• Phonetics and Speech Sciences
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• v.16 no.2
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• pp.49-58
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• 2024

This study aimed to compare the acoustic measurements of speech samples recorded from individuals with normal voices using various devices: the Computerized Speech Lab (CSL), a unidirectional wired pin-microphone (WIRED) suitable for smartphones, the built-in omnidirectional microphone (SMART) of smartphones, and Bluetooth-connected wireless earphones, specifically the Galaxy Buds2 Pro (WIRELESS). This study included 40 normal adults (12 males and 28 females) who had not visited an otolaryngologist for respiratory diseases within the past three months. Participants performed sustained vowel /a/ phonation for four seconds and reading tasks with sentences ("Walk") and paragraphs ("Autumn") in a sound-treated booth. Recordings were simultaneously conducted using the four different devices and synchronized based on the CSL-recorded samples for analysis using the MDVP, ADSV, and VOXplot programs. Compared with CSL, the Cepstral Spectral Index of Dysphonia (CSID_V, CSID_S) and Acoustic Voice Quality Index (AVQI) values were lower in the WIRED and higher in the SMART. The opposite trend was observed for the L/H spectral ratios (SR_V and SR_S), and the WIRELESS demonstrated task-specific discrepancies. Furthermore, both the fundamental frequency (F0) and the cepstral peak prominence of the vowel samples (CPP_V) had intraclass correlation coefficient (ICC) values above 0.9, indicating high reliability. These variables, F0 and CPP_V were considered highly reliable for voice recordings across different microphone types. However, caution should be exercised when analyzing and interpreting variables such as the SR, CSID, and AVQI, which may be influenced by the type of microphone used.

• Journal of Food Hygiene and Safety
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• v.39 no.3
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• pp.221-230
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• 2024

Pesticide residues were monitored in dried red pepper and pepper powder samples purchased in Northern Gyeonggi-do and from domestic online markets. The QuEChERS method was used to prepare 88 samples. GC-MS/MS and LC-MS/MS were used to analyze 338 pesticide residues. In the study, pesticide residues were detected in 70 samples (79.5%), with residues exceeding the maximum residue limits (MRL) in 4 samples (4.5%). Pesticide levels exceeded the MRL in imported samples, with two samples of dried red pepper and two samples of pepper powder showing elevated levels. Among the 61 pesticides detected, tebuconazole, a fungicide was most frequently detected (52 times). Tricyclazole, which is used to control the main disease affecting rice, exceeding the MRL in 3 of 12 Vietnam-origin samples. Ethion exceeded the MRL in one Indian-origin sample. Both tricyclazole and ethion are banned for use in pepper products in Korea and are regulated under the positive list system (PLS). Conversely, pesticides detected in domestic samples were within the MRLs. Therefore, authorities should monitor pesticide residues in imported red pepper products.

• Food Science and Preservation
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• v.31 no.3
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• pp.423-432
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• 2024

In this study, a vacuum tumbler with 4 impellers (DVT) was designed and applied for thawing frozen pork (vacuum -60 kPa, jacket 35℃, 1 rpm). Quality characteristics of the thawed pork were compared with those of industrially thawed meat by natural air at room temperature (NAT) and imported vacuum tumbler (IVT). The thawing time for frozen pork (303.36 kg) using DVT (165 min) was much shorter than that of NAT (4,200 min). DVT-thawed pork had lower drip loss (0.85%) than NAT (2.08%). DVT-thawed pork showed a pH of 5.92, a total bacterial count of 1.96±0.02 log CFU/g and no coliforms. Deteriorations in fat (TBARS 0.31±0.01 MDA mg/kg) and protein (VBN 5.67±1.98 mg%) in DVT-thawed pork were significantly lower than those of NAT (p<0.05). DVT-thawed pork had a high water-holding capacity (WHC, 97.5%). The hardness (34.59±0.46 N) and chewiness (188.21±0.17) of cooked DVT-thawed pork were about 5-6 times lower than those of NTA. Microstructure (SEM) showed myofibrillar damage in NAT-thawed pork, whereas dense myofibrillar structure was observed in DVT-thawed pork. DVT was better or similar to IVT in all evaluation parameters. The designed DVT is expected to be used as an efficient thawing method in terms of processing time and yield and to produce thawed meat with high WHC, soft texture, and low spoilage by minimizing tissue damage.

• Food Science and Preservation
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• v.31 no.3
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• pp.486-498
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• 2024

This study examined the effects of a soybean sprouts mixture containing 1.5% Hovenia dulcis Thunb. fruit concentrate (SHM) on relieving hangovers and improving liver function in chronically alcohol-treated rats. The ampelopsin and L-asparagine contents in the SHM were 10.52, 35.19 ppm. When chronic alcohol-induced rats were treated with SHM, the body weight increased and the liver weight decreased. The serum alcohol and acetaldehyde concentrations were lowest in the SHM group, and the hepatic ADH and ALDH activities were highest in the SHM group. Chronic alcohol induction increased the activity of liver function indicator enzymes such as ALT, AST, and GGT, but the activity was decreased significantly with the SHM treatment. The triglyceride content in hepatic and serum blood samples was lowest in the SHM group. The serum total cholesterol and LDL cholesterol contents decreased in the SHM group, and the HDL cholesterol content increased. The color of the hepatic observed morphologically in the SHM group was reddish brown, and the size and number of lipid droplets in the hepatic observed pathologically decreased. The hepatic and serum lipid peroxidation content of the SHM group decreased. The hepatic and serum GSH content increased in the SHM group. Therefore, SHM can be a functional food that can help hangovers and improve liver function.

• Journal of Korean Elementary Science Education
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• v.43 no.3
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• pp.415-432
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• 2024

This study developed and applied the teacher education model and its principles for science classes using Virtual and Augmented Reality (VR/AR) content and analyzed preservice elementary teachers' feedback on the teacher education model and the changes in their perceptions as to the use of VR/AR content. First, existing Technological Pedagogical Content Knowledge (TPACK) teacher education models and prior studies on the use of the VR/AR contents were reviewed to derive the teacher education model to cultivate the VR/AR-TPACK and set the key principles for each of its stages. The developed teacher education model has five stages: exploration, mapping, collaborative design, practice, and reflection. Second, to examine the appropriateness of the model's five stages and principles, we applied it within the regular course of instruction at the university of education, which was attended by 25 preservice elementary teachers. This study collected data from surveys on the perception of the usage of VR/AR contents before and after the course, as well as the group lesson plans prepared by the preservice teachers, and their feedback on the teacher education model. The feedback on the teacher education model and the survey conducted by the preservice teachers before and after the course were analyzed through open coding and categorization. As a result, most preservice teachers expressed positive opinions about the activities and experiences at each stage of the implementation of the teacher education model. Perceptions related to the usage of the VR/AR content changed in three aspects: first, the vague positive perception of the VR/AR content has changed to a positive perception based on specific educational affordance. Second, they recognized the need for preparedness by anticipating potential problems associated with the use of the VR/AR content. Third, they came to view the VR/AR contents as a useful instructional resource that the teachers could use. Based on these results, we discussed the implications for the VR/AR-TPACK teacher education model and assessed the limitations of the research.

• Journal of Korea Water Resources Association
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• v.57 no.7
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• pp.437-449
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• 2024

Rainfall-runoff prediction studies using deep learning while considering catchment attributes have been gaining attention. In this study, we selected two models: the Transformer model, which is suitable for large-scale data training through the self-attention mechanism, and the LSTM-based multi-state-vector sequence-to-sequence (LSTM-MSV-S2S) model with an encoder-decoder structure. These models were constructed to incorporate catchment attributes and predict the inflow of 10 multi-purpose dam watersheds in South Korea. The experimental design consisted of three training methods: Single-basin Training (ST), Pretraining (PT), and Pretraining-Finetuning (PT-FT). The input data for the models included 10 selected watershed attributes along with meteorological data. The inflow prediction performance was compared based on the training methods. The results showed that the Transformer model outperformed the LSTM-MSV-S2S model when using the PT and PT-FT methods, with the PT-FT method yielding the highest performance. The LSTM-MSV-S2S model showed better performance than the Transformer when using the ST method; however, it showed lower performance when using the PT and PT-FT methods. Additionally, the embedding layer activation vectors and raw catchment attributes were used to cluster watersheds and analyze whether the models learned the similarities between them. The Transformer model demonstrated improved performance among watersheds with similar activation vectors, proving that utilizing information from other pre-trained watersheds enhances the prediction performance. This study compared the suitable models and training methods for each multi-purpose dam and highlighted the necessity of constructing deep learning models using PT and PT-FT methods for domestic watersheds. Furthermore, the results confirmed that the Transformer model outperforms the LSTM-MSV-S2S model when applying PT and PT-FT methods.

• Journal of the Korea Organic Resources Recycling Association
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• v.17 no.3
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• pp.27-39
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• 2009

The main objective of this study is to investigate the characteristics of combustion by analyzing fuel gases from a combustion equipment with various combustion conditions for refuse-derived fuels (RDFs). CO gas is a parameter for indicating of incomplete combustion during a combustion process. The lowest CO gas was produced when the experiment conditions were m=2 under air-fuel condition and $800^{\circ}C$. $CO_2$ gas is a final product after complete combustions. The highest amount of $CO_2$ gas was produced when the experiment conditions were m=2 under air-fuel condition and $800^{\circ}C$. The highest level of $SO_2$ gas was produced in S.1 sample containing the highest sulfur. The highest level of NOx gas was produced in S.1 sample with the highest nitrogen content and air-fuel condition of m=2 under temperature of $800^{\circ}C$. HCl gas that is generated by reacting with metals catalyst through oxygen catalyst reaction during combustion process is a precursor of dioxin formation. The higher level of HCl gas was produced in the sample with higher chlorine content. The lowest level of HCl gas was produced when the experiment conditions were air-fuel condition of m=2 and $800^{\circ}C$. The lowest level of $NH_3$ gas was generated when the experiment condition was m=2 under air-fuel condition and after 3 minutes. Air-fuel condition is more important to create $NH_3$ gas than operating temperatures. Higher level of $H_2S$ gas was generated in S.1 sample with the higher sulfur content and was created in RDFs that contain higher mixture ratios of sewage sludge and food wastes. A result of combustion, gases and gases levels from the combustion of S.1 and S.2 were very similar to the combustion of a stone coal. As results of this research, when evaluating the feasibility of the RDFs, the RDFs could be used as auxiliary and main fuels.

• The Journal of the Convergence on Culture Technology
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• v.10 no.4
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• pp.175-181
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• 2024

The U.N. Security Council's North Korea Sanctions Committee estimated that the amount of North Korea's cyberattacks on virtual asset-related companies from 2017 to 2023 was about 4 trillion won. North Korea's cyberattacks have secured funds through cryptocurrency hacking as it has been restricted from securing foreign currency due to economic sanctions by the international community, and it also shows the form of technology theft against defense companies, and illegal assets are being used to maintain the Kim Jong-un regime and develop nuclear and missile development. When North Korea conducted its sixth nuclear test on September 3, 2017, and declared the completion of its national nuclear armament following the launch of an intercontinental ballistic missile on November 29 of the same year, the U.N. imposed sanctions on North Korea, which are considered the strongest economic sanctions in history. In these difficult economic situations, North Korea tried to overcome the crisis through cyberattacks, but as a result of analyzing the changes through the North's cyber attack cases, the strategic goal from the first period from 2009 to 2016 was to verify and show off North Korea's cyber capabilities through the neutralization of the national network and the takeover of information, and was seen as an intention to create social chaos in South Korea. When foreign currency earnings were limited due to sanctions against North Korea in 2016, the second stage seized virtual currency and secured funds to maintain the Kim Jong-un regime and advance nuclear and missile development. The third stage is a technology hacking of domestic and foreign defense companies, focusing on taking over key technologies to achieve the five strategic weapons tasks proposed by Chairman Kim Jong-un at the 8th Party Congress in 2021. At the national level, security measures for private companies as well as state agencies should be established against North Korea's cyberattacks, and measures for legal systems, technical problems, and budgets related to science are urgently needed. It is also necessary to establish a system and manpower to respond to the ever-developing cyberattacks by focusing on cultivating and securing professional manpower such as white hackers.

• Journal of the Daesoon Academy of Sciences
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• v.49
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• pp.187-227
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• 2024

The purpose of this article is to examine the prospects of the religious cultural experience program of Daesoon Jinrihoe by referring to the current status of Korea's Buddhist temple stays, which began with the 2002 World Cup and have become a regular program for the general public with the establishment of the Cultural Corps of Korean Buddhism in 2004. The motivation for Korean participation is mainly rest, while foreigners tend to be more interested in Korean traditional culture. During the experience, the perceived value felt by the participants led to satisfaction and an intention to revisit. Temple stays have contributed to the globalization of Korean Buddhism. The temple stay of Daesoon Jinrihoe is a religious cultural experience program for the public. If it became a regular program, the target could be expanded to include foreigners who wish to experience Korean culture. The activities such as wearing Hanbok, taking a Dojang Tour, praying, and dialogue over tea can be allocated to the program. As a result, the perceived value by participants could be taken as a cognitive value. For instance, they could learn about Sangje's Reordering of the Universe that transformed the order of Sanggeuk (Mutual Contention) into the order of Sangsaeng (Mutual Beneficence). They way that they live their lives could change as a result of these new understandings. The emotional value of the experience would come from experiencing traditional Korean religious culture. The prospect of implementing such a program is twofold: firstly, there are the tasks of proper preparation, and secondly, there are the positive effects. The tasks would first involve creating a systematic and organized center point. Next there would be the matter of preparing spaces for the temple stay, and lastly, an online platform for advertisement, recruitment, and application would also be greatly beneficial. This is a vision that could contribute to the improving public image of the order, its globalization, and to the overall improvement of the facilities and management that would produce a more socially friendly environment.

• Journal of Life Science
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• v.34 no.8
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• pp.567-575
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• 2024

New breeding techniques (NBT) recognize specific DNA sequences and remove, modify, or insert DNA at a desired location, and can be used to treat genetic diseases in humans or to improve the traits of livestock or crops. In this study, we conducted a comparative analysis of various agricultural traits and assessed the safety of gene transferability in third-generation genome-editing rice (OsCKq1-G₃) with T and G nucleotide insertions developed using the CRISPR/Cas9 SDN-1 method, in comparison to its parental line (Oryza sativa L., cv Ilmi). The analyzed traits included heading date, culm length, panicle length, tiller number, yield, germination rate, viviparous germination rate, shattering, after wintering seed viability, the presence of toxins and allergens. The target trait, heading date, exhibited a high significant difference of approximately 5 days. Culm length, panicle length, tiller number, yield showed no significant differences compared to the parental line. No T-DNA bands indicating gene transfer were detected. In the third generation of genome-edited rice, the T-DNA was confirmed to be eliminated as successive generations advanced through self-pollination. Through the analysis of germination rate, viviparous germination rate, shattering, and after wintering viability, we confirmed that the genome-editing rice has no potential for weediness. The ORF and amino acid sequences of the genome-editing rice did not reveal any toxins and allergens. The results of this study can be utilized as important data for the environmental risk assessment of genome-editing rice.