• The Transactions of the Korea Information Processing Society
• /
• v.5 no.11
• /
• pp.2973-2979
• /
• 1998

As this paper is a scheduling algorithm for the synthesis of a pipelined datapath under resource constraints in high level synthesis, the proposed heuristic algorithm uses a priority function based on the collision count of resourecs. In order to schedule the pipelined datapath under resource constraints, we define the collision count and the priority function based on the collision count, a number of resource, and the mobility of operations to resolve a resource collision. The proposed algorithm supports chaining, multicycling, and structural pipelining to design the realistic hardware. The evaluation of the Performance is compared with other systems using the results of the synthesis for a 16point FIR filter and a 5th order elliptic wave filter, where in most cases, the optimal solution is obtained.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
• /
• v.9 no.2
• /
• pp.139-149
• /
• 1991

In general, Digital Elevation Models(DEM) are constructed in a grid format for this form is advantageous to capture data automatically and is easy to manipulate. But, grid DEM requires vast volumes of data to represent terrain features finely and accurately as its data is sampled in a regular space. This paper aims at constructing compact DEM by selecting the significant points from grid DEM which affect well the terrain features. For the purpose, the significant points is detected by the high-pass filtering using Laplacian operator and gradient operator. The results of this study show that the Laplacian operator is more efficient than the gradient operator in selecting the significant points for compact DEM.

• Proceedings of the Korea Institutes of Information Security and Cryptology Conference
• /
• 1992.11a
• /
• pp.211-224
• /
• 1992

컴퓨터의 이용이 대중화되면서 PC의 확대보급으로 데이타 보안의 필요성이 강조되고 있어 본 논문에서는 PC보안의 필요성을 인식하고 PC에서의 처리, 운용되는 자료들을 보호하기 위해서 패스워드 인증, 파일 속성 변경, DES암호 알고리즘을 이용한 파일 암호화 제어, 시스템 액세스 사용자 기록 등의 기능을 적용한 PC보안시스템을 설계 및 구현하였다. 특히 키 관리에 있어서는 인증을 위한 사용자_ID와 파일 암호화키를 사용자 패스워드로 재암호화 시켜 IC카드 대신 플로피 디스켓트에 저장 보관시키고 사용자 패스워드는 사용자 자신이 직접 보관하게 하는 혼용방법을 사용하였다.

• Journal of KIISE:Computer Systems and Theory
• /
• v.32 no.7
• /
• pp.359-367
• /
• 2005

This paper presents a scheduling approach for synthesizing pipelined datapaths under resource constraints. The proposed approach evaluates whether or not a scheduling solution can exist in case an operation temporarily is assigned to the earliest or latest control step among the assignable steps for the operation. If a solution cannot be found, it is impossible to assign the operation to that control step due to a violation against resource constraints, and so we can eliminate that control step among candidate assignable control steps. The proposed algorithm builds up a schedule based on gradual mobility reduction and finds a solution that yields high performance by evaluating on the impact on register assignment. Experiments on benchmarks show that this approach gains a considerable improvement over previous approaches.

• 정보화사회
• /
• s.189
• /
• pp.36-37
• /
• 2007

포스데이타는 세계적인 철강기업인 포스코 계열의 정보기술 전문기업으로 지난 1989년에 설립됐다. 보통 그룹이나 대기업의 IT서비스 계열사들이 모기업에 의존해 시스템 구축이나 유지보수 등을 통해 성장했듯이 포스데이타도 포스코를 비롯해 계열사들의 사업을 바탕으로 성장해왔다. 하지만 포스데이타는 최근 주력 사업인 시스템통합(SI)과 아웃소싱외에 와이브로, 하이패스와 같은 신성장 사업의 육성을 통해 한 단계 도약을 노리고 있다.

• Journal of KIISE:Information Networking
• /
• v.30 no.1
• /
• pp.75-81
• /
• 2003

User authentication, including confidentiality, integrity over untrusted networks, is an important part of security for systems that allow remote access. Using human-memorable Password for remote user authentication is not easy due to the low entropy of the password, which constrained by the memory of the user. This paper presents a new password authentication and key agreement protocol suitable for authenticating users and exchanging keys over an insecure channel. The new protocol resists the dictionary attack and offers perfect forward secrecy, which means that revealing the password to an attacher does not help him obtain the session keys of past sessions against future compromises. Additionally user passwords are stored in a form that is not plaintext-equivalent to the password itself, so an attacker who captures the password database cannot use it directly to compromise security and gain immediate access to the server. It does not have to resort to a PKI or trusted third party such as a key server or arbitrator So no keys and certificates stored on the users computer. Further desirable properties are to minimize setup time by keeping the number of flows and the computation time. This is very useful in application which secure password authentication is required such as home banking through web, SSL, SET, IPSEC, telnet, ftp, and user mobile situation.

• Journal of the Korean Institute of Telematics and Electronics A
• /
• v.29A no.4
• /
• pp.74-82
• /
• 1992

This paper deals with the scheduling problems, which are the most important subtask in High-level Synthesis. ILP(integer linear programming) formulations are used as a scheduling problem approach.For practical application to digital system design, we have concentrated our attentions on pipelined datapath scheduling. For experiment results, we choose the 5-th order digital wave filter as a benchmark and do the schedule. Finally, we can obtain better and near-optimal scheduling results.

• Journal of KIISE:Databases
• /
• v.28 no.2
• /
• pp.153-167
• /
• 2001

다차원 온라인 분석처리(Multidimensional On-Line Analytical Processing: MOLAP)에서 집계 연산은 중요한 기본 연산이다. 기존의 MOLAP 집계 연산은 다차원 배열 구조를 기반으로 한 파일 구조에 대해서 연구되어 왔다. 이러한 파일 구조는 편중된 분포를 갖는 데이터에서는 잘 동작하지 못한다는 단점이 있다. 본 논문에서는 편중된 분포에도 잘 동작하는 다차원 파일구조를 사용한 집계 알고리즘을 제안한다. 먼저, 새로운 분리-포함 분할이라는 개념을 사용한 집계 연산 처리 모델을 제안한다. 집계 연산 처리에서 분리-포함 분할 개념을 사용하면 페이지들의 액세스 순서를 미리 알아 낼 수 있다는 특징을 가진다. 그리고, 제안한 모델에 기반하여 원-패스 버퍼 크기(one-pass buffer size)를 사용하여 집계 연산을 처리하는 원-패스 집계 알고리즘을 제안한다. 원-패스 버퍼 크기란 페이지 당 한 번의 디스크 액세스를 보장하기 위해 필요한 최소 버퍼 크기이다. 또한, 제안한 집계 연산 처리 모델 하에서 제안된 알고리즘이 최소의 원-패스 버퍼 크기를 갖는다는 것을 증명한다. 마지막으로, 많은 실험을 통하여 이론적으로 구한 원-패스 버퍼 크기가 실제 환경에서 정확히 동작함을 실험적으로 확인하였다. 리 알고리즘은 미리 알려진 페이지 액세스 순서를 이용하는 버퍼 교체 정책을 사용함으로써 최적의 원-패스 버퍼 크기를 달성한다. 제안하는 알고리즘을 여 러 집계 질의가 동시에 요청되는 다사용자 환경에서 특히 유용하다. 이는 이 알고리즘이 정규화 된 디스크 액세스 횟수를 1.0으로 유지하기 위해 반드시 필요한 크기의 버퍼만을 사용하기 때문이다.

• Journal of KIISE:Software and Applications
• /
• v.31 no.3
• /
• pp.343-352
• /
• 2004

Recently, the information processing of ever increasing bio-related data is becoming a very important issue. One of the main sources of these bio-data comes with the form of biopathways, which includes molecular transactions and processes that are part of biochemical systems. The information represented by biopathways includes various organic relations among its components. However, most of the current systems to represent biopathways have been initially developed without computer processing in mind, and hence suffer from inconsistencies and ambiguities. In this paper, we propose an improved notation, called UniPath, for clear and systematic representation of biopathways. The proposed system is designed to provide a unified representation of metabolic and regulatory pathways. We also designed and implemented a graphic editor for UniPath to draw biopathwavs map according to the proposed notation. The graphic editor is designed so that biopathway data can be easily transformed into XML format.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.12 no.3
• /
• pp.1350-1355
• /
• 2011

It is very important issues to protect many system resources using authorized client authentication in distributed client server systems. So it is not enough to prevent unauthorized opponents from attacking our systems that client authentication is performed using only the client's identifier and password. In this paper, we propose a secure authentication database modeling with two authentication keys such as a client authentication key and a server authentication key. The proposed authentication model can be used making high quality of computer security using two authentication keys during transaction processing. The two authentication keys are created by client and server, and are used in every request transaction without user's extra input. Using the proposed authentication keys, we can detect intrusion during authorized client's transaction processing because we can know intrusion immediately through comparing stored authentication keys in client server systems when hackers attack our network or computer systems.