Seunghwan Park

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Hierarchical identity-based encryption (HIBE) is an extension of identity-based encryption (IBE) where an identity of a user is organized as a hierarchical structure and a user can delegate the private key generation to another user. Providing a revocation mechanism for HIBE is highly necessary to keep a system securely. Revocable HIBE (RHIBE) is an HIBE(More)
A revocable identity-based encryption (RIBE) provides an efficient revocation method in IBE that a trusted authority periodically broadcasts an update key for nonrevoked users and a user can decrypt a ciphertext if he is not revoked in the update key. Boldyreva, Goyal, and Kumar (CCS 2008) defined RIBE and proposed an RIBE scheme that uses a tree-based(More)
Revocable hierarchical identity-based encryption (RHIBE) is an extension of HIBE that supports the revocation of user’s private keys to manage the dynamic credentials of users in a system. Many different RHIBE schemes were proposed previously, but they are not efficient in terms of the private key size and the update key size since the depth of a(More)
This paper presents about the localization technology to estimate the positions of the mobile robot that is able to navigate through the multi-floor spaces, for expanding the application ranges of the robots. For this purpose, the mobile robots can use some maps having some information about the spaces in advance. In this paper, the maps are divided into(More)
This paper has proposed a mapping system to build the RSSI-based fingerprint database for indoor localization. The mapping system has been developed practically to achieve two main objectives, fast and accurate radio-map construction. For the first aim, we implement the specially designed handheld mapping cart consisting of an odometer, a LiDAR, and a WLAN(More)
This paper presents three dimensional (3D) map building method for the intelligent vehicles based on accurate indoor localization using a mobile mapping system (MMS) that is equipped with perception sensors consist of a wheel odometer, a laser range finder (LRF), and two projected texture stereo (PTS) cameras. The environmental data measured by perception(More)
For the remote operation of the mobile robot, the human operator depends fully on the sensory information which is the partial information of the workspace of the mobile robot. It is usually very hard to fully manually operate the mobile robot in this situation. We propose the efficient guidance navigation method for improving the efficiency of the remote(More)
To improve the performance and efficiency of the tele-operation of robots, we suggest a method that links the information of objects and space. To do this, classifications for objects and space are carried out separately, and the relationship between them is analyzed to give adequate importance to objects and space. Categorization methods are suggested and(More)
Multi-robot cooperation promises increased performance and fault-tolerance in large-scale environments. To achieve the goal with these features, dynamic task allocation algorithm is required to adapt changing environment. Whereas previous researches mostly have been done for simplifying the mission and emphasizing the task allocation algorithm, this paper(More)