• Journal of KIISE:Computer Systems and Theory
• /
• v.31 no.5_6
• /
• pp.353-359
• /
• 2004

The illegal copying and redistribution of digitally-stored information is a crucial problem to distributors who electronically sell digital data. Fingerprinting scheme is a techniques which supports copyright protection to track redistributors of electronic information using cryptographic techniques. Anonymous fingerprinting schemes, differ from symmetric fingerprinting, prevent the merchant from framing a buyer by making the fingerprinted version known to the buyer only. And the scheme, differ from asymmetric fingerprinting, allows the buyer to purchase goods without revealing her identity to the merchant. In this paper, a new anonymous fingerprinting scheme based on secret sharing is introduced. The merchant finds a sold version that has been distributed, and then he is able to retrieve a buyer's identity and take her to court. And Schnorr's digital signature prevents the buyer from denying the fact he redistributed. The buyer's anonymity relies on the security of discrete logarithm and secure two-party computations.

• Journal of Information Science Theory and Practice
• /
• v.8 no.3
• /
• pp.30-46
• /
• 2020

This research aimed (1) to study and analyze the ability of current information retrieval (IR) systems based on views of information behavior (IB), and (2) to propose a conceptual framework for an IB model based on the collaboration between the system and user, with the intent of developing an IR system that can apply intelligent techniques to enhance system efficiency. The methods in this study consisted of (1) document analysis which included studying the characteristics and efficiencies of the current IR systems and studying the IB models in the digital environment, and (2) implementation of the Delphi technique through an indepth interview method with experts. The research results were presented in three main parts. First, the IB model was categorized into eight stages, different from traditional IB, in the digital environment, which can correspond to all behaviors and be applied to with an IR system. Second, insufficient functions and log file storage hinder the system from effectively understanding and accommodating user behavior in the digital environment. Last, the proposed conceptual framework illustrated that there are stages that can add intelligent techniques to the IR system based on the collaboration perspective between the user and system to boost the users' cognitive ability and make the IR system more user-friendly. Importantly, the conceptual framework for the IB model based on the collaboration perspective between the user and system for IR assisted the ability of information systems to learn, recognize, and comprehend human IB according to individual characteristics, leading to enhancement of interaction between the system and users.

• Journal of Digital Convergence
• /
• v.10 no.10
• /
• pp.465-473
• /
• 2012

The mobile devices and cloud computing technology introduced new content services such as N-Screen service. The DRM techniques have been developed to support interoperability and multi-platform for new environment of content service. Nevertheless, it is still inconvenient for the consumers to purchase a new DRM-supported device or to migrate some purchased contents into new device due to the change of the subscription of service. Therefore, in this paper, cloud-based DRM model which is referred as DRMaaS (DRM-as-a-Service) model, is proposed to allow the consumer to freely use and move some DRM-protected contents in various smart devices regardless of subscription of service.

• Journal of Digital Convergence
• /
• v.11 no.5
• /
• pp.299-305
• /
• 2013

Internet Data is hugely increased for high quality multimedia services and the related techniques is also developed rapidly. This paper is aimed to develop integrated internet data and Digital-Television receiving system with high performance and optimization, which is obtained by one-board integration with load control. It is applicable to various devices like computer, set-top box, home multimedia gateway etc. The performance is proved by evaluation test. It shows that the developed device can be TV tuner and internet AP for more robust multimedia services.

• ETRI Journal
• /
• v.40 no.3
• /
• pp.366-375
• /
• 2018

Recently, techniques involving head-mounted displays (HMDs) have attracted much attention from academia and industry owing to the increased demand for virtual reality and augmented reality applications. Because HMDs are positioned near to users' eyes, it is important to solve the accommodation-vergence conflict problem to prevent dizziness. Therefore, holography is considered ideal for implementing HMDs. However, within the Nyquist region, the accommodation effect is limited by the space-bandwidth-product of the signal, which is determined by the sampling number of spatial light modulators. In addition, information about the angular spectrum is duplicated over the Fourier domain, and it is necessary to filter out the redundancy. The size of the exit-pupil of the HMD is limited by the Nyquist sampling theory. We newly propose a holographic HMD with an expanded exit-pupil over the Nyquist region by using the time-multiplexing method, and the accommodation effect is enhanced. We realize time-multiplexing by synchronizing a high-speed digital micromirror device and a liquid-crystal shutter array. We also demonstrate the accommodation effect experimentally.

• Journal of the Institute of Electronics and Information Engineers
• /
• v.50 no.6
• /
• pp.138-144
• /
• 2013

In XRF systems, various techniques have been developed for the synthesis of pulse shapes using digital methods instead of traditional analog methods. Trapezoidal pulse shaping algorithms can be used for digital multi-channel pulse height analysis in X-ray spectrometer systems. In this paper, an efficient trapezoidal filter architecture is presented. In addition, we present a hardware-efficient peak value detection algorithm. By the proposed algorithm, peak value detection error is decreased by half compared with the conventional algorithm. The proposed Digital Pulse Processing(DPP) algorithm is designed using Verilog HDL and implemented using an FPGA on a test board. It is demonstrated that the implemented DPP board works successfully in practical XRF systems.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.12 no.5
• /
• pp.2416-2424
• /
• 2011

This study focused on the transition from modularity of a mechanical construction system to the seriality in a digital production system in architecture and arguing how digital design process affects the design of surface in the contemporary architecture and development of digital technology actively intermediate surface of architecture and expressive characteristics of media on surface. The analysis of two exhibition facilities of Herzog & de Meuron expose process of fabrication in the surface design and makes possible to implementation of the concept of code to seriality which shows images employed to reveal immediate representation of the perceptual communication with humans and architecture through the role and significance of digital design techniques.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
• /
• v.14 no.1
• /
• pp.27-38
• /
• 1996

Non-scale digital map have important role in the field of GIS and other application area which using geographical data in recently against conventional map restricted by scale and information. The main objective of this study is to develope the automated map production system for small scale map in conjuction with generalization techniques in a digital environment. We will intend to develope algorithms and programs for each generalization operators based on specific terrain feature with vector data. This study will be performed aspects related to an data model development of generalization process, focussing on priority for processing sequency with maintaining vector topology, and error analysis for generalized digital data.

• Journal of the Korean Society for Library and Information Science
• /
• v.49 no.1
• /
• pp.483-511
• /
• 2015

The efficiency and quality of the social reference sites are being challenged because a large quantity of the questions have not been answered or satisfied for quite a long time. Main goal of this study is to investigate important factors that affect the performance of question triage to relevant answerers in the context of social reference. To achieve the goal, expert finding techniques were used to construct an automated question triage approach to resolve this problem. Furthermore, important factors affecting triage decisions in digital reference were first examined, and extended them to the social reference setting by investigating important factors affecting the performance of automated question triage in the social reference setting. The study was conducted using question-answer pairs collected from Ask Metafilter. For the evaluation, logistic regression analyses were conducted to examine which factors would significantly affect the performance of predicting relevant answerers to questions. The results of the current study have important implications for research and practice in automated question triage for social reference. Furthermore, the results will offer insights into designing user-participatory digital reference systems.

• Journal of the Korean Institute of Telematics and Electronics S
• /
• v.36S no.11
• /
• pp.1-8
• /
• 1999

In this paper, new polyphase sequences and a sequence generation method are suggested. These sequences are found to have good correlation properties. Since the suggested generation method consists only of integer sums and modular techniques, sequence generation is also easy. The performance of the sequences is investigated when used in QS-CDMA systems under frequency selective, time nonselective, slow Nakagami fading channel with additive white Gaussian noise.