• Title/Summary/Keyword: Key sharing

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An HEVC intra encoder sharing DCT with RDO for a low complex hardware (하드웨어 복잡도를 줄이기 위한 RDO내 DCT 공유구조의 HEVC 화면내 예측부호화기)

  • Lee, Sukho;Jang, Juneyoung;Byun, Kyungjun;Eum, Nakwoong
    • Smart Media Journal
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    • v.3 no.4
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    • pp.16-21
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    • 2014
  • HEVC is the latest joint video coding standard with ITU-T SG16 WP and ISO/IEC JTC1/SC29/WG11. Its coding efficiency is about two times compared to H.264 high profile. Intra prediction has 35 directional modes including dc and planer. However an accurate mode decision on lots of modes with SSE is too costly to implement it with hardware. The key idea of this paper is a DCT shared architecture to reduce the complexity of HEVC intra encoder. It is to use same DCT block to quantize as well as to calculate SSE in RDO. The proposed intra encoder uses two step mode decision to lighten complexity with simplified RDO blocks and shares the transform resources. Its BD-rate increase is negligible at 20% on hardware aspect and the operating clock frequency is 300MHz@60fps on FHD ($1920{\times}1080$) image.

Improving the Availability of Scalable on-demand Streams by Dynamic Buffering on P2P Networks

  • Lin, Chow-Sing
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.4 no.4
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    • pp.491-508
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    • 2010
  • In peer-to-peer (P2P) on-demand streaming networks, the alleviation of server load depends on reciprocal stream sharing among peers. In general, on-demand video services enable clients to watch videos from beginning to end. As long as clients are able to buffer the initial part of the video they are watching, on-demand service can provide access to the video to the next clients who request to watch it. Therefore, the key challenge is how to keep the initial part of a video in a peer's buffer for as long as possible, and thus maximize the availability of a video for stream relay. In addition, to address the issues of delivering data on lossy network and providing scalable quality of services for clients, the adoption of multiple description coding (MDC) has been proven as a feasible resolution by much research work. In this paper, we propose a novel caching scheme for P2P on-demand streaming, called Dynamic Buffering. The proposed Dynamic Buffering relies on the feature of MDC to gradually reduce the number of cached descriptions held in a client's buffers, once the buffer is full. Preserving as many initial parts of descriptions in the buffer as possible, instead of losing them all at one time, effectively extends peers’ service time. In addition, this study proposes a description distribution balancing scheme to further improve the use of resources. Simulation experiments show that Dynamic Buffering can make efficient use of cache space, reduce server bandwidth consumption, and increase the number of peers being served.

CP-ABE Access Control that Block Access of Withdrawn Users in Dynamic Cloud

  • Hwang, Yong-Woon;Lee, Im-Yeong
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.14 no.10
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    • pp.4136-4156
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    • 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.

Design of Framework for Implementation of the New Paradigm Map (신 패러다임 맵 구현을 위한 프레임워크 설계)

  • Kim, Sun-Woo;Yang, Kwang-Ho;Park, Ki-Shik;Park, Ju-Young;Ra, In-Ho
    • The Journal of the Korea Contents Association
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    • v.15 no.3
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    • pp.32-39
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    • 2015
  • In this paper, We propose the futuristic map using variety technology of advanced ICT-based. The futuristic maps are expected to developed into a new format of user participation to express the results in various formats through the understanding and interpretation of the facts and phenomena of tangible and intangible that exist in the real world. In the future, the map is expected to be developed into form of a new paradigm map made in real time that economy, industry, the collection of information necessary for everyday life, processing, usage, analysis, distribution and sharing. In this paper, we provide a real-time personalized contents to digitize the information of the real space based on the concept of map, databases, spatial analysis and describes the key technologies that characterized by the representation of time-series data by analyzing and prediction every field macro phenomena of society, economy, culture and etc. And we establish the concepts of the 'New Paradigm Map' for future creative economy.

The Impacts of Media Richness, Media Usefulness, and Media Experience on the Leaner's Satisfaction with e-Learning Systems (이러닝시스템의 매체풍부성, 매체유용성, 매체경험이 학습자 만족에 미치는 영향)

  • Choi, Su-Jeong;Kang, Kyung-Jun;Ko, Il-Sang
    • Journal of Information Technology Applications and Management
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    • v.14 no.2
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    • pp.27-47
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    • 2007
  • In an effort to apply IT to practices of learning, universities are trying to implement e-Learning systems and expanding the extent of their usage. Nowadays, e-Learning systems are not only used for conducting web-based distance learning, but also used for supporting traditional classes education by encouraging communication and information sharing between instructors and learners or among the learners. There is relatively lack of studies on the exploitation of e-Learning systems in the traditional classes, in comparison with a distance education. Specifically, howe-Learning systems could support the traditional class and/or which benefits e-Learning systems could offer in the classes are among the important issues. In this study, we suggest that e-Learning systems would be the rich media to communicate and exchange information among people who participate in a class. We derive key variables like media richness and media experience from Media Richness Theory and from Channel Expansion Theory. Moreover, Media usefulness and Satisfaction of a learner with e-Learning system is drawn from the literature on IS success. We examine the effects of perceived media richness, media usefulness, and media experience on leaner's satisfaction with e-Learning systems. In addition, we also investigate learner's media usefulness perception which is positively related to media richness and media experience. Finally, learner's experience with e-Learning systems affects perceived media richness. Based on the results of an empirical test. we first suggest that perceived media richness with e-Learning systems contributes to increase media usefulness and satisfaction of a learner. Second, media experience is an important predictor of media richness and media usefulness perception. Consequently, the result can support Channel Expansion Theory. Finally, media usefulness perception affects learner's satisfaction with e-Learning systems.

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Comparative Study on Knowledge Protection in Public and Private Organizations (정부조직의 지식보호 - 민간기업과의 비교를 중심으로 -)

  • Lee, Hyangsoo
    • Informatization Policy
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    • v.17 no.1
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    • pp.78-101
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    • 2010
  • Unlike knowledge sharing or knowledge transfer, knowledge protection has received little attention in the literature. Knowledge protection play a very important role in keeping organization competitive. This study explores the differences in knowledge protection between public and private organizations by T-test and regression analysis. The results of this study shows that the level of knowledge protection in public organizations is lower than that in private organizations. There is even larger difference in the level of access to key knowledge from outside between the two sectors. Such difference can be explained by the unique characteristics of public sector organizations. Understanding why the level of knowledge protection differs between the public and private sector is very important. This study presents lessons and implications for management leadership.

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Database of National Species List of Korea: the taxonomical systematics platform for managing scientific names of Korean native species

  • Park, Jongsun;An, Jung-Hyun;Kim, Yongsung;Kim, Donghyun;Yang, Byeong-Gug;Kim, Taeho
    • Journal of Species Research
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    • v.9 no.3
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    • pp.233-246
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    • 2020
  • A scientific name is one of changeable terms in biology whenever additional research results of specific taxa is accumulated. The Database of the National Species List of Korea (DBNKo) was developed to manage taxonomic information of Korean species, designed to describe the changeable and complex taxonomical structure and information. A Korean Taxonomical Serial Number (KTSN) was assigned to each taxon, different from the normally used systems that the scientific name was considered as primary key to manage higher rank of taxa systematically. Common names were also treated with the KTSN, reflecting that common name is considered as one type of taxon. Additional taxonomic information (e.g., synonyms, original names, and references) was also added to the database. A web interface with an intuitive dashboard presenting taxonomic hierarchical structure is provided to experts and/or managers of the DBNKo. Currently, several biological databases are available in the National Institute of Biological Resources (NIBR) such as a specimen database, a digital library, a genetic information system, and the shared species data based on the DBNKo. The DBNKo started sharing species information with other institutions such as the Nakdonggang National Institute of Biological Resources. It is an ideal centralized species database to manage standardized information of Korean species.

Design of Heuristic Algorithm of Automatic Vehicle Delivery Support System (자동배차 지원시스템의 휴리스틱 알고리듬 설계)

  • Lee, Myeong-Ho
    • Journal of Digital Convergence
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    • v.11 no.3
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    • pp.181-187
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    • 2013
  • Moreover a new logistics concept is needed through the sharing information between suppliers and consumers, which maximizes the level of customers service and its flexibility by changing functional-oriented to process-oriented. In other words, Supply Chain Management(SCM) is now considered as a key aspect of business, which controls the flows of information, funds, and goods in the supply chain. Rationalization of transport-delivery system will be one of the most important issues on logistics management to the domestic companies. The companies need the effective delivery system. Especially in the case of delivery system from distribution centers to customers or vendors, it might take a long time to control the delivery system manually because it would be hard to apply the automatic vehicle routing algorithm effectively considering all the practical constraints. Thus this study develops a heuristic algorithm of automatic vehicle delivery support system in terms of grouping by short ranges of vehicle movement utilizing postal coordinates, which satisfies a variety of realistic constraints and reduces controlling time of manual operations.

The Future of Workplace in Vertical Cities: Hanging Gardens, Roof Terraces and Vertical Plazas

  • Reinke, Stephan C.
    • International Journal of High-Rise Buildings
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    • v.9 no.1
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    • pp.71-79
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    • 2020
  • As the workplace evolves in our vertical cities, the need for "think spaces" and the public realm to meet, create and innovate will become integral to tall buildings. These people places are designed to address the social challenges and enhance the co-working environments which are emerging in the dense urban context of our future cities. The design of sky terraces and the "spaces between" offer a greener, more humane and smarter work environment for the future. The public realm should no longer be held down, fixed to the ground plane, but rather become part and parcel of the upper levels of our workplace centers. These collective spaces in our workplace centers must provide a three dimensional matrix of connected and identifiable platforms to leverage the open and progressive future way of working. This will enable social networking and idea sharing, and create multi-dimensional, multi-level business incubators for innovation and creativity. The BCO ( British Council of Offices) has performed a landmark Wellness Matters Report which provides an exemplary roadmap for the future of the workplace. Our future vertical cities must also provide for serendipity in the workplace; a key attribute to drive the information exchange and collaboration that are proven to provide positive and progressive business outcomes. In addition to demonstrating examples of existing built work and the concept of the integrated vertical public realm, the presentation also will consider and define wellness in the workplace as a critical factor in our design strategies and our future workplace environments Hanging Gardens, Roof Terraces and the Vertical Plazas; designed for interchange, wellness, animation and collaboration.

Examination of Implicit Interactivity in Wiki-based Learning in University

  • Seo, Bong-Hyun;Kang, In-Ae;Nam, Sun-Woo
    • Proceedings of the Korean Society of Computer Information Conference
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    • 2010.07a
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    • pp.485-491
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    • 2010
  • The arrival of the Web 2.0 age, which is characterized by such key words as participation, sharing and openness, provides a learning environment in which both instructors and students can experience interactivity. In the educational area, we are particularly witnessing a growing interest in the social software like Wiki as one of the communication tools that reflects the characteristics of Web 2.0 and focuses on the interactivity with others. Based on this background, this study aims to examine into the meanings of interactivity inherent in the Wiki-based learning by studying such cases where Wiki is being used as a learning tool. For the purpose of our study, we practiced the Wiki-based learning method on the study subjects of the 17 junior students from U- University and 18 junior students from K- University during their 2009 fall semester teacher training courses. Through a comprehensive analysis of the questionnaires, interviews, Interactivity Measurement Diagram, examinations on the Wiki uses, Daily Self-reflection Records, and any other materials collected throughout the program, we could garner the following results: First, most of the students acknowledged that the use of Wiki was a useful communication means and helped promote their interactivity during their learning activities. Second, the interactivity of the Wiki-based learning was found to be more dynamic in the team-based projects or the community-based Wiki uses than in the instructor-oriented cases. Third, the Wiki-based learning is judged effective in expanding the scope of thinking and improving the learning capabilities through the collaborative knowledge-building process. The educational employment of the social software like Wiki in this web 2.0 age has great potentials for the true establishment of the learner-oriented learning environment, which has long remained at a standstill.

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