본 연구는 산업화 유망 식물인 회화나무의 이차대사산물 대량생산용 캘러스 확보에 필요한 기초조건을 확인하고자 수행하였다. 기내 배양한 회화나무 하배축을 2.0 mg·L-1 NAA + 0.1 mg·L-1 TDZ 배지에서 배양하였을 때 유백색의 부드러운 캘러스가 형성되었고, 캘러스 형성률 100±0.0%, 캘러스 형성에 걸리는 기간 7.1±0.03일, 캘러스 무게 249.8±12.73 mg으로 가장 효과적임을 확인하였다. 또한, 하배축에서 유도한 캘러스는 백색광 조건의 1.0 mg·L-1 IBA + 0.1 mg·L-1 TDZ 처리 배지에서 배양하였을 때 연노란색의 단단한 캘러스가 다량으로 형성되었고, 캘러스 생체중 186±5.4 mg, 면적 40.6±1.6 mm2으로 가장 무겁고, 크기가 우수한 것을 확인하였다. 기내 배양한 캘러스 소재 추출물의 추출수율은 50% 에탄올 추출 시 59%, 물 추출 시 54%로 확인하였고, 추출물 내 유효성분으로 마키아인 함량은 1.68 mg·g-1으로 검출되었다. 본 연구의 결과는 산업화 식물로써 유망있는 수종인 회화나무의 기내 대량증식과 이차대사산물 생산성을 향상할 수 있는 위한 기초자료로 활용할 수 있을 것이다.

생태계서비스란 자연생태계가 인간에게 주는 혜택을 통틀어 일컫는 용어이다. 생태계서비스를 정량화하기 위하여 다양한 모형이 개발되어 적용되고 있다. InVEST는 대표적인 생태계서비스 모형이며 그 중 서식지질 평가가 폭넓게 사용되고 있다. 우리나라에서는 국립공원을 대상으로 서식지질 평가가 실시되고 있다. 서식지질 평가를 위해서는 서식 지질 초기값으로 위협인자에 대한 민감도 평가가 이뤄져야 하는데, 이는 국가 및 적용분야에 따라 판이하다. 그래서 그동안 진행된 국립공원 서식지질 평가를 바탕으로 전문가 설문(AHP)을 실시하여 서식지질 초기값인 민감도의 기준을 조정하였다. AHP실시 결과 자연초지, 경지정리가 안된 밭 등 10개 항목이 상향조정되었으며, 하천, 호소 등 8개 항목이 하향조정되어 총 18개 항목이 조정되었다. 조정된 민감도 결과를 바탕으로 도시형인 북한산국립공원과 계룡산국립공 원, 사적형인 경주국립공원, 해상해안형인 한려해상국립공원 그리고 산악형인 지리산국립공원과 설악산국립공원을 대상지 서식지질 분석을 실시하였다. 분석결과 국립공원내 분포하는 시가화건조지역과 수역에 대한 부분이 서식지질 평가에 반영되었음을 알 수 있었다. 향후 이 기준을 이용하여 자연공원의 서식지질 평가가 가능할 것이다.

In this study, we estimated the distribution density of giant jellyfish in coastal waters of Korea in 2023 and compared the occurrence of giant jellyfish over four years. In May, the giant jellyfish were mainly distributed in the waters of the Yangtze River outflow, and in July, they were highly distributed in the west of Jeju Island and near the south coast of Korea. In addition, when comparing the distribution densities of giant jellyfish in Korea over four years, both acoustic and sighting surveys showed that the highest density of jellyfish occurred in 2021.

코로나19(COVID-19) 상황으로 감염예방과 관리지침에 따라, 정신간호학 실습을 대면으로 진행할 수가 없어, 긴급하게 온라인 실습으로 전환되었다. 이에 본 연구는 간호대학생의 정신간호학 현장실습 대체 온라인 실습에서 성찰일지를 내용분석하여 온라인 실습 교육과정의 질적인 향상을 위한 기초 자료로 활용 하고자 하였다. 연구 참여자는 2021년 정신간호학 온라인 실습에 참여한 간호대학 3학년 학생 31명의 성찰일지를 분석대상으로 하였다. 참여자의 실습이 종료된 2022년 4월 4일부터 5월 31일까지 자료 수집하 였고, 크리펜도르프(Krippendorff, 2019)의 내용분석에 따라 분석하였다. 정신간호학 온라인 실습 성찰일지 를 내용분석한 결과, ‘자기인식의 중요성을 확인함’, ‘정신건강의 가치를 알게 됨’, ‘정신질환자의 회복에 대해 생각함’, ‘치료적 의사소통 향상에 노력함’, ‘정신질환자에 대한 편견이 감소됨’, ‘온라인 실습에 대한 양가감정이 듦’의 6개의 범주로 도출되었다. 본 연구결과를 토대로 정신간호학 온라인 실습에서의 간호대 학생의 성찰의 의미를 파악할 수 있었고, 이러한 성찰일지를 대면 실습 혹은 정신건강전문가 양성과정에도 활용하여 연구하기를 제안한다.

본 연구는 자살생존 배우자의 애도경험을 보다 새롭고 깊이 있게 탐구 하기 위한 목적으로 Aguirre와 Bolton(2014)이 제시한 질적 해석적 메 타통합 방법(Qualitative Interpretive Meta Synthesis, QIMS)을 적용 하였다. 연구의 목적은 1차 질적 문헌연구들을 수집하고 이를 체계적으 로 분석하여 자살생존 배우자들의 애도경험을 이해하고, 이들의 회복과 삶의 재건을 도울 수 있는 새로운 실천방안을 발굴하는 것이다. 이를 위 해 2010년부터 2023년 9월까지 국내에서 수행된 자살생존 배우자 애도 경험에 관한 7편의 질적 논문을 최종분석에 포함하였고, 자살생존 배우 자 34명의 진술을 분석하였다. 자료범위의 축소와 주제 추출 및 통합 과 정을 통해 새롭고 의미 있게 도출된 내용은 39개의 주제범주, 12개의 통 합주제로 결집하였다. 이를 다시 근거이론의 패러다임 모형에 재배열하 여 구조화하였다. 마지막으로 연구결과에 근거하여 자살생존 배우자들의 애도경험을 체계적으로 해석 기술했으며, 자살생존 배우자들의 회복을 돕는 실천방안을 제시했다.

본 연구는 간호대학생의 진로적응력을 증진하기 위한 고려로 낙관성과 진로적응력 간 관계에서 학습몰입의 매개 효과를 파악하고자 수행된 서술적 조사연구이다. 연구대상은 G시와 M시의 4년제 대학 간호학과에 재학 중인 학생이며, 자료는 2023년 4월부터 5월까지 수집하였다. 자료 분석을 위해 기술적 통 계, Pearson 상관계수, Baron과 Kenny의 회귀분석을 실시하였다. 연구결과, 첫째, 낙관성은 학습몰입에 정 적인 영향을 나타냈다. 둘째, 낙관성은 진로적응력에 정적인 영향을 나타냈다. 셋째, 학습몰입은 낙관성과 진로적응력 사이에서 부분 매개효과를 나타냈다. 이로써 간호대학생의 진로적응력을 증진하기 위해서는 낙 관성과 학습몰입을 촉진하기 위한 전략들이 간호교육현장에서 필요함을 알 수 있다.

This study was conducted to investigate whether there were differences in eco-friendly food, home meal replacement (HMR) purchases, and eating-out behavior according to the level of agri-food consumer competence. The data for the study were extracted from main food consumers (n=3,321) in the 2022 Food Consumption Behavior Survey. The competence index was divided into awareness-attitude-practice items, and three groups were classified by competence level. The results showed an agri-food consumer competency score of 70.62, with the highest score for awareness (73.96), followed by practice (69.28) and attitude (66.18). The frequency of purchasing eco-friendly food was higher in the excellent group compared to other groups, and quality and price satisfaction was higher with higher competency (p<0.001). Regarding HMR, the results showed that the shortage group had the lowest HMR consumption rate, and satisfaction decreased as competence decreased (p<0.001). The main reason for eating-out was to enjoy food in all groups (59.0%), followed by a lack of cooking time in the excellent group (15.7%) and hassle with food preparation in the moderate and shortage groups (17.3%, 16.6%) (p<0.001). In short, agri-food consumption competency showed differences by contents and components, and differences in food purchases and eating-out behavior by competency level were found.

This study aimed to develop a solid self-nanoemulsifying drug delivery system (solid-SNEDDS) to enhance the formulation of ketoconazole (KTZ), a BCS Class II drug with poor solubility. Ketoconazole, which is insoluble above pH 3, requires solubilization for effective delivery. This SNEDDS comprises oil, surfactant, and co-surfactant, which spontaneously emulsify in the gastrointestinal tract environment to form nanoemulsions with droplet sizes less than 100 nm. The optimal SNE-vehicle composition of oleic acid, TPGS, and PEG 400 at a 10:80:10 weight ratio was determined based on the smallest droplet size achieved. This composition was used to prepare liquid SNEDDS containing ketoconazole. The droplet size and polydispersity index (PDI) of the resulting liquid SNEDDS were analyzed. Subsequently, solid-SNEDDS was fabricated using a spray-drying method with solidifying carriers such as silicon dioxide, crospovidone, and magnesium alumetasilicate. The physicochemical properties of the solid-SNEDDS were characterized by scanning electron microscopy and powder X-ray diffraction, and its solubility, droplet size, and PDI were evaluated. In particular, the solid-SNEDDS containing ketoconazole and crospovidone in a 2:1 weight ratio exhibited significantly enhanced solubility, highlighting its potential for improved medication adherence and dissolution rates.

Numerous studies have established a correlation between sociodemographic characteristics and water usage, identifying population as a primary independent variable in mid- to long-term demand forecasting. Recent dramatic sociodemographic changes, including urban concentration-rural depopulation, low birth rates-aging population, and the rise in single-person households, are expected to impact water demand and supply patterns. This underscores the necessity for operational and managerial changes in existing water supply systems. While sociodemographic characteristics are regularly surveyed, the conducted surveys use aggregate units that do not align with the actual system. Consequently, many water demand forecasts have been conducted at the administrative district level without adequately considering the water supply system. This study presents an upward water demand forecasting model that accurately reflects real water facilities and consumers. The model comprises three key steps. Firstly, Statistics Korea’s SGIS (Statistical Geological Information System) data was reorganized at the DMA level. Secondly, DMAs were classified using the SOM (Self-Organizing Map) algorithm to consider differences in water facilities and consumer characteristics. Lastly, water demand forecasting employed the PCR (Principal Component Regression) method to address multicollinearity and overfitting issues. The performance evaluation of this model was conducted for DMAs classified as rural areas due to the insufficient number of DMAs. The estimation results indicate that the correlation coefficients exceeded 0.9, and the MAPE remained within approximately 10% for the test dataset. This method is expected to be useful for reorganization plans, such as the expansion and contraction of existing facilities.

Water utilities are making various efforts to reduce water losses from water networks, and an essential part of them is to recognize the moment when a pipe burst occurs during operation quickly. Several physics-based methods and data-driven analysis are applied using real-time flow and pressure data measured through a SCADA system or smart meters, and methodologies based on machining learning are currently widely studied. Water utilities should apply various approaches together to increase pipe burst detection. The most intuitive and explainable water balance method and its procedure were presented in this study, and the applicability and detection performance were evaluated by applying this approach to water supply pipelines. Based on these results, water utilities can establish a mass balance-based pipe burst detection system, give a guideline for installing new flow meters, and set the detection parameters with expected performance. The performance of the water balance analysis method is affected by the water network operation conditions, the characteristics of the installed flow meter, and event data, so there is a limit to the general use of the results in all sites. Therefore, water utilities should accumulate experience by applying the water balance method in more fields.

In this study, the performances of H2S, NH3, and HCl sensors for real-time monitoring in small emission facilities (4, 5 grades in Korea) were evaluated at high concentration conditions of those gases. And the proper approach for the collection of reliable measurement data by sensors was suggested through finding out the effect on sensor performances according to changes in temperature and humidity (relative humidity, RH) settings. In addition, an assessment on sensor data correction considering the effects produced by environmental settings was conducted. The effects were tested in four different conditions of temperature and humidity. The sensor performances (reproducibility, precision, lower detection limit (LDL), and linearity) were good for all three sensors. The intercept (ADC0) values for all three sensors were good for the changes of temperature and humidity conditions. The variation in the slope value of the NH3 sensor showed the highest value, and this was followed by the HCl, H2S sensors. The results of this study can be helpful for data collection by enabling the more reliable and precise measurements of concentrations measured by sensors.

This study aimed to investigate the effect of Liriope platyphylla and organic acids on enteric methane mitigation in goats using an open-circuit simplified respiration chamber system. Methane recovery was evaluated by injecting 3% standard methane gas for 30 min at 3 L/min. The percentage of methane recovery from the four chambers was 99±5.4%. Following the recovery test, an animal experiment was conducted using eight castrated Boer goats (body weight 46.6±7.77 kg) using a 2×2 crossover design. Experimental diets were as follows: 1) Control (CON), commercial concentrate and tall fescue, and 2) Treatment (MIX), concentrate supplemented with L. platyphylla and organic acids and tall fescue. Goats were offered feed at 2% of body weight (dry matter basis) in equal portions twice daily at 8:00 and 15:30. The goats were adapted to the feed and methane chamber for 10 and 3 days, respectively. Methane emission was measured one day per goat using tunable diode laser absorption spectroscopy, and temperature and airflow measurements were used to estimate methane emissions. Dry matter intake (DMI), body weight, and methane emission were measured during each period. Methane production with CON and MIX was 24.48 and 22.68 g/d, respectively, and 26.81 and 24.83 g/kg DMI, respectively. Although the differences were not significant, the use of supplements resulted in a numerical reduction in methane in MIX compared with CON. Collaboration with experts in other areas, including various engineering departments, is imperative to measure methane emissions using a chamber system accurately.

모차르트(Wolfgang Amadeus Mozart, 1756~1791)의 《음악적 농담》(Ein musikalischer Spaβ, K.522)은 1787년에 완성된 디베르티멘토이다. 이 작품에서 모차르트는 일부러 적절하지 못한 작 곡기법들을 사용하고 전통 형식에서 벗어나는 요소들을 통해 음악적인 풍자를 한 것으로 알려져 있다. 모차르트의 의도적인 실수로 보이는 것은 호른의 불협화음, 바이올린의 온음음계, 부속 화 음의 미해결, 병행 5도 진행과 같은 것들을 들 수 있다. 이 작품을 언급하고 있는 연구 논문들은 대부분 이런 표면적인 음악적 풍자에 관해 이야기하고 있지만, 구체적인 분석의 예를 통해서 설명 하는 경우는 찾아보기 힘들다. 본 논문에서는 고전 기악곡들의 형식을 기능과 연관해서 설명하고 있는 캐플린의 이론과 그가 제시한 유형들을 분석 모델로 삼아 모차르트 작품의 제1악장과 제3악 장의 악곡 분석을 통하여 악구 구조와 형식 측면에서 이 작품의 이례적인 점들을 음악적 풍자와 연관 지어 살펴본다.

The EV electric vehicle market is growing rapidly worldwide. Magnet fixing technology is important for mass production of driving motors, a key part of electric vehicles. The magnet fixing method was carried out by the PAM (Polyamide molding) method. This study conducted the injection of rotor core magnet PA of EV traction motor and is a study on the amount of rotor core deformation. In this study, the change in the outer diameter of the product after injection and the non-molding phenomenon were tested. An injection mold was made and the results and phenomena of product deformation types are discussed.

The need for lightweight yet strong materials is being demanded in all industries. Carbon fiber-reinforced plastic is a material with increased strength by attaching carbon fiber to plastic, and is widely used in the aerospace industry, ships, automobiles, and civil engineering based on its low density. Carbon-reinforced fiber plastic is a material widely used in parts and manufactured products, and structural analysis simulation is required during design, and application of actual material properties is necessary for accurate structural analysis simulation. In the case of carbon-reinforced fiber plastics, it is reported that there is a porosity of around 0.5% to 6%, and it is necessary to check the change in material properties according to the porosity and pore shape. It was confirmed by applying the method. It was confirmed that the change in elastic modulus according to the porosity was 10.7% different from the base material when the porosity was 6.0%, and the Poisson's ratio was confirmed to be less than 3.0%. It was confirmed that the elliptical spherical pore derived different material properties from the spherical pore depending on the pore shape, and it was confirmed that the shape of the pore had to be confirmed to derive equivalent material properties.

The effect of the stacking order of carbon fiber composites on impact damage was studied. The main form of damage was delamination starting at the interface between individual ply. The force-time response when the impact was applied was monitored and the energy absorbed by the panel was analyzed. The energy absorbed during interlayer separation was found to be affected by the stacking order, and the residual energy absorbed by peel propagation increased linearly as the total peel area increased. It was found that the compressive strength after impact was related to the maximum delamination area.

High-strength low-alloy steel is one of the widely used materials in onshore and offshore plant engineering. We investigated the alloying effect of solute atoms in α-Fe based alloy using ab initio calculations. Empirical equations were used to establish the effect of alloying on the Vicker’s hardness, screw energy coefficient, and edge dislocation energy coefficient of the steel. Screw and edge energy coefficients were improved by the addition of V and Cr solute atoms. In addition, the addition of trace quantities of V, Cr, and Mn enhanced abrasion resistance. Solute atoms and contents with excellent mechanical properties were selected and their thermal conductivity and thermal expansion behavior were investigated. The addition of Cr atom is expected to form alloys with low thermal conductivity and thermal expansion coefficient. This study provides a better understanding of the state-of-the-art research in low-alloy steel and can be used to guide researchers to explore and develop α-Fe based alloys with improved properties, that can be fabricated in smart and cost-effective manners.

국제적인 선박 배출 가스에 대한 환경 규제가 점차 강화됨에 따라 전기추진 및 하이브리드 추진선박에 대한 관심이 증대되고 있으며, 이러한 선박에 적용하기 위한 다양한 솔루션이 개발 및 적용되고 있는데 특히 전력계통의 안정화, 시스템의 효율성을 높이기 위 한 방안으로 직류배전시스템이 적용되고 있다. 또한, 선박용 직류배전시스템에 대한 안전 및 성능에 대한 검증 및 시험의 중요성이 요구 되고 있다. 본 연구는 직류배전 테스트베드 구축 및 직류배전(가변속 발전)시스템에 대한 성능을 검증하고 연료소모량 분석한 결과로서 선박용 직류배전에 적용되고 있는 가변속 발전시스템을 적용하였으며, 발전기에서 출력되는 전력을 정류기를 통해 직류전력으로 변환하 여 시스템에 연계하고 이러한 장치들을 감시 및 제어하기 위한 시스템을 개발하였다. 이러한 직류배전 시스템을 적용한 시험을 통해 최 대 전압은 751.5V이고 최소전압은 731.4V가 계측되어 전압변동률은 2.7%로 3% 이내에서 안정적으로 전압이 공급되는 것을 확인하였고 부 하변동에 따라 가변속 발전시스템을 적용하였을 경우 연료소모량이 기존 정속발전시스템과 비교하여 구간에 따라 최대 20%이상 연료절 감이 되는 것을 시험을 통해 확인하였다.