• Title/Summary/Keyword: combined systems

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Unproved AMC-MIMO Multiplexing Systems Using Selection Transmit Diversities (선택적 전송다이버시티를 사용한 개선된 AMC-MIMO 다중화시스템)

  • Kang, Min-goo
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.7 no.4
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    • pp.652-657
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    • 2003
  • In this paper, Adaptive Modulation and Coding (AMC) is combined with Multiple Input Multiple Output (MIMO) multiplexing to improve the throughput performance of AMC. In addition, a system that adopts Selection Transmit Diversity (STD) in the AMC-MIMO multiplexing system is proposed. The received SNR is improved by adopting STD techniques. And it increases probability of selecting MCS (Modulation and Coding Scheme) level that supports higher data rate. This leads to an increased throughput of the AMC-MIMO system. STD in our simulation selects 2 transmission antennas from 4 antennas and AMC-MIMO multiplexing process operates with the selected antennas. The computer simulation is performed in flat Rayleigh fading channel. The results show that the proposed system achieves a gain of 1Mbps over the AMC-MIMO multiplexing system with the same number of antennas at 15dB SNR.

Blackbox-Based a Vehicle Emergency Situation Detection and Notification System (블랙박스 기반의 차량용 응급상황 감지 및 통보시스템)

  • Kwon, Doo-Wy;Lee, Hoon-Jae;Park, Su-Hyun;Do, Kyeong-Hoon
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.14 no.11
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    • pp.2423-2428
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    • 2010
  • The number of motor vehicle registrations in Korea is increasing steadily each year, driven by industry development and economic growth. The number of traffic accidents is also rapidly increasing. Korea has a relatively high number of traffic accidents among OECD member countries, and it ranks among the highest in traffic accident death rates. This death rate is higher compared to death rates as a proportion of the number of traffic accidents in each country. It is very common for drivers to lose consciousness in traffic collisions, which leads to a failure to carry out early emergency measures. In order to prevent such situations as well as hit-and-runs and people left uncared for after traffic accidents, there is a need for motor vehicle black boxes and accident report systems. This study addressed the need for an emergency evacuation system for people injured in traffic accidents and a secondary traffic accident prevention system by developing a motor vehicle emergency situation detection and report system combined with a black box, and materializing it as an actual system.

Nonlinear Vibration Analyses of Stiffened Composite Panels under Combined Thermal and Random Acoustic Loads (열-랜덤 음향 하중을 받는 보강된 복합재 패널의 비선형 진동 해석)

  • Choi, In-Jun;Lee, Hong-Beom;Park, Jae-Sang;Kim, In-Gul
    • Journal of the Korea Institute of Military Science and Technology
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    • v.23 no.6
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    • pp.533-541
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    • 2020
  • This study using ABAQUS investigates the nonlinear vibration responses when thermal and random acoustic loads are applied simultaneously to the stiffened composite panels. The nonlinear vibration analyses are performed with changing the number of stiffeners, and layup condition of the skin panel. The panel and stiffeners both are modeled using shell elements. Thermal load (ΔT) is assumed to have the temperature gradient through the thickness direction of the stiffened composite panel. The random acoustic load is represented as stationary white-Gaussian random pressure with zero mean and uniform magnitude over the panels. The thermal postbuckling analysis is conducted using RIKS method, and the nonlinear dynamic analysis is performed using Hilber-HughesTaylor time integration method. When ΔT = 25.18 ℃ and SPL = 105 dB are applied to the stiffened composite panel, the effect of the number of stiffener is investigated, and the snap-through responses are observed for composite panels without stiffeners and with 1 and 3 stiffeners. For investigation of the effect of layup condition of the skin panel, when ΔT = 38.53 ℃ and SPL = 110 dB are applied to the stiffened composite panel, the snap-through responses are shown when the fiber angle of the skin panel is 0°, 30°, and 60°.

A Study on role of Science Museum for STEAM Education (융합교육에 있어서 과학관의 역할 연구)

  • Yoon, Young-doo;Choi, Hun
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.19 no.6
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    • pp.1353-1358
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    • 2015
  • The creative economy is the industrialization era, the information age, knowledge-based economy, linking the new economic paradigm. The core words of the creative economy are stand for creativity, innovation, consumer protection and utilization of intellectual property. Creative ideas are combined with software technology will make innovative ecosystem-based structured market such as Apple, Google, Facebook. Intangible assets attributable to creativity than ever before in human history that is important as the economic value. In addition, innovative ideas, creativity and economic growth beyond the knowledge and information society is required. Because the core has a fusion of science and technology, industry, culture and industry convergence, various genres of creative activity support, and cultural and high-tech fusion industries, such as content creation and job creation through economic traction is needed. In this study, we analyze the case of the US Smithsonian Institution proposes the direction of Science Museum in creative workforce.

Security Check Scheduling for Detecting Malicious Web Sites (악성사이트 검출을 위한 안전진단 스케줄링)

  • Choi, Jae Yeong;Kim, Sung Ki;Min, Byoung Joon
    • KIPS Transactions on Computer and Communication Systems
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    • v.2 no.9
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    • pp.405-412
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    • 2013
  • Current web has evolved to a mashed-up format according to the change of the implementation and usage patterns. Web services and user experiences have improved, however, security threats are also increased as the web contents that are not yet verified combine together. To mitigate the threats incurred as an adverse effect of the web development, we need to check security on the combined web contents. In this paper, we propose a scheduling method to detect malicious web pages not only inside but also outside through extended links for secure operation of a web site. The scheduling method considers several aspects of each page including connection popularity, suspiciousness, and check elapse time to make a decision on the order for security check on numerous web pages connected with links. We verified the effectiveness of the security check complying with the scheduling method that uses the priority given to each page.

Off-Line Electronic Payment Scheme using Smart Cards (스마트 카드를 사용한 오프 -라인 전자 지불 기법)

  • Kim, Jeong-Eun;Lee, Hyeong-U;Kim, Tae
    • Journal of KIISE:Computer Systems and Theory
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    • v.26 no.11
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    • pp.1363-1372
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    • 1999
  • 에이전트 기반 이동 컴퓨팅 환경에서 전자 상거래를 구현하기 위해 가장 필요로 하는 것은 안전한 지불 구조를 제공하는 것이다. 본 연구에서는 불확정 전송 기법 1,2 을 사용한 비대화형 엔티티 인증 기법과 Horster 기법 4,5 을 기반으로 메시지 복원 기능을 제공하는 공정 은닉 서명 기법을 제시한다. 또한 이를 직접 Brands가 제시한 오프-라인 전자 지불 시스템 3,6 에 접목한다. 인증 단계가 비대화형으로 수행되므로 이동 엔티티 인증에 효율적이고, 메시지 복원 기능을 갖고 공개 검증 기능을 제공하는 은닉 서명을 적용하기 때문에 카운터 방식을 사용한 스마트 카드 기반 전자 지불 시스템 6 에 효과적으로 적용할 수 있었다. 전자 화폐에 대해서 신뢰 센터에 의한 공정성 검토 기능을 추가로 제공하므로 전자 지불 시스템의 신뢰성을 향상시킬 수 있다.Abstract The primary requirements for realizing the electronic commerce in agent based mobile computing environments are to implement the compatible secure payment framework. In this paper, we propose both the non-interactive entity authentication scheme that is combined with oblivious transfer protocol 1,2 and the message recovery fair blind signature based on Horster scheme 4,5 . And these techniques are directly applied to the Brand's off-line electronic payment system 3,6 . As the authentication processes are done by non-interactive manner, we can also get efficiency for mobile entity authentication. Additionally, as the used signature scheme provides a message recovery function with publicly verifiable properties, it is efficiently applicable to a counter based off-line electronic payment scheme 6 based on the additional device like smart card. Therefore, we can enhance the reliability of proposed electronic payment system based on the publicly verifiable fairness in its electronic cash by a trusted judge.

Development of the Korean Mid- and Upper-Level Aviation Turbulence Guidance (KTG) System Using the Regional Unified Model (통합지역모델을 이용한 한국형 중·상층 항공난류예측시스템 개발)

  • Kim, Jung-Hoon;Chun, Hye-Yeong
    • Atmosphere
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    • v.21 no.4
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    • pp.497-506
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    • 2011
  • Korean mid- and upper-level aviation turbulence guidance (KTG) system is developed using the unified model (UM)-based regional data assimilation and prediction system (RDAPS) of the Korea Meteorological Administration. The KTG system includes three steps. First, the KTG system calculates a suite of diagnostics in the UM-RDAPS domain. Second, component diagnostics that have different units and numerical magnitudes are normalized into the values between 0 and 1, according to their own thresholds in the KTG system. Finally, normalized diagnostics are combined into one KTG predictor by measuring the weighting scores based on the probability of detection, which is calculated using the observed pilot reports (PIREPs) exclusively of moderate-or-greater (MOG) and null (NIL) intensities. To investigate the optimal performance of the KTG system, two types (RD-KTG and UM-KTG) of the KTG systems are developed and evaluated using the PIREPs over Korea and East Asia. Component diagnostics and their thresholds in the RD-KTG are founded on the 8-yrs (2002.12-2010.11) MM5-based RDAPS (previous version of the RDAPS; ${\Delta}x$ = 30 km) and PIREPs data, while those in the UM-KTG are based on the 6 months (2010.12-2011.5) UM-based RDAPS (${\Delta}x$ = 12 km) and PIREPs data. In comparison between the RD-KTG and UM-KTG, overall performance of the UM-KTG (0.815) is better than that of the RD-KTG (0.79) during the recent 6 months, because forecasting skill for the upper-level wind is higher in the UM-RDAPS than in the MM5-RDAPS. It is also found that the UM-KTG is more efficient than the RD-KTG according to the statistical evaluations and sensitivity tests to the number of component diagnostics.

The Methods and Its Application of Long Distance Trail Planning in a Mountainous Region (산악지역에서의 장거리 트레일 조성 계획방법 및 적용)

  • Hwang, Guk-Woong;Jang, Byoung-Kwan
    • Journal of Korean Society of Rural Planning
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    • v.17 no.3
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    • pp.55-65
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    • 2011
  • Long distance trail or trail system planning is the first important step in transforming your vision into reality. Planning presents a vision for a trail or trail system and brings a comprehensive, long-range perspective. The master plan provides solid, credible recommendations for developing a trail or trail system that is safe, convenient, well used, supported by local residents, practicality to implement, and customized to meet the needs of the community, you will need to follow a logical planning. The key elements of master planning includes site assessment, vision, goals and objectives, routing and design, implementation strategies. Trails or trail systems should provide linkages to popular destinations, safely accommodate a variety of users, and be sensitive to any negative impacts on the natural environment and wildlife. Trails planners also need to think about how the trail, or trail system will function in the future as areas are developed or trail population increases. All of these factors during the planning process will ensure the existence of high-quality facilities for years to come. Project for Nakdong-jungmaek trail planning combine long distance trail with circuit way. That project is a planning brought out the best in each of Tokai natural way and Cotswold way. That is planning which is combined a wooded trail in Tokai natural way with access and facilities improving economy in Cotswold way. Also That planning embraces a core cultural center which is concerned forest or wood to come more people.

Personalized TV Program Recommendation in VOD Service Platform Using Collaborative Filtering (VOD 서비스 플랫폼에서 협력 필터링을 이용한 TV 프로그램 개인화 추천)

  • Han, Sunghee;Oh, Yeonhee;Kim, Hee Jung
    • Journal of Broadcast Engineering
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    • v.18 no.1
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    • pp.88-97
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    • 2013
  • Collaborative filtering(CF) for the personalized recommendation is a successful and popular method in recommender systems. But the mainly researched and implemented cases focus on dealing with independent items with explicit feedback by users. For the domain of TV program recommendation in VOD service platform, we need to consider the unique characteristic and constraints of the domain. In this paper, we studied on the way to convert the viewing history of each TV program episodes to the TV program preference by considering the series structure of TV program. The former is implicit for personalized preference, but the latter tells quite explicitly about the persistent preference. Collaborative filtering is done by the unit of series while data gathering and final recommendation is done by the unit of episodes. As a result, we modified CF to make it more suitable for the domain of TV program VOD recommendation. Our experimental study shows that it is more precise in performance, yet more compact in calculation compared to the plain CF approaches. It can be combined with other existing CF techniques as an algorithm module.

Railway Investment and Operation combined with Accessibility and Transfer Systems (연계환승 교통체계를 감안한 철도투자 및 운영방안)

  • Kim, Si Gon;Mun, Ye Up
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.36 no.1
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    • pp.129-133
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    • 2016
  • This paper insists that the accessibility and transfer facility has also to be included in railway investment because railway mode can not be, what is called, a door to door service. At present those facility are not included in the railway investment with them in negligence. Since those facility is not treated with railway system there is no room to get a budget from the central government. This paper suggests that all the measurements have to be implemented, based on the LOS (Level of Service) of accessibility and transfer at railway stations. The LOS has to be as low as reasonably practical (ALARP) which can be derived from the consensus between government and citizens. Also, a couple of procurement methods are suggested for accessibility and transfer facility separately. Finally, improvement of regulations are also suggested.