• Title/Summary/Keyword: extension principle

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Analysis of Elementary Science Lesson Plans on Shadow Principle - Focusing on the Types and Cognitive Processes of Visual Representations - (그림자 원리에 대한 초등 과학 수업 지도안 분석 - 시각적 표상의 유형과 인지 과정을 중심으로 -)

  • Yoon, Hye-Gyoung
    • Journal of Korean Elementary Science Education
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    • v.39 no.1
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    • pp.26-39
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    • 2020
  • Visual Representation Competence Taxonomy (VRC-T) was developed in previous study(Yoon, 2018) to provide a framework conducive to assess visual representation competence and to devise appropriate educational activities for it. This study is an extension of the previous study. It aimed to explore the usefulness of VRC-T and revise it by analyzing the patterns of visual representation use in science lessons. The researcher collected lesson plans on shadow principle from 11 pre-service and 13 in-service elementary teachers and conducted individual interviews regarding what visual representations they considered and how they tried to use them in science lessons. VRC-T was used as an analytical framework to examine the types and cognitive processes of visual representations. As a result, new categories were added and the revised VRC-T was completed (VRC-TR). It was also found that both pre- and in-service teachers mainly focused on 'interpreting' the 'descriptive representation' while designing their lesson plans. Additionally, in-service teachers showed more limited use of visual representations compared to pre-service teachers. In-service teachers largely relied on the national science textbooks, while pre-service teachers reflected their own learning experiences in their teacher-training program. These results showed that teachers' use of visual representations heavily relied on their prior learning and teaching experiences. The VRC-TR presented in this study and examples of class activities in each category can be helpful for teachers and researchers who want to use visual representations more effectively.

ST Reliability and Connectivity of VANETs for Different Mobility Environments

  • Saajid, Hussain;DI, WU;Memon, Sheeba;Bux, Naadiya Khuda
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.13 no.5
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    • pp.2338-2356
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    • 2019
  • Vehicular ad-hoc network (VANET) is the name of technology, which uses 'mobile internet' to facilitate communication between vehicles. The aim is to ensure road safety and achieve secure communication. Therefore, the reliability of this type of networks is a serious concern. The reliability of VANET is dependent upon proper communication between vehicles within a given amount of time. Therefore a new formula is introduced, the terms of the new formula correspond 1 by 1 to a class special ST route (SRORT). The new formula terms are much lesser than the Inclusion-Exclusion principle. An algorithm for the Source-to-Terminal reliability was presented, the algorithm produced Source-to-Terminal reliability or computed a Source-to-Terminal reliability expression by calculating a class of special networks of the given network. Since the architecture of this class of networks which need to be computed was comparatively trivial, the performance of the new algorithm was superior to the Inclusion-Exclusion principle. Also, we introduce a mobility metric called universal speed factor (USF) which is the extension of the existing speed factor, that suppose same speed of all vehicles at every time. The USF describes an exact relation between the relative speed of consecutive vehicles and the headway distance. The connectivity of vehicles in different mobile situations is analyzed using USF i.e., slow mobility connectivity, static connectivity, and high mobility connectivity. It is observed that $p_c$ probability of connectivity is directly proportional to the mean speed ${\mu}_{\nu}$ till specified threshold ${\mu}_{\tau}$, and decreases after ${\mu}_{\tau}$. Finally, the congested network is connected strongly as compared to the sparse network as shown in the simulation results.

Volatile Compounds and Ultrastructure of Petal Epidermal Cells According to Scent Intensity in Rosa hybrida (장미꽃의 향기정도에 따른 주요성분 및 꽃잎 세포의 미세구조)

  • Lee, Young-Soon;Lee, Yun-Hae;Lim, Seung-Hee;Park, Gun-Hwan;Choi, Sunk-Young;Hong, Hae-Jung;Ko, Jeong-Ae
    • Horticultural Science & Technology
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    • v.31 no.5
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    • pp.590-597
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    • 2013
  • Principle component and emission localization of volatile compounds were investigated according to scent intensity of rose flower. Scent intensity in cultivars and bred-line of Rosa hybrida was divided into three levels; light ('Feel Lip', 'Venus Berry'), medium ('GR07-135'), strong ('Honey Blue'). The major volatile compounds were different depending on the cultivars and selected line; 3,5-dimethoxytoluene (DMT), benzene, 1,3,5-trimethoxy ('Feel Lip'), megastigma-4,6(Z),8(E)-triene ('Venus Berry'), DMT, benzene,1-ethenyl-4-methoxyand, phenylethylalcohol ('GR07-135') and germacrene-D, DMT ('Honey Blue'). The adaxial epidermal cells were conical papillate shape, whereas the abaxial epidermal cells were flat shape. The adaxial epidermal cells of 3 cultivars and 1 selected line were surrounded by thick cell wall and covered by waxy cuticle of 2 cultivars and 1 selected line (except 'Honey Blue'). The adaxial epidermal cells contained starches in 'Feel Lip', osmiophlic droplets in 'Venus Berry', starchs, plastids, vacuoles in 'GR07-135' and plastoglobules, plastids, vacuoles in 'Honey Blue'. Based on these results, it appears that plastids and vacuoles in adaxial epidermal cells with conical papillate shape are associated production and emission of volatile compounds in scent R. hybrida.

A Study on Extension of One-bit of the Parallel Interface type Digital-to-Analog Conversion Circuit (병렬 인터페이스형 디지털/아날로그 변환회로의 1개 비트 확장에 관한 연구)

  • Kwon, Sung-Yeol;Lee, Hyun-Chang
    • Journal of Convergence for Information Technology
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    • v.11 no.8
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    • pp.1-7
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    • 2021
  • In this paper, a method of extending 1 bit by adding an external device to a parallel interface type Digital-to-Analog conversion(D/A C) circuit is presented. To do this, the principle of the D/A C circuit was examined, and the problems that occur when extending one bit by adding individual devices were analyzed, and a bit extension method of the D/A devices using an OP-Amp. circuit was presented. As the proposed method uses the high-precision characteristics of the OP-Amp., even if an error occurs in the device, only the overall size of the output waveform is affected, and the voltage reversal phenomenon that occurs between each bit does not occur. In order to confirm the effect of the proposed method, an experimental circuit was constructed and the absolute voltage of the output and the relative error were measured. As a result, a voltage error of 0.0756% appeared, confirming that the 0.195% requirement for one bit expansion by adding individual devices was sufficiently satisfied.

Learning Framework for Robust Planning and Real-Time Execution Control

  • Wang, Gi-Nam;Yu, Gang
    • Management Science and Financial Engineering
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    • v.8 no.1
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    • pp.53-75
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    • 2002
  • In this Paper, an attempt is made to establish a learning framework for robust planning and real-time execution control. Necessary definitions and concepts are clearly presented to describe real-time operational control in response to Plan disruptions. A general mathematical framework for disruption recovery is also laid out. Global disruption model is decomposed into suitable number of local disruption models. Execution Pattern is designed to capture local disruptions using decomposed-reverse neural mappings, and to further demonstrate how the decomposed-reverse mappings could be applied for solving disrubtion recovery problems. Two decomposed-reverse neural mappings, N-K-M and M-K-N are employed to produce transportation solutions in react-time. A potential extension is also discussed using the proposed mapping principle and other hybrid heuristics. Experimental results are provided to verify the proposed approach.

Mathematical modeling of actively controlled piezo smart structures: a review

  • Gupta, Vivek;Sharma, Manu;Thakur, Nagesh
    • Smart Structures and Systems
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    • v.8 no.3
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    • pp.275-302
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    • 2011
  • This is a review paper on mathematical modeling of actively controlled piezo smart structures. Paper has four sections to discuss the techniques to: (i) write the equations of motion (ii) implement sensor-actuator design (iii) model real life environmental effects and, (iv) control structural vibrations. In section (i), methods of writing equations of motion using equilibrium relations, Hamilton's principle, finite element technique and modal testing are discussed. In section (ii), self-sensing actuators, extension-bending actuators, shear actuators and modal sensors/actuators are discussed. In section (iii), modeling of thermal, hygro and other non-linear effects is discussed. Finally in section (iv), various vibration control techniques and useful software are mentioned. This review has two objectives: (i) practicing engineers can pick the most suitable philosophy for their end application and, (ii) researchers can come to know how the field has evolved, how it can be extended to real life structures and what the potential gaps in the literature are.

A ray-based approach to scattering from inhomogeneous dielectric objects (전파경로 투적에 의한 비균질 유전체의 전자파 산란)

  • Kim, Hyeongdong
    • Journal of the Korean Institute of Telematics and Electronics A
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    • v.32A no.2
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    • pp.31-37
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    • 1995
  • A ray-based approach is developed to calculate the scattering from inhomogeneous dielectric objects. This approach is a natural extension of the "shooting and bouncing ray(SBR)" technique developed earlier for calculating the radar cross section of cavity structures and complex targets. In this formulation, a dense grid of rays representing the incident field is shot toward the scatterer. The curved trajectory, amplitude, phase and polarization of the ray fields inside the inhomogeneous object are computed numerically based on the laws of geometrical optics. The contributions of the exting rays to the exterior scattered field are then calculated by using the equivalence principle in conjunction with " a ray-tube integration" scheme. The ray-based approach is applied for the effect of an arcjet plasma plume on satellite reflector performance and backscattering from inhomogeneous objects.

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A note on T-sum of bell-shaped fuzzy intervals

  • Hong, Dug-Hun
    • Journal of the Korean Institute of Intelligent Systems
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    • v.17 no.6
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    • pp.804-806
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    • 2007
  • The usual arithmetic operations on real numbers can be extended to arithmetical operations on fuzzy intervals by means of Zadeh's extension principle based on a t-norm T. Dombi and Gyorbiro proved that addition is closed if the Dombi t-norm is used with two bell-shaped fuzzy intervals. Recently, Hong [Fuzzy Sets and Systems 158(2007) 739-746] defined a broader class of bell-shaped fuzzy intervals. Then he study t-norms which are consistent with these particular types of fuzzy intervals as applications of a result proved by Mesiar on a strict f-norm based shape preserving additions of LR-fuzzy intervals with unbounded support. In this note, we give a direct proof of the main results of Hong.

A Study for Contemporary Fashion Trend in Extended Cultural Conception (확장문화개념에서의 90년대 유행 Fashion의 경향에 대한 연구)

  • 이은영
    • The Research Journal of the Costume Culture
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    • v.5 no.4
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    • pp.54-67
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    • 1997
  • Now, this time we regarde as daylife is a part of culture in novelty view of modern culture study. Specially, we can see terms about style surfing supermarket style through visulization process for critic, combination, reconstruction, of modernism, that is post modernism. Not new style show up any more but displayed union of past style history complex, slices of decoration series. A designer group called as memphis, they designed such like that. Our view for fashion could be new in the technology, mixed media, cyber situation is stimulated us and accepted in extened concept of culture. In this study, I approched as a view of streetism cyber punkism haute couture Romanticism linked extension concept of culture. Haute couture fashion has the most historical, and constructive and decorative aspects, and regarded as principle of construction of deconstruction. And this season trend is romantic & emotional image are complexed.

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Shortest Path Problem in a Type-2 Fuzzy Weighted Graph (타입 2-퍼지 가중치 그래프에서 최단경로 문제)

  • 이승수;이광형
    • Journal of the Korean Institute of Intelligent Systems
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    • v.11 no.6
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    • pp.528-531
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    • 2001
  • Finding a shortest path on a graph is a fundamental problem in the area of graph theory. In an application where we cannot exactly determine the weights of edges fuzzy weights can be used instead of crisp weights. and Type-2 fuzzy weight will be more suitable of this uncertainty varies under some conditions. In this paper, shortest path problem in type-1 fuzzy weighted graphs is extended for type 2 fuzzy weighted graphes. A solution is also given based on possibility theory and extension principle.

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