• Title/Summary/Keyword: persistence phenomenon

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The Effect of Students' Confidence of Misconception upon the Conceptual Change in a Conflict Arousing Instruction (인지갈등 유발 수업에서 오개념에 대한 확신도가 개념변화에 미치는 영향)

  • Han, In-Su;Kwon, Nan-Joo;Kwon, Jae-Sool
    • Journal of The Korean Association For Science Education
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    • v.21 no.4
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    • pp.689-696
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    • 2001
  • Students who have correct conception didn't show big changes in a test of cognitive conflict, while students who have misconception made significant changes Most students who had misconception were considerably curious about demonstration of an actual phenomenon. On the other hand, according to their own confidence of preconception, the higher confidence of misconception is, the bigger conflicts are and when they meet some different phenomenon unlike their ideas, their psychological shock was big. After a cognitive conflict lesson, students' conception was significantly changed regardless of students' confidence of preconception and the persistence effect new conceptions showed similar result as preceeding research regardless of confidence of preconception. That is, the change decreased from immediate after demonstration of an conflict situation to a week after. After conceptual change, students' confidence of correct conception was generally increased, so it turned out that cognitive conflict lesson had a positive effect on students who had a misconception.

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Microbial linguistics: perspectives and applications of microbial cell-to-cell communication

  • Mitchell, Robert J.;Lee, Sung-Kuk;Kim, Tae-Sung;Ghim, Cheol-Min
    • BMB Reports
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    • v.44 no.1
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    • pp.1-10
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    • 2011
  • Inter-cellular communication via diffusible small molecules is a defining character not only of multicellular forms of life but also of single-celled organisms. A large number of bacterial genes are regulated by the change of chemical milieu mediated by the local population density of its own species or others. The cell density-dependent "autoinducer" molecules regulate the expression of those genes involved in genetic competence, biofilm formation and persistence, virulence, sporulation, bioluminescence, antibiotic production, and many others. Recent innovations in recombinant DNA technology and micro-/nano-fluidics systems render the genetic circuitry responsible for cell-to-cell communication feasible to and malleable via synthetic biological approaches. Here we review the current understanding of the molecular biology of bacterial intercellular communication and the novel experimental protocols and platforms used to investigate this phenomenon. A particular emphasis is given to the genetic regulatory circuits that provide the standard building blocks which constitute the syntax of the biochemical communication network. Thus, this review gives focus to the engineering principles necessary for rewiring bacterial chemo-communication for various applications, ranging from population-level gene expression control to the study of host-pathogen interactions.

Machine learning techniques for prediction of ultimate strain of FRP-confined concrete

  • Tijani, Ibrahim A.;Lawal, Abiodun I.;Kwon, S.
    • Structural Engineering and Mechanics
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    • v.84 no.1
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    • pp.101-111
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    • 2022
  • It is widely known that axially loaded fiber-reinforced polymer (FRP) confined concrete presents significant and enhanced mechanical properties with reference to the unconfined concrete. Therefore, to predict the mechanical behavior of FRP-confined concrete two quantities-peak strength and ultimate strain are required. Despite the significant advances, the determination of the ultimate strain of FRP-confined concrete is one of the most challenging problems to be resolved. This is often attributed to our persistence in desiring the conventional methods as the sole technique to examine this phenomenon and the complex nature of the ultimate strain of FRP-confined concrete. To bridge the research gap, this study adopted two machine learning (ML) techniques-artificial neural network (ANN) and Gaussian process regression (GPR)-to analyze observations obtained from 627 datasets of FRP-confined concrete circular and non-circular sections under axial loading test. Besides, the techniques are also used to predict the ultimate strain of FRP-confined concrete. Seven parameters namely width/diameter of the specimens, corner radius ratio, the strength of concrete, FRP elastic modulus, FRP thickness, FRP tensile rupture strain, and the axial strain of unconfined concrete-are the input parameters used to predict the ultimate strain of FRP-confined concrete. The results of the current study highlight the merit of using AI techniques in structural engineering applications given their extraordinary ability to comprehend multidimensional phenomena of FRP-confined concrete structures with ease, low computational cost, and high performance over the existing empirical models.

A Study on Market Convergence Dynamics Based on Startup Data: Focusing on Korea (스타트업 데이터 기반의 시장융합 다이내믹스 분석: 한국을 중심으로)

  • Song, Chie Hoon
    • Journal of the Korean Society of Industry Convergence
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    • v.25 no.4_2
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    • pp.627-636
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    • 2022
  • Market convergence plays an increasingly important role in sustaining competitiveness and providing impetus for the new product development. However, existing research focused mostly on the analysis of convergence at technology level. This study examines the phenomenon of market convergence based on the start-up data. Similar to the analysis of technology convergence, this study adopts the concept of co-classification analysis for constructing the co-occurrence matrix and the corresponding network. In this context, network centrality measures were calculated to assess the influence of individual market segments. Based on three metrics "growth", "persistence" and "novelty", the market convergence dynamics were explored and promising interactions between two distinct market segments were highlighted. The findings suggest that both segments "AI" and "blockchain" are acting as a driver that fosters market convergence in the startup landscape. The analysis results can provide valuable information for the R&D managers and policy makers in the design of targeted policies and programs, which can promote market convergence and interdisciplinary knowledge transfer.

Stock Prices and Exchange Rate Nexus in Pakistan: An Empirical Investigation Using MGARCH-DCC Model

  • RASHID, Tabassam;BASHIR, Malik Fahim
    • The Journal of Asian Finance, Economics and Business
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    • v.9 no.5
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    • pp.1-9
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    • 2022
  • The study examines stock prices (LOGKSE) and exchange rate (LOGPK)-Pakistani Rupee vis-à-vis US Dollar- interactions in Pakistan. This study employs a multivariate VAR-GARCH model using monthly data from January 2012 to October 2020. The results of the Johansen cointegration test show that there is no relationship between Foreign Exchange Market and Stock Market in the long run. In the short-run, stock exchange returns are affected slightly negatively by the changes in the foreign exchange market, but the foreign exchange market does not seem to be affected by the ups and downs of the stock exchange. The VAR model and Granger Causality show that both markets are strongly influenced by their own lagged values rather than by the lagged values of one another and show weak or no correlation between the two markets. Volatility persistence is observed in both the stock and foreign exchange markets, implying that shocks and past period volatility are major drivers of future volatility in both markets. Thus greater uncertainties today will induce panic and consequently generate higher volatility in the future period. This phenomenon has been observed many times on Pakistan Stock Exchange especially. The results have important implications for local international investors in portfolio diversification decisions and risk hedging strategies.

A review of experimental and numerical studies on crack growth behaviour in rocks with pre-existing flaws

  • G. Sivakumar;V.B. Maji
    • Geomechanics and Engineering
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    • v.35 no.4
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    • pp.333-366
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    • 2023
  • Rock as a mass generally exhibits discontinuities, commonly witnessed in rock slopes and underground structures like tunnels, rock pillars etc. When these discontinuities experiences loading, a new crack emerges from them which later propagates to a macro scale level of failure. The failure pattern is often influenced by the nature of discontinuity, geometry and loading conditions. The study of crack growth in rocks, namely its initiation and propagation, plays an important role in defining the true strength of rock and corresponding failure patterns. Many researchers have considered the length of the discontinuity to be fully persistent on rock or rock-like specimens by both experimental and numerical methods. However, only during recent decades, there has been a substantial growth in research interest with non-persistent discontinuities where the crack growth and its propagation phenomenon were found to be much more complex than persistent ones. The non-persistence fractures surface is generally considered to be open and closed. Compared to open flaws, there is a difference in crack growth behaviour in closed or narrow flaws due to the effect of surface closure between them. The present paper reviews the literature that has contributed towards studying the crack growth behaviour and its failure characteristics on both open and narrow flaws subjected to uniaxial and biaxial compression loading conditions.

Meteorological drought outlook with satellite precipitation data using Bayesian networks and decision-making model (베이지안 네트워크 및 의사결정 모형을 이용한 위성 강수자료 기반 기상학적 가뭄 전망)

  • Shin, Ji Yae;Kim, Ji-Eun;Lee, Joo-Heon;Kim, Tae-Woong
    • Journal of Korea Water Resources Association
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    • v.52 no.4
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    • pp.279-289
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    • 2019
  • Unlike other natural disasters, drought is a reoccurring and region-wide phenomenon after being triggered by a prolonged precipitation deficiency. Considering that remote sensing products provide consistent temporal and spatial measurements of precipitation, this study developed a remote sensing data-based drought outlook model. The meteorological drought was defined by the Standardized Precipitation Index (SPI) achieved from PERSIANN_CDR, TRMM 3B42 and GPM IMERG images. Bayesian networks were employed in this study to combine the historical drought information and dynamical prediction products in advance of drought outlook. Drought outlook was determined through a decision-making model considering the current drought condition and forecasted condition from the Bayesian networks. Drought outlook condition was classified by four states such as no drought, drought occurrence, drought persistence, and drought removal. The receiver operating characteristics (ROC) curve analysis were employed to measure the relative outlook performance with the dynamical prediction production, Multi-Model Ensemble (MME). The ROC analysis indicated that the proposed outlook model showed better performance than the MME, especially for drought occurrence and persistence of 2- and 3-month outlook.

A Study on the Phenomenal Expression Methods and the Characteristics of Spatial Experience In the Steven Holl's Museum Architecture (스티븐 홀의 뮤지엄 건축에 나타나는 공간체험의 현상적 표현 방법 및 특성에 관한 연구)

  • Jang, Hyun-Ju;Park, Chan-Il
    • Korean Institute of Interior Design Journal
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    • v.25 no.2
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    • pp.151-162
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    • 2016
  • The purpose of this study is to approach to the phenomenological point of view to explore a design method for providing a variety of spatial experience of the viewer according to the functional changes of the modern museum architecture. For that, this study intends to analysis and consider the Steven Holl's Museum applied to the phenomenological perception for architectural design. The method of this study is summarized as follows: 1) Consider the spatial role and function of the Museum Architecture in the phenomenological approach 2) Study on the phenomenological architectural concepts and expressional method of Steven Holl 3) Finally, propose the utilization for the experiential space that is required to implement the contemporary museum architecture. The results of this study are as follows: 1) Steven Holl's phenomenological architectural concept is the basis of the perception and awareness and has connotations of temporality and it is figured out by the approach to the environment, sense and motion. 2) Steven Holl implement the architecture as a place of experience by connecting between the place and the environment through the development of a variety of scenes and situations and planning the phenomenon of multisensory space. 3) The spatial experience appeared in Steven Holl's museum architecture is implemented through the diversity of the scene, the persistence of the situation, the autonomy of light and color, transparency of the haptic and the potential of the material and geometry.

Comparative Evaluation of Standardized Precipitation Index (SPI) and Effective Drought Index (EDI) for Meteorological Drought Detection over Bangladesh (SPI와 EDI 가뭄지수의 방글라데시 기상가뭄 평가 적용성 비교)

  • Kamruzzaman, M.;Cho, Jaepil;Jang, Min-Won;Hwang, Syewoon
    • Journal of The Korean Society of Agricultural Engineers
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    • v.61 no.1
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    • pp.145-159
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    • 2019
  • A good number of drought indices have been introduced and applied in different regions for monitoring drought conditions, but some of those are region-specific and have limitations for use under other climatic conditions because of the inherently complex characteristics of drought phenomenon. Standardized Precipitation Index (SPI) indices are widely used all over the world, including Bangladesh. Although newly developed, studies have demonstrated The Effective Drought Index (EDI) to perform better compared to SPIs in some areas. This research examined the performance of EDI to the SPI for detecting drought events throughout 35 years (1981 to 2015) in Bangladesh. Rainfall data from 27 meteorological stations across Bangladesh were used to calculate the EDI and SPI values. Results suggest that the EDI can detect historical records of actual events better than SPIs. Moreover, EDI is more efficient in assessing both short and long-term droughts than SPIs. Results also indicate that SPI3 and the EDI indices have a better capability of detecting drought events in Bangladesh compared to other SPIs; however, SPI1 produced erroneous estimates. Therefore, EDI is found to be more responsive to drought conditions and can capture the real essence of the drought situation in Bangladesh. Outcomes from this study bear policy implications on mitigation measures to minimize the loss of agricultural production in drought-prone areas. Information on severity level and persistence of drought conditions will be instrumental for resource managers to allocate scarce resources optimally.

Experience of Poverty Exit across Generations (빈곤의 세대간 탈피 경험)

  • Kim, Kyo-seong;Noh, Hye-jin
    • Korean Journal of Social Welfare Studies
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    • v.42 no.1
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    • pp.243-278
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    • 2011
  • The main purpose of this paper is to understand the process of the poverty exit across generations through the live experience based on the grounded theory analysis of the in-depth interview. We find that poverty means a lack of achievement and freedom of agency that is a level of control about resource and situation. So exit of poverty across generations is the state that is not only to achieve functioning but also to recover capabilities. Based on this result, central phenomena of the intergenerational exit process of poverty are support from relation and continuous transition at each stage in life. Even if this central phenomenon is an important event, it has the incomplete attribute. Because support from relation is beyond individual scope of control and participants can't escape second labor market as they don't have enough time in the process of transition. Therefore, this paper suggests that the expansion of state welfare and strategy should support transition as policy priorities to minimize limitation of relation and risk of income loss.