• Journal of Appropriate Technology
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• v.5 no.2
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• pp.91-96
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• 2019

Microalgae do not require much land and make a higher efficient oil production. However, it costs still much higher than other biodiesel resources, such as crops. Sugars charge 80% of culture media when microalgae are massively cultured in the fermenter. This study aims to develop a cost-efficient process for sugar production from Chinese cabbage byproducts. Pre-treatment with 0.25% H₂SO₄ was most effective when chopped cabbage was incubated 50℃/130 rpm for 24 hours. To hydrolyze cabbage cellulose, we used cellulases secreted from Trichoderma. harzianum. T. harzianum was cultured at 28℃/pH 7/130 rpm for five days. Optimal enzymatic activity of cellulase was obtained by incubating at 0.24 FPU/ml/45℃/pH 5/130 rpm for three days. In comparison to other agricultural waste, such as rice straw, green tea leaves, and palm residue, Chinese cabbage produced the highest sugar yield. We found the optimal conditions to produce sugar from Chinese cabbage byproducts as a carbon source to culture biodiesel-producing microalgae. The efficient process developed in this study helps microalgae as a sustainable alternative energy source by cost-down.

• Korea Trade Review
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• v.43 no.3
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• pp.125-145
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• 2018

The Baltic Shipping Exchange is reporting the Baltic Dry Index (BDI) which represents the average charter rate for bulk carriers transporting major cargoes such as iron ore, coal, grain, and so on. And the current BDI index is reflected in the proportion of capesize 40%, panamax 30% and spramax 30%. Like mentioned above, the capesize plays a major role among the various sizes of bulk carriers and this study is to analyze the influence of the factors influencing on charter rate of capesize carriers which transport iron ore and coal as the major cargoes. For this purpose, this study verified causality between variables using Vector Error Correction Model (VECM) and tried to derive a long-run equilibrium model between the dependent variable and independent variables. Regression analysis showed that every six independent variable has a significant effect on the capesize charter rate, even at the 1% level of significance. Charter rate decreases by 0.08% when capesize total fleet increases by 1%, charter rate increases by 0.04% when bunker oil price increases by 1%, and charter rate decreases by 0.01% when Yen/Dollar rate increases by 1%. And charter rate increases by 0.02% when global GDP increases by one unit (1%). In addition, the increase in cargo volume of iron ore and coal which are major transportation items of capesize carriers has also been shown to increase charter rates. Charter rate increases by 0.11% in case of 1% increase in iron ore cargo volume, and 0.09% in case of 1% increase in coal cargo volume. Although there have been some studies to analyze the influence of factors affecting the charterage of bulk carriers in the past, there have been few studies on the analysis of specific size vessels. At present moment when ship size is getting bigger, this study carried out research on capesize vessels, which are biggest among bulk carriers, and whose utilization is continuously increasing. This study is also expected to contribute to the establishment of trade policies for specific cargoes such as iron ore and coal.

• Journal of the Korean Institute of Gas
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• v.27 no.2
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• pp.39-48
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• 2023

This study presents the experimental results to measure the adsorption amount of methane gas by coal according to the conditions of a coalbed methane (CBM) reservoir. Adsorbed gas to coal seam particles was measured under reservoir conditions (normal pressure ~ 1,200 psi pressure range, temperature range15 ~ 45℃) using coal samples obtained from random mines in Kalimantan Island, North Indonesia. The obtained amount of absolute adsorbed gas was applied to triangular with linear interpolation to calculate the maximum amount of adsorbed gas according to temperature and pressure change, at which no experiment was performed. As a result, it was revealed that the amount of adsorbed gas to coal particles increased as the pressure increased and temperature decreased, but the increase of the amount of adsorbed gas decreased at more than an appropriate depth(1,000 ft). In the cleat permeability and cleat porosity for each depth of the coal bed considering the effective stress, the cleat permeability was 28.86 ~ 46.81 md, and the cleat porosity was 0.83 ~ 0.98%. This means that the gas productivity varies significantly with the depth because the reduction of the permeability according to the depth in the coal seam is significant. Therefore, a coalbed depth should be considered essential when designing the spacing of production wells in a coalbed methane reservoir in further study.

• Journal of Korean Medicine for Obesity Research
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• v.23 no.1
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• pp.1-9
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• 2023

Objectives: Noni fruit juice (NFJ) is liquor extracted from Morinda citrifolia (noni) fruit and has been used as an herbal remedy in many countries. However, the NFJ's anti-adipogenic and anti-inflammatory effects on adipocytes are poorly understood. The purpose of this study was to explore the commercially standardized NFJ effects on lipid accumulation throughout 3T3-L1 preadipocytes differentiation and interleukin-1β (IL-1β)-mediated inducible nitric oxide synthase (iNOS) expression in 3T3-L1 preadipocytes. Methods: Cellular lipid accumulation and triglyceride (TG) content in differentiating 3T3-L1 preadipocytes were assessed subsequently via the Oil Red O staining and AdipoRed assay. MTS assay was used to examine NFJ cytotoxicity in (differentiating) 3T3-L1 preadipocytes. Immunoblotting and reverse transcriptase polymerase chain reaction analysis were used to measure the expression levels of target protein and mRNA in (differentiating) 3T3-L1 preadipocytes, respectively. Results: NFJ treatment at 150 μL/mL led to a substantial reduction of fat accumulation and TG content during 3T3-L1 adipogenesis with no discernable impact on the cell viability. Of note, while NFJ treatment (150 μL/mL) largely inhibited the CCAAT/enhancer-binding protein-α (C/EBP-α) and peroxisome proliferator-activated receptor-β (PPAR-β) protein expressions, it did not influence PPAR-γ in differentiating 3T3-L1 preadipocytes. Of interest, treatment with IL-1β at 20 ng/mL for 4 hours elicited in firm induction of iNOS mRNA expression in 3T3-L1 preadipocytes. However, NFJ treatment at 100 or 200 μL/mL greatly attenuated the IL-1β-induced iNOS mRNA expression in 3T3-L1 preadipocytes. Conclusions: NFJ has anti-adipogenic and anti-inflammatory effects on (differentiating) 3T3-L1 preadipocytes which are in part intervened via control of the expression of C/EBP-α, PPAR-β, and iNOS.

• Science of Emotion and Sensibility
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• v.26 no.1
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• pp.79-86
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• 2023

This study aims to create a highly conductive E-textile made by recycling PET with a Dip-coating process. PET fiber with hydrophobic properties is characterized by the difficulty in imparting great conductivity when both Virgin and Recycled are made of electronic fibers through a Dip-coating process. To advance the effectiveness of the Dip-coating process, a sample made of recycled PET was surface modified for 50 w 5 minutes and 10 minutes employing a Covance-2mprfq model from FEMTO SCIENCE. After that, the sample was immersed in an SWCNT dispersion (.1 wt%, Carbon Co., Ltd.) for 5 minutes, and then dip coating was conducted to allow the solution to permeate well into the sample through a padder (DAELIM lab). After the procedure was completed, the resistance measurement was measured with a multimeter at both ends and then accurately remeasured with a wider electrode. As a result of this contemplation, it was affirmed that great conductivity might be given through an impregnation process through the plasma surface modification. When the surface modification was performed for 10 minutes, the resistance was reduced by up to 2.880 times. Dependent on the results of this research, E-fibers employed in the smart wearable sector can also be made of recycled materials, improving smart wearable products that can save oil resources and reduce carbon emissions.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.29 no.1D
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• pp.17-23
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• 2009

Due to the rapid increase of vehicles on the street, Korean society is facing worsening traffic congestions and air pollutions. Also, the oil price pickup has led to increasing need for the use of public transportation. In particular, transfering among public transportation may be a main factor for riders who are commuting for a long distance journey. In order to ensure such connectivity, transfer stations have been actively built in Korea. However, it would be necessary to shift those vehicles, from cars to public transportations by enhancing the users' satisfaction with public transportation through strategies for minimizing the users' waiting cost by building an efficient connective system between transportation modes as well as the preparation of aforementioned transfer stations. Therefore, this study aimed to develop an algorithm for minimizing transferring passengers' waiting costs based on service intervals of linked buses within the transfer facilities. In order to adjust the service interval, we calculated the total costs, involving the wait cost of transfer passengers and bus operation costs, and produced an allocation interval, that would minimize the costs. We selected a KTX departing from Seoul station, and a No. 6014 bus route in Gwangmyeong city where it starts from the Gwangmyeong station in order to for verifying the model. Then, the transfer passengers' total waitting cost was reduced equivalent to the maximum of 212 minutes, and it revealed that the model performed very effectively.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.30 no.1B
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• pp.101-105
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• 2010

Sunflower (Sunking4505) and Rape (Sunmang) are oil-seeds containing high oleic acid, and these are used for the production materials of bio-diesel and applying for phytoremediation. The effect of cadmium on germination rate and the growth of the plants is evaluated. Object seeds were placed in Cd (0, 1.5, 4, 12, 30, 60, 100, 150, 300, 500 mg/L) solutions for seven days, and germination rate, root length, shoot length, seedling length, and dry weight were observed. $IC_{50}$, seedling vigor index, and tolerance indices were computed, and data were statistically analyzed by Analysis of Variance (ANOVA). Germination rate as well as root, shoot, and seedling length decreased as the cadmium concentration increased except dry weight. The $IC_{50}$ of sunflower and rape are 112 and 10 mg-Cd/L, respectively. Only one of the sunflower seeds is germinated at 500 mg-Cd/L whereas rape seeds are not germinated more than 150 mg-Cd/L solution. Root has higher cadmium sensitivity than shoot, and sunflower has higher germination rate, growth, and seedling vigor index than rape. In case of tolerance indices, sunflower has lower value than rape at relatively low concentration, but has higher value at high concentration.

• Industry Promotion Research
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• v.8 no.1
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• pp.1-10
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• 2023

In this study, a formula (EJ-F101) was prepared to develop a raw material for acne-prone skin improvement using wheat germ extract, and a clinical trial cream was prepared and clinical trials were conducted. As a result of the analysis, when comparing before and after using the product, both the test group and the control group showed significant improvement effects in terms of open comedones, occluded comedones, papules, sebum and oil content in the facial region at 4 weeks after product use, compared to the control group in the test group which showed a more significant improvement effect. As a result of the survey on the efficacy of the product, most items showed higher positive answers in the test product compared to the control product four weeks after the use of the product, and about 43-81% of the study subjects answered positively in the test product, except for the "open surface" item. In addition, for all items related to the usability of the product, about 14-86% of the test group and 38-90% of the control group answered positively at the time point 4 weeks after using the product. As a result of skin safety evaluation, no adverse skin reactions were observed in all subjects of this study. Based on the above results, it is considered that the cream using wheat germ extract is suitable for use on acne-prone skin(non comedogenicity).

• Analytical Science and Technology
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• v.22 no.6
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• pp.471-479
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• 2009

This study was performed to improve the analytical methods and re-establish the regulatory standard of PCBs-containing solid wastes for sufficient management in which has been concerned internationally. To do this, the sampling, pre-treatment and quantification methods which were used in USA and Japan were discussed. It was thought properly that new standard of PCBs-containing solid wastes was established through correlation with PCBs concentration of transformer oil. The surface wipe sampling was selected in the nonporous materials and cutting sampling in the porous materials. In the absence of transformer oils, electrical equipment is PCB-contaminated if it has PCBs at ${\geq}0.4{\mu}g/100cm^2$ as measured by a wipe test of a nonporous surface and if it has at 0.04 mg/L as measured by cutting test of a porous material. Also, new analytical methods for PCBs containing solid waste were proposed.

• Journal of the Korean Society of Food Culture
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• v.22 no.2
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• pp.246-253
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• 2007

Mineral and volatile flavor compounds of Pimpinella brochycarpa N., a perennial Korean medicinal plant of the Umbelliferae family, were analyzed by inductively coupled plasma-atomic emission spectroscopy (ICP-AES) and simultaneous steam distillation extract (SDE)-gas chromatography mass spectrometry (GC/MS), head space solid phase micro-extraction (HS-SPME)-GC/MS. Mineral contents of the stalks and leaves were compared and the flavor patterns of the fresh and the shady air-dried samples were obtained by the electronic nose (EN) with 6 metal oxide sensors. Principal component analysis (PCA) was carried out using the data obtained from EN. The 1st principal values of the fresh samples have + values and the shady air-dried have - values. The essential oil extracted from the fresh and the shady air-dried by SDE method contain 58 and 31 flavor compounds. When HS-SPME method with CAR/PDMS fiber and PDMS fiber were used, 34 and 21 flavor compounds. The principal volatile components of Pimpinella brachycarpa N. were ${\alpha}$-selinene, germacrene D, and myrcene.