• 한국과학교육학회지
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• 제42권1호
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• pp.33-49
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• 2022

본 연구는 창의 과정과 산물의 구조적 관계를 분석한 정량적 자료와 정성적 자료를 활용하여 초등학생의 과학 창의성 유형을 탐색하였다. 이를 위해 초등학교 5학년 105명의 학생이 창의 과정과 산물을 나타내는 과학 창의성 검사 도구에 응답한 내용과 그중 과학 창의성이 가장 높았던 4명을 대상으로 주로 어떤 과정으로 창의 산물을 냈는지 면담하여 자료를 수집하였다. 검사 결과에 대해 상관관계 및 구조방정식 분석을 하였고 면담 자료와 함께 유형화의 참고자료로 사용하였다. 연구 결과는 다음과 같다. 첫째, 창의 과정과 산물의 구조방정식 모형은 절대적합지수와 증분적합지수 측면에서 적합도가 검증되었다. 둘째, 지식, 탐구기능 중 관찰, 창의적 사고기능의 창의 과정 중 창의적 사고기능만이 창의 산물에 유의한 영향을 미쳤다. 셋째, 창의적 사고기능 중 과학 창의성 산물과의 연관성은 확산적 사고, 수렴적 사고, 연관적 사고 순으로 나타났다. 넷째, 초등학생의 과학 창의성은 산물에 따라 창의형, 유용형, 독창형, 비창의형으로 유형이 나뉜다. 그중 비창의형은 세부적으로 진부형, 반복형, 미응답형, 비타당형, 추상형으로 나뉜다. 다섯째, 초등학생은 창의 과정에서 지식 혹은 관찰 중 하나를 주로 사용하는 양상을 보였는데, 이에 따라 지식 지향형, 관찰 지향형으로 유형화할 수 있다. 또한, 창의적 사고기능을 얼마나 다양하게 사용했는지에 따라 DT형, DT-CT형, DT-CT-AT형 등으로 나눌 수 있다. 이 연구는 교육자와 연구자가 과학 창의성 교육에 실질적으로 고려해야 할 점을 시사하고 있다.

• 한국정밀공학회지
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• 제13권7호
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• pp.100-114
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• 1996

In order to create a solid model more efficiently for a plastic or sheet metal product with a thin and constant thickness, various methods have been proposed up to now. One of the most typical approaches is to create a sheet model initially and then transform it into a solid model automatically for a given thickness. The sheet model as well as the transitive model in sheet modeling procedure is a non-manifold model. However, the previous methods adopted the boundary representations for a solid model as their topological framework. Thus, it is difficult to represent the exact adjacency relationship between topological entities and to implement the topological operations for sheet modeling and the transformation procedure of a sheet into a solid. In this paper, we proposed a sheet modeling system based on a non-manifold topological representation which can represent solids, sheets, wireframes, and their mixture. A set of generalized Euler operators for non-manifold topology as well as the sheet modeling capabilities including adding, bending, and punching functions are provided for easy modeling of sheet objects, and they are perfomed interactively with a two dimensional curve editor. Once a sheet model is completed, it can be transformed into a solid automatically. The transformation procedure is composed of the offset functions and the Boolean operations of sheet models, and it is even more comprehensive and easier to be implemented than the precious methods.

• Journal of Power Electronics
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• 제16권3호
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• pp.970-981
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• 2016

Leakage currents occur in pulse-width-modulated voltage source inverter (PWM-VSI)-fed permanent magnet synchronous motor (PMSM) drives for air-conditioners, which seriously affect system safety and operation performance. High accuracy modeling and prediction of leakage currents are key issues for the design and implementation of air-conditioning products. In this study, the generation mechanism of leakage currents is discussed. A systematic modeling approach of leakage currents is proposed, including the modeling of leakage current sources and leakage current paths. By using the proposed approach, the complete model of leakage currents in PWM-VSI-fed PMSM drives for air-conditioners has been developed based on the extraction of all parameters. A comparison between the simulated leakage currents based on the developed model and measured leakage currents in the outdoor unit of an air-conditioning product is conducted. The comparison verifies the effectiveness of the proposed modeling approach, and the developed model exhibits high accuracy within a wide frequency range.

• 한국시뮬레이션학회:학술대회논문집
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• 한국시뮬레이션학회 2003년도 추계학술대회 및 정기총회
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• pp.185-192
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• 2003

Digital Manufacturing-based production could be very effective in shipbuilding in order to save costs and time, to increase safety for workers, and to prevent bottleneck processes in advance. Digital shipbuilding system, a simulation-based production tool, is being developed to achieve such aspects in Korea. To simulate material flow in a subassembly line at a shipyard, the product, process and resources was modeled for the subassembly process which consisted of several sub-processes such as tack welding, piece alignment, tack welding, and robot welding processes. The analysis and modeling were carried out by using the UML(Unified Modeling Language), an object-oriented modeling method as well as IDEF(Integration DEFinition), a functional modeling tool. Initially, the characteristics of the shop resources were analyzed using the shipyard data, and the layout of the subassembly line was designed with the resources. The production process modeling of the subassembly lines was performed using the discrete event simulation method. Using the constructed resource and process model, the productivity and efficiency of the line were investigated. The number of workers and the variations In the resource performance such as that of a new welding robot were examined to simulate the changes in productivity. The bottleneck process floated according to the performance of the new resources. The proposed model was viewed three-dimensionally in a digital environment so that interferences among objects and space allocations for the resources could be easily investigated

• 지능정보연구
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• 제17권4호
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• pp.1-17
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• 2011

오늘날 글로벌한 경쟁에서 고객의 만족도를 유지하고 생산성과 효율을 높이기 위해서 대량맞춤(mass customization)이 많은 선도기업에서 채택되고 있다. 대량맞춤은 제품가족과 제품 플랫폼에 근거하여 기업으로 하여금 새로운 제품을 유연하고 효율적이며 고객 요구에 신속히 대응하는 것을 용이하게 한다. 따라서 제품 플랫폼에 기반한 제품가족 전략이 대량맞춤을 실현화하는데 적절한 방법이다. 제품가족이란 다양한 시장의 요구를 충족하기 위해서 공통의 특성, 구성부품, 서브 시스템을 공유하는 일련의 유사한 제품군으로 정의된다. 이 연구의 목표는 제품가족 설계 전략을 이용하여 고객의 요구를 충족시키는 제품의 구성부품간의 우선순위를 찾아내고자 하는 것이다. 신 제품 개발을 위한 의사결정 과정은 피드백을 가지는 다 변량 의사결정 모형을 필요로 한다. 이를 위해서 분석적 네트워크 과정(analytic network process) 방법을 이용하여 의사결정 모델과 절차를 수립하였다. 구현을 위해서 제품가족 모델에 적합한 소형 PC인 넷북 제품을 선정하고, 각 제품가족에 대한 구성부품에 대하여 제안된 방법에 따라서 우선순위를 도출하였다. 구현결과를 QFD 모델을 이용하여 고객요구사항과 구성부품간의 관계를 분석하고 평가하였다.

• The Journal of Asian Finance, Economics and Business
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• 제7권6호
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• pp.221-231
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• 2020

This research investigates the relationship among product risk, financial risk, security risk, privacy risk, perceived satisfaction, and purchase intention. Validated measurements were identified from a literature review. The measurement model and the conceptual model depicting hypothesized relationships were evaluated based on responses from 306 customers using confirmatory factor analysis and structural equation modeling. The results showed that product risk, financial risk, security risk, and privacy risk impacted on perceived satisfaction. Besides, product risk, privacy risk, and perceived satisfaction influenced purchase intentions. Thus, this study focused on the influences of product risk, financial risk, security risk, and privacy risk on their cognitive attitudes toward websites. That means the more consumer perceive security, the more they avoid shopping online. The study is important to show how perceived risk affects online shopping behaviors, and it invites marketers to make necessary adjustments to prevent perceived risks to increase and online shopping to decrease. The findings of this study suggest the creation of a framework on the effect of perceived risk types on online shopping. Managers need to take perceived risks into account when designing their electronic marketing channels. In addition, shopping websites should strengthen their transaction security by appropriately using various available resources and new information technologies.

• 산업경영시스템학회지
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• 제32권1호
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• pp.102-110
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• 2009

Concurrent Engineering(CE) has presented new possibilities for successful product development by incorporating various product life-cycle functions from the earlier stage of design. In the product design, geometric representation is vital not only in its traditional role as a means of communicating design information but also in its role as a means of externalizing designer's thought process by visualizing the design product. During the last dozens of years, there has been extraordinary development of computer-aided tools intended to generate, present or communicate 3D models. However, there has not been comparable progress in the development of 3D-CAD systems intended to represent and manipulate a variety of product life-cycle information in a consistent manner. This paper proposes a novel concept, Minus Volume (MV), to incorporate various design information relevant to product lift-cycle functions. MV is a functional shape that is extracted from a design object within a bounding box. A prototype 3D-CAD system is implemented based on the MV concept and illustrated with the successful implementation of concurrent design and manufacturing.

• 한국원자력학회:학술대회논문집
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• 한국원자력학회 1996년도 춘계학술발표회논문집(2)
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• pp.637-642
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• 1996

This paper presents the analysis results for the core degradation processes and the fission product release of the PHEBUS FPT0 experiment using MELCOR1.8.3. The objective of this study is to assess models associated with the core damage and fission product behavior in MELCOR. The calculation results were much improved through sensitivity studies. Thermal/hydraulic behavior in the core and the circuit was well predicted under the intact core geometry. In non-eutectic model case. the UO$_2$ dissolution model in the MELCOR always showed such a tendency that the resulting dissolved UO$_2$ mass was small at the highly oxidized condition due to the model logic. Total H$_2$ generation mass was underpredicted because the stiffner was not modeled and the liner in the shroud was not allowed to be oxidized in MELCOR. Some difficulties were found in modeling the activation product were solved by manipulating the RN input associated with the initial fission product inventory. These problem were occurred because there are no control rod model in MELCOR. Generally the fission product release ratio showed a similar trend compared with the measured data except the activation product. which have no model to simulate in MELCOR.

• 지식경영연구
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• 제14권3호
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• pp.87-100
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• 2013

As the external knowledge networks of firms have become more and more important to their product and service innovations, many global leading companies such as P & G, IBM, and Samsung Electronics have formulated and implemented their open innovation strategy. This study attempts to empirically analyze the effects of CEOs' supports for external knowledge networks, external knowledge network-oriented cultures and inter-organizational knowledge management systems as the major antecedents to external knowledge networks by using the data based on organizational members' perceptions about them. Based on 847 samples collected from employees in three companies in the medical, the construction and the IT service industries, this study performed a structural equation modeling (SEM) analysis about the effects of the antecedents to the external knowledge networks on product and service innovations through Partial Least Squares (PLS). The empirical findings of this study show that CEOs' supports for external knowledge network positively influence product and service innovations, partially mediated by external knowledge network-oriented cultures and inter-organizational knowledge management systems. And they also show that external knowledge network-oriented cultures and inter-organizational knowledge management systems have a positive effect on product and service innovations, respectively, partially mediated by external knowledge networks. With these new findings, academic and practical implications are discussed.

• 한국CDE학회논문집
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• 제7권3호
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• pp.157-169
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• 2002

In the initial stages of ship design, designers represent geometry, arrangement, and dimension of hull structures with 2D geometric primitives such as points, lines, arcs, and drawing symbols. However, these design information(‘2D geometric primitives’) defined in the drawing sheet require more intelligent translation processes by the designers in the next design stages. Thus, the loss of design semantics could be occurred and following design processes could be delayed. In the initial design stages, it is not easy to adopt commercial 3D CAD systems, which have been developed f3r being used in detail and production design stages, because the 3D CAD systems require detailed input for geometry definition. In this study, a semantic product model data structure was proposed, and an initial structural CAD system was developed based on the proposed data structure. Contents(‘product model data and design knowledges’) of the proposed data structure are filled with minimal input of the designers, and then 3D solid model and production material information can be automatically generated as occasion demands. Finally, the applicability of the proposed semantic product model data structure and the developed initial structural CAD system was verified through application to deadweight 300,000ton VLCC(Very Large Crude oil Carrier) product modeling procedure.