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41.
Jae-Hyun Lim Seunghyun Son Jung-Woo Park Jung Hyun Kwak Chang-Keun Kang Young Baek Son Jung-No Kwon Sang Heon Lee 《Ocean Science Journal》2012,47(3):377-385
The high primary production enhanced by anticyclonic eddies and hourly variation pattern in the productivity during the spring season in the East Sea were first investigated using the first Korean Geostationary Ocean Color Imager (GOCI). Even though the stratification for a seasonal spring bloom is not well developed in the water column in early April in the East Sea, a physical upward water flux movement at the periphery of the anticyclonic eddies could remain the phytoplankton in euphotic zone to sustain high chlorophyll-a concentration conditions in the Ulleung Basin. At this time, nutrients were no major controlling factor for phytoplankton growth since concentrations of major nutrients (nitrate, silicate, and phosphate) were relatively high in the observed eddy sites based on the observation data from the Korean Oceanographic Data Center (KODC). The estimated mixed layer depth (MLD) significantly shallower at the periphery supports for this mechanism. The hourly primary productivity estimation based on a Carbon-based Productivity Model (CbPM) provides a bimodal pattern along the time especially in L1 with an approximately one order magnitude difference between the lowest and highest values of productivities on 5 April, 2011. Potential possibilities for this large discrepancy in the hourly productivity and some thoughts on a short time in situ incubation method were discussed. 相似文献
42.
Detecting massive green algae (Ulva prolifera) blooms in the Yellow Sea and East China Sea using Geostationary Ocean Color Imager (GOCI) data 总被引：2，自引：0，他引：2
The historically massive bloom of the green macroalgae Ulva prolifera reported in June?CAugust 2008 around the Qingdao, Yellow Sea, East China Sea and Japan coasts has recurred in a similar season and region. On June 13, 2011, around Qingdao, China, the world??s first Geostationary Ocean Color Imager (GOCI) detected an enormous bloom of floating green algae, which originated from the nearshore Subei Bank, China. The large floating green algae patches were observed along and across the Yellow Sea and in the East China Sea during 2011 summer by various oceanic cruises. To detect the massive macroalgae blooms from space, we analyzed their spectral characteristics from in situ optical measurements and satellite-derived green algae spectra. An ??Index of floating Green Algae for GOCI?? (IGAG) was developed from the multiple spectral band ratios using three wavelengths (555, 660, 745 nm), which the spectral response of green algae reflected at 555, 745, and 865 nm and absorbed at 660 and 680 nm. The results were compared with those obtained by the normalized difference vegetation index (NDVI), enhanced vegetation index (EVI), and Korea Ocean Satellite Center (KOSC) approaches. An advantage of the IGAG method was that muted or subtle signals of floating green algae were enhanced and separated from surrounding complex water signals. Although maps of floating green algae derived by the other approaches delineated dense green algae, they were less sensitive to subtle (less dense) features and in cases of nearby cloudy or complex water conditions. The floating green algae maps from IGAG provided a more robust estimate of wide floating green algae blooms than those derived using NDVI, EVI, or KOSC approaches. The IGAG approach should be useful for tracing and monitoring changes in green algae blooms on regional and global scales. 相似文献
43.
Lee Jong-Seok Baek Ji-Yeon Jung Dawoon Shim Jae-Seol Lim Hak-Soo Jo Young-Heon 《Ocean Science Journal》2019,54(3):349-362
Ocean Science Journal - Observing coastal water depths is very important to understand physical processes of the coastal environment and manage coastal resources. In this study, a low-altitude... 相似文献
44.
Myung-Seo Koo Sunghye Baek Kyung-Hee Seol Kyoungmi Cho 《Asia-Pacific Journal of Atmospheric Sciences》2017,53(3):361-373
As of 2013, the Noah Land Surface Model (LSM) version 2.7.1 was implemented in a new global model being developed at the Korea Institute of Atmospheric Prediction Systems (KIAPS). This land surface scheme is further refined in two aspects, by adding new physical processes and by updating surface input parameters. Thus, the treatment of glacier land, sea ice, and snow cover are addressed more realistically. Inconsistencies in the amount of absorbed solar flux at ground level by the land surface and radiative processes are rectified. In addition, new parameters are available by using 1-km land cover data, which had usually not been possible at a global scale. Land surface albedo/emissivity climatology is newly created using Moderate-Resolution Imaging Spectroradiometer (MODIS) satellitebased data and adjusted parameterization. These updates have been applied to the KIAPS-developed model and generally provide a positive impact on near-surface weather forecasting. 相似文献
45.
The Government of Botswana has pledged a nationally determined contribution (NDC) as a commitment to the Paris Agreement. For the power sector, the NDC states that the government expects renewable energy (RE) to meet 25% of peak electricity demand by 2030. However, due to high initial cost of RE technologies, the government plans to maintain a coal-based power system in the future. Therefore, the purpose of this paper is to examine Botswana’s national plan from an economic perspective, using scenario and cost analysis, to explore the possibility of the power sector’s low carbon transition in the light of Botswana’s NDC. Five scenarios are designed to reflect a range of investment cost changes of RE technologies. While most scenarios only achieve 19% (P3, P4 and P5) and 54% (P6) of the NDC’s power sector target, the P7 scenario far exceeds the goal by achieving 188% of the NDC target. Furthermore, as the difference of levelized cost of electricity among the scenarios is minimal, the P7 scenario is the most attractive pathway for the government. Even for other scenarios, the government should still deploy the suggested capacity of solar photovoltaic (PV) as it is both economically and socially beneficial in the long term. However, in these cases, the government’s political will to meet the NDC’s power sector target and to promote the solar PV industry will be critical in designing future power sector policies.
Key policy insights
Model results show coal as the cheapest resource for electricity generation in Botswana up to 2030, but the cost competitiveness of solar photovoltaic (PV) against coal will continue to increase over time.
It is economically and socially beneficial to adjust the current national plan and substitute some share of coal with solar PV in the future energy mix.
Government support is critical in achieving the power sector’s NDC target, as cost reduction of solar PV alone does not guarantee success.
Encouraging independent power producers (IPP) with financial support mechanisms would be a suitable business model for developing the renewable energy industry.
46.
Shin Gyu-Beom Jo Bum-Hee Kim Sung-Ryul Baek Sung-Ha Chung Choong-Ki 《Acta Geotechnica》2022,17(9):4173-4190
Acta Geotechnica - This paper presents a finite element model for a load distributive compression anchor (LDCA). In an LDCA, the load applied to the strands is transmitted to the grout and ground... 相似文献
47.
Jeong?Hwan?LeeEmail author Young?Soon?Baek Byong?Jae?Ryu Michael?Riedel Roy?D.?Hyndman 《Marine Geophysical Researches》2005,26(1):51-59
Recently, several countries have conducted projects to explore and develop natural gas hydrate, which is one of the new alternative
energy resources for the future. In Korea, a five-year national research project was initiated in 2000. As part of this project,
a seismic survey was performed in the East Sea of Korea to quantify the potential magnitude and distribution of natural gas
hydrates. Multi-channel seismic data and core samples have been acquired and recovered in the survey area. Analysis of seismic
data show clear bottom simulating reflectors (BSRs), seismic blank zones (or wipe-out zones) with velocity pull-up structure,
and pock-marks. In this study, we present the results of seismic surveys which indicate the existence of natural gas hydrates
in Korean offshore areas. These results will be applied to select areas for coring (or drilling) and detailed exploration
such as 2D seismic survey with long offset or 3D seismic in the future. 相似文献
48.
Using 8-10-m class telescopes and their Adaptive Optics (AO) systems, we conducted a long-term adaptive optics campaign initiated in 2003 focusing on four binary asteroid systems: (130) Elektra, (283) Emma, (379) Huenna, and (3749) Balam. The analysis of these data confirms the presence of their asteroidal satellite. We did not detect any additional satellite around these systems even though we have the capability of detecting a loosely-bound fragment (located at 1/4×RHill) ∼40 times smaller in diameter than the primary. The orbits derived for their satellites display significant eccentricity, ranging from 0.1 to 0.9, suggesting a different origin. Based on AO size estimate, we show that (130) Elektra and (283) Emma, G-type and P-type asteroids, respectively, have a significant porosity (30-60% considering CI-CO meteorites as analogs) and their satellite's eccentricities (e∼0.1) are possibly due to excitation by tidal effects. (379) Huenna and (3749) Balam, two loosely bound binary systems, are most likely formed by mutual capture. (3749) Balam's possible high bulk density is similar to (433) Eros, another S-type asteroid, and should be poorly fractured as well. (379) Huenna seems to display both characteristics: the moonlet orbits far away from the primary in term of stability (20%×RHill), but the primary's porosity is significant (30-60%). 相似文献
49.
Ji-Yeon Park Sang-Joon Kim You-Jin Lee Kitae Baek Ji-Won Yang 《Engineering Geology》2005,77(3-4):217-224
Feasibility of electrokinetic (EK) process combined with Fenton-like reaction was investigated for the removal of phenanthrene in a two-dimensional cell. Sandy soil and bentonite were selected as a model soil and a filling material to inhibit the leak of electrolyte solution within the electrode reservoirs into the soil by hydraulic pressure difference, respectively. The effects of parameters including current, electroosmotic flow (EOF), electrolyte pH, and moisture content on the removal efficiency were examined under constant voltage.
At the end of operation for 21 days, the concentration of phenanthrene near the anode was lower than the other positions of soil specimen and increased gradually towards the cathode because hydrogen peroxide solution was supplied from anode to cathode region following the direction of EOF. The concentration of phenanthrene at the bottom soil was lower than that at the top soil. Because capillary attraction in the sandy soil with high porosity was too low to maintain appropriate moisture at the top of the cell, EOF moved through the bottom soil with higher moisture content. Overall removal efficiency at 140 V was 81.6%, which was higher than 68.9% at 100 V because total EOF increased by a factor of 1.5 upon increase of the voltage from 100 to 140 V. In addition, power consumptions at 100 and 140 V were 7.2 and 19.4 kWh, respectively. 相似文献
50.
Sangho Baek Oh-Ig Kwoun Braun A. Zhong Lu Shum C.K. 《Geoscience and Remote Sensing Letters, IEEE》2005,2(4):413-417
We present a digital elevation model (DEM) of King Edward VII Peninsula, Sulzberger Bay, West Antarctica, developed using 12 European Remote Sensing (ERS) synthetic aperture radar (SAR) scenes and 24 Ice, Cloud, and land Elevation Satellite (ICESat) laser altimetry profiles. We employ differential interferograms from the ERS tandem mission SAR scenes acquired in the austral fall of 1996, and four selected ICESat laser altimetry profiles acquired in the austral fall of 2004, as ground control points (GCPs) to construct an improved geocentric 60-m resolution DEM over the grounded ice region. We then extend the DEM to include two ice shelves using ICESat profiles via Kriging. Twenty additional ICESat profiles acquired in 2003-2004 are used to assess the accuracy of the DEM. After accounting for radar penetration depth and predicted surface changes, including effects due to ice mass balance, solid Earth tides, and glacial isostatic adjustment, in part to account for the eight-year data acquisition discrepancy, the resulting difference between the DEM and ICESat profiles is -0.57/spl plusmn/5.88 m. After removing the discrepancy between the DEM and ICESat profiles for a final combined DEM using a bicubic spline, the overall difference is 0.05/spl plusmn/1.35 m. 相似文献