• Title/Summary/Keyword: secondary data analysis

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Characteristics of Long-Term Settlement in the Soft Ground of Nakdong River by Numerical Analysis (수치해석에 의한 낙동강 하구 연약지반의 장기침하특성)

  • Park, Choon-Sik;Ryu, Mean-Young
    • Journal of the Korean Geosynthetics Society
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    • v.18 no.3
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    • pp.55-67
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    • 2019
  • Deep soft ground in mouth of Nackdong river requires to be analysed with prediction method concerning characteristics of secondary consolidation from the beginning because it causes excessive settlement due to time-dependant secondary consolidation characteristics. This study investigated characteristics of extended settlement by conducting one-dimensional theory, elasto-plastic model and visco-elasto-plastic model as well as analyzing long-term measuring data observed over 2,000 days. According to one-dimensional theory and elasto-plastic model, there is not definite correlation between height of embankment and depth of soft ground while visco-elasto-plastic model showed similar result of settlement to that of long-term measuring data. Consequently it is suggested that applying visco-elasto-plastic model to developing deep underground place as studied area on predicting extended settlement before construction prevents economic loss and delay during process by preparing secondary consolidation characteristics.

A Study on Application of Autonomous Traffic Information Based on Artificial Intelligence (인공지능 기반의 자율형 교통정보 응용에 대한 연구)

  • Oh, Am-Suk
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.26 no.6
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    • pp.827-833
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    • 2022
  • This study aims to prevent secondary traffic accidents with high severity by overcoming the limitations of existing traffic information collection systems through analysis of traffic information collection detectors and various algorithms used to detect unexpected situations. In other words, this study is meaningful present that analyzing the 'unexpected situation that causes secondary traffic accidents' and 'Existing traffic information collection system' accordingly presenting a solution that can preemptively prevent secondary traffic accidents, intelligent traffic information collection system that enables accurate information collection on all sections of the road. As a result of the experiment, the reliability of data transmission reached 97% based on 95%, the data transmission speed averaged 209ms based on 1000ms, and the network failover time achieved targets of 50sec based on 120sec.

The tunnel model tests of material development in different surrounding rock grades and the force laws in whole excavation-support processes

  • Jian Zhou;Zhi Ding;Jinkun Huang;Xinan Yang;Mingjie Ma
    • Geomechanics and Engineering
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    • v.36 no.1
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    • pp.51-69
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    • 2024
  • Currently, composite lining mountain tunnels in China are generally classified based on the [BQ] method for the surrounding rock grade. Increasingly, tunnel field construction is replicated indoors for scale down model tests. However, the development of analogous materials for model tests of composite lining tunnels with different surrounding rock grades is still unclear. In this study, typical Class III and V surrounding rock analogous materials and corresponding composite lining support materials were developed. The whole processes of excavation-support dynamics of the mountain tunnels were simulated. Data on the variation of deformations, contact pressures and strains on the surrounding rock were obtained. Finally, a comparative analysis between model tests and numerical simulations was performed to verify the rationality of analogous material development. The following useful conclusions were obtained by analyzing the data from the tests. The main analogous materials of Class III surrounding rock are barite powder, high-strength gypsum and quartz sand with fly ash, quartz sand, anhydrous ethanol and rosin for Class V surrounding rock. Analogous materials for rockbolts, steel arches are replaced by aluminum bar and iron bar respectively with both shotcrete and secondary lining corresponding to gypsum and water. In addition, load release rate of Class V surrounding rock should be less than Class III surrounding rock. The fenestration level had large influence on the load sharing ratio of the secondary lining, with a difference of more than 30%, while the influence of the support time was smaller. The Sharing ratios of secondary lining in Class III surrounding rock do not exceed 12%, while those of Class V surrounding rock exceed 40%. The overall difference between the results of model tests and numerical simulations is small, which verifies the feasibility of similar material development in this study.

Exploring the Perceptions of Secondary Physical Education Teachers According to Changes in the Content System of the 2022 Revised Physical Education Curriculum (2022 개정 체육과 교육과정의 내용 체계 변화에 따른 중등 체육 교사의 인식 탐색)

  • Seung-Yong Kim
    • Journal of Industrial Convergence
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    • v.22 no.8
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    • pp.29-36
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    • 2024
  • The purpose of this study is to provide more effective and realistic basic data to the secondary physical education field by promoting a realistic understanding of the 2022 revised physical education curriculum and providing information on professional development and sustainable policy decisions. The research method was largely an analysis through literature review and qualitative research methods, and data was collected using in-depth interviews. As a result of the study, first, major changes in the content system were confirmed in the 2022 revised physical education curriculum. Second, it was possible to confirm understanding, changes, and improvements regarding the revised curriculum through the perceptions of field physical education teachers. In conclusion, in order for the 2022 revised physical education curriculum to be applied stably, it is believed that it must be accompanied by a systematic approach to teacher education, support for restructuring the curriculum, and improvement in the adaptability of field teachers to the curriculum.

Source Identification and Estimation of Source Apportionment for Ambient PM10 in Seoul, Korea

  • Yi, Seung-Muk;Hwang, InJo
    • Asian Journal of Atmospheric Environment
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    • v.8 no.3
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    • pp.115-125
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    • 2014
  • In this study, particle composition data for $PM_{10}$ samples were collected every 3 days at Seoul, Korea from August 2006 to November 2007, and were analyzed to provide source identification and apportionment. A total of 164 samples were collected and 21 species (15 inorganic species, 4 ionic species, OC, and EC) were analyzed by particle-induced x-ray emission, ion chromatography, and thermal optical transmittance methods. Positive matrix factorization (PMF) was used to develop source profiles and to estimate their mass contributions. The PMF modeling identified nine sources and the average mass was apportioned to secondary nitrate (9.3%), motor vehicle (16.6%), road salt (5.8%), industry (4.9%), airborne soil (17.2 %), aged sea salt (6.2%), field burning (6.0%), secondary sulfate (16.2%), and road dust (17.7%), respectively. The nonparametric regression (NPR) analysis was used to help identify local source in the vicinity of the sampling area. These results suggest the possible strategy to maintain and manage the ambient air quality of Seoul.

Study on the Analysis of Turbulent Flow in a Rotating Square Sectioned $90^{\circ}$ Curved Duct (회전하는 정사각단면 $90^{\circ}$곡관내 난류유동에 관한 수치해석적 연구)

  • 이건휘;최영돈
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.19 no.9
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    • pp.2206-2222
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    • 1995
  • In this study, the characteristics of the three-dimensional turbulence flow in a rotating square sectioned 90.deg. bend were investigated by numerical simulation. And a dimensionless number, Coriolis force ratio, primarily subjected to the feature of the flow in the rotating 90.deg. bend was obtained as a result of one-dimensional theory. In the simulation study, low Reynolds number ASM developed by Kim(1991) in the square sectioned 180.deg. bend flow was modified in order to consider the rotational effects in the testing flows. In the near wall region of low Reynolds number, four turbulence models were employed and compared in order to find the most appropriate model for the analysis of the rotating 90.deg. bend flow. By comparison of the results with the experimental data, it is shown that low Reynolds number Algebraic Stress Model with rotating terms reflects most correctly the rotational effects. As the results of this study, centrifugal forces associated with the curvature of the bend and Coriolis forces and centripetal forces associated with the rotation affect directly both the mean motion and the turbulent fluctuations. Their actions on the mean flow are to induce a secondary motion while their effects on turbulence are to modify the pressure strain.

Taxonomic Reappraisal of Sphacelaria rigidula and S. fusca (Sphacelariales, Phaeophyceae) Based on Morphology and Molecular Data with Special Reference to S. didichotoma

  • Keum, Yeon-Shim;Oak, Jung-Hyun;Draisma, Stefano G.A.;van Reine, Willem F. Prud'homme ;Lee, In-Kyu
    • ALGAE
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    • v.20 no.1
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    • pp.1-13
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    • 2005
  • The taxonomic status of three closely related species of the genus Sphacelaria, S. rigidula Kützing, S. fusca (Hudson) C.F Gray and S. didichotoma Saunders was reassessed on the basis of morphological observations from herbarium specimens and phylogenetic analysis of RUBISCO spacer sequences. Sphacelaria rigidula was characterized by having only 2-armed propagules and somewhat slender filaments. Culture experiments revealed that its propagules commonly formed secondary arms, even though they were rarely produced in the field. It is concluded that S. divaricata Montagne characterized by dichotomously branched arms in propagules shoud be synonymized with S. rigidula, based on propagule morphology and measurements. Sphacelaria fusca clearly be separated from S. rigidula by having 2-4 armed propagules. These morphological differences were highly supported by the differences in the RUBISCO spacer sequences. S. didichotoma resembles S. rigidula in having propagules with two dichotomously branched arms. However, it commonly produces the secondary arms in the field. Additionally, this species has shorter primary arms than S. rigidula. Phylogenetic analyses supported the distinction of S. didichotoma from S. rigidula. The northwestern Pacific plants, previously recorded as S. divaricata, were recognized as S. didichotoma.

In silico analysis of MeJA-induced comparative transcriptomes in Brassica oleraceae L. var. capitata

  • Lee, Ok Ran;Kim, Dae-Soo
    • Journal of Plant Biotechnology
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    • v.43 no.2
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    • pp.189-203
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    • 2016
  • Brassica oleraceae var capitata is a member of the Brassicaceae family and is widely used as an horticultural crop. In the present study, transcriptome analysis of B. oleraceae L. var capitata was done for the first time using eight-week old seedlings treated with $50{\mu}m$ MeJA, versus mock-treated samples. The complete transcripts for both samples were obtained using the GS-FLX sequencer. Overall, we obtained 275,570 and 266,457 reads from seedlings treated with or without $50{\mu}m$ MeJA, respectively. All the obtained reads were annotated using biological databases and functionally classified using gene ontology (GO), the Kyoto Encyclopedia of Genes and Genomics (KEGG). By using GO analyses, putative transcripts were examined in terms of biotic and abiotic stresses, cellular component organization, biogenesis, and secondary metabolic processes. The KEGG pathways for most of the transcripts were involved in carbohydrate metabolism, energy metabolism, and secondary metabolite synthesis. In order to double the sequenced data, we randomly chose two putative genes involved in terpene biosynthetic pathways and studied their transcript patterns under MeJA treatment. This study will provide us a platform to further characterize the genes in B. oleracea var capitata.

Effects of Control Attribution, Demand-Control-Support Model, and Control Strategy on Elderly Workers' Subjective Well-Being (노인 일자리 사업 참여자의 통제 귀인과 활동의 요구-조절-지지 정도 및 통제 전략이 자신의 주관적 안녕감에 미치는 영향)

  • Cho, Yoon-Joo
    • Journal of the Korean Home Economics Association
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    • v.48 no.8
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    • pp.13-26
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    • 2010
  • This study tested the path model with regard to how certain variables (control attribution, demand-control-support of activity, and control strategy) affected the elderly workers' subjective well-being(swb). In the path model, the exogenous variables were internal and external control attribution. We used demand-control-support of activity, and primary and secondary control strategies as mediating variables. The endogenous variable was each elderly worker's swb. Study participants were 205 elders participating in an "education activity". We used descriptive statistical analysis, Pearson's correlation and hierarchical multiple regression to examine data collected from structured interviews with the participants. Path analysis revealed the followings: First, secondary control strategy was the strongest predictor of participants' swb but internal control attribution, demand of activity, and support of activity also positively affected participants' swb. Second, internal control attribution indirectly affected the participants' swb. Finally primary control strategy negatively affected on the participants' swb.

Proteomic Reference Map and Comparative Analysis between Streptomyces griseus S4-7 and wbiE2 Transcription Factor-Mutant Strain

  • Kim, Jisu;Kwon, Young Sang;Bae, Dong-Won;Kwak, Youn-Sig
    • The Plant Pathology Journal
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    • v.36 no.2
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    • pp.185-191
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    • 2020
  • Streptomyces griseus S4-7, a well-characterized keystone taxon among strawberry microbial communities, shows exceptional disease-preventing ability. The whole-genome sequence, functional genes, and bioactive secondary metabolites of the strain have been described in previous studies. However, proteomics studies of not only the S4-7 strain, but also the Streptomyces genus as a whole, remain limited to date. Therefore, in the present study, we created a proteomics reference map for S. griseus S4-7. Additionally, analysis of differentially expressed proteins was performed against a wblE2 mutant, which was deficient in spore chain development and did not express an antifungal activity-regulatory transcription factor. We believe that our data provide a foundation for further in-depth studies of functional keystone taxa of the phytobiome and elucidation of the mechanisms underlying plant-microbe interactions, especially those involving the Streptomyces genus.