• Food Science and Preservation
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• v.31 no.4
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• pp.673-681
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• 2024

This study was conducted to develop kombucha with better functionality. The developed kombucha (CK) was prepared using the sugar extracts from fruits of Cudrania tricuspidata (Carrière) Bureau ex Lavallée instead of the sugar, which is used as a substrate for SCOBY in conventional kombucha (K). During fermentation, the soluble solids content significantly decreased in CK compared to K, and the pH change decreased rapidly in CK compared to K. On the 14^th day of fermentation, the weight of the SCOBY in CK was higher than that in K. Immediately after preparation, K contained only sucrose, but CK contained sucrose, glucose, and fructose. SCOBY appears to use glucose and fructose preferentially during fermentation. K contained acetic acid and citric acid right after preparation. However, as fermentation progressed, the composition changed to acetic acid, citric acid, and lactic acid. At the same time, CK initially consisted of citric acid, lactic acid, and acetic acid. However, acetic acid and citric acid increased but lactic acid decreased significantly on the 14^th day of fermentation. In the cytotoxicity studies, the CK showed a proliferation-promoting effect on normal lung cells (MRC-5) and strong cytotoxicity against human lung cancer cells (A549). These results suggest that the kombucha made from sugar extracts of C. tricuspidata fruits can be used as a more functional beverage than regular kombucha.

• Journal of the Korea Organic Resources Recycling Association
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• v.17 no.1
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• pp.27-38
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• 2009

To investigate the feasibility of refuse derived fuels (RDFs) combined of sewage sludge and combustible wastes such as substitutive fuels instead of a stone coal, several different RDFs made with different mixtures of sewage sludge and combustible wastes were analyzed by various experiments. The combustion characteristics for the RDFs were investigated by analyzing fuel gases, and heating values were also measured by a bomb calorimeter. The fundamental properties such as moisture contents, ratios of combustible materials, amounts of ashes, heavy metals, ratios of each chemical elements and heating values were analyzed in accordance with mixing ratios of wt(%) for researching the characteristics of the RDFs. $RDF_{k-1}$ was made of mixing materials which were dried sewage sludge, food wastes and combustible wastes. $RDF_{k-2}$ was made of mixing materials which were peat-moss, tar and sewage sludge. Combustion experiments were carried out at the optimal conditions which were m=2 under air-fuel condition and $850^{\circ}C$. The retention times in the combustor were set at 5, 10 and 15minutes. 50 g of RDFs was put in the combustor for each experiments. The ranges for heating values of $RDF_{k-1}$ with different mixing ratios were from 6,900 kcal/kg to 8120 kcal/kg. The ranges for heating values of $RDF_{k-2}$ with different mixing ratios were from 4,014 kcal/kg to 8,050 kcal/kg. As a result of this study, the heating values, moisture contents, components of chemical elements and mixing ratios of the materials in RDFs had big effects on the efficiency of the combustion. In $RDF_{k-1}$, the higher amounts of combustible wastes in the mixtures, the higher heating values, concentrations of $C_xH_y$ and amounts of ashes were produced. In $RDF_{k-2}$, the higher tar amounts in the mixtures caused the higher heating values, amounts of ashes, concentrations of CO gas and CxHy.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.44 no.4
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• pp.519-529
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• 2024

Vehicle toll discounts on private roads are categorized into two types: non-sunset and sunset. Sunset types refer to provisions in which all or part of a law loses its effect upon a specific legislator-set deadline. Vehicles eligible for 'sunset' discounts include cargo vehicles operating late at night and eco-friendly vehicles powered by electricity or hydrogen. Korean government has subsidized all reduced toll fees for vehicles classified as non-sunset types on private roads to operators, but no subsidies have been provided for toll reductions on sunset vehicles. The rapid increase in electric hydrogen vehicles escalates the burden of reduced toll revenue on private road operators. This study analyzed traffic volume and toll reduction data from eight private road operators nationwide as of the end of 2023 to propose the necessity and method of supporting sunset-type toll reduction subsidies. In 2022, the subsidy for non-sunset types amounted to 87.5 billion won, or 18.6 % of total traffic revenue. The toll exemption and reduction ratio under the concession agreement ranged from 4.0 % to 5.65 % of total traffic volume for each operator. Although the proportion of vehicles exempted from sunset traffic increased from 0.85 % in 2017 to 2.79 % in 2022, the reduction amount ratio reached 4.2 % (KRW 25.5 billion) of total traffic revenue in 2022. The escalating number of registered eco-friendly vehicles is gradually causing operating profit losses on private roads. In alignment with the government's policy to expand eco-friendly vehicles, it is imperative to consider including vehicles eligible for toll reductions listed under the sunset category for subsidy payments. The study established a minimum ratio for toll reduction assistance at 4.0 %, agreed upon between the road authorities and private operators. Three policy alternatives were proposed to ensure preservation of amounts exceeding this threshold for sustaining adequate toll revenue for private road operators.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.69 no.2
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• pp.123-132
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• 2024

In this study, two types of biodegradable film prototypes were produced using plastic resin containing rice powder. The application of these biodegradable films in sweetpotato (Ipomoea batatas L. Lam) fields and their impacts of plant growth, yield, and the soil environment were assessed, in comparison with Polyethylene (PE) film. The light transmittance of the biodegradable film containing 30% of 350 mesh rice powder (BF30-350RP) was 0.8%, which was lower than the 2.0% light transmittance of the biodegradable film containing 40% of 500 mesh rice powder (BF40-500RP) and 2.7% light transmittance of PE film. Surface temperature measurements on clear day indicated that the PE film exhibited the lowest temperature, with the minimal difference observed between BF40-500RP and BF30-350RP. Assessment of the damage ratio resulting from agricultural work revealed a ranking of 0.4% for the PE film, 3.3% for BF500-400RP, and 5.3% for BF350-30RP. Visible decomposition of BF40-500RP and BF30-350RP commenced after 40 and 30 days of outdoor exposure, reaching 62.3% and 70.4% decomposition at 90 days post-exposure, respectively. The decomposition of biodegradable films applied to sweetpotato fields progressed more slowly in BF40-500RP than in BF30-350RP. The BF40-500RP film on the surface of the ridges was decomposed by 5%, 30%, 55%, and 90% after 30, 60, 90, and 120 days after planting sweetpotato cuttings, respectively. Both types of biodegradable films at the ridge and furrow borders were completely decomposed after 75 days of sweetpotato planting. In a field where the surface was sealed by mulching without growing sweetpotatoes, the soil moisture and its deviation were lower in the order of PE film, BF40-500RP, and BF30-350RP, but the differences were not significant. The soil temperature was higher for PE film mulching than for the biodegradable films containing rice powder, but the differences were small. Two months after sweetpotato planting, the daily average soil moisture decreased by 2.5%point for BF30-350RP mulching, 1.5%point for BF40-500RP mulching, and 1.1%point for PE film mulching over seven days. Soil temperature was similar for both biodegradable film mulches, but increased steadily for the PE film mulch, reaching a daily average of 0.1℃ higher than for the biodegradable films. Sweetpotato vine growth and tuber yield were similar for all the mulching films tested.

• Sim-seong Yeon-gu
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• v.39 no.1
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• pp.129-183
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• 2024

This study is an attempt to get closer to the psychological truth of alcohol addiction. After reviewing previous related studies, the experiences of Korean alcoholics were examined, encompassing both the conscious and unconscious aspects. In order to approach the unconscious, the researcher paid attention to the series of dreams that the patients reported, from the perspective of Jungian dream analysis. Working with dreams brought considerable benefits in increasing patient's involvement in the therapeutic process and fostering therapist-patient alliance. It also helped to understand patients' conscious and unconscious aspects further. The results were as follows. On the conscious level, patients showed a long-standing alienation from their true emotional needs, a lack of sufficient experience in genuinely expressing and being accepted with one's own emotion, resulting in the need for emotional re-experience, along with the intense longing for maternal affection. This also meant that they were in need for maternal re-experience, and at the same time, for the associated paternal re-experience. Furthermore, the researcher identified that certain powerful archetypal complexes had been activated in the patient's unconscious in response to their conscious situations, triggering the destructive shadows to emerge and exert a strong influence on their conscious lives. The series of reported dreams shows how the unconscious always properly and diligently compensates, modifying the perspective and attitude of the conscious and gradually opening the doors to healing, even for alcoholic patients. This indicates that the unconscious carries out a specific and consistent guidance role so the conscious can realize and adequately respond to it, and that it also provides the creative force for transforming the conscious life. These findings suggest that alcohol addiction is a psychological condition that can jeopardize one's life by allowing the powerful energy of the unconscious to penetrate the conscious, but at the same time, have the purpose and direction to urge the creative transformation of one's conscious life. From these results, it can be concluded that the first step towards true recovery is for the individual to turn their attention towards the psychological truth occurring within themselves. In this regard, the therapist's role is crucial. This also suggests that various attempts in the field of addiction treatment will blossom their real values when they contribute, directly or indirectly, to the development of one's self-awareness since as long as one continues to turn away from the psychological truth and persist in craving for false objects, their creative healing properties in the unconscious could rather have negative and destructive impacts on their life.

• Journal of Bio-Environment Control
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• v.32 no.4
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• pp.319-327
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• 2023

To harvest marketable cucumbers, high quality seedlings must be used. Producing seedlings in the greenhouse during the low radiation period decreases marketability due to insufficient light for growth. Supplemental lighting with artificial light of different quality can be used to improve low light conditions and produce high quality seedlings. Therefore, this study was conducted to select the appropriate supplemental light sources on the growth and seedling quality of grafted cucumber seedlings during the low radiation period. Three cultivars of cucumber were used as scions for grafting; 'NakWonSeongcheongjang', 'Sinsedae', and 'Goodmorning baekdadagi'. Figleaf gourd (Cucurbita ficifolia) 'Heukjong' was used as the rootstock. The seeds were sown on January 26, 2023, and grafted on February 9, 2023. After graft-taking, cucumbers in plug trays were treated with RB light-emitting diodes (LED, red and blue LED, red:blue = 8:2), W LED (white LED, R:G:B = 5:3:2), and HPS (high-pressure sodium lamp), respectively. Non-treatment was used as the control. Supplemental lighting was applied 2 hours before sunrise and 2 hours after sunset for 19 days. The stem diameter and fresh and dry weights of roots did not differ significantly by supplemental light sources. The plant height and hypocotyl length were decreased in W LED. However, the leaf length, leaf width, leaf area, and fresh and dry weights of shoots were the highest in the RB LED. Seedling qualities such as crop growth rate, net assimilation rate, and compactness were also increased in RB LED and W LED. After transplanting, most of the growth was not significant, but early yield of cucumber was higher in LED than non-treatment. In conclusion, using RB LED, W LED for supplemental light source during low radiation period in grafted cucumber seedlings improved growth, seedling quality, and early yield of cucumber.

• Journal of Bio-Environment Control
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• v.32 no.4
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• pp.257-266
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• 2023

This study was conducted to investigate the growth characteristics of cucumber (Cucumis sativus L. 'Joeunbaekdadagi') and tomato (Solanum lycopersicum L. 'Dotaerang Dia') seedlings by light intensities and CO₂ concentrations in a closed-type plant production system (CPPS). Cucumber and tomato seeds were sown in 50-cell trays and germinated in CPPS at air temperature 25 ± 1℃ and relative humidity 50 ± 10% for 4 days. After germination, the CO₂ concentrations and light intensity treatment were treated at 500 (ambient), 1,000, and 1,500 µmol·mol^-1 and 100, 200, and 300 µmol·m^-2·s^-1 photosynthetic photon flux density (PPFD), respectively. The leaf area of cucumber showed the highest value in CO₂ 1,500 μmol·mol^-1. However, the leaf area of the tomato had no significant difference in CO₂ concentrations and light intensities treatments. In cucumber and tomato both seedlings, the growth and quality such as compactness and leaf area rate were increased with the increase of light intensity, and there were highest in 300 µmol·m^-2·s^-1. The root surface and number of root tips of cucumber and tomato seedlings were significantly increased with the increase in light intensity. In conclusion, the regulation of the CO₂ concentrations and light intensity can control the growth and quality of cucumber and tomato seedlings in CPPS, especially, increasing the light intensity can improve more significantly the growth and quality of seedlings.

• Journal of Bio-Environment Control
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• v.33 no.1
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• pp.30-36
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• 2024

This study was conducted to determine the optimal working conditions when a recently developed blower-type onion stem cutter is utilized for cutting onion leaves at harvest time. The June 20 leaf cutting treatment group had the highest leaf dryness among the treatment groups (leaf dryness: 66.3%; leaf moisture content: 50.5%); the residual leaf length was 6.7 ± 3.5 cm. It is considered to have the best mechanical leaf cutting performance among the treatment groups because it is included in the optimal range of 4-10 cm. The average working speed of mechanical onion leaf cutting using the stem cutter was 0.17 m·s^-1, which is approximately 3.4 times faster than the average working speed of 0.05 m·s^-1 in the human leaf cutting treatment group. This is expected to save approximately 2.6 hours compared to human labor (based on one person) when working on a 10a area using this machine. In addition, the incidence of damaged bulbs in the machine leaf cutting treatment group was 1.3%, compared to 0.0% in the manual leaf cutting treatment group. This suggests that the mechanical leaf cutting treatment group had a higher average onion bulb decay rate during storage than the manual leaf cutting treatment group. When the storage characteristics of each treatment group were examined, the decay rate by bulb part (leaf connected or root connected) after 8 months of storage was higher in the treatment group with a residual leaf length of less than 5.0 cm after mechanical leaf cutting than in the treatment with a residual leaf length of more than 5.0 cm. This is thought to be due to the fact that treatments with a residual leaf length of less than 5.0 cm are more susceptible to infection by pathogens that cause decay during storage than treatments with a residual leaf length of 5.0 cm or more. Based on the results of this experiment, performance target of the experimental machine (residual leaf length after operation: 5 cm), and existing research on the optimal residual leaf length for onion harvesting, it is recommended to cut onion leaves so that the residual leaf length is 5-10 cm when using the stem cutter.

• Journal of Bio-Environment Control
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• v.33 no.1
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• pp.71-78
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• 2024

Among the various environmental conditions necessary for growing crops, light is closely related to the anthesis. This study aimed to determine the optimal photoperiod affecting floral differentiation in an edible flower, marigold, to efficiently cultivate the crops in a closed-type plant factory. The experiment was conducted with photoperiods of 4, 8, 12, and 16 hours. French marigold (Tagetes patula L.) 'Durango Red' seeds were sown in polyurethane sponges, and the photoperiod treatments were applied immediately. The extent of floral differentiation was examined at 2-3 day intervals, defined as the visible appearance of flower buds at least 2 mm in size. The growth parameters such as shoot fresh weight and dry weight, height, and leaf area were measured. The optimal photoperiod was determined based on the days when the floral differentiation had occurred in 50% of the total plants. In the 4-hour treatment, proper growth and flower buds did not appear. From the 8-hour treatment, the plant grew normally, and floral differentiation occurred, however, the 8-hour treatment showed the slowest floral differentiation compared to the 12 hours treatments or more. The 12- and 16-hour treatments didn't show significant differences in floral differentiation. While the 16-hour treatment exhibited the highest results in all growth parameters, it was not significantly different from the 12-hour treatment except for shoot dry weight and leaf area. According to the results, 8 hours of photoperiod induced floral differentiation. However, more time was required for flower bud formation, and plant growth was significantly lower compared to photoperiods of 12 hours or more. Considering the energy consumption and its growth, the optimal photoperiod for marigold was 12 hours.

• Journal of Bio-Environment Control
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• v.33 no.3
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• pp.163-171
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• 2024

This study was aimed to investigate the effects of layer-by-floor environmental conditions and lower shelf supplemental lighting on the productivity of fresh shoots when growing rosemary in multi-layer cultivation. The 10-cm cuttings from stock plants of common rosemary (Rosemarinus officinalis) were planted in a 128-hole tray, rooted, and then transplanted into pots of 750, 1,300, and 2,000 mL. Afterwards, they were placed on multi-layer shelves (width × length × height: 149 × 60 × 57 cm, 3-layer) in a two-linked greenhouse and cultivated using the sub-irrigation. The productivity of young shoots by layer of the multi-layer shelf was the highest on the third floor (top floor), but productivity decreased sharply after September due to stem lignification caused by excessive light during the summer. Conversely, the lower two layers exhibited faster growth rate of young shoots until the late cultivation period, but the quality decreased due to stem softening and leaf epinasty. To address the excessive light problem on the third floor during the summer, shading was implemented at 30% opacity in July and August, resulting in a 210% increase in rosemary young shoots count and a 162% increase in fresh weight per unit area compared to the unshaded control. To improve the lighting deficiency on the lower layer, supplemental lighting with LED at 30 W increased rosemary young shoot harvest by 168% from June to September compared to no supplemental lighting, but it decreased productivity after September. Therefore, when growing rosemary in multi-layer, it is judged that intensive production of young shoots is possible if the third floor (top layer) is shaded with 30% of light from July to August to prevent stem lignification, and the lower layer is temporarily supplemented with LED 30 W from June to September to increase young shoot growth.