• Journal of Bio-Environment Control
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• v.30 no.3
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• pp.237-243
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• 2021

The objective of this study was to evaluate the effect of stem number on plant growth, fruit quality, and yield of sweet peppers grown in greenhouses under supplemental lighting in winter. The seedlings were transplanted at 3.2 plants·m^-2 on October 26, 2020, and started supplemental lighting with 32 high pressure sodium lamps for 16-hour photoperiod from December 1, 2020 to May 25, 2021. Stems were differently trained with 2 and 3 numbers after branching nodes were developed. In the final harvest, the plant height was significantly shorter in the 3 stem-plants than in the 2 stem-plants. The number of nodes per stem and the leaves per plant were increased in the 3 stem-plants than in the 2 stem-plants, while the leaf area was less affected. There were no significant differences in the dry mass of leaves, stems, and immature fruits between the 2 and 3 stem-plants. The fruit fresh weight and fruit dry weight in the 3 stem-plants were decreased by 17% and 12% at 156 days after transplanting (DAT), and by 17% and 15% at 198 DAT compared to those in the 2 stem-plants, respectively. The marketable fruit rates were 93.6% and 95.4% in the 2 and 3 stem-plants, respectively. The total fruit yield in the 3 stem-plants was increased by 30.2% as compared to that in the 2 stem-plants. We concluded that the 3-stem-training cultivation positively affected the total fruit yield by sustaining adaptive vegetative growth of the plants. This result will help producers make useful decisions for increasing productivity of sweet peppers in greenhouses.

• Korean journal of applied entomology
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• v.60 no.2
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• pp.255-262
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• 2021

The potato tuber moth, Phthorimaea operculella (Zeller) has been known as a quarantine pest of potato. This study investigated inhibition doses of electron beam irradiation (EBM) by comparing their effects on the development and reproduction and DNA damage of the insect pest. Eggs (0-12 h old), larvae (3^rd and 5^th instar), pupae (less than 1 d old after pupation) and adults (less than 1 d old after emergence) were irradiated with increasing doses of EBM. The EBM with 150 Gy could not completely prevent the hatchability of eggs and pupation of the hatched larvae. The hatchability from the irradiated eggs were 19.3%. However, adult emergence from the irradiated eggs were completely inhibited. When 3^rd and 5^th instar larvae were irradiated at 100 Gy, the adult emergence from the irradiated larvae and the fecundity of the adults were completely inhibited. When pupae and adults were irradiated at 300 Gy and 400 Gy, respectively, the hatchability of the F₁ eggs was completely inhibited. The alkaline comet assay on the level of DNA damage by EBM in P. operculella adults indicates that the EBM increased DNA damage level in a dose-dependent manner, and the damage was repaired in a time-dependent manner. These results may recommend EBM of 150 Gy as a phytosanitary treatment for P. operculella. However further confirmative study is required for the practical application of this EBM dose for P. operculella disinfestation.

• Journal of Marine Life Science
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• v.5 no.1
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• pp.9-16
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• 2020

We evaluated the toxic effects of antifouling paint (irgarol and diuron) on the population growth rate (r) of the marine diatom, Skeletonema costatum. The r of S. costatum was determined after 96 hrs of exposure to irgarol (0, 0.31, 0.63, 1.25, 2.5 and 5 ㎍ l^-1) and diuron (0, 7.81, 15.63, 31.25, 62.5 and 125 ㎍ l^-1). It was observed that r in the control (absence of irgarol and diuron) were greater than 0.04, while r in the treatment groups decreased with increasing irgarol and diuron concentrations. Irgarol and diuron reduced r in a dose-dependent manner with significant decreases occurring at concentrations above 0.63 and 15.63 ㎍ l^-1, respectively. The EC₅₀ values of r in irgarol and diuron exposure were 1.09 and 45.45 ㎍ l^-1. No observed effect concentration (NOEC) were 0.31 and 7.81 ㎍ l^-1, the lowest observed effect concentration (LOEC) were 0.63 and 15.63 ㎍ l^-1. This result indicate that a concentration of greater than 0.63 ㎍ l^-1 of irgarol and 15.63 ㎍ l^-1 of diuron in marine ecosystems induced to decreasing r of S. costatum. Also, these toxic values can be useful as a baseline data for the toxic evaluation of irgarol and diuron in marine ecosystems.

• Journal of the Korean earth science society
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• v.42 no.3
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• pp.247-263
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• 2021

Climate change has been accelerating in coastal waters recently; therefore, the importance of coastal environmental monitoring is also increasing. Chlorophyll-a concentration, an important marine variable, in the surface layer of the global ocean has been retrieved for decades through various ocean color satellites and utilized in various research fields. However, the commonly used chlorophyll-a concentration algorithm is only suitable for application in clear water and cannot be applied to turbid waters because significant errors are caused by differences in their distinct components and optical properties. In addition, designing a standard algorithm for coastal waters is difficult because of differences in various optical characteristics depending on the coastal area. To overcome this problem, various algorithms have been developed and used considering the components and the variations in the optical properties of coastal waters with high turbidity. Chlorophyll-a concentration retrieval algorithms can be categorized into empirical algorithms, semi-analytic algorithms, and machine learning algorithms. These algorithms mainly use the blue-green band ratio based on the reflective spectrum of sea water as the basic form. In constrast, algorithms developed for turbid water utilizes the green-red band ratio, the red-near-infrared band ratio, and the inherent optical properties to compensate for the effect of dissolved organisms and suspended sediments in coastal area. Reliable retrieval of satellite chlorophyll-a concentration from turbid waters is essential for monitoring the coastal environment and understanding changes in the marine ecosystem. Therefore, this study summarizes the pre-existing algorithms that have been utilized for monitoring turbid Case 2 water and presents the problems associated with the mornitoring and study of seas around the Korean Peninsula. We also summarize the prospective for future ocean color satellites, which can yield more accurate and diverse results regarding the ecological environment with the development of multi-spectral and hyperspectral sensors.

• Journal of Korea Port Economic Association
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• v.37 no.1
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• pp.31-70
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• 2021

The purpose of this paper is to measure the clustering change and analyze empirical results, and choose the clustering ports for Busan, Incheon, and Gwangyang ports by using Hierarchical clustering(single, complete, average, and centroid), Silhouette, and 2SCE[the Second Stage(Type II) cross-efficiency] matrix clustering models on Asian container ports over the period 2009-2018. The models have chosen number of cranes, depth, birth length, and total area as inputs and container TEU as output. The main empirical results are as follows. First, ranking order according to the efficiency increasing ratio during the 10 years analysis shows Silhouette(0.4052 up), Hierarchical clustering(0.3097 up), and 2SCE(0.1057 up). Second, according to empirical verification of the Silhouette and 2SCE models, 3 Korean ports should be clustered with ports like Busan Port[ Dubai, Hong Kong, and Tanjung Priok], and Incheon Port and Gwangyang Port are required to cluster with most ports. Third, in terms of the ASEAN, it would be good to cluster like Busan (Singapore), Incheon Port (Tanjung Priok, Tanjung Perak, Manila, Tanjung Pelpas, Leam Chanbang, and Bangkok), and Gwangyang Port(Tanjung Priok, Tanjung Perak, Port Kang, Tanjung Pelpas, Leam Chanbang, and Bangkok). Third, Wilcoxon's signed-ranks test of models shows that all P values are significant at an average level of 0.852. It means that the average efficiency figures and ranking orders of the models are matched each other. The policy implication is that port policy makers and port operation managers should select benchmarking ports by introducing the models used in this study into the clustering of ports, compare and analyze the port development and operation plans of their ports, and introduce and implement the parts which required benchmarking quickly.

• Journal of Life Science
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• v.31 no.7
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• pp.617-625
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• 2021

To enhance the applications of apple pomace, which is a by-product of apple, this study analyzed the nutritional components, ursolic acid content, and antioxidant activity of different solvent (distilled water, fermented alcohol, and methanol) extracts. The samples included hot air-dried and freeze-dried apple pomace. The moisture, protein, fat, ash, and total dietary fiber contents of hot air-dried apple pomace were 3.2%, 3.9%, 2.4%, 2.0%, and 28.5%, respectively, and those of freeze-dried apple pomace were 8.2%, 3.4%, 2.4%, 1.8%, and 33.0%, respectively. Ursolic acid was not detected in the distilled water extract of either sample. However, in hot air-dried apple pomace, the methanol extract was 1,753.32 ㎍/ml, and the fermented alcohol extract was 1,532.94 ㎍/ml. In freeze-dried apple pomace, the methanol extract was 1,407.04 ㎍/ml, and the fermented alcohol extract was 1,221.81 ㎍/ml. The total polyphenol and flavonoid contents were 306.7 ㎍/ml and 950.1 ㎍/ml, respectively in methanol extracts of hot air-dried apple pomace and 277.6 ㎍/ml and 925.0 ㎍/ml, respectively in methanol extracts of freeze-dried apple pomace. 2, 2'-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activities of hot air-dried apple pomace were 73.3% in methanol extract and 59.4% in fermented alcohol extract, and those of freeze-dried apple pomace were 76.1% in methanol extract and 66.0% in fermented alcohol extract. Both samples had the lowest antioxidant activity in distilled water extracts. Similar to DPPH radical scavenging activity, both samples showed increasing 2,2'-azino-bis(3-ethylbenzothiazoline-6- sulfonic acid) (ABTS) radical scavenging activity in the order of methanol, fermented alcohol, and distilled water. All samples had stronger reducing power than ascorbic acid (311.5 ㎍/ ml) as a positive control.

• Korean Journal of Mineralogy and Petrology
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• v.34 no.2
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• pp.133-146
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• 2021

Aragonite is one of common polymorphs of calcium carbonate (CaCO₃) and formed via biological or physical processes through precipitation in many different environments including marine ecosystems. It is noted that aragonite formation and growth as well as the substitution of trace elements such as strontium (Sr) in the aragonite structure would be dependant on several key parameters such as concentrations of chemical species and temperature. In this study, properties of the incorporation of Sr into aragonite were investigated over a wide range of various saturation conditions and temperatures similar to the marine ecosystem. All pure aragonite samples were inorganically synthesized through a constant-addition method with varying concentrations of the reactive species ([Ca]=[CO₃] 0.01-1 M), injection rates of the reaction solution (0.085-17 mL/min), and solution temperatures (5-40 ℃). Pure aragonite was also formed even under the Sr incorporation conditions (0.02-0.5 M, 15-40 ℃). When temperature and saturation index (SI) with respect to aragonite increased, the crystallinity and the crystal size of aragonite increased indicating the growth of aragonite crystal. However, it was difficult to interpret the crystal growth rate because the crystal growth rate calculated using BET-specific surface area was significantly influenced by the crystal morphology. The distribution coefficient of Sr (K_Sr) into aragonite decreased from 2.37 to 1.57 with increasing concentrations of species (Ca²⁺ and CO₃^2-) at a range of 0.02-0.5 M. Similarly, it was also found that K_Sr decreased 1.90 to 1.54 at a range of 15-40 ℃. All K_Sr values are greater than 1, and the inverse correlation between the K_Sr and the crystal growth rate indicate that Sr incorporation into aragonite is in a compatible relationship.

• 한국노년학
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• v.38 no.3
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• pp.705-723
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• 2018

In this study we review the selected articles on elderly health and medical care published in the Journal of the Korea Gerontological Society (JKGS) in the last 40 years, and make suggestions for future research directions for gerontological health and medical care issues. Of all the 40 year publications from volume 1 (1980) to 38 (2017), we first examined the 30th anniversary review on the subject of gerontological nursing care and healthcare policies published in JKGS from 1980 (vol. 1, No. 1) to 2008 (vol. 28, No. 2), and reviewed recent 237 researches of this decade (out of all 655 articles from 2008, vol. 28, No. 3 to 2017, vol. 38, No. 4). We could find the following trends. Firstly, the analysis of the primary authors in the past 10 years revealed that those in public health, nursing and other health-related including physical education areas have dealt the subjects focusing on physical health while those in social welfare mostly on mental health. That is, physical health has been the prime subject of researches in the health and medical care area. Secondly, in the same period quantitative researches were accounted for 89.9%, which is similar to the trend of the first 30 years 81.5 %. On the other hand, qualitative studies were only 11 cases and the focus group interview were the most frequently used method comprising 33.3% among them. Thirdly, the non-experimental researches in the past 10 years comprise 65.4%, which was 82.7% in 1980 2008 period, indicating the increasing trend in experimental researches to deal with the issues in medical and healthcare fields. Lastly, the subjects of the researches were mostly the elders who are healthy, residents of city areas, or home dwellers, and 60% of them were over 65 years old in the past 10 years while the proportion was 42.7% in the previous review period. 81.6 % of the researches in the past 10 years was dealing both genders, slightly decreased trend compared to 88.5% of the previous review period. This study reveals that the researches in non-experimental physical health remains the main stream of JKGS despite the efforts by some researchers to diversify the methods and subjects. Systematic and in-depth researches employing multidisciplinary, qualitative, longitudinal and meta-analytical approaches are called for to guide the gerontolgical health issues with preventive and proactive perspectives.

• Cross-Cultural Studies
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• v.51
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• pp.291-327
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• 2018

'Hyesung' and 'Jeilsun' are media that reveal the new searches of the Gaebyeoksa Publishing Company of the 1930s. However, studies in the past did not sufficiently analyze their significance. Furthermore, there are no analyses on how the critical minds of 'Hyesung' and 'Jeilsun' were linked to 'Gaebyeok', which continued publications in 1934. The 1930s when 'Hyesung' and 'Jeilsun' were published, was a time where the media of colonial Chosun was rapidly changing, and it was a time where literary magazines were increasing in quantity. In the 1930s, Gaebyeoksa attempted to actively respond to such changes reflected in the media. This was demonstrated through the publication of the new media 'Hyesung' and 'Jeilsun' and continuing publication of the 'Gaebyeok' magazine in 1935. This study analyzed the literary discourses shown in the magazines published by Gaebyeoksa in the 1930s based on 'Hyesung', 'Jeilsun', and the continued publication of 'Gaebyeok'. Through such analysis, this study examined how the magazines published by Gaebyeoksa perceived the culture and literature of colonial Chosun in the 1930s and in which direction it tried to reorganize this.

• Food Engineering Progress
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• v.14 no.3
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• pp.208-216
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• 2010

Lab scale experiments were conducted in order to assess the applicability of $CaCO_{3}$-alginate beads as neutralizer for the high cell density cultivation and prepare the direct vat inoculation cultures of isolated sourdough lactic acid bacteria. With increasing the amount of bead and decreasing the diameter of bead in acidic solution, the neutralizing effect of $CaCO_{3}$-alginate bead became higher. In batch process with $CaCO_{3}$-alginate beads, Lactobacillus amylovorus DU-21 isolated from sourdough showed the highest viable cell counts and optical density in MRS broth. The values of viable cell counts and optical density were 9.996 log CFU/mL and 3.97, respectively. Experiments on the conditions which increase viability during lyophilization were carried out and the following results were obtained; 15% glycerol revealed the high cryoprotective effect on the concentrated cultures during lyophilization among the two cryoprotective agents. Consequently, $CaCO_{3}$-alginate beads and 15% glycerol were found to be useful not only to cultivate Lactobacillus amylovorus DU-21 but also to preserve strain.