• Journal of Korea Society of Industrial Information Systems
• /
• v.20 no.2
• /
• pp.11-18
• /
• 2015

As the communication technology and mobile devices develop, the need for the efficient and secure remote storage is required. And recently, many companies support cloud storages to meet the requirements of the customers. Especially in the business field where various companies collaborate, data sharing is an essential functionality to enhance their work performance. However, existing researches have not fully satisfied the requirement either efficiency and security. This paper suggests efficient and secure data sharing scheme for cloud storage by using secret sharing scheme. Proposed scheme can be applied to business collaborations and team projects.

• The Transactions of the Korea Information Processing Society
• /
• v.7 no.9
• /
• pp.2913-2919
• /
• 2000

It is essential to get large prime numbers in the design of asymmetric encryption algorithm. However, the pseudoprime numbers with high possibility to be primes have been generally used in the asymmetric encryption algorithms, because it is very difficult to find large deterministic prime numbers. In this paper, we propose a new method of deterministic prime number generation. The prime numbers generated by the proposed method have a 100% precise prime characteristic. They are also guaranteed reliability, security strength, and an ability of primitive element generation.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2008.10a
• /
• pp.712-715
• /
• 2008

RUPI-based robot service provides a variety of robot services guaranteeing extensibility and flexibility by communications between heterogeneous robots and servers. While providing robotic services, the guarantee of safety is essential. However, as to support a variety of capability of each node deployed in robotic services, security mechanisms that are suitable for each service must be applied. Also, efficient key management structure must be preceded. Therefore, in this paper, we propose a key management structure suitable for RUPI-based robot environment.

• Proceedings of the Korea Information Processing Society Conference
• /
• 2000.10a
• /
• pp.837-840
• /
• 2000

For secure communications in using multicast applications such as Cable-TV, It is essential for us to manage shared keys to encrypt/decrypt data through crypto algorithm as DES, which is called Group Key Management. In GKM, It is a hot issue that reduces the number of join/leave operation and subgroup key in key tree model. In this paper, we propose optimized mechanism of group key management required for providing multicast security.

• Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
• /
• 2004.11a
• /
• pp.179-184
• /
• 2004

High-resolution satellite imagery are used in various application field such as generation of DEM, orthophto, and three dimensional city model. To define the relation between image and object space, sensor modelling and generation of the epipolar image is essential processes. As the header information or physical sensor model becomes unavailable for the end users due to the national security or commercial purpose, generation of epipolar images without these information becomes one of important processes. In this study, epipolar geometry is generated and analysed by applying two generalized sensor models; parallel and parallel-perspective model Epipolar equation of the parallel model has linear property which is relatively simple; Epipolar geometry of the parallel-perspective model is non-linear. This linear property enable us to generate epipolar image efficiently.

• Journal of Korea Society of Digital Industry and Information Management
• /
• v.9 no.1
• /
• pp.87-93
• /
• 2013

MANET has the advantage of having the flexibility to build easily a network in a difficult situation that builds a wired network. But, data transmission errors by movement of nodes and eavesdropping by wireless communications have become a problem of security. Authentication service is the most essential in order to overcome these problems and operate network stably. In this paper, we propose 3-tiers authentication structure to exclude of malicious node and operate stable network through more systematic and thorough node authentication. After network is composed into a cluster, cluster head which play CA role is elected. Among these, the highest-CA is elected. The highest-CA receives certificates to cluster head and the cluster head evaluates trust value of their member nodes. Authentication technique which issues member node key is used. We compared PSS and experimented to evaluate performance of proposed scheme in this paper and efficiency of the proposed technique through experience was confirmed.

• Current Optics and Photonics
• /
• v.5 no.5
• /
• pp.506-513
• /
• 2021

An arrayed diffractive optical element design for the beam-shaping of a multi-array light source is proposed. This is an essential device for recent optical security and face recognition applications. In practice, we devise a DC noise reduction technique featuring high fabrication error tolerance regarding the multi-array light source diffractive optical elements, as a necessary part of the proposed design method. The spherical diverging illumination leads to DC-conjugate noise spreading. The main idea is tested experimentally, and the multi-array light source diffraction pattern is investigated numerically.

• Journal of Information Processing Systems
• /
• v.15 no.5
• /
• pp.1029-1035
• /
• 2019

In recent years, artificial intelligence (AI) services have become one of the most essential parts to extend human capabilities in various fields such as face recognition for security, weather prediction, and so on. Various learning algorithms for existing AI services are utilized, such as classification, regression, and deep learning, to increase accuracy and efficiency for humans. Nonetheless, these services face many challenges such as fake news spread on social media, stock selection, and volatility delay in stock prediction systems and inaccurate movie-based recommendation systems. In this paper, various algorithms are presented to mitigate these issues in different systems and services. Convolutional neural network algorithms are used for detecting fake news in Korean language with a Word-Embedded model. It is based on k-clique and data mining and increased accuracy in personalized recommendation-based services stock selection and volatility delay in stock prediction. Other algorithms like multi-level fusion processing address problems of lack of real-time database.

• Journal of the Korea Institute of Information Security & Cryptology
• /
• v.30 no.3
• /
• pp.405-415
• /
• 2020

With the increase in smartphone user, mobile forensics has become an essential element in modern digital forensic investigation. Mobile messenger data is very important data in mobile forensics because it can acquire information such as user's life pattern and mental state. In order to analyze messenger data, a decryption technique of an encrypted messenger data is required. Since most messengers provide a message deleting function, a technique for recovering deleted messages is required. WeChat Messenger, a messenger used by about 1 billion people around the world, uses IMEI (International Mobile Equipment Identity) information to encrypt data and provides message deletion function. In this paper, we propose a data decryption method in the absence of IMEI information and propose a method for recovering deleted messages using FTS (Full Text Search) database created for full-text search function of SQLite database.

• International Journal of Computer Science & Network Security
• /
• v.21 no.12
• /
• pp.1-8
• /
• 2021

In Mobile Ad-Hoc Network (MANET) Application, routing protocol is essential to ensure successful data transmission to all nodes. Ad-hoc On-demand Distance Vector (AODV) Protocol is a reactive routing protocol that is mostly used in MANET applications. However, the protocol causes Route Request (RREQ) message flooding issue due to the broadcasting method at the route request stage to find a path to a particular destination, where the RREQ will be rebroadcast if no Request Response (RREP) message is received. A scalable neighbor-based routing (SNBR) protocol was then proposed to overcome the issue. In the SNBR protocol, the RREQ message is only rebroadcast if the number of neighbor nodes less than a certain fix number, known as drop factor. However, since a network always have a dynamic characteristic with a dynamic number of neighbor nodes, the fix drop factor in SNBR protocol could not provide an optimal flooding problem solution in a low dense network environment, where the RREQ message is continuously rebroadcast RREQ message until reach the fix drop factor. To overcome this problem, a new broadcasting method as Dynamic SNBR (DSNBR) is proposed, where the drop factor is determined based on current number of neighbor nodes. This method rebroadcast the extra RREQ messages based on the determined dynamic drop factor. The performance of the proposed DSNBR is evaluated using NS2 and compared with the performance of the existing protocol; AODV and SNBR. Simulation results show that the new routing protocol reduces the routing request overhead, energy consumption, MAC Collision and enhances end-to-end delay, network coverage ratio as a result of reducing the extra route request messages.