• 제목/요약/키워드: evaluation of stages of use

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샌드위치 복합재 철도차량 루프구조물의 구조안전성 평가 (Evaluation of the Structural Integrity of a Sandwich Composite Train Roof Structure)

  • 신광복;류봉조;이재열;이상진;조세현
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2005년도 추계학술대회 논문집
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    • pp.338-343
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    • 2005
  • We have evaluated the structural integrity of a sandwich composite train roof which can find a lightweight, cost saving solution to large structural components for rail vehicles in design stages. The sandwich composite train roof was 11.45 meter long and 1.76 meter wide. The reinforced frame was inserted in sandwich panels to improve the structural performance of train roof structure and had the shape of hollow rectangular box. The finite-element analysis was used to calculate the stresses, deflections and natural frequencies of the sandwich composite train roof against the weight of air-condition system. The 3D sandwich FE model was introduced to simulate the hollow aluminum frames which jointed to both sides of the sandwich train roof. The results shown that the structural performance of a sandwich composite train roof under load conditions specified was proven and the use of aluminum reinforced frame was beneficial with regard to weight savings in comparison to steel reinforced frame.

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피로균열시 발생되는 AE신호 분석 (Evaluation of AE Signal caused by the Fatigue Crack)

  • 김재구;구동식;최병근
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2011년도 춘계학술대회 논문집
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    • pp.572-577
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    • 2011
  • The acoustic emission (AE) technique is a well-known non-destructive test technique, both in research and for industrial applications. It is mainly used to monitor the onset of cracking processes in materials and components. Predicting and preventing the crack phenomenon has attracted the attention of many researchers and has continued to provide a large incentive for the use of condition monitoring techniques to detect the earliest stages of cracks. In this research, goal is in grasping features of AE signal caused by crack growth. The envelope analysis with discrete wavelet transform (DWT) is used to find the characteristic of AE signal. To estimate feature of divided into three by crack length, the time waveform and the power spectrum were generated by the raw signals and the transferred signal processed by envelope analysis with DWT.

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건설현장 시공과정의 탄소배출량 예측 시나리오 구축에 관한 연구 (A Fundamental Study on the Construction Scenario for Prediction of Carbon Emissions in Construction Site)

  • 이충원;임효진;태성호
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2023년도 가을학술발표대회논문집
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    • pp.247-248
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    • 2023
  • As carbon neutrality becomes an issue around the world, research is actively being conducted to achieve reduction targets for each industry by declaring 2050 carbon neutrality in Korea and implementing the greenhouse gas target management system and emission trading system. The construction industry quantitatively predicts and evaluates carbon emissions by stages through the evaluation of the entire building process, but research on this is insufficient in the case of the construction process. Therefore, as part of the research on predicting and reducing carbon emissions generated at construction sites, data from actual construction sites were collected to analyze the facilities and characteristics of each energy source, and a scenario was proposed to quantitatively predict the use of each energy source.

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The use of culture systems for the study of oligodendrocyte development and injury: The erbB2 gene is required for the development of terminally differentiated spinal cord oligodendrocytes

  • Park, Song-Kyu;Kim, Hwan-Mook;Vartanian, Timothy
    • 한국환경성돌연변이발암원학회:학술대회논문집
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    • 한국환경성돌연변이발암원학회 2002년도 Current Trends in Toxicological Sciences
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    • pp.14-23
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    • 2002
  • Development of oligodendrocytes and the generation of myelin internodes within the spinal cord depends on regional signals derived from the notochord and axonally derived signals. Neuregulin (NRG)-1, localized in the floor plate as well as in motor and sensory neurons, is necessary for normal oligodendrocyte development. Oligodendrocytes respond to NRGs by activating members of the erbB receptor tyrosine kinase family. Here, we show that erbB2 is not necessary for the early stages of oligodendrocyte precursor development, but is essential for proligodendroblasts to differentiate into galactosylcerebroside-positive (GalC+) oligodendrocytes. In the presence of erbB2, oligodendrocyte development is normal. In the absence of erbB2 (erbB2-/-), however, oligodendrocyte development is halted at the proligodendroblast stage with a >10-fold reduction in the number of GalC+ oligodendrocytes. ErbB2 appears to function in the transition of proligodendroblast to oligodendrocyte by transducing a terminal differentiation signal, since there is no evidence of increased oligodendrocyte death in the absence of erbB2. Furthermore, known survival signals for oligodendrocytes increase oligodendrocyte numbers in the presence of erbB2, but fail to do so in the absence of erbB2. Of the erbB2-/- oligodendrocytes that do differentiate, all fail to ensheath neurites. These data suggest that erbB2 is required for the terminal differentiation of oligodendrocytes and for development of myelin.

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재난 취약계층을 위한 GPS 기반 Self Triage 앱 개발 (Development of GPS based Self Triage App for Disaster Vulnerable Populations)

  • 박주영
    • 기본간호학회지
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    • 제24권3호
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    • pp.230-242
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    • 2017
  • Purpose: The purpose of this study was to develop a self triage application for rescue requests by disaster vulnerable populations. Literature was reviewed in order to define application trends and needs. Methods: Development of the self triage application was conducted in six stages as a hybrid model (analysis, design, development, implementation, evaluation, modification) of the ADDIE (Analysis, Design, Development, Implementation, Evaluation) model and Driscoll & Alexander model. Application system function and contents were tried with 6 experts and 4 people with hearing impairments. Results: Expert assessment of the application for self triage showed that reliability at 5 points was the highest, followed by utility at 4.8 points. Scores for quickness and expressiveness were low at 4.6 and 4.2 points respectively. User acceptability assessment of the application was measured at 66.73 points. Conclusion: The results show that the application for self triage is helpful to disaster vulnerable populations by providing relief in disaster situations. It is expected that use of this application as a self rescue ability can be made available for disaster situations. However, it will be necessary to establish policies for communication strategies with rescuers and public relations to improve the access rate of disaster app service.

Implementation of an Autostereoscopic Virtual 3D Button in Non-contact Manner Using Simple Deep Learning Network

  • You, Sang-Hee;Hwang, Min;Kim, Ki-Hoon;Cho, Chang-Suk
    • Journal of Information Processing Systems
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    • 제17권3호
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    • pp.505-517
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    • 2021
  • This research presented an implementation of autostereoscopic virtual three-dimensional (3D) button device as non-contact style. The proposed device has several characteristics about visible feature, non-contact use and artificial intelligence (AI) engine. The device was designed to be contactless to prevent virus contamination and consists of 3D buttons in a virtual stereoscopic view. To specify the button pressed virtually by fingertip pointing, a simple deep learning network having two stages without convolution filters was designed. As confirmed in the experiment, if the input data composition is clearly designed, the deep learning network does not need to be configured so complexly. As the results of testing and evaluation by the certification institute, the proposed button device shows high reliability and stability.

The Development of the Engineering Leadership Program for Engineering Students

  • Kim, In-Sook
    • 공학교육연구
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    • 제17권4호
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    • pp.21-24
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    • 2014
  • The purpose of this study is to develop the engineering students leadership program and evaluate the pilot test. To this end, literature reviews covering various leadership programs were studied and a needs analysis survey was conducted. The needs analysis survey found that student subjects believe leadership to be an important quality, but that the current availability of leadership training programs is lacking. Furthermore, results of the study are as follows, with respective results listed in descending order. The majority of students selected on-line learning as their preferred training method, followed by blended learning and in-person learning. Students also indicated their preferred instructional method to be through on-line courses. Based on these results, a preliminary pilot program was experimentally launched for only 1 class's use. This process of the development for the Engineering Leadership Program consists of 4 stages. The first stage is a needs analysis survey, followed by the design of the program based on results from the needs analysis survey. Afterwards comes the development stage, followed by the implementation stage, comprised of two parts; the pilot test and the distribution. The final stage is the overall evaluation step. We are currently in the first step of the third stage (the pilot test) and only the overall evaluation stage remains. After the distribution, a follow-up study will be conducted to analyze the effectiveness of the implemented program.

건물용 태양열과 지열의 보급 장벽 평가 (Evaluation of Deployment Barriers to Solar Thermal and Ground Source Heat Pump for Buildings)

  • 조일현;이재석
    • 신재생에너지
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    • 제20권1호
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    • pp.61-69
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    • 2024
  • This study investigates the barriers to the deployment of solar thermal and ground source heat pump (GSHP) from the perspective of consumers and businesses, as well as evaluates priorities for improving the barriers via expert AHP evaluation. From a consumer's perspective, the overall satisfaction with solar thermal is significantly lower than that with PV and needs to be improved at the installation and use stages. GSHP needs to be improved at the prior-information search stage. From a business perspective, the non-distinction between heat and electricity in mandatory installations in public buildings, the difficulty in assessing the value of heat, and high initial costs impede the deployment. Based on the result of AHP analysis, the priorities for improving the barriers to the wide utilization of solar thermal are evaluated in the order of economic feasibility, policy, acceptability, and technology, where high installation cost is shown to be the greatest barrier. Barriers for GSHP are evaluated in the order of policy, acceptability, economic feasibility, and technology, where policy means improvement is evaluated as the most important factor in promoting the deployment of GSHP.

팽창줄눈의 이론적 산정 (Theoretical Evaluation on Spacings of Expansion Joint)

  • 이홍재;이차돈
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 1999년도 학회창립 10주년 기념 1999년도 가을 학술발표회 논문집
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    • pp.455-458
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    • 1999
  • It has been known that buildings having inappropriate expansion joints in their spacings may be subject to exterior damages due to extensive cracks on the outer walls under service loads, and structural damages due to excessive moment induced by temperature changes at ultimate load conditions. Rather inconsistent code provisions are available regarding spacings of expansion joints from different foreign structural codes and even worse, no quantiative measure on spacings is given in our codes for building structures. In order to establish a rational measure on the spacing of expansion joints, theoretical approaches are taken in this study. The developed theoretical formula is, then, converted to design chart for structural designer's convenience in its use. The chart considers both service and ultimate load stages.

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텍스타일 디자인 캐드 시스템의 색정리 기능에 대한 정량적 분석 연구 (A Study on the Color Functions of the Textile Design System based on CAD using Image Analysis Methods)

  • 최경미;김종준
    • 패션비즈니스
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    • 제15권4호
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    • pp.43-54
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    • 2011
  • Printing process has been a major sector in the textile industries for a long period of time. With the advent of digital textile printing, the complex procedures of printing preparations and after-treatment processes have been streamlined. For the design of the motives of images to be printed, the use of image handling software, e.g. Photoshop(Adobe), has been of prime importance. Even though the software is extremely useful and functionally versatile, there are many laborious steps involved for the specific textile printing process. The use of a CAD-based textile printing function may help the textile printing process in streamlining the complex processing stages. The image qualities of the output designs have been compared objectively with the aid of several image similarity evaluation schemes including the SSIM, and FSIM Index methods.