2022년 1월부터 11월까지 부산지역에서 유통 중인 신선 농산물 210건을 대상으로 리스테리아균 분포 현황 및 병 원성 여부를 조사하였으며, 분리된 균주를 대상으로 혈청 형 및 유전자 지문분석을 통해 역학적 연관성을 확인하였 다. 조사 대상 신선농산물에서 총 40건의 리스테리아균이 검출되었으며, Listeria monocytogenes 등 4종의 리스테리 아균이 검출되었다. 이 중 L. innocua가 22건, L. monocytogenes 10건, L. grayi 6건, L. rocourtiae 2건으로 나타났으며, 이 중 식중독을 유발하는 L. monocytogenes균 은 팽이버섯에서만 검출되었다. L. monocytogenes의 병원 성을 유발하는 유전자인 iap, prfA, inlA, inlC, inlJ 및 hly 6종에 대한 분석 결과, 총 10개 균주 중 6개 균주에서 iap 등 6종의 병원성 유발 유전자가 검출되었으며, 4개 균주 에서 hly를 제외한 5종의 유전자가 검출되어 식중독 발생 잠재위험이 있음이 확인되었다. 지역 유통 식재료에 분포 하는 L. monocytogenes의 유전학적 유사도 및 오염원 추 이를 확인하기 위해 신선농산물에서 분리한 L. monocytogenes 10균주 및 2022년 부산지역 유통 가금류에 서 분리한 L. monocytogenes 2균주를 대상으로 혈청형 분 석 및 PFGE를 실시한 결과, 신선농산물 분리균주의 혈청 형은 1/2a 및 1/2b 두 가지 serotype으로 확인되었으며, 가 금류 분리균주는 모두 1/2a형으로 나타났다. 유전자지문 분석결과, 전체 균주의 유사도는 100-45.7%로 나타났고, 이 중 100% 상동성을 보인 균주들은 동일 생산농장 또는 동일지역 유래 팽이버섯에서 분리되어 오염원의 출처가 같음을 추측할 수 있었다. 신선농산물 분리균주와 유통 가금육 분리균주와의 유사도 확인 결과, 일부 팽이버섯 분 리균주와 가금육 분리균주의 유사도가 90.9-84.6%로 나타 났다. 농산물 및 축산물 생산시설간 오염원 이동 및 교차 가능성을 유추할 수 있었다.

To produce super sweet corn sikhye, substituted for sweetener, the ratio of rice and super sweet corn was adjusted and processed with complex enzymes during saccharification, and their physicochemical and sensory properties were analyzed. The soluble solid content of the control and Corn-5 showed significantly high content at 13.50 °Brix, and the reducing sugar content of Corn-5 showed the highest content at 9.45%. The control showed the lowest free sugar content among all the experimental groups, excluding maltose content. In the enzyme-treated corn sikhye group, as the amount of super sweet corn increased, the content of sucrose decreased and the contents of glucose and fructose increased. The content of ascorbic acid and polyphenol compounds increased as the amount of super sweet corn increased. DPPH and ABTS radical scavenging abilities increased with increasing ratio of super sweet corn and enzyme treatment compared to the control. In the case of sensory evaluation, Corn-3, which substituted 30% of super sweet corn for rice and treated with enzymes, showed higher evaluations in taste, sweetness, and overall preference than those of the control.

화장품 소재는 안전성이 무엇보다 중요시된다. 화장품에 사용되는 기존의 보존제인 PE에 대장 균 효소 β–gal을 이용하여 안전성이 증가된 PE-gal을 생합성하였다. 화장품 소재로 사용하기 위해 생합 성된 생성물인 PE-gal의 피부 흡수도를 기존의 보존제인 PE와 비교하기 위해 Franz Diffusion cell Assay 시스템을 이용하여 경피투과도를 측정하였다. 같은 질량농도의 시료를 사용하였을 때 PE의 Flux 값, Kp 값은 시간이 지날수록 증가하는 것으로 나타났으나 PE-gal은 투과도를 측정할 수 있을 만큼 투과되지 못 하였다. 이는 PE의 피부투과도가 생합성된 PE-gal 배당체보다 높다는 것을 나타낸다. Marzulli 등에 따라 Kp 값을 이용하여 투과 정도를 확인하였을 때 PE의 투과속도는 1mg/mL의 농도에서 느림(slow)으로 측정 되었다. 따라서 배당체 형태의 PE-gal은 PE에 비해 경피 투과도가 현저히 낮게 나타났다.

세계 각국은 온실가스 배출을 줄이기 위하여 활발한 노력을 하고 있다. 한국도 노후화된 석탄발전을 폐지하고 LNG 발전으로 전환하는 정책을 추진하고 있다. 그러나, 한국은 가스터빈 제작 기술이 국산화되지 않아서 해외 제작사로부터 전량 수입하여 설치하고 있다. 따라서, 본 논고에서는 가스터빈 발전산업에 대한 국내·외 환경을 살펴보고, 이를 기반으로 PEST-SWOT-AHP 방법론을 적용하여 한국형 가스터빈 기술개발 및 보급 확대 추진전략을 제안하였다. 연구결과, 한국형 가스터빈 기술개발과 보급 확대 전략은 1) 가스터빈 기술개발 및 사업화 촉진을 위한 발전공기업의 역할 강화, 2) 온실가스 감축을 위한 LNG 발전 비중 확대, 3) 정부의 적극적인 가스터빈 산업 생태계 조성 노력, 4) LNG 발전소 건설에 대한 국민 공감대 형성 등으로 요약할 수 있다.

High-Manganese (Mn) austenitic steel, with over 24 wt% Mn content, offers outstanding mechanical properties in cryogenic settings, making it a potential replacement for existing cryogenic materials. This high manganese steel exhibits high strength, ductility, and wear resistance, making it promising for applications like LNG tanks, flanges, and valves. To operate in cryogenic environments, hot forging and heat treatment processes are vital, especially in flange production. The cooling rate during high-temperature cooling after hot forging plays a critical role in influencing the microstructure and mechanical properties of high manganese steel. The rate at which cooling occurs during this process influences the size of the grains and the distribution of manganese and consequently has an impact on mechanical properties. This study assessed the microstructure and mechanical properties based on different cooling rates during the hot forging of High-Mn steel flanges. Comparing air and water cooling after hot forging, followed by heat treatment, revealed notable differences in grain size. These differences directly impacted mechanical properties such as tensile strength, hardness, and Charpy impact property. Understanding these effects is crucial for optimizing the performance and reliability of High-Mn steel in cryogenic applications.

Al2O3 has excellent sintering properties and is important in semiconductor manufacturing processes that require high-temperature resistance and chemical inertness in a plasma environment. In this study, a comprehensive analysis of the chemical characteristics, physical properties, crystal structure, and dispersion stability of three commercially available Al2O3 powders was conducted. The aim was to provide a technological foundation for selecting and utilizing appropriate Al2O3 powders in practical applications. All powders exhibited α-Al2O3 as the main phase, with the presence of beta-phase Na2O-11Al2O3 as the secondary phase. The highest Na+ ion leaching was observed in the aqueous slurry state due to the presence of the secondary phase. Although the average particle size difference among the three powders was not significant, distinct differences in particle size distribution were observed. ALG-1SH showed a broad particle size distribution, P162 exhibited a bimodal distribution, and AES-11 displayed a uniform unimodal distribution. Highconcentration Al2O3 slurries showed differences in viscosity due to ion release when no dispersant was added, affecting the electrical double-layer thickness. Polycarboxylate was found to effectively enhance the dispersion stability of all three powders. In the dispersion stability analysis, ALG-1SH exhibited the slowest sedimentation tendency, as evidenced by the low TSI value, while P162 showed faster precipitation, influenced by the particle size distribution.

본 연구는 일회성 발목가동성 운동프로그램이 만성적인 발목불안정성(CAI)에 나타나는 발목가 동범위와 통증 수준에 미치는 영향을 확인하는데 목적이 있다. 연구 대상자는 발목불안정성 설문지 검사에 서 좌, 우측 평균 점수가 24점 이하인 성인여성 20명을 선정 하였으며 집단은 일회성 발목 가동성 운동프 로그램 집단(Ankle mobility exercise program, AE, n=10)과 대조군(CON, n=10)으로 구분하였다. AE 처 치는 일회성 운동에 대한 반응을 확인하기 위해 좌·우측 발목을 각각 1회(20분) 실시하였으며 처치 전후 발목불안정성 검사, 통증 및 발목가동범위를 확인하였다. 먼저 AE 프로그램을 실시한 AE 집단의 통증 수 준은 사전과 비교하여 사후 유의하게 감소하는 것으로 나타났다(p<.01). 또한 AE 프로그램 처치한 AE 집 단에서 배측굴곡이 사전과 비교하여 증가하는 것으로 나타났다(p<.05). 이러한 결과를 종합해 보면 일회성 발목 가동성 운동 프로그램은 CAI에서 나타나는 발목 통증과 발목의 가동범위를 개선시켜 결과적으로 발 목 불안정성을 완화시킬 수 있는 효과적인 운동 중재 방법이라고 생각된다.

In alignment with South Korea's “3020 Renewable Energy Expansion Plan,” this study focuses on the developing large-scale floating wind turbines. It addresses the challenges of increased size and cost in floating structures for wind turbines over 10MW. This paper details the preliminary design of a novel floating substructure utilizing composite materials(ie, EVA). Structural analysis was performed using ABAQUS, accounting for both typical and extreme wind conditions. Results from the analysis validate that the substructure design is adequately feasible for implementation.

Since ships are exposed to noise and vibration for a long time in seas isolated from land, the stress of workers is high, requiring studies on the improvement of the problem. In addition, the health of crew members on fishing vessels, unlike commercial ships, carrying out fishing activities is closely related to fishing performance. However, considering that most of IMO's guidelines apply to merchant ships, provisions should be made for vibration in accommodation areas of fishing vessels. Accordingly, this study, applying the revised ISO 20283-5:2016 standard and through experiment, investigated the vibration characteristics of the accommodation area for each operating conditions of a 1000-ton trawler fishing vessel. Within the scope of the study and the full-ahead mode, the vibration was highest in the engine control room (4.17mm/s) while the acceptable standard was satisfied sufficiently in all conditions. Application of the merchant vessel vibration standard to fishing vessel is expected to improve the working environment of fishing vessel crew members.

본 연구는 희귀난치 질환 자녀를 둔 가족의 생활 실태와 지원 욕구를 파악하여 지원방안을 모색하는 데 목적이 있다. 이를 위해 2020년 기준 전국의 희귀난치 환아 가족 약 169천 명 중 할당표본추출(quota sampling) 을 통해 모집된 총 263명을 대상으로 설문조사를 하였다. 그 결과, 희귀 난치 환아 가족의 주양육자는 여성으로 자녀 돌봄 및 간병 비중이 높았 고, 치료비지출로 인한 경제적인 부담이 매우 높았다. 전체 삶의 질 평 균 및 삶의 질 하위요인 전반에서 보통 이하의 인식수준을 보였고, 교 육 현장이나 과정에서 자녀의 질병에 대한 인식과 대처 관련 어려움이 큼을 확인하였다. 희귀난치 질환 및 자녀의 재학 상태에 따른 인식수준 도 매우 낮은 수준이었다. 이런 실태에 근거하여 가족지원을 위한 다차 원적인 지원방안을 제언하였다.

To improve usability of super sweet corn, extracts were prepared with hydrolytic enzyme and changes in physicochemical and antioxidant properties were analyzed. Soluble solids and reducing sugars contents were higher in all enzyme treatment groups than in the control. When enzyme treatment time increased, contents of soluble solids and reducing sugars were also increased. There was no significant difference in lightness between treatment groups, with redness showing the highest value in the control and yellowness showing the highest value in the invertase treatment group. Free sugar content in the control was the lowest. However free sugar content in the enzyme combination treatment group was increased by more than four times compared to that in the control. Contents of ascorbic acid, flavonoids and polyphenols were higher in the enzyme treatment group than in the control. In particular, the enzyme combination treatment group showed the highest content. DPPH and ABTS radical scavenging abilities were significantly higher in all enzyme treatment groups than in the control. Radical scavenging abilities of cellulase treatment group and enzyme combination treatment group showed high activity. The activity increased when enzyme treatment time increased. The combined enzyme treatment method for super sweet corn was suitable for food processing.

Many changes in the scale and structure of the Korean rice cropping system have been made over the past few decades. Still, insufficient research has been conducted on the sustainability of this system. This study analyzed changes in the Korean rice cropping system’s sustainability from a system ecology perspective using an emergy approach. For this purpose, an emergy table was created for the Korean rice cropping system in 2011, 2016, and 202, and an emergy-based indicator analysis was performed. The emergy analysis showed that the total emergy input to the rice cropping system decreased from 10,744E+18 sej year-1 to 8,342E+18 sej year-1 due to decreases in paddy field areas from 2011 to 2021, and the proportion of renewable resources decreased by 1.4%. The emergy input per area (ha) was found to have decreased from 13.13E+15 sej ha-1 year-1 in 2011 to 11.89E+15 sej ha-1 year-1 in 2021, and the leading cause was a decrease in nitrogen fertilizer usage and working hours. The amount of emergy used to grow 1 g of rice stayed the same between 2016 and 2021 (specific emergy: 13.3E+09 sej g-1), but the sustainability of the rice cropping system (emergy sustainability index, ESI) continued to decrease (2011: 0.107, 2016: 0.088, and 2021: 0.086). This study provides quantitative information on the emergy input structure and characteristics of Korean rice cropping systems. The results of this study can be used as a valuable reference in establishing measures to improve the ecological sustainability of the Korean rice cropping system.

본 연구는 전문가 기반형 모델(Habitat Suitability Index)의 한계로 지적되는 주관적 기준, 통계분석의 부재 등과 통계기반형 모델(MaxEnt)의 한계로 지적되는 현장검증, 전문가 의견 반영 등의 극복을 위하여 각각의 모델을 개발하여 통합하는 방식으로 핵심서식지를 도출하였다. 핵심서식지 발굴을 위해 문헌분석 및 공간분석자료를 바탕으로 전문가 심층면담을 진행하였고, 전문가 자문과 GIS 도면 구축 가능성을 고려하여 모델을 개발하였다. 주요 환경변수는 식생대, 임상, 임분밀도, 연평균 강수량, 유효토심으로 선정되었다. 그 결과 현재 나도승마가 분포하고 있는 16지점 중 15지점이 핵심서식지로 나타났으며, 개발된 모델은 약 93.75%의 높은 정확도를 가지고 있는 것으로 나타났다. 하지만 전체 연구대상지의 약 27.8%가 핵심서식지로 나타남에 따라, 추후 서식변수 및 공간자료 정밀화를 통한 모델의 고도화가 필요할 것으로 판단된다. 따라서 높은 등급으로 확인된 서식지라도 대상종의 서식유무 파악을 위한 현장검증은 필수적으로 수행되어야 한다. 하지만, 이러한 한계에도 불구하고 HSI와 MaxEnt의 상호보완적 활용은 생물종의 분포와 서식지 이용 특성을 통하여 적합 서식지를 예측하고, 신규 서식지 발굴 및 대체서식지 선정 등 다양한 방면으로 활용 가능할 것으로 판단된다.

This study was conducted to analyze the effects of stand density on fire fuel (FF) changes in a Chamaecyparis obtusa forest. The study site was located in Mt. Munsu in Jeollabuk-do and consisted of a control, 30% thinning treatment (LT), and 50% thinning treatment (HT). Three-year-old seedlings were planted at a density of 3,000 trees ha-1 in 1976, and thinning was carried out in 2000. FF production was measured every 2 months by installing 3 circular litter traps 1.2 m above the ground. Litter bags containing 5 g of each leaf and branch were made and buried in the organic layer to investigate the FF decomposition rate. The decay constant was calculated after 18 months. FF accumulation was measured by collecting dry-weight organic matter from each plot using a square frame (0.09 m2) in September 2018. The FF production in LT and HT was significantly lower than that of the control (P<0.001). The leaf decay constant for HT was significantly lower than that of the control (P<0.05). The FF accumulation in HT was significantly lower than that of the control (P<0.01), but LT was not significantly different from the control. The results of this study showed that thinning decreased FF production.

본 연구에서는 고투과성 및 높은 염 제거율을 가지는 역삼투막의 성능향상을 위하여 다양한 첨가제 및 계면중합 시 경화 온도 및 시간에 따른 특성평가에 대한 연구가 수행되었다. 첨가제가 없는 막과 첨가제를 첨가한 막의 모폴로지는 모 두 “ridge-and-valley” 구조를 나타내어, 폴리아미드 층이 다공성 지지층 표면에 성공적으로 중합되었음을 확인하였다. 또한 2-Ethyl-1,3-hexanediol (EHD) 첨가함으로써 향상된 친수성과 수투과율 가졌으며, 이는 접촉각 측정을 통해서 확인되었다. 최 종적으로 97.78%와 98.7%의 NaCl 및 MgSO4 제거율과 3.31 L/(m2⋅h⋅bar)의 높은 수투과율을 가진 고투과성 계면중합막을 제조하였다.

This study presents a novel method for addressing the issue of high-concentration contaminants (ammonium, phosphate, antibiotics) in leachate arising from decomposing livestock carcasses. Antibiotics, developed to eliminate microorganisms, often have low biodegradability and can persist in the ecosystem. This research proposes design elements to prevent contamination spread from carcass burial sites. The adsorbents used were low-grade charcoal (an industrial by-product), Alum-based Adsorbent (ABA), and Zeolite, a natural substance. These effectively removed the main leachate contaminants: low-grade charcoal for antibiotics (initial concentration 1.05 mg/L, removal rate 73.4%), ABA for phosphate (initial concentration 2.53 mg/L, removal rate 99.9%), and zeolite for ammonium (initial concentration 38.92 mg/L, removal rate 100.0%). The optimal mix ratio for purifying leachate is 1:1:10 of low-grade charcoal, ABA, and zeolite. The average adsorbent usage per burial site was 1,800 kg, costing KRW 2,000,000 per ton. The cost for the minimum leachate volume (about 12.4 m3) per site is KRW 2,880,000, and for the maximum volume (about 19.7 m3) is KRW 4,620,000. These findings contribute to resolving issues related to livestock carcass burial sites and suggest post-management strategies by advocating for the effective use of adsorbents in leachate purification.

PURPOSES : This study is to evaluate environmental improvement effects of underground road project, as a case study of ‘Seobu’underground expressway project in Korea. METHODS : The environmental improvement effects of underground road construction were classified into tree sector in this study – air quality, noise, and thermal environment. To evaluate these effects, this study collected and divided environment dataset into before, during, and after ‘Seobu’underground expressway construction, and compared the change of values with entire city. In addition, the quantification method of environmental improvement effects was suggested based on the literature review. RESULTS : The result of this study indicates that there exist significant improvement effects of urban environment after the construction of ‘Seobu’underground expressway. Specifically, the concentration of particulate matters (PM10) and daytime/nighttime noise, and land surface temperature (LST) were improved along the expressway. In addition, the overall environmental benefit of ‘Seobu’ underground expressway was estimated to 1.15 billion won per year. CONCLUSIONS : To promote systematic and consistent underground road project, it is required to establish legislative system for evalauting and supporting urban improvement effects.

Currently, there is no definitive regulation for the appropriate frequency of data sampling in water distribution networks, yet it plays a crucial role in the efficient operation of these systems. This study proposes a new methodology for determining the optimal frequency of data acquisition in water distribution networks. Based on the decomposition of signals using harmonic series, this methodology has been validated using actual data from water distribution networks. By analyzing 12 types of data collected from two points, it was demonstrated that utilizing the factors and cumulative periodograms of harmonic series enables similar accuracy at lower data acquisition frequencies compared to the original signals.

폴리에틸렌 글라이콜 다이아크릴레이트 (polyethylene glycol diacrylate, PEGDA) 하이드로젤을 정삼투 (forward osmosis, FO) 분리막의 지지체로 사용하여 고성능의 FO 분리막을 제조하였다. 친수성의 PEGDA를 자외선 조사를 통한 중합 과 그에 따른 상분리를 이용하여 다공성으로 구조화하였고, 매우 높은 친수성을 가진 하이드로젤 지지체를 얻을 수 있었다. 제조된 친수성 PEGDA 지지체 위에 높은 수투과도와 염 선택도를 확보하기 위해서 일반적인 계면중합 방식이 아닌 톨루엔 을 유기 용매로 사용한 계면중합 방식(TIP)으로 선택층을 도입하였다. 제조된 PEGDA 지지체 기반 분리막은 1.0 M NaCl 유 도 용액과 증류수 유입수를 통한 FO 성능 측정에서 상용 HTI 분리막들에 비해서 매우 높은 수투과도와 낮은 염 선택도를 나 타내었다. 본 연구를 통해, 기존의 소수성 지지체를 추가적으로 개질하는 방식이 아닌 새로운 물질과 제조방식을 사용한 FO 지지체의 가능성을 제시하고자 한다.

This study was conducted to investigate the growth characteristics of domestic 'Sulhyang' strawberry (Fragaria × ananassa Duch.) seedlings and to analyze their relationships in order to develop a growth prediction model. Fresh weight, dry weight, and leaf area were measured to validate the newly developed growth model. The relative growth rate (RGR) of ‘Sulhyang’ seedlings’ dry weight was an average of 0.026 g·g-1·d-1, and it increased to 0.066 g·g-1·d-1 on the 49th day after transplanting (DAT). The relationship between DAT and RGR was represented as RGR (dry weight)(g·g- 1·d-1) = 0.0392/(1 + exp(–(DAT – 34.9940)/5.8662)). The crop growth rate (CGR) was an average of 0.060 g·m-2·d-1, and it increased to 0.211 g·m-2·d-1 on the 70th DAT. The relationship between DAT and CGR was calculated as CGR (dry weight)(g·m-2·d-1) = 0.1293/(1 + exp(–(DAT – 49.3917)/6.0928)). The relationship between shoot fresh weight (y) and shoot dry weight (x) per plant showed a linear relationship of y = 4.3189x + 0.7812 (R2 = 0.9976). Fresh weight, dry weight, and leaf area with respect to DAT and cumulative temperature increased exponentially, and sigmoid curve models were developed based on these data. The model with the highest coefficient of determination was found for the relationship between shoot dry weight (y) and cumulative temperature (x), represented as y = 14.2285/(1 + exp(–(x – 1590.1295)/377.8112)) (R2 = 0.9715). The results of this study can be utilized as valuable information for establishing a systematic management system for seedling production using strawberry cutting propagation methods. For the development of a more precise growth prediction model in the future, it is necessary to analyze and apply a wider range of growth indicators and meteorological factors related to strawberry seedlings.