regulatiory functions in cells, separation and analysis of low copy number proteins is an important issue in proteome studies and challenge for 2-D techniques. Among various methods developed to detect low abundant proteins, electrophoretic protein prefractionation, chromatographic protein prefractionation, and subcellular fractionation are explained in this paper. Their practical strengths and weaknesses are also explained with current research trends.