• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2023년도 학술발표회
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• pp.180-180
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• 2023

To improve global risk management, understanding the characteristics and distribution of precipitation is crucial. However, obtaining spatially and temporally resolved climatic data remains challenging due to sparse gauge observations and limited data availability, despite the use of satellite and reanalysis products. To address this challenge, merging available precipitation products has been introduced to generate spatially and temporally reliable data by taking advantage of the strength of the individual products. However, most of the existing studies utilize all the available products without considering the varying performances of each dataset in different regions. Comprehensively considering the relative contributions of each parent dataset is necessary since their contributions may vary significantly and utilizing all the available datasets for data merging may lead to significant data redundancy issues. Hence, for this study, we introduce a site-specific precipitation merging method that utilizes the Quadruple Collocation (QC) approach, which acknowledges the existence of error-cross correlation between the parent datasets, to create a high-resolution global daily precipitation data from 2001-2020. The performance of multiple gridded precipitation products are first evaluated per region to determine the best combination of quadruplets to be utilized in estimating the error variances through the QC approach and computation of merging weights. The merged precipitation is then computed by adding the precipitation from each dataset in the quadruplet multiplied by each respective merging weight. Our results show that our approach holds promise for generating reliable global precipitation data for data-scarce regions lacking spatially and temporally resolved precipitation data.

• 로봇학회논문지
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• 제18권3호
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• pp.346-351
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• 2023

With the release of numerous open driving datasets, the demand for domain adaptation in perception tasks has increased, particularly when transferring knowledge from rich datasets to novel domains. However, it is difficult to solve the change 1) in the sensor domain caused by heterogeneous LiDAR sensors and 2) in the environmental domain caused by different environmental factors. We overcome domain differences in the semi-supervised setting with 3-stage model parameter training. First, we pre-train the model with the source dataset with object scaling based on statistics of the object size. Then we fine-tine the partially frozen model weights with copy-and-paste augmentation. The 3D points in the box labels are copied from one scene and pasted to the other scenes. Finally, we use the knowledge distillation method to update the student network with a moving average from the teacher network along with a self-training method with pseudo labels. Test-Time Augmentation with varying z values is employed to predict the final results. Our method achieved 3rd place in ECCV 2022 workshop on the 3D Perception for Autonomous Driving challenge.

• 한국건설관리학회논문집
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• 제24권6호
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• pp.81-90
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• 2023

Climate change has resulted in increased frequency and intensity of heat waves, which poses a significant threat to the health and safety of construction workers, particularly those engaged in labor-intensive and heat-stress vulnerable working environments. To address this challenge, this study aimed to propose an interpretable machine learning approach for forecasting personal heat strain by considering the cumulative effect of heat exposure as a situational variable, which has not been taken into account in the existing approach. As a result, the proposed model, which incorporated the cumulative working time along with environmental and personal variables, was found to have superior forecast performance and explanatory power. Specifically, the proposed Multi-Layer Perceptron (MLP) model achieved a Mean Absolute Error (MAE) of 0.034 (℃) and an R-squared of 99.3% (0.933). Feature importance analysis revealed that the cumulative working time, as a situational variable, had the most significant impact on personal heat strain. These findings highlight the importance of systematic management of personal heat strain at construction sites by comprehensively considering the cumulative working time as a situational variable as well as environmental and personal variables. This study provided a valuable contribution to the construction industry by offering a reliable and accurate heat strain forecasting model, enhancing the health and safety of construction workers.

• 대한수의학회지
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• 제51권4호
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• pp.281-288
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• 2011

Lactobacillus salivarius JWS 58 (JWS 58) and Lactobacillus plantarum JWS 1354 (JWS 1354) are isolated from duck intestine and have ability to produce bacteriocin. The objective of this study was to evaluate the immunomodulatory effects of JWS 58 and JWS 1354. The nitric oxide (NO) and cytokines (IL-$1{\beta}$ and TNF-${\alpha}$) were measured in C57BL/6 mouse peritoneal macrophages to determine immune enhancing effects of JWS 58 and JWS 1354. A Listeria (L.) monocytogenes challenge mice model was used to evaluate immune enhancement ability of JWS 58 and JWS 1354 in vivo. The results showed that JWS 58 and JWS 1354 increased the production of NO or cytokines by peritoneal macrophages and that oral administration of viable probiotic strains in mice elicited the immuno-modulatory effect upon L. monocytogenes challenge. JWS 1354 showed stronger immune enhancing effects than JWS 58. Collectively, this study demonstrated that Lactobacillus strain JWS 58 and JWS 1354 possess immune enhancing effect. Furthermore, two stains are expected to use feed supplement to prevent diseases by pathogenic bacteria through releasing bacteriocin and enhancing host immune responses in animal.

• Toxicological Research
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• 제34권1호
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• pp.7-12
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• 2018

Laboratory animal models have been developed to investigate preventive or therapeutic effect of medicinal products, or occurrence or progression mechanism of atopic dermatitis (AD), a pruritic and persistent inflammatory skin disease. The murine model with immunologic phenomena resembling human AD was introduced, which demonstrated skewedness toward predominance of type-2 helper T cell reactivity and pathophysiological changes similar as human AD following 2,4-dinitrochlorobenzene (DNCB) sensitization and challenge. Molecular mechanism on the DNCB-mediated AD was further evaluated. Skin tissues were collected from mice treated with DNCB, and each tissue was equally divided into two sections; one for protein and the other for mRNA analysis. Expression of filaggrin, an important protein for keratinocyte integrity, was evaluated through SDS-PAGE. Level of mRNA expression for cytokines was determined through semi-quantitative reverse transcriptase polymerase chain reaction. Expression of filaggrin protein was significantly enhanced in the mice treated with DNCB compared with the vehicle (acetone : olive oil = 4 : 1 mixture) treatment group or the normal group without any treatment. Level of tumor necrosis factor-alpha and interleukin-18 mRNA expression, cytokines involved in activity of type-1 helper T ($T_H1$) cell, was significantly downregulated in the AD group compared with other control groups. These results suggest that suppression of $T_H1$ cell-mediated immune response could be reflected into the skin tissue of mice treated with DNCB for AD induction, and disturbance of keratinocyte integrity might evoke a compensatory mechanism.

• Asian-Australasian Journal of Animal Sciences
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• 제23권7호
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• pp.916-923
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• 2010

We report nutritional physiology and non-specific immune responses of vitamin E in parrot fish for the first time. This study aimed to investigate the essentiality and requirements in diets based on growth performances, non-specific immune responses and a challenge test against Vibrio angullarum. Six casein-gelatin based semi-purified diets were formulated to contain six graded levels of DL-${\alpha}$-tocopheryl acetate (${\alpha}$-TA) at 0, 25, 50, 75, 100 and 500 mg/kg diet (designated as E0, E25, E50, E75, E100 and E500, respectively) and fed to triplicate groups of juvenile parrot fish for 12 weeks. The analyzed dietary concentrations of vitamin E were 0, 38, 53, 87, 119 and 538 mg/kg diet for E0, E25, E50, E75, E100 and E500, respectively. At the end of the feeding trial, growth performance and feed utilization of fish fed the E25 were significantly higher compared to that of fish fed the other diets. Liver ${\alpha}$-tocopherol concentration was significantly increased with an increase in dietary ${\alpha}$-TA in a dose dependent manner. No apparent clinical signs of vitamin E deficiency and mortality were observed in fish fed the basal diet for 12 weeks. Among the immune responses assayed, phagocytic (NBT assay) and myeloperoxidase activities were significantly increased with increment of dietary ${\alpha}$-TA levels. During the challenge test with V. anguillarum, E75, E100, and E500 diets resulted in higher survivals than E0, E25 and E50 diets. The findings of this study suggest that parrot fish require exogenous vitamin E and the optimum dietary level could be approximately 38 mg ${\alpha}$-TA/kg diet for normal growth and physiology. Dietary ${\alpha}$-TA concentration over 500 mg/kg could be required to enhance the nonspecific immune responses and improve the resistance of juvenile parrot fish against V. anguillarum.

• Toxicological Research
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• 제25권3호
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• pp.132-139
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• 2009

The toxicity test of ammonium persulfate was conducted to ensure of its potential toxic effects according to the single-dose acute oral toxicity study (OECD Guideline 423) and 90-day repeated dose sub-chronic oral toxicity study guideline (OECD Guideline 408) for establishing national chemical management system, and matching in the Globally Harmonized Classification System (GHS) category. In acute oral toxicity study, pasty stool, perineal contamination and temporary body weight decrease were observed after dosing 1st and 2nd challenge (300 mg/kg body weight). All test animals were dead within 6 hours after dosing at 3rd challenge (2000 mg/kg body weight). Therefore, the GHS class of test substance is considered class 4. In sub-chronic toxicity study, body weight changes, food consumptions, hematological, biochemical and pathological examination did not show any noticeable and significant differences between the administered (5, 20, 80 mg/kg body weight) and control (vehicle only) group animals. Based on these results, the no observed adverse effect level (NOAEL) is considered above 80 mg/kg body weight.

• Toxicological Research
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• 제18권2호
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• pp.205-213
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• 2002

This study was undertaken to develop a subacute murine model for predicting occurrence of systemic anaphylaxis and to evaluate efficacy of various immunological parameters as the monitoring indices for the occurrence of anaphyalxis. The murine anaphyalxis model was developed through intraperitoneally sensitizing 100 $\mu\textrm{g}$ ovalbumin (OVA) in the presence of 1 mg alum and 300 ng cholera toxin twice a week interval followed by challenging 500 $\mu\textrm{g}$. OVA intravenously. Typical anaphylaxis symptoms were demonstrated at the both BALB/c mice, a strain prone to type-2 response, and C57BL/6 mice. a strain prone to type-1 response. Level of plasma histamine was approximately 50-fold or 30-fold higher in the mice sensitized with OVA than the mice sensitized with alum plus cholera toxin or the saline-treated mice after OVA challenge, respectively. Sensitization and challenge with OVA significantly enhanced plasma leukotriene $B_4$ level but not IgE levels in comparison with the control mice, which indicated the role of leukotriene $B_4$ for progression of anaphyalxis. Furthermore, among mice suffered from anaphylaxis, levels of OVA-specific IgGl were significantly higher in the BALB/c mice than in the C57BL/6 mice, which implied the genetic susceptibility for the induction of systemic anaphylaxis. Conclusively, simultaneous evaluation of histamine, leukotriene $B_4$, and allergen-specific IgG isotype may serve as more efficient monitoring tool for vaccine-related anaphyalxis.

• Toxicological Research
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• 제28권1호
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• pp.1-4
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• 2012

Bee venom (Apis mellifera L., BV) has been used as a cosmetic ingredient for antiaging, anti-inflammatory and antibacterial functions. The aim of this study was to access the skin sensitization of BV, a Buehler test was conducted fifty healthy male Hartley guinea pigs with three groups; Group G1 (BV-sensitization group, 20 animals), group G2 (the positive control-sensitization group, 20 animals), and group G3 (the ethyl alcohol-sensitization group, 10 animals). The exposure on the left flank for induction was repeated three times at intervals of one week. Two weeks after the last induction, the challenge was performed on the right flank. No treatment-related clinical signs or body weight changes were observed during the study period. The average skin reaction evaluated by erythema and edema on the challenge sites and sensitization rate in the BV-sensitization group at 30 hours were 0.0 and 0%, respectively, which are substantially low compared with in positive control group (average skin reaction: 0.55, sensitization rate: 40%) and identical with in vehicle control group, representing a weak sensitizing potential. The average skin reaction and sensitization rate observed at 54 hours were 0.0 and 0% in the BV-sensitization group, respectively, and 0.25 and 20% in the positive control group, respectively. It was concluded that BV classified to Grade I, induced no sensitization when tested in guinea pigs and may provide a developmental basis for a cosmetic ingredient or external application for topical uses.

• 한국동물위생학회지
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• 제44권4호
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• pp.291-297
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• 2021

Severe outbreaks of porcine epidemic diarrhoea virus (PEDV) have continued to re-emerge worldwide. Because of the high mortality rate of suckling piglets in PEDV outbreaks, the disease causes significant economic losses in the pig industry. The limited pre-existing immunity against this virus is thought to cause an explosive increase in infection in pig farms. This study aimed to evaluate the clinical symptoms of PEDV after intentional exposure (feedback). During the first few days of the outbreak in a breeding pig farm, 14 sows showed watery diarrhoea, and the disease subsequently spread rapidly throughout the barn. Pigs that were intentionally exposed to PEDV (n=251) showed watery diarrhoea (46.6%), reduced appetite (17.5%), and vomiting (6.0%). However, 75 exposed pigs (29.9%) showed no clinical signs of disease. Four weeks after the feedback challenge, 34 sows gave birth to litters of piglets, which survived with no diarrhoea. Five weeks after the start of the outbreak, PEDV was not detected in any of the examined samples, including environmental swabs. Thus, early diagnosis, prompt establishment of herd immunity, and strict application of biosecurity are good practices to reduce the mortality rates among new-born piglets and control economic losses in pig farms showing PEDV outbreaks.