• Korean Journal of Food Science and Technology
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• v.35 no.1
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• pp.15-22
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• 2003

Nutritional compositions of three Tochukaso species (Paecilomyces tenuipes hosted by Larva and pupa, Cordyceps militaris, C. sinensis) were compared. Fruiting body and host fractions were separately analyzed. Fruiting body fraction of P. tenuipes (36.6%) hosted by larva was higher than that hosted by pupa (10.2%), an indication that the quality of the former is superior to the latter. Carbohydrate content of C. sinensis (39.6%) was $2.5{\sim}7$ times higher than those of others, probably due to the presence of polysaccharides. Protein and crude lipid contents of C. sinensis and C. militaris were 25.8 and 10.3%, and 75.1 and 3.9%, respectively. C. sinensis showed the lowest Ca content and $30{\sim}75$ times higher Fe content among the samples tested. Vitamin A content of C. militaris was 308.9 IU/100g, two fold higher than those of the other species. Saturated fatty acid content was the highest in P. tenuipes (pupa, 27.7%), whereas unsaturated fatty acid was the highest in P. tenuipes (larva, 83.3%). Aspartic acid, glutamic acid, and glycine were abundant in all species. Cordycepin content of C. militaris was $20{\sim}50$ times higher than those of the other species.

• Journal of the Korean Society for Marine Environment & Energy
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• v.9 no.1
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• pp.14-20
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• 2006

In this study, the feasibility of simultaneous removal of organic materials and nitrogen in the waste-water from fisheries processing plant was evaluated using entrapped mixed microbial cell technique(EMMC) process. The experiment was performed using activated sludge from municipal sewage treatment plant which was immobilized with gel matrix by cellulose triacetate. It was found that the stable operation at the treatment system which is composed of anoxic and oxic tank, was possible when the organic and nitrogen loading rates were increased stepwise. The organic and nitrogen loading rates were applied from 0.65 to $1.72kgCOD/m^3/d$ and from 0.119 to $0.317kgT-N/m^3$ with four steps, respectively. The maximum nitrogen loading rate which could satisfy the regulated effluent standard of nitrogen concentration, was $0.3kgT-N/m^3/d$. The removal efficiency of total nitrogen was decreased apparently as increasing nitrogen loading rates, whereas the removal efficiency of ammonium nitrogen was effective at the all tested nitrogen loading rates. Therefore, it was concluded that nitrification was efficient at the system. Nitrate removal efficiency ranged from 98.62% to 99.51%, whereas the nitrification efficiency at the oxic tank ranged 94.0% to 96.9% at the tested loading rates. The removal efficiencies of chemical oxygen demand(COD) and those of total nitrogen at the entire system ranged from 94.2% to 96.6% and 73.4% to 83.4%, respectively.

• Journal of Korean Society of Environmental Engineers
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• v.35 no.3
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• pp.171-178
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• 2013

In this study, the sludge that occurs in the initial operation of coagulation system developed for the treatment of CSOs were returned to the flocculation reactor. The purposes of this study were to analyze the Characteristics of flocs that are generated through the recycling sludge and settling characteristics of sludge, and to evaluate the possibility that high concentrations of particulate matter in the initial inflow of CSOs could be used as an weighted coagulant additive. As a result, the concentration of treated CSOs pollutants at the beginning of the CSOs influent with a large amount of particulate matter over 20 ${\mu}m$ was low, after gradually increasing the concentrations of them. The flocs generated from the sludge return were similar in size compared to flocs generated through injection of micro sands, and settling velocity in case of return sludge injection was decreased from 55.1 cm/min to 21.5 cm/min. SVI value of the sludge accumulated at the bottom of the sedimentation tank was 72, and settled sludge volume decreased rapidly due to the consolidation of sludge to the time it takes to 10 minutes. these mean that sludge used for recycling has good settling characteristic. A condition of returned sludge which is 0.1% return of 0.3% extraction was formed in the balance of settlement and extraction. In this case, This condition was to be adequate to maintain the proper concentration such as 100~200 mg/L of TS and 50~100 mg/L of VS in the flocculation reactor. The usage of the return sludge containing particulate matters of CSOs as an weighted coagulant additive was able to secure a stable treated water quality despite the change of influent water quality dynamically. Furthermore, it can be expected to reduce the alum dosage along with the sludge production.

• Journal of the East Asian Society of Dietary Life
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• v.18 no.5
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• pp.812-821
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• 2008

The characteristics of cold-pressed sesame oil (CPSO), virgin sesame oil (VSO), commercial heat-press extracted sesame oil (CHPESO) and commercial supercritical fluid extracted sesame oil (CSFESO) were investigated. The total phenolics of CPSO, VSO, CHPESO and CSFESO were 31.27, 68.33, 60.65 and 31.44 mg/100 g, respectively. Their $\gamma$-tocopherol contents were 32.82, 31.66, 29.26 and 26.87 mg/100g, respectively. The sesamol, sesamin, and sesamolin contents of VSO were the highest. The oxidation induction period (4.53 hr) of CPSO was lower than that of VSO, CHPESO and CSFESO (19.90, 16.50, and 12.23 hr, respectively). CPSO was rapidly oxidized during storage at $60^{\circ}C$ in the dark, and its peroxide value (POV) was increased about 14 times. Although there were few differences in electron-donating abilities at low concentrations (below 100 mg%), VSO showed the highest electron-donating abilities at higher concentrations (77.76% at 10,000 mg%). Contents of linolenic acid and oleic acid were $40.35{\sim}43.98$ and $31.59{\sim}33.46\;g$/100 g, respectively. CPSO contained the highest amount of oleic and linoleic acid among the variously extracted sesame oil.

• Journal of the Korean Society of Marine Environment & Safety
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• v.25 no.7
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• pp.906-913
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• 2019

To evaluate the removal performance of PO₄-P and NH₃-N, laboratory experiments were conducted by filling a container with oyster shells, pyrolyzed at 100℃ (POS100), 600℃ (POS600) and 800℃ (POS800), and passing artificial wastewaters through the container. The pH in the ef luent was found to increase due to CaO eluted from oyster shell. Removal amounts of PO₄-P of ~23.1 mg/kg, 16.1 mg/kg, and 15.9 mg/kg were obtained when POS100, POS600, and POS800, respectively, were used; therefore, the highest PO₄-P removal amount was obtained when POS100 was used. It is considered that Ca and dolomite in the oyster shells adsorbed and precipitated PO₄-P. Removal amounts of NH₃-N were of ~3.56 mg/kg, 5.72 mg/kg, and 3.97 mg/kg were obtained when POS100, POS600, and POS800, respectively, were used The low removal rate for NH₃-N is probably due to unstable nitrification, use of sealed containers, and the effect of NH₃-N being converted to NH₄⁺ upon increasing pH. Based on these results, pyrolyzed oyster shell is expected to promote changes in PO₄-P and NH₃-N concentrations through chemical reactions. These results can also be used for basic research in the development of wastewater treatment.

• Fire Science and Engineering
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• v.31 no.5
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• pp.53-62
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• 2017

Electric power which is the energy source of economy and industries requires long distance transportation due to regional difference between its production and consumption, and it is supplied through the multi-loop transmission and distribution system. Prior to its actual use, electric power flows through several transformations by voltage transformers in substations depending on the characteristics of each usage, and a transformer has the structure consisting of the main body, winding wire, insulating oil and bushings. A transformer fire that breaks out in substations entails the primary damage that interrupts the power supply to houses and commercial facilities and causes various safety accidents as well as the secondary economic losses. It is considered that causes of such fire include the leak of insulating oil resulting from the destruction of bottom part of bushings, and the chain reaction of fire due to insulating oil that reaches its ignition point within 1 second. The smoke detector and automatic fire extinguishing system are established in order to minimize fire damage, but a difficulty in securing golden time for extinguishing fire due to delay in the operation of detector and release of gas from the extinguishing system has become a problem. Accordingly, this study was carried out according to needs of active mechanism to prevent the spread of fire and block the leak of insulating oil, in accordance with the importance of securing golden time in extinguishing a fire in its early stage. A bushings fireproof structure was developed by applying the high temperature shape retention materials, which are expanded by flame, and mechanical flame cutoff devices. The bushings fireproof structure was installed on the transformer model produced by applying the actual standards of bushings and flange, and the full scale fire test was carried out. It was confirmed that the bushings fireproof structure operated at accurate position and height within 3 seconds from the flame initiation. It is considered that it could block the spread of flame effectively in the event of actual transformer fire.

• Journal of Korea Water Resources Association
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• v.52 no.1
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• pp.51-60
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• 2019

The major purpose of this study is to construct an in-situ soil moisture verification network employing Frequency Domain Reflectometry (FDR) sensors for Cosmic-ray soil moisture observation system operation as well as long-term field-scale soil moisture monitoring. The test bed of Cosmic-ray and FDR verification network system was established at the Sulma Catchment, in connection with the existing instrumentations for integrated data provision of various hydrologic variables. This test bed includes one Cosmic-ray Neutron Probe (CRNP) and ten FDR stations with four different measurement depths (10 cm, 20 cm, 30 cm, and 40 cm) at each station, and has been operating since July 2018. Furthermore, to assess the reliability of the in-situ verification network, the volumetric water content data measured by FDR sensors were compared to those calculated through the core sampling method. The evaluation results of FDR sensors- measured soil moisture against sampling method during the study period indicated a reasonable agreement, with average values of $bias=-0.03m^3/m^3$ and RMSE $0.03m^3/m^3$, revealing that this FDR network is adequate to provide long-term reliable field-scale soil moisture monitoring at Sulmacheon basin. In addition, soil moisture time series observed at all FDR stations during the study period generally respond well to the rainfall events; and at some locations, the characteristics of rainfall water intercepted by canopy were also identified. The Temporal Stability Analysis (TSA) was performed for all FDR stations located within the CRNP footprint at each measurement depth to determine the representative locations for field-average soil moisture at different soil profiles of the verification network. The TSA results showed that superior performances were obtained at FDR 5 for 10 cm depth, FDR 8 for 20 cm depth, FDR2 for 30 cm depth, and FDR1 for 40 cm depth, respectively; demonstrating that those aforementioned stations can be regarded as temporal stable locations to represent field mean soil moisture measurements at their corresponding measurement depths. Although the limit on study duration has been presented, the analysis results of this study can provide useful knowledge on soil moisture variability and stability at the test bed, as well as supporting the utilization of the Cosmic-ray observation system for long-term field-scale soil moisture monitoring.

• Ecology and Resilient Infrastructure
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• v.7 no.4
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• pp.262-273
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• 2020

Amending biopolymers such as β-glucan (BG) and Xanthan gum (XG) generally enhances soil strength by ionic and hydrogen bonds between soil particles. Thus, biopolymers have been studied as eco-friendly construction materials in levees. However, physiological responses of plants grown on soil amended with biopolymers are not fully understood. This study focuses on the effects of biopolymers on the growth of Camelina sativa L. (Camelina) under excess zinc (Zn) stress. The optimal concentrations of BG and XG were confirmed to have a 0.5% ratio in soil depending on the physiological parameters of Camelina under excess Zn stress. The Zn binding capacity of biopolymers was investigated using 1,5-diphenylthiocarbazone (DTZ). The reduction of Zn damage in Camelina was evaluated by analyzing the Zn content and expression of heavy metal ATPase (HMA) genes under excess Zn stress. Amendments of BG and XG improved Camelina growth under excess Zn stress. In DTZ staining and ICP-OES analysis, Camelina grown on BG and XG soil showed less Zn uptake than normal soil under excess Zn stress. The Zn-inducible CsHMA3 gene was not stimulated by either BG or XG amendment under excess Zn stress. Moreover, both BG and XG amendments in soil exhibit Zn-stress mitigation similar to that of Zn-tolerant CsHMA3 overexpres sed Camelina. These results indicate that biopolymer-amended soils may influence the prevention of Zn absorption in Camelina under excess Zn stress. Thus, BG and XG are proven to be suitable materials for levee construction and can protect plants from soil contamination by Zn.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.22 no.2
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• pp.139-147
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• 2021

Livestock manure is used as an organic fertilizer to replace chemical fertilizers after sufficient fermentation in an aerobic bioreactor. On the other hand, liquid manure disposal problems occur repeatedly because soil spraying is restricted during the summer when the crops are growing. To use liquid fertilizer (LF) as an additional nutrient source for crops, it is necessary to reduce the amount of suspended solids (SS) in the liquid fertilizer and secure stability problems against pathogenic microorganisms. This study examined the effects of the simultaneous SS removal and E.coli sterilization in the LF using the microbubble (MB) generator (FeMgO catalyst insertion). The remaining SS were further removed using the integrated microbubble and microfilter system. During the floating process in the MB device, the SS were removed by 57.9%, and the coliform group was not detected (16,200→0 MPN/100 mL). By optimizing the HRT of the integrated system, the removal efficiency of the SS was improved by 92.9% under the 0.1h of HRT condition. After checking the properties of the treated LF, 64.5%, 70.1%, 54.9%, and 51.5% of the TCOD, SCOD, PO4-P, and TN, respectively, were removed. The treated effluent from such an integrated system has a lower SS content than that of the existing LF and does not contain coliforms; therefore, it can be used directly as an additional fertilizer.

• Clean Technology
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• v.28 no.1
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• pp.63-78
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• 2022

Electronics industrial wastewater treatment facilities release organic wastewaters containing high concentrations of organic pollutants and more than 20 toxic non-biodegradable pollutants. One of the major challenges of the fourth industrial revolution era for the electronics industry is how to treat electronics industrial wastewater efficiently. Therefore, it is necessary to develop an electronics industrial wastewater modeling technique that can evaluate the removal efficiency of organic pollutants, such as chemical oxygen demand (COD), total nitrogen (TN), total phosphorous (TP), and tetramethylammonium hydroxide (TMAH), by digital twinning an electronics industrial organic wastewater treatment facility in a cyber physical system (CPS). In this study, an electronics industrial wastewater activated sludge model (e-ASM) was developed based on the theoretical reaction rates for the removal mechanisms of electronics industrial wastewater considering the growth and decay of micro-organisms. The developed e-ASM can model complex biological removal mechanisms, such as the inhibition of nitrification micro-organisms by non-biodegradable organic pollutants including TMAH, as well as the oxidation, nitrification, and denitrification processes. The proposed e-ASM can be implemented as a Water Digital Twin for real electronics industrial wastewater treatment systems and be utilized for process modeling, effluent quality prediction, process selection, and design efficiency across varying influent characteristics on a CPS.