• Title/Summary/Keyword: shared space

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CP-ABE Access Control that Block Access of Withdrawn Users in Dynamic Cloud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 In this paper, CP-ABE access control is proposed to block access of withdrawn users in dynamic cloud environments. This proposed scheme focuses on the revocation of the attributes of the withdrawn users and the output of a ciphertext of a constant-size, and improves the efficiency of the user decryption operation through outsourcing.

A Study on the Improvement Direction of Natural Heritage in the Cultural Heritage Protection Act - Focused on the Landscape Architecture Field in Cultural Heritage - (문화재보호법에서 자연유산 분야의 개선 방향에 관한 연구 - 문화재 조경분야를 중심으로 -)

  • Chin, Sang-Chul
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.37 no.3
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    • pp.127-133
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    • 2019
  • This study intends to discuss the system improvement of landscape architecture field in the cultural heritage protection system, which is changing continuously. The results are as follows. First, the status of landscape architecture in cultural heritage, including natural monuments and scenic sites, must be defined. If possible, careful consideration should be given to establish the natural monuments law and scenic sites law, respectively, related to landscape architecture. Second, natural heritage must be preserved by focusing on "space" to include cultural artifacts and landscapes that may be missing through the method of "object" focused protection. Institutionally, the scope of work should be clearly shared by reviewing the redundancy and interrelationship of related laws. Third, in order to protect and manage natural heritage, a department that is wholly responsible for landscape architecture should be established independently at the Cultural Heritage Administration. Fourth, the landscape architecture field should be specified as the requirements for the commissioner of commission at the Cultural Heritage Protection Act. In addition, it is necessary to improve the system such as expending the roles of the repairing technician for landscape architecture and plants in the Cultural Heritage Protection Act.

Optimization of wire and wireless network using Global Search Algorithm (전역 탐색 알고리즘을 이용한 유무선망의 최적화)

  • 오정근;변건식
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2002.11a
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    • pp.251-254
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    • 2002
  • In the design of mobile wireless communication system, the location of BTS(Base Transciver Stations), RSC(Base Station Controllers), and MSC(Mobile Switching Center) is one of the most important parameters. Designing wireless communication system, the cost of equipment is need to be made low by combining various, complex parameters. We can solve this problem by combinatorial optimization algorithm, such as Simulated Annealing, Tabu Search, Genetic Algorithm, Random Walk Algorithm that have been extensively used for global optimization. This paper shows the four kind of algorithms which are applied to the location optimization of BTS, BSC, and MSC in designing mobile communication system and then we compare with these algorithms. And also we analyze the experimental results and shows the optimization process of these algorithms. As a the channel of a CDMA system is shared among several users, the receivers face the problem of multiple-access interference (MAI). Also, the multipath scenario leads to intersymbol interference (ISI). Both components are undesired, but unlike the additive noise process, which is usually completely unpredictable, their space-time structure helps to estimate and remove them.

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Information Acquisition of Simulation Objects by Resolution in Multi-resolution Model based War Game (다중 해상도 모델 기반 워게임 체계에서 해상도별 모의 객체의 정보 획득)

  • Bae, Hyun Shik;Rhee, Eun joo
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.22 no.1
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    • pp.147-154
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    • 2018
  • In this paper, we propose methods to acquire enemy object information, which is frequently required in multi-resolution model based war game and affects the simulation performance. In the information request method, a multi-resolution model selects information of a specific resolution and provides them to external objects. In the information announcement method, a multi-resolution model announces all information, and external objects select information of a specific resolution. In the information sharing method, external objects obtains information of a specific resolution by inquiring all information of a multi-resolution model which are stored in a shared space. Simulation results show that the information sharing method is more efficient than the information request method and the information announcement method because the information acquisition is fast. In addition, the proposed methods will increase the efficiency of war game operation by shortening the time for acquiring enemy forces' information.

A Study on the DB establishment and traceable management of the Urban transit standardization project (도시철도 표준화사업의 데이터베이스 구축 및 추적성 관리에 관한 연구)

  • Lee, Woo-Dong;Chung, Jong-Duck
    • Journal of the Korean Society for Railway
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    • v.14 no.6
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    • pp.501-506
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    • 2011
  • The study and techniques of system engineering have been applied to various fields including space-air, national defense division in advanced countries. Korea is currently in the early stages of introducing system engineering scheme in railway system and national defense division restrictedly. As theory and application of system engineering covers a wide scope, documents management and requirement analysis technology applied to establishment of standard and core unit development of the research target. The techniques which are historical management and trace among standards for establishment of standard are introduced using SE tools and participating agencies shared the information by constructing of database from all documents which are generated from the project. Through the functional analysis of the requirements for the intelligent station monitoring system in basic design stage, established requirements are verified and will be made official announcement as standard of the intelligent station monitoring system.

A Study on the Origin and Form of Pagodas in Myanmar (미얀마 불탑의 기원과 형식 유래에 대한 고찰)

  • Cheon, Deuk-Youm;Yeom, Seung Hoon
    • Journal of architectural history
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    • v.27 no.2
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    • pp.63-78
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    • 2018
  • Pagodas in Myanmar can be largely divided into Zedi and Pato. Zedi is a developed form of the early domed pagodas in India and Sri Lanka, which can be found in the introduction of Buddhism in Myanmar and the comparison of early pagodas in India, Sri Lanka and Myanmar. On the other hand, Pato is where statues of Buddha were enshrined, which is why many scholars referred to it as a temple. However, this study proposes that Pato shall be referred to as a temple-style pagoda in a form unique to Myanmar, based on the origin of Pato, definition of pagodas, and Sarira Enrichment Record of Pato. Moreover, it seems more appropriate to name this type of structure Stupa Temple(塔殿) or Stupa Shrine(塔堂) rather than a Buddhist temple(佛殿) or Buddhist shrine(佛堂) for clear distinction. Pato, or temple-style pagodas, has a ${\acute{S}}ikhara-style$ structure at the center like Ananda Pato upon entering the Pagan (Bagan) kingdom period, on which Zedi-style structures are built. As a result of examining the integration of various Buddhist schools and religions focused on Theravada during the period of King Anawrahta and King Kyanzittha, the ${\acute{S}}ikhara-style$ structure is a symbolic representation of the fact that Theravada embraced Hinduism. The common features shared by pagodas in Myanmar are the centrality of place and the verticality of $y{\check{a}}ngti{\bar{a}}n$ (looking up to the sky) in terms of shape. All temples are placed at the most important and central space, and their forms represent strong religious $y{\check{a}}ngti{\bar{a}}n$ and verticality. These are the features that stand out most among various pagodas in Buddhist countries.

Use of Housing through Oral Life History of Korean Chineses in Harbin, China - Focused on use of housing, cultural assimilation and acculturation - (생애구술을 통해 본 중국 할빈지역 조선족의 주거의 사용 - 주거의 사용과 생활문화의 동화 및 문화접변을 중심으로 -)

  • Hong, Hyung-Ock
    • Journal of Families and Better Life
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    • v.28 no.6
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    • pp.81-94
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    • 2010
  • This qualitative research was designed to explore the use of housing among Korean Chinese people in Harbin, China. Focusing on the use which based on the epistemology of housing adjustment, this was particularly designed to examine its cultural assimilation and acculturation on the way of life course, it employed the in-depth interview on the oral history of 5 interviewees in their 60s and 70s, individualized interviews were conducted from May 28 to 31 in 2010. Key findings were summarized as follows; 1. The free market reform in China resulted in privatization that allowed respondents to become homeowners, and the ownership was viewed as part of family asset centered upon a sense of solidarity. 2. Although homeowners in multi-story houses were responsible to decorate interior spaces, the common features in using interior spaces were found: entrance had no thresholds; kitchen was small, lack of storage cabinets, tile-flooring; washers were installed inside bathroom; and newly built apartment didn't have proper space to store Korean fermented foods. It was observed that housing adaptation outweighed housing adjustment. Those who used to live in Chinese houses with indoor-wearing-shoes or Russian houses with indoor-wearing-slippers were receptive to the use of dining table and bed, and the community heating system discouraged the use of individual electric water heater because of high electricity cost. 3. In daily life, eating habit wasn't much changed to the Chinese style, meals were shared, dish sterilizer was popular, and Kimchi fridge wasn't used. Because of the influence of the Chinese culture, such Korean traditions as ancestral rites and bedroom allocation tradition faded away, but traditional family values remained unchanged. In conclusion, Korean Chinese people experience normative housing deficits and adaptation selectively incurred. It's implied that residential design meets the needs resulting from the dual culture in terms of cultural assimilation and acculturation.

A Scalable Content-Sharing Architecture for High-quality TV Programs (확장 가능한 실시간 고화질 TV 컨텐츠 공유 아키텍처)

  • Chung, Sungwook
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.18 no.11
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    • pp.2651-2657
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    • 2014
  • It can be organized with PVRs and FC-AL for a high-quality TV content-sharing architecture. It is, however, not easy to configure a large community network with the FC-AL since it has a 7-bit address space with supporting up to 127 users. We, therefore, propose a novel scalable FC-AL multiple-loop architecture using shared disks, which does not need to use expensive and load-concentrated switches. In this article, our suggested architecture shows a superb startup delay, such as less than 20msec. In addition, it demonstrates outstanding scalability, such that the number of accomodable users increases almost linearly according to adding loops. Lastly, it reveals exceptional time-shifting hours, that is, which supports more than 140 hours with 1000 users.

A Performance Evaluation of Parallel Color Conversion based on the Thread Number on Multi-core Systems (멀티코어 시스템에서 쓰레드 수에 따른 병렬 색변환 성능 검증)

  • Kim, Cheong Ghil
    • Journal of Satellite, Information and Communications
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    • v.9 no.4
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    • pp.73-76
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    • 2014
  • With the increasing popularity of multi-core processors, they have been adopted even in embedded systems. Under this circumstance many multimedia applications can be parallelized on multi-core platforms because they usually require heavy computations and extensive memory accesses. This paper proposes an efficient thread-level parallel implementation for color space conversion on multi-core CPU. Thread-level parallelism has been becoming very useful parallel processing paradigm especially on shared memory computing systems. In this work, it is exploited by allocating different input pixels to each thread for concurrent loop executions. For the performance evaluation, this paper evaluate the performace improvements for color conversion on multi-core processors based on the processing speed comparison between its serial implementation and parallel ones. The results shows that thread-level parallel implementations show the overall similar ratios of performance improvements regardless of different multi-cores.

A Study on Visual Attention on Color Perception by Visitors of Children's Hospital (어린이병원 방문자의 색채지각에 나타난 시각적 주의에 관한 연구)

  • Cho, Eun-Kil;Son, Kwang-Ho
    • Korean Institute of Interior Design Journal
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    • v.25 no.2
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    • pp.50-58
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    • 2016
  • The design of children's hospitals is highly dependent on color schemes. As a space shared together by both adults and children, the design of children's hospitals require color coordination that takes account of the users' characteristics. Visual perception tracking experiment was conducted on the 2 chosen experimental images with a target group made up of adults and children, the following results were found. First, visual attention characteristics of spatial elements' colors were found. The contrast of colors were discovered to effect attention, especially the information desk region showed highest attention. Pillars are subjected to a higher attention relative to other spatial elements, it is suggested when using accent colors to use it only when it is absolutely necessary in partial areas. In contrast, floor patterns were found to be subjected to very low attention relative to other elements. Second, effects of color contrast on visual attention were uncovered. Although color contrast effects attention for both adults and children, children were found to be more effected by color contrast than adults. Especially, children's tendency to rely on color contrast for visual recognition was higher than adults. Since when using only one type on a wide surface children show higher attention on the < vivid > colors than adults, when planning a color coordination for children using < pale > colors instead of < vivid > ones in background for a large surface is seen as a more desired method to increase attention by putting emphasis on the [sharply contrasting] colors.