• Korean Journal of Remote Sensing
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• v.39 no.5_1
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• pp.695-713
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• 2023

In coastal waters, phytoplankton,suspended particulate matter, and dissolved organic matter intricately and nonlinearly alter the reflectivity of seawater. Neural network technology, which has been rapidly advancing recently, offers the advantage of effectively representing complex nonlinear relationships. In previous studies, a three-stage neural network was constructed to extract the inherent optical properties of each component. However, this study proposes an algorithm that directly employs a deep neural network. The dataset used in this study consists of synthetic data provided by the International Ocean Color Coordination Group, with the input data comprising above-surface remote-sensing reflectance at nine different wavelengths. We derived inherent optical properties using this dataset based on a deep neural network. To evaluate performance, we compared it with a quasi-analytical algorithm and analyzed the impact of log transformation on the performance of the deep neural network algorithm in relation to data distribution. As a result, we found that the deep neural network algorithm accurately estimated the inherent optical properties except for the absorption coefficient of suspended particulate matter (R² greater than or equal to 0.9) and successfully separated the sum of the absorption coefficient of suspended particulate matter and dissolved organic matter into the absorption coefficient of suspended particulate matter and dissolved organic matter, respectively. We also observed that the algorithm, when directly applied without log transformation of the data, showed little difference in performance. To effectively apply the findings of this study to ocean color data processing, further research is needed to perform learning using field data and additional datasets from various marine regions, compare and analyze empirical and semi-analytical methods, and appropriately assess the strengths and weaknesses of each algorithm.

• Korean Journal of Remote Sensing
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• v.39 no.5_1
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• pp.669-681
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• 2023

Studies have tried to apply remote sensing technology, a non-destructive survey method, instead of the existing destructive survey, which requires relatively large labor input and a long time to estimate chlorophyll content, which is an important indicator for evaluating the growth of fruit trees. This study was conducted to non-destructively evaluate the chlorophyll content of pear tree leaves using unmanned aerial vehicle-based hyperspectral imagery for two years(2021, 2022). The reflectance of the single bands of the pear tree canopy extracted through image processing was band rationed to minimize unstable radiation effects depending on time changes. The estimation (calibration and validation) models were developed using machine learning algorithms of elastic-net, k-nearest neighbors(KNN), and support vector machine with band ratios as input variables. By comparing the performance of estimation models based on full band ratios, key band ratios that are advantageous for reducing computational costs and improving reproducibility were selected. As a result, for all machine learning models, when calibration of coefficient of determination (R²)≥0.67, root mean squared error (RMSE)≤1.22 ㎍/cm², relative error (RE)≤17.9% and validation of R²≥0.56, RMSE≤1.41 ㎍/cm², RE≤20.7% using full band ratios were compared, four key band ratios were selected. There was relatively no significant difference in validation performance between machine learning models. Therefore, the KNN model with the highest calibration performance was used as the standard, and its key band ratios were 710/714, 718/722, 754/758, and 758/762 nm. The performance of calibration showed R²=0.80, RMSE=0.94 ㎍/cm², RE=13.9%, and validation showed R²=0.57, RMSE=1.40 ㎍/cm², RE=20.5%. Although the performance results based on validation were not sufficient to estimate the chlorophyll content of pear tree leaves, it is meaningful that key band ratios were selected as a standard for future research. To improve estimation performance, it is necessary to continuously secure additional datasets and improve the estimation model by reproducing it in actual orchards. In future research, it is necessary to continuously secure additional datasets to improve estimation performance, verify the reliability of the selected key band ratios, and upgrade the estimation model to be reproducible in actual orchards.

• Korean Journal of Poultry Science
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• v.50 no.3
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• pp.133-141
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• 2023

We conducted a 5 × 5 diallel cross-combination test using 1,060 chickens from pure lines of Korean Rhode-C, -D, Korean Leghorn-F, -K, and Korean Native Yellowish-brown chicken (KNC-Y) to develop a new Korean native chicken layer breeder. The laying performance and combining ability, including livability, body weight, age of first egg-laying, hen-day egg production, and egg weight, were analyzed. The livability from birth to 48 weeks was 72.1±24.0%, with the highest observed in the YC and the lowest in the DK combination (P<0.01). The YC combination exhibited the highest general combining ability (GCA), while the YD combination showed the highest specific combining ability (SCA). Regarding body weight, combinations involving Leghorn showed lighter weights compared to combinations with Rhode and KNC-Y (P<0.01). Additionally, the offspring from the KNC-Y combination reached sexual maturity earlier than those from the Rhode combination. The hen-day egg production was 70.7±12.0%, with the highest seen in the CK combination at 86% (P<0.01). The effects of GCA and SCA on hen-day egg production were similar, with the SCA being highest in the YD combination and the GCA being highest in the Rhode-C. Significant differences in egg weight were observed among the combinations, with the eggs from Rhode and Leghorn combinations being heavier than those from combinations with KNC-Y (P<0.01). In conclusion, the YC and YD combinations, characterized by excellent livability, are highly desirable paternal strains, while the CF and CK combinations, with excellent laying performance and moderate egg weight, are preferred maternal strains for Korean native chicken layer breeders.

• Journal of Life Science
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• v.33 no.11
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• pp.897-904
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• 2023

This study was done to develope genetic markers with the unique characteristics of genes according to the genomic information of Bacillus velezensis K10. B. velezensis K10 maintained a total of 4,159,835 bps, which was found to encode 5,136 open reading frames (orfs). B. velezensis K10 was found to have much more gene migration due to external factors overall compared to standard strain B. velezensis JS25R. In order to discover genetic selection markers, orfs on the genome to be easily induced to gene mutation were surveyed such as recombinase, integrase, transposase, and phage-related genes. As a result of the investigation, 9 candidate markers were isolated with high possibility as genetic selection markers. Although a part in the various origin's areas showed specificities in comparison with homology, the selected markers were all existed in phage-related areas because they were relatively lower homologies in phage-related genes. PCR analysis was done on B. licheniformis K12, B. velezensis K10, B. subtilis, and B. cereus to establish them as inter-species candidate selection markers. As a result, it was confirmed that B. velezensis K10-specific PCR products were formed in a total of 6 primer sets such as BV3 and BV5 to 9. On the other hand, analysis at the subspecies level observed the formation of B. velezensis K10-specific PCR products in 4 primer sets such as BV3, 5, 8, and 9. Among them, since BV5 and BV8 were detected by very specific results, we suggest that BV5 and 8 can be used as B. velezensis K10 gene selection markers at the species and sub-species level.

• Korea Trade Review
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• v.48 no.3
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• pp.131-150
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• 2023

The purpose of this study was to find a countermeasure to the U.S. import refusals for the Korean healthcare and life sciences industry. To this end, an analysis of trends during the pandemic was conducted using the KITA Border Rejection Database, which includes information on items and types of import refusals. The reason for rejection was also analyzed according to the FDA violation codes. The degree of countermeasure for import refusals was identified by measuring the unit rejection rate (URR). The results of the analysis showed that the major U.S. import refusals for the Korean healthcare and life sciences industry had expanded from contact lenses to COVID-19 diagnostic kits and drugs after the pandemic broke out. The major reasons for import refusals were non-compliance with the Predicate Device and Drugs Act and non-approval by the FDA for products and facilities. On the other hand, the unit rejection rate (URR) of major items in the Korean healthcare and life sciences industry was measured higher than the industry average. The results therefore showed a low level of response to U.S. import refusals. The results of the analysis of reasons for import refusals by item according to FDA violation codes were as follows. First of all, the main violation for contact lenses and COVID-19 diagnostic kits corresponded to misbranding. This was often due to the fact that Korean companies did not provide the relevant notices and information required by the FDA. Many cases also failed to demonstrate a substantial equivalency compared to predicate devices already on the market. On the other hand, applications for new unapproved drugs were not accepted as they had yet to pass relevant regulations that would prove their safety and efficacy. In conclusion, import refusals for the Korean healthcare and life sciences industry were found to be closely related to technical barriers to trade (TBT).

• Journal of Marine Life Science
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• v.8 no.2
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• pp.166-177
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• 2023

The giant freshwater prawn (Macrobrachium rosenbergii) suffers economic losses in aquaculture facilities due to problems such as poor body color and carapace weakness. While this species is farmed on an animal-based diet, in the wild it consumes a detritus diet with a high proportion of plant matter. The plant matter they consume in the wild is not only a source of basic nutrients, but also carotenoids, which are responsible for body color. Korean goldenbell (Forsythia koreana) is a flowering tree widely distributed in Korea, and its leaves contain carotenoids comparable to yellow carrots. In this study, we investigated the effects of feeding Forsythia leaves to M. rosenbergii on their body color and health. The experimental diets were 100% commercial feed (control), CON, 80% commercial feed plus 20% Forsythia leaf powder, FP, and 80% commercial feed plus 20% unprocessed Forsythia leaves, FL, and each diet was fed to juvenile prawn with an average weight of 1.1 ± 0.2 g for 10 weeks. In terms of body color, the CON prawn were consistently clear ivory in color, while the FP and FL prawn changed from blue to dark brown as the days of rearing progressed. Survival and growth were not significantly different between CON and FP or FL. Histological comparison of the hepatopancreas revealed that the vacuole size of B cells, the constituent cells of the hepatopancreatic tubule, was significantly larger in FP and FL compared to CON. The vacuoles of B cells are responsible for the absorption and digestion of nutrients, suggesting that the supply of Forsythia leaves may have had a positive effect on the health of the M. rosenbergii. The above results show that the use of Forsythia leaves in the aquaculture of M. rosenbergii can be expected to improve body color and health without inhibiting growth.

• Journal of Marine Life Science
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• v.8 no.2
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• pp.136-149
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• 2023

Basic bioactivities (antioxidant, anti-inflammatory, antibacterial, anticancer, antiviral) were investigated from 370 strains of marine bacteria, fungi, and microalgae obtained from various marine environmental regions in Korea, and the activity results were obtained at the collection site, isolation source, and species level was compared. In the case of marine bacteria, strains belonging to the generally useful genera Streptomyces and Bacillus were observed to have particularly strong efficacy and useful resources were mainly isolated from marine sediments. In the case of marine fungi and microalgae, results showing strong species-specific activity were confirmed, and results showing efficacy-specific activity were also obtained. Based on these results, it is a research result that can facilitate priority access as a strategic material for industrial revitalization and the establishment of a strategy to secure resources based on usefulness when conducting research on chemicals that are selectively effective against specific diseases or when conducting resource-based research. In addition, we believe that by using these results as material for sale through the Marine BioBank (MBB), academia and industry can use them to help accelerate the revitalization of the marine bio industry.

• Analytical Science and Technology
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• v.36 no.6
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• pp.300-314
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• 2023

The quality of the products was investigated by analyzing fluorine content, pH, preservatives and tar colors in 31 dentifrice products (6 items for children) and 15 mouthwash products (2 items for children) marketed. It was intended to provide correct information to consumers by checking whether the standards and product indications match. As a result of measuring the fluoride concentration, 26 dentifrice and 15 mouthwash products contained from 48 to 1,472 ppm and from 85 to 225 ppm, respectively. Fluorine detection rates of dentifrice and mouthwash products were 83.9 and 83.3 %, respectively showing similar levels. Of the 41 fluoride-detected dentifrice and mouthwash products, 40 were 90.7~109.8 % of the displayed amount and suitable for the fluorine content standard of 90.0 to 110.0 %, but one dentifrice was found to be inappropriate at 36.3 % of the content indicated on the product. The pH of the dentifrice was 5.1~9.4, and the mouthwash was 4.2~6.2, which met all standards. As a result of simultaneous analysis of the concentration of six preservatives, benzoic acid was detected the most in 15 cases with a 30.6 % detection rate, sorbic acid was detected in 9 cases (detection rate of 18.4 %), and all four types of methyl p-hydroxybenzoate, ethyl p-hydroxybenzoate, propyl p-hydroxybenzoate, butyl p-hydroxybenzoate were not detected. As a result of analyzing the concentration of 10 types of tar colors, six types including red40, yellow4, yellow5, yellow203, green3, and blue1 were detected in a total of 9 cases (2 dentifrices and 7 mouthwashes) with blue1 being the most frequently detected. Detected fluorine concentration, added preservatives and tar colors were consistent with the product markings and it was well written on product packaging. The detected preservatives and tar colors were at a safe level due to low risk compared to Acceptable Daily Intake.

• Analytical Science and Technology
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• v.36 no.6
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• pp.291-299
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• 2023

The benzo[a]pyrene in edible oils is extracted using methods such as Liquid-liquid, soxhlet and ultrasound-assisted extraction. However these extraction methods have significant drawbacks, such as long extraction time and large amount of solvent usage. To overcome these drawbacks, this study attempted to improve the current complex benzo[a]pyrene analysis method by applying the QuEChERS (Quick, Easy, Cheap, Effective, Rugged and Safe) method that can be analyzed in a simple and short time. The QuEChERS method applied in this study includes extraction of benzo[a]pyrene into n-hexane saturated acetonitrile and n-hexane. After extraction and distribution using magnesium sulfate and sodium chloride, benzo[a]pyrene is analyzed by liquid chromatography with fluorescence detector (LC/FLR). As a result of method validation of the new method, the limit of detection (LOD) and quantification (LOQ) were 0.02 ㎍/kg and 0.05 ㎍/kg, respectively. The calibration curves were constructed using five levels (0.1~10 ㎍/kg) and coefficient (R²) was above 0.99. Mean recovery ratio was ranged from 74.5 to 79.3 % with a relative standard deviation (RSD) between 0.52 to 1.58 %. The accuracy and precision were 72.6~79.4 % and 0.14~7.20 %, respectively. All results satisfied the criteria ranges requested in the Food Safety Evaluation Department guidelines (2016) and AOAC official method of analysis (2023). Therefore, the analysis method presented in this study was a relatively simple pretreatment method compared to the existing analysis method, which reduced the analysis time and solvent use to 92 % and 96 %, respectively.

• Journal of Korean Society of Forest Science
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• v.112 no.4
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• pp.472-489
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• 2023

This study was conducted to derive the optimal estimation equations for deriving the green and dry weights of Larix kaempferi (Japanese larch) and Pinus rigida (Rigida pine), which are major coniferous tree species in South Korea. The equations were then used to develop weight tables. Table development began with the sampling of 150 L. kaempferi and 90 P. rigida trees distributed throughout the national scale, after which green weights were measured on-site. Samples from each stand were then collected, and their dry weights were measured in a laboratory. The equation used to calculate green and dry weights was divided into a one-variable formula that uses only the diameter at breast height (DBH) and a two-variable equation that employs DBH and height. The equations used to estimate the green and dry weights of logs were divided into one- and two-variable equations using DBH. Statistical data, such as the fitness index (FI), root mean square error, standard error of estimation, and residual diagram, were used to verify the suitability of the estimation equations. Applicability was examined by calculating weights using the derived optimal equations. The equation W = bD+cD² was used in measurements involving only DBH, whereas the equation W = aD^bH^c was employed in cases involving both diameter and height at breast height. The FI of W = bD+cD² was 0.91, while that of W = aD^bH^c was 0.95, both of which are high values. With these estimation formulas, weight tables for the green and dry weights of L. kaempferi and P. rigida were prepared and compared with weight tables created 20 years ago. The green and dry weight tables of both species were larger.