This study investigated the quality and antioxidant characteristics of rice morning bread prepared with the addition of apple peel powder (APP, 0, 4, 8, and 12% w/w). It sought to evaluate the influence of APP on the antioxidant capacity of rice morning bread. The findings are summarized as follows: First, as the APP content increased, the weight of the rice morning bread significantly increased, while the volume and specific volume decreased (p<0.001). Second, the Hunter color values showed that the L value (lightness) decreased, whereas the a (redness) and b (yellowness) values increased significantly. Third, texture profile analysis revealed that hardness and chewiness increased with increasing APP levels, whereas cohesiveness decreased (p<0.001). Fourth, antioxidant activities (measured with 2,2-diphenyl-1-picrylhydrazyl [DPPH], 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) [ABTS] radical scavenging ability, and ferric reducing antioxidant power [FRAP]) improved significantly. Fifth, the total phenolic content (TPC) of rice morning bread significantly increased with increasing levels of APP (p<0.05). In conclusion, although APP significantly enhances antioxidant properties, given the bread's physical characteristics, a 4% addition is most appropriate. This study suggests that apple peel powder, a sustainable byproduct, is a promising material for developing functional bakery products.

Aircraft Noise is a sound that humans do not want. In this study, based on the Rotax 914 engine used in Korea, the Propeller blade angle was changed by 1 degree for the 3-leaf “K company” Propeller and the 3-leaf “G” wooden Propeller, and the engine RPM was changed to examine the Noise and thrust changes. The purpose of this study is to check whether Noise and thrust loss are the least at the engine's maximum RPM, and to propose an aircraft operation plan in the noisy aerodrome area based on the values. This research further seeks to identify optimal propeller configurations that balance acoustic performance and thrust efficiency. The results are expected to aid in formulating guidelines for quieter flight operations near populated areas.

This study presents energy-saving performance analysis of a recirculating aquaculture system (RAS) that uses seawater-source heat pumps to control the seawater temperature in the breeding tank. The analysis is based on artificial neural network (ANN) and TRNSYS-based digital twin simulations. The complex thermal load of the RAS, which fluctuates in real time due to changing environmental conditions, is simulated using the dynamic simulation software, TRNSYS. A fuzzy logic controller (FLC) was designed based on the dynamic heat load calculated by TRNSYS and the water temperature data of the breeding tank enabling capacity control of the inverter manipulator of the heat pump. At this stage, energy is saved through the control of the variable speed compressor responding to the partial load via the inverter. Power consumption was predicted at appropriate time intervals using a custom-built ANN model. The prediction results are used to determine the optimal number of heat pumps to operate. Through the digital twin simulation, the proposed heat pump capacity control is compared with conventional operating number control in terms of temperature regulation performance and power consumption. The results demonstrated that the proposed method can be easily implemented in Matlab and significantly improves energy efficiency in RAS farms.

바이오차는 현재 토양개량제이자 탄소격리재로 사용되고 있으며, 건축산업에서 탄소격리에 관한 관심이 증가하고 있다. 본 연구에서는 목질계 바이오차를 시멘트 복합체에 함유하여 탄소격리효과의 가능성을 조사하는 것을 목표로 한다. 목질계 바이오차는 고탄소 물질로 수분을 흡수하는 특성이 있으며 시멘트 복합체에 함유하고자 할 때 시멘트와 비슷한 입도를 가져야한다. 혼입방법에 따라 바이오차를 함유한 시멘트 모르타르의 압축강도 특성을 평가하였으며, 시멘트를 바이오차로 1∼5% 치환하는 경우 Plain 대비 5∼12%까지 압축강도가 증진되는 것을 확인하였다.

도모익산(domoic acid) 군 독소는 기억상실성 패류중독 (amnesic shellfish poison, ASP)을 유발하는 해양생물독소 이다. 도모익산은 주로 규조류 Pseudonitzchia sp. 에서 생 성되어 이매패류의 체내에 축적되어 독화된다. 우리나라 연안에서는 봄철과 가을철에 Pseudonitzchia sp.의 출현이 보고되고 있으며, 수산물 내 도모익산 군 독소의 함량 기 준을 설정하여 관리하고 있다. WHO와 EFSA에서는 선제 적 안전관리를 위하여 인체노출안전기준안을 제안하여 관 리하고 있다. 본 연구는 도모익산 군 독소의 이화학적 특 성, 분석법, 인체 노출 사례와 국내외 관리 현황 등의 자 료를 검토하여 도모익산 군 독소의 체계적인 모니터링과 안전관리의 기반을 마련하고자 수행되었다.

For the OPR1000, a standard power plant in Korea, an analytical model of the containment building considering voids and deterioration was built with multilayer shell elements. Voids were placed in the vulnerable parts of the analysis model, and the deterioration effects of concrete and rebar were reflected in the material model. To check the impact of voids and deterioration on the seismic performance of the containment building, iterative push-over analysis was performed on four cases of the analytical model with and without voids and deterioration. It was found that the effect of voids with a volume ratio of 0.6% on the seismic performance of the containment building was insignificant. The effect of strength reduction and cross-sectional area loss of reinforcement due to deterioration and the impact of strength increase of concrete due to long-term hardening offset each other, resulting in a slight increase in the lateral resistance of the containment building. To determine the limit state that adequately represents the seismic performance of the containment building considering voids and deterioration, the Ogaki shear strength equation, ASCE 43-05 low shear wall allowable lateral displacement ratio, and JEAC 4601 shear strain limit were compared and examined with the analytically derived failure point (ultimate point) in this study.

In response to the global transition towards carbon neutrality, there's an increasing emphasis on sustainable energy solutions, with offshore wind power playing a crucial role, especially in South Korea. This study presents an AI-based safety management system specifically designed for offshore wind operators. At the heart of this system is a machine learning algorithm that processes sensor data to automatically recognize human behavior and improve the accuracy of predicting worker actions and conditions. Such predictive analytics not only refines the analysis of behavioral patterns, but also increases the effectiveness of accident prevention. The results of this research are expected to significantly improve safety measures in offshore wind facilities and further sustainable energy initiatives.

In this study, infrared thermometry techniques were used to conduct surface wetting performance tests (wicking tests) on micropillar structures with good fluid supply capabilities to enhance the critical heat flux. Wicking tests were conducted based on various micropillar shapes (i.e., diameter and spacing) to investigate the surface wetting performance near the boiling point of the fluid(~100°C). The surface temperature was increased from 20°C to 95°C, to examine the wicking performance The shape of the micropillars were quantified by the roughness and the effect of the roughness and temperature on the wicking performance was analyzed. As a result, we confirmed that the roughness of the micropillars increases the capillary pressure, improving the wicking performance. The sample D04 G10 with the highest roughness coefficient at room temperature (r=2.51) exhibited the highest wicking coefficient, showing a 170% improvement in wicking performance compared to D04G20 with the smallest roughness coefficient at room temperature(r=1.51). Additionally, the D04 G10 sample (r=2.51) recorded a 50% improvement in the wicking coefficient at the highest temperature(95°C) compared to room temperature(20°C). The wicking coefficient data will be utilized as a database for developing a new correlation for critical heat flux.

Okadaic acid (OA) group toxins, including OA and its analogs, such as dinophysis toxins (DTXs), have been reported to cause diarrheal shellfish poisoning (DSP). These toxins are primarily produced by dinoflagellates and are accumulated in bivalves. Recently, the presence of Dinophysis sp., a causative alga of DSP, has been reported along the coasts of Korea, posing a potential risk of contamination to domestic seafood and exerting an impact on both the production and consumption of marine products. Accordingly, the European Food Safety Authority (EFSA) and the World Health Organization (WHO) have established standards for the permissible levels of OA group toxins in marine products for safety management. Additionally, in line with international initiatives, the domestic inclusion and regulation of DTX2 among the substances falling under the purview of management outlined by the 2022 diarrheal shellfish toxin standard have been implemented. In this study, we reviewed the physicochemical properties of OA group toxins, their various exposure routes (such as acute toxicity, genotoxicity, reproductive and developmental toxicity), and the relative toxicity factors associated with these toxins. We also performed a comparative assessment of the methods employed for toxin analysis across different countries. Furthermore, we aimed to conduct a broad review of human exposure cases and assess the international guideline for risk management of OA group toxins.

목적: 본 논문의 목적은 연구 문헌 중 요통 환자에게 보행운동을 적용한 무작위 대조군 실험설계를 메타 분석을 하여 통증과 장애지수에 대한 효과를 알아보고자 하였다. 방법: 본 논문은 다음 데이터베이스에서 검색하였다: Google scholar, PubMed, Sciencedirect, KISS, RISS, NDSL. 지난 10년간 영어나 한국어로 된 논문 중, 요통이 있는 환자들이 보행운동을 하였을 때, 통증과 장애지 수를 연구한 논문들을 검색하였다. 이 논문에는 (1) 요통이 있는 환자, (2) 중재에는 보행운동이 포함되며, (3) 평가 지표에는 통증과 장애지수가 포함되었다. 최종 결과로 35개의 논문을 확인하였고, 그중 15개의 논문이 충족되었다. 결과: 본 논문은 요통 환자를 대상으로 보행운동을 중재로 주었을 경우의 논문 15편을 최종적으로 선정하 였고 분석하였다. 통증과 장애지수와 관련되어 각각 12개의 논문을 분석하였다. 통증과 관련된 12개의 논문의 효과 크기는 중간의 효과 크기나 나타났고, 장애지수와 관련된 12개의 논문의 작은 효과 크기가 있었다. 결론: 보행운동은 요통 환자들의 통증을 감소시키고 장애지수를 줄이는데 유의미한 효과가 있다. 따라서 보 행운동은 요통을 지닌 사람들에게 긍정적인 영향을 미칠 것으로 사료된다.

본 연구에서는 용제를 전혀 사용하지않고 UV경화가 가능한 나노 실버 페이스트를 개발하였다. 무용제(solvent-free) 타입으로 개발한 나노 실버 페이스트의 점도 및 점탄성 측정하였다. 그리고 스크린인쇄로 패턴을 인쇄한 후에 UV 경화로 전극도막을 형성시켰다. 형성된 전극도막의 전도성, 연필경도, 접착력에 대해서 평가하였다. 또한 전극 도막 을 광 소결하여 전도성을 평가하였다. 마지막으로 전극도막의 경화특성은 TGA 및 FT-IR로 평가하였다. 이러한 결 과를 정리하면 UV경화만 시켰을 경우에는 전도성, 접착력, 경화특성에 대해서는 Paste(3)이 가장 우수하였다. 그러 나 광소결 후에는 Paste(1)이 가장 우수한 전도성을 얻을수있었다. 그 이유는 10nm 실버 파우더를 사용한 것이 소 결 특성이 가장 우수했기 때문이라고 판단된다.

본 연구에서는 실버 파우더의 입자 크기, 즉 평균 입자 크기가 2㎛과 7㎛, 이렇게 2가지 실버 페이스트를 개발하였다. 이렇게 개 발된 실버 페이스트에 대해서 점도 및 점탄성, 경화후에 잔류용제 유무 확인을 위한 TGA측정, Strain에 따른 저항 변화 및 전극 표면 구조 변화에 대해서 검토하였다. 이러한 결과를 정리하면 Strain에 따른 저항 변화를 최소화하기 위해서는 실버 파우더의 입 자를 2㎛정도인 것이 가장 바람직함을 알 수 있었다.

In order to determine fragility curves, the limit state of piers for each damage level is suggested in this paper based on the previous test results in Korea, including our test results. In previous studies, the quantitative measures for damage levels of piers have been represented by curvature ductility, lateral drift ratio, or displacement ductility. These measures are transformed to lateral drift ratios of piers for consistency, and the transformed values are compared and verified with our push-over test results for flexural RC piers with a circular cross-section. The test specimens are categorized concerning the number of lap-splices in the plastic hinge region and whether seismic design codes are satisfied or not. Based on the collected test results in Korea, including ours, the lateral drift ratio for each pier damage level is suggested.

In this study, numerical analysis is conducted to investigate the flow characteristics of a turning type flood gate fishway with various design factors. The shapes of the fishway are circular and rectangular type. Baffles are installed to reduce the velocity in the fishway, and the gap and rotational arrangement of the baffles are set as design factors. To reduce the maximum velocity, a cavity-shaped break region is installed to examine the flow characteristics according to the presence of the break region. As a result, in the condition where the shape of the fishway is rectangular, the outlet average flow velocity is larger than that in the circular condition. The highest flow velocity occurs when the baffle is rotated in 90-degree arrangement. As the baffle gap increases, the average velocity increases. The cavity-shaped break region creates a recirculation zone in the fishway, and as a result, shows a decrease in the maximum velocity of up to 5.8%.

Various kinds of friction materials were manufactured by adding 10%, 20%, and 30% of reduced iron, respectively, which has been obtained during the reduction process of blast furnace sludge extracted from the blast furnace, and its iron oxide, instead of existing barium sulfate(BaSO4) among the components of automobile brake friction materials. Fundamental physical property test and friction performance test, etc., using a brake dynamometer were carried out against these friction materials. Furthermore, when the expensive filling material, BaSO4 was substituted by reduced iron and added to the friction material, the added content of reduced iron for an excellent friction characteristic considering the heat emission temperature, wear, etc., was 10%. In the fundamental physical property test, as the added content of blast furnace sludge or reduced iron increased, and as the content increased, the shear strength and bonding strength of friction materials decreased, but both of them indicated sufficient strengths to be applied to a friction material. Even in the frictional performance test using a brake dynamometer, as the added content of blast furnace sludge or reduced iron increased, the friction coefficient reacted insensibly to brake deceleration, and its stability was improved.