• Title/Summary/Keyword: stages of change model

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EXAMINATION OF CALCULATION METHOD FOR THE FLEXURAL RIGIDITY OF CROP STALKS

  • Hirai, Yasumaru;Inoue, Eiji;Hashiguchi, Koichi;Kim, Young-Keun;Inaba, Shigeki;Tashiro, Katsumi
    • 한국농업기계학회:학술대회논문집
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    • 한국농업기계학회 2000년도 THE THIRD INTERNATIONAL CONFERENCE ON AGRICULTURAL MACHINERY ENGINEERING. V.II
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    • pp.287-294
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    • 2000
  • Calculation of the flexural rigidity value (EI) is indispensable for prescription of deflection characteristics of crop stalks in harvesting□Conventionally□EI has been determined by either average EI of the whole stalk or average EI of each stems divided into node through the calculation method of cantilever with homogeneous section□However□deflection characteristics of crop stalks caused by mechanical operation such as combine harvester were not exactly presumed by these conventional EI through the experiment by authors. Further, actual EI of a stalk changes in company with a change of moisture contents as time passes during the experiment. Finally, efficient calculation method for determining EI is needed in order to improve these problems. In this study, mechanical model based on actual structure of the crop stalk with variety sectional area was proposed. This mechanical model is calculated by the theory of cantilever with continuous stages. Therefore, improvement of both calculating accuracy on EI and efficiency of measuring system was tried. At first, this calculation method was applied to piano wire of which EI was recognized in advance. As a result, EI calculated from this new method coincided approximately with piano wire's EI. Next, applying to crop stalks as same as piano wire, relationship between loads acting on crop stalks and deflection values calculated by EI using this new calculation method was exactly presumed in comparison with conventional method. Further, measuring time of deflection test was greatly reduced. Finally, new calculation method of EI will be available for estimating mechanical characteristics of so many kinds of crop stalks in harvesting operation. Further, in this study, new deflection test using image-processing apparatus by computer will be introduced.

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중학생들의 건강증진행위, 삶의 질에 대한 구조모형 (Structure Model for Health Promotion and Service Quality of Life of Middle School Students)

  • 이성호
    • 대한통합의학회지
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    • 제8권4호
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    • pp.203-212
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    • 2020
  • Purpose : Middle school students in the early stages of adolescents need balanced growth and development, and they are in the process of forming healthy lifestyles and are in an important period when they need to lay the foundation for a healthy life through active health management and guidance. Through systematic health-related policies and education, I intend to lay the groundwork for them to form healthy lifestyles in their high schools and adulthood. Methods : For this study, a survey was conducted from September 1 to October 30, 2019, and 300 middle school students based in Busan Metropolitan City were surveyed. Based on the analysis and results of preceding studies, a research model was set up to find out the effect of family support, health control activities and self-efficacy on health promoting behaviors and how health promoting behaviors affect the quality of life. Results : First, if family support is high, health promotion behavior and quality of life are analyzed to be high, so family support is affecting health promotion behavior and quality of life. Second, health control behavior had a significant effect on health promotion behavior, but did not affect the quality of life. Third, self-efficacy was having a significant effect on health promotion behavior and quality of life. Fourth, health promotion behavior was affecting the quality of life. Conclusion : In order to improve the quality of life, middle school students should first increase their health promotion behavior, and it is important to be supported by their family members and strengthen their self-efficacy as variables that increase their health promotion behavior. First of all, they should be given the infinite trust of the family and the strong belief that the family always supports them, and based on this, the student himself will be able to strengthen his or her self-efficacy. In addition, the process of physical and mental change of students comes to everyone, but during this process, members of society, such as families and schools, should send them support and trust so that they can grow up to be the decent members of society.

경제자유화가 외국인직접투자 유치에 미치는 영향 (The Effect of Economic Liberalization on Foreign Direct Investment)

  • 김남수
    • 아태비즈니스연구
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    • 제12권4호
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    • pp.289-297
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    • 2021
  • Purpose - This study analyzed the correlation between economic liberalization and foreign direct investment. The purpose of this study is to seek ways to attract foreign direct investment from developing countries. Design/methodology/approach - This study analysed with observations of 19 from 2000 to 2018 using a fixed effect model, a random effect model, and a two-way fixed effect model. Findings - First, it was found that economic liberalization had a positive effect on attracting foreign direct investment in the early stages of economic liberalization. Second, it was found that economic liberalization in the deepening stage of economic liberalization had a negative effect on attracting foreign direct investment. In general, it was found that the higher the level of economic liberalization in developing countries is not accompanied by innovative changes in the industrial structure, the higher the level of economic liberalization is likely to decrease the inducement of foreign direct investment due to negative factors such as an increase in labor costs. Overall, this study approved that Economic liberalization have a non-linear (inverted U-shape) relationship with the inflow of foreign direct investment. Research implications or Originality - First, this study attempted to expand the variables for the determinants of FDI by analyzing economic factors which is a determinent of FDI. Second, economic liberalization generally has a positive effect on foreign direct investment, but it proved that it does not have only positive effects as a factor of attracting foreign direct investment in developing countries. The advantage of low wages in ASEAN countries acts as a factor for foreign direct investment, but as the degree of economic liberalization increases, the environment such as government size, guarantee of property rights, international trade freedom, fiscal soundness, and regulations change positively. On the other hand, it can be suggested that if the industrial level is less, it may lead to a loss of comparative advantage and a decrease in investment.

다문화청소년의 트라우마 중재를 위한 가상현실 프로그램 모형 (Virtual Reality Program Model for Trauma Intervention in Multi-cultural Adolescents)

  • 김경숙;송은지;김민경;주세진;김민정
    • 한국정보통신학회논문지
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    • 제21권2호
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    • pp.361-366
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    • 2017
  • 최근 가상현실의 기술이 발달함에 따라 게임중독, 알코올 중독 등에 대한 가상현실 치료 프로그램이 개발되고 있다. 본 연구는 다문화 청소년의 트라우마 중재를 하기 위하여 가상현실에 기반한 인지행동치료 프로그램을 구현하는 개발과정의 모형을 제시하고자 한다. 인지행동치료의 가상현실 프로그램개발은 크게 3단계로 나누어진다. 제1단계에서는 다문화청소년이 트라우마로 인하여 경험한 주요 감정과 표출된 문제를 포함한 트라우마의 특성들을 파악하고 제2단계에서는 트라우마에 대한 인지행동치료를 목표로 한 시나리오를 구성의 전개과정과 범위의 내용을 제시되어야 한다. 최종 제3단계서는 시나리오 콘텐츠의 가상현실프로그램 구현에 대한 타당성 검토를 통해 다문화청소년의 긍정적 변화를 이끌 수 있는 중재 프로그램 개발의 가능성을 제안하였다.

Land Use Feature Extraction and Sprawl Development Prediction from Quickbird Satellite Imagery Using Dempster-Shafer and Land Transformation Model

  • Saharkhiz, Maryam Adel;Pradhan, Biswajeet;Rizeei, Hossein Mojaddadi;Jung, Hyung-Sup
    • 대한원격탐사학회지
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    • 제36권1호
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    • pp.15-27
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    • 2020
  • Accurate knowledge of land use/land cover (LULC) features and their relative changes over upon the time are essential for sustainable urban management. Urban sprawl growth has been always also a worldwide concern that needs to carefully monitor particularly in a developing country where unplanned building constriction has been expanding at a high rate. Recently, remotely sensed imageries with a very high spatial/spectral resolution and state of the art machine learning approaches sent the urban classification and growth monitoring to a higher level. In this research, we classified the Quickbird satellite imagery by object-based image analysis of Dempster-Shafer (OBIA-DS) for the years of 2002 and 2015 at Karbala-Iraq. The real LULC changes including, residential sprawl expansion, amongst these years, were identified via change detection procedure. In accordance with extracted features of LULC and detected trend of urban pattern, the future LULC dynamic was simulated by using land transformation model (LTM) in geospatial information system (GIS) platform. Both classification and prediction stages were successfully validated using ground control points (GCPs) through accuracy assessment metric of Kappa coefficient that indicated 0.87 and 0.91 for 2002 and 2015 classification as well as 0.79 for prediction part. Detail results revealed a substantial growth in building over fifteen years that mostly replaced by agriculture and orchard field. The prediction scenario of LULC sprawl development for 2030 revealed a substantial decline in green and agriculture land as well as an extensive increment in build-up area especially at the countryside of the city without following the residential pattern standard. The proposed method helps urban decision-makers to identify the detail temporal-spatial growth pattern of highly populated cities like Karbala. Additionally, the results of this study can be considered as a probable future map in order to design enough future social services and amenities for the local inhabitants.

열교차단장치가 적용된 철근 콘크리트 슬래브의 휨거동 예측을 위한 해석모델 (Analytical Models for the Prediction of the Flexural Behavior for Thermal Bridge Breaker Systems embedded in Reinforced Concrete Slabs)

  • 신동현;김형준
    • 한국전산구조공학회논문집
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    • 제28권3호
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    • pp.325-333
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    • 2015
  • 최근들어 철근콘크리트 슬래브와 벽의 연결부에 적용 가능한 열교차단장치에 대한 연구가 다수 수행되고 있다. 이에 본 연구에서는 열교차단장치가 적용된 슬래브의 균열 전 탄성거동, 균열 후 항복거동 및 극한강도까지 적용이 가능한 해석모델을 제안하고, 실험결과와의 비교를 통하여 제안 모델의 정확도를 검증하고자 하였다. 해석모델은 변형률 적합조건과 힘의 평형개념을 적용하였으며, 이 때 구성 재료의 응력-변형률 관계는 재료실험 결과를 적용하였다. 해석모델의 신뢰성 검증을 위해 모멘트-곡률 관계, 하중단계에 따른 중립축을 실험결과와 비교하였으며, 제안된 해석모델은 실험결과로 획득한 전체적인 휨거동 양상과 거의 일치함을 확인할 수 있었다.

MES 효율 향상을 위한 참조정보 일괄 적용 모델 (Reference Information Batch Application Model for Improving the Efficiency of MES)

  • 박상혁;박구락;김동현;정경록
    • 한국융합학회논문지
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    • 제12권10호
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    • pp.71-79
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    • 2021
  • 제조업 분야에서는 경쟁력 강화를 위하여 다품종 생산으로의 전환이 이루어지고 있으며, 하이브리드 제조기술이 증가하고 있다. 특히 제조실행시스템과 ERP 등의 도입을 통하여 생산 품질 향상에 많은 노력을 기울이고 있기에, 신속하고 효과적인 관리를 위한 MES 운영이 필요하다. MES는 제품 생산과 관련된 모든 단계를 관리하면서, 생산 활동에 비효율적인 부분은 개선하고, 공정 변경의 경우에 시스템에 변경 사항을 반영해야 한다. 그러나 대부분의 MES는 시스템 관리자를 통하여 수동적이고, 반복적으로 비효율적인 작업을 계속 하고 있는 상황이다. 본 논문에서는 생산과 관련된 요구사항을 시스템 관리자가 특정 라인의 장비에 대한 참조 정보를, 다른 라인의 동일한 장비에도 일괄 적용할 수 있는 모델을 제안한다. 제안 모델을 통하여 참조 정보의 일괄 적용과 선택 적용의 구분으로 생산 라인에 대한 유연한 대처가 가능할 것으로 기대된다.

시추공간 전기비저항 토모그래피를 이용한 $CO_2$ 주입 모니터링 (Monitoring $CO_2$ injection with cross-hole electrical resistivity tomography)

  • Christensen, N.B.;Sherlock, D.;Dodds, K.
    • 지구물리와물리탐사
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    • 제9권1호
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    • pp.44-49
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    • 2006
  • 이 연구에서는 $CO_2$ 주입 모니터링에서의 전기비저항 토모그래피(ERT)의 분해능에 대해 조사한다. $CO_2$ 주입체 양쪽의 케이싱 없는 시추공에서 단극자 및 양극자 전극 배열이 사용된다. 주입 전 및 주입에 따른 3단계 모델에 대한 반응이 계산되고, 잡음이 더해진 후의 이론 값들이 L1 과 L2 norm을 사용해 역산된다. 역산결과는 어느 정도 수준이상의 $CO_2$ 부피가 확실히 감지됨을 보여준다. 대부분의 경우에 L1 norm의 경우가 L2에 비해 우월함이 판명되었다. 역산 결과를 주입 전 모델의 역산결과로 정규화하면 전기비저항이 변화하는 부분의 훌륭한 영상을 보여주며, 비저항의 전체적인 변화를 통합해서 판단하면 전체 주입된 부피에 대한 타당한 측정이 이루어짐이 입증된다.

FE TECHNIQUES TO IMPROVE PREDICTION ACCURACY OF DIMENSION FOR COLD FORGED PART

  • Lee Y.S.;Lee J.H.;Kwon Y.N.;Ishikawa T.
    • 한국소성가공학회:학술대회논문집
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    • 한국소성가공학회 2003년도 The 8th Asian Symposium on Precision Forging ASPF
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    • pp.26-30
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    • 2003
  • Since the dimension of cold forged part is larger than the cavity size of forging die, the difference results from the various features, such as, the elastic characteristics of die and workpiece, thermal influences, and machine-elasticity. All of these factors should be considered to get more accurate prediction of the dimension of forged part. In this paper, severe FE techniques are proposed to improve the prediction accuracy of dimension for cold forged part. To validate the importance of the above mentioned factors, and the estimated results are compared with the experimental results. The used model is a closed die upsetting of cylindrical billet. The calculated dimensions are well coincided with .the measured values based on the proposed techniques. The proposed techniques have put two simple but important points into Fe simulation. One is the separation of forging stages into 3 steps, from a loading through punch retraction to ejecting stage. The other is the dimensional change, according to the temperature changes due to the deformation. The FE analysis could predict the dimension of cold forged part within the $10{\mu}m$, based on the more realistic consideration.

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System identification of the suspension tower of Runyang Bridge based on ambient vibration tests

  • Li, Zhijun;Feng, Dongming;Feng, Maria Q.;Xu, Xiuli
    • Smart Structures and Systems
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    • 제19권5호
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    • pp.523-538
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    • 2017
  • A series of field vibration tests are conducted on the Runyang Suspension Bridge during both the construction and operational stages. The purpose of this study is devoted to the analysis of the dynamic characteristics of the suspension tower. After the tower was erected, an array of accelerometers was deployed to study the evolution of its modal parameters during the construction process. Dynamic tests were first performed under the freestanding tower condition and then under the tower-cable condition after the superstructure was installed. Based on the identified modal parameters, the effect of the pile-soil-structure interaction on dynamic characteristics of the suspension tower is investigated. Moreover, the stiffness of the pile foundation is successfully identified using a probabilistic finite model updating method. Furthermore, challenges of identifying the dynamic properties of the tower from the coupled responses of the tower-cable system are discussed in detail. It's found that compared with the identified results from the freestanding tower, the longitudinal and torsional natural frequencies of the tower in the tower-cable system have changed significantly, while the lateral mode frequencies change slightly. The identified modal results from measurements by the structural health monitoring system further confirmed that the vibrations of the bridge subsystems (i.e., the tower, the suspended deck and the main cable) are strongly coupled with one another.