• Journal of Climate Change Research
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• v.3 no.3
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• pp.211-224
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• 2012

Technology for energy recovery from waste can reduce the greenhouse gas emissions. So recently, there are several companies using RDF, RPF, WCF instead of using only coal fuel and it's part of the fuel on the increase. In this study, we developed Wood chip fuel $CO_2$ emission factor through fuel analysis. It's moisture content is 23%, received net calorific value is 2,845 kcal/kg, and received basis carbon is 34%. The result of emission factor is $105ton\;CO_2/TJ$, it's 5.9% lower than 2006 IPCC guideline default factor $112ton\;CO_2/TJ$. The gross GHG(Greenhouse gases) emissions of plant A is $178,767ton\;CO_2 eq./yr$, and Net GHG emissions is $40,359ton\;CO_2 eq./yr$. Therefore, the reduction of GHG emissions is $138,408ton\;CO_2/yr$ through using WCF, and I accounts for 77% of all GHG emissions.

• Journal of Life Science
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• v.28 no.12
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• pp.1469-1476
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• 2018

Occurrence of the Warburg effect in solid tumors causes resistance to cancer chemotherapy, and targeting energy metabolisms such as aerobic glycolysis is a potential strategy for alternative treatment. Dichloroacetate (DCA), an inhibitor of pyruvate dehydrogenase kinase (PDK), shifts glucose metabolism from aerobic glycolysis to oxidative phosphorylation (OxPhos) in many cancers. In this study, we investigated the anticancer effect of DCA on a human anaplastic thyroid cancer (ATC) cell line, 8505C. We found that DCA selectively inhibits cell proliferation of the 8505C line but not of a normal thyroid line. In 8505C, the cell cycle was arrested at the G1/S phase with DCA treatment as a result of decreased antiapoptotic proteins such as $HIF1{\alpha}$, PDK1, and Bcl-2 and increased proapoptotic proteins such as Bax and p21. DCA treatment enhanced the production of reactive oxygen species which consequently induced cell cycle arrest and apoptosis. Interestingly, DCA treatment not only reduced lactate production but also increased the expression of sodium-iodine symporter, indicating that it restores the OxPhos of glucose metabolism and the iodine metabolism of the ATC. Taken together, our findings suggest that PDK inhibitors such as DCA could be useful anticancer drugs for the treatment of ATC and may also be helpful in combination with chemotherapy and radiotherapy.

• Journal of the Korean Electrochemical Society
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• v.21 no.4
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• pp.80-87
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• 2018

Safety issues in Li-ion battery system have been prime concerns, as demands for power supply device applicable to wearable device, electrical vehicles and energy storage system have increased. To solve safety problems, promising strategy is to replace organic liquid electrolyte with non-flammable solid electrolyte, leading to the development of all-solid-state battery. However, relative low conductivity and high resistance from rigid solid-solid interface hinder a wide application of solid electrolyte. Composite electrolytes composed of organic and inorganic parts could be alternative solution, which in turn bring about the increase of conductivity and conformal contact at physically rough interfaces. In our study, composite electrolytes were prepared by combining poly(ethylene oxide)(PEO) and $Li_7La_3Zr_2O_{12}$ (LLZO). The crystallinity, morphology and electrochemical performances were investigated with the control of LLZO contents from 0 wt% to 50 wt%. From the results, it is concluded that optimum content and uniform dispersion of LLZO in polymer matrix are significant to improve overall conductivity of composite electrolyte.

• Korean Journal of Remote Sensing
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• v.34 no.6_1
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• pp.1143-1153
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• 2018

For TOPS InSAR processing, high-precision image co-registration is required. We propose an image co-registration method suitable for the TOPS mode by comparing the performance of cross correlation method, the geometric co-registration and the enhanced spectral diversity (ESD) matching algorithm based on the spectral diversity (SD) on the Sentinel-1 TOPS mode image. Using 23 pairs of interferometric pairs generated from 25 Sentinel-1 TOPS images, we applied the cross correlation (CC), geometric correction with only orbit information (GC1), geometric correction combined with iterative cross-correlation (GC2, GC3, GC4), and ESD iteration (ESD_GC, ESD_1, ESD_2). The mean of co-registration errors in azimuth direction by cross correlation and geometric matching are 0.0041 pixels and 0.0016 pixels, respectively. Although the ESD method shows the most accurate result with the error of less than 0.0005 pixels, the error of geometric co-registration is reduced to 0.001 pixels by repetition through additional cross correlation matching between the reference and resampled slave image. The ESD method is not applicable when the coherence of the burst overlap areas is low. Therefore, the geometric co-registration method through iterative processing is a suitable alternative for time series analysis using multiple SAR data or generating interferogram with long time intervals.

• Journal of Animal Science and Technology
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• v.61 no.4
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• pp.216-224
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• 2019

This study was conducted to investigate the effects of hot melt extrusion (HME) nano-iron as an alternative for the common ferrous sulfate on iron (Fe) bioavailability, growth performance, nutrient digestibility, intestinal morphology, and intestinal microbiota of weanling pigs. A total of 200 piglets (Landrace ${\times}$ Yorkshire ${\times}$ Duroc) were randomly allotted to seven treatments on the basis of initial body weight (BW) and sex. Treatments were the INO100 (100 ppm Fe as $FeSO_4$), HME-Fe levels (50, 75, and 100 ppm nano-Fe as $FeSO_4$). ORG100 (100 ppm Fe as iron methionine). In phase 1, the HME50 pigs showed the lowest Fe content in feed and feces. Plasma Fe concentration was increased in HME100 and ORG100 pigs. In phase 2, there were significantly lower concentration of Fe in feed and feces of HME50 pigs (p < 0.01). A lower Fe concentration in the plasma and liver were observed in HME50 pigs compared with HME100 pigs. Concentration of red blood cell (RBC) was the lowest (p < 0.01) for HME50 pigs. During phase 2, the HME100, HME75, and ORG100 pigs showed a higher RBC and hemoglobin values compared with HME50 pigs. Digestibility of gross energy (GE) and crude protein (CP) were significantly higher in HME100 pigs compared with HME50 pigs. There was an increased (p < 0.01) villus height in the duodenum and jejunum of HME100 pigs compared with HME50 pigs. It is concluded that dietary Fe does not improve growth performance of weanling pigs; however, increasing the dietary iron concentration in weanling piglets increased the RBC and hemoglobin. In addition, the potential ability of HME to be used at a lower level (HME75) was observed.

• Korean Journal of Microbiology
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• v.55 no.3
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• pp.206-212
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• 2019

Propionibacterium acnes (P. acnes) lives in the hair follicles and pores, and it uses cell debris, sebum and metabolic byproducts of surrounding skin tissues as energy and nutrients. Increased production of sebum due to sebaceous hyperplasia or blockage of the follicle can cause growth and proliferation of P. acnes. The rapid growth of P. acnes in follicles produces cell damage, metabolic byproducts and bacterial chips, which can cause inflammation. In this study, we examined the possibility of Senecio iscoensis Hieron. (S. iscoensis) extract to regulate P. acnes-induced inflammatory signaling pathways. We observed that S. iscoensis extract effectively inhibited P. acnes-induced pro-inflammatory cytokine expressions such as IL-$1{\beta}$, TNF-${\alpha}$, and iNOS in mouse macrophage cell line Raw 264.7. The inhibitory effect of S. iscoensis in pro-inflammatory cytokine levels was accompanied by the inhibition of the transcription factors NF-${\kappa}B$ and NF-AT. However, S. iscoensis did not alter the P. acnes-induced MAPK signaling pathways. This study first suggests the potential of using S. iscoensis extract as an alternative agent for the treatment of acne.

• Composites Research
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• v.32 no.5
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• pp.284-289
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• 2019

In the present paper, the dynamic force-moment equilibrium equations, driving power and energy equations are analyzed to formulate the equation for fuel economy(km/liter) equivalent to the driving distance (km) divided by the fuel volume (liter) of the vehicle, a selected model of gasoline powered KIA K3 (1.6v). In addition, the effects of the dynamic parameters such as speed of vehicle (V), vehicle total weight(M), rolling resistance ($C_r$) between tires and road surface, inclined angle of road (${\theta}$), as well as the aerodynamic parameters such as drag coefficient ($C_d$) of vehicle, air density(${\rho}$), cross-sectional area (A) of vehicle, wind speed ($V_w$) have been analyzed. And the possibility of alternative materials such as lightweight metal alloys, fiber reinforced plastic composite materials to replace the conventional steel and casting iron materials and to reduce the weight of the vehicle has been investigated by Ashby's material index method. Through studies, the following results were obtained. The most influencing parameters on the fuel economy at high speed zone (100 km/h) were V, the aerodynamic parameters such as $C_d$, A, ${\rho}$, and $C_r$ and M. While at low speed zone (60 km/h), they are, in magnitude order, dynamic parameters such as V, M, $C_r$ and aerodynamic ones such as $C_d$, A, and ${\rho}$, respectively.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.4
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• pp.590-596
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• 2019

Uses of fossil fuels like coal and oil increases with industrial development, and problems like abnormal climate come up as greenhouse gas increases. Accordingly, studies are actively conducted on eco-friendly renewable energy as a replacement for the main resources, and especially, wood pellets with high thermal efficiency are in the limelight as an alternative fuel in thermal power stations and gas boilers. However, despite a constant increase in their usage, few studies are conducted on their risks like fire and spontaneous combustion. Thus, this study found the auto-ignition temperature and critical ignition temperature of wood pellets with a change in flow rate in a thermostatic bath, using a sample vessel with 20 cm in length, 20 cm in height and 14 cm in thickness to predict their ignition characteristics. Consequently, at the flow rate of 0 NL/min, as the core temperature of the sample increased to higher than the ambient temperature, they ignited at $153^{\circ}C$, when the critical ignition temperature was $152.5^{\circ}C$. At the flow rates of 0.5 NL/min and 1.0 NL/min, it was $149.5^{\circ}C$, and at the flow rate of 1.5 NL/min, it was $147.5^{\circ}C$. Consequently, at the same storage, the more the flow rate, the lower the critical ignition temperature became.

• Journal of The Korean Society of Emergency Medicine
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• v.29 no.6
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• pp.649-655
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• 2018

Objective: This paper reports the possibility of using of a locking horizontal mattress suture technique in repairing lacerations that are difficult to suture with staples. Methods: Data were collected retrospectively over a 6-month period regarding the routine repair of scalp lacerations: those in areas injured by a high energy blunt mechanism, continued to bleed after pressure, nonlinear or damaged skin repaired with a locking horizontal mattress technique, and simple interrupted technique. The effects of the two techniques used to repair scalp lacerations on wound healing, complication rate, and patient satisfaction were examined. The categorical variables are expressed as the number and percent. A Mann-Whitney-Wilcoxon test was used for statistical analysis. A P-value less than 0.05 was considered significant. Results: Thirty-seven consecutive patients with scalp lacerations presented for care. Wound closure was accomplished with the locking horizontal mattress sutures in 40.5% (n=15) (median length, 5.0 cm; interquartile range [IQR], 4.0-7.0 cm). Simple interrupted sutures (median length, 4 cm; IQR, 3.0-5.0 cm) were used in 59.5% (n=22) (P=0.015). The frequency of additional bandage compression (P=0.008), frequency of exudative hemorrhage (P=0.018), and suture mark frequency at suture removal (P=0.047) were significantly lower in the locking horizontal mattress group. Conclusion: The locking horizontal mattress suture, which has the advantage of a horizontal mattress suture, may be one of the ways that can be used alternatively to treat scalp lacerations that difficult to suture with staples.

• Clean Technology
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• v.27 no.3
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• pp.269-274
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• 2021

Bioenergy is generally considered to be one of the options for pursuing carbon neutrality. However, for a period of time, combustion of harvested plant biomass inevitably causes more carbon dioxide in the atmosphere than combustion of fossil fuels. This paper proposes a method that predicts and minimizes the total amount and payback period of this carbon debt. As a case study, a carbon cycle impact assessment was performed for immediate switching of the currently used fossil fuels to biomass. This work points out a fundamental vulnerability in the concept of carbon neutrality. As an action plan for the sustainability of bioenergy, formulas for afforestation proportional to the decrease in the forest area and surplus harvest proportional to the increase in the forest mass are proposed. The results of optimization indicate that the carbon debt payback period is about 70 years, and the carbon dioxide in the atmosphere increases by more than 50% at a maximum and 3% at a steady state. These are theoretically predicted best results, which are expected to be worse in reality. Therefore, biomass is not truly carbon neutral, and it is inappropriate as an energy source alternative to fossil fuels. The method proposed in this work is expected to be able to contribute to the approach to carbon neutrality by minimizing present and future carbon debt of the bioenergy that is already in use.