• 4차산업연구
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• 제1권2호
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• pp.9-16
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• 2021

Purpose - O2O (online to off-line) is a new economic concept being emerged in the 4^th industrial age. Automobile distribution is also undergoing a change to the O2O system. In overseas, vehicles are already being sold through various online platforms. The purpose of this study is to analyze the domestic and foreign automobile distribution structure and intends to suggest the desirable direction of automobile sales in the 4th industrial age. Research design, data, and methodology - Through the investigation of previous studies and the actual cases, the advantages and disadvantages and trends of different types of automobile distribution structures. Result - It can be seen that domestic and foreign automobile brands have quite diverse distribution structures such as direct managed system, agency system, dealer system, direct sales system, online system and online/offline parallel system. Each type has its own characteristics. Conclusion - The distribution structure of automobiles is very diverse, and in particular, it is rapidly changing to an online sales system thanks to the development of information and communication technology and Internet technology and the popularization of smartphones. Through the online system, consumers can quickly and conveniently obtain vehicle information. Although the online sales system has many advantages, it requires continuous management

• 4차산업연구
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• 제2권1호
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• pp.1-8
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• 2022

Purpose - O2O (online to off-line) is a new economic concept being emerged in the 4^th industrial age. Automobile distribution is also undergoing a change to the O2O system. In overseas, vehicles are already being sold through various online platforms. The purpose of this study is to analyze the domestic and foreign automobile distribution structure and intends to suggest the desirable direction of automobile sales in the 4th industrial age. Research design, data and methodology - Through the investigation of previous studies and the actual cases, the advantages and disadvantages and trends of different types of automobile distribution structures. Result - It can be seen that domestic and foreign automobile brands have quite diverse distribution structures such as direct managed system, agency system, dealer system, direct sales system, online system and online/offline parallel system. Each type has its own characteristics. Conclusion - The distribution structure of automobiles is very diverse, and in particular, it is rapidly changing to an online sales system thanks to the development of information and communication technology and Internet technology and the popularization of smartphones. Through the online system, consumers can quickly and conveniently obtain vehicle information. Although the online sales system has many advantages, it requires continuous management.

• Journal of Radiation Protection and Research
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• 제43권2호
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• pp.59-65
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• 2018

Background: We analyzed changes in the doses, structure volumes, and dose-volume histograms (DVHs) when data were transferred from one commercial treatment planning system (TPS) to another commercial TPS. Materials and Methods: A total of 22 volumetric modulated arc therapy (VMAT) plans for nasopharyngeal cancer were generated with the Eclipse system using 6-MV photon beams. The computed tomography (CT) images, dose distributions, and structure information, including the planning target volume (PTV) and organs at risk (OARs), were transferred from the Eclipse to the MRIdian system in digital imaging and communications in medicine (DICOM) format. Thereafter, DVHs of the OARs and PTVs were generated in the MRIdian system. The structure volumes, dose distributions, and DVHs were compared between the MRIdian and Eclipse systems. Results and Discussion: The dose differences between the two systems were negligible (average matching ratio for every voxel with a 0.1% dose difference criterion = $100.0{\pm}0.0%$). However, the structure volumes significantly differed between the MRIdian and Eclipse systems (volume differences of $743.21{\pm}461.91%$ for the optic chiasm and $8.98{\pm}1.98%$ for the PTV). Compared to the Eclipse system, the MRIdian system generally overestimated the structure volumes (all, p < 0.001). The DVHs that were plotted using the relative structure volumes exhibited small differences between the MRIdian and Eclipse systems. In contrast, the DVHs that were plotted using the absolute structure volumes showed large differences between the two TPSs. Conclusion: DVH interpretation between two TPSs should be performed using DVHs plotted with the absolute dose and absolute volume, rather than the relative values.

• 한국전기전자재료학회논문지
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• 제19권4호
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• pp.328-333
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• 2006

In this paper, we developed a pressure measurement apparatus with the parallel structure to improve the measurement efficiency of pressure sensors by reducing the measurement time of pressure. The developed system has two parallel positions for loading Silicon pressure sensor and has a dual valve structure. The semiconductor pressure sensors prepared by Copal Electronics were used to confirm the performance of the developed measurement system. Two stage differential amplifier circuit was employed to amplify the weak output signal and the amplified output signal was improved utilizing a low-pass filter. New apparatus shows the measurement time of pressure two times shorter than that of conventional one with the serial structure, while both structures show the similar linear output versus pressure characteristics.

• 연구논문집
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• 통권29호
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• pp.83-90
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• 1999

In naval ships, pump machineries are the major sources of airborne and structure-borne noise. Noise is critical issue in ships not only it causes annoyance to crews, but also it can increase the underwater radiated noise, which is crucial in anti-submarine warfare. In present study, it is discussed the reduction of structure-borne noise of pump machineries by showing several examples. The most typical and effective solution is to use double resilient mount system. However, in cases where double resilient system cannot be applied due to space and weight increase, rubber pad can be used to reduce the structure-borne noise. In principle, the concept of structure-borne noise reduction is the same as that of vibration isolation.

• 국제강구조저널
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• 제18권5호
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• pp.1598-1606
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• 2018

An integrated optimal structural design method for a diagrid structure and control device was developed. A multi-objective genetic algorithm was used and a 60-story diagrid building structure was developed as an example structure. Artificial wind and earthquake loads were generated to assess the wind-induced and seismic responses. A smart tuned mass damper (TMD) was used as a structural control system and an MR (magnetorheological) damper was employed to develop a smart TMD (STMD). The multi-objective genetic algorithm used five objectives including a reduction of the dynamic responses, additional stiffness and damping, mass of STMD, capacity of the MR damper for the integrated optimization of a diagrid structure and a STMD. From the proposed method, integrated optimal designs for the diagrid structure and STMD were obtained. The numerical simulation also showed that the STMD provided good control performance for reducing the wind-induced and seismic responses of a tall diagrid building structure.

• 해양환경안전학회:학술대회논문집
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• 해양환경안전학회 2007년도 춘계학술발표회
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• pp.133-139
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• 2007

본 연구는 해상교통정보시스템의 정보제공에 대한 구조를 퍼지구조모델법을 이용하여 분석하였다. 일반적으로 퍼지구조모델법에서는 임계치와 파라메타의 선정의 어려움으로 인해 시스템의 전체적인 구조를 파악하기가 어려웠다. 따라서 본 연구에서는 계층구조 그래프와 분할도를 이용하여 해상교통정보시스템의 정보제공에 대한 전체적인 구조를 분석할 수 있었다. 또한 몇가지의 예를 통해 모델의 해석과 실제 문제점을 제시하고 분석하였다.

• 정보관리학회지
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• 제33권3호
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• pp.155-176
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• 2016

본 연구는 한국학 연구 논문 텍스트의 의미 구조를 기반으로 하는 메타데이터를 적용한 학술정보시스템을 구축하여 기존 유사 시스템과의 비교를 통해, 텍스트 구조 기반 메타데이터의 활용 가능성을 확인해 보고자 하는 것을 목적으로 한다. 이를 위해 한국학술지인용색인(Korea Citation Index, KCI)에서 일정 기준을 충족하는 한국학 분야 연구 논문 데이터를 대상으로 의미 구조 메타데이터 항목을 적용한 시범적 검색 시스템(Korean Studies Metadata Database, KMD)을 구축하였으며, 동일한 검색 키워드를 적용하여 기존의 KCI 시스템과 비교했을 때 어떤 특징과 차이점을 갖는지 비교해 보았다. 연구 결과, KMD 시스템이 KCI에 비해 이용자의 검색 의도에 맞는 결과를 보다 효율적으로 보여주는 것으로 확인되었다. 즉 검색하고자 하는 키워드의 조합이나 조건식이 기존 시스템과 동일하더라도 검색 결과를 통해 최종적으로 연구 진행과 관련해 찾고자 하는 연구 목적, 연구의 대상 데이터나 시공간적 배경 등에 따른 검색 결과를 다양하게 보여줄 수 있는 것으로 나타났다.

• 한국군사과학기술학회지
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• 제3권1호
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• pp.13-25
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• 2000

A simulation model is developed to analyze the large-structure driving system and its integrated behavior in the whole weapon system. It models every component in the driving system such as mechanical and electrical characteristics, and it is programmed by simulation language in a way which strongly reflects the system's real time dynamics and reduces computation time as well. A useful parameter identification method is proposed, and it is tuned on the given physical system. The model is validated through comparing to real test, and it is applied to analysis and prediction of integrated system functions relating to the fire control system.

• 한국산업융합학회 논문집
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• 제26권5호
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• pp.825-831
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• 2023

The propellers used for big ships have a large diameter and are very heavy. In order to apply a precise and safe work process to them, it is necessary to use an exclusive turning system. For this reason, various techniques are applied to produce them. However, workers' convenience and safety are not taken into consideration enough at production sites. Conventionally, these propellers are designed to be separated as their turning system is loaded and rotated by empty weight. Therefore, it is necessary to replace such a design. This study tries to find the weaknesses of the design and structure of a conventional propeller turning system for large ships, to verify structure integrity of a structure in structural analysis, and to devise a plan for designing a new type of turning system. In the basic concept design and structural analysis for the turning system used in the propeller finishing process for large ships, this study drew the following conclusions. It was possible to develop the work process of the turning system for the propeller finishing process used for large ships, to obtain the dimensions for exterior design through a basic design. Structural analysis was conducted to find the structure integrity of the turning system. As a result, in the rail installed to transfer a gantry, the maximum stress was about 45MPa, about 5.5 times lower than the yield strength 250MPa. Therefore, the turning system was judged to be safe structurally.