• Clean Technology
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• v.28 no.2
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• pp.163-173
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• 2022

Research and development of biofuels as one of the means to mitigate global warming and to avoid fossil fuel depletion has occurred for more than 30 years. However, there has only been limited distribution of a few first- and second-generation biofuels, and widespread supply and consumption of biofuels is still far from a reality. Although a relatively recently studied third-generation biofuel derived from seaweed biomass has been shown to have many advantages, it is yet to be deployed in commercial-scale seaweed biorefineries. This review paper examines the advantages and disadvantages of seaweed biorefineries for the entire value chain covering from seaweed and its cultivation to biofuel production based on an extensive literature search and the author's experience of conducting feasibility studies pertaining to seaweed biorefineries for over 10 years. For this purpose, the literature survey will cover the current status of seaweed production and its research and development worldwide, conversion technologies for biofuel production from seaweed based on bench-scale experiments, and large-scale techno-economic feasibility studies for seaweed conversion to biofuels and bioenergy. In addition, the main problems expected with the commercialization of seaweed-based biofuels will be identified. Finally, the current status of seaweed biorefinery technology and the author's views on its promising future will be summarized.

• Journal of Plant Biotechnology
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• v.37 no.3
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• pp.305-312
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• 2010

During a last decade, the introduced traits in commercialized GM crops have been diversified from a simple trait such as herbicide resistance gene or insectresistance gene which are related to the crop production into more complicated traits such as modification of fatty acid or essential amino acid composition, modified coloring pattern of flower. In addition, it was investigated that several other GM crops bearing more refined traits expected to lead next generation are also awaiting for risk assessment (RA) or under field test for the preparation of RA in the near future. These GM crops include abiotic stress resistance including drought or cold, increased biomass, production of bioethanol or diesel, production of pharmaceuticals or functional materials for industrial. In particular, in 2008 and 2009, it was reported that the highest number of GM crops for molecular farming are under developed in laboratory or green house level in all the world. Likewise, in Korea, 171 events from 49 plant species are under developed to introduce several important traits. At present, about 10 events are under field test to select elite lines for RA application. For the first time, herbicide resistance turfgrass developed by Korean research team has been submitted for RA and currently under requested for additional data. Moreover, GM rice resistant to leaf roll (folder) disease is expected as a next event to be submitted for RA application.

• Spatial Information Research
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• v.18 no.3
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• pp.23-32
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• 2010

LIDAR data are useful for forest applications such as bare-earth DEM generation for forest areas, and estimation of tree height and forest biomass. As a core preprocessing procedure for most forest applications, this study attempts to develop an efficient method to detect forest areas from LIDAR data. First, we suggest three perceptual cues based on multiple return characteristics, height deviation and spatial distribution, being expected as reliable perceptual cues for forest area detection from LIDAR data. We then classify the potential forest areas based on the individual cue and refine them with a bi-morphological process to eliminate falsely detected areas and smoothing the boundaries. The final refined forest areas have been compared with the reference data manually generated with an aerial image. All the methods based on three types of cues show the accuracy of more than 90%. Particularly, the method based on multiple returns is slightly better than other two cues in terms of the simplicity and accuracy. Also, it is shown that the combination of the individual results from each cue can enhance the classification accuracy.

• Journal of the Korean Electrochemical Society
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• v.21 no.4
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• pp.61-67
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• 2018

As emerging the new electric devices, the commercial lithium ion batteries have faced with various challenges. In this regard, many efforts to solve challenges have been tried. In order to solve the above problems in terms of development of a new secondary battery, we successfully demonstrated the two electrocatalysts, such as MCWB and PPY hydrogel, PPY hydrogel and MCWB showed typical H3-type BET isotherm, indicating that micro- and mesopores existed. Especially, in terms of voltage efficiency at the first cycle, PPY hydrogel was higher than that of MCWB, but lower than that of PtC. More interestingly, the PPY hygrogel based seawater battery exhibited charge-discharge reversibility during 20 cycles, and the voltage efficiencies ranged from 70.32 % to 77.35 % in cyclic performance test.

• Journal of the Korea Organic Resources Recycling Association
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• v.6 no.1
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• pp.31-42
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• 1998

A fundamental study on methane conversion for the collection organic wastes of agriculture, forestry and fishers was performed in a laboratory scale. As a result, selected Run B sample were obtained 18.41 C/N Ratio and 168.96 mg/L TCOD; Under the biochemical methane potential test, theoretical and actual methane generation was 313.6 mg/L VS added and 234.2 mg/L VS added, respectively; However, methane conversion from Run B were occurred 74% by anaerobic digestion. By the first order reaction kinetics, kinetic constant were $0.2476d^{-1}$ for Run B. Three steps fill-up filter reactor was evaluated methane content 16% up to promote than blank reactor; TCOD and SCOD have reduced 44.7% and 44.2%, respectively.

• Journal of Life Science
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• v.31 no.2
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• pp.183-191
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• 2021

Euglena gracilis is a microalga of great biotechnological interest that can create high levels of bioactive compounds, such as tocopherol, paramylon, and folic acid. The objective of this study was to investigate the biological activities of extracts from E. gracilis, especially those focused on immunological activity. E. gracilis biomass was extracted with hot water (HWE) and the remaining pellet was continuously extracted with methanol (HWME). First, we examined the effect of two extracts from E. gracilis on the production of nitric oxide (NO) and the expression of pro-inflammation cytokines, including IL-1β, IL-6, and TNF-α in murine macrophage RAW 264.7 cells. HWE treatment dose-dependently increased the production of IL-1β and TNF-α. On the other hand, treatment with HWME significantly decreased the generation of NO and pro-inflammatory cytokines (IL-6 and TNF-α) in lipopolysaccharide (LPS)-stimulated macrophage cells. In addition, other biological activities of the extracts were further analyzed: α-glucosidase inhibition, protein tyrosine phosphatase (PTP1B) inhibition, tyrosinase inhibition, xanthine oxidase (XO) inhibition, and angiotensin-converting enzyme (ACE) inhibition. Analysis of these biological activities showed that HWE has more inhibitory effects than HWME against α-glucosidase, tyrosinase, and XO agents. However, the inhibition of PTP1B and ACE with HWME were higher than with HWE. Taken together, the results suggested that E. gracilis possesses various biological activities―especially immunological capabilities―through regulation of cytokine production. Therefore, E. gracilis extract may be potentially useful for food material with immune-regulating effects.