• Korean Chemical Engineering Research
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• v.60 no.1
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• pp.116-124
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• 2022

In this study, waste air containing ethanol and hydrogen sulfide, was treated by an integrated hybrid system composed of two alternatively-operating UV/photocatalytic reactor-process and biofilter processes of a biofilter system having two units with an improved design (R reactor) and a conventional biofilter (L reactor). Both a pressure drop (△p) per unit process of the integrated hybrid system and a microbe-population-distribution of each biofilter process were observed. The △p of the UV/photocatalytic reactor process turned out very negligible. The △p of the L reactor was observed to increase continuously to 4.0~5.0 mmH₂O (i.e., 5.0~6.25 mmH₂O/m). In case of R reactor, its △p showed the one below ca. 16~20% of the △p of the L reactor. Adopting such microbes-carrying biofilter media with high porosity as waste-tire crumb media, and the improved biofilter design, contributed to △p of this study, reduced by ca. 37~50% and 40~53%, respectively, from the reported △p of conventional biofilter packed with biofilter media of the mixture (50:50) of wood chip and wood bark. In addition, the △p of R reactor in this study, reduced by ca. 80% from the reported △p of conventional biofilter packed with biofilter media of the mixture (75:25) of scoria with high porosity and compost, was mainly attributed to adopting the improved biofilter design. On the other hand, in case of L reactor, the CFU counts in its lowest column was analyzed double as much as those in any other columns. However, in case of R reactor, its CFU counts were bigger by 50% than the one of L reactor and its microbes were evenly distributed at its higher and lower columns of R_dn reactor and R_up reactor. This phenomena was attributed to an even moisture distribution of 50~55% of R reactor at its higher and lower columns. Therefore, R reactor showed superb characteristics in terms of both △p and microbe-population-distribution, compared to L reactor.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.32 no.1
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• pp.93-106
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• 2014

In this study, Analyze environment of location, investigation into vegetation resources, survey management status and establish to classify the management area for Natural monument No.374 Pyengdae-ri Torreya nucifera forest. The results were as follows: First, Torreya nucifera forest is concerned about influence of development caused by utilization of land changes to agricultural region. Thus, establish to preservation management plan for preservation of prototypical and should be excluded development activity to cause the change of terrain that Gotjawal in the Torreya nucifera forest is factor of base for generating species diversity. Secondly, Torreya nucifera forest summarized as 402 taxa composed 91 familly 263 genus, 353 species, 41 varieties and 8 forms. The distribution of plants for the first grade & second grade appear of endangered plant to Ministry of Environment specify. But, critically endangered in forest by changes in habitat, diseases and illegal overcatching. Therefore, when establishing forest management plan should be considered for put priority on protection. Thirdly, Torreya nucifera representing the upper layer of the vegetation structure. But, old tree oriented management and conservation strategy result in poor age structure. Furthermore, desiccation of forest on artificial management and decline in Torreya nucifera habitat on ecological succession can indicate a problem in forest. Therefore, establish plan such as regulation of population density and sapling tree proliferation for sustainable characteristics of the Torreya nucifera forest. Fourth, Appear to damaged of trails caused by use. Especially, Scoria way occurs a lot of damaged and higher than the share ratio of each section. Therefore, share ratio reduction Plan should be considered through the additional development of tourism routes rather than the replacement of Scoria. Fifth, Representing high preference of the Torreya nucifera forest tourist factor confirmed the plant elements. It is sensitive to usage pressure. And requires continuous monitoring by characteristic of Non-permanent. In addition, need an additional plan such as additional development of tourism elements and active utilizing an element of high preference. Sixth, Strength of protected should be differently accordance with importance. First grade area have to maintenance of plant population and natural habitats. Set the direction of the management. Second grade areas focus on annual regeneration of the forest. Third grade area should be utilized demonstration forest or set to the area for proliferate sapling. Fourth grade areas require the introduced of partial rest system that disturbance are often found in proper vegetation. Fifth grade area appropriate to the service area for promoting tourism by utilizing natural resources in Torreya nucifera forest. Furthermore, installation of a buffer zone in relatively low ratings area and periodic monitoring to the improvement of edge effect that adjacent areas of different class.

• Geophysics and Geophysical Exploration
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• v.11 no.4
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• pp.335-342
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• 2008

Electrical resistivity and seismic refraction surveys were conducted to investigate geologic structures and geotechnical characteristics of the subsurface, along with rock physical property measurements in Dokdo island. The survey results in Seodo island show that the fault adjacent to the fisherman's shelter is a normal fault and extended towards the NW direction, and that Bedded Lapilli Tuff in the downstream was more severely influenced by weathering and erosion than Trachy Andesite II in the upstream of the survey area. In Dongdo island, Trachy Andesite III and Scoria Bedded Lapilli Tuff were severely weathered and eroded, considered as weathered to soft rock formations, and their weathered zone becomes thicker towards the antiaircraft facility in the NE direction of the survey area. The study results also illustrate that Trachyte and Trachy Andesite are hardest, Massive Tuff Breccia is next, and Stratified Ash Tuff is the most soft rock in Dokdo island.

• Journal of the Korean association of regional geographers
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• v.14 no.3
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• pp.212-223
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• 2008

The rainfall partitioning in a monogenetic volcano has been analysed using the hydrological data of a small catchment on Eoseungsaeng-oreum of Mount Halla and the meterological data of Eorimok Automated Weather System. The experimental catchment extends from 965 m to 1,169 m in altitude, and has an catchment area of $51,000\;m^2$ Eoseungsaeng-oreum is the scoria cone predominantly covered with Carpinus laxiflora and Quercus serrata. The analyzed periods are April 30 to September 12 and October 7 to November 19, 2007. The experimental catchment exhibits the total precipitation of 2,296.5 mm. Surface runoff amounts to 465 mm that is equivalent to 20.2% of the precipitation. By contrast, evapotranspiration accounts for 25.9% of the precipitation, and the remnant of 1,236.5 mm deep1y percolates underground through a basement. The rainy summer season, in particular, shows the highest deep percolation ratio of 62.2%. The deep percolation ratio of the experimental catchment is at 1east more two times than the ratio of a gneiss basin in Korea Peninsular. It has suggested that the experimental catchment is characterized by the higher portion of deep percolation in rainfall partitioning which reflects the highly permeable lithology in Jeju Island.

• The Journal of the Petrological Society of Korea
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• v.26 no.3
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• pp.221-234
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• 2017

The Baengnokdam, the summit crater of Mt. Halla, is one of the representative geosites of World Natural Heritage and Global Geopark in Jeju Island. The crater is marked by two distinctive volcanic lithofacies that comprise: 1) a trachytic lava dome to the west of the crater and 2) trachybasaltic lava flow units covering the gentle eastern slope of the mountain. This study focuses on understanding the formative process of this peculiar volcanic lithofacies association at the summit of Mt. Halla through field observation and optically stimulated luminescence (OSL) dating of the sediments underlying the craterforming volcanics. The trachyte dome to the west of the crater is subdivided into 3 facies units that include: 1) the trachyte breccias originating from initial dome collapse, 2) the trachyte lava-flow unit and 3) the domal main body. On the other side, the trachybasalt is subdivided into 2 facies units that include: 1) the spatter and scoria deposit from the early explosive eruption and 2) lava-flow unit from the later effusion eruption. Quartz OSL dating on the sediments underlying the trachyte breccias and the trachybasaltic lava-flow unit reveals ages of ca. 37 ka and ca. 21 ka, respectively. The results point toward that the Baengnokdam summit crater was formed by eruption of trachybasaltic magma at about 19~21 ka after the trachyte dome formed later than 37 ka.

• Journal of Bio-Environment Control
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• v.20 no.4
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• pp.346-351
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• 2011

This research was done to identify the mass propagation method in winter daphne (Daphne odora Thunb) using its softwood cuttings and to investigate its plant characters established at different light and soil conditions as an indoor plant. Cuttings from winter daphne were taken and grown in different treatment consisted of rooting media (perlite, vermiculite, perlite + vermiculite (1 : 1) and commercial horticulture media soil), indole butyric acid (IBA) hormone concentrations (0, 100, 500, 1000 ppm and Rootone) and date of cutting. Transplants were grown at different light intensities (100, 1000, 2500 lux and control) and growing media. Results showed that cuttings grown in perlite + vermiculite (1 : 1) gave higher percentage (100%) rooting. Cuttings treated with Rootone and IBA 100 ppm showed good rooting growth and cutting taken in June, 25 gave the highest rooting (96.7%). The best plant growth obtained at 1000 lux (56~60 ${\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$) followed by 2500 lux (125~130 ${\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$) and scoria mixed with commercial horticulture media soil showed better growth of transplants.

• Korean Journal of Medicinal Crop Science
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• v.11 no.1
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• pp.46-52
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• 2003

This experiment was conducted to investigate the propagation for mass production of Acanthopanax koreanum NAKAI utilized for health food and medicine material. Germination rate of A. koreanum seeds were 64% when seeds were stored at 15 for 60 days and then were treated with 50 ppm of kinetin and dormancy were broken at 5 for 60 days. Rooting rates of green-wood cuttings treated with IBA 100 ppm, NAA 50 ppm, and IAA 100 ppm were 61.7, 56.7, and 60.0%, respectively. Rooting rates of greenwood cuttings treated with Rooton in scoria + horticulture media and volcanic ash were 76.7 and 66.7%, respectively. Survival rate of seedlings planted on Aug. 10 was highest (96%) under 75% shading net while shoot growth was best under 55% shading net. Survival rate of seedlings planted on May 2 was highest (91%) 55% shading net, and shoot growth was also best 55% under shading net.

• Journal of the Korean Geographical Society
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• v.41 no.4 s.115
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• pp.391-403
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• 2006

The Hanon volcano located in the southern pan of Cheju Island, Korea has a wetland in its crater being used as a farmland. Previous researchers presumed this wetland was a maar lake in the past. Based on the seismic refraction method, the wetland sediment layer was estimated between 5 to 14 m deep, which is mostly in accordance with previous researches. However, this shows only the depths at some sites, not representing the whole spatial distribution. This study is an attempt to reconstruct the volcanic lake in Hanon crater by applying the spatial statistical techniques based on the depth information from the seismic survey and known data. The procedure of reconstruction is as follows: First, the depth information from the seismic survey and known data were collected and it was interpolated by IDW and Ordinary Kriging method. Next, with the interpolation map and the present DEM the paleo DEM was constructed. Finally, using the paleo lake level on core data, the boundary of volcanic lake was extracted from the paleo DEM. The reconstructed lake resembles a half-moon in the north of the central scoria cone. It is estimated that the lake was 5 m deep on average and 13 m deep at the deepest point. Although there are slight differences according to the interpolation techniques, it is calculated that the area of the lake was between 184,000 and $190000m^2,$ and its volume approximately $869,760m^3$. Because of the continuous deposition processes after the crater formation, the reconstructed volcanic lake would not indicate an actual lake at a specific time. Nevertheless, it offers a significant clue regarding the inner morphology and evolution of the crater.

• Economic and Environmental Geology
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• v.54 no.2
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• pp.187-197
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• 2021

The Hyeongjeseom (Islet) is an erosional remnant of volcano which is located about 2 km northeast of sea shore of the Songaksan tuff ring, and is composed of volcaniclastic deposit, agglomerate and scoria deposit, ponded lava, aa lava flows, reworked deposit and beach deposit in ascending order from the base. The volcano is formed by volcaniclastic deposits and lava flows that recorded a transition from initial phreatomagmatic to magmatic explosions followed by lava effusion. It is interpreted that the outcropped volcaniclastic deposit may be a remaining portion of outer ring of a tuff cone. A bomb and a ponded lava yield geochemically basaltic trachyandesite compositions (SiO2 51.3 wt%, Na2O+K2O 6.0 wt%) and belong to olivine basalt with scarce (<5 %) phenocrysts of olivine, petrographically. By incremental heating Ar-Ar dating method, the plateau age of lava flow in the Heongjesom is 9.2±3.6(2σ) ka, implying that the volcanism of Heongjeseom may have occurred earlier than the Songaksan tuff ring which erupted ca. 3.7 ka. It still remains a task to find a volcano which matches with a historical record of volcanic activity that occurred a thousand years ago.

• The Journal of the Petrological Society of Korea
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• v.19 no.2
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• pp.141-156
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• 2010

Dokdo Island, Korea, is located in the East Sea belonging to back arc basin. In this study we examined petrology and geochemistry of massive tuffaceous breccia (MTB) from Dongdo (Eastern islet) and Seodo(Western islet), the two largest islands of Dokdo. Field studies and chemical analysis distinguish the MTB in Dongdo and Seodo. The Dongdo MTB (DMTB) is exposed up to 50 m on the ocean cliff and it has dominant basalt and trachybasalt with moderate amount of trachyte and scoria. On the other hand, Seodo MTB (SMTB), which is preserved between trachyte dike and trachyandesite, is composed of roughly equal amounts of basalt, trachybasalt and trachyte. The location of the islets were related to the source vent having in contact with underlying trachyte lava and differential pyroclastic deposits made them different characteristics. According to trace element analysis of trachytic volcanic clasts, the Ba concentration ranges from 66 to 103 ppm and Sr varies from 44 to 56 ppm in DMTB. However, Br and Sr in SMTB correspondingly showed relatively wide ranges: Br 785-1259 ppm and Sr 466-1230 ppm. These differential trends between DMTB and SMTB, along with the difference in P and Ti, indicate that the crystallization of alkali feldspar, feldspathoid, biotite, apatite and titanium took place differently. Nevertheless, DMTB and SMTB are similar in REE patterns and they are correspondingly characterized by high LREE, low HREE and similar $(La/Yb)_N$ values with 23.9-40.2 in DMTB and 27.4-32.9 in SMTB. These patterns suggest that Dongdo and Seodo might be originated from coeval magma suites. Dokdo island shows high concentrations of Ba, K and Rb. These signatures mark a result attributed to the mantle upwelling because the magma derived from the asthenosphere was metasomatized with subduction-related fluids.