This study longitudinally examined how adolescents’ game use over time affects self-control, health status and health management, academic achievement, and family and peer relationships. To this end, we analyzed five-wave panel data from a national game user panel survey and sequentially applied latent growth models (LGMs), parallel-process LGMs, and time-varying covariate models. First, unconditional LGMs were estimated for eight variables—game use, self-control, health status, health management, academic achievement, parent–child communication, academic stress, and peer stress. The results showed that game use increased slightly but significantly over time, whereas self-control, health management behaviors, and academic achievement exhibited overall declining trajectories. Parent–child communication started at a relatively high level and showed no significant mean change, while academic and peer stress remained at relatively low levels with minimal mean-level fluctuation across waves. Because the mean of the linear slope factor was not significant for parent relationship, academic stress, or peer relationship, these variables were treated as comparatively stable contexts and excluded from subsequent models focusing on change dynamics. Next, we estimated conditional LGMs in which game use was included as a time-varying covariate in the growth models for self-control, health management, and academic achievement. Across all waves, higher game use was consistently associated with lower concurrent self-control, and with poorer health management and lower school grades at most time points. For health management, the negative association with game use was pronounced at the first three waves but its magnitude attenuated over time and became statistically nonsignificant at later waves. By contrast, academic achievement displayed a robust pattern of “increased game use → lower concurrent grades” at all five waves, indicating a stable negative association between frequent game use and short-term academic performance in adolescence. Finally, to investigate the long-term interrelations among game use, self-control, health management, and academic achievement, we estimated parallel-process LGMs. The results indicated that higher initial game use was associated with lower initial levels of self-control, health management, and academic achievement. Moreover, adolescents whose game use increased more rapidly over time showed steeper declines in self-control, greater deterioration in health management, and sharper drops in academic performance. A specific indirect pathway from initial game use to the slope of health management via the linear slope of self-control was statistically significant, suggesting that heavy game use can undermine health management behaviors partly by eroding self-regulation. In contrast, a mediation model specifying the slope of academic achievement as the final outcome did not converge, limiting interpretation of the game use–self-control–achievement pathway. Taken together, the findings demonstrate that the quantitative aspect of game use—how long adolescents play—has meaningful longitudinal implications for the developmental trajectories of self-control, health management, and academic achievement. At the same time, parent–child communication and academic and peer stress displayed relatively stable mean levels, implying that in this sample family and peer relationships functioned more as background contexts than as domains that deteriorate rapidly in tandem with game use. Rather than framing game use solely as a pathological disorder, the results underscore the importance of early monitoring of initial game-use levels and growth rates, as well as preventive interventions aimed at strengthening self-control and digital literacy, to protect adolescents’ health, learning, and family and peer relationships.

This study aims to develop a measurement scale that empirically assesses ethical judgments and behavioral principles required in metaverse environments. As a space characterized by blurred boundaries between reality and virtuality, anonymity, and immersive interaction, the metaverse necessitates distinct practical ethical standards, differing from conventional digital ethics. To this end, the study employed literature review, in-depth interviews, focus group interviews (FGIs), and Delphi techniques to develop items reflecting the fundamental provisions of practical ethics. Exploratory factor analysis and confirmatory factor analysis were conducted to ensure the scale’s validity and structural soundness. The analysis identified five core factors constituting practical ethics in the metaverse: subjectivity, inclusivity, fairness, privacy protection, and autonomy. These factors correspond respectively to key ethical behavioral elements: internal motivation (Factor 1), social expectation (Factor 2), role responsibility (Factor 3), self-regulation (Factor 4), and personal autonomy (Factor 5). The structure of these factors aligns with various theoretical foundations, including practical ethics theory, self-determination theory, and the theory of subjective norms, and is specifically designed to capture the unique interactivity and ethical scenarios within the metaverse. The developed scale is expected to serve as a foundational tool for quantifying ethical standards in metaverse user education, digital citizenship programs, policy design, and technological implementation. It also holds potential for contributing to ethical research across diverse sociocultural contexts in the future.

This study aimed to investigate the changes in nutritional components of six domestically bred soybean cultivars before and after fermentation with Rhizopus oligosporus. Analysis of five vitamins and minerals showed that levels of vitamin B2, vitamin B3, phosphorus, and calcium increased in all cultivars following fermentation, with notable variations among the cultivars. Specifically, the vitamin B2 content in Daepung and Daewonkong increase significantly, by 6.8-fold and 6.7-fold, respectively, compared to pre-fermentation levels. Additionally, Danbaekkong exhibited the highest calcium content after fermentation, at 3.90 mg/g. Before fermentation, soybean oligosaccharides contained 3.4 to 9.0 times more stachyose than raffinose; however, these levels decreased by over 80% across all cultivars after fermentation with Rhizopus oligosporus. The total dietary fiber content rose from 9.28%~11.32% before fermentation to 12.57%~14.86% afterward, though no significant differences were observed among the cultivars. This study confirms that fermentation with Rhizopus oligosporus enhances the nutritional value of domestically bred soybeans, particularly regarding vitamin B2, vitamin B3, calcium, phosphorus, oligosaccharides, and total dietary fiber.

2023년 2월부터 11월까지 부산에서 유통되고 있는 어린 이 기호식품인 과자 105건에 대하여 곰팡이독소 11종(아 플라톡신 B1, B2, G1, G2, 푸모니신 B1, B2, 오크라톡신 A, 제랄레논, 아플라톡신 M1, 데옥시니발레놀, 파튤린)에 대 한 실태를 조사하였다. 영유아용 과자는 38건 중 과자류 7건에서 곰팡이독소가 검출되었다. 검출된 곰팡이독소는 푸모니신 5건(0.8-97.0 μg/kg), 제랄레논 4건(1.6-6.3 μg/kg) 이 검출되었으며, 총아플라톡신, 오크라톡신 A, 아플라톡 신 M1, 데옥시니발레놀 및 파튤린은 검출되지 않았다. 검 출된 시료는 기준이 있는 경우 적합하였으며, 기준이 없는 경우 최대 검출량이 기준의 5.4% 수준으로 오염도가 낮았 다. 일반과자 67건 중 과자류 22건, 곡류가공품 4건에서 곰 팡이독소가 검출되었으며, 푸모니신 14건(0.8-109.6 μg/kg), 제랄레논 11건(1.2-7.0 μg/kg), 오크라톡신 A 7건(0.4-0.8 μg/ kg), 아플라톡신 B1 2건(1.2-1.6 μg/kg)이 검출되었으며, 아 플라톡신 M1, 데옥시니발레놀 및 파튤린은 검출되지 않았 다. 검출된 시료는 기준이 있는 경우 적합하였으며, 기준 이 없는 경우 최대 검출량이 기준의 3.2-16.0% 정도로 오 염도가 낮았다. 곰팡이독소가 2종 이상 검출현황은 영유 아용 과자 중 2건에서 곰팡이독소가 동시에 검출되었으며, 일반과자 중 5건에서 곰팡이독소가 동시에 검출되었다. 2 종 이상의 곰팡이독소에 오염된 시료 중 가장 많은 조합 은 푸모니신과 제랄레논으로 나타났다. 곰팡이독소의 위 해 평가 결과, 영유아용 과자에서 푸모니신과 제랄레논은 1일 섭취한계량의 0.08-1.91% 수준이었고, 일반과자에서 푸모니신과 제랄레논은 1일 섭취한계량의 0.06-1.69% 수 준이었고, 오크라톡신 A는 주간 섭취한계량의 0.05-0.33% 수준이었다. 아플라톡신 B1의 1일 인체노출량은 0.0001- 0.0010 μg/kg b.w./day으로 나타났으며, 영유아용 과자와 일 반과자 모든 시료에서 1-2세의 인체노출량이 가장 높았으 며, 3-5세, 6-11세, 전연령 순으로 낮은 수준을 보였으며 모든 연령에서 위해 우려가 낮은 것으로 나타났다. 본 연 구는 어린이 기호식품인 과자류에 대한 곰팡이독소 오염 실태를 조사함으로써 과자류에 대한 안전성 관리에 필요 한 기초자료로 이용할 수 있을 것이며, 시민들에게 건강한 먹거리 선택에 유용한 정보를 제공할 수 있을 것으로 사료된다.

Yeosu National Industrial Complex is one of Korea’s representative petrochemical industrial complexes where crude oil refining and petrochemical companies are concentrated. According to the results of the 2021 chemical emissions survey, during the process of manufacturing, storage, and transportation at the Yeosu National Industrial Complex, various hazardous chemicals, including hazardous air pollutants, volatile organic compounds and odorous substances are being emitted into the air, affecting the surrounding environment and the health of residents. The Ministry of Environment is applying strengthened standards by designating the Yeosu National Industrial Complex as an air conservation special measure area and establishing odor management areas to manage the air environment. Nevertheless, odor complaints continue to be registered and related complaints increase when turnaround work is carried out. Since air emissions are not counted during periods of turnaround as normal operations are temporarily suspended, it was difficult to establish policies to reduce odor complaints because the source of emissions and emission quantities cannot be ascertained with certainty. In this study, the extensive Yeosu National Industrial Complex was subdivided into 4 areas using a mobile vehicle equipped with PTR-ToF-MS capable of real-time analysis without sample pretreatment being carried out. Measurements were repeated during the day, night, and dawn while moving around the internal boundary of the plant and the boundary of each region where turnaround activities were being carried out. As a result, the recorded measurement for acrylonitrile was the highest at 6340.0 ppb and propyne and propene were measured the most frequently at 128 times each. Based on these results, it will be possible to help reduce emissions through process improvement by efficiently operating air measurement networks and odor surveys that conduct regular measurements throughout the year and providing actual measurement data to the plant. Also, it will help reduce odor complaints and establish systematic air management policies.

With changing dietary trends, active research is underway to substitute rice flour for wheat flour, commonly added to various processed foods. This study aimed to explore whether Baromi2, a floury rice incorporated in the production of Sujebi, can effectively replace wheat flour at appropriate levels based on its physicochemical and cooking characteristics. Baromi2 was categorized based on particle size (100, 140, and 200 mesh) and added in proportions of 10% and 20% relative to the weight of wheat flour. As the amount of Baromi2 increased, the protein and lipid content of the mixed flour also increased. Simultaneously, the dough strength decreased as the noodles became thinner, reducing hardness, gumminess, and chewiness. Additionally, a decrease in particle size increased peak viscosity and breakdown viscosity, whereas setback viscosity decreased. When Baromi2 was added at a 10% ratio, it displayed a low cooking loss, demonstrating desirable characteristics for Sujebi and was considered the most suitable proportion for production. These results provide foundational data for developing various rice-processed products using Baromi2, contributing to expanding consumption and enhancing utility.

This study evaluated the physicochemical characteristics of wheat-flour mixed powders and cooking properties of Sujebi based on the addition of ‘Baromi2’ rice flours for increased expansion of rice consumption. The addition rates at which a roll surface sheet was formed were selected as 0, 10, 20, 30, and 50% based on preliminary experiments with 0-90% addition rates of ‘Baromi2’. Results of physicochemical characterization showed that increasing the addition ratio of ‘Baromi2’ rice flour resulted in increased crude ash and crude fat levels, however crude protein and total starch decreased. The L*-value (lightness) increased with increasing addition ratio of ‘Baromi2’ rice flour; in contrast, a*-value (redness), b*-value (yellowness), and particle size decreased. Results of RVA showed that increasing the addition ratio of ‘Baromi2’ rice flour increased the peak, breakdown, and setback. Regarding textural properties, hardness and chewiness values were significantly reduced with increasing addition ratios of ‘Baromi2’ rice flour. Based on these results, a blending ratio of 20% or less of ‘Baromi2’ is considered suitable for producing Sujebi, and this result serves as basic data for the development of processed rice flour products using ‘Baromi2’.

This study investigated the quality characteristics and optimal conditions of noodles produced by adding Baromi 2 Garu floury rice to wheat flour. The lightness of samples with floury rice increased, while the lightness (L*), redness (a*), and yellowness (b*) decreased after cooking compared to before cooking. The weight, volume, and moisture absorption rate of cooked noodles decreased compared to wheat, but turbidity increased as the amount of rice flour increased. In addition, compared to the control with 20% rice flour, GR-20 (flour replacement by 20% Garu floury rice) with floury rice had lower turbidity, showing less cooking loss. The hardness, gumminess, and chewiness of noodles with floury rice decreased as the floury rice content increased, while springiness, cohesiveness, and adhesiveness increased. The elongation force and distance decreased as the amount of floury rice increased. Therefore, the optimal amount of floury rice to replace wheat flour would be 20%. Adding excessive amounts of floury rice to processed foods requires additional processes, such as adding food additives or changing the processing method to control physical properties.

This study investigated the nutritional characteristics of before and after fermentation of domestic soybean (Glycine max L.) by Rhizopus oligosporus. The soybean storage proteins, β-conglycinin (11S globulin) and glycinin (7S globulin), were the most abundant in Seonyu (SY) and Danbaegkong (DBK), with concentrations of 253.4 mg/g and 193.0 mg/g, respectively. For 11S/7S related to sulfur-containing amino acid, DBK had a value of 0.95, making it the most excellent nutritionally among all the cultivars. The free amino acid content significantly increased from 0.04~10.45 mg/g before fermentation to 1.37~16.95 mg/g after fermentation, and the essential amino acid composition increased, confirming an improvement in protein quality after fermentation. Phytic acid, known as a nutritional inhibitor of soybeans, decreased from 1.66~2.13 g/100 g before fermentation to 0.90~1.58 g/100 g after fermentation, suggesting that mineral absorption inhibition was alleviated. In addition, the trypsin inhibitor content is suppressed by 76.20% to 81.25% after fermentation, which is expected to improve protein utilization in the body. This study confirmed some properties of fermented products by Rhizopus oligosporus using domestic soybeans, and these results are presented to serve as the basic data for establishing new uses of Korean soybean cultivars.

This study was conducted to compare the quality characteristics of commercial tofu products from the market in Korea. Seventeen types of commercial tofu samples were taken and their physicochemical properties, including soluble solid contents, salinity, pH, total acidity and moisture (total solid contents), were analyzed. The hardness of tofu was negatively correlated with the moisture contents of tofu (r=－0.667**). The commercial tofu showed pH 5.80~6.24, total acidity of 0.016~0.034%, soluble solids of 1.50~3.45 °Brix, salinity of 1.20~2.30%, and moisture content of 79.91~87.57%, respectively. All 17 tofu samples sold in the Korean market were prepared using crude MgCl2 and sea water as a coagulant. The quality characteristics vary depending on the constituent’s of soybeans, and the ratio and amount of coagulants of tofu used. The origin of soybean seeds affected the yellowness of tofu; tofu made from imported soybean showed a higher b value than domestic soybean. These results are expected to be useful for understanding trends in the domestic tofu industry.

In vitro digestibility and protein digestibility corrected amino acid scores (PDCAAS) were investigated to verify the availability of protein in various Rhizopus oligosporus fermented products of domestic soybean (Glycine max L.) cultivars. Danbaegkong (DBK), Daepung (DP), Daewonkong (DWK), Saedanbaek (SDB), Seonyu (SY), and Cheongja4ho (CJ4) were used as raw samples, which were fermented using commercially available Rhizopus oligosporus for 48 h. All cultivars showed increased crude protein content after fermentation. The crude protein content of DBK and SDB was significantly higher than that of the other samples (55.12% in DBK and 54.22% in SDB) (p<0.001). CJ4 had the highest alanine content of 28.88 mg/g (p<0.001), and no significant difference in cysteine content was detected among the cultivars. In most of the fermented samples, the in vitro digestibility was 0.9 or higher, indicating high protein in the fermented samples. However, it is considered that restrictions on digestion are low. In DWK, the amino acid content and PDCAAS, which together indicate protein quality, were 0.917 and 0.855, respectively, confirming that it was the best cultivar to provide the raw material for fermentation. In conclusion Rhizopus oligosporus fermented soybean products can be considered a prospective source of protein with high utility value.

In existing ceramic mold manufacturing processes, inorganic binder systems (Si-Na, two-component system) are applied to ensure the effective firing strength of the ceramic mold and core. These inorganic binder systems makes it possible to manufacture a ceramic mold and core with high dimensional stability and effective strength. However, as in general sand casting processes, when molten metal is injected at room temperature, there is a limit to the production of thin or complex castings due to reduced fluidity caused by the rapid cooling of the molten metal. In addition, because sodium silicate generated through the vitrification reaction of the inorganic binder is converted into a liquid phase at a temperature of 1,000 °C. or higher, it is somewhat difficult to manufacture parts through high-temperature casting. Therefore, in this study, a high-strength ceramic mold and core test piece with effective strength at high temperature was produced by applying a Si-Na-Ti three-component inorganic binder. The starting particles were coated with binary and ternary inorganic binders and mixed with an organic binder to prepare a molded body, and then heat-treated at 1,000/1,350/1,500 °C to prepare a fired body. In the sample where the two-component inorganic binder was applied, the glass was liquefied at a temperature of 1,000 °C or higher, and the strength decreased. However, the firing strength of the ceramic mold sample containing the three-component inorganic binder was improved, and it was confirmed that it was possible to manufacture a ceramic mold and core via high temperature casting.

Consumer demand for imported and craft beer is increasing. Almost all the malt used by craft beer companies is imported. This study sought to develop a malting technology to expand the use of domestic barley, the main raw material for beer, and to examine its influence on the quality of domestic malt. The Hopum cultivar of beer barley was purchased and used at the Jeollanam-do Seed Management Center. A pilot-scale malting facility built by the National Institute of Crop Science was used. One sack (40 kg) of barley was sieved through screening sieves, and the barley was classified according to size (3.1, 2.8, 2.5, 2.2, and 2.2 mm), with the size-related composition being 18.1, 48.9, 23.3, 6.4, and 1.0%, respectively. The malt yields were 89.0, 87.6, 86.6, 82.2, and 76.1%, respectively. The coleoptiles elongation decreased as the barley size decreased. The protein content of malt tended to be high at small particle sizes of 2.2 mm. The soluble solid content of wort prepared from malt revealed good values of 17.4-17.5oBx, except for 15.3oBx for particles <2.2 mm in size. According to barley size in the malting process, these findings should be valuable quality indicators of malt.