• Journal of Computing Science and Engineering
• /
• 제8권4호
• /
• pp.187-198
• /
• 2014

In this paper an efficient image encryption scheme based on cyclic rotations and multiple blockwise diffusions with two chaotic maps is proposed. A Sin map is used to generate round keys for the encryption/decryption process. A Pomeau-Manneville map is used to generate chaotic values for permutation, pixel value rotation and diffusion operations. The encryption scheme is composed of three stages: permutation, pixel value rotation and diffusion. The permutation stage performs four operations on the image: row shuffling, column shuffling, cyclic rotation of all the rows and cyclic rotation of all the columns. This stage reduces the correlation significantly among neighboring pixels. The second stage performs circular rotation of pixel values twice by scanning the image horizontally and vertically. The amount of rotation is based on $M{\times}N$ chaotic values. The last stage performs the diffusion four times by scanning the image in four different ways: block of $8{\times}8$ pixels, block of $16{\times}16$ pixels, principal diagonally, and secondary diagonally. Each of the above four diffusions performs the diffusion in two directions (forwards and backwards) with two previously diffused pixels and two chaotic values. This stage makes the scheme resistant to differential attacks. The security and performance of the proposed method is analyzed systematically by using the key space, entropy, statistical, differential and performance analysis. The experimental results confirm that the proposed method is computationally efficient with high security.

• 제어로봇시스템학회논문지
• /
• 제15권2호
• /
• pp.203-210
• /
• 2009

The problem of outdoor localization can be practically solved by GPS. However, GPS is not perfect and some areas of outdoor navigation should consider other solutions. This research deals with outdoor localization using an elevation map without GPS. This paper proposes a novel feature, elevation moment of inertia (EMOI), which represents the distribution of elevation as a function of distance from a robot in the elevation map. Each cell of an elevation map has its own EMOI, and outdoor localization can be performed by matching EMOIs obtained from the robot and the pre-given elevation map. The experiments and simulations show that the proposed EMOI can be usefully exploited for outdoor localization with an elevation map and this feature can be easily applied to other probabilistic approaches such as Markov localization method.

• 한국방재학회:학술대회논문집
• /
• 한국방재학회 2009년도 정기 학술발표대회
• /
• pp.94.1-94.1
• /
• 2009

• 한국생명과학회:학술대회논문집
• /
• 한국생명과학회 2003년도 제39회 학술심포지움
• /
• pp.140-140
• /
• 2003

• 대한지리학회:학술대회논문집
• /
• 대한지리학회 2005년도 춘계학술대회
• /
• pp.45-46
• /
• 2005

• 대한공간정보학회지
• /
• 제19권4호
• /
• pp.91-99
• /
• 2011

대규모 홍수가 빈발하여 홍수피해 규모가 천문학적으로 커지고 있는 현실에서 침수지역에 대한 침수흔적조사, 침수예상분석, 대피계획 수립 등 종합적인 검토 분석의 결과를 지도위에 표현하는 재해지도는 비구조적인 홍수방어 대책의 주요한 수단이 되고 있다. 특히, 태풍, 호우, 해일 등으로 인한 침수흔적을 조사하여 표시한 침수흔적도는 침수예상도, 재해정보지도 등과 유기적인 관계를 지니고 있는 방재 기본도임에도 불구하고 작성 예산 문제, 작성 시기 지연 및 침수흔적 표시 관리가 미흡하여 침수흔적도 작성이 불가능한 경우가 많다. 따라서 본 연구에서는 소방방재청에서 제시한 침수흔적도 제작 지침을 토대로 과거 홍수재해가 빈번하게 발생했던 지역을 대상으로 침수 피해정보와 3차원 정밀 지형정보(DEM)을 이용한 침수흔적도 작성을 통해 구축 정확도를 향상하는 방안을 제시하였다.

• 한국동물위생학회지
• /
• 제39권4호
• /
• pp.227-230
• /
• 2016

Mycobacterium avium subspecies paratuberculosis (MAP) causes Johne's disease (JD) in ruminants. This is the first large scale report to estimate the herd-level prevalence of antibodies against MAP by using an ELISA to detect antibodies in bulk tank milk (BTM) samples. The samples were collected from January 2011 to November 2011, from 636 herds of the dairy farms in the Gyeonggi and Chungbuk areas of Korea. The overall apparent prevalence of MAP antibody-positive herds was 8.5%, and regional prevalence were 32/440 (7.3%) and 22/196 (11.2%) of dairy farms in the Gyeonggi and Chungbuk areas, respectively. The results did not differ significantly by region. While we have determined the prevalence rate of MAP in the Gyenoggi and Chungbuk areas in this study, there is a continuing need for well-designed studies to calculate the prevalence of MAP in dairy herds based on culture and molecular findings.

• 예술인문사회 융합 멀티미디어 논문지
• /
• 제5권2호
• /
• pp.223-230
• /
• 2015

기존 지번방식의 주소체계로부터 도로명주소체계로의 변환으로 인해 공공 및 민간분야에서 도로명주소의 활용성이 점차 증가하고 있다. 따라서 도로명주소기본도 데이터의 신뢰성이 절실히 요구되며 이는 데이터의 정확도를 뜻한다. 그러나 도로명주소기본도는 작성당시 서로 다른 도면의 사용으로 인해 정확도가 떨어지므로 활용성 또한 미비한 실정이다. 이에 본 연구에서는 각 시도별 도로명주소기 본도의 구축현황을 파악하고, 도로명주소기본도의 위치정확도 오류를 분석하였다. 그 결과 지적현황측량 성과의 RMSE가 수치지형도측량 성과의 RMSE보다 낮게 나타난 것을 알 수 있었으며 향후 도로명주소기본도에 대한 개선방안 제시의 기초자료로 활용될 수 있을 것으로 판단된다.

• 한국측량학회:학술대회논문집
• /
• 한국측량학회 2006년도 춘계학술발표회 논문집
• /
• pp.411-417
• /
• 2006

As NGIS project has been implemented in 1995 and effectiveness of spatial information increased, Digital maps serve several purpose in administrative, living, and industrial fields. But, Digital maps have many differences with real world information and difficulties in application of managing urban facilities due to high update cost and long generation period. In this study, We suggest methodology to update a building layer of digital map in urban area as regenerating a building layer by detection of changed buildings in the existing digital map anf extraction using LIDAR data and Aerial images, more easier to acquire data and available to guarantee accuracy. Experimental results are expected to applied for constructing 3D urban model in a broad expensive urban area.

• 한국정밀공학회:학술대회논문집
• /
• 한국정밀공학회 2005년도 춘계학술대회 논문집
• /
• pp.499-502
• /
• 2005

A process map has been developed, which can identify the process conditions for weak mechanical bonding at the contact surface during the direct extrusion of a Cu-Ti bimetal bar. Bonding mechanism between Cu and Ti was assumed as a cold pressure welding. Then, the plastic deformation at the contact zone causes mechanical bonding and a new bonding criterion for pressure welding was developed as a function of the principal stretch ratio and normal pressure at the contact surface by analyzing micro local extrusion at the contact zone. Finite element analyses for extrusion of Cu-Ti bimetal bars were performed for various process conditions. The deformation history at the contact surface was traced and the proposed new bonding criterion was applied to predict whether the mechanical bonding at the Cu-Ti contact surface happens. Finally, a process map for the extrusion of Cu-Ti bimetal bar is suggested.