22 research outputs found
Vulnerability Assessment On Water Management For Climate Change Adaptation : Case Study To Gochang County In South Korea
Currently, 1.6 billion people live in countries and regions with absolute water scarcity and the number is expected to rise to 2.8 billion people by 2025(World Bank). Climate change will make water security more difficult and costly to achieve. Smart Water Management of water resources using an integrated approach with IT (Information Technology) will play a critical role in adapting climate change and mitigate social, economic and environmental impacts. Gochang County in Jeonbuk Province (South Korea) is one of the vulnerable areas to climate change, because it is a particularly high dependency to agricultural industry, increasing proportion of elderly people, and coastal areas where vulnerable to increases in the intensity of storm surge and heavy precipitation. The study mainly utilized the vulnerability definition adopted by IPCC that is a function of exposure, sensitivity and adaptive capacity. This study seeks to investigate the current (2000-2010) risks and vulnerability to flood and drought and those in the future (2046~2055) due to climate change. This study employs proxy indicators to measure the exposure, sensitivity and adaptive capacity. The RCP(Representative Concentration Pathways) 8.5 climate change scenario from KMA (Korea Meteorological Administration) was used and a detailed climate change scenario was compiled with administrative district-level and watershed level for spatial analysis. The climate exposure for the flood vulnerability showed that East Gochang area was more vulnerable than West in the current period. However, in the future period, South Gochang area is potentially most vulnerable than others to climate exposure. The climate exposure for the drought vulnerability showed that North Gochang area was most vulnerable than others in the future period. The results of the vulnerability assessment could be used for the taking measures for climate change adaptation and determining the priority area
Effect of Benthic Flux on the Nutrient Dynamics of Bottom Water during Stratification in an Artificial Brackish Lake
In semi-closed coastal brackish systems, the stratification of the water column due to the interaction between freshwater and seawater can lead to a reduction in the dissolved oxygen (DO) levels in the bottom layers, consequently affecting the benthic nutrient flux and causing the degradation in water quality. We performed in situ investigations using a benthic lander to examine changes in the sediment oxygen demand (SOD) and benthic nutrient flux during the development of stratification in the downstream area of an artificially constructed brackish lake. During each measurement period, the temperature and salinity of the water column showed vertically stable stratification. The potential energy anomaly was 88.1–125.7 J/m3, with the stratification intensity strengthening gradually over the measurement period. The concentration of DO in bottom waters gradually decreased as the stratification of the water intensified and the temperature increased, establishing hypoxic conditions. As the stratification intensified, the SOD decreased with the DO concentration in bottom waters, while the benthic fluxes of NH4-N and PO4-P exhibited an opposite effect. When the effect of offshore water (introduced through a sluice gate) was insignificant, the SOD contributed 33% of the net loss of DO below the pycnocline. During this period, the benthic NH4-N and PO4-P fluxes were estimated to contribute 55% and 87% to the net fluxes in NH4-N and PO4-P, respectively, in the water column below the pycnocline. The benthic NH4-N and PO4-P fluxes resulted in excess phosphorus in the bottom water. When the inflow of seawater through the sluice gate was sufficient, the flow in the upstream direction of the bottom layer moved phosphorus-rich bottom water downstream, which is important for algal growth in the middle-upstream region
Fabrication of Tungsten Oxide Nanowalls through HFCVD for Improved Electrochemical Detection of Methylamine
In this study, well-defined tungsten oxide (WO3) nanowall (NW) thin films were synthesized via a controlled hot filament chemical vapor deposition (HFCVD) technique and applied for electrochemical detection of methylamine toxic substances. Herein, for the thin-film growth by HFCVD, the temperature of tungsten (W) wire was held constant at ~1450 °C and gasification was performed by heating of W wire using varied substrate temperatures ranging from 350 °C to 450 °C. At an optimized growth temperature of 400 °C, well-defined and extremely dense WO3 nanowall-like structures were developed on a Si substrate. Structural, crystallographic, and compositional characterizations confirmed that the deposited WO3 thin films possessed monoclinic crystal structures of high crystal quality. For electrochemical sensing applications, WO3 NW thin film was used as an electrode, and cyclic voltammetry (CV) and linear sweep voltammetry (LSV) were measured with a wide concentration range of 20 μM~1 mM of methylamine. The fabricated electrochemical sensor achieved a sensitivity of ~183.65 μA mM−1 cm−2, a limit of detection (LOD) of ~20 μM and a quick response time of 10 s. Thus, the fabricated electrochemical sensor exhibited promising detection of methylamine with considerable stability and reproducibility
Characterization and application of electrospun alumina nanofibers
Alumina nanofibers were prepared by a technique that combined the sol–gel and electrospinning methods. The solution to be electrospun was prepared by mixing aluminum isopropoxide (AIP) in ethanol, which was then refluxed in the presence of an acid catalyst and polyvinylpyrolidone (PVP) in ethanol. The characterization results showed that alumina nanofibers with diameters in the range of 102 to 378 nm were successfully prepared. On the basis of the results of the XRD and FT-IR, the alumina nanofibers calcined at 1,100°C were identified as comprising the α-alumina phase, and a series of phase transitions such as boehmite → γ-alumina → α-alumina were observed from 500°C to 1,200°C. The pore size of the obtained γ-alumina nanofibers is approximately 8 nm, and it means that they are mesoporous materials. The kinetic study demonstrated that MO adsorption on alumina nanofibers can be seen that the pseudo-second-order kinetic model fits better than the pseudo-first-order kinetic model
Clinical outcomes and costs of robotic surgery in prostate cancer: a multiinstitutional study in Korea
Background: This study compared the surgical, functional, and oncologic outcomes of robot-assisted laparoscopic radical prostatectomy (RALP), laparoscopic radical prostatectomy (LRP), and retropubic radical prostatectomy (RRP) in Korean men. Methods: The study population included 864 patients who underwent radical prostatectomy for prostate cancer in the departments of urology of five tertiary hospitals between 2010 and 2011. RALP, LRP, and RRP perioperative, oncological, and functional outcomes as well as complications were assessed. Medical cost data were analyzed for 682 of 864 patients. Results: No significant differences were found among the three groups regarding the length of stay, biochemical recurrence, complications, and metastasis. The RALP group had a significantly higher rate of pelvic lymph node dissection (64.6% vs. 35.3% or 53.3%, P value <0.0001) and bilateral nerve-sparing procedures (15.7% vs. 10.0% or 8.9%, P value <0.0001) and less blood loss (median 250Â mL vs. 300Â mL or 700Â mL, P value <0.0001) than the LRP and RRP groups. The 12-month continence recovery rate was higher in the RALP group (92.1%) than in the LRP (86.5%) and RRP (84.4%) groups (P value <0.0001). Medical costs for RALP were approximately twofold to threefold higher than those for LRP or RRP. Conclusions: Our findings suggest that surgical and functional outcomes are better with robot-assisted surgery than with laparoscopic or open surgery in terms of estimated blood loss and urinary continence; however, no differences were found among groups in terms of biochemical recurrence and the rate of complications. Keywords: Laparoscopic prostatectomy, Prostate cancer, Radical prostatectomy, Robotic prostatectomy, Robotic surger