세계 해양산업은 자율운항선박 기술의 등장으로 급속도로 발전하고 있으며, 해양 데이터에서 파생된 인공지능 활용에 관한 관 심이 높아지고 있다. 다양한 기술 발전 중에서 선박 항로 군집화는 자율운항선박 상용화를 위한 중요한 기술로 부각되고 있다. 항로 군집 화를 통해 해상에서 선박 항로 패턴을 추출하여 가장 빠르고 안전한 항로를 최적화하고 충돌 방지 시스템의 개발에 기반이 된다. 항로 군 집화 알고리즘의 정확성과 효율성을 보장하기 위해 고품질의 잘 처리된 데이터가 필수적이다. 본 연구에서는 다양한 항로 군집화 방법 중 항로의 실제 형태와 특성을 정확히 반영할 수 있는 선박 항로 유사도 기반 군집화 방식에 주목하였다. 이러한 방식의 효율을 극대화하 기 위해 최적의 데이터 전처리 기술 조합을 구성하고자 한다. 구체적으로, 4가지의 선박 항로 간 유사도 측정법과 3가지의 차원 축소 방 법을 조합하여 연구를 진행하였다. 각 조합에 대해 k-means 군집 분석을 수행하고, 그 결과를 Silhouette Index를 통해 정량적으로 평가하여 최고 성능을 보이는 전처리 기법 조합을 도출하였다. 본 연구는 단순히 최적의 전처리 기법을 찾는 것에 그치지 않고, 광범위한 해양 데 이터에서 의미 있는 정보를 추출하는 과정의 중요성을 강조한다. 이는 4차 산업혁명 시대의 해양 및 해운 산업이 직면한 디지털 전환에 효과적으로 대응하기 위한 기초 연구로서 의의를 갖는다.

In response to the global interest and efforts towards reducing plastic use and promoting resource recycling, there is a growing need to establish methods for recycling discarded fishing gear. In Korea, various technologies are being developed to recycle discarded fishing gear, but significant technical and policy challenges still remain. In particular, biodegradable gill nets require a pre-treatment process to separate biodegradable materials from other substances and to remove salt before recycling. Therefore, this study aims to develop a pre-treatment device for recycling biodegradable gill nets and to evaluate the feasibility of recycling them.

In this study, chemical properties and functional ingredients of ginger and ginger pomace discarded after juice were analyzed. Ginger and ginger pomace were subjected to hot air drying, steaming, followed by hot air drying, soaking in vitamin C for 1 hour and 3 hours. When soaked in vitamin C for 3 hours, the moisture content was highest at 9.2% for ginger and 7.3% for ginger pomace. Among inorganic ingredients, the potassium (K) content was high at 2,633.6 mg% in hot air-dried ginger after steaming and at 1,584.3 mg% in ginger pomace. Total flavonoid content of ginger pomace was high at 67.3 mg/g when soaked in vitamin C for 3 hours. Gingerol content was the highest at 9.8 mg/g when ginger was dried with hot air. It was 10.5 mg/g in ginger pomace. After ginger pomace was steamed and dried with hot air, shogaol content was as high as 2.0 mg/g.

PURPOSES : In this study, a preliminary study on the optimal clustering techniques for the preprocessing of pavement management system (PMS) data was conducted using K-means and mean-shift techniques to improve the correlation between the dependent and independent variables of the pavement performance model. METHODS : The PMS data of Jeju Island was preprocessed using the K-means and mean-shift algorithms. In the case of the K-means method, the elbow method and silhouette score were used to determine the optimal number of clusters (K). Moreover, in the case of the mean-shift method, Scott’s rule of thumb and Silverman’s rule of thumb were used to determine the optimal cluster bandwidth. RESULTS : The optimal cluster sets were selected for the rut depth (RD), annual average daily traffic (AADT), and annual maximum temperature (AMT) for each clustering technique, and their similarities with the original data were investigated. Additionally, the correlation improvement between the dependent and independent variables were investigated by calculating the clustering score (CS). Consequently, the K-means method was selected as the optimal clustering technique for the preprocessing of PMS data. The K-means method improved the correlations of more variables with the dependent variable compared to the mean-shift method. The correlations of the variables related to high temperature—such as the annual temperature change, summer days, and heat wave days—were improved in the case wherein the AMT, a climate factor, was used as an independent variable in the K-means clustering method. CONCLUSIONS : The applicability of the clustering methods to preprocessing of PMS data was identified in this study. Improvements in the pavement performance prediction model developed using traditional statistical methods may be identified by developing a model using clustering techniques in a future study.

PURPOSES : This study aims to provide quantitative profile values for the objective evaluation of concrete surface profile (CSP) grades in concrete structures. The main aims are to quantify the CSP grade required for concrete surface pretreatment and proposing a more suitable CSP grade for structural maintenance. METHODS : Initially, the challenges in measuring concrete surface profiles were outlined by analyzing pretreatment work and profile samples of concrete pavements. Theoretical foundations for quantifying concrete surface roughness were established, and regression models including linear regression, cubic regression, and log regression were selected. Additionally, the interquartile range anomaly removal technique was employed to preprocess the data for regression modeling. RESULTS : Concrete CSP profiles were measured through indoor tests, and the measured data were quantified. Linear regression, cubic regression, and log regression models were applied to each CSP grade for comparative analysis of the results. Furthermore, comparative studies were conducted through adhesion strength tests based on the CSP grade. CONCLUSIONS : Our results are expected to establish objective standards for the pretreatment stage of concrete repair and reinforcement. The derived reference values can inform standards for the restoration and reinforcement of concrete structures, thereby contributing to performance improvement. Moreover, our results may serve as primary data for the repair and reinforcement of various concrete structures such as airports, bridges, highways, and buildings.

This study performed the pre-treatments of the manufacturing of the pork skin snack with wet-salting (3% and 6%; 3W and 6W) and dry-salting (0.3% and 0.6%; 0.3D and 0.6D). Regarding the manufacturing yield, the 0.3D and 6W were significantly higher than the other samples (p<0.05). The water contents of the Con and 0.6D were significantly lower than the other samples (p<0.05). The fat contents of the Con and 6W were evidently higher than the 3W, 0.3D, and 0.6D (p<0.05). The lightness of the wet-salting group was markedly higher than the Con (p<0.05). The redness and yellowness of the 0.6D were noticeably higher than the Con (p<0.05). The crispness of the 0.6D was considerably higher than the other samples (p<0.05). The appearance and sensory crispness of the 3W and 0.6D were notably lower than the other samples (p<0.05). The taste score of the 0.6D was much lower than the 6W and 0.3D (p<0.05). The overall acceptability of the Con, 6W, and 0.3D was appreciably higher than the other samples (p<0.05). Overall, this study showed that wet-salting with 6% (6W) and dry-salting with 0.3% (0.3D) can improve pork skin snack quality properties.

In this study, various pre-treatment methods were evaluated for microalgae separation. These methods aimed to facilitate safe, rapid, and cost-effective online imaging for real-time observation and cell counting. As pre-treatment techniques, heating, chemical hydrolysis, heating combined with chemical hydrolysis, and sonication were employed. The effectiveness of these methods was evaluated in the context of online imaging quality through experimentation on cultivated microalgae (Chlorella vulgaris and Scenedesmus quadricauda). The chemical treatment method was found to be inappropriate for improving image acquisition. The heating pre-treatment method exhibited a drawback of prolonged cell dispersion time. Additionally, the heating combined with chemical hydrolysis method was confirmed to have the lowest dispersion effect for Chlorella vulgaris. Conversely, ultrasonication emerged as a promising technique for microalgae separation in terms of repeatability and reproducibility. This study suggests the potential for selecting optimal pre-treatment methods to effectively operate real-time online monitoring devices, paving the way for future research and applications in microalgae cultivation and imaging.

The objective of this study was to investigate the quality characteristics of Campbell Early grape-added traditional Korean wines (yakju) prepared with different yeasts and pretreatments. The first pretreatment (A) was prepared by crushing the grapes, the second method (B) was prepared by heating the grapes at 60~70℃ for 30 minutes, and the third method (C) was prepared by freeze-concentrating grape juice. The pH of the fermented wines ranged from 3.77 to 4.10, and the total acidity of the samples ranged from 0.32 to 0.62%. The a value (redness) ranged from –0.40 to 17.89, which was higher in Campbell Early-added samples than in the controls (grapes not added). Total polyphenol content was the highest in samples prepared by crushing or heating Campbell Early grapes with ES22, and the total flavonoid contents were the highest in samples prepared by crushing Campbell Early grapes with ES22. The anthocyanin contents were also the highest in the samples fermented by heating Campbell Early grapes. ABTS and DPPH radical scavenging activities were also the highest (84.08 and 77.56%, respectively) in samples fermented by heating Campbell Early grapes.

최근 전기차 및 전력저장 시스템과 같은 대형 전지 시장의 성장으로 인해 리튬 이온 배터리에 대한 수요가 급증하 고 있다. 이에 따라 폐전지의 발생이 빠르게 증가할 것 으로 예상되며, 이에 대한 처리가 사회적 문제가 될 것 으로 예상된다. 폐전지 처리의 가장 효과적인 방법은 폐전지의 소재를 재활용하는 방법이다. 이 중 고가의 금속 물질로서, 재활용 시 경제성이 가장 높은 양극 소재 재활용 연구가 가장 활발히 이뤄지고 있다. 하지만 폐전지로부터 회수된 블 랙 파우더에는 도전재 및 바인더가 포함되어 있는데 양극 소재를 재활용하기 위해서는 이를 제거하는 공정이 필요하 다. 본 연구에서는 폐전지에서 추출된 폐양극 소재의 재활용을 위한 소재 전처리 연구를 제시한다. 열처리 및 화학 처리의 두 가지 전처리 공정을 사용하여 불순물을 제거하였고, 이에 따른 제거 정도를 SEM 분석을 통해 확인하였고, 불순물의 정량 분석을 TGA, EA 분석을 통해 확인하였으며, 전기화학 성능을 분석하였다.

Painting pretreatment is an important task in determining the life of painting as it removes rust or foreign substances from the painting surface and gives adhesion between the painting surface and the painting surface. Since painting pretreatment is an important task, IMO strictly requires that the painting pretreatment surface be maintained at a Sa 2.5 grade and the surface roughness is 30μm~75μm. Painting pre-processing is an important task that determines the lifespan of a painting, but it is done through visual inspection by the inspector, and the quality varies depending on the inspector. In this study, in order to develop a quality measurement system for the painting pretreatment surface, Matlab2023b was used to determine the range of appropriate quality brightness by comparing the brightness of the painting pretreatment surface and surface roughness.

본 연구는 패류 독소 중 기억상실성 독성을 유발하는 domoic acid의 분석법 개선, 검증 및 분석적용성을 살펴보 았다. SAX 카트리지 정제, 검체 및 추출용매 양의 변경 과 더불어 이동상을 용매구매 조건으로 변경시킨 분석법 은 지중해담치, 홍게 그리고 멸치의 세 가지 매트릭스를 대상으로 세 농도에 대하여 식품공전법과 비교하여 유효 성을 검증하였다. 그 결과 변경된 분석법은 LOD 0.02-0.03 mg/kg, LOQ 0.05-0.09 mg/kg, 일내 및 일간 정확도 86.2- 100.4%와 일내 및 일간 정밀도 0.2-4.0%로 CODEX가이 드라인을 만족하는 우수한 분석능을 나타내었다. 특히 변 경된 시험법에서는 domoic acid와 유사한 머무름 시간을 갖는 방해물질이 검출되지 않아 위양성 결과를 방지할 수 있을 것으로 생각된다. 더 나아가 본 분석법이 국내 유통 중인 수산물을 대상으로 적용될 수 있는지 확인하고자 식 품공전의 기억상실성 패독 분석법과 함께 수산물에 적용 하여 분석하였다. 그 결과 5종의 수산물 87건 중 공전시 험법으로 분석했을 때 domoic acid가 검출된 시료는 없었 으나 변경된 분석법을 통하여 멸치 1건에 대하여 0.14 mg/ kg의 domoic acid이 미량 검출되었다. 따라서 본 연구에 서 확립된 분석법은 수산물 중 domoic acid 분석에 활용 이 가능할 것으로 보인다.

Bioreactors are devices used by sewage treatment plants to process sewage and which produce active sludge, and sediments separated by solid-liquid are treated in anaerobic digestion tanks. In anaerobic digestion tanks, the volume of active sludge deposits is reduced and biogas is produced. After dehydrating the digestive sludge generated after anaerobic digestion, anaerobic digested wastewater, which features a high concentration of organic matters, is generated. In this study, the decomposition of organic carbon and nitrogen was studied by advanced oxidation process. Ozone-microbubble flotation process was used for oxidation pretreatment. During ozonation, the TOC decreased by 11.6%. After ozone treatment, the TOC decreased and the removal rate reached 80.4% as a result of the Ultra Violet-Advanced Oxidation Process (UV-AOP). The results with regard to organic substances before and after treatment differed depending on the organic carbon index, such as CODMn, CODCr, and TOC. Those indexes did not change significantly in ozone treatment, but decreased significantly after the UV-AOP process as the linkage treatment, and were removed by up to 39.1%, 15.2%, and 80.4%, respectively. It was confirmed that biodegradability was improved according to the ratio of CODMn to TOC. As for the nitrogen component, the ammonia nitrogen component showed a level of 3.2×102 mg/L or more, and the content was maintained at 80% even after treatment. Since most of the contaminants are removed from the treated water and its transparency is high, this water can be utilized as a resource that contains high concentrations of nitrogen.

Environmental DNA (eDNA) can exist in both intracellular and extracellular forms in natural ecosystems. When targeting harmful cyanobacteria, extracellular eDNA indicates the presence of traces of cyanobacteria, while intracellular eDNA indicates the potential for cyanobacteria to occur. However, identifying the “actual” potential for harmful cyanobacteria to occur is difficult using the existing sediment eDNA analysis method, which uses silica beads and cannot distinguish between these two forms of eDNA. This study analyzes the applicability of a density gradient centrifugation method (Ludox method) that can selectively analyze intracellular eDNA in sediment to overcome the limitations of conventional sediment eDNA analysis. PCR was used to amplify the extracted eDNA based on the two different methods, and the relative amount of gene amplification was compared using electrophoresis and Image J application. While the conventional bead beating method uses sediment as it is to extract eDNA, it is unknown whether the mic gene amplified from eDNA exists in the cyanobacterial cell or only outside of the cell. However, since the Ludox method concentrates the intracellular eDNA of the sediment through filtration and density gradient, only the mic gene present in the cyanobacteria cells could be amplified. Furthermore, the bead beating method can analyze up to 1 g of sediment at a time, whereas the Ludox method can analyze 5 g to 30 g at a time. This gram of sediments makes it possible to search for even a small amount of mic gene that cannot be searched by conventional bead beating method. In this study, the Ludox method secured sufficient intracellular gene concentration and clearly distinguished intracellular and extracellular eDNA, enabling more accurate and detailed potential analysis. By using the Ludox method for environmental RNA expression and next-generation sequencing (NGS) of harmful cyanobacteria in the sediment, it will be possible to analyze the potential more realistically.

The purpose of this study was to confirm the quality characteristics of distilled soju with different rice pretreatment processes. The non-steamed fermentation method is a technology that uses starch to produce saccharification and alcohol without going through the steaming of raw materials. It has advantages such as reduction of manpower and cost, prevention of nutrient loss, and minimization of waste water. In this study, rice used were non-steamed and pulverized 'Baromi2', nonsteamed and steamed ‘Samgwang’, and puffed rice. As the fermenting agent, koji, modified nuruk, N9 yeast, and purified enzyme were used, and lactic acid was added to prevent contamination during fermentation. The amount of water was 300% in total, and after the first watering, 5 days after fermentation, the second watering was carried out. As a result of the study, it was confirmed that the non-steamed fermentation method using ‘Baromi’ was superior to the existing fermentation method in terms of temperature during fermentation, final alcohol content, soluble solids, and pH. By expanding the stability of the production technology of non-steamed fermentation technology, product quality improvement can be expected.