• Journal of Microbiology and Biotechnology
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• 제30권11호
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• pp.1785-1791
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• 2020

In a previous study, the sequential optimization and regulation of environmental parameters using the PhotoBiobox were demonstrated with high-throughput screening tests. In this study, we estimated changes in the biovolume-based composition of a polyculture built in vitro and composed of three algal strains: Chlorella sp., Scenedesmus sp., and Parachlorella sp. We performed this work using the PhotoBiobox under different temperatures (10-36℃) and light intensities (50-700 μmol m^-2 s^-1) in air and in 5% CO₂. In 5% CO₂, Chlorella sp. exhibited better adaptation to high temperatures than in air conditions. Pearson's correlation analysis showed that the composition of Parachlorella sp. was highly related to temperature whereas Chlorella sp. and Scenedesmus sp. showed negative correlations in both air and 5% CO₂. Furthermore, light intensity slightly affected the composition of Scenedesmus sp., whereas no significant effect was observed in other species. Based on these results, it is speculated that temperature is an important factor in influencing changes in algal polyculture community structure (PCS). These results further confirm that the PhotoBiobox is a convenient and available tool for performance of lab-scale experiments on PCS changes. The application of the PhotoBiobox in PCS studies will provide new insight into polyculture-based ecology.

• 한국농공학회논문집
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• 제63권6호
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• pp.39-47
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• 2021

Reduction effect of the spread of odorant and fine dust through windbreak trees can be predicted through numerical analysis. However, there is a disadvantage that a large space and destructive experiments must be carried out each time to calculate the aerodynamic coefficient of the tree. In order to overcome these shortcomings, In this study, we aimed to estimate the aerodynamic coefficient (C₀, C₁, C₂) by using image processing. Thuja occidentalis, which can be used as windbreak were used as the material. The leaf area index was estimated from the leaf area ratio using image processing with leaf weight, and the optical porosity was calculated through image processing of photos taken from the side while removing the leaves step-by-step. Correlation analysis was conducted with the aerodynamic coefficient of Thuja occidentalis calculated from the wind tunnel test and leaf area index and optical porosity calculated from the image analysis. The aerodynamic coefficient showed positive and negative correlations with the leaf area index and optical porosity, respectively. The results showed that the possibility of estimating the aerodynamic coefficient using image processing.

• 운동영양학회지
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• 제25권4호
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• pp.10-16
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• 2021

[Purpose] The purpose of this study was to (i) assess hydration levels in elite male football players during a national team training camp before and during qualifying matches, (ii) evaluate the effect of coaching strategies for hydration based on feedback from hydration monitoring, and (iii) assess possible relationships between hydration status and training load or wellness markers. [Methods] Thirty-one male players (age 27±4 yrs; height 185±6 cm; weight 82.9±6.7 kg; body fat 10.4±2.3%) representing a national team from the Union of European Football Associations (UEFA) participated. The players were studied during three different national team training camps related to the UEFA Nations League tournament. Urine specific gravity (U_SG) was measured to assess hydration status. During all camps, the players were actively coached on improving strategies for hydration and given individual feedback on their test results. The training load was measured using GPS technology, and wellness questionnaires were completed. [Results] U_SG decreased progressively and significantly (p<0.005) during camp 1 and hydration status improved over the three camps, with fewer dehydrated and more well-hydrated players identified during the last part of camp 3. Significantly (p<0.05) higher U_SG values were observed 2 days prior to a match (MD-2) than on match day (MD); consequently, 52% of the players were dehydrated on MD-2 and only 6% on MD. No correlations were observed between hydration status and training load or wellness markers. [Conclusion] Dehydration is a challenge in elite male football, but continuous monitoring of hydration status and coaching on hydration strategies can lead to major improvements and reduce the degree of dehydration.

• Steel and Composite Structures
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• 제48권2호
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• pp.179-190
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• 2023

Many recent attempts have sought accurate prediction of pile pullout resistance (P_ul) using classical machine learning models. This study offers an improved methodology for this objective. Adaptive neuro-fuzzy inference system (ANFIS), as a popular predictor, is trained by a capable metaheuristic strategy, namely equilibrium optimizer (EO) to predict the P_ul. The used data is collected from laboratory investigations in previous literature. First, two optimal configurations of EO-ANFIS are selected after sensitivity analysis. They are next evaluated and compared with classical ANFIS and two neural-based models using well-accepted accuracy indicators. The results of all five models were in good agreement with laboratory P_uls (all correlations > 0.99). However, it was shown that both EO-ANFISs not only outperform neural benchmarks but also enjoy a higher accuracy compared to the classical version. Therefore, utilizing the EO is recommended for optimizing this predictive tool. Furthermore, a comparison between the selected EO-ANFISs, where one employs a larger population, revealed that the model with the population size of 75 is more efficient than 300. In this relation, root mean square error and the optimization time for the EO-ANFIS (75) were 19.6272 and 1715.8 seconds, respectively, while these values were 23.4038 and 9298.7 seconds for EO-ANFIS (300).

• Bulletin of the Korean Chemical Society
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• 제31권5호
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• pp.1199-1203
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• 2010

Second-order rate constants ($k_N$) have been measured spectrophotometrically for Michael-type reactions of 1-(X-substituted phenyl)-2-propyn-1-ones (2a-f) with a series of alicyclic secondary amines in MeCN at $25.0{\pm}0.1^{\circ}C$. The $k_N$ value increases as the incoming amine becomes more basic and the substituent X changes form an electron-donating group (EDG) to an electron-withdrawing group (EWG). The Br${\o}$nsted-type plots are linear with ${\beta}_{nuc}$ = 0.48 - 0.51. The Hammett plots for the reactions of 2a-f exhibit poor correlations but the corresponding Yukawa-Tsuno plots result in much better linear correlations with ${\rho}$ = 1.57 and r = 0.46 for the reactions with piperidine while ${\rho}$ = 1.72 and r = 0.39 for those with morpholine. The amines employed in this study are less reactive in MeCN than in water for reactions with substrates possessing an EDG, although they are ca. 8 pKa units more basic in the aprotic solvent. This indicates that the transition state (TS) is significantly more destabilized than the ground state (GS) in the aprotic solvent. It has been concluded that the reactions proceed through a stepwise mechanism with a partially charged TS, since such TS would be destabilized in the aprotic solvent due to the electronic repulsion between the negative-dipole end of MeCN and the negative charge of the TS. The fact that primary deuterium kinetic effect is absent supports a stepwise mechanism in which proton transfer occurs after the rate-determining step.

• 한국환경과학회지
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• 제26권8호
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• pp.927-938
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• 2017

This study was conducted to determine correlations and similarity between the ozone and $PM_{10}$ data of 19 air quality monitoring stations in Busan from 2013 to 2016, using correlation and cluster analyses. Ozone concentrations ranged from $0.0278{\pm}0.0148ppm$ at Gwangbok to $0.0378{\pm}0.017ppm$ at Taejongdae and were high in suburban areas, such as Yongsuri and Gijang, as well as in coastal areas, such as Jaw, Gwangan, Taejongdae and Noksan. $PM_{10}$ concentrations ranged from $37.2{\pm}25.0ug/m^3$ at Gijang to $58.3{\pm}32.2ug/m^3$ at and Jangrim. $PM_{10}$ concentrations were high in the west, exceeding the annual ambient air quality standard of $50ug/m^3$. Positive correlations were observed for ozone at most stations, ranging from 0.61 between Taejongdae and Sujeong to 0.92 between Bugok and Myeongjang. The correlation coefficients of $PM_{10}$ between stations ranged from 0.62 between Jangrim and Jaw to 0.9 between Gwangbok and Sujeong. Yeonsan, Daeyeon, and Myeongjang were highly correlated with other stations, so they needed to be reviewed for redundancy. Ozone monitoring stations were initially divided into two sections, north-western areas and suburban-coastal areas. The suburban-coastal areas were subsequently divided into three sections. $PM_{10}$ monitoring stations were initially divided into western and remaining areas, and then the remaining areas were subsequently divided into three sections.

• 대한영양사협회학술지
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• 제16권3호
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• pp.195-207
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• 2010

This study aimed to examine factors and the correlations of burnout and job satisfaction in hospital dietitians. Burnout was classified into three sub-concepts: emotional exhaustion, depersonalization, and reduced personal accomplishment. Job satisfaction was also classified into three sub-concepts, including relationships, self-realization, and advancement opportunities. A survey was conducted with dietitians working in general hospitals of over 400 beds, in the Seoul metropolitan area. The factors that significantly influenced emotional exhaustion were health, work hours, number of intern dietitians, self-esteem, level of responsibility, while the factors that influenced depersonalization were relationships with coworkers, and role ambiguity. Personal accomplishment was influenced by age, the number of staff dietitians, the general number of managed workers, and self-esteem. In terms of job satisfaction, relationship was affected by age and relationships with supervisors, while self-realization was influenced by work hours, health, the number of patient meals, and role ambiguity. Age, job regularity, business management, role ambiguity, and relationships with supervisors also affected advancement opportunities. Emotional exhaustion, depersonalization, and reduced personal accomplishments, which represented burnout, had negative relationships with satisfaction with relationships, self-realization and advancement opportunities. Dietitians with low job satisfaction were likely to experience burnout. These results suggest that burnout and job satisfaction are influenced by internal and external factors that are individual or organizational problems encountered by hospital dietitians. Therefore, managers as well as dietitians need to understand these factors and overcome them through communication and mutual support.

• Animal Bioscience
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• 제37권8호
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• pp.1355-1366
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• 2024

Objective: The analysis of runs of homozygosity (ROH) has been applied to assess the level of inbreeding and identify selection signatures in various livestock species. The objectives of this study were to characterize the ROH pattern, estimate the rate of inbreeding, and identify signatures of selection in the red-brown Korean native chickens. Methods: The Illumina 60K single nucleotide polymorphism chip data of 651 chickens was used in the analysis. Runs of homozygosity were analysed using the PLINK v1.9 software. Inbreeding coefficients were estimated using the GCTA software and their correlations were examined. Genomic regions with high levels of ROH were explored to identify selection signatures. Results: A total of 32,176 ROH segments were detected in this study. The majority of the ROH segments were shorter than 4 Mb. The average ROH inbreeding coefficients (F_ROH) varied with the length of ROH segments. The means of inbreeding coefficients calculated from different methods were also variable. The correlations between different inbreeding coefficients were positive and highly variable (r = 0.18-1). Five ROH islands harbouring important quantitative trait loci were identified. Conclusion: This study assessed the level of inbreeding and patterns of homozygosity in Red-brown native Korean chickens. The results of this study suggest that the level of recent inbreeding is low which indicates substantial progress in the conservation of red-brown Korean native chickens. Additionally, Candidate genomic regions associated with important production traits were detected in homozygous regions.

• 한국지반신소재학회논문집
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• 제19권1호
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• pp.103-110
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• 2020

심층혼합공법은 오거를 사용하여 지반을 굴착한 후 지반안정재를 흙 재료와 혼합하여 연약지반에 개량체를 설치하는 공법으로, 지중에 설치되는 개량체는 흙 재료의 종류와 특성에 따라 압축강도가 다르게 발현되기도 한다. 이를 위해 기존의 연구에서는 순환유동층 보일러의 연소재를 고로슬래그의 알칼리 활성화 반응의 자극재로 활용하여 개발한 심층혼합공법용 지반안정재를 부산, 여수, 인천 지역의 점토와 혼합한 후 실내 배합시험을 실시하고, 결과를 분석하여 단위안정재량(γ_B)과 일축압축강도(q_u)의 상관관계를 도출하였다. 본 연구에서는 새만금 지역을 대상으로 채취한 흙 재료에 대해 동일한 실내시험을 실시하여 도출된 상관관계에 대한 비교검토를 실시하였고, 현장에서 수행한 시험시공 결과를 분석하여 현장에서의 안정성을 평가하였다. 연구결과, 실내시험에서는 기존의 연구를 통해 도출된 단위안정재량(γ_B)과 일축압축강도(q_u)의 상관관계를 만족하는 것으로 나타났고, 현장에서의 시험시공 결과는 현장의 기준강도에 비해 높은 일축압축강도를 보여 안정성 측면에서 우수한 것으로 나타났다.

• 자원환경지질
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• 제55권4호
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• pp.389-398
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• 2022

비소 및 중금속으로 오염된 토양 내 함량과 농작물로 전이되는 함량 간의 관련성을 도출하기 위한 연구가 지속적으로 수행되고 있으나 두 함량 간의 낮은 상관성으로 인하여 명확한 결과가 도출되지 못하고 있다. 이 연구에서는 토양 내 비소 전함량과 단일용출 가용성 함량뿐만 아니라 토양의 물리·화학적 특성을 함께 고려하여 백미로 전이되는 비소 함량을 예측하는 통계학적 모델을 만들고자 하였다. 토양 특성 중 pH, 단일용출 가용성 함량, 유기물 함량에 따라 순차적으로 토양을 분류하며 회귀분석을 통한 예측 모델을 도출하였다. 80개의 백미 내 비소 함량과 토양 내 비소 전함량 및 Mehlich 가용성 함량 간의 상관계수는 각각 0.533과 0.493으로 낮았다. 그러나 토양을 pH, Mehlich 가용성 함량에 대한 전함량, 유기물 함량으로 순차적으로 분류하여 모델을 도출한 결과, ① pH가 6.5보다 높은 13개의 토양은 0.963, ② pH가 6.5 이하이고 As_Tot/As_Mehlich 비가 높은 15개의 토양은 0.849, ③ pH가 6.5 이하이고 As_Tot/As_Mehlich 비가 낮으며 8.5% 이하의 유기물을 함유한 30개의 토양은 0.935로 예측력이 크게 증가하였다. 이 연구에서 도출된 토양 분류에 따른 백미 전이 함량 예측 모델은 비소 오염 토양에 대해 신뢰성 있는 백미 재배 기준을 설정하는데 의미있는 방법론을 제안할 수 있을 것이다.