• Journal of Korean Society for Geospatial Information Science
• /
• v.10 no.4 s.22
• /
• pp.51-60
• /
• 2002

As the use of GIS becomes more widespread, the quality and source of data is becoming more of a concern among users. But accuracy is a component of quality, and the positional accuracy is a component of total accuracy. If only we consider the positional accuracy, simultaneously collecting technology of location and attribute information, whether it be manually, using conventional surveying method, GPS, or remote sensing, is a practical way of insuring that location and attribute information are correctly correlated. This study analyse the positional accuracy from a view-point of user and supplier, which is the considerations that can ensure quality level and continuously maintain the road and underground utility information. The positional accuracy of road and underground utility information are considered as two categories - expected accuracy of data collection procedure, required accuracy of data usage process. And the project manager must consider the cost/benefit view of data generation in order to determine the surveying method.

• The Journal of the Korea Contents Association
• /
• v.17 no.2
• /
• pp.113-124
• /
• 2017

The existing social search has a problem that search results are not suitable for a user since it does not take into account the recency of the user profile and the interests of similar users. Therefore, studies on a social search considering a temporal attribute and the interests of other users are required. In this paper, we propose a social search scheme that takes into account the recent interests of a user by time and the interests of the most similar users. The proposed scheme analyzes the activity information of a social media user in order to take into account the recent interests of the user. And then the proposed scheme improves the satisfaction and accuracy of search results by combining the interests of similar users with the analyzed information and performing ranking, It is shown through performance evaluation that the proposed scheme outperforms the existing scheme.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.14 no.10
• /
• pp.4136-4156
• /
• 2020

Recently, data can be safely shared or stored using the infrastructure of cloud computing in various fields. However, issues such as data security and privacy affect cloud environments. Thus, a variety of security technologies are required, one of them is security technology using CP-ABE. Research into the CP-ABE scheme is currently ongoing, but the existing CP-ABE schemes can pose security threats and are inefficient. In terms of security, the CP-ABE approach should be secure against user collusion attacks and masquerade attacks. In addition, in a dynamic cloud environment where users are frequently added or removed, they must eliminate user access when they leave, and so users will not be able to access the cloud after removal. A user who has left should not be able to access the cloud with the existing attributes, secret key that had been granted. In addition, the existing CP-ABE scheme increases the size of the ciphertext according to the number of attributes specified by the data owner. This leads to inefficient use of cloud storage space and increases the amount of operations carried out by the user, which becomes excessive when the number of attributes is large. In this paper, CP-ABE access control is proposed to block access of withdrawn users in dynamic cloud environments. This proposed scheme focuses on the revocation of the attributes of the withdrawn users and the output of a ciphertext of a constant-size, and improves the efficiency of the user decryption operation through outsourcing.

• The KIPS Transactions:PartD
• /
• v.12D no.7 s.103
• /
• pp.1071-1078
• /
• 2005

Use case modeling is a widely used technique for functional requirements analysis of business system but it is difficult to identify a use cases at the right level and use case specifications are too long and confusing. It is also hard to determine a functional decomposition Phases·s of use cases. Therefore customer doesn't understand the use cases. This paper is defining concept of the Information Structure Modeling(ISM) and analyzing business system for the customer's perspective. ISM is an efficient mechanism for analyzing user requirements and for Identifying objects in a business system using Attribute Structure Diagram which is a major tool of the ISM that describes user event. This paper is also to show how the classes are classified and derived as event-asset-transaction type in ISM. It provides a user-friendly approach to visually representing business model.

• Journal of the Korea Society of Computer and Information
• /
• v.27 no.2
• /
• pp.107-114
• /
• 2022

Delegation is a powerful mechanism that allocates access rights to users to provide flexible and dynamic access control decisions. It is also particularly useful in a distributed environment. Among the representative delegation models, the RBDM0 and RDM2000 models are role delegation as the user to user delegation. However, In RBAC, the concept of inheritance of the role class is not well harmonized with the management rules of the actual corporate organization. In this paper, we propose an Adding Attributes on Permission-Based Delegation Model (ABDM) that guarantees the permanence of delegated permissions. It does not violate the separation of duty and security principle of least privilege. ABDM based on RBAC model, supports both the role to role and user to user delegation with an attribute. whenever the delegator wants the permission can be withdrawn, and A delegator can give permission to a delegatee.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.7 no.7
• /
• pp.1569-1584
• /
• 2013

Ubiquitous interaction in a pervasive environment is the main attribute of smart spaces. Pervasive systems are weaving themselves in our daily life, making it possible to collect user information invisibly, in an unobtrusive manner by known and even unknown parties. Huge number of interactions between users and pervasive devices necessitate a comprehensive trust model which unifies different trust factors like context, recommendation, and history to calculate the trust level of each party precisely. Trusted computing enables effective solutions to verify the trustworthiness of computing platforms. In this paper, we elaborate Unified Trust Model (UTM) which calculates entity's trustworthiness based on history, recommendation, context and platform integrity measurement, and formally use these factors in trustworthiness calculation. We evaluate UTM behaviour by simulating in different scenario experiments using a Trust and Reputation Models Simulator for Wireless Sensor Networks. We show that UTM offers responsive behaviour and can be used effectively in the low interaction environments.

• The KIPS Transactions:PartA
• /
• v.11A no.2
• /
• pp.149-158
• /
• 2004

XML as a standard for representing data and document structure is widely used in every area, and we have to write XML compilers which process the XML documents according to a user's intention. Because it takes time and costs to write XML compilers by hand, we need some generators that automatically generate XML compilers. In this paper, we introduce an XML compiler generator named XCC. It reads DTD and semantic rules, and it generates XML compiler and Java classes which correspond to the elements defined in the DTD.

• ETRI Journal
• /
• v.43 no.5
• /
• pp.812-824
• /
• 2021

Recently, with an increase in Internet usage, users of online social networks (OSNs) have increased. Consequently, privacy leakage has become more serious. However, few studies have investigated the difference between privacy and actual behaviors. In particular, users' desire to change their privacy status is not supported by their privacy literacy. Presenting an accurate measurement of users' privacy status can cultivate the privacy literacy of users. However, the highly interactive nature of interpersonal communication on OSNs has promoted privacy to be viewed as a communal issue. As a large number of redundant users on social networks are unrelated to the user's privacy, existing algorithms are no longer applicable. To solve this problem, we propose a structural similarity measurement method suitable for the characteristics of social networks. The proposed method excludes redundant users and combines the attribute information to measure the privacy status of users. Using this approach, users can intuitively recognize their privacy status on OSNs. Experiments using real data show that our method can effectively and accurately help users improve their privacy disclosures.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.10 no.4
• /
• pp.1892-1903
• /
• 2016

Mobile social network is becoming more and more popular with respect to the development and popularity of mobile devices and interpersonal sociality. As the amount of social data increases in a great deal and cloud computing techniques become developed, the architecture of mobile social network is evolved into cloud-based that mobile clients send data to the cloud and make data accessible from clients. The data in the cloud should be stored in a secure fashion to protect user privacy and restrict data sharing defined by users. Ciphertext-policy attribute-based encryption (CP-ABE) is currently considered to be a promising security solution for cloud-based mobile social network to encrypt the sensitive data. However, its ciphertext size and decryption time grow linearly with the attribute numbers in the access structure. In order to reduce the computing overhead held by the mobile devices, in this paper we propose a new Outsourcing decryption and Match-then-decrypt CP-ABE algorithm (OM-CP-ABE) which firstly outsources the computation-intensive bilinear pairing operations to a proxy, and secondly performs the decryption test on the attributes set matching access policy in ciphertexts. The experimental performance assessments show the security strength and efficiency of the proposed solution in terms of computation, communication, and storage. Also, our construction is proven to be replayable choosen-ciphertext attacks (RCCA) secure based on the decisional bilinear Diffie-Hellman (DBDH) assumption in the standard model.

• Journal of Digital Convergence
• /
• v.15 no.12
• /
• pp.341-347
• /
• 2017

As the amount of document data increases, the user needs summarized information to understand the document. However, existing document summary research methods rely on overly simple statistics, so there is insufficient research on multiple document summaries for ambiguity of sentences and meaningful sentence generation. In this paper, we investigate semantic connection and preprocessing process to process unnecessary information. Based on the vocabulary semantic pattern information, we propose a multi-document summarization method that enhances semantic connectivity between sentences using VAE. Using sentence word vectors, we reconstruct sentences after learning from compressed information and attribute discriminators generated as latent variables, and semantic connection processing generates a natural summary sentence. Comparing the proposed method with other document summarization methods showed a fine but improved performance, which proved that semantic sentence generation and connectivity can be increased. In the future, we will study how to extend semantic connections by experimenting with various attribute settings.