• Title/Summary/Keyword: Typhoons

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Standardization Trend and Propulsion Strategy of Wind Power Generation (풍력발전 표준화 동향 및 추진전략)

  • Kim, Mann-eung
    • 한국신재생에너지학회:학술대회논문집
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    • 2009.06a
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    • pp.475-475
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    • 2009
  • Recent alarming acceleration of global warming has made power generations using renewable energy to be in the middle of the spotlight. Korean government has also announced that it will make the related industry to be nation's one of main export items with high investments to low carbon green growth industry. To achieve this goal of exporting the renewable energy power generation system beyond domestic use, internationally acceptable rules should be applied and the three step processes of design, performance assessment and certification should follow international standards. Corresponding this international requests, IEC(International Electrotechnical Commission) is conducting the establishment of rules in TC88 for technical requirements of wind turbines. Design life-time of a wind turbine is required to be at least 20 years. In the meantime, the wind turbine will experience a lot of load cases such as extreme loads and fatigue loads which will include several typhoons per year and extreme gusts with 50 years recurrence period as well as endless turbulence flow. Therefore, IEC 61400-1 specifies design load cases to be considered in the wind turbine design and requires the wind turbine to withstand the load cases in various operational situations. It thus appears that the examination of contents and decisions discussed in the international standard committee will help people in the field of offshore wind energy and ocean energy converters.

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Analysis of Changes in Extreme Weather Events Using Extreme Indices

  • Kim, Byung-Sik;Yoon, Young-Han;Lee, Hyun-Dong
    • Environmental Engineering Research
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    • v.16 no.3
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    • pp.175-183
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    • 2011
  • The climate of the $21^{st}$ century is likely to be significantly different from that of the 20th century because of human-induced climate change. An extreme weather event is defined as a climate phenomenon that has not been observed for the past 30 years and that may have occurred by climate change and climate variability. The abnormal climate change can induce natural disasters such as floods, droughts, typhoons, heavy snow, etc. How will the frequency and intensity of extreme weather events be affected by the global warming change in the $21^{st}$ century? This could be a quite interesting matter of concern to the hydrologists who will forecast the extreme weather events for preventing future natural disasters. In this study, we establish the extreme indices and analyze the trend of extreme weather events using extreme indices estimated from the observed data of 66 stations controlled by the Korea Meteorological Administration (KMA) in Korea. These analyses showed that spatially coherent and statistically significant changes in the extreme events of temperature and rainfall have occurred. Under the global climate change, Korea, unlike in the past, is now being affected by extreme weather events such as heavy rain and abnormal temperatures in addition to changes in climate phenomena.

A Study on the Activation of FM Radio Receive Chip in Smartphone for Disaster Broadcast Reception (재난방송 수신을 위한 스마트폰 FM 라디오 수신 칩 활성화 방안)

  • Shin, Jin-Sik;Bong, Sang-Il;Choi, Seong-Jhin
    • Journal of Satellite, Information and Communications
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    • v.12 no.4
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    • pp.1-10
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    • 2017
  • Sudden natural disasters such as earthquakes, typhoons, heavy rainfall, etc., which come without warning, often threaten our lives and property, so it is important to spread the disaster quickly and accurately. Thus, in this paper, we present a method for the activating of FM radio receiver chip embedded in smartphone to receive disaster broadcasting in case of disaster. One is to investigate the roles and limits in a domestic disaster broadcasting system and disaster relay broadcasting by media, and the other is to present the method for the activation of smartphone FM radio receiver chip by conduct an expert survey.

Characteristics of the Extratropical Transition of Tropical Cyclones over the Western North Pacific using the Cyclone Phase Space (CPS) Diagram (북서태평양에서 저기압 위상 공간도법을 이용한 태풍의 온대저기압화 특성 분석)

  • Lee, Ji-Yun;Park, Jong-Suk;Kang, KiRyong;Chung, Kwan-Young
    • Atmosphere
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    • v.18 no.3
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    • pp.159-169
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    • 2008
  • The characteristics of the typhoon's extratropical transition (ET) over the western North Pacific area were investigated using the cyclone phase space (CPS) diagram method suggested by Hart (2003). The data used in this study were the global data assimilation prediction system (GDAPS) and NCEP data set. The number of typhoons selected were 75 cases during 2002 to 2007, and the three parameters were analyzed : the motion relative thickness asymmetry of the storm (B), the upper thermal wind shear and the lower thermal wind shear. Comparing the best-track data provided by the Regional Specialized Meteorological Center /Tokyo, the time of the ET based on CPS was 2~6 hours earlier than the best-track data. And it was shown that the 400- km and 30 kt wind radius of storm for the CPS method were better agreement than the previous suggested radius 500- km.

Optimal reduction from an initial sensor deployment along the deck of a cable-stayed bridge

  • Casciati, F.;Casciati, S.;Elia, L.;Faravelli, L.
    • Smart Structures and Systems
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    • v.17 no.3
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    • pp.523-539
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    • 2016
  • The ambient vibration measurement is an output-data-only dynamic testing where natural excitations are represented, for instance, by winds and typhoons. The modal identification involving output-only measurements requires the use of specific modal identification techniques. This paper presents the application of a reliable method (the Stochastic Subspace Identification - SSI) implemented in a general purpose software. As a criterion toward the robustness of identified modes, a bio-inspired optimization algorithm, with a highly nonlinear objective function, is introduced in order to find the optimal deployment of a reduced number of sensors across a large civil engineering structure for the validation of its modal identification. The Ting Kau Bridge (TKB), one of the longest cable-stayed bridges situated in Hong Kong, is chosen as a case study. The results show that the proposed method catches eigenvalues and eigenvectors even for a reduced number of sensors, without any significant loss of accuracy.

On Statistical Properties of the Extreme Waves in Hong-do Sea Area During Typhoons (홍도 해역에서 태풍 중 극한파의 통계적 특성에 대한 연구)

  • Ryu Hwanajin;Kim Do Young
    • Journal of the Korean Society for Marine Environment & Energy
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    • v.7 no.1
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    • pp.47-55
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    • 2004
  • In this paper, The statistical properties of ocean waves in the sea area of Hong-do, Korea are examined based on 1998-2002's wave data from a directional wave buoy. Wave data aquisition rate, mean wave heights, frequency of wave direction are summarized. Wave height and period scatter diagrams and n-year return period wave heights are estimated. Wave periods of maximum wave heights are also estimated. Large amplitude wave characteristics during the typhoon Prapiroon in 2000, Rusa in 2002 are also examined.

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Occurrence Characteristics of Marine Accidents Caused by Typhoon (태풍에 의한 해양사고의 발생 특성)

  • Yang Chan-Su
    • Proceedings of KOSOMES biannual meeting
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    • 2004.05b
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    • pp.53-56
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    • 2004
  • During the period of every summer to early autumn seasons, ships have been wrecked or grounded from effect of a typhoon in the water areas around Korean Peninsular. Typhoon Maemi. which brushed South Korea in September 12-13, 2003, left at least 110 dead or missing, knocking down building. smashing ships and triggering floods that forced about 25,000 to flee from their homes. In this work. records .of marine accidents caused by a typhoon are investigated for the period from 1962-2002. The distribution is also compared with the trajectories of typhoons, passed during the 1990-2003. In addition to that, attack frequency of typhoon and number of marine accidents is the highest in August

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Analysis of Typhoon Storm Occurrence and Runoff Characteristics by Typhoon Tracks in Nakdong River Basin (낙동강유역의 태풍경로별 호우발생특성 및 유출특성 분석)

  • 한승섭
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.38 no.5
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    • pp.64-73
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    • 1996
  • When typhoon occurs, the meteorological conditions get worse and can cause a large damage from storm and flood . This damage, however, can be minimized if a precise analysis of the runoff characteristics by typhoon tracks is used in the flood contorl This paper aims at the analysis of storm occurrence and runoff characteristics by typhoon tracks in Nakdong river basin. Therefore, the data of 14 typhoons which invaded Nakdong river basin during the period from 1975 to 1991 were collected, analyzed, and studied. The major results of this study are as followings; 1) The frequency of the typhoon occurrence here in Korea was affected by the storms three times a year on the average. The highest-recorded frequency was during the months of July to September. 2) The survey of the track characteristics depending on the forms of the storm in the Nakdong river basin showed that typhoon storm advanced from the south of the basin to the north, while the frontal type storm was most likely to advanced from the west to the north. 3) Typhoon tracks are classified into three categories, 6 predictors with high correlation coefficient are finally selected, and stepwise multiple regression method are used to establish typhoon strom forecasting models. 4) The riview on the directions of progress of the storm made it clear that the storm moving downstream from upstream of the basin could develop into peak discharge for ca short time and lead to more flood damage than in any other direction.

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Fundamental Study about GIS Information Construction of Seashore Structure (해안구조물의 GIS정보 구축을 위한 기초연구)

  • Han, seung-hee
    • Proceedings of the Korea Contents Association Conference
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    • 2009.05a
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    • pp.481-484
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    • 2009
  • It has been reported that reckless marine structures located in the coastal zone deteriorate environment and tourism due to industrialization and tourist development. Therefore, it needs to analyze am appropriate remodeling plan for environment, tourism, and safety in current marine structures and then establish the standard for the optimum remodeling design and the guidance for maintenance. Furthermore, it needs a precise simulation program about typhoons and tidal waves for the environment, safety and a three-dimensional positioning and structural modeling currently built in structures. This research has a purpose of suggesting a theoretical method for the establishment of GIS information.

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PACIFIC EXTREME WIND AND WAVE CONDITIONS OBSERVED BY SYNTHETIC APERTURE RADAR

  • Lehner, Susanne;Reppucci, Antonio;Schulz-Stellenfleth, Johannes;Yang, Chang-Su
    • Proceedings of the KSRS Conference
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    • v.1
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    • pp.390-393
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    • 2006
  • It is well known that synthetic aperture radar (SAR) provides information on ocean winds and surface waves. SAR data are of particularly high value in extreme weather conditions, as radar is able to penetrate the clouds providing information on different ocean surface processes. In this presentation some recent results on SAR observation of extreme wind and ocean wave conditions is summarised. Particular emphasize is put on the investigation of typhoons and extratropical cyclones in the North Pacific. The study is based on the use of ENVISAT ASAR wide swath images. Wide swath and scansar data are well suited for a detailed investigation of cyclones. Several examples like, e.g., typhoon Talim will be presented, demonstrating that these data provide valuable information on the two dimensional structure of the both the wind and the ocean wave field. Comparisons of the SAR observation with parametric and numerical model data will be discussed. Some limitations of standard imaging models like, e.g., CMOD5 for the use in extreme wind conditions are explained and modifications are proposed. Finally the study summarizes the capabilities of new high resolution TerraSAR-X mission to be launched in October 2006 with respect to the monitoring of extreme weather conditions. The mission will provide a spatialresolution up to 1m and has full polarimetric capabilities.

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