• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.32 no.1
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• pp.20-24
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• 2019

Ferroelectric material properties are strongly governed by domain structures and their evolution processes, but the evolution processes of complex domain patterns during a macroscopic electrical poling process are still elusive. In the present work, domain-evolution processes in a PZT ceramic near the morphotropic phase-boundary composition were studied during a step-wise electrical poling using piezoresponse force microscopy (PFM). Electron backscatter diffraction was used with the PFM data to identify the grain boundaries in the region of interest. In response to an externally the applied electric field, growth and retreat of non-$180^{\circ}$ domain boundaries wasere observed. The results indicate that ferroelectric polarization-switching nucleates and evolves in concordance with the pattern of the pre-existing domains.

• International Journal of Computer Science & Network Security
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• v.21 no.3
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• pp.153-164
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• 2021

The increasing importance of such fields as embedded systems, pervasive computing, and hybrid systems control is increasing attention to the time-dependent aspects of system modeling. In this paper, we focus on modeling conceptual time. Conceptual time is time represented in conceptual modeling, where the notion of time does not always play a major role. Time modeling in computing is far from exhibiting a unified and comprehensive framework, and is often handled in an ad hoc manner. This paper contributes to the establishment of a broader understanding of time in conceptual modeling based on a software and system engineering model denoted thinging machine (TM). TM modeling is founded on a one-category ontology called a thimac (thing/machine) that is used to elaborate the design and analysis of ontological presumptions. The issue under study is a sample of abstract modeling domains as exemplified by time. The goal is to provide better understanding of the TM model by supplementing it with a conceptualization of time aspects. The results reveal new characteristics of time and related notions such as space, events, and system behavior.

• Journal of the Korean Society for Precision Engineering
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• v.12 no.8
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• pp.39-52
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• 1995

In order to design and improve a new machine tool, there is a need for a better understanding of the dynamic cutting force. In this paper, the computer programs were developed to predict the dynamic cutting force by the mean specific cutting pressure in the face milling process. The simulated cutiing forces in X, Y, Z directions resulted from the developed dynamic cutting force model are compared with the measured cutiing forces in the time and frequency domains. The simulated cutting force model have a good agreement with the measured forces in comparison with those resulted from the existing cutting force model.

• Educational Technology International
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• v.6 no.2
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• pp.69-85
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• 2005

The purpose of the article is to address a new instructional approach to a complex engineering course. We design a novel instructional method that combines mobile technology, simulation program, collaborative teamwork, problem-solving process, and a variety of evaluation techniques. We suggested five instructional principles that might be required to change the fundamental educational process by which learning is done. The proposed instructional method is expected to aspire for new perspectives on complex learning environment. Nevertheless we solely began by the research on the development of students' complex problem-solving performance in a complex engineering course, the new instructional method in the article can promote the adoption of new instructional methods and strategies across different knowledge domains. In addition, the instructional method can provide a valuable bridge to acquisition and transfer of problem solving, motivation, and meaning learning.

• Asia pacific journal of information systems
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• v.32 no.4
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• pp.916-944
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• 2022

Artificial Intelligence has been a conceptual area for several decades. It has been studied extensively through experiments by the Information Systems community. When Information Systems supported with Information Technology became all pervasive in business and other allied areas, gradually the advancements in Artificial Intelligence also emerged as innovations across domains. Artificial Intelligence by definition is expected to substitute Human Intelligence, thereby making a huge space for innovation. In fact, all processes effected by human intelligence are liable to be replaced by AI which in itself is a massive innovation space. This paper will study the publication's repository (Scopus and Google Scholar from 1983 till 2021) in the area of Artificial Intelligence and innovation, then analyze the trend to gain insight into the evolution of AI as a vehicle for innovation.

• Journal of The Korean Association For Science Education
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• v.27 no.8
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• pp.724-742
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• 2007

The purpose of this study was to develop a scientific inquiry model that makes scientific inquiry accessible to science teachers as well as students. To develop a scientific inquiry model, we investigated the research process demonstrated by ten scientists who were working at academic research institutions or industrial research institutions. We collected data through scientists' journal articles, lab meetings and seminars, and observation of their inquiry process. After we analyzed the scientists' inquiry strategies and processes of inquiry, we finally developed the Scientist's Methodology of Investigation Process model named SMIP. The SMIP model consists of four domains, 15 stages, and link questions, such as "if, why", and "how". The SMIP model stressed that inquiry process is a selective process rather than a linear or a circular process. Overall, these findings can have implication science educators in their attempt to design instruction to improve the scientific inquiry process.

• Korean Journal of Computational Design and Engineering
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• v.11 no.1
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• pp.57-66
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• 2006

Modeling product configurations needs large amounts of knowledge about technical and marketing restrictions on the product. Previous attempts to automate product configurations concentrate on representations and management of the knowledge for specific domains in fixed and isolated computing environments. Since the knowledge about product configurations is subject to continuous change and hard to express, these attempts often failed to efficiently manage and exchange the knowledge in collaborative product development. In this paper, XML Topic Map (XTM) is introduced to represent and exchange the knowledge about product configurations in collaborative product development. A product configuration model based on XTM along with its merger and inference facilities enables configuration engineers In collaborative product development to manage and exchange their knowledge efficiently. An implementation of the proposed product configuration model is presented to demonstrate that the proposed approach enables enterprises to exchange the knowledge about product configurations during their collaborative product development.

• 유체기계공업학회:학술대회논문집
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• 2002.12a
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• pp.152-157
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• 2002

A cross-flow fan is widely used on many industrial fields: a blower for the general industry, mining industry, automobile and home appliances. The design point of the cross-flow fan is generally chosen by based on the region within low static pressure and high flow rate. It relatively makes high dynamic pressure at low speed because a working fluid passes through an impeller blade twice. However, it has low static pressure efficiency between $30\%$ and $40\%$ because of relative high impact loss. Recently, in the air-conditioning systems, the operating behaviors at the off-design points are highly regarded to broaden the application area for various air-cooling loads. Especially, at the low flow rate, there exists a rapid pressure head reduction, a noise increase and an irregular flow against a rearguider as a scroll of centrifugal fan. Numerical analyses are carried out for cross-flow fan including the impeller, the rearguider and the stabilizer. Numerical domains are discretized by hexahedral cells. Three-dimensional, unsteady governing equations are solved using FVM, SIMPLE algorithm, sliding grid system and standard k-$\epsilon$ turbulence model.

• Journal of Korea Society of Digital Industry and Information Management
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• v.11 no.3
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• pp.21-29
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• 2015

The Internet of Things (IoT) is an Infrastructure which allows to connect with each device in physical world through the Internet. Thus IoT enables to provide meahup services or intelligent services to human user using collected data from those devices. Due to these advantages, IoT is used in divers service domains such as traffic, distribution, healthcare, and smart city. However, current IoT provides restricted services because it only supports monitor and control devices according to collected data from the devices. To resolve this problem, we propose a design and implementation of personalized IoT service base on service orchestration. The proposed service allows to discover specific services and then to combine the services according to a user location. To this end, we develop a service ontology to interpret user information according to meanings and smartphone web app to use the IoT service by human user. We also develop a service platform to work with external IoT platform. Finally, to show feasibility, we evaluate the proposed system via study.

• Korean Institute of Interior Design Journal
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• v.16 no.2 s.61
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• pp.105-114
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• 2007

As a result of imminent recognition on nature from modern world, the need for the combination between architecture and nature has been raised as another topic in architectural arena, and this kind of work is being conducted under the notion of Landscape. As the term 'Landscape' emerges as the key word in contemporary architecture, 'Landscape' begins to transcend the mere meaning of landscape architecture(gardening). The word, Landscape, has gone beyond the meaning of mere landscape, or rural vista one-dimensionally, and, after having introduced the attributes of nature into building activities, has emerged as a notion trying to form 'the architecture as landscape.' Together with these, 'Landscape' is expanding as a notion having various layers. The notion's, 'Landscape', occupying the significant position in contemporary architecture has been a recent phenomenon over 1980-1990s, and its category of practice has not certain limitation, rather it has started simultaneously from various areas. This study, before reviewing the architectural notion of Landscape by studying the Landscape notion and its various embodying methods being shown in contemporary architecture. As a result of examining the features of Landscape notion shown in various directions(ways), being influenced by the four Landscape types presented by Eduard Bru and the currents of the times, we can see that, though the features are somewhat similar, they are classified and explained as different types respectively. So, we are able to recategorize the features into 6 domains in this study.