This study evaluated the impact of sowing dates on the growth, yield, and nutritive quality of three corn cultivars including Gwangpyeongok, Dacheongok, and Shinhwangok. Plant height and total yield components declined with delayed sowing across all cultivars. Gwangpyeongok achieved the highest plant height (289 ± 14 cm), grain yield (9,108 ± 82 kg/ha), and total yield (18,973 ± 2,560 kg/ha) at the April 29 sowing. Dacheongok recorded the highest stover yield (17,227 ± 137 kg/ha) and total yield (22,236 ± 1,053 kg/ha) on May 13. Shinhwangok reached its maximum total yield (19,158 ± 604 kg/ha) at May 13 but showed the sharpest declines by May 16. Nutritional quality also deteriorated with later sowing. In stover, crude protein (CP) declined to 3.58% in Shinhwangok at May 16, accompanied by a rise in neutral detergent fiber (NDF) to 69.9%. In contrast, Dacheongok maintained stable CP levels (5.27–5.60%) and the lowest fiber fractions. Gwangpyeongok exhibited the highest stover CP at April 29 sowing, along with the lowest NDF and acid detergent fiber (ADF) contents. Grain CP was highest in Gwangpyeongok (8.1 ± 0.4%) and Shinhwangok (9.6 ± 0.9%) at April 29, while Dacheongok showed its maximum grain CP (8.0 ± 0.3%) at the same sowing date, coupled with relatively low fiber content. Overall, the findings highlight that timely sowing is crucial for achieving both high yield and optimal nutritive quality in maize. For Gwangpyeongok and Dacheongok, sowing from late April to mid-May provided the best balance between yield and nutritional quality. In Shinhwangok, the highest stover, grain, and total biomass yields were obtained at the May 13 sowing.

The purpose of this study is to examine the effects of sowing dates on the growth, yield, and forage quality of two triticale cultivars, Joseong and Hanmiso-1ho. Field experiments were conducted with sowing dates ranging from September 25 to November 13, 2023. The results indicate that both cultivars and sowing date significantly influence growth characteristics, dry matter yield, and nutritional composition. The highest yields were obtained from the earliest sowing (September 25), with Joseong producing 10,979 ± 366 kg/ha and Hanmiso-1ho 12,201 ± 2,124 kg/ha. Yields remained relatively high on October 5 and 16 sowings but declined sharply after October 25, reaching the lowest levels on November 13 (Joseong 4,991 ± 458 kg/ha; Hanmiso-1ho 6,353 ± 338 kg/ha). Delayed sowing increased plant height but reduced forage biomass. Forage quality also varied with the sowing date. Crude protein (CP) ranged from 8–11%, with higher values in early sowing (10.7% for Joseong, 10.3% for Hanmiso-1ho) and lower at mid to late sowing dates. Fiber content such as NDF and ADF levels increased with the sowing dates delayed, but declined slightly with the November sowing dates. Overall, end September to early October sowings provide optimal yield and forage quality for both triticale cultivars.

본 연구는 Peperomia 속 두 종(P. argyreia ‘Watermelon’과 P. obtusifolia ‘Variegata’)을 대상으로 실내환경에서 광질(백 색, 청색, 적색)이 생장, 색소 조성, 무늬 면적에 미치는 영향을 분석함으로써, 적정 광질 조건을 탐색하고자 하였다. 생장 반응 은 엽장, 엽폭, 초장, 엽수 등 모든 지표에서 통계적으로 유의한 차이가 나타나지 않았으며(p ≥ 0.05), 이는 실내 광도 수준에서 광질 변화가 생장에는 제한적인 영향을 미침을 나타낸다. 그러 나 색소 조성과 무늬 면적에서는 뚜렷한 차이가 확인되었다. P. obtusifolia ‘Variegata’는 적색광 처리 시 chl a와 b, 총 car 함량이 감소하고, 무늬 면적 또한 유의하게 줄어드는 반응 을 보였다. 반면 청색광에서는 chl a와 car 함량 증가, chl a/b 비율 상승과 더불어 printed area의 안정적인 유지가 확인되 어, 청색광이 생리적 활성 유지에 유리한 광질로 평가되었다. 이러한 결과는 무늬의 발현 방식에 따라 광질 반응성이 다르며, 실내 재배 시 광질 조절이 관상성과 생리적 안정성 확보를 위한 핵심 전략이 될 수 있음을 보여주었다.

본 연구는 요양보호사의 긍정심리자본과 서비스 질 관계에서 직업윤리 의식과 직무스트레스의 직렬 이중 매개효과를 검증하고자 하였다. 요양 보호사를 대상으로 설문을 진행하였으며 529명을 대상으로 SPSS 26.0 과 PROCESS Macro v4.2를 활용하여 빈도분석, 신뢰도, 직렬 이중 매 개효과를 분석하였다. 연구 결과 요양보호사의 긍정심리자본은 서비스 질을 높이는 직접적인 효과가 검증되었으며, 긍정심리자본이 높을수록 직업윤리의식이 높아지고 서비스 질이 높아진다는 또 다른 경로를 함께 검증한 것이다. 이는 요양보호사의 긍정심리자본을 단일효과에서 벗어나 동기요인인 직업윤리의식과 저해요인인 직무스트레스가 어떠한 작동을 통해 서비스 질로 이어지는가에 대한 다층 모델을 제시하였다는 데 의의 가 있다. 연구 결과에 따라 요양보호사 대상 긍정심리자본 평가 및 증진 프로그램을 개발·실시하고 직업 윤리교육을 정례화하며 실질적 스트레스 관리와 심리지원 체계를 구축해야 함을 제시하였다.

This study investigated the seasonal water quality characteristics of two key environmental flow sources for the Gwangju Stream: the Yeongsan River water supply and effluent from a sewage treatment plant. Monitoring data collected between 2019 and 2023 were analyzed for both sources, and field surveys from October 2023 to June 2024 examined confluence points where environmental flows entered the Gwangju Stream, measuring both main-stream and inflow waters. The Yeongsan River supply recorded its highest spring organic matter levels (mean BOD: 5.2 mg L-1; maximum: 8.7 mg L-1), while the sewage treatment plant effluent exhibited pronounced seasonal variation in total nitrogen (T-N), ranging from a summer low of 8.2 mg L-1 to a winter high of 13.8 mg L-1. Upstream water quality remained stable; however, downstream BOD increased annually by 8.2%, and total phosphorus (T-P) peaked sharply in summer (0.567 mg L-1). Field survey results indicated that in spring, T-N increased by up to 495%, BOD by 182%, and T-P by 290%; in winter, T-N rose by 239%, BOD by 164%, and COD by 73%. These findings reveal marked seasonal variability in the influence of environmental flow sources, with T-N showing the most substantial increase in spring. The results highlight the need for targeted nutrient management strategies, such as increasing the proportion of the plant’s effluent in spring to stabilize nutrient loads and improving its biological treatment efficiency in winter to reduce T-N concentrations. Season-specific measures of this kind can improve water quality and help sustain the ecological integrity of the Gwangju Stream.

This study analyzed policy measures to comprehensively achieve two goals: carbon neutrality in buildings and optimization of indoor air quality. While buildings account for approximately 40% of total energy consumption and greenhouse gas emissions, and present-day individuals spend 90% of their daily lives indoors, both goals are critically important. However, these objectives often conflict with each other, and current policies have limitations in effectively addressing this complex relationship. Analysis of related policies, including the Green Building Creation Support Act and the Indoor Air Quality Management Act, revealed significant drawbacks such as the lack of an integrated approach due to policy fragmentation, insufficient consideration of lifecycle carbon emissions, imbalance in economic incentive structures, and rigidity in technical standards. To overcome these challenges, this study proposes innovative improvement measures, including the following: establishing an integrated policy framework, introducing a multi-layered air quality management system, expanding performance-based design that simultaneously considers energy efficiency and indoor air quality, developing region-specific policies, implementing AI-based self-assessment systems, mandating green space ratios, controlling high-radon concentration areas, and expanding government incentives.

쉰다리는 제주도에서 쌀 또는 보리와 누룩을 이용해 짧 은 발효 과정을 거쳐 생산되는 전통적인 저알코올 발효 음료이다. 본 연구에서는 제주에서 시판되는 쉰다리의 품 질 특성 및 항산화 활성을 조사하였다. 조사 항목에는 pH, 당도(oBrix), 총산도, 유리당, 유기산, 총 폴리페놀 함량, 총 플라보노이드 함량, FRAP 활성, DPPH 자유 라디칼 소거 능이다. 쉰다리의 pH는 pH 3.25-3.45 범위였고, 당도는 10.6-13.3 oBrix 범위로 나타났다. 총산 함량은 비살균 제 품(0.55-0.67% w/v)이 살균 제품(0.43-0.46% w/v)보다 더 높게 측정되었다. 이러한 차이는 발효 과정 중 젖산은 유 의한 변화가 없었으나 초산이 유의하게 증가한 데 기인한 다. 비살균 제품들의 총 폴리페놀 함량(332.68-371.88 mg GAE/g)과 총 플라보노이드 함량(154.86-261.10 mg QE/g) 은 살균 제품들(각각 452.26-589.69 mg GAE/g, 242.74- 383.61 mg QE/g)보다 낮게 나타났다. 비살균 쉰다리인 C 제품은 FRAP 활성(163.89 μM TE/g)과 DPPH 자유 라디 칼 소거능(43.45%)에서 가장 높은 항산화 활성을 보였다. 본 연구의 결과는 쉰다리가 기능성 음료로서의 가능성을 가지고 있음을 시사한다.

하수처리장 유출수의 수질 예측은 수질 사고의 사전 대응 및 처리장의 안정적인 운영을 위해 필수적인 요소이다. 최근 머신러닝을 활용한 예측 모델링에서 예측 성능 향상과 과적합 방지를 위해 다양한 교차 검증법과 하이퍼파라미터 최적화 기법이 활용되고 있으나, 하수처리장 데이터는 시간적 의존성과 급격한 변동성이 내재되어 있어 과적합에 취약하고 안정적인 모델 구축에 어려움이 따른다. 본 연구에서는 이러한 데이터 특성을 효과적으로 반영할 수 있는 최적의 모델링 파이프라인을 구축하고자 하였으며, XGBoost 모델을 기반으로 유출수 내 총질소 농도를 예측하였다. 예측 성능 평가 지표로는 평균 제곱근 오차(Root Mean Square Error, RMSE), 결정계수(coefficient of determination, R2), RMSE 오차 개선율(the rate of improvement on RMSE, RIRRMSE) 그리고 계산 시간을 사용하였다. 기본적인 Hold-out 방식의 성능을 기준으로 K-fold, 시계열 교차 검증(Time Series Cross Validation, TSCV), 블록 시계열 교차 검증(Blocked Time Series Cross Validation, BTSCV) 기법의 예측 성능을 분석한 결과, BTSCV는 인접한 데이터만을 고려하는 방식으로 시간적 의존성과 급변 특성을 효과적으로 반영하여 가장 높은 RIR(36.37%)을 기록하였다. 또한, 하이퍼파라미터 최적화(그리드 서치와 베이지안 최적화) 기법과의 다양한 교차 검증법의 조합을 통해 모델 성능과 과적합 방지 효과를 분석한 결과, BTSCV와 베이지안 최적화의 결합은 짧은 계산 시간(364.64초)과 함께 가장 높은 RIR(64.93%)을 보였으며, 훈련 및 평가 데이터 간 성능 차이도 최소화되어 일반화된 예측 모델로서의 효과성이 입증되었다. 따라서 본 연구는 하수처리장 시계열 데이터의 특성에 적합한 BTSCV와 베이지안 최적화 기법을 결합한 모델링 파이프라인 전략을 제안하며, 향후 실시간 수질 모니터링 및 하수처리장 운영 효율성 제고에 기여할 수 있을 것으로 기대된다.

This study investigates the potential market demand and the effects of consuming senior-friendly foods on the nutritional status and quality of life of older adults in South Korea, which has rapidly become a super-aged society. Utilizing data from a 2024 field study, a Difference-in-Differences (DID) analysis was employed to evaluate the impact of senior-friendly food intake on calorie and nutrient supplementation, as well as improvements in quality of life. The findings reveal a substantial potential market, with 11.7 to 16.2% of individuals aged 75 and over expressing purchase intentions. Significant improvements were observed in both the Mini Nutritional Assessment (MNA-SF) and the Nutrition Quotient for Elderly (NQ-E) scores after the consumption of senior-friendly foods. Further, the intake increased daily calories by an average of 322.9 kcal, protein intake by 14.2 g, and fat intake by 12.1 g. The utility weight, indicating quality of life, also significantly increased by 0.037. Policy directions should prioritize promoting the senior-friendly food market to improve nutritional intake and quality of life among the rapidly growing older adult population, as evidenced by the significant positive effects observed in this study.

This study examined the quality characteristics of rice layer cakes prepared using various levels of allulose (ALL). ALL was used to substitute 0% (control group), 25% (ALL-25 group), 50% (ALL-50 group), 75% (ALL-75 group) and 100% (ALL- 100 group) of white sugar (WS) in the manufacture of rice layer cake. The substitution of WS with ALL decreased the pH of the cake batter but increased its specific gravity (p<0.001). The ALL-100 group exhibited higher moisture content than the control (p<0.05), and baking loss increased with increasing ALL levels (p<0.01). The volume index of the cake decreased significantly as the proportion of ALL increased (p<0.001). Low lightness, high redness, and high yellowness were observed in the experimental groups at higher proportions of ALL (p<0.001). The ALL-100 group exhibited significantly higher hardness, adhesiveness, cohesiveness, springiness, gumminess, and chewiness than the other groups (p<0.05). Sensory evaluation revealed that cakes with higher ALL levels had stronger perceived intensity with respect to “color,” “sweet aroma,” and “salty taste.” The acceptance test indicated that the ALL-25 group was comparable to or more acceptable than the control in all attributes except for color.

This study investigated the quality characteristics of gochujang based on the amount of green onion added and aimed to propose standardizing the green onion extract content in the gochujang manufacturing process. Green onion extract was used as a substitute for distilled water at 0% (CON), 4% (GO1), 7% (GO2), 10% (GO3), and 14% (GO4) of the total weight of distilled water. Among the quality characteristics, the pH significantly increased only in the GO4 group (p<0.05). Conversely, the moisture content initially decreased before increasing again. The total available solids and Brix significantly increased (p<0.001), as did salinity (p<0.05). In terms of color value, the L value (brightness) significantly increased, while the a value (red) and b value (yellow) significantly decreased (p<0.001). Regarding antioxidant activity, the polyphenol, DPPH, and ABTS+ radical scavenging activities significantly increased with higher extract content (p<0.001), and the flavonoid content also increased significantly. As the extract content increased, overall acceptance improved significantly, with the characteristic intensity evaluation scoring highest in the GO3 group (p<0.001).

Purpose: This study applied a mixed-methods design to examine the effects of the nurse shift system improvement pilot project, organized by the Ministry of Health and Welfare, on ward nurses’ quality of life, job satisfaction, and patient safety nursing activities, as well as to explore their overall evaluation of the project through in-depth interviews. Methods: Using a mixed-methods approach, this study simultaneously conducted quantitative analyses of ward nurses’ quality of life, job satisfaction, and patient safety nursing activities, along with qualitative research through in-depth interviews to explore overall perceptions of the nurse shift system improvement pilot project. Results: Patient safety nursing activities showed a significant positive correlations with quality of life (r=.24, p=.017) and job satisfaction (r=.21, p=.038). There was also a significant positive correlation between quality of life and job satisfaction (r=.63, p<.001). As a result of the qualitative analysis, eight facilitating factors and five hindering factors related to the pilot project were identified. Conclusion: Through the research, the effectiveness of the pilot project and the factors influencing nurses were identified. Accordingly, strategies are needed to enhance patient safety nursing activities by improving nurses’ quality of life and job satisfaction in pilot project wards.

Efforts to mass-produce high-quality graphene sheets are crucial for advancing its practical and industrial applications across various fields. In this study, we present an innovative electrochemical exfoliation method designed to enhance graphene quality and increase yield. Our approach combines two key techniques: expanding the tightly packed graphite interlayer used as the electrode medium and precisely controlling voltage polarity. The dual-exfoliation technique optimizes the use of anions and cations of varying sizes in the electrolyte to facilitate meticulous intercalation, allowing ions to penetrate deeply and evenly into the graphite interlayer. The newly designed dual-exfoliation technique using biased switching polarity minimizes the generation of oxygen-containing radicals, while the incorporation of expanded graphite accelerates exfoliation speed and reduces oxidation, maintaining high graphene purity. With these improvements, we produced 1–3 layer graphene sheets with minimal defects ( ID/IG ≈ 0.13) and high purity (C/O ratio ≈ 20.51), achieving a yield 3.1 times larger than previously reported methods. The graphene sheets also demonstrated excellent electrochemical properties in a three-electrode system, with an electrical conductivity of 92.6 S cm− 1, a specific capacitance of 207.4 F g− 1, and a retention of 94.8% after 5,000 charge/discharge cycles, highlighting their superior stability and performance.

The postharvest quality of cut flowers often declines during transportation, especially under dry storage conditions. Therefore, incorporating preservative solutions during shipment is vital for extending the vase life of high-value cut flowers. Among commonly used additives, sucrose (Suc) and Floralife (FL), a commercial preservative, have demonstrated efficacy in maintaining vase life. Oxygen nanobubbles (O2NB) and ozone nanobubbles (O3NB), which are nanoscale gas-filled bubbles in aqueous media, have been proposed as antimicrobial agents for use in preservative solutions applied to cut flowers. This study examined the effects of seven preservative treatments on the postharvest performance of cut Cymbidium ‘Lovely King’ during simulated transport. Treatments included tap water (control), Suc, FL, O2NB, O2NB combined with Suc (O2NBS), O3NB, and O3NB combined with Suc (O3NBS). Cut stems were placed in floral water tubes filled with the respective solutions and stored in a cold chamber at 5°C for 7 days to simulate transport conditions. Among the treatments, O2NB resulted in the longest vase life of 21.0 days, significantly longer than that under O2NBS (14.3 days). Additionally, the O2NB solution exhibited the lowest bacterial count (4.9 log 10 CFU mL-1) compared with other treatment solutions. Stems treated with O3NB maintained the highest relative fresh weight throughout the experiment. Initial water uptake was 8.4 g and 7.6 g for the O3NB and O2NB treatments, respectively. These findings indicate that O2NB is an effective transport preservative for enhancing postharvest quality and extending the vase life of cut Cymbidium ‘Lovely King.’

본 연구는 절화 장미‘All For Love’에 대해 과산화초산 (peracetic acid, PAA)의 보존용액 적용 가능성과 적정 처리 농도를 구명하고자 수행되었다. 보존용액 처리는 Distilled water(DW), PAA 50, 100, 200μL·L-1, FloraLife 1%로 하였 다. 절화수명은 대조구 DW(5.27일)에 비해 PAA(5.87~6.20 일)와 FloraLife(5.87일) 처리구에서 절화수명 연장효과가 있었 다. 모든 처리구에서 80% 이상 꽃목 굽음(Bent neck)과 20% 이상 꽃잎 청변화(Blueing) 현상이 나타났다. 화색 변화율과 잎의 엽록소 함량은 처리간 차이가 없었다. 화폭변화율의 경 우, DW(135%)보다 PAA 50μL·L-1(155%), 100μL·L-1(154%), 200μL·L-1(161%) 처리구에서 높은 개화율을 보였다. 상대생체 중은 DW와 FloraLife 처리구에서는 2일, PAA 처리구에서는 3일까지 증가 후 감소하였다. 수분균형은 DW에서 가장 빠르게 (-)의 값을 나타냈고, PAA 50μL·L-1 처리구에서 가장 길게 수분 균형이 유지되었다. PAA와 FloraLife 처리구에서 보존용액과 줄기 절단면 모두 세균이 검출되지 않았다. 결론적으로 PAA 50μL·L-1 처리는 DW에 비해 장미의 절화수명 연장 및 품질 유지에 효과적이었다.

The number of significant issues on many welding processes are often connected to high productivity and manufacturability at low costs. The research on welding processes in the literature has reported several research activities, but there is still scope for improvement in most industrial settings. The primary goal of this research is to determine the best super-TIG welding settings to use for groove welding. First, in order to determine the quality characteristics and risks associated with them, concepts and frameworks of quality by design (QbD) which is a new standard in pharmaceutical area in order to improve drug qualities were integrated into this process optimization. Second, stepwise experimental design approaches including a factorial design as well as a response surface methodology (RSM) were customized and performed for this specific automated super-TIG welding process. Third, based on experimental design results, the optimal operating conditions with both design space (i.e., acceptable range of operating conditions) and safe operating space (i.e., safe range of operating conditions) were obtained. Finally, a case study including QbD steps, stepwise experimental design approaches, design and operating spaces, the optimal factor settings, and their association validation results was conducted for verification purposes.