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강우자료와 스케일 지수에 대한 경향성 비교 (Comparative a Study on Trend Analysis using Extreme Rainfall Data and Scaling Exponent)

  • 정영훈;김태림;주경원;허준행
    • 한국수자원학회:학술대회논문집
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    • 한국수자원학회 2019년도 학술발표회
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    • pp.339-339
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    • 2019
  • 지구 온난화와 기후변화의 영향으로 태풍의 발생과 집중호우로 인한 홍수피해는 꾸준히 증가하고 있는 실정이다. 이와 같이 홍수와 관련된 강수량은 기상인자 중에서 유역의 유출과 관계가 있고, 유역의 내수침수 등의 도시홍수를 일으키는 원인이 되고 있다. 그러나 본 연구에서는 자료의 경향성을 판단하기 위해 국내 연최대강우자료의 경향성을 분석하였으며, 또한 연최대강우자료의 시간적 특성을 나타내는 지표로써 스케일 지수에 대하여 경향성과 변동성을 분석하였다. 이를 위해 the block bootstrap-based MK (BBS-MK) 분석을 실시하였고, 연최대강우자료로부터 BBS-MK분석에 대한 경향성 분석 결과, 다수 지점의 연최대강우자료에서 경향성이 나타나지 않았으나, 큰 변동성을 확인하였고, 연별 스케일 지수의 변동성 보다 월별 스케일 지수의 변동성 중 우기에 해당하는 월 (6-10월)에 대한 변동성은 크게 나타났다. 스케일 지수의 경향성은 연최대강우자료의 경향성 분석 결과와는 반대로 많은 강우지점에서 경향성이 존재함을 알 수 있었다. 스케일 지수의 경향성 분석 결과, 해안 지역의 강우 관측소에서 감소 경향이 확인되었지만, 내륙 지역에서는 스케일 지수가 증가하는 경향을 확인할 수 있었다.

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Numerical Bayesian updating of prior distributions for concrete strength properties considering conformity control

  • Caspeele, Robby;Taerwe, Luc
    • Advances in concrete construction
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    • 제1권1호
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    • pp.85-102
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    • 2013
  • Prior concrete strength distributions can be updated by using direct information from test results as well as by taking into account indirect information due to conformity control. Due to the filtering effect of conformity control, the distribution of the material property in the accepted inspected lots will have lower fraction defectives in comparison to the distribution of the entire production (before or without inspection). A methodology is presented to quantify this influence in a Bayesian framework based on prior knowledge with respect to the hyperparameters of concrete strength distributions. An algorithm is presented in order to update prior distributions through numerical integration, taking into account the operating characteristic of the applied conformity criteria, calculated based on Monte Carlo simulations. Different examples are given to derive suitable hyperparameters for incoming strength distributions of concrete offered for conformity assessment, using updated available prior information, maximum-likelihood estimators or a bootstrap procedure. Furthermore, the updating procedure based on direct as well as indirect information obtained by conformity assessment is illustrated and used to quantify the filtering effect of conformity criteria on concrete strength distributions in case of a specific set of conformity criteria.

중년기 직장여성의 직무스트레스와 삶의 질의 관계에 대한 갱년기 증상의 매개효과 (Mediation Effect of Menopausal Symptoms between Occupational Stress and Quality of Life among Middle-aged Working Women)

  • 조옥희;임종미
    • 가정∙방문간호학회지
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    • 제28권3호
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    • pp.266-275
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    • 2021
  • Purpose: This study was conducted to explore the mediating effect of menopausal symptoms in the relationship between occupational stress and quality of Life in middle-aged working women Method: Data collection was conducted from May 2019 to July 2019. A sample of 130 middle-aged working women was recruited from three cities in Korea. The collected data were analyzed using descriptive statistics, t-tset, ANOVA, Scheffé test, pearson correlation, and a three step regression analysis. The mediating effect was analyzed using PROCESS macro with a 95.0% bias corrected bootstrap confidence interval (5,000 bootstraps resampling). Results: Quality of life had a negative correlation with occupational stress and menopausal symptoms, while there was a positive correlation between occupational stress and menopausal symptoms. Menopausal symptoms showed a direct effect on quality of life through occupational stress as a mediating variable. Conclusion: These results suggest that menopausal symptoms should be considered when developing interventions to improve quality of life through occupational stress control of middle-aged working women

Endoplura jejuensis sp. nov. and Endoplura koreana sp. nov. (Ralfsiales, Phaeophyceae) from Korea based on molecular and morphological analyses

  • Oteng'o, Antony Otinga;Cho, Tae Oh;Won, Boo Yeon
    • ALGAE
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    • 제36권3호
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    • pp.155-163
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    • 2021
  • The crustose brown algal genus Endoplura has been known as a monotypic genus characterized by its intercalary plurangial reproductive structures composed of 2-4 separate parallel filaments terminated by 2-5 sterile cells and by containing several to many chloroplasts per cell. In this study, Endoplura jejuensis sp. nov. and E. koreana sp. nov. from Korea are newly described based on molecular and morphological analyses. Our phylogenetic analyses of the rbcL gene reveal that E. jejuensis sp. nov. and E. koreana sp. nov. are placed in the same clade with "E. aurea" from Japan with a strong bootstrap supporting value. E. jejuensis is characterized by small and light to dark brown crustose thalli of less than 1 cm diameter, tufts of hairs arising from the basal disc, plurangia composed mostly of two separate parallel reproductive filaments terminated by 2-4 sterile cells, and sessile unangia each with a single paraphysis. E. koreana is distinguished by olive or yellowish-brown crustose thalli of up to 3 cm diameter, tufts of hairs arising from the basal disc, and apical parts of erect filaments, plurangia with 2-5 separate reproductive filaments terminated by 2-8 sterile cells, and sessile unangia with 1-2 paraphyses. Our studies also show that "E. aurea" specimens from Japan may be recognized to be a different species from other Endoplura species.

Critical Factors for Organizational Commitment: An Empirical Study in Vietnam

  • LY, Dan Thanh;LE, Van Chon;BUI, Quang Thong;NGUYEN, Nhu-Ty
    • The Journal of Asian Finance, Economics and Business
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    • 제8권5호
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    • pp.1055-1063
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    • 2021
  • How to manage a business effectively and successfully is the most important goal of all businesses on their way to expand and develop. Most researchers have confirmed that highly committed employees may perform better than less committed ones. The paper aims to find out what critical factors really affect employee's commitment for success of a business. The findings show that three factors having impacts on organizational commitment are leadership, meeting effectiveness and job satisfaction. Particularly, leadership positively affects meeting effectiveness with weight of 0.838. It is believed that if employees feel satisfied with their job, they become more committed to their organization. In addition, it is evident that meeting effectiveness positively affects organizational commitment with weight of 0.296. Last but not the least, in the relationship between meeting effectiveness and organizational commitment, there is a mediator of job satisfaction with the indirect effect of 0.454 and its bootstrap errors at 0.053. It emphasizes the importance of meetings in workplaces. In order to make subordinates satisfied with their jobs, every conflict or problem needs to be thoroughly resolved in meetings. That's why meeting effectiveness has a significant effect on job satisfaction. Furthermore, whether meetings are effective or not is based on leaders or meeting organizers.

Complete mitochondrial genome of Nyctalus aviator and phylogenetic analysis of the family Vespertilionidae

  • Lee, Seon-Mi;Lee, Mu-Yeong;Kim, Sun-sook;Kim, Hee-Jong;Jeon, Hye Sook;An, Junghwa
    • Journal of Species Research
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    • 제8권3호
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    • pp.313-317
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    • 2019
  • Bats influence overall ecosystem health by regulating species diversity and being a major source of zoonotic viruses. Hence, there is a need to elucidate their migration, population structure, and phylogenetic relationship. The complete mitochondrial genome is widely used for studying the genome-level characteristics and phylogenetic relationship of various animals due to its high mutation rate, simple structure, and maternal inheritance. In this study, we determined the complete mitogenome sequence of the bird-like noctule (Nyctalus aviator) by Illumina next-generation sequencing. The sequences obtained were used to reconstruct a phylogenic tree of Vespertilionidae to elucidate the phylogenetic relationship among its members. The mitogenome of N. aviator is 16,863-bp long with a typical vertebrate gene arrangement, consisting of 13 protein-coding genes (PCGs), 22 transfer RNA genes, 2 ribosomal RNA genes, and 1 putative control region. Overall, the nucleotide composition is as follows: 32.3% A, 24.2% C, 14.3% G, and 29.2% T, with a slight AT bias (61.5%). The base composition of the 13 PCGs is as follows: 30.3% A, 13.4% G, 31.0% T, and 25.2% C. The phylogenetic analysis, based on 13 concatenated PCG sequences, infers that N. aviator is closely related to N. noctula with a high bootstrap value (100%).

Genetic Diversity of the Pear Scab Fungus Venturia nashicola in Korea

  • Choi, Eu Ddeum;Kim, Gyoung Hee;Park, Sook-Young;Song, Jang Hoon;Lee, Young Sun;Jung, Jae Sung;Koh, Young Jin
    • Mycobiology
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    • 제47권1호
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    • pp.76-86
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    • 2019
  • Scab disease caused by Venturia nashicola is of agroeconomic importance in cultivation of Asian pear. However, little is known about the degree of genetic diversity in the populations of this pathogen. In this study, we collected 55 isolates from pear scab lesions in 13 major cultivation areas in Korea and examined the diversity using sequences of internal transcribed spacer (ITS) region, ${\beta}$-tubulin (TUB2), and translation elongation factor-$1{\alpha}$ ($TEF-1{\alpha}$) genes as molecular markers. Despite a low level of overall sequence variation, we found three distinctive subgroups from phylogenetic analysis of combined ITS, TUB2, and $TEF-1{\alpha}$ sequences. Among the three subgroups, subgroup 1 (60% of isolates collected) was predominant compared to subgroup 2 (23.6%) or subgroup 3 (16.4%) and was distributed throughout Korea. To understand the genetic diversity among the subgroups, RAPD analysis was performed. The isolates yielded highly diverse amplicon patterns and none of the defined subgroups within the dendrogram were supported by bootstrap values greater than 30%. Moreover, there is no significant correlation between the geographical distribution and the subgroups defined by molecular phylogeny. Our data suggest a low level of genetic diversification among the populations of V. nashicola in Korea.

확률분포를 이용한 남한강 보 건설 전·후 수질변화 분석 (Analysis of Water-Quality Constituents Variations before and after Weir Construction in South Han River using Probability Distribution)

  • 김경섭
    • 한국물환경학회지
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    • 제35권1호
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    • pp.55-63
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    • 2019
  • The Four Major Rivers Restoration Project started in 2009 and completed in early 2013 is a large-scale inter-ministry SOC project investing ₩22.2 $10^{12}$ and one of the Project's objectives was to enhance the water-quality grade through recovering the river eco-system and environment. The average concentration and probability distribution of water-quality constituents at given and selected sampling sites are very significant elements for analyzing and controlling the water-quality of rivers or reservoirs effectively. Average concentration can be estimated by point estimator, distribution function of water-quality constituents or Bootstrap method, in which the distribution function estimated with more data in case of insufficient dataset, is applied. Ipo and Gangcheon water-quality monitoring stations in South Han River were selected to compare and analyze the variation of concentration before and after Ipo and Gangcheon Weirs construction, using the whole 4-year's data, from 2005 to 2008 and from 2014 to 2017. Water-quality constituents such as BOD and COD relating to oxygen demanding wastes and TP and Chlorophyll-a relating to the process of nutrient enrichment called eutrophication were also selected. The guidelines for water-quality control and management after weir construction including evaluation of water-quality constituents' variations can be presented by this paper.

심리적 안정감이 혁신행동에 미치는 영향: 잡 크래프팅(Job Crafting)의 매개효과를 중심으로 (The Effect of Psychological Safety on Innovation Behavior: Focus on Mediating Effect of Job Crafting)

  • 최수형;이정미
    • 아태비즈니스연구
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    • 제11권3호
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    • pp.79-93
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    • 2020
  • Purpose - The purpose of this study analyzes the effect of psychological safety on innovative behavior mediated by job crafting. Design/methodology/approach - This study collected 221 survey data from employees in Korea. Collected data were analyzed using SPSS 25.0 and Macro Process. The multiple regression analysis and bootstrap analysis were hired in order to analyze the data. Findings - First, psychological safety had a significant effect on innovation behavior. Second, job crafting proved a mediating effect in the relationship between psychological safety and innovation behavior. In other words, it has been demonstrated empirically that task crafting, cognitive crafting, and relational crafting, which are sub-elements of job crafting, play a mediating role in the relationship between psychological safety and innovative behavior. Research implications or Originality - This study expanded the study of Job Crafting in that it revealed the mediating role of Job Crafting in the relationship of psychological safety and innovative behavior. Second, this study has novelty in that it has established a sense of psychological safety as an independent variable that promotes innovative behavior, and that it has examined each other's structural relationship by adding a variable called Job Crafting.

기후변화 대응 농업용 저수지의 확률론 기반 홍수 취약성 산정 (Probability Theory-based Flood Vulnerability for Agricultural Reservoirs under Climate Change)

  • 박지훈;강문성;송정헌;전상민
    • 한국수자원학회:학술대회논문집
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    • 한국수자원학회 2017년도 학술발표회
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    • pp.346-346
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    • 2017
  • 기후변화에 따른 기상이변의 동시다발적인 발현은 농촌 지역의 홍수 발생 빈도를 증가시키고 있다. 현재의 기후시스템은 과거의 강우빈도를 기준으로 산정한 설계기준을 벗어나는 강우 사상을 빈번하게 발생시키므로 설계변수의 불확실성을 보다 합리적인 방법으로 정량화할 필요가 있다. 본 연구의 목적은 기후변화에 대응하여 확률론을 이용한 농업용 저수지의 홍수 취약성을 산정하는 데 있다. 먼저 홍수 취약성 해석에 필요한 과거와 미래 수문 자료를 수집하고 전처리 과정을 통해 해석에 적합한 자료로 구축하였다. 설계변수의 불확실성을 분석하기 위해 지속시간별 최대강우량, 유입 설계홍수량에 대해 부트스트랩 (bootstrap) 기법을 적용하여 자료를 재추출하였다. 부트스트 랩은 표본집단의 확률분포에 대해 가정을 하지 않고 표본집단의 통계적 특성을 이용하여 모집단의 통계적 추론을 할 수 있는 비모수적인 리샘플링 기법이다. 부트스트랩 추론은 표본집단의 추정치, 편의, 표준오차를 산정하고 신뢰구간을 추정한다. 부트스트랩 추론을 통해 산정하는 신뢰수준을 이용하여 농업용 저수지의 홍수 취약성을 산정하였다. 본 연구는 설계변수에 내재하는 불확실성을 부트스트랩 기법을 이용하여 정량화하고 확률적인 값을 가지는 홍수 취약성으로 산정하여 제시할 수 있다.

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