• Title/Summary/Keyword: $A^*$ search algorithm

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Digital Image Watermarking using Subband Correlation Wavelet Domain (웨이블릿 영역의 부대역 상관도를 이용한 디지털 영상 워터마킹)

  • 서영호;박진영;김동욱
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.40 no.6
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    • pp.51-60
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    • 2003
  • The watermarking is the technique that embeds or extracts the certain data without the change of the original data for the copyright protection of the multimedia contents. Watermark-embedded contents must not be distinguished by human's eye and must be robust to the various image processing and the intentional distortions. In this paper, we propose a new watermarking technique applied in the wavelet domain which has both the spatial and frequency information of a image. For both the robustness and the invisibility, the positions for embedding the watermark is selected with the multi-threshold. We search the similarity between highly correlated coefficients in the each subband and decide the mark space after verifying the significance in the specified subband. The similarity is represented by the coefficient difference between the subbands and its distribution is used in the watermark embedding and extracting. The embedded watermark can be extracted without the original image using the relationship of the subbands. By these properties the proposed watermarking algorithm has the invisibility and the robustness to the attacks such as JPEG compression and the general image processing.

A Study on LED Energy Efficiency in Buildings through Cloud-based User Authentication in IoT Network Environment (IoT 네트워크 환경에서 클라우드 기반의 사용자 인증을 통한 건물 내의 LED에너지 효율화 연구)

  • Ahn, Ye-Chan;Lee, Keun-Ho
    • Journal of Digital Convergence
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    • v.15 no.5
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    • pp.235-240
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    • 2017
  • Recently, Internet of things have been applied to various fields and are becoming common in our everyday life. Everything in our daily lives is networked, interacting with each other and giving us more useful effects. In this paper, we implemented an algorithm that can illuminate the LED lighting to the authorized person 's place in the network environment connected with the authentication device only once with the user authentication. User authentication in one building User authenticated through a single user search for the location of the user's lab stored in the database using the certified information and LED lights up to the lab where the user works. Through this, unnecessary energy is generated because people do not pass frequently.

High-speed W Address Lookup using Balanced Multi-way Trees (균형 다중 트리를 이용한 고속 IP 어드레스 검색 기법)

  • Kim, Won-Iung;Lee, Bo-Mi;Lim, Hye-Sook
    • Journal of KIISE:Information Networking
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    • v.32 no.3
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    • pp.427-432
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    • 2005
  • Packet arrival rates in internet routers have been dramatically increased due to the advance of link technologies, and hence wire-speed packet processing in Internet routers becomes more challenging. As IP address lookup is one of the most essential functions for packet processing, algorithm and architectures for efficient IP address lookup have been widely studied. In this paper, we Propose an efficient I address lookup architecture which shows yeW good Performance in search speed while requires a single small-size memory The proposed architecture is based on multi-way tree structure which performs comparisons of multiple prefixes by one memory access. Performance evaluation results show that the proposed architecture requires a 280kByte SRAM to store about 40000 prefix samples and an address lookup is achieved by 5.9 memory accesses in average.

The design and implementation of Object-based bioimage matching on a Mobile Device (모바일 장치기반의 바이오 객체 이미지 매칭 시스템 설계 및 구현)

  • Park, Chanil;Moon, Seung-jin
    • Journal of Internet Computing and Services
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    • v.20 no.6
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    • pp.1-10
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    • 2019
  • Object-based image matching algorithms have been widely used in the image processing and computer vision fields. A variety of applications based on image matching algorithms have been recently developed for object recognition, 3D modeling, video tracking, and biomedical informatics. One prominent example of image matching features is the Scale Invariant Feature Transform (SIFT) scheme. However many applications using the SIFT algorithm have implemented based on stand-alone basis, not client-server architecture. In this paper, We initially implemented based on client-server structure by using SIFT algorithms to identify and match objects in biomedical images to provide useful information to the user based on the recently released Mobile platform. The major methodological contribution of this work is leveraging the convenient user interface and ubiquitous Internet connection on Mobile device for interactive delineation, segmentation, representation, matching and retrieval of biomedical images. With these technologies, our paper showcased examples of performing reliable image matching from different views of an object in the applications of semantic image search for biomedical informatics.

Fast Intra Prediction Mode Decision for HEVC (HEVC의 고속 화면내 예측 모드 결정 기법)

  • Kim, Dong-Hyun;Kim, Jae-Gon
    • The Journal of the Korea Contents Association
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    • v.14 no.9
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    • pp.102-109
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    • 2014
  • Intra prediction in HEVC is also significantly improved from H.264/AVC with the increased prediction modes up to 35 that results in increase of the complexity cost. Hence, a fast intra mode decision algorithm is required for real-time applications. A fast intra mode decision is proposed in this paper for further complexity reduction in addition to the RMD (Rough Mode Decision) that has been adopted into the HEVC reference software, referred to as HM, for fast intra prediction. The proposed method reduces the complexity of intra mode decision by limiting the number of search modes in both steps of RMD and the final mode decision. Experimental results show that the proposed method provide about 13.2% encoding time reduction with 1.0% BD-rate increase on average over test sequences in HM 12.0.

Ant Colony System for solving the traveling Salesman Problem Considering the Overlapping Edge of Global Best Path (순회 외판원 문제를 풀기 위한 전역 최적 경로의 중복 간선을 고려한 개미 집단 시스템)

  • Lee, Seung-Gwan;Kang, Myung-Ju
    • Journal of the Korea Society of Computer and Information
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    • v.16 no.3
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    • pp.203-210
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    • 2011
  • Ant Colony System is a new meta heuristics algorithms to solve hard combinatorial optimization problems. It is a population based approach that uses exploitation of positive feedback as well as greedy search. It was first proposed for tackling the well known Traveling Salesman Problem. In this paper, we propose the searching method to consider the overlapping edge of the global best path of the previous and the current. This method is that we first determine the overlapping edge of the global best path of the previous and the current will be configured likely the optimal path. And, to enhance the pheromone for the overlapping edges increases the probability that the optimal path is configured. Finally, the performance of Best and Average-Best of proposed algorithm outperforms ACS-3-opt, ACS-Subpath and ACS-Iter algorithms.

Popularity-Based Pushing Scheme for Supporting Content Provider Mobility in Content-Centric Networking (콘텐츠 중심 네트워크에서 정보제공자의 이동성 지원을 위한 인기도 기반 푸싱 기법)

  • Woo, Taehee;Park, Heungsoon;Kwon, Taewook
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.40 no.1
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    • pp.78-87
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    • 2015
  • Content-Centric Networking(CCN) is a new networking paradigm to search for the routing information needed to find a data from the content name, unlike conventional IP networks. In CCN, the mobility management, one of the CCN challenges, is consists of consumer mobility and content provider mobility. Among both, in the case of the content provider mobility, it requires too much overhead and time to update routing information on the corresponding routers. In this paper, we propose Popularity-based Pushing CCN(PoPCoN) which considers the content popularity to support effective mobility of content provider in CCN. Our proposed algorithm shortens content download time for the consumer and reduces the network overhead during mobility as compared to the existing approaches.

A Study on the Shape-Based Motion Estimation For MCFI (MCFI 구현을 위한 형태 기반 움직임 예측에 관한 연구)

  • Park, Ju-Hyun;Kim, Young-Chul;Hong, Sung-Hoon
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.35 no.3C
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    • pp.278-286
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    • 2010
  • Motion Compensated Frame Interpolation(MCFI) has been used to reduce motion jerkiness for dynamic scenes and motion blurriness for LCD-panel display as post processing for large screen and full HD(high definition) display. Conventionally, block matching algorithms (BMA) are widely used to do motion estimation for simplicity of implementation. However, there are still several drawbacks. So in this paper, we propose a novel shape-based ME algorithm to increase accuracy and reduce ME computational cost. To increase ME accuracy, we do motion estimation based on shape of moving objects. And only moving areas are included for motion estimation to reduce computational cost. The results show that the computational cost is 25 % lower than full search BMA, while the performance is similar or is better, especially in the fast moving region.

Development of Prototype for Screening Anti-Inflammation Effects concerning p38 MAPK Signal Pathway (p38 MAPK을 이용한 항염증 효능 규명 프로토타입 개발)

  • Kim, Chul;Yae, Sang-Jun;Nam, Ky-Youb;Kim, Sang-Kyun;Jang, Hyun-Chul;Kim, Jin-Hyun;Kim, Young-Eun;Song, Mi-Young
    • Korean Journal of Oriental Medicine
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    • v.17 no.3
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    • pp.77-85
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    • 2011
  • Objectives : The purpose of this study was to develop a simulator which can analyze the anti-inflammatory effects of medical herbs based on e-cell concerning p38 MAPK signal pathway. Methods : We collected data concerning medical herbs with anti-inflammatory effects and the active compounds to provide as a fundamental databse and to validate the newly developed algorithm. At this time, we used the target database as pubmed and gathered the data by data mining tool, pathway studio. Also we have developed the web-based search system for confirming database related to anti-inflammation. We researched the mechanism of actions of proteins in p38 MAPK signal pathway when active compound has been inserted into the network. We reduced total network into TAK-MKK3-p38 and made the two types of mathematical model about active compounds' interaction. Results & Conclusion : We constructed the database which have 69 cases of medical herbs, 71 cases of active compounds, about 8,000 cases of URL(Uniform Resource Locator) related to papers and reports. We designed the ordinary differential equations for response of TAK, MKK3, p38 in e-cell's cytosol and nucleus. We used this formular as measure whether an active compound of medicinal plants which is inputted by an user would have an anti-inflammation effects. We developed the visualization program which could show the change of concentration over time.

Hardware Implementation of Past Multi-resolution Motion Estimator for MPEG-4 AVC (MPEG-4 AVC를 위한 고속 다해상도 움직임 추정기의 하드웨어 구현)

  • Lim Young-hun;Jeong Yong-jin
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.29 no.11C
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    • pp.1541-1550
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    • 2004
  • In this paper, we propose an advanced hardware architecture for fast multi-resolution motion estimation of the video coding standard MPEG-1,2 and MPEG-4 AVC. We describe the algorithm and derive hardware architecture emphasizing the importance of area for low cost and fast operation by using the shared memory, the special ram architecture, the motion vector for 4 pixel x 4 pixel, the spiral search and so on. The proposed architecture has been verified by ARM-interfaced emulation board using Excalibur Altera FPGA and also by ASIC synthesis using Samsung 0.18 m CMOS cell library. The ASIC synthesis result shows that the proposed hardware can operate at 140 MHz, processing more than 1,100 QCIF video frames or 70 4CIF video frames per second. The hardware is going to be used as a core module when implementing a complete MPEG-4 AVC video encoder ASIC for real-time multimedia application.