• Journal of Educational Research in Mathematics
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• v.9 no.2
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• pp.383-404
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• 1999

This study began with an epistemological question about the nature of mathematical cognition in relation to the learner's activity. Therefore, by examining Piaget's 'reflective abstraction' theory which can be an answer to the question, we tried to get suggestions which can be given to the mathematical education in practice. 'Reflective abstraction' is formed through the coordination of the epistmmic subject's action while 'empirical abstraction' is formed by the characters of observable concrete object. The reason Piaget distinguished these two kinds of abstraction is that the foundation for the peculiar objectivity and inevitability can be taken from the coordination of the action which is shared by all the epistemic subjects. Moreover, because the mechanism of reflective abstraction, unlike empirical abstraction, does not construct a new operation by simply changing the result of the previous construction, but is forming re-construction which includes the structure previously constructed as a special case, the system which is developed by this mechanism is able to have reasonability constantly. The mechanism of the re-construction of the intellectual system through the reflective abstraction can be explained as continuous spiral alternance between the two complementary processes, 'reflechissement' and 'reflexion'; reflechissement is that the action moves to the higher level through the process of 'int riorisation' and 'thematisation'; reflexion is a process of 'equilibration'between the assimilation and the accomodation of the unbalance caused by the movement of the level. The operational learning principle of the theorists like Aebli who intended to embody Piaget's operational constructivism, attempts to explain the construction of the operation through 'internalization' of the action, but does not sufficiently emphasize the integration of the structure through the 'coordination' of the action and the ensuing discontinuous evolvement of learning level. Thus, based on the examination on the essential characteristic of the reflective abstraction and the mechanism, this study presents the principles of teaching and learning as following; $\circled1$ the principle of the operational interpretation of knowledge, $\circled2$ the principle of the structural interpretation of the operation, $\circled3$ the principle of int riorisation, $\circled4$ the principle of th matisation, $\circled5$ the principle of coordination, reflexion, and integration, $\circled6$ the principle of the discontinuous evolvement of learning level.

• Journal of Educational Research in Mathematics
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• v.13 no.3
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• pp.351-364
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• 2003

by A.C. Clairaut is the first geometry textbook based on the historico-genetic principle against the logico-deduction method of Euclid's This paper aims to recognize Clairaut's historico-genetic principle by inquiring into this book and to search for its applications to school mathematics. For this purpose, we induce the following five characteristics that result from his principle and give some suggestions for school geometry in relation to these characteristics respectively : 1. The appearance of geometry is due to the necessity. 2. He approaches to the geometry through solving real-world problems.- the application of mathematics 3. He adopts natural methods for beginners.-the harmony of intuition and logic 4. He makes beginners to grasp the principles. 5. The activity principle is embodied. In addition, we analyze the two useful propositions that may prove these characteristics properly.

• Korea Trade Review
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• v.43 no.4
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• pp.89-110
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• 2018

This paper reviews the practical operations and exceptions to the independent principle by analyzing the leading cases of English documentary credit transactions. A bank's undertaking in L/C transactions differentiates between underlying contract and other contracts. The autonomy principle is the key principle governing L/C, but this principle may be connected with unfair (unjust) payment. English Law is strongly influenced by the developments in American Law in the case of fraud, but traditionally, British courts has been very reluctant to interfere in banks' independent undertaking under the L/C. The position of British case law relating to fraud is based on Sztejn. In practice, British courts recognize fraud as an exception to the autonomy principle in which the case is sufficiently serious to render it unjust to permit the beneficiary to receive payment. British case law has historically taken a narrow approach toward intervention in the independent principle of documentary credit. Therefore, innocent parties including beneficiaries are protected by these regulations regarding fraud.

• Journal of the Korean Data and Information Science Society
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• v.21 no.2
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• pp.327-333
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• 2010

This study examines the impact different proxies of agency costs have on companies under different governance approaches. The two specific proxies of agency costs used include: (i) the ratio of operating expenses to annual sales; and (ii) the ratio of annual sales to total assets. Our study is based on earlier works of Ang et al. (2000) and Fleming et al. (2005). A comparison of results for small unlisted companies both in US and Australia indicate that agency cost measures have statistically: (1) different result under rule-based governance mechanisms; and (2) the same results under principle-based governance mechanisms. Our findings support the view that the effectiveness different measures of agency cost is dependent on country specific governance facto as well as on the governance approaches adopted. Our results offer insights to both practitioners and policy makers regarding the usefulness of different proxies of agency costs when companies adopt principle-based corporate governance approaches versus rule-based approaches.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.18 no.6B
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• pp.219-232
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• 2008

A novel idea of protocol security analysis is presented based on trusted freshness. The idea has been implemented not only by hand but also by a belief muitisets formalism for automation. The key of the security analysis based on trusted freshness is a freshness principle: for each participant of a cryptographic protocol, the security of the protocol depends only on the sent or received one-way transformation of a message, which includes a trusted freshness. The manual security analysis method and the belief multisets formalism are all established on the basis of the freshness principle. Security analysis based on trusted freshness can efficiently distinguish whether a message is fresh or not, and the analysis results suggest the correctness of a protocol convincingly or the way to construct attacks intuitively from the absence of security properties. Furthermore, the security analysis based on trusted freshness is independent of the idealization of a protocol, the concrete formalization of attackers' possible behaviors, and the formalization of concurrent runs of protocols.

• Journal of Korean Medical classics
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• v.32 no.1
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• pp.1-27
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• 2019

Objectives : By studying the contents of Zhang Yuansu's "Zhenmairushijie", which are introductory remarks of "Chandobangronmaekkyulgipseong", this study attempts to clarify the academic meaning expressed in it and consider his real significance. Methods : First, based on previous studies on Zhang Yuansu and "Wangshuhemaijue", this study divides the contents of "Zhenmairushijie" into 4 chapters and read out the original text. Next, based on Zhang Yuansu's notes and other writings on the original text, this study examines contents in detail. Finally, based on the discussion, this study examines the current significance of academic thoughts expressed in Zhang Yuansu's "Zhenmairushijie". Results ＆ Conclusions : "Zhenmairushijie" emphasizes the combination of nervation and Byeonggi in the process of feeling the pulse for diagnosis, the combination of Byeonggi and Yongyak to declare that the feeling of the pulse for diagnosis is the principle of differential diagnosis. The combination principle of nervation-Byeonggi can be found in comprehensive pulse methods of "Nanjing", and the combination of Byeonggi-Yongyak should follow Ohaeng's Bubuheoshilsajeongbosa principle. Pulse methods of "Wangshuhemaijue" integrated Byeonggi expressed in Uigyeong and Byeonggi in Gyeongbang in the process of the feeling of the pulse for diagnosis to present the principle of diagnosis to perform Byeongjeungronchi. Therefore, "feeling the pulse for diagnosis ipsik" is not only an introductory remark of feeling the pulse for diagnosis, but an comprehensive remark of whole diagnosis as well. It is an introductory remark of the entire medical field due to the nature of oriental medicine which emphasizes diagnosis.

• Journal of Computational Design and Engineering
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• v.3 no.3
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• pp.191-197
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• 2016

Since 3D measurement technologies have been widely used in manufacturing industries edge detection in a depth image plays an important role in computer vision applications. In this paper, we have proposed an edge detection process in a depth image based on the image based smoothing and morphological operations. In this method we have used the principle of Median filtering, which has a renowned feature for edge preservation properties. The edge detection was done based on Canny Edge detection principle and was improvised with morphological operations, which are represented as combinations of erosion and dilation. Later, we compared our results with some existing methods and exhibited that this method produced better results. However, this method works in multiframe applications with effective framerates. Thus this technique will aid to detect edges robustly from depth images and contribute to promote applications in depth images such as object detection, object segmentation, etc.

• Proceedings of the KIEE Conference
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• 1991.07a
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• pp.411-416
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• 1991

Operation simulation is a key factor to evaluate investment and operation in a power utility. Probabilistic production simulation is of major concern. With pumped-storage plant, production simulation is not an easy task, because its economy should fully be exploited. In addition, usual operation interval is a week rather than a day. Most existing models are based on approximate production simulation such as adopting simple priority orders of generations. This study is based on the more elaborate model developed by authors. Further, a policy of weekly coordination is established based on the Maximum Principle. Chronological load curve instead of usual load duration curve is used and the accuracy in simulation is enhahced. Resulting economics are compared. Deviation between these two toad curve is shown.

• Steel and Composite Structures
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• v.21 no.3
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• pp.553-571
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• 2016

The progressive collapse potential of steel moment framed structures due to abrupt removal of a column is investigated based on the energy principle. Based on the changes of component's internal energy, this paper analyzes structural member's sensitivity to abrupt removal of a column to determine a sub-structure resisting progressive collapse. An energy-based structural damage index is defined to judge whether progressive collapse occurs in a structure. Then, a simplified beam damage model is proposed to analyze the energies absorbed and dissipated by structural beams at large deflections, and a simplified modified plastic hinges model is developed to consider catenary action in beams. In addition, the correlation between bending moment and axial force in a beam during the whole deformation development process is analyzed and modified, which shows good agreement with the experimental results.

• Journal of the Semiconductor & Display Technology
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• v.23 no.2
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• pp.92-99
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• 2024

As semiconductor processes require several nanometers precision, the importance of motor control is increasing in semiconductor equipment. Due to unpredictable uncertainties such as friction and mechanical vibrations achieving precise position control in semiconductor processes is challenging. The internal model principle-based controller is a control technique that ensures robust steady-state performance by incorporating a model of the reference and disturbance. The disturbance observer-based controller is a prominent robust control technique implemented to cope with various nonlinearities and uncertainties. Provided that the two controllers can be designed to exhibit equivalent performance under certain conditions, this paper demonstrates through experiments that they yield identical results for the case of a BLDC position control problem. The experimental results also indicate that they can offer enhanced robustness compared with the conventional PID controller in the presence of a time-varying disturbance.