• Title/Summary/Keyword: earth system science

Search Result 1,599, Processing Time 0.038 seconds

Overview of new developments in satellite geophysics in 'Earth system' research

  • Moon Wooil M.
    • 한국지구물리탐사학회:학술대회논문집
    • /
    • 2004.06a
    • /
    • pp.3-17
    • /
    • 2004
  • Space-borne Earth observation technique is one of the most cost effective and rapidly advancing Earth science research tools today and the potential field and micro-wave radar applications have been leading the discipline. The traditional optical imaging systems including the well known Landsat, NOAA - AVHRR, SPOT, and IKONOS have steadily improved spatial imaging resolution but increasing cloud covers have the major deterrent. The new Earth observation satellites ENVISAT (launched on March 1 2002, specifically for Earth environment observation), ALOS (planned for launching in 2004 - 2005 period and ALOS stands for Advanced Land Observation Satellite), and RADARSAT-II (planned for launching in 2005) all have synthetic aperture radar (SAR) onboard, which all have partial or fully polarimetric imaging capabilities. These new types of polarimetric imaging radars with repeat orbit interferometric capabilities are opening up completely new possibilities in Earth system science research, in addition to the radar altimeter and scatterometer. The main advantage of a SAR system is the all weather imaging capability without Sun light and the newly developed interferometric capabilities, utilizing the phase information in SAR data further extends the observation capabilities of directional surface covers and neotectonic surface displacements. In addition, if one can utilize the newly available multiple frequency polarimetric information, the new generation of space-borne SAR systems is the future research tool for Earth observation and global environmental change monitoring. The potential field strength decreases as a function of the inverse square of the distance between the source and the observation point and geophysicists have traditionally been reluctant to make the potential field observation from any space-borne platforms. However, there have recently been a number of potential field missions such as ASTRID-2, Orsted, CHAMP, GRACE, GOCE. Of course these satellite sensors are most effective for low spatial resolution applications. For similar objects, AMPERE and NPOESS are being planned by the United States and France. The Earth science disciplines which utilize space-borne platforms most are the astronomy and atmospheric science. However in this talk we will focus our discussion on the solid Earth and physical oceanographic applications. The geodynamic applications actively being investigated from various space-borne platforms geological mapping, earthquake and volcano .elated tectonic deformation, generation of p.ecise digital elevation model (DEM), development of multi-temporal differential cross-track SAR interferometry, sea surface wind measurement, tidal flat geomorphology, sea surface wave dynamics, internal waves and high latitude cryogenics including sea ice problems.

  • PDF

A Case Study on the Development of an Elevated Subsidence Inversion Over a Surface Low Pressure System

  • Kim, Kyung-Eak;Ko, Hye-Young;Heo, Bok-Haeng;Ha, Kyung-Ja
    • Journal of the Korean earth science society
    • /
    • v.31 no.5
    • /
    • pp.531-538
    • /
    • 2010
  • This study presents the development of an elevated subsidence inversion over a surface low pressure system, which was formed along the Changma front or Meiu-Baiu front. The results of our analysis strongly suggest that the inversion is dissimilar to those formed in anticyclonic situations but is instead similar to the onion-shaped sounding found in wake low. The present analysis indicates that the observed elevated inversion resulted from the intrusion of stratospheric air associated with tropopause folding.

LOS Analysis Algorithm for Mid-range Guided Weapon System (중거리지대공 유도무기체계 적용을 위한 가시선 분석 알고리듬 연구)

  • Lee, Han-Min
    • Journal of the Korea Institute of Military Science and Technology
    • /
    • v.13 no.4
    • /
    • pp.642-649
    • /
    • 2010
  • LOS analysis is used for optimal deployment of mid-range guided weapon system or system engagement effectiveness simulation. Comparing to real-world, LOS analysis includes error sources such as coarse terrain data resolution, refraction of radio waves, and several ideal assumptions. In this research, exact LOS algorithm under assumption of constant earth curvature and error analysis of that is investigated. It proved that LOS algorithm under assumption of constant earth curvature has negligible error in mid-range guidance weapon system's scope.

Analysis of Secondary School Students' System Thinking on the Cycle of Matter in Earth System: Considering the Impact of Human Activity on the Cycle (지구 시스템 내 물질 순환에 대한 중·고등학교 학생들의 시스템 사고 분석: 인간의 활동이 순환에 미치는 영향을 고려하여)

  • Oh, Hyunseok;Lee, Kiyoung;Kim, Kwonjung
    • Journal of Science Education
    • /
    • v.45 no.3
    • /
    • pp.275-291
    • /
    • 2021
  • The purpose of this study is to analyze the level and characteristics of system thinking of middle and high school students on cycle of matter in the Earth system considering the impact of human activities on the cycle. For this purpose, we developed items for assessment and assessment rubric through the analysis of 2015 revised curriculum and applying systems thinking, respectively. Middle and high school students who participated in the Korea Earth Science Olympiad were the subjects of this study. The level of system thinking was determined using the assessment rubric for student responses collected using items for assessment. The characteristics of system thinking were identified using word analysis. Based on these, the improvement of the curriculum considering the impact of human activities was discussed. The results of the study are as follows: first, the system thinking level of most secondary school students was low in identifying or classifying system elements for matter cycle, and high levels, such as system relationship or generalization of patterns, were found to be relatively small. It was found that students had a higher level of system thinking in the carbon cycle than in the water cycle. Second, in terms of the characteristics of system thinking about water cycle, water was recognized as a major system element and mainly related with evaporation between atmosphere and other system elements. Whereas, in the carbon cycle, carbon dioxide was regarded as a major system element, and photosynthesis and respiration were represented in relation with the biosphere. Third, for education considering the impact of human activities on the matter cycle in the Earth system, it is proposed improving the curriculum considering the socio-ecological system by extending the existing earth system.

Construction of 3D Earth Optical Model for Earth Remote Sensing (Amon-Ra) Instrument at L1 Halo Orbit

  • Ryu, Dong-Ok;Seong, Se-Hyun;Hong, Jin-Suk;Kim, Sug-Whan
    • Bulletin of the Korean Space Science Society
    • /
    • 2011.04a
    • /
    • pp.30.1-30.1
    • /
    • 2011
  • We present construction of 3D Earth optical Model for in-orbit performance prediction of L1 halo orbiting earth remote sensing instrument; the Albedo Monitor and Radiometer (Amon-Ra) using Integrated Ray Tracing (IRT) computational technique. The 3 components are defined in IRT; 1) Sun model, 2) Earth system model (Atmosphere, Land and Ocean), 3)Amon-Ra Instrument model. In this report, constructed sun model has Lambertian scattering hemisphere structure. The atmosphere is composed of 16 distributed structures and each optical model includes scatter model with both reflecting and transmitting direction respond to 5 deg. intervals of azimuth and zenith angles. Land structure model uses coastline and 5 kinds of vegetation distribution data structure, and its non-Lambertian scattering is defined with the semi-empirical "parametric kernel method" used for MODIS (NASA) missions. The ocean model includes sea ice cap with the sea ice area data from NOAA, and sea water optical model which is considering non-Lambertian sun-glint scattering. The IRT computation demonstrate that the designed Amon-Ra optical system satisfies the imaging and radiometric performance requirement. The technical details of the 3D Earth Model, IRT model construction and its computation results are presented together with future-works.

  • PDF

Grazing system and floor type effects on blood biochemistry, growth and carcass characteristics of Nguni goats

  • Chikwanda, Allen Tapiwa;Muchenje, Voster
    • Asian-Australasian Journal of Animal Sciences
    • /
    • v.30 no.9
    • /
    • pp.1253-1260
    • /
    • 2017
  • Objective: Purpose was to determine the effects of grazing system and floor type on concentrations of blood metabolites, activity of creatine kinase, body weight and carcass characteristics of castrated Nguni goats. Methods: Forty eight, 7 month old goats were randomly allocated to herding and tethering treatments from 0800 to 1300 hours and accommodated on slatted and earth floors daily. Blood samples were collected by jugular venipuncture every fifteenth day for metabolite analysis. Slaughter was done at a commercial abattoir following 5 months of monitoring. Results: Tethered goats had significantly higher concentrations of urea (5.19 mmol/L) (p<0.001), creatinine ($55.87{\mu}mol/L$) (p<0.05), total protein (64.60 g/L) (p<0.01), and globulin (49.79 g/L) (p<0.001), whereas herded goats had higher glucose (3.38 mmol/L) (p<0.001), albumin (15.33 g/L) (p<0.05), albumin/globulin ratio (0.34) (p<0.01), and body weight (24.87 kg) (p<0.001). Slatted floors caused higher (p<0.01) albumin at 15.37 g/L. The interaction of grazing system and floor type affected creatinine, total protein, globulin at (p<0.01) and albumen/globulin ratio at (p<0.01). The least creatinine concentration and albumin/globulin ratio was in herded and tethered goats that were accommodated on earth floors, respectively. The highest total protein and globulin concentrations were in serum of tethered goats that were accommodated on earth floors. The highest (p<0.05) dressing percentage (45.26%) was in herded goats accommodated on slatted floors. Conclusion: Herding of goats lowered globulin concentration, improved estimated feed intake, blood glucose and albumin concentrations, albumin globulin ratio, increased body weights and weight related carcass characteristics. Floor type had very little effects on metabolites where earth floors only reduced albumin concentration. Tethering and housing goats on earth floors resulted in double stress that increased chronic infections.

A Survey Study for Establishment of National Global Earth Observation System of Systems (국가 전지구관측시스템 구축을 위한 기초조사연구)

  • Ahn, bu-young;Joh, min-su
    • Proceedings of the Korea Contents Association Conference
    • /
    • 2007.11a
    • /
    • pp.80-83
    • /
    • 2007
  • Entering 21st century, various natural disasters have been caused by the scorching heat wave, earthquake, tsunami, typhoon and so on. The casuality and damages have been drastically increased in terms of the frequency and magnitude. Therefore, 50 nations around the world agreed to build up the GEO(Global Earth Observation) in charge of the earth observation for the understanding of the earth system changes, monitoring and prediction and it is on operation. To keep the pace with GEOSS for the cooperation of Science & Technology and to successfully achieve the GEOSS project, KGEO office was established and has been on its duty. Moreover, for more prosperous building of the GEOSS, in cooperation with KGEO and KISTI(Korea Institute of Science and Technology Information), we've conducted the survey of the domestic situation about 9 societal benefit areas of the GEOSS. This survey consists of 5 sections as follows: the standardization, the information system management, the raw data and metadata, the infrastructure, and the others. This survey results will be used as the basic material for establishing the National Global Earth Observation System.

  • PDF

Determination of dynamic threshold for sea-ice detection through relationship between 11 µm brightness temperature and 11-12 µm brightness temperature difference (11 µm 휘도온도와 11-12 µm 휘도온도차의 상관성 분석을 활용한 해빙탐지 동적임계치 결정)

  • Jin, Donghyun;Lee, Kyeong-Sang;Choi, Sungwon;Seo, Minji;Lee, Darae;Kwon, Chaeyoung;Kim, Honghee;Lee, Eunkyung;Han, Kyung-Soo
    • Korean Journal of Remote Sensing
    • /
    • v.33 no.2
    • /
    • pp.243-248
    • /
    • 2017
  • Sea ice which is an important component of the global climate system is being actively detected by satellite because it have been distributed to polar and high-latitude region. and the sea ice detection method using satellite uses reflectance and temperature data. the sea ice detection method of Moderate-Resolution Imaging Spectroradiometer (MODIS), which is a technique utilizing Ice Surface Temperature (IST) have been utilized by many studies. In this study, we propose a simple and effective method of sea ice detection using the dynamic threshold technique with no IST calculation process. In order to specify the dynamic threshold, pixels with freezing point of MODIS IST of 273.0 K or less were extracted. For the extracted pixels, we analyzed the relationship between MODIS IST, MODIS $11{\mu}m$ channel brightness temperature($T_{11{\mu}m}$) and Brightness Temperature Difference ($BTD:T_{11{\mu}m}-T_{12{\mu}m}$). As a result of the analysis, the relationship between the three values showed a linear characteristic and the threshold value was designated by using this. In the case ofsea ice detection, if $T_{11{\mu}m}$ is below the specified threshold value, it is detected as sea ice on clear sky. And in order to estimate the performance of the proposed sea ice detection method, the accuracy was analyzed using MODIS Sea ice extent and then validation accuracy was higher than 99% in Producer Accuracy (PA).

Detection of Marine Oil Spills from PlanetScope Images Using DeepLabV3+ Model (DeepLabV3+ 모델을 이용한 PlanetScope 영상의 해상 유출유 탐지)

  • Kang, Jonggu;Youn, Youjeong;Kim, Geunah;Park, Ganghyun;Choi, Soyeon;Yang, Chan-Su;Yi, Jonghyuk;Lee, Yangwon
    • Korean Journal of Remote Sensing
    • /
    • v.38 no.6_2
    • /
    • pp.1623-1631
    • /
    • 2022
  • Since oil spills can be a significant threat to the marine ecosystem, it is necessary to obtain information on the current contamination status quickly to minimize the damage. Satellite-based detection of marine oil spills has the advantage of spatiotemporal coverage because it can monitor a wide area compared to aircraft. Due to the recent development of computer vision and deep learning, marine oil spill detection can also be facilitated by deep learning. Unlike the existing studies based on Synthetic Aperture Radar (SAR) images, we conducted a deep learning modeling using PlanetScope optical satellite images. The blind test of the DeepLabV3+ model for oil spill detection showed the performance statistics with an accuracy of 0.885, a precision of 0.888, a recall of 0.886, an F1-score of 0.883, and a Mean Intersection over Union (mIOU) of 0.793.

Anaerobic Mono- and Co-digestion of Primary Sludge, Secondary Sludge and Food Waste: Biogas Production at Different Mixture Ratio (일차슬러지, 이차슬러지 및 음식물류폐기물의 단독 및 통합 혐기성 소화: 혼합비율 차이에 따른 바이오가스 생산량 조사)

  • Seonmin Kang;Minjae Kim;Juyun Lee;Sungyun Jung;Taeyoon Lee;Kwang Hee Nam;Joonyeob Lee
    • Journal of Environmental Science International
    • /
    • v.32 no.1
    • /
    • pp.47-55
    • /
    • 2023
  • This study evaluated the biochemical methane potential (BMP) of primary sludge, secondary sludge, and food waste in batch anaerobic mono-digestion tests, and investigated the effects of mixture ratio of those organic wastes on methane yield and production rate in batch anaerobic co-digestion tests, that were designed based on a simplex mixture design method. The BMP of primary sludge, secondary sludge and food waste were determined as 234.2, 172.7, and 379.1 mL CH4/g COD, respectively. The relationships between the mixing ratio of those organic wastes with methane yield and methane production rate were successfully expressed in special cubic models. Both methane yield and methane production rate were estimated as higher when the mixture ratio of food waste was higher. At a mixing ratio of 0.5 and 0.5 for primary sludge and food waste, the methane yield of 297.9 mL CH4/g COD was expected; this was 19.4% higher than that obtained at a mixing ratio of 0.3333, 0.3333 and 0.3333 for primary sludge, secondary sludge, and food waste (249.5 mL CH4/g COD). These findings could be useful when designing field-scale anaerobic digersters for mono- and co-digestion of sewage sludges and food waste.