• Title/Summary/Keyword: Existing system

Search Result 16,192, Processing Time 0.045 seconds

Analysis of LDC Message Reception Performance of Korean eLoran Pilot Service according to Modulation Methods (첨단 지상파항법시스템(eLoran) 시범서비스의 LDC 메시지 변조기법에 따른 수신성능 분석)

  • Pyo-Woong, Son;Sak, Lee;Tae Hyun, Fang;Kiyeol, Seo
    • Journal of Navigation and Port Research
    • /
    • v.46 no.6
    • /
    • pp.525-529
    • /
    • 2022
  • In the eLoran system, the Loran Data Channel (LDC) is used to provide precise timing and positioning. The LDC message can be modulated with the Eurofix method, which modulates the transmission time of the 3rd-8th pulse not used for navigation, and the 9th pulse method, which modulates data using the 9th additional pulse after the existing 8 Loran pulses. In this paper, we analyzed the reception performance of the LDC message transmitted from the eLoran transmitter according to the modulation method. The eLoran testbed transmitter in Incheon was set to transmit LDC messages simultaneously with the 9th pulse modulation method and the Eurofix modulation method. Then, the LDC messages stored in the databases of the eLoran differential stations in Incheon and Pyeongtaek were analyzed in terms of the message reception rate according to the modulation method. Using the navigation aid management ship Inseong No. 1, the range of LDC message reception of actual sea users near Incheon Port was also analyzed. The results of this study are expected to be utilized in the full operational capability service after the eLoran pilot service.

A CFD Study on Aerodynamic Performances by Geometrical Configuration of Guide Vanes in a Denitrification Facility (탈질 설비 내 안내 깃의 기하학적 형상에 따른 공력 성능에 대한 전산 해석적 연구)

  • Chang-Sik, Lee;Min-Kyu, Kim;Byung-Hee, Ahn;Hee-Taeg, Chung
    • Clean Technology
    • /
    • v.28 no.4
    • /
    • pp.316-322
    • /
    • 2022
  • The flow pattern at the inlet of the catalyst layer in a selective catalytic reduction (SCR) system is one of the key parameters influencing the performance of the denitrification process. In the curved diffusing parts between the ammonia injection grids and the catalyst layers, guide vanes are installed to improve flow uniformity. In the present study, a numerical simulation has been performed to investigate the effect of the geometrical configuration of the guide vanes on the aerodynamic characteristics of a denitrification facility. This application has been made to the existing SCR process in a large-scaled coal-fired power plant. The flow domain to be solved covers the whole region of the flow passages from the exit of the ammonia injection gun to the exit of the catalyst layers. ANSYS-Fluent was used to calculate the three-dimensional steady viscous flow fields with the proper turbulence model fitted to the flow characteristics. The root mean square of velocity and the pressure drop inside the flow passages were chosen as the key performance parameters. Four types of guides vanes were proposed to improve the flow quality compared to the current configuration. The numerical results showed that the type 4 configuration was the most effective at improving the aerodynamic performance in terms of flow uniformity and pressure loss.

Comparison and Analysis of Drought Index based on MODIS Satellite Images and ASOS Data for Gyeonggi-Do (경기도 지역에 대한 MODIS 위성영상 및 지점자료기반 가뭄지수의 비교·분석)

  • Yu-Jin, KANG;Hung-Soo, KIM;Dong-Hyun, KIM;Won-Joon, WANG;Han-Eul, LEE;Min-Ho, SEO;Yun-Jae, CHOUNG
    • Journal of the Korean Association of Geographic Information Studies
    • /
    • v.25 no.4
    • /
    • pp.1-18
    • /
    • 2022
  • Currently, the Korea Meteorological Administration evaluates the meteorological drought by region using SPI6(standardized precipitation index 6), which is a 6-month cumulative precipitation standard. However, SPI is an index calculated only in consideration of precipitation at 69 weather stations, and the drought phenomenon that appears for complex reasons cannot be accurately determined. Therefore, the purpose of this study is to calculate and compare SPI considering only precipitation and SDCI (Scaled Drought Condition Index) considering precipitation, vegetation index, and temperature in Gyeonggi. In addition, the advantages and disadvantages of the station data-based drought index and the satellite image-based drought index were identified by using results calculated through the comparison of SPI and SDCI. MODIS(MODerate resolution Imaging Spectroradiometer) satellite image data, ASOS(Automated Synoptic Observing System) data, and kriging were used to calculate SDCI. For the duration of precipitation, SDCI1, SDCI3, and SDCI6 were calculated by applying 1-month, 3-month, and 6-month respectively to the 8 points in 2014. As a result of calculating the SDCI, unlike the SPI, drought patterns began to appear about 2-month ago, and drought by city and county in Gyeonggi was well revealed. Through this, it was found that the combination of satellite image data and station data increased efficiency in the pattern of drought index change, and increased the possibility of drought prediction in wet areas along with existing dry areas.

Seismic Performance-Based Design for Breakwater (방파제의 성능기반 내진설계법)

  • Kim, Young-Jun;Park, Inn-Joon
    • Journal of the Korean Geotechnical Society
    • /
    • v.38 no.12
    • /
    • pp.91-101
    • /
    • 2022
  • The 1995 Kobe earthquake caused a massive damage to the Port of Kobe. Therefore, it was pointed out that it was impossible to design port structures for Level II (Mw 6.5) earthquakes with quasi-static analysis and Allowable Stress Design methods. In Japan and the United States, where earthquakes are frequent, the most advanced design standards for port facilities are introduced and applied, and the existing seismic design standards have been converted to performance-based design. Since 1999, the Korean Port Seismic Design Act has established a definition of necessary facilities and seismic grades through research on facilities that require seismic design and their seismic grades. It has also established a performance-based seismic design method based on experimental verification. In the performance-based seismic design method of the breakwater proposed in this study, the acceleration time history on the surface of the original ground was subjected to a fast Fourier transform, followed by a filter processing that corrected the frequency characteristics corresponding to the maximum allowable displacement with respect to performance level of the breakwater and the filtered spectrum. The horizontal seismic coefficient for the equivalent static analysis considering the displacement was calculated by inversely transforming (i.e., subjected to an inverse fast Fourier transform) into the acceleration time history and obtaining the maximum acceleration value. In addition, experiments and numerical analysis were performed to verify the performance-based seismic design method of breakwaters suitable for domestic earthquake levels.

The Transformation of Norms and Social Problems: Focusing on the COVID-19 Pandemic (규범의 전환과 사회문제: 코로나를 중심으로)

  • Lee, Jangju
    • Korean Journal of Culture and Social Issue
    • /
    • v.28 no.3
    • /
    • pp.513-527
    • /
    • 2022
  • This study was conducted to examining the socio-cultural impact of the COVID-19 pandemic that swept the world around 2020, and the transformation of norms and social problems due to COVID-19. For this, the characteristics of changes in the socio-cultural norms of the 14th century European Black Death, a representative example of the pandemic, were derived, and based on this, the COVID-19 pandemic was analyzed. The Black Death served as an opportunity to change social norms based on the existing religious authority and the power of the feudal system to the Enlightenment. The population declination and labor shortage also promoted commercialization and mechanization. Printing, which spread during this period, led to the popularization of knowledge, which raised the level of thinking and led to epochal scientific development. This became the foundation of the Industrial Revolution. Like the recent Black Death, COVID-19 has triggered changes in social norms. The technological environment of metaverse, a mixture of virtual and reality, has changed the norm of a consistent identity into free and open identities exerting various potentials through alternate characters. In addition, meme, which are about people being friendly to those with the same worldview as him on the metaverse, weakened the sense of isolation in non-face-to-face situations. Artificial intelligence (AI), which developed during the COVID-19 pandemic, has entered the stage of being used for creative activities beyond the function of assisting humans. Discussions were held on what new social problems would be created by the social norms changed due to the COVID-19 pandemic.

A Study on Family Support Service for Adoptive Families in terms of Necessity and Role of the Family Center (가족센터(구 건강가정지원센터)의 입양가족 대상 서비스 제공의 필요성과 역할 정립에 관한 연구)

  • Lee, Sunhyung;Bae, Jiyeon
    • Journal of Family Resource Management and Policy Review
    • /
    • v.26 no.2
    • /
    • pp.1-17
    • /
    • 2022
  • This study provides a critical analysis of the Family Center's programs for adoptive families by interviewing employees at these centers and at Adoption Agencies who have experiences with adoption programs. For this study, nine such workers from three separate Family Centers and three such workers from two separate Adoption Agencies have (voluntarily) engaged in in-depth interviews. Major findings from the interviews are that the Family Centers were initially motivated to carry out adoption family programs for three principal reasons: they located many families (in need of adoption family program); potential adoptees were interested in the program; adoption families participated in the pre-existing programs such as Self-help Group and Co-parenting Space. Workers in the study also reported that they approach to an adoption family and their contemplation on ways to provide better services to the adoption families. They don't have any official and formal manual or guidelines from the Government Ministries and offices such as Korean Institute for Healthy Family; as a result, the workers at Family Centers have endeavored to gain connection with Adoption Agencies in hopes of cooperation with them and to improve the services at Family Centers. For benefits of Family Centers as a delivery system, they mentioned nationwide infrastructure, family professional, and arrangement of integrated program for family. For improvements, they listed awareness education based on a thorough consideration of adoptee's varied characteristics, close cooperation with adoption institutions, provision of basic operational manual from Korean Institute for Healthy Family, and governmental efforts to enlarge the consideration pool for families.

Implementation of a Transition Rule Model for Automation of Tracking Exercise Progression (운동 과정 추적의 자동화를 위한 전이 규칙 모델의 구현)

  • Chung, Daniel;Ko, Ilju
    • KIPS Transactions on Computer and Communication Systems
    • /
    • v.11 no.5
    • /
    • pp.157-166
    • /
    • 2022
  • Exercise is necessary for a healthy life, but it is recommended that it be conducted in a non-face-to-face environment in the context of an epidemic such as COVID-19. However, in the existing non-face-to-face exercise content, it is possible to recognize exercise movements, but the process of interpreting and providing feedback information is not automated. Therefore, in this paper, to solve this problem, we propose a method of creating a formalized rule to track the contents of exercise and the motions that constitute it. To make such a rule, first make a rule for the overall exercise content, and then create a tracking rule for the motions that make up the exercise. A motion tracking rule can be created by dividing the motion into steps and defining a key frame pose that divides the steps, and creating a transition rule between states and states represented by the key frame poses. The rules created in this way are premised on the use of posture and motion recognition technology using motion capture equipment, and are used for logical development for automation of application of these technologies. By using the rules proposed in this paper, not only recognizing the motions appearing in the exercise process, but also automating the interpretation of the entire motion process, making it possible to produce more advanced contents such as an artificial intelligence training system. Accordingly, the quality of feedback on the exercise process can be improved.

The Research about Literature Museum Network Organization and Operation plan for Establishment of Literature Promotion Infrastructure (문학 진흥 인프라 구축을 위한 문학관 네트워크 조직 및 운영 방안 연구)

  • Che, Keunbyung
    • 지역과문화
    • /
    • v.7 no.2
    • /
    • pp.57-84
    • /
    • 2020
  • The Literature Museum Network aims to realize the legislative purpose of the Literature Promotion Act and achieve balanced development of local literature centers across the country. In the Literature Museum Network, the literature museum network support center will be established by region to take charge of cooperation projects between local literature centers, which will be the culmination of the National Literature Museum of Korea. It is intended to test-run various projects planned by the Munhakwan Network Support Center to create derivative contents, or to establish a regional hub literature center in charge of education and other affairs of the literature museum's workforce. If the existing metropolitan administrative districts are used to form zones, the entire country can be organized into four zones. They include the Seoul-Gyeonggi Literature Museum Network (23 local literature centers), the Gangwon Chungcheong Literature Museum Network (32 local literature centers), the Yeongnam Literature Museum Network (30 local literature centers), and the Honam Jeju Literature Museum Network (22 local literature centers). One literature museum network support center will be established for each region and one local literature center will be selected as the hub literature center. The Literature Hall Network Support Center is in charge of collecting and managing literary materials, developing contents and programs, promoting and foreign cooperation, etc. The hub literature museum will be in charge of pilot operation of content and programs, training and education of experts in the literature museum, and running joint storage facilities. This structural system and efficient operation of the literature museum network will ultimately provide an opportunity for the formation of cultural governance in which the power and public nature of the establishment of literary promotion infrastructure are secured.

A Topic Modeling Approach to the Analysis of Happiness Issues Before and After Pandemic (코로나 전후 행복 이슈 변화 분석 및 행복 증진 방안 연구)

  • Kim, Gahye;Lee, So-Hyun
    • Journal of Intelligence and Information Systems
    • /
    • v.28 no.3
    • /
    • pp.81-103
    • /
    • 2022
  • It recognizes the importance of mental health and well-being worldwide and consistently records public happiness figures through the World Happiness Report. COVID-19, which occurred in China in 2019, has changed people's daily lives a lot. The accumulation of stress caused by the prolonged epidemic is affecting people's happiness. The present research has revealed negative mental health effects such as "depression" and "anxiety" after the pandemic. In this regard, it was revealed that the happiness index was also lowered numerically. It is insufficient to analyze specific issues about changes in the issue of happiness felt by the public in Korean society after the epidemic. Therefore, this study aims to identify changes in the happiness issue of Koreans after COVID-19 and find ways to improve happiness. Data were collected from various aspects by searching 32 sub keywords based on ERG theory by dividing the period before and after COVID-19. The results of topic modeling before and after COVID-19 were classified into seven areas of happiness index 2.0 published by the National Assembly Future Research Institute and compared and analyzed. Based on the results of comparing the results of the before and after topic from the perspective of each area, a plan to improve happiness was presented. The academic implications of this paper are that the research on psychological changes caused by COVID-19 was expanded by mining the opinions of the actual public on 'happiness'. In addition, it has practical implications in that it specifically presented measures to promote happiness by utilizing the area of objective happiness indicators based on the existing research on ways to reduce happiness promotion unhappiness.

A Study of Improvements in the Standards of Cost Estimate for the New Excellent Technology in Construction (건설 신기술의 원가산정기준 개선방안에 대한 연구)

  • Lee, Ju-hyun;Tae, Yong-Ho;Baek, Seung-Ho;Kim, Kyoungmin
    • Korean Journal of Construction Engineering and Management
    • /
    • v.23 no.5
    • /
    • pp.65-76
    • /
    • 2022
  • The New Excellent Technology (NET) designation system, introduced in 1989 for the purpose of promoting the development of domestic construction technology and enhancing national competitiveness, reviews the statement of construction cost of new technologies. And the cost reduction effect such as design, construction, and maintenance cost and the effect of reducing the construction duration are evaluated as an evaluation criteria of economic feasibility. However, in this evaluation process, differences of opinion between the institution of construction cost estimating standard management and the new technology developer about unique technologies frequently occur. In addition it is difficult to objectively compare the construction duration with existing similar technologies because there is no information on productivity as the current cost estimating standards for new technologies only present the required amount per unit quantity. In this study, the current state of cost estimating criteria review procedure, evaluation criteria, and cost estimating standards establishment method were analyzed when screening for the designation of a new construction technologies, and compared with overseas cost estimating standards, measures to improve the cost estimating standards of current construction new technologies were suggested. Through the improved cost estimating standards of this study, it is expected that cost information on new technologies will be provided to clients in more detail than the current ones, and the availability and applicability of new construction technologies would be improved by simplifying the construction cost calculation process more.