• 한국과학교육학회지
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• 제25권1호
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• pp.41-56
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• 2005

Assessing students' knowledge can be a challenging endeavor, as researchers attempt to capture the full complexity and potential development of children's ideas. In this study, the Dynamic Science Assessment (DSA) method (Magnusson, Templin, and Boyle, 1997) was employed to investigate 9-12 year old students' understandings of light, while engaging in multiple tasks with a flashlight with various reflectors and mirrors. The results showed that DSA was effective in providing an opportunity to establish a Zone of Proximal Development, in addition to diagnosing a student's prior understanding. Throughout the interview, a student showed a conceptual model of light as being a solid single entity whose shape can be determined by the shape of the casing of a flashlight. However, as DSA provided phenomena that could not be explained by his unitary model, the student began to re-examine his original conceptual model, and attempted to revise it. This study addressed how Dynamic Science Assessment can help us better understand, not only students' current state of understanding, but also a potential development of understanding in their ZPD. In that sense, this study argues that we should pay more attention to the instructive role of classroom assessment that can promote and support further development of students' deeper understandings.

• Structural Engineering and Mechanics
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• 제41권4호
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• pp.539-558
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• 2012

The diagnosis of bridge serviceability is carried out by a combination of in-situ visual inspection, static and dynamic loading tests and analyses. Structural health monitoring (SHM) using information technology and sensors is increasingly being used for providing a better estimate of structural performance characteristics rather than above traditional methods. Because the mechanical behavior of bridges with various kinds of damage can not be made clear, it is very difficult to estimate both the damage mode and degree of damage of existing bridges. In this paper, the sensitivity of both static and dynamic behaviors of bridges are studied as a measure of damage assessment through experiments on model bridges induced with some specified artificial damages. And, a method of damage assessment of bridges based on those behaviors is discussed in detail. Finally, based on the results, a possible application for structural health monitoring systems for existing bridges is also discussed.

• 한국지능시스템학회:학술대회논문집
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• 한국퍼지및지능시스템학회 1998년도 The Third Asian Fuzzy Systems Symposium
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• pp.552-555
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• 1998

In dealing with representing knowledge under uncertainty there is a sustain tendency to increase flexibility in order to avoid problems of inconsistency in the knowledge. Many knowledge systems(information retrieval systems, expert system) include hybrid representation models. Funny retrieval systems appear as a complement or as an enrichment of this models. In this paper, we describe dynamic rule modification through situation assessment for uncertainty management.

• Nuclear Engineering and Technology
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• 제48권2호
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• pp.386-403
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• 2016

The safety of nuclear power plants is analyzed by a probabilistic risk assessment, and the fault tree analysis is the most widely used method for a risk assessment with the event tree analysis. One of the well-known disadvantages of the fault tree is that drawing a fault tree for a complex system is a very cumbersome task. Thus, several graphical modeling methods have been proposed for the convenient and intuitive modeling of complex systems. In this paper, the reliability graph with general gates (RGGG) method, one of the intuitive graphical modeling methods based on Bayesian networks, is improved for the reliability analyses of dynamic systems that have various operation modes with time. A reliability matrix is proposed and it is explained how to utilize the reliability matrix in the RGGG for various cases of operation mode changes. The proposed RGGG with a reliability matrix provides a convenient and intuitive modeling of various operation modes of complex systems, and can also be utilized with dynamic nodes that analyze the failure sequences of subcomponents. The combinatorial use of a reliability matrix with dynamic nodes is illustrated through an application to a shutdown cooling system in a nuclear power plant.

• 영재교육연구
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• 제22권3호
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• pp.703-728
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• 2012

이 연구의 목적은 초등 과학 영재를 교수 및 평가하는 데 있어 종래의 정적 방법이 아닌 역동적 방법을 채택하여 전기회로 개념 이해 과정을 분석해 보는 것이다. 초등 과학 영재 11명을 대상으로 과학적인 전기회로 개념으로의 이해를 의도한 역동적 과학 평가를 실시하여 스캐폴딩 양상을 중심으로 변화 과정을 알아보고, 영재학생의 개념 변화 과정에서 나타나는 특징을 분석하였다. 연구 결과 첫째, 역동적 과학 평가를 통해 초등 과학영재의 개념 이해에 유용한 스캐폴딩 투입 특성을 확인하였다. 둘째, 역동적 과학 평가 전략에 의한 개념 정립이 개별 학생의 특성에 따라 다양한 방식으로 나타났다. 셋째, 전기회로 개념 이해의 각 장면에서 효과적으로 작용했던 전략을 확인할 수 있었다.

• 농업과학연구
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• 제43권3호
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• pp.468-480
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• 2016

As the existing FTAs' implementations are being accelerated, ex-post assessments, such as tariff schedules and agricultural trade analyses results, have been emerging as important national issues for the agricultural sector. Korea-Chile FTA is the first FTA in Korea, and more than ten years have passed since April 2004. It will be necessary to measure the impacts of the agreement on the domestic agricultural industry by analyzing concessions made on traded items of farm products on prices, agricultural trade, and so on. The purpose of this study is to prepare for the request for ex-post assessments on the agricultural sector by trade negotiation procedural law. Additionally, by providing policy direction for agricultural policy segments requiring amendments and supplements through an ex-post assessment, we can more objectively evaluate the conflicting arguments between the agricultural and non-agricultural sectors. Current evaluation methods about ex-post impact assessment of FTA are generally comparison analysis on the change of trade balance before and after FTA implementation. However, this simple comparison analysis cannot be said to pure FTA effects and objective, tightening economic impact assessment of the FTA because of all combined situations such as effects of exchange rates, international macroeconomic changes, climate change, and the occurrence of pests. This research attempts to use dynamic analysis as its ex-post assessment methodology and is expected to contribute to future policy evaluation.

• 환경영향평가
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• 제13권4호
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• pp.213-222
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• 2004

Exergy is defined as the amount of work (entropy-free energy) a system can perform when it is brought into thermodynamic equilibrium with its environment. Exergy measures the distance from the inorganic soup in energy terms. Therefore, exergy can be considered as fuel for any system that converts energy and matter in a metabolic process. The aim of this study is to introduce structural dynamic modelling which is based on maximum exergy principle. Especially, almost ecological models couldn't explain algal succession until now. New model (structural dynamic model) is anticipated to predict or explain the succession theory. If the new concept using maximum exergy principle is used, algal succession can be explained in many actual cases. Therefore, It is estimated that structural dynamic model using maximum exergy principle might be a excellent tool to understand succession of nature from now on.

• 한국학교수학회논문집
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• 제9권4호
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• pp.459-479
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• 2006

본 연구는 탐구형 기하소프트웨어의 활용이 중학교 기하영역에서 추론능력의 평가에 어떻게 적용될 수 있을지, 그리고 어떤 영향을 끼칠 수 있을지에 관한 것이다. 이를 위하여 작도, 귀납적 추론, 연역적 추론이 통합되는 형태로 문항을 구성하여 5명의 학생을 대상으로 사례 연구를 실시하였고 그 결과를 학생의 작도능력, 귀납적 추론 능력, 정당화의 유형이라는 세 관점에서 분석하였다. 연구 결과 소프트웨어를 활용한 평가문항은 학생의 추론능력을 분명히 드러나게 할 수 있음을 알 수 있었다. 또한 교사는 소프트웨어의 활용을 통해 귀납추론 평가문항을 폭넓고 용이하게 만들 수 있음을 확인하였다.

• 한국농공학회논문집
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• 제64권2호
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• pp.71-83
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• 2022

In this study, an indicator and assessment system for evaluating the monthly hydrological cycle was prepared using simple factors such as the landuse status of the watershed and topographic characteristics to the dynamic water balance model (DWBM) based on the Budyko framework. The parameters a1 of DWBM are introduced as hydrologic cycle indicators. An indicator estimation regression model was developed using watershed characteristics data for the introduced indicator, and an assessment system was prepared through K-means cluster analysis. The hydrological cycle assessment system developed in this study can assess the hydrological cycle with simple data such as land use, CN, and watershed slope, so it can quickly assess changes in hydrological cycle factors in the past and present. Because of this advantage is expected that the developed assessment system can predict changes in the hydrological cycle and use an auxiliary tool for policymaking.

• Food Science and Biotechnology
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• 제15권6호
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• pp.856-859
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• 2006

The effects of moisture content on non-fracture dynamic properties and fracture gel quality of Pacific whiting surimi were investigated to determine their relationships. Surimi samples were tested at various moisture contents (75, 78, and 81 %). Torsion test showed that shear stress decreased rapidly and strain values decreased gradually as moisture concentration increased. Dynamic storage modulus (G') also decreased as moisture content increased. A strong positive correlation ($R^2=0.90$ to 0.99) was found between the G' measured at temperatures between 10 and $45^{\circ}C$ and fracture stress values. The results indicate that dynamic rheological measurements could be used as a tool for early gel quality assessment.