• Journal of Korean Society of Forest Science
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• v.106 no.1
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• pp.54-62
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• 2017

This study was carried to develop the chip-harvester and to analysis the operation productivity and cost for effective collection and forwarding of forest biomass. Main target specification of chip-harvester is speed of 8km/h, maximum climbing capacity of $30^{\circ}$ and maximum load capability of 2000 kg. Body structure is articulate type to reduce turning radius. Driving equipment is six-wheel drive, and a rear wheel is tandem bogie type to increase grip force. As a result of the driving test about developed chip-harvester, driving speed was 6.9 km/hr and 8.1 km/hr in ${\pm}10%$ slope with loaded and 7.3 km/hr and 7.9 km/hr in ${\pm}10%$ slope without load. As a result of the operation productivity and cost, operation productivity of grinding and forwarding was approximately $10m^3$ per day, and operation cost was 393,126 won per day.

• Proceedings of the Korea Society of Environmental Biology Conference
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• 2003.11a
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• pp.92-97
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• 2003

Community structure of macrobenthos was studied on Angol clam farming ground of Chinhae Bay in the southern coast of Korea. Macrobenthos samples were collected monthly using a quadrate at each station from March 1998. Macrobenthos samples were seived by 1.0mm mesh seive. Mean grain size was 0.267 mm. A total of 111 macrobenthos species were sampled with a mean density of 1,651ind/m$^2$and biomass of 1466.7wwt.g/m$^2$. Annelida was density-dominant faunal group with a mean density of 818ind/m$^2$, comprising of 49.6% of the total density of the macrobenthos. It was followed by Mollusca with 660ind/m$^2$(40.0%). Mollusca was biomass-dominant faunal group. Major dominant species in the number of individual were Ruditapes philippinarum (375ind/m$^2$), Batillaria cumingi (208ind/m$^2$), Cirrformia tentaculata (167ind/m$^2$), Ceratonereis erithraeensis (151ind/m$^2$), Capitella capitata (111ind/m$^2$) and Sigambra tentaculata (91ind/m$^2$). Major dominant species in the biomass were Ruditapes philippinarum (1156.6wwt.g/m$^2$), Batillaria cumingi (111.0wwt.g/m$^2$) and Cyclina sinenis (106.2wwt.g/m$^2$). The species diversity was increased gradually during the study period. Increasing of species diversity was due to not only increasing of number of species but also decreasing of dominance of some polycheates. Contents of silt-clay was increased gradually in the intertidal zone.

• Journal of Korean Society on Water Environment
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• v.36 no.6
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• pp.581-591
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• 2020

In this study, two types of reactors were operated to examine the properties of methanol uptake under the high-rate denitrification process. In a sequencing batch reactor, the denitrifying activity was enriched up to 0.80 g-N/g-VSS-day for 72 days. Then, the enriched denitrifying sludge was transferred to a completely stirred tank reactor (CSTR). At the final phase on Day 46-50, the nitrogen removal efficiency was around 100% and the total nitrogen removal rate reached 0.097±0.003 kg-N/㎥-day. During the continuous process, the sludge settling index (SVI30) was stabilized as 118.3 mL/g with the biomass concentration of 1,607 mg/L. The continuous denitrifying process was accelerated by using a sequencing batch reactor (SBR) with a total nitrogen removal rate of 0.403±0.029 kg-N/㎥-day with a high biomass concentration of 8,433 mg-VSS/L. Because the reactor was open to ambient air with the dissolved oxygen range of 0.2-0.5 mg-O2/L, an increased organic carbon requirement of 5.58±0.70 COD/NO3--N was shown for the SBR in comparison to the value of 4.13±0.94 for the test of the same biomass in a completely anaerobic batch reactor. The molecular analysis based on the 16S rRNA gene showed that Methyloversatilis discipulorum and Hyphomicrobium zavarzinii were the responsible denitrifiers with the sole organic carbon source of methanol.

• Carbon letters
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• v.11 no.3
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• pp.224-234
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• 2010

Four activated carbons were produced by two-stage process as followings; semi-carbonization of indigenous biomass waste, i.e. cotton stalks, followed by chemical activation with KOH under various activation temperatures and chemical ratios of KOH to semi-carbonized cotton stalks (CCS). The surface area, total pore volume and average pore diameter were evaluated by $N_2$-adsorption at 77 K. The surface morphology and oxygen functional groups were determined by SEM and FTIR, respectively. Batch equilibrium and kinetic studies were carried out by using a basic dye, methylene blue as a probe molecule to evaluate the adsorption capacity and mechanism over the produced carbons. The obtained activated carbon (CCS-1K800) exhibited highly microporous structure with high surface area of 950 $m^2/g$, total pore volume of 0.423 $cm^3/g$ and average pore diameter of 17.8 ${\AA}$. The isotherm data fitted well to the Langmuir isotherm with monolayer adsorption capacity of 222 mg/g for CCS-1K800. The kinetic data obtained at different concentrations were analyzed using a pseudo-first-order, pseudo-second-order and intraparticle diffusion equations. The pseudo-second-order model fitted better for kinetic removal of MB dye. The results indicate that such laboratory carbons could be employed as low cost alternative to commercial carbons in wastewater treatment.

• Asian-Australasian Journal of Animal Sciences
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• v.14 no.6
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• pp.862-879
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• 2001

The walls of all higher plants are organized as a cellulosic, fibrillar phase embedded in a matrix phase composed of non-cellulosic polysaccharides, some proteins and, in most secondary walls, lignin. At the effective utilization of plant biomass, qualitative and quantitative analyses of plant cell walls are essential. Structural features of individual components are being clarified using newly developed equipments and techniques. However, "empirical" procedures to elucidate plant cell walls, which are not due to scientific definition of components, are still applied in some fields. These procedures may give misunderstanding for the effective utilization of plant biomass. In addition, interesting the investigation of wall organization is moving towards not only qualitatively characterisation, but also quantitation of the associations between wall components. These involve polysaccharide-polysaccharide and polysaccharide-lignin cross-links. Investigation of the associations is being done in order to understand the chemical structure, organization and biosynthesis of the cell wall and physiology of the plants. Procedures for qualitative and quantitative analyses based on the definition of cell wall components are reviewed focussing in nutritional elucidation of forage grasses by ruminant microorganisms.

• Ocean and Polar Research
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• v.22 no.1
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• pp.25-36
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• 2000

The polychaeta fauna of the benthos and fouling of the northwestern part of the East Sea was studied during the period of 1971-1998. Three introduced species of polychaetes: Hydorides elegans (Haswell), Polydora limicola Annenkova, and Pseudopotamilla occelata Moore were found. H. elegans was discovered only on the artificial surfaces in Golden Horn Inlet (port Vladivostok), where this species may occur because of hermal pollution due to the discharge of warm waters of the water cooling system of Thermal-Electric Power Station-2 (TEPS-2) in Vladivostok which has been in function since 1971. The abundant population of H. elegans exists in the bay throughout the year and is capable of reproduction. The biomass of H. elegans may reach several $kg/m^2$ in August-September. P. limicola was found at the same time in the fouling of hydrotechnical structures of Vladivostok, Nakhodka, Holmsk and Uglegorsk ports with a biomass of $1-3kg/m^2$. Slow introduction of P. limicola occurs by coastal sail ships at present. The invasion of P. occelata into Peter the Great Bay may be an example of introduction and subsequent naturalization, which produced considerable changes in the structure of benthic communities. The three species of polychaetous sessile organisms and their invasion occurred by ocean and coasters sea-going ships (unintentional transport vectors). H. elegans and P. occelata were most probably transported to the northwestern part of the East Sea from Japan, and P.

• Journal of Fisheries and Marine Sciences Education
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• v.28 no.1
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• pp.83-90
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• 2016

A subtidal marine benthic algal vegetation at Ulleungdo Island, the eastern coast of Korea was investigated to clarify the community structure and vertical distribution by quadrat method at seven stations in May and August 2014. The total number of marine algal species was 148 species composed of the green algae of 12 species, the brown algae of 40 species and the red algae of 96 species. Mean biomass in dry weight was $94.8g\;dry\;weight\;m^{-2}$ in study sites, $98.1g\;dry\;weight\;m^{-2}$ in upper tidal level, and $86.6g\;dry\;weight\;m^{-2}$ in middle level. The R/P and (R+C)/P value reflecting flora characteristic were 1.9 and 2.3, respectively. Three groups produced by cluster analysis, one including sites Neunggeol, Daepung, Jukdo, second including sites Gongam, Ssangjeongcho and the other including sites Gwaneum, Hangnam, showed meaningful difference in similarity (about 40%), each other. The number of marine algal species and biomass in Ulleungdo Island area were markedly reduced comparing that in the previous studies. This result may suggest probably change of algal vegetation in future, considering the physical and chemical pollutions loaded in the coastal marine environment of this area.

• Plant Journal
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• v.7 no.3
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• pp.42-47
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• 2011

One of domestic power generation companies, Korea East-West Power Corporation(EWP) had no performance in overseas business just two short years ago. However, EWP has accomplished breakthrough results with the profit of KRW 17.8 billion in 2010, only overseas business part. With overseas power plant growing fast, there is a possibility that EWP may face the limitation of sustainable growth with the current low income structure, which is mainly focused on commissioning and power plant management. Accordingly, this study was made on overseas biomass plant business participation plan through the establishment of joint venture. The characteristics of a joint venture establishment was searched, choosing business partner; the ideas of how to organize a joint venture was drawn, what the role of each partner in joint venture is, and what proper capital share is; and chose business field, considering changing global energy mix, renewable energy market scale, and growth prospects. Considering government policy for renewable energy vitalization and renewable energy market share, We chose the European union as a market to which our business entered.

• Journal of the Korean Wood Science and Technology
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• v.42 no.2
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• pp.172-182
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• 2014

Extraction is a necessary element in the bioconversion of lignocellulosics to fuels and chemicals. Although various forms of chemical pretreatment of cellulosic materials have been proposed, their effectiveness varies depending on the treatment conditions and substrate. In this study, mixed hardwood (MH) and loblolly pine (LP) were pretreated with dilute acid in a 100 mL accelerated solvent extraction (ASE) at the predetermined optimal conditions: temperature: $170^{\circ}C$, acid concentration: 0.5% (w/v), and reaction time: 2~64 min. This method was highly effective for extracting the hemicellulose fraction. Total xmg (defined as the sum of xylose, mannose, and galactose) can be extracted from milled MH and LP through pressurized dilute acid treatment in maximum yields of 12.6 g/L and 15.3 g/L, respectively, representing 60.5% and 70.4% of the maximum possible yields, respectively. The crystallinity index increased upon pretreatment, reflecting the removal of the amorphous portion of biomass. The crystalline structure of the cellulose in the biomass, however, was not changed by the ASE extraction process.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.47 no.6
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• pp.960-972
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• 2014

Marine algal flora and community structure were seasonally investigated at Oryukdo, on the southeast coast of Korea, from March 2011 to February 2014. A Total of 66 seaweed species including 6 green, 7 brown and 53 red algae were identified and 23 species were found throughout the survey period. Seaweed biomass was maximal during summer in 2012 (2276.2 g wet weight $m^{-2}$) and minimal in winter in 2012 (9.1 g wet weight $m^{-2}$). The dominant species in term of biomass were Undaria pinnatifida, Dictyopteris prolifera, Dictyota dichotoma, Sargassum horneri, Rhodymenia intricata, Acrosorium polyneurum, and Polyneura japonica during the suvery period. The flora could be classified into six functional groups: coarsely branched form (30.3%), filamentous form (24.2%), thick leather form (19.7%), sheet form (15.2%), jointed calcareous form (7.6%), and crustose form (3.0%). The numbers of marine algal species in the Oryukdo area were markedly reduced when compared with previous studies at Dongbaekseom in 1971. These results suggest possible future changes in the algal vegetation, considering the physical and chemical pollution loadings in the coastal marine environment of this area.