• Structural Engineering and Mechanics
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• v.10 no.2
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• pp.157-164
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• 2000

This paper discusses the error propagation characteristics of the Newmark explicit method, modified Newmark explicit method and ${\alpha}$-function dissipative explicit method in pseudodynamic tests. The Newmark explicit method is non-dissipative while the ${\alpha}$-function dissipative explicit method and the modified Newmark explicit method are dissipative and can eliminate the spurious participation of high frequency responses. In addition, error propagation analysis shows that the modified Newmark explicit method and the ${\alpha}$-function dissipative explicit method possess much better error propagation properties when compared to the Newmark explicit method. The major disadvantages of the modified Newmark explicit method are the positive lower stability limit and undesired numerical dissipation. Thus, the ${\alpha}$-function dissipative explicit method might be the most appropriate explicit pseudodynamic algorithm.

• Proceedings of the Korean Information Science Society Conference
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• 2002.10e
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• pp.352-354
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• 2002

Explicit multicast 는 narrowcast 기술의 일종으로써 소수의 참여자가 참가하는 다수의 멀티캐스트 그룹을 지원하는데 효과적인 멀티캐스트 프로토콜이다. 기존의 멀티캐스트기술에 비해 Explicit multicast 는 세션별 정보를 유지하고 있지 않기 때문에 네트워크 대역폭을 절약할 수 있고 확장성에 대한 강점을 가지고 있다. 본 연구에서는 Explicit multicast 프로토콜의 특징들을 분석해 보고 Explicit multicast 프로토콜을 지원하는 라우터를 Linux 기반 플랫폼에서 동작하도록 구현하여 Explicit multicast 실험 네트워크를 구축한다. 또한 Explicit multicast 프로토콜 응용프로그램을 개발하여 구축된 Explicit multicast 네트워크와 연동시켜 프로토콜의 동작을 확인한다. 이러한 개발 및 실험 결과를 바탕으로 향후 Explicit multicast 프로토콜이 효과적으로 사용되기 위한 개선점들을 제안한다.

• Journal of Korean Elementary Science Education
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• v.38 no.4
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• pp.484-495
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• 2019

This study divided pre-service elementary school teachers' knowledge conversion into four types, socialization, externalization, combination and internalization, based on their inquiry activities on the life cycle of cabbage butterfly. As research subjects, this study collected results from 24 pre-service elementary school teachers who carried out inquires on the life cycle of cabbage butterfly for about 2 months. The type of socialization indicates the conversion of tacit knowledge into tacit knowledge, and this study found out that pre-service elementary school teachers acquired and accumulated tacit knowledge from their fellow pre-service teachers, professors and even acquaintances inside and outside the lab. However, there appeared no process that they shared their tacit knowledge with other pre-service teachers or delivered it to them. The type of externalization indicates the conversion of tacit knowledge into explicit knowledge, and this study discovered some cases that pre-service elementary school teachers expressed their inner tacit knowledge into explicit knowledge. However, there was no case found that they converted the verbally-unexpressed tacit knowledge of their fellow teachers or experts into well-defined explicit knowledge. The type of combination indicates the conversion of explicit knowledge into explicit knowledge, and this study discovered some cases that they collected explicit knowledge and converted it into new explicit knowledge for the acquisition, integration and delivery or distribution of explicit knowledge. However, there were few cases that they creatively devised new explicit knowledge by acquiring new knowledge through direct observation and supplementing the existing explicit knowledge. The type of internalization indicates the conversion of explicit knowledge into tacit knowledge, and this study discovered both explicit knowledge embodied through personal experiences and explicit knowledge embodied through simulations and experiments that formed tacit knowledge in process of examining the existing explicit knowledge.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.27 no.12
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• pp.1724-1733
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• 2003

This paper assesses the prediction performance of explicit algebraic stress and heat-flux models for reduction of heat transfer coefficient in a strongly-heated vertical tube. Two explicit algebraic stress models and four explicit algebraic heat-flux models are selected for assessment. Eight combinations of explicit algebraic stress and heat-flux models are used in predicting the turbulent gas flows with intense heating, which yields the significant property-variation. The results showed that the two combinations of GS-AKN and WJ-mAKN predicted the Nusselt number and the axial wall temperature variations well and that the predictions of Nusselt number with WJ-combinations spread in a wider range than those with Gs-combinations. WJ is the explicit algebraic stress model of Wallin and Johansson and GS is the model of Gatski and Speziale and that AKN is the explicit heat-flux model of Abe, Kondoh and Nagano and mAKN is the modified AKN.

• Transactions of Materials Processing
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• v.3 no.1
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• pp.84-96
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• 1994

Simulation of 3 dimensional large irregularly shaped stamping process by a dynamic approach, based on an explicit time integration scheme, has been shown to be highly efficient and robust in comparison to traditional, implicit, quasi-static ones. The objective of the work is to evaluate the results from explicit code in application to deep drawing of rectangular cup and stamping of automotive front fender, in which deformation, force, thickness distribution are calculated. The method of predicting spring back and formability by and explicit code are suggested and applied to the processes.

• ETRI Journal
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• v.36 no.3
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• pp.396-406
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• 2014

We have designed and investigated a new congestion control scheme, called optimal and fully explicit (OFEX) controller. Different from existing relatively explicit controllers, this new scheme can provide not only optimal bandwidth allocation but also a fully explicit congestion signal to sources. It uses the congestion signal from the most congested link instead of the cumulative signal from the flow path. In this way, it overcomes the drawback of relatively explicit controllers exhibiting bias toward multi-bottlenecked users and significantly improves their convergence speed and source throughput performance. Furthermore, our OFEX-controller design considers a dynamic model by proposing a remedial measure against the unpredictable bandwidth changes in contention-based multi-access networks. Compared with former works/controllers, this remedy also effectively reduces the instantaneous queue size in a router and thus significantly improves queuing delay and packet loss performance. We have evaluated the effectiveness of the OFEX controller in OPNET. The experimental comparison with the existing relatively explicit controllers verifies the superiority of our new scheme.

• Transactions of the Korean Society of Automotive Engineers
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• v.2 no.4
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• pp.50-58
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• 1994

To examine the residual stress field resulting from stamping process for the lower control arm of a car, the explicit finite element analysis is performed for the stamping process by way of the ABAQUS Explicit. The residual stress is obtained in terms of the Von Mises stress and other parameters such as equivalent plastic strain, the change of blank thickness, the final configuration of the blank and the spring back effect are also considered. Moreover, discussed is the convergence of the explicit FEM versus the punch sped and the element discretization

• English Language & Literature Teaching
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• v.8 no.1
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• pp.39-53
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• 2002

Recently much research has investigated the role of attention in L2 learning, comparing the effects of explicit learning with those of implicit learning. With this background the research aims at examining the effects explicit focus on form has on L2 learning based on the acquisition of the English article system. The participants were 70 Korean college students who enrolled in English Composition classes. The experimental group received explicit focus on form including grammatical explanation, input enhancement, output practice, and negative evidence (corrective feedback) for two weeks, while the control group was exposed to sufficient input and negative evidence. Completion tasks were administered at the beginning and the end of the semester. In addition, errors in the use of English articles were analysed on their compositions both before and after the different treatments. The analyses of the results show that the explicit focus on form group improved significantly more than the control group, particularly for the definite article 'the', and some changes occurred in the distribution of article errors. These findings suggest that explicit teaching plays a more contributory role than implicit teaching in acquiring L2 knowledge in classroom-based L2 learning.

• Asia pacific journal of information systems
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• v.11 no.4
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• pp.113-133
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• 2001

We propose utilizing a fuzzy cognitive map(FCM) to integrate tacit knowledge and explicit knowledge both of which are crucial to the success of knowledge management. Recently, explicit knowledge is getting more available as CRM and data mining approaches become popular as the advent of using database and the Internet technology. However, for the knowledge management to be successful, tacit knowledge should be seamlessly integrated with explicit knowledge seamlessly. The problem hindering such effort is how to find a vehicle facilitating transformation of explicit knowledge into tacit knowledge, and vice versa. FCM has been important method for representing tacit knowledge as a form of explict knowledge. In this respect, we suggest the detailed process about how to integrate explicit knowledge and tacit knowledge by using FCM. We gathered extensive set of data from the credit card company, and applied our proposed method. Results showed that our approach is robust and promising for the field of integrating two different kinds of knowledge.

• The KIPS Transactions:PartA
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• v.13A no.2 s.99
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• pp.177-184
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• 2006

Since well-known explicit methods for cloth simulation were regarded unstable for large time steps or stiff springs, implicit methods have been proposed to achieve the stability. Large time step makes the simulation fast, and large stiffness enables a less elastic cloth property. Also, there have been efforts to devise so-called semi-implicit methods to achieve the stability and the speed together. In this paper we improve Kang's method (Kang and Cho 2002), and thus devise a scalable method for cloth simulation that varies from an almost explicit to a full implicit method. It is almost as fast as explicit methods and, more importantly, almost as stable as implicit methods allowing large time steps and stiff springs. Furthermore, it has a less artificial damping than the previously proposed semi-implicit methods.