• Title/Summary/Keyword: Access Category

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Type Drive Analysis of Urban Water Security Factors

  • Gong, Li;Wang, Hong;Jin, Chunling;Lu, Lili;Ma, Menghan
    • Journal of Information Processing Systems
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    • v.16 no.4
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    • pp.784-794
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    • 2020
  • In order to effectively evaluate the urban water security, the study investigates a novel system to assess factors that impact urban water security and builds an urban water poverty evaluation index system. Based on the contribution rates of Resource, Access, Capacity, Use, and Environment, the study adopts the Water Poverty Index (WPI) model to evaluate the water poverty levels of 14 cities in Gansu during 2011-2018 and uses the least variance method to evaluate water poverty space drive types. The case study results show that the water poverty space drive types of 14 cites fall into four categories. The first category is the dual factor dominant type driven by environment and resources, which includes Lanzhou, Qingyang, Jiuquan, and Jiayuguan. The second category is the three-factor dominant type driven by Access, Use, and Capability, which includes Longnan, Linxia, and Gannan. The third category is the four-factor dominant type driven by Resource, Access, Capability, and Environment, which includes Jinchang, Pingliang, Wuwei, Baiyin, and Zhangye. The fourth category is the five-factor dominant type, which includes Tianshui and Dingxi. The driven types impacting the urban water security factors reflected by the WPI and its model are clear and accurate. The divisions of the urban water security level supply a reliable theoretical and numerical basis for an urban water security early warning mechanism.

QoS Fairness in Multimedia Service using Wireless LAN (무선 랜 멀티미디어 서비스의 QoS 공정성 보장)

  • Jin, Hyun-Joon;Park, Nho-Kyung
    • Journal of IKEEE
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    • v.12 no.4
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    • pp.196-203
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    • 2008
  • The IEEE 802.11e working group has announced a new distributed MAC(Medium Access Control) called EDCA(Enhanced Distributed Channel Access) to provide service differentiation among classified traffics. In comparison with the 802.11 legacy MAC, the EDCA provides QoS mechanism by differentiated channel access which is called AC(Access Category) to the frames with different priorities. In multimedia applications, however, the EDCA has some difficulties to achieve QoS throughput because of using fixed AC parameters and never considers overall throughputs, i.e. fairness, for classified services. In this paper, AC parameter control technique is proposed to achieve overall QoS throughputs with differentiated services. The proposed technique controls AC parameters dynamically in real time. Simulation is used to verify the technique and the simulation shows that QoS fairness is improved by 13% in throughput deviation in multimedia environments including voice, video and data service.

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A Study on Relation Analysis between Book and Category in Bibliotherapy Catalog (독서치료 독서목록에서의 카테고리와 치유서의 관계 분석 연구)

  • Baek, Jae Eun
    • Journal of the Korean BIBLIA Society for library and Information Science
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    • v.26 no.2
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    • pp.217-239
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    • 2015
  • For bibliotherapy, users should understand their own life situation, select and access the book (self-help book). User access to book through situation catalog (or list) in reading list, but user is difficult to define and simplify in one word after understanding their own situation. Catalog of bibliotherapy reading list classifies books using one situation category or maximum of two categories other than the age-specific classification. In this study, the author approached and analyzes based on the result of the research on the relationship between bibliotherapy and reading list, in order that access more efficiently to book what user wants. Bibliotherapy reading-list by using mapping and crosswalk between categories, and analyzes category of reading lists through comprehensive review.

The Analysis of Informational Structure and Labeling System of Academic School Websites (대학 웹사이트의 정보구조 및 레이블링 시스템 분석)

  • Lee, Seung-Min;Nam, Tae-Woo;Kim, Seong-Hee
    • Journal of the Korean Society for information Management
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    • v.23 no.2
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    • pp.39-59
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    • 2006
  • In this study we proposed a new informational structure and category labels to fully support the functions of school websites as an access tool to its contents. The proposed model was divided into three main aspects. First, main menu structure was the primary guideline to access information embedded in a website. Therefore, The proposed main menu structure consisted of 9 categories that are commonly provided by 17 existing school websites. Second, first-level categories consisted of total 35 categories under 9 main menu categories. Each category was placed under certain categories in main menu based on the relationships with the meaning of the upper level categories. Third, the proposed model adopted general and comprehensive terms as category labels. The terms used as category labels were based on the analysis of existing category labels, and the most frequently used terms were selected from the current school websites.

Correlation between Pediatric Balance Scale(PBS) and Gross Motor Function Measurement(GMFM) Scores in Children with Cerebral Palsy (뇌성마비 아동의 소아 균형검사(PBS)와 대동작기능평가(GMFM)와의 상관관계)

  • Ko, Myung-Sook;Chung, Jae-Hoon;Jeon, Hye-Seon
    • Journal of the Korean Society of Physical Medicine
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    • v.5 no.2
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    • pp.281-288
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    • 2010
  • Purpose : The purpose of this study was to examine the correlation between Pediatric Balance Scale(PBS) and Gross Motor Function Measurement(GMFM) with cerebral palsy(CP) children. Methods : 31 ambulatory children with CP were recruited for this study. PBS is a modified version of the Berg’s Balance Scale to access the children with motor impairments. To access the motor functions that directly influence to the functional independence of the ambulatory CP children, total scores of standing category and walking/running/jumping category of GMFM were selectively compared with PBS score by Spearman correlation coefficient analysis. Results : The results revealed high correlation between PBS and GMFM scores both in standing and walking/running/jumping categories(r=.9). Conclusions : Therefore, this study indicates that PBS can be applied not only as a tool to access balance, but also as a measurement to predict and access the level of standing and ambulatory related functions of children with CP.

Access delay and packet delay of EDCA in IEEE 802.11e wireless network (IEEE 802.11e EDCA 무선랜의 매체 접속 지연 시간 및 정상 상태에서의 패킷 지연 분석)

  • Lee, Yu-Tae;Jang, Jong-Min;Lee, Key-Sang;Kim, Dong-Il;Kim, Chang-Kyu
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.12 no.8
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    • pp.1420-1426
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    • 2008
  • This paper derives medium access delay of each AC(Access Category) in a stationary station using inter-departure time of IEEE 802.11e WLAN(Wireless LAN). Inter-departure time of IEEE 802.11e WLAN is obtained using saturation throughput of IEEE 802.11e WLAN which was the topic of our prior work. By using a simple queueing model, we evaluate mean queue length and mean delay for each AC on stationary condition. We calculate performance of each AC using this simple model and validate results using simulation.

A study on the Development of Assessment Category and Items for Building Design Evaluation - Focused on the Small and Medium Building - (건축물 디자인 평가를 위한 평가체계 및 평가항목개발에 관한 연구 - 중소형 건축물을 중심으로 -)

  • Ryu, Soo-Hoon
    • Journal of the Korean Institute of Rural Architecture
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    • v.11 no.2
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    • pp.19-27
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    • 2009
  • The purpose of this study is to develop an evaluation category and items for architectural design assessment in attempt to improve design of small scale buildings within Se-Jong City. Some of the domains in existing design assessment are building design, function, environment, and technology. The category and items developed in this study however, is composed to aim for the building's qualitative design assessment. Therefore the architectural assessment tool in this study includes design assessment of the building. Also, assessment category was comprised to verify the design expression used in improving the function and environmental condition of the building. The study was enforced by extracting raw data from existing architectural design related cases. Classification system and assessment category was developed and presented through combination of expert advice, survey, and sample test. In result of this study, the composition system required for design assessment can be divided into five large classifications ; public and harmony, access, form, environmental design, and space. Total of 24 assessment categories are developed and presented. The assessment category and standard presented in this study reflects the distinct regional characteristics and originality of Se-Jong city, creating one of a kind design assessment tool.

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An Adaptive Contention Windows Adjustment Scheme Based on the Access Category for OnBord-Unit in IEEE 802.11p (IEEE 802.11p에서 차량단말기간에 혼잡상황 해결을 위한 동적 충돌 윈도우 향상 기법)

  • Park, Hyun-Moon;Park, Soo-Hyun;Lee, Seung-Joo
    • Journal of the Institute of Electronics Engineers of Korea CI
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    • v.47 no.6
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    • pp.28-39
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    • 2010
  • The study aims at offering a solution to the problems of transmission delay and data throughput decrease as the number of contending On-Board Units (OBU) increases by applying CSMA medium access control protocol based upon IEEE 802.11p. In a competition-based medium, contention probability becomes high as OBU increases. In order to improve the performance of this medium access layer, the author proposes EDCA which a adaptive adjustment of the Contention Windows (CW) considering traffic density and data type. EDCA applies fixed values of Minimum Contention Window (CWmin) and Maximum Contention Window (CWmax) for each of four kinds of Access Categories (AC) for channel-specific service differentiation. EDCA does not guarantee the channel-specific features and network state whereas it guarantees inter-AC differentiation by classifying into traffic features. Thus it is not possible to actively respond to a contention caused by network congestion occurring in a short moment in channel. As a solution, CWminAS(CWmin Adaptation Scheme) and ACATICT(Adaptive Contention window Adjustment Technique based on Individual Class Traffic) are proposed as active CW control techniques. In previous researches, the contention probabilities for each value of AC were not examined or a single channel based AC value was considered. And the channel-specific demands of IEEE 802.11p and the corresponding contention probabilities were not reflected in the studies. The study considers the collision number of a previous service section and the current network congestion proposes a dynamic control technique ACCW(Adaptive Control of Contention windows in considering the WAVE situation) for CW of the next channel.

Design AND IMPLEMENTATION of A News letter system using fuzzy association rules (퍼지 연관규칙을 이용한 뉴스레터 시스템 설계 및 구현)

  • 정연홍;박우수;박규석
    • Journal of Internet Computing and Services
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    • v.3 no.5
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    • pp.41-49
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    • 2002
  • Web mining can be broadly defined as the discovery and analysis of useful information from the World Wide Web. In this paper. we tried to analyze a user access pattern and designed a system which can supply useful information to users through the web mining, The proposed system can search the information of users pattern through the web site and news letters, and pass through classification of category through filtering, The fuzzy association rules are applied to the users who access recently, to each category that generated though these processes, and compares the generated sets to each users-access pages set, and it can send appropriate news letter to each user.

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The design and implementation of security kernel assured trusted path (신뢰경로가 보장되는 보안커널 설계 및 구현)

  • 이해균;김재명;조인준
    • Proceedings of the Korea Institutes of Information Security and Cryptology Conference
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    • 2001.11a
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    • pp.340-347
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    • 2001
  • Security operating system applied to MAC(Mandatory Access Control) or to MLS(Multi Level Security) gives both subject and object both Security Level and value of Category, and it restrict access to object from subject. But it violates Security policy of system and could be a circulated course of illegal information. This is correctly IPC(Interprocess Communication)mechanism and Covert Channel. In this thesis, I tried to design and implementation as OS kernel in order not only to give confidence of information circulation in the Security system, but also to defend from Covert Channel by Storage and IPC mechanism used as a circulated course of illegal information. For removing a illegal information flow by IPC mechanism. I applied IPC mechanism to MLS Security policy, and I made Storage Covert Channel analyze system call Spec. and than distinguish Storage Covert Channel. By appling auditing and delaying, I dealt with making low bandwidth.

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