• Journal of Energy Engineering
• /
• v.24 no.4
• /
• pp.200-210
• /
• 2015

The modeling for fast pyrolysis of biomass in fluidized bed reactor has been developed for accurate prediction of bio-oil and gas products and for yield improvement. The purpose of this study is to analyze and to compare the CFD(Computational Fluid Dynamics) simulation results with the experimental data from the CFD simulation results with the experimental data from the reference(Mellin et al., 2014) for gas products generated during fast pyrolysis of biomass in fluidized bed reactor. CFD(ANSYS FLUENT v.15.0) was used for the simulation. Complex pyrolysis reaction scheme of biomass subcomponents was applied for the simulation of pyrolysis reaction. This pyrolysis reaction scheme was included reaction of cellulose, hemicellulose, lignin in detail, gas products obtained from pyrolysis were mainly $CO_2$, CO, $CH_4$, $H_2$, $C_2H_4$. The deviation between the simulation results from this study and experimental data from the reference was calculated about 3.7%p, 4.6%p, 3.9%p for $CH_4$, $H_2$, $C_2H_4$ respectively, whereas 9.6%p and 6.7%p for $CO_2$ and CO which are relatively high. Through this study, it is possible to predict gas products accurately by using CFD simulation approach. Moreover, this modeling approach should be developed to predict fluidized bed reactor performance and other gas product yields.

• Journal of the East Asian Society of Dietary Life
• /
• v.20 no.1
• /
• pp.20-29
• /
• 2010

Naringin has antioxidant and antihyperlipidemic properties, however, phenolic compounds including naringin are unstable in the presence of light, heat and oxygen. Beta-cyclodextrin ($\beta$-CD) is a cyclic heptamer composed of seven glucose units that enhances the stability and solubility of molecules through the formation of inclusion complexes. This study was conducted out to compare the effects of CD-naringin (CD-N) inclusion complexes with naringin on lipid metabolism in high fat-fed animals. Male C57BL/6 mice were fed either CD-N (0.048%, w/w) or naringin (N, 0.02%, w/w) in a 20% high-fat (HFC, 15% lard, 5% corn oil, w/w) diet for 10 weeks. Orlistat (Xenical, 0.01%, w/w) was used as a positive control (PC). There were no differences in body weight, food intake, liver and heart weights, plasma triglyceride(TG), leptin, adiponectin, resistin, IL-$1{\beta}$ and IL-6 concentrations, and hepatic $\beta$-oxidation, carnitine palmitoyl transferase(CPT), glucose-6-phosphate dehydrogenase (G6PD) and malic enzyme activities between the HFC and CD-N groups or between the HFC and N groups. However, both CD-naringin and naringin supplementation les to a significant reduction in the epididymal and perirenal white adipose tissue weights, plasma free fatty acid, insulin and blood glucose concentrations, hepatic cholesterol and TG contents and hepatic fatty acid synthase (FAS), phosphatidate phosphohydrolase (PAP) and HMG-CoA reductase activities compared to the HFC group. The plasma HDL-cholesterol concentration was significantly higher in CD-N and N groups than in HF and PC groups. These results indicate that both CD-naringin and naringin supplementation effectively improved plasma and hepatic lipid metabolism without differences between CD-N and naringin groups.

• The Journal of Engineering Geology
• /
• v.16 no.1 s.47
• /
• pp.69-83
• /
• 2006

This study aims to evaluate a complex groundwater flow system around the underground oil storage caverns using the concept of hydraulic compartment. For the hydrogeological analysis, the hydraulic testing data, the evolution of groundwater levels in 28 surface monitoring boreholes and pressure variation of 95 horizontal and 63 vertical water curtain holes in the caverns were utilized. At the cavern level, the Hydraulic Conductor Domains(fracture zones) are characterized one local major fracture zone(NE-1)and two local fracture zones between the FZ-1 and FZ-2 fracture zones. The Hydraulic Rock Domain(rock mass) is divided into four compartments by the above local fracture zones. Two Hydraulic Rock Domains(A, B) around the FZ-2 zone have a relatively high initial groundwater pressures up to $15kg/cm^2$ and the differences between the upper and lower groundwater levels, measured from the monitoring holes equipped with double completion, are in the range of 10 and 40 m throughout the construction stage, indicating relatively good hydraulic connection between the near surface and bedrock groundwater systems. On the other hand, two Hydraulic Rock Domains(C, D) adjacent to the FZ-1, the groundwater levels in the upper and lower zones are shown a great difference in the maximum of 120 m and the high water levels in the upper groundwater system were not varied during the construction stage. This might be resulted from the very low hydraulic conductivity$(7.2X10^{-10}m/sec)$ in the zone, six times lower than that of Domain C, D. Groundwater recharge rates obtained from the numerical modeling are 2% of the annual mean precipitation(1,356mm/year) for 20 years.

• Korean Journal of Heritage: History & Science
• /
• v.56 no.3
• /
• pp.138-156
• /
• 2023

Some of the metal cultural heritage that make up a considerable proportion of Korea's cultural heritage have been installed and displayed outdoors due to their own functions, roles, and scale. Therefore, more diverse and complex damages can occur outdoors than they are in a stable environment. Therefore, it is necessary to combine accurate diagnosis and systematic survey methods in order to utilize basic data obtained from research results as data for the long-term and continuous conservation management as well as to do the research to diagnose the conservation status of outdoor cultural heritage. The clepsydra(hereinafter referred to as Jagyeongnu) of Changgyeonggung Palace, the National Treasure has been installed and displayed outdoors since it was manufactured. Though regular conservation and maintenance of the Jagyeongnu have been carried out, damage still occurred. Therefore, the scientific research on Jagyeongnu to diagnose the state of conservation was conducted prior to the full-scale conservation treatment. First, the state of conservation was investigated with an examination of basic data, macroscopic inspections and past records of repair history according to the purpose of the research. More detailed examinations were also conducted through the 3D scan, surface pattern investigation, and color difference analysis, and the analysis on materials and contaminants were conducted through P-XRF, FT-IR, and Py-GC/MS. The scientific research reveals that squalane and silicone oil have been applied in the past for conservation treatment and directly exposed to outdoor environmental factors, which caused damage to Jagyeongnu and contaminants such as dust adhered thickly to its surface, accelerating severe damage. A greater incidence of damage was found around the part with relatively high exposure effect, which corresponded with the tendency identified by grouping color difference data. As a result of integrating various research methodologies to diagnose the state of conservation and secure basic data, the causes and types of damage were identified. Furthermore, the process of obtaining digital data to be utilized in various ways, and the color difference analysis presenting visible damage as scientific data and identifying the tendency of damage patterns were confirmed to have been effective.

• Journal of the Korean earth science society
• /
• v.45 no.2
• /
• pp.136-146
• /
• 2024

This paper introduces the seismic facies classification and mapping of igneous bodies found in the sedimentary sequences of the Yellow Sea shelf area of Korea. In the research area, six extrusive and three intrusive types of igneous bodies were found in the Late Cretaceous, Eocene, Early Miocene, and Quaternary sedimentary sequences of the northeastern, southwestern and southeastern sags of the Gunsan Basin. Extrusive igneous bodies include the following six facies: (1) monogenetic volcano (E.mono) showing cone-shape external geometry with height less than 200 m, which may have originated from a single monogenetic eruption; (2) complex volcano (E.comp) marked by clustered monogenetic cones with height less than 500 m; (3) stratovolcano (E.strato) referring to internally stratified lofty volcanic edifices with height greater than 1 km and diameter more than 15 km; (4) fissure volcanics (E.fissure) marked by high-amplitude and discontinuous reflectors in association with normal faults that cut the acoustic basement; (5) maar-diatreme (E.maar) referring to gentle-sloped low-profile volcanic edifices with less than 2 km-wide vent-shape zones inside; and (6) hydrothermal vents (E.vent) marked by upright pipe-shape or funnel-shape structures disturbing sedimentary sequence with diameter less than 2 km. Intrusive igneous bodies include the following three facies: (1) dike and sill (I.dike/sill) showing variable horizontal, step-wise, or saucer-shaped intrusive geometries; (2) stock (I.stock) marked by pillar- or horn-shaped bodies with a kilometer-wide intrusion diameter; and (3) batholith and laccoliths (I.batho/lac) which refer to gigantic intrusive bodies that broadly deformed the overlying sedimentary sequence.

• Geophysics and Geophysical Exploration
• /
• v.13 no.1
• /
• pp.24-30
• /
• 2010

This study utilises repeated numerical tests to understand the effects of variable near-surface conditions on time-lapse seismic surveys. The numerical tests were aimed at reproducing the significant scattering observed in field experiments conducted at the Naylor site in the Otway Basin for the purpose of $CO_2$ sequestration. In particular, the variation of elastic properties of both the top soil and the deeper rugose clay/limestone interface as a function of varying water saturation were investigated. Such tests simulate the measurements conducted in dry and wet seasons and to evaluate the contribution of these seasonal variations to seismic measurements in terms of non-repeatability. Full elastic pre-stack modelling experiments were carried out to quantify these effects and evaluate their individual contributions. The results show that the relatively simple scattering effects of the corrugated near-surface clay/limestone interface can have a profound effect on time-lapse surveys. The experiments also show that the changes in top soil saturation could potentially affect seismic signature even more than the corrugated deeper surface. Overall agreement between numerically predicted and in situ measured normalised root-mean-square (NRMS) differences between repeated (time-lapse) 2D seismic surveys warrant further investigation. Future field studies will include in situ measurements of the elastic properties of the weathered zone through the use of 'micro Vertical Seismic Profiling (VSP)' arrays and very dense refraction surveys. The results of this work may impact on other areas not associated with $CO_2$ sequestration, such as imaging oil production over areas where producing fields suffer from a karstic topography, such as in the Middle East and Australia.

• Journal of Environmental Science International
• /
• v.17 no.4
• /
• pp.423-437
• /
• 2008

Until comparatively lately, the annual time series of the $SO_2$ concentration had been shown in a decreasing trend in Ulsan as well as other Korean cities. However, the high concentration of $SO_2$ was frequently found in the specific countermeasure region including the national industrial complex such as Mipo and Onsan in the Ulsan city for the period of $2001{\sim}2004$. There are many conditions that can influence the high concentration of $SO_2$ at monitoring sites in Ulsan, such as: First, annual usage of the fuel including sulfur increased in comparison with the year before in spite of the fuel conversion policy which wants to use low sulfur oil less than 3% and LNG. Second, point source, such as the power plants and the petroleum and chemistry stacks, was the biggest contributor in $SO_2$ emission, as a analyzed result of both the air quality modeling and the stack tole-monitoring system (TMS) data. And third, the air pollutants that occurred in processes of homing and manufacturing of the fuel including sulfur were transported slow into a special monitoring site by accumulating along the frontal area of see-breeze. It was concluded that Ulsan's current environmental policy together with control methods should be changed into the regulation on total amount of emission, including a market-based emission trading with calculating of atmospheric environmental critical loads, for the $SO_2$ reduction like the specific countermeasure for the $O_3$ and PM10 reduction in the Seoul metropolitan area. And this change should be started in the big point sources of $1{\sim}3$ species because they are big contributors of Ulsan's $SO_2$ pollution. Especially it is necessary to revitalize of the self-regulation environmental management. Other control methods for sustaining the $SO_2$ reduction are as follows: maintenance of the fuel conversion policy, reinforcement of the regional stationary source emission standard, and enlargement of the stack TMS.

• Journal of Korean Society of Coastal and Ocean Engineers
• /
• v.20 no.4
• /
• pp.401-412
• /
• 2008

Simulations of three-dimensional numerical wave tank are performed to investigate wave force acting on a large cylindrical structure and consequent wave deformation, which are induced by bore after breaking waves. The numerical model is based on the three-dimensional Navier-Stokes equations with a finite-difference method combined with a volume of fluid(VOF) method, which is capable of tracking the complex free surface, including wave breaking. In order to promote wave breaking of the incident wave, the approach slope was built seaward of the structure with a constant slope and a large cylindrical structure was installed on a flat bed. The incident waves were broken on the approach slope or flat bed by its wave height. In the present study, all waves acting on the large cylindrical structure were limited to breaking bore after wave breaking. The effects of the position of the structure and the incident wave height on the wave force and wave transformations were mainly investigated with the concern of wave breaking. Further, the relations between the variation of wave energy by wave propagation after wave breaking and wave force acting on the structure were discussed to give the understanding of the full-linear wave-structure interactions in three-dimensional wave fields.

• Applied Microscopy
• /
• v.30 no.1
• /
• pp.73-80
• /
• 2000

Di-(2-ethylhexyl)phthalate (DEHP) has been known as one of endocrine disruptors. The present study was carried out to investigate the alterations of fine structure in rat seminal vesicle after oral intubation of DEHP in dosages of 1g/kg/day, 2g/kg/day or 3g/kg/day respectively in 0.5 ml of corn oil for If days. In rats treated with DEHP for 15 days, seminal vesicle exhibited extensive histological alterations compared to those observed in control groups. The size of the seminal vesicle and the mucosal folds decreased, but the lamina propria was considerably thickened. The ultrastructural changes of epithelial cells in seminal vesicle of rat treated with DEHP were characterized by the high nuclear/cytoplasmic ratio and the increased beterochromatin within irregular nuclear envelope. And also, the rough endoplasmic reticulum, Golgi complex and secretory vesicles were poorly developed. In conclusion, DEHP caused the ultrastructural and functional alterations of seminal vesicle in rats dose-dependently. It is suggested that these detrimental effects of DEHP on seminal vesicle are derived from the decrease level of testosterone.

• Journal of Applied Biological Chemistry
• /
• v.55 no.4
• /
• pp.227-234
• /
• 2012

We observed that oil began to accumulate at 25 seed days after flowering (DAF) and reached the maximum potential at 35 seed DAF of oilseed rape, and the greatest weight of 100 seeds was obtained at 35 seed DAF. To survey a broad analysis of gene expression in developing embryos of Brassica napus, the Bn 300k microarray have been constructed. The Bn 300k Microarrary was designed from 80,696 unigenes clustered from 543,448 ESTs and 780 cDNA at NCBI. These arrays have been hybridized in a series of experiments with probes derived from seeds and leaf of B. napus. Approximately 8.5% of the 7,000 genes were expressed as ratios 2-fold higher in seed (25 DAF) than leaves and 0.4% at ratios 10. Also we observed that storage and cell differentiation-related genes were highly expressed at 10 DAF, whereas energy-related genes including fatty acid metabolism were increased up depending on seed maturation using Microarray, which was confirmed by reverse transcriptase polymerase chain reaction. These results suggest that B. napus arrays provide a very useful data set of seed-specific expression that can be further analyzed by examination of the promoter regions of these genes and help our understanding of the complex regulatory network in developing seeds.