• Title/Summary/Keyword: Spread system

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Analysis on Radio Communication Characteristics of LTE Railway Network (철도통합무선망(LTE-R)의 무선통신특성 분석)

  • Yoon, Byungsik;Lee, Sook-Jin;Kim, Dong Joon;Sung, Dong Il
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.21 no.9
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    • pp.1-8
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    • 2020
  • The Ministry of Land, Infrastructure and Transport of Korea has been trying to spread integrated railway communication network technologies based on a major railway policy since 2012. As a result, the world's first commercial Long-Term Evolution - Railway (LTE-R) network was established on the Gangneung line (Manjong station - Gangneung station) and has been commercially operating as a railway communication system since 2017. Special function and performance requirements are needed for safe and efficient railway operations, such as group calls, emergency calls, functional addressing, and train control based on wireless communications. In this paper, we present functional and performance railway communications requirements that are based on European wireless railway communications systems. In addition, we measured communications characteristics and performance using a KTX field test on the Gangneung line to analyze the validity and reliability of the LTE-R network. Although the average Radio Frequency (RF) conditions were satisfied in the requirements, we found sudden communications quality degradation, such as Radio Link Failure (RLF) in some railway sections. We propose a way to improve performance and network installations based on in-depth analysis of LTE-R communications field-test results.

Scoping for Marine Environmental Impact Assessment of Tidal Power Plant Construction (조력에너지 개발사업의 해양환경영향평가 스코핑 방안)

  • Kam, Min-Jae;Kim, Gui-Young;Jeon, Kyeong-Am;Yu, Jun;Lee, Dae-In;Eom, Ki-Hyuk
    • Journal of the Korean Society for Marine Environment & Energy
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    • v.15 no.1
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    • pp.30-37
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    • 2012
  • This paper assessed environmental impact of tidal power plant construction in the western sea of Korea, and diagnosed problems of the related assessment. We also proposed key assessment items (scoping) and system improvement for environmental impact assessment (EIA). The establishment of a broad consensus of the appropriateness and a clear purpose for business is an important aspect of the aptness of using the waters, and the aggressive collecting of opinions of the stakeholder and institutions will have to be fulfilled. In addition, we presented the following scoping plan in order to minimize the negative effects of the marine ecosystem and the conflict between the people who work in the fishing industry which result due to the construction of the tidal power plants. (1) the change in seawater exchange rates and the aspect of erosion/sedimentation which result from the change in the velocity of running fluid, (2) the destruction of spawns/habitats of fish due to the damage of tidal flats, (3) fishery resources, impacts of fishing grounds, and the spread of suspended sediments, etc. will have to be applied to the key assessment items(scoping). In addition, every citizen will have work hard for an establishment of an active plan which achieves the harmony and balance of environmental preservation and for the policy to be applied through changing their consciousness of environmental preservation.

Analysis on designer's cognitive thinking process in 3D animation design (3D 애니메이션 제작을 위한 디자이너의 인지적 사고과정 분석)

  • Kim, Kie-Su
    • Cartoon and Animation Studies
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    • s.20
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    • pp.1-14
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    • 2010
  • The success of a three-dimensional blockbuster movie, AVARTA, brought an public attention on the expansion of three-dimensional computer applications, and it allows experts predict further hardware technology developments to support the such applications. Futhermore, an internet based infra structure and three-dimensional structure, third generation network community, advanced computer networks have influenced advancement in computer technology within the 3D game industry and the spread of 2D computer animation technologies. This advancement of computer technologies allow the industry to overcome a limitation of generating cultural design contexts existed within 2D network community. However, despite of the expansion of 2D and 3D computer technologies, a limitation of analysing designers' intentions on morphology of digital contents and user interface still exists. Therefore, the purpose of this study is to analyze (1) present conditions of the 3D industry and (2) protocols of designers' cognitive design processes based on their design communication, contents, and tools. Analysis was conducted based on literature reviews and case precedent analyses. For the analysis, a 2D Avarta sketch character was designed and then applied into a 3D game system. Observations how designers solve cultural problem within the structure via Avarta were conducted. Outcomes were then coded for further analysis.

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Spatial Analysis of Oak Wilt Disease in Bukhansan Mountain Park Using Spatial Data of Damaged Trees (피해목 위치자료를 이용한 북한산 국립공원 참나무시들음병 공간분석)

  • Zhu, Yongyan;Piao, Dongfan;Lee, Woo-kyun;Jeon, Seong-Woo
    • Korean Journal of Remote Sensing
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    • v.33 no.5_3
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    • pp.879-888
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    • 2017
  • This study is a preliminary research conducted in Buhansan mountain National Park to develop a management system to predict and control oak wilt disease by indicating spatial factors which affect diffusion of the disease. After analysing altitude factor during the estimation of spatial analysis of damaged area, it is indicated that damaged trees are mainly distributed at altitude of 200-500 m and number decreased drastically over the altitude of 500 m. The result showed that 92% of total damaged trees are on slope between 20~40 degrees and the number decreased drastically on slope steeper than 40 degrees. It is indicated that damaged area is mainly distributed on southern aspect. It is estimated by using CART that slope factor affected the diffusion of disease mostly but aspect factor did not. Surface temperature and altitude showed similar effect.By simulating possible diffusion scenario, it is estimated that the disease could spread to DO-BONG Mt., northeast of Bukhansan mountain.

A Study on the Relationship between Justice Perception of Franchise and Trust, Switching Barriers of the Franchisee in the Barriers and Beauty Parlors Business (이.미용업에서의 프랜차이즈 공정성 지각이 신뢰와 전환장벽에 미치는 영향)

  • Kim, Kyeong Ran;Ryu, Hwang Gun;Oh, Chang Seok
    • The Korean Journal of Health Service Management
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    • v.1 no.1
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    • pp.75-89
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    • 2007
  • The start point of a franchise system such as Lotteria was in 1979. Since 1990, the franchise systems in Korea have rapidly spread over all industry types. As 'Franchise Law' was enforced in 2002, the expansion of a franchise picked up its' speed. The barbers and beauty parlors business has the same expansion trend. However, there was no study about the franchise systems in the barbers and beauty parlors business. The purpose of this study was to find the goodness of fit of the structured equation model proposed and identify the significances of relationships in the variables of justice perceptions, trust, satisfactions, business performances, switching barriers, switching cost etc. This study tries to find a solution for a good development between franchisor and franchisee in the barbers and beauty parlors business in Korea. The theoretical considerations about justice of this study is limited in reciprocal relation justice and procedure justice. And it did make simplify for trust, satisfaction, business performance, switching barrier. And switching barrier did measure as dimension of switching coot. From October 26, 2005 to October 29, this study collected 250 survey questionnaires from the franchisees located in Seoul, Busan, Daegu, Ulsan, and Keoyng-Nam. In analyses of using SPSS Windows 11.0 and LISREL 8.14, this study used 208 cases because 48 cases did not response appropriately. Tn conclusions. reciprocal justice perception and procedure justice jointly determined trust. Secondly, reciprocal justice perception significantly determined satisfaction. Procedure justice perception negatively determined satisfaction, but this relationship was not significant. Thirdly, reciprocal justice perception positively influenced business performance, and procedure justice negatively influenced business performance, but the last relationship was not significant Fourthly, trust positively significantly influenced satisfaction and business performance. Fifthly, satisfaction positively influenced business performance and true determined switching barrier positively. This study shows following: firstly, a composition concept did make structural relationship and secondly, a reciprocal relation justice of a franchisor did appear as an important variable and it gives positive influence to trust, satisfactions, business performance, switching barriers of the franchisees.

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Construction of Environmental Friendly Special-Purpose Ship for the Removal of Blue-green Algae (친환경적 녹조 제거용 특수선박 건조)

  • Shin, Jae-Ki;Yi, Hye-Suk;Jeong, Sun-A;Hwang, Soon-Jin
    • Korean Journal of Ecology and Environment
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    • v.42 no.3
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    • pp.404-406
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    • 2009
  • This study note wished to introduce special-purpose ship for algae removal that is developed by core technology of our country. The ship is consisted of main frame and adjuvant that can attach and detach as cross (+) shape of a character. The characteristics of ship are super light weight and low draft. That is consisted of four devices as suction, collection, filtration and recovering units. Among these, filtration used screen filter (mesh size 30 ${\mu}m$). Also, can separate and remove water and algae by compression air participle notion. Percentage of moisture content of concentrated algal particle was 85%. Water parted with algae finally is exhausted to water area. Removal efficiency that compare by chlorophyll-$\alpha$ concentration was about 57% (inflow: 83.2 ${\mu}g\;L^{-1}$, outflow: 35.8 $[\mu}g\;L^{-1}$) without physical and chemical pretreatment. Forward, need to achieve effect test in various conditions (algal biomass, flow etc.) for efficiency and technological elevation of exclusion device. We wished to contribute in presuppression system construction of massive algal development that manage blue-green algae occurrence area effectively, and prevents spread as lower part of reservoir.

Development of Gait Event Detection Algorithm using an Accelerometer (가속도계를 이용한 보행 시점 검출 알고리즘 개발)

  • Choi, Jin-Seung;Kang, Dong-Won;Mun, Kyung-Ryoul;Bang, Yun-Hwan;Tack, Gye-Rae
    • Korean Journal of Applied Biomechanics
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    • v.19 no.1
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    • pp.159-166
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    • 2009
  • The purpose of this study was to develop and automatic gait event detection algorithm using single accelerometer which is attached at the top of the shoe. The sinal vector magnitude and anterior-posterior(x-axis) directional component of accelerometer were used to detect heel strike(HS) and toe off(TO), respectively. To evaluate proposed algorithm, gait event timing was compared with that by force plate and kinematic data. In experiment, 7 subjects performed 10 trials level walking with 3 different walking conditions such as fast, preferred & slow walking. An accelerometer, force plate and 3D motion capture system were used during experiment. Gait event by force plate was used as reference timing. Results showed that gait event by accelerometer is similar to that by force plate. The distribution of differences were spread about $22.33{\pm}17.45m$ for HS and $26.82{\pm}14.78m$ for To and most error was existed consistently prior to 20ms. The difference between gait event by kinematic data and developed algorithm was small. Thus it can be concluded that developed algorithm can be used during outdoor walking experiment. Further study is necessary to extract gait spatial variables by removing gravity factor.

A Fundamental Study about a Quality Certification of 3D Precision Indoor Geospatial Information - Focused on Yeongdeungpo Station - (3차원 정밀 실내공간정보 품질인증 방안에 관한 기초연구 - 영등포역을 중심으로-)

  • Lee, Ki Sung;Jeong, In Hun;Choi, Yun Soo;Kim, Sang Bong
    • Journal of Korean Society for Geospatial Information Science
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    • v.23 no.1
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    • pp.3-14
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    • 2015
  • As buildings in the downtown area, such as the complex building connected to the skyscraper and the underground facility, have become large and complex, the range of target domain of the space information service is rapidly expanding to the interior space; it is considered that this change will create various demands of service such as the indoor geospatial information base safety, the management of facility, and the interior navigation in the future, along with spread of mobile devices and development of IT technology. As for the indoor geospatial information, however, there is no certification standard of the established indoor geospatial information data quality, so preparing the certification standard is urgent. Thus, this study reviewed foreign and domestic research cases and prepared measures for quality verification of the indoor geospatial information to conduct a verification test of the Yeongdeungpo Station indoor geospatial information, established in 2014. As a result, through the verification test of the method and standard of the indoor geospatial information quality certification suggested by this research, it was identified that the uniform and higher quality data could be classified, and the types of error high frequently occurring could be investigated. These results are expected to be utilized as the basic data for establishing quality certification system for the indoor geospatial information in the future.

Study on the Operation Characteristics of Heat Detectors through Fire and Wind Tunnel Experiment (풍동실험과 화재실험을 통한 열감지기의 동작특성에 관한 연구)

  • Ryu, Hocheol;Kim, Doohyun
    • Journal of the Society of Disaster Information
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    • v.11 no.2
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    • pp.203-209
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    • 2015
  • The heat detector detects heat in the fire and is an important core element of the automatic fire alarm system used generally for every fire prevention objects. The heat detector is distinguished in spot type and spread type and in spot type, there are differential and thermistor types. These heat detectors give a great influence on the loss of people and property according to the sensitivity of response such as operation time and operation temperature in actual fire and in overseas people apply it for the development of products that can be operated in the early stage of fire including certification, quality management, and comparison standard by introducing response time index through the theory of heat balance that considers the heat loss and ventilation tests. In Korea, the response time index is introduced and used in the head of sprinkler products, but it is not applied to the heat detector at present. It is necessary to introduce the response time index that shows the sensitivity of response of the heat detector the installation standard for the heat detector that the response time index is applied should be different according to the fire weight, danger degree of fire, and shape of buildings. Through this study, it tries to help reduce lives and property of people through the swift warning by installing detectors suitable for the building structure.

A Practical New Technology of Removing Algal Bloom: K-water GATe Water Combine (조류(藻類)제어를 위한 실용적 신기술 : K-water 녹조수상콤바인)

  • Shin, Jae-Ki;Kim, Hojoon;Kim, Sea Won;Chong, Sun-A;Moon, Byong Cheun;Lee, Sanghyup;Choi, Jae Woo
    • Korean Journal of Ecology and Environment
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    • v.47 no.3
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    • pp.214-218
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    • 2014
  • We introduce a technical equipment of GATe (Green (algae)-tide) water combine developed by K-water. The GATe water combine consists of five modules: main body and buoyant, transfer hopper, screen conveyer, sludge remover, and separator of algae and waste. Also a sprinkler, as the pre-treatment step if necessary, is equipped to the device to spread out environmental-friendly algaecide under the circumstance that the level of algal bloom does not reach to the scum-forming condition. The overall module system of this device is very simple. Based on the field test, the device covers surface area of ca. $500,000m^2day^{-1}$ during the period from May to July, and treats water volume as much as $500,000m^3day^{-1}$ in spite of some variation depending on the water quality condition. The removal efficiency of the device appeared to be over 90%. In addition, the operating duration of the device was able to expand to cover the period between March and November. We expect this new technology can be used to solve algal bloom problems in drinking water resource and public water area.