• 한국과학교육학회지
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• 제21권4호
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• pp.689-696
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• 2001

학생들은 나름대로 자연 현상에 대하여 자신의 인지구조를 가지고 이해하고 있으나 개념에 대한 확신정도는 학생에 따라 다르다. 자신이 갖고 있는 개념에 대하여 뚜렷한 자신감이 있는 학생이 있는가 하면 자신의 개념에 대하여 확신을 못하는 경우가 있다. 이 연구에서는 오개념에 대한 확신도가 높고 낮음에 따라 갈등 효과는 어떠하며, 사후 개념변화는 어떠한지를 알아보고자 하였다. 대부분의 오개념을 가졌던 학생들은 현상 제시에 많은 호기심을 보였으며, 오개념의 확신도가 클수록 갈등을 더 많이 느껴 자신의 생각과 다른 현상을 보았을 때 심리적 충격이 더 크게 변하는 것으로 나타냈다. 그러나 일부 개념에서는 갈등을 많이 겪었다고 응답하였지만 개념변화가 되지 않는 학생들의 비율이 높아 오개념의 견고함을 보여주기도 하였다. 인지 갈등 수업 후 개념의 변화는 선개념에 대한 확신도에 관계없이 잘 일어났으며, 개념변화 지속 효과 또한 확신도에 관계없이 선행 연구자들의 결과와 비슷하게 나왔다. 즉, 현상 제시 직후부터 일주일 후 까지는 감소하나 그 뒤로는 개념이 자리잡았다. 개념 변화 후 바른 개념에 대한 확신도는 대체로 높아서 오개념을 가진 학생에게 과학개념을 심어주기 위한 방편으로 인지갈등 수업이 효과 있음을 보여주었다.

• BMB Reports
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• 제44권1호
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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.

• Structural Engineering and Mechanics
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• 제84권1호
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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.

• 한국산업융합학회 논문집
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• 제25권4_2호
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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.

• The Journal of Asian Finance, Economics and Business
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• 제9권5호
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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.

• Geomechanics and Engineering
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• 제35권4호
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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.

• 한국수자원학회논문집
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• 제52권4호
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• pp.279-289
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• 2019

가뭄재해는 다른 재해와 다르게 광범위한 공간에 걸쳐서 충분한 강우가 발생하기 전까지 오랜 기간 동안 발생되는 특성이 있다. 위성 영상은 시공간적으로 지속적인 강수량 관측을 제공할 수 있다. 본 연구는 위성 영상 기반의 강수자료를 활용하여 기상학적 가뭄 전망 모형을 개발하였다. PERSIANN_CDR, TRMM 3B42와 GPM IMERG 영상을 활용하여 강수 자료를 구축한 뒤, 표준강수지수(SPI)를 기반으로 기상학적 가뭄을 정의하였다. 과거의 가뭄 정보와 물리적 예측 모형 기반의 가뭄 예측 결과를 결합할 수 있는 베이지안 네트워크 기반 가뭄 예측 기법을 이용하여 확률론적 가뭄 예측 결과를 생산하였으며, 가뭄 예측결과를 가뭄 전망 의사결정 모형에 적용하여 가뭄 전망 결과를 도출하였다. 가뭄 전망 정보는 가뭄 발생, 지속, 종결, 가뭄 없음의 4단계로 구분하였다. 본 연구의 가뭄 전망 결과는 ROC 분석을 통하여 물리적 예측 모형인 다중모형 앙상블(MME)을 활용한 가뭄 전망 결과와 전망 성능을 비교하였다. 그 결과, 2~3개월 가뭄 전망에 대한 가뭄 발생 및 지속의 단계에서는 MME 모형보다 높은 전망성능을 보여주었다.

• 한국실내디자인학회논문집
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• 제25권2호
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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.

• 한국농공학회논문집
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• 제61권1호
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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.

• 사회복지연구
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• 제42권1호
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• pp.243-278
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• 2011

본 연구에서는 센의 실현가능능력 접근을 활용하여 보다 확대된 개념으로 빈곤을 조망하면서, 빈곤의 세대간 탈피에 관한 삶의 경험을 이해하고자 한다. 이를 위하여 생애초기 빈곤을 경험했으나 현재 이를 탈피한 자녀세대와 부모세대 참여자와의 심층 면접을 실시하였고, 빈곤의 세대간 탈피과정에서 발생하는 경험과 상호작용을 보다 심도있게 파악하고자 근거이론을 활용하였다. 분석결과 '빈곤' 의 의미는 자원 및 상황에 대하여 개인이 통제를 발휘하는 주체성의 성취와 자유가 부족한 상태임을 확인할 수 있었다. 따라서 빈곤의 탈피는 기능의 성취뿐만 아니라 실현가능능력을 회복한 상태라고 볼 수 있다. 이에 기초하여 세대간 탈피과정을 살펴본 결과, 관계로부터의 도움과 생애주기에서 단계별 이행이 연속적이었다는 것이 중심 현상으로 등장하였다. 이러한 중심현상은 빈곤의 탈피에서 중요한 사건이지만 동시에 불완전한 속성을 가지고 있다. 왜냐하면 관계로부터의 도움은 개인의 통제범위를 일정부분 벗어난 것이고, 참여자들이 이행의 과정에서 충분한 기간을 가지지 못해 2차 노동 시장에서 벗어나지 못하고 있기 때문이다. 따라서 본 연구에서는 관계로부터의 도움이 가지는 한계와 이행이 주는 소득상실의 위험을 최소화하기 위한 우선과제로서 국가복지의 확대와 이행지원 전략을 제안하였다.