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        검색결과 79

        1.
        2024.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        This study develops a model to determine the input rate of the chemical for coagulation and flocculation process (i.e. coagulant) at industrial water treatment plant, based on real-world data. To detect outliers among the collected data, a two-phase algorithm with standardization transformation and Density-Based Spatial Clustering of Applications with Noise (DBSCAN) is applied. In addition, both of the missing data and outliers are revised with linear interpolation. To determine the coagulant rate, various kinds of machine learning models are tested as well as linear regression. Among them, the random forest model with min-max scaled data provides the best performance, whose MSE, MAPE, R2 and CVRMSE are 1.136, 0.111, 0.912, and 18.704, respectively. This study demonstrates the practical applicability of machine learning based chemical input decision model, which can lead to a smart management and response systems for clean and safe water treatment plant.
        4,000원
        2.
        2024.05 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Broccoli and cabbage are known to have antioxidant, cholesterol-lowering, and anticancer effects due to their high bioactive component levels. This study applied 70% ethanol and hydrothermal extraction to separate bioactive components from broccoli and cabbage. 30oBrix extracts were freeze-dried and then diluted in various concentrations with distilled water for analysis. Total polyphenol contents, DPPH radical scavenging activity, ABTS radical scavenging activity, ferric ion reducing antioxidant power, and hydrogen peroxide scavenging activity were analyzed. The diverse antioxidant assays, except DPPH radical scavenging activity, showed that hydrothermal extracts had significantly higher activity than the 70% ethanol extracts (p<0.05). In this study, it suggested that hydrothermal extraction is relatively effective in producing broccoli and cabbage extracts. Moreover, hydrothermal extraction conditions could be low-cost and environmentally friendly.
        4,000원
        3.
        2024.04 KCI 등재 구독 인증기관 무료, 개인회원 유료
        경기도에서 유통중인 포도씨유 50건을 대상으로 잔류농 약 실태를 조사하였다. 50건 중 49건에서 10종의 잔류농 약이 161회 검출되었다. 검출된 농약은 boscalid, cyflufenamid, deltamethrin, difenoconazole, fluxapyroxad, fenpyrazamine, kresoxim-methyl, piperonyl butoxide, tebuconazole, trifloxystrobin 으로 살충제 2종, 살균제 8종이었으며 살균제인 boscalid가 44회, fluxapyroxad가 35회로 가장 빈번하게 검출되었다. 검 출범위는 0.01-1.10 mg/kg으로 모두 포도의 잔류농약 허용 기준 이내로 검출되었다. 검출된 농약의 회수율은 72.6- 129.8%이었으며 검출된 농약의 위해성을 알아보기 위해 %ADI를 산출한 결과 0.0028% 이하로 나타나 포도씨유의 잔류농약으로 인한 위해성은 안전한 수준으로 조사되었다. 그러나 본 연구는 시료의 수가 적고 GC/MS/MS로 분석가 능한 농약만 조사하였기 때문에 보다 신뢰성 있는 결과를 얻기 위해선 앞으로도 꾸준한 추적 조사가 필요할 것으로 사료된다.
        4,000원
        4.
        2024.02 KCI 등재 구독 인증기관 무료, 개인회원 유료
        This study aimed to explore the impact of AI image generators on the affective factors of college-level English learners and the correlations among these factors. During a four-week instructional period, 65 participants were asked to use Midjourney as an AI tool for their user experiences. Affective factors including interest, confidence, and participation were measured through pre- and post-surveys. Using Jamovi for analysis, significant improvements were discovered across all affective factors. Noteworthy improvements occurred in confidence, indicating a favorable impact by AI-generated images on English learning. Additionally, correlation analysis demonstrated significant positive relationships between interest and confidence, as well as confidence and participation. This confirms the interconnected nature of these affective elements in the learning process. The findings suggest that the educational use of image-generating AI tools can beneficially influence English learners’ affective domains. The study calls for further investigation into the pedagogical applications of image AI to foster a more interactive, engaged, and self-assured attitude towards language learning.
        4,600원
        5.
        2023.11 KCI 등재 구독 인증기관 무료, 개인회원 유료
        In this study, we detected the presence of residual pesticides in 341 agricultural products collected from local food outlets in western Gyeonggi Province. Residual pesticides were detected in 105 (30.8%) samples. Six samples exceeded the legal limits for residual pesticides, resulting in a non-compliance rate of 1.8%, which was slightly higher than the average non-compliance rate of 1.4% in the last three years. Among the tested agricultural products, only fruits and vegetables were found to have pesticide residues, with 24 of 34 fruits (a detection rate of 70.6%) and 81 of 277 vegetables (a detection rate of 29.2%) testing positive. In total, 59 types of pesticides, including acetamiprid, which was detected 208 times, were detected and had a detection range of 0.01–2.38 mg/kg. Among the 105 agricultural products containing pesticide residues, a single pesticide was detected in 62 samples (59%) and two or more pesticides were detected in 43 samples (41%). In particular, 14 pesticides were detected in the same sample of peaches; dinotefuran was detected 21 times. Upon examining the toxicity of the detected pesticides, Class III pesticides (moderate toxicity) were detected 44 times (21.2%) and Class IV pesticides (low toxicity) were detected 164 times (78.8%). Class I, II, and III pesticides with fish toxicity were detected 68 (32.7%), 14 (6.7%), and 126 times (60.6%), respectively. Upon examining the exposure to high-frequency pesticide components detected five or more times, the hazard index was found to be ≤2.8%. Accordingly, the hazard of residual pesticides based on dietary intake was deemed insignificant.
        4,000원
        6.
        2023.11 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The status of residual pesticides was investigated in four pepper seed oil samples and 36 pepperflavored oil samples oil distributed on the market from August to December 2022. A total of 179 pesticides were monitored in 40 samples, and 14 pesticides were detected in 39 of the samples, with a detection range of 0.01-2.16 mg/kg. In chili seed oil, 10 pesticides were detected 27 times with a range of 0.11-2.16 mg/kg, and in pepper-flavored oil, 9 pesticides were detected 94 times with a range of 0.01-0.80 mg/kg. The most frequently detected pesticides were tebuconazole, ethion, and difenoconazole, with ethion being detected in large concentrations in products using Chinese raw materials. Ethion, an unregistered pesticide in the Republic of Korea, has not been detected in the Gyeonggi-do area in the past 10 years. It is thought that the detection of ethion can be utilized as an indicator of products made in China. Peppers are a representative agricultural product for which many pesticides are used, and if the pesticides transferred to pepper seeds are not removed, the probability of detecting various types of pesticides in pepper seed oil is very high. Therefore, continuous research is needed to ensure the safety of pepper seed oil.
        4,000원
        7.
        2023.11 KCI 등재 구독 인증기관 무료, 개인회원 유료
        This study aimed to investigate the acrylamide content in frozen food products after cooking. Twenty samples of bread (Group 1) and 30 samples of processed tuberous and corn vegetable products (Group 2) were selected. Acrylamide levels were quantified using liquid chromatography tandem-mass spectrometry (LC-MS/MS). The frozen food samples were heated using the air fryer cooking method according to the product packaging and were compared to ready-to-eat French fries (Group 3). The results showed that the acrylamide content was the highest in group 3, followed by that in group 2 and group 1. The acrylamide content of all the samples was found to be within the domestic recommended standard of 1 mg/kg. However, when the samples that exceeded EU benchmark level (0.5 mg/kg) were selected and cooked using the deep-fat frying method according to the product packaging, one of them showed the acrylamide content of 1.83 mg/kg, which exceeded the domestic recommended standard. The present study highlights the need for continued evaluation and management to reduce acrylamide contents in frozen foods, as increasing domestic exposure to acrylamide is concerning.
        4,000원
        8.
        2023.11 KCI 등재 구독 인증기관 무료, 개인회원 유료
        This study was conducted to determine seafood product quality change in the fresh food cold chain logistics. Salmon was stored in three different simulated refrigerated distribution environments according to door opening time (0, 20, and 60 s) every 10 min before the samples’ qualities were evaluated. The temperature inside the refrigerator generally rose from the bottom to the top, and it was possible to confirm the rapid change in temperature in the order of A, B, and C as the door opening time increased. It was observed that the freshness of salmon decreased as the door opening time increased through the evaluation of various food qualities of salmon, such as its appearance, color, pH, VBN, moisture content, hardness, general bacteria, and E. coli bacteria. It was confirmed that fresh food quality is strongly associated with delivery temperature, while cold-chain delivery vehicles must reduce heat exposure time during delivery.
        4,000원
        10.
        2023.10 KCI 등재 구독 인증기관 무료, 개인회원 유료
        This study initiated research aligned with the body positivity movement, aiming to explore size diversity for groups facing relative size discrimination due to their deviation from average body types. Using KS adult women's apparel dimensions as a reference, jackets were developed for women in their 20s to 30s who belong to the small petite-size (S[P]) category, which is characterized by a height under 155cm (petite) and a bust-circumference from 72cm to less than 82cm (small). Using 3D virtual-fitting, we conducted experiment-pattern production and refinement and subsequent real-fitting evaluations by participants to objectively validate aesthetics and comfort. The study’s findings are as follows: First, utilizing a 3D virtual-fitting program by identifying ‘creases’ and ‘garment pressure points’ in the jacket appearance, experiment patterns were refined and real jackets were produced. This approach addressed challenges in recruiting participants with specific body types and allowed for efficient research in terms of cost and time. Second, through real-fitting evaluations, basic-fit and slim-fit jackets labeled as <79-88-150> were developed for the S(P) size. we presented ‘size spec’ and ‘ease allowance’ for jackets by waist fit. Both fits received positive evaluations with approximately 53.5cm sleeve length, and 11.7cm shoulder length. The ease allowances for the basic-fit jacket were approximately 9.2cm at the bust circumference, 12.8cm at the waist circumference, and 6cm at the hip circumference. Similarly, the slim-fit jacket exhibited ease allowances of about 4.8cm at the bust circumference, 4cm at the waist circumference, and 4cm at the hip circumference, receiving positive evaluations for aesthetics and comfort.
        5,700원
        11.
        2023.08 KCI 등재 구독 인증기관 무료, 개인회원 유료
        A total of 100 commercially available olive oil products were analyzed for 179 pesticide residues using gas chromatography-tandem mass spectrometry (GC/MS/MS). The olive oil samples were mixed with organic solvents, centrifuged and frozen to remove fat, and pesticide residues were analyzed using the “quick, easy, cheap, effective, rugged, and safe” (QuEChERS) method. The determination coefficient (R2) of the analysis method used in this study was ≥0.998. The detection limit of the method ranged 0.004–0.006 mg/kg and its quantitative limit ranged 0.012–0.017 mg/kg. The recovery rate (n=5) measured at the level ranging 0.01–0.02, 0.1, and 0.5 mg/kg ranged 66.8– 119.5%. The relative standard deviation (RSD) was determined to be ≤5.7%, confirming that this method was suitable for the "Guidelines for Standard Procedures for Preparing Food Test Methods". The results showed that a total of 151 pesticides (including difenoconazole, deltamethrin, oxyfluorfen, kresoxim-methyl, phosmet, pyrimethanil, tebuconazole, and trifloxystrobin) were detected in 64 of the 100 olive oil products. The detection range of these pesticide residues was 0.01–0.30 mg/kg. The percentage acceptable daily intake (%ADI) of the pesticides calculated using ADI and estimated daily intake (EDI) was 0.0001–0.1346, indicating that the detected pesticides were present at safe levels. This study provides basic data for securing the safety of olive oil products by monitoring pesticide residues in commercially available oilve oil products. Collectively, the analysis method used in this study can be used as a method to analyze residual pesticides in edible oils.
        4,000원
        13.
        2022.12 구독 인증기관 무료, 개인회원 유료
        본 연구는 연어(Oncorhynchus keta) 치어의 성장, 생존 및 혈액 성상에 미치는 염분 농도의 영 향을 파악하고자 실시되었다. 실험은 염분 농도 0, 10, 20 및 30‰에서 30일간 실시되었으며 3반복으로 진행되었다. 4주 후 생존율은 0, 10 및 20‰ 실험구에서 87.5% 이상이었으나, 30‰ 실험구는 75%로 유의한 감소를 보였다. 증중율(Weight gain), 일간 성장률(specific growth rate), 사료효율(feed efficiency), 일간 사료섭식량(daily feed intake), 일간 단백질섭취율(daily protein intake), 단백질효율(protein efficiency ratio)은 10‰ 실험구에서 가장 높았다. 혈장성분 중 ALT (alanine aminotransferase)는 10, 20 및 30‰ 실험구가 0‰ 실험구에 비해서 유의한 감소를 보였으나, Na+ (sodium)과 Cl- (chloride)는 유의한 증가를 보였다. 또한, 실험기간 중 TP (total protein)과 K+ (potassium)은 변동을 보이지 않았다. 결론적으로 연어 치어(11~33 g)의 성장과 생존에 적합한 최적의 염분 농도는 10‰로 보이나, 혈액 성상의 영향은 향후 추가적인 연구 가 필요한 것으로 판단된다.
        4,000원
        14.
        2022.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        본 연구는 유통 중인 곡류 87건 및 그 가공식품 66건을 대상으로 발암물질인 무기비소의 오염도를 조사하였다. 높 은 분리능과 감도를 가진 HPLC-ICP/MS를 이용하여 무기 비소 As(III), As(V) 및 유기비소 MMA, DMA, AsB, AsC 를 분석했으며, ICP/MS로 총비소를 정량하였다. 모든 곡 류에서 무기비소가 검출되었으며, 곡류의 총비소는 약 70- 85%의 무기비소와 약 10-20%의 DMA로 구성되었다. 곡 류 분석 결과, 담수재배 종인 쌀과 흑미에서 높았고, 밭 재배 잡곡은 오염도가 낮았다. 쌀의 평균 무기비소 농도 는 쌀눈 0.160 mg/kg, 현미 0.135 mg/kg, 백미 0.083 mg/ kg으로 외피에 비소가 많은 것으로 조사되었다. 곡류 가 공식품은 원재료의 종류와 함량에 따라 무기비소 농도가 달랐으며, 현미와 쌀눈 가공 제품에서 검출량이 많았다. 모든 시료는 기준규격을 초과하지 않았지만, 섭취 빈도가 높으므로 식품 안전을 위해 지속적인 모니터링이 필요할 것으로 판단된다.
        4,000원
        15.
        2022.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Many manufacturers applying third party logistics (3PLs) have some challenges to increase their logistics efficiency. This study introduces an effort to estimate the weight of the delivery trucks provided by 3PL providers, which allows the manufacturer to package and load products in trailers in advance to reduce delivery time. The accuracy of the weigh estimation is more important due to the total weight regulation. This study uses not only the data from the company but also many general prediction variables such as weather, oil prices and population of destinations. In addition, operational statistics variables are developed to indicate the availabilities of the trucks in a specific weight category for each 3PL provider. The prediction model using XGBoost regressor and permutation feature importance method provides highly acceptable performance with MAPE of 2.785% and shows the effectiveness of the developed operational statistics variables.
        4,000원
        16.
        2022.02 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Background: Individuals with calf muscle shortening may have decreased dynamic balance. Objects: This study aimed to investigate the effect of mobilization with movement (MWM) and myofascial release (MFR) on kinematic changes in dynamic balance in individuals with calf muscle shortening. Methods: Thirteen participants were randomly assigned to the MWM or the mobilization with movement added myofascial release (MWM-MFR) group. The MWM group received treatment with only MWM, whereas the MWM-MFR group was treated with MWM and MFR. Pre- and post-intervention passive range of motion (PROM), maximum reaching lengths, and modified star excursion balance test (MSEBT) results were compared for all participants. Wilcoxon signed-rank test and Mann-Whitney U test were used for statistical analysis. Results: The results showed significant within-group differences in ankle PROM, but no significant between-group differences. The maximum reaching length in the MWM-MFR group in the posterolateral direction was significantly different before and after the intervention (p = 0.005). This group also showed significantly reduced ankle abduction in MSEBT during the posteromedial direction section 3 (p = 0.007) and posterolateral direction section 5 (p = 0.049) compared with the MWM group. Conclusion: Combined MWM and MFR intervention improves ankle stability in the coronal plane during the posteromedial and posterolateral forward mo
        4,000원
        17.
        2021.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        This study analyzed product conditions in terms of “size system,” “clothing construction depending on fit,” “details,” “colors,” and “prices,” with an emphasis on young contemporary brands for spring/summer 2021, in order to provide basic data for the development of small-sized women’s jackets. Out of 96 domestic and foreign brands, the study analyzed 254 small-sized jacket products from 23 brands that produce size-XS jackets. First, when examining the sizes for women’s jackets, we found that 8 out of the 23 brands offer a size-XXS option. After conducting tree analysis to analyze the factors affecting the production of size-XXS, the study found significant results in the areas of “distinction between domestic and foreign brands” and “product price.” Second, after categorizing small-sized women’s jackets into 3 categories— fit-slim, basic, and straight—the study analyzed clothing construction elements depending on fit. This seasons mainly feature straight-fit’s hip-line length jacket, a 4-panel pattern, and a panel without a waist dart. Third, the study, through the analysis of the colors of small-sized women’s jackets, found a higher frequency of colors in the order of black (23.0%), white (13.3%), and beige tones (10.1%), with additional colors such as sky blue, rose pink, and aquamarine in production, which exhibit the senses of the seasons. Price analysis revealed that small-sized jackets constituted a price range at the mid-to-low end, as in ₩50,000-100,000 (30.3%), ₩100,000- 150,000 (19.3%), and ₩150,000-200,000 (11.8%).
        4,900원
        18.
        2021.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        In this paper, a GAN-based data augmentation method is proposed for topology optimization. In machine learning techniques, a total amount of dataset determines the accuracy and robustness of the trained neural network architectures, especially, supervised learning networks. Because the insufficient data tends to lead to overfitting or underfitting of the architectures, a data augmentation method is need to increase the amount of data for reducing overfitting when training a machine learning model. In this study, the Ganerative Adversarial Network (GAN) is used to augment the topology optimization dataset. The produced dataset has been compared with the original dataset.
        4,000원
        19.
        2021.11 KCI 등재 구독 인증기관 무료, 개인회원 유료
        A newly recorded chaetodontid species, Chaetodon speculum Cuvier, 1831 was collected in July, 2021 from Pohang, Korea. Its body color is yellow with black stripe across the eyes and a large spot occupying one fourth of the upper part of the body. C. speculum is very similar to congeneric species, C. zanzibarensis, but it can be distinguished by the size of the spot, shape of the lateral line, number of longitudinal line scales and geographic distribution. C. speculum is readily identified between post-larval stage and adult stage because of its similar external shape. Molecular analysis based on mitochondrial DNA COI sequences showed our specimen perfectly matched C. speculum. Therefore, we propose the new Korean name, “Heug-jeom-na-bi-go-gi” for C. speculum.
        4,000원
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