• Journal of the Korea Organic Resources Recycling Association
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• v.13 no.3
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• pp.71-81
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• 2005

Anaerobic digestion is employed worldwide as the oldest and most important process for sludge stabilization. An additional advantage is the production of methane during anaerobic digestion. However, the waste activated sludge(WAS) has poor anaerobic degradability and less gas production due to the cell wall of bio-solid. In order to improve and enhance stabilization and dewatering of the WAS, a number of pretreatment processes have been developed and investigated. In this research, a pilot-scale study of pulse power pretreatment was performed to improve anaerobic degradability and dewaterability of the WAS. A pilot plant was designed and operated based on a previous laboratory study. Change of the sludge characteristics by pulse power pretreatment was estimated to assess the increasing soluble organics. The increased soluble organics could be used as a good substrate in the anaerobic digesion process. Gas production and methane potential of the anaerobic digestion were estimated as the parameters of anaerobic degradability. For evaluation of the dewaterability of pretreated WAS, capillary suction time(CST) and specific resistance were measured. The efficiency of energy recovery was also estimated by calculating energy balance.

• The Korean Journal of Pesticide Science
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• v.4 no.2
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• pp.1-10
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• 2000

Fungicide resistance study in Korea is still in its infancy, and most of those resistance studies are largely limited to newness of the detected resistant strains. In future, detection of fungicide-resistant strains has to be based on sensitivity distribution of pathogen populations to certain fungicides, and standard levels of certain fungicides for resistance should be determined under the basis of this data. Most of the early research on fungicide resistance in Korea has overlooked this point, and resulted in inconsistency and confusion for monitoring sensitivity shift of pathogen population among individual researchers. Fungicide resistance detected in vitro tests has to be documented in field trials by examining control efficacy against resistant and wild-type pathogen populations. Resistance detection in wife has to be correlated with lower activity in practice. Using this process, fungicide resistance will have a practical meaning. Fitness evaluation of resistant strains for survival is, in particular, of importance to determine the future stability of the resistance in the pathogen population. In fields, sensitivity change of pathogen populations should be carefully monitored with and without fungicide selection pressures to establish long-term management strategies against fungicide resistance. It is becoming an urgent task to provide information through research for designing and implementing successful counter-measures against fungicide resistance problems in Korea.

• Journal of the Korean Applied Science and Technology
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• v.36 no.4
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• pp.1208-1218
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• 2019

The study is on the cosmetic solubilizing power of organic plant surfactants. The blended high purity polyglyceryl-10 oleate and polyglyceryl-10 stearate mixtures were synthesized using organically certified raw materials to develop surfactants having excellent solubilizing power. The mixture is called "Solubil ORG-1300". The appearance of this material is a pale yellowish paste, with a specific odor. The specific gravity was 1.12 and it was high purity that acid value was 0.072±0.1. The HLB value of this natural surfactant was averaged = 15.1 and calculated through the Griffin equation. Mechanically it is explained how organic surfactant are available with fragrance and oils. The solubilizing test was determined by eye evaluation method through the dissolving performance test for the two oils and measured the transmittance at 890 nm using a UV spectrophotometer to measure the transparency. The results showed that the concentration of surfactant needed to make Bergamot oil available requires approximately more 2 times. It was also found that the concentration of surfactant needed to make the tocoperyl acetate available was about 8 times higher. Experiments on the solubility resulting from pH changes showed stabilized usable solubilizing power even in acidic areas of pH=3.5, neutral areas of pH=7.2, and alkaline areas of pH=1.5. Experiments on the solubility according to pH variation showed good solubility stabilized in acidic areas of pH=3.5, neutral areas of pH=7.2, and alkaline areas of pH=11.5. As an application of cosmetics, the company successfully developed a prescription for moisturizing activity based on these results, it is expected that a wide range of applications will be available for skin care, baby lotion, sensitivity or atopic skin cosmetics.

• Resources Recycling
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• v.9 no.1
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• pp.36-43
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• 2000

This study was carried out for treatment and reuse of inorganic sludge from Fenton process at B dyeing wastewater treatment plant. The parameters for pilot-scale treatment system were derived from the results of this study. It was found that $COD_{cl}$ of the treated effluent became lower than 100 mg/l approximately on the optimal reaction condition. 2nd sludge which was generated after redissolving sludge was analyzed, and it showed that reduction ratio of ash in 2nd sludge and total dry sludge weight in comparison with current sludge were 85% and 65%. Also Fe salt in sludge was redissolved about 90~95% of initial Fe by weight. It was estimated almost ￦350,000,000 for sludge reuse process. It was estimated saving of about ￦1,300,000 per day (￦420,000,000 per year) in operating cost based on 30,000 $m^3$/d treatment, which these were about ￦430,000 per day in chemical, ￦1,100,000 per day in sludge transportation and ￦200,000 per day in equipment maintenance. Payback period with interest charge for investment cost was estimated about 10.5 months. Also, net present value (NPV) was ￦792,000,000 and internal rat of return (IRR) was about 110%.

• Korean Security Journal
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• no.62
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• pp.87-111
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• 2020

Special security guards working at nuclear power plants, one of the country's major facilities, serve as human protection to safeguard from threats to nuclear facilities and nuclear materials. The purpose of this study was to develop a physical fitness program for fitness management that is essential for the completion of missions of special guards. This program was designed to prepare the physical fitness test proposed by Jeong et al. (2019). Researchers conducted literature analysis, research meetings, expert meetings and pretests, and developed a 90-minute physical fitness program for 6 weeks, 3 times a week. In order to verify the effectiveness of the developed physical fitness program, the experiment was conducted on 29 subjects(control group: 15, exercise group:14). Specifically, a six-week physical fitness program was conducted for exercise groups, and the fitness test for a special security guard was conducted for all subjects before and after the experiment. As a result, it was found that the physical fitness program was effective in improving the performance of 20m shuttle run, leg tuck, 20m sprint & carry, and medicine ball back throw. Until recently, problems of neglecting fitness management of security guards have been pointed out. It is expected that the physical fitness program proposed by this study will be a practical alternative for security guards' fitness management.

• Food Science and Preservation
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• v.22 no.4
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• pp.585-590
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• 2015

As consumers are aware of their health and are more conscious of environmental conditions, there is an increasing demand for organic agri-foods. The present study aims to investigate the physicochemical quality characteristics and antioxidant activity of organic green peppers. The weight, length, moisture content, color (Hunter L, a, b) and hardness were measured for the quality characteristics. In addition, the DPPH, ABTS radical scavenging activities and total phenolic contents were analyzed for the comparison of antioxidant activities between organically and conventionally grown green peppers. The weight and length of the organically grown green peppers were lower than those of the conventionally grown ones. The moisture content of the organically and conventionally grown green peppers was similar. The L and b values of the organically grown green peppers were higher than those of the conventionally grown ones. The DPPH radical scavenging activity of the organically grown green peppers (62.86%) was higher than that of the conventionally grown ones (51.06%). The total phenolic content of the organically grown green peppers was higher than that of the conventionally grown ones, however, there was no significant differences between organically and conventionally grown green peppers (p<0.05). Further studies would be recommended for the evaluation of other characteristics such as flavor, taste, and bioactivity compounds between organically and conventionally grown green peppers.

• Korean Journal of Plant Resources
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• v.26 no.1
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• pp.84-89
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• 2013

We established that regenerated plants of Panax ginseng were directly transplanted into the soil without the acclimatization process. When regenerated plants were treated at the concentration of $0.4mg\;l^{-1}$ for 9 hr before transplantation into the soil, our results showed that the survival rate of them was the highest. The optimal size of the root was above 4 cm in length and 0.4 g by weight before transplantation into the soil. The highest survival rate increased to 59.6%. After 4 years of cultivation in the fields, our results showed that there were no significant morphological differences between regenerated plants and wild-type ginseng. Also, we obtained healthy seeds from regenerated plants. This study provides the basis for a relatively rapid multiplication of selected genotypes and will allow a much more rapid evaluation of the germplasm of the unexplored and unstudied Korean ginseng.

• Korean Journal of Medicinal Crop Science
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• v.20 no.4
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• pp.277-285
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• 2012

In this study, Expressed Sequence Tag-Simple Sequence Repeat (EST-SSR) analyses were used to clarify the genetic polymorphisms among Korean ginseng cultivars and breeding lines and to classify them into distinct genetic groups. Polymorphic and reproducible bands were produced by 14 primers out of total 30 primers used in this study. Fourteen EST-SSR loci generated a total of 123 bands. Amplified PCR products showed the highly reproducible banding patterns at 110~920 bp. The number of amplified bands for each EST-SSR primers ranged from 2 to 19 with a mean of 8.8 bands. P26 and P35 primers showed 13 and 12 banding patterns, respectively. The number of alleles for each EST-SSR locus ranged from 1.67 to 2.00 with a mean of 1.878 alleles. P34 and P60 primers showed the highest and the lowest genetic polymorphism, respectively. Cluster analysis based on genetic similarity estimated by EST-SSR markers classified Korean cultivars and breeding lines into 4 groups. Group included Gopoong and Chunpoong and 9 breeding lines (55%), group included 2 breeding lines (10%), group included 3 breeding lines (15%), group included Gumpoong and 3 breeding lines (20%). Consequently, the EST-SSR marker developed in this study may prove useful for the evaluation of genetic diversity and differentiation of Korean ginseng cultivars and breeding lines.

• Journal of Life Science
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• v.19 no.9
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• pp.1245-1250
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• 2009

Beimu (Fritillaria thunbergii Miquel), a bulbous plant of Liliaceae found in Korea, Japan and China, has been used as an antitussive and expectorant agent, and is also useful in alleviating stonsillitis and bronchiolitis. Most researches have been focused on micro-propagation and plant regeneration, component analysis, and dormancy relieving of beimu. Reports regarding the biological activity of beimu, such as anti-Helicobacter pyroli or platelet aggregation inhibition activity, are few and not widely available. In this study, methanol extract and its organic solvent fractions were prepared from Fritillaria thunbergii Miquel and their antimicrobial, antithrombin, and antioxidant activities were evaluated, respectively. The methanol extract contained lots of water-soluble materials (58.98%) and hexane-soluble oils (14.85%). The ethylacetate and butanol fraction at $500{\mu}g$/disc concentration showed strong antibacterial activity against tested bacteria, except Escherichia coli. Antifungal activity was not observed in methanol extract and its fractions. The hexane, ethylacetate and butanol fractions showed strong antithrombin activity at 4.8 mg/ml concentration. Especially, the ethylacetate fraction showed 95.4 sec of thrombin time at a concentration of 1.2 mg/ml, which is comparable to aspirin, a widely used antithrombosis agent. For antioxidation activity, the ethylacetate and butanol fraction showed good 1,1-diphenyl-2-picryl hydrazyl scavenging activity ($IC_{50}$ of $344{\sim}368{\mu}g$/ml). In superoxide dismutase-like activity and reducing power, the fractions showed $20{\sim}25%$ of vitamin C, and $51{\sim}54%$ of butyl hydroxytoluene, respectively.

• Korean Journal of Construction Engineering and Management
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• v.16 no.5
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• pp.65-76
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• 2015

FEED (Front End Engineering and Design) is the key area that determines the competitiveness of procurement and construction in the EPC contracts especially in terms of the added value. Nevertheless, previous researches in FEED have been limited to the process and deliverable of design work or the particular management business function (e.g. System Engineering, collaboration, information etc.). In this context, the purpose of this study is to propose a comprehensive FEED structure and its functions from the project management perspective throughout the whole project life-cycle for thermal power plants. Proposed FEED business procedures are classified into three levels; First level is the classification of FEED business phases, the second level defines major FEED management functions, and the third level is detailed FEED functions. A survey using proposed FEED functions and assessment variable was conducted in order to analyze the current status and the areas for future improvement. It is expected that the proposed structure, functions, and evaluation methodology for FEED management will contribute to effective practice of FEED as well as to improvement of competitive capability for engineering, procurement, and construction (EPC) companies.