• Title/Summary/Keyword: attraction model

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An Optimization of Dynamic Elements for Eddy Current Braking System of High Speed Train (고속전철의 와전류 제동장치 동적 최적화 연구)

  • Park, Chan-Kyoung
    • Proceedings of the KSME Conference
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    • 2001.06c
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    • pp.345-350
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    • 2001
  • Dynamic behavior of high speed train is very important because the high speed train should be safe and satisfied with the ride comfort. An eddy current brake system is mounted on trailer bogie and wheelset. The eddy current braking force longitudinally exerts on the articulated trailer bogie and the attraction force vertically exerts on the wheelset. Because a frame of eddy current brake system is flexible, these forces generate the vertical vibration at middle point of the frame. Also, the vibration change the vertical clearance between an electromagnet and top of rail which affect the magnitude of braking and attracting forces. Therefore, the dynamic behavior of the eddy current braking system must be predicted for design the dynamic characteristic of its mounting system when normally operate on rail which have irregularity. Vampire program is used for prediction of the dynamic behavior of an eddy current braking system. Five design variables and five performance index are considered for optimization through D-optimal experimental design in this paper. Also model center is used to search the optimal point for sum of performance index with variational matric method.

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Six sigma Management as a new quality control method in construction industry (건설산업의 신 품질관리기법으로서의 6시그마$(\sigma)$경영 도입에 대한 고찰)

  • Ryu Ho-Dong;Han Seung-Hun
    • Proceedings of the Korean Institute Of Construction Engineering and Management
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    • autumn
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    • pp.311-315
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    • 2002
  • Six sigma management has obtained good results in manufacturing and service industry as a new innovation approach to improve the enterprise-wise quality processes. However, there are lacks of implementation cases in the construction industry and furthermore, a results from a few cases applied is not successful enough to draw an attraction against the six sigma method. The main goal of this paper is to provide a comparative study regarding the pre-requisite conditions for the application of six sigma to the construction industry. Then, it present a generic procedure model that can support the introduction of six sigma management. Finally, the model is verified through the case study and lessons learned form a case are presented.

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Development of Green-Tourism Potential Evaluation Method Considering Rural Amenity and Demand of Citizen (농촌어메니티 및 도시수요를 고려한 그린투어리즘 잠재력 평가기법 개발)

  • Bae, Seung-Jong
    • Journal of Korean Society of Rural Planning
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    • v.14 no.4
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    • pp.109-119
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    • 2008
  • The objectives of this study are to develop a green tourism potential evaluation method with rural amenity and demand of citizen. The new index which was named GPD(green tourism potential degree) is designed to propose the green tourism potential of rural areas using spatial analysis of geographic information system and spatial interaction of gravity model. And in order to evaluate the green tourism potential with supply side and demand side, two indices were defined; One is green tourism demand degree(GDD) which is developed to quantify a demand side potential by the analysis of urban population and urbanization index, and the other is green tourism attraction degree(GAD) which is developed to quantify a supply side potential by the analysis of rural amenity values using AHP algorithm, based on opinion of related experts. The developed method was applied to a part of Kyounggi province, Seoul and Incheon. All the study area's GAD, GDD and GPD were assessed and the proposed green tourism potential evaluation method could be used in developing rural development plans and green tourism policies considering spatial interaction with citizen and green tourism resources.

Foreign Direct Investment and Economic Growth in SAARC Countries

  • Erum, Naila;Hussain, Shahzad;Yousaf, Abida
    • The Journal of Asian Finance, Economics and Business
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    • v.3 no.4
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    • pp.57-66
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    • 2016
  • Foreign Direct Investment (FDI) plays a vital role in economic growth of the countries. The present study analyses the impact of the FDI on economic growth of South Asian Association of Regional Cooperation countries by using the pooled data for the period 1990-2014. Neo-classical production function has been used for analysis and getting stock-to-flow estimation, Taylor series approximation has applied. Fixed Effects Model has been used to investigate the impact of FDI, domestic capital, labour and government expenditures on economic growth. It is the evident from the results that both domestic investment and FDI have been a positive effect on economic growth. The study finds that the contribution of domestic private investment is more trustworthy than the contribution of FDI. Consequently, FDI loses its attraction as an engine of growth if the adverse balance of payment consequence of the resulting profit repatriating is also taken into account. The labour has positive and significant association with GDP. The effect of government expenditure is negligible on economic growth. The findings suggest that growth strategy cannot yield the long term benefits if it neglects investments on human capital.

The role of Patent on Foreign Direct Investment: Evidence in Vietnam

  • PHAM, Nga Thi;PHAM, Huong Thi Thu
    • Journal of Distribution Science
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    • v.18 no.6
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    • pp.77-82
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    • 2020
  • Purpose: In the period of international integration, how is the implementation of intellectual property regulation in developing countries? Do intellectual property rights help attract more Foreign direct investment (FDI)? This study aims to show the effect of intellectual property rights, reflect in the number of patent registered (Patent distribution into two components: Patent_residents and Patent_non-residents) on FDI attraction in Vietnam. Research design, data and methodology: Using Autoregressive distributed lag (ARDL) model for the data collected from 1990 to 2018 with EViews version 9 software. Conclusions: The results indicate that the number of patent protection has a positive effect on FDI in both short term and long term. In particular, only patent registration of foreign individuals and organizations has a significant positive effect on attracting FDI, while that of Vietnamese patents is not statistically significant. From the results of this study, we provide some recommendations to help attract FDI based on raising awareness of intellectual property rights: Increase international cooperation for innovation to learn and encourage patent; Improve the capac ity of inventing as well as the ability to register patents of Vietnamese people; Government agencies are tasked to support a nd review registration procedures; Encouraging patent registration based on the patent.

Flexural Characteristics of Model Composite Deck Fabricated with VARTM (진공성형 제작 모델 복합소재 바닥판의 실험적 휨 거동특성 분석)

  • Lee Sung-Woo
    • Journal of the Computational Structural Engineering Institute of Korea
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    • v.18 no.4 s.70
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    • pp.417-426
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    • 2005
  • Recent days composite bridge dock is gaining attraction due to many advantages such as light weight, high strength, corrosion resistance, and high durability. In this study, composite deck models of hat, box and triangular section type wore fabricated with VARTM Process. For these models, three point flexural tests wore carried out both in strong and weak axis. The experimental results were compared with each other to determine efficient section profile. It has been demonstrated that composite sandwich deck has strong potentials to be used as bridge deck in the new construction and rehabilitation works.

Simulation of EPPR Valve Flow Force Characteristic using CFD Analysis (CFD를 이용한 EPPR 밸브 유동력 특성 분석 및 시뮬레이션)

  • Yoon, Ju Ho;Youn, Jang Won;Son, Ho Yeon;Kim, Dang Ju;Ahn, Kyoung Kwan
    • Journal of Drive and Control
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    • v.14 no.1
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    • pp.14-22
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    • 2017
  • Flow force is the additional unbalanced force acting on the valve spool by fluid flow, excluding the static pressure force that is offset on the spool land wall at the same magnitude. When designing the valve spool, it is assumed that the same average value of static pressure is applied to the inlet and outlet spool land wall in one chamber. However, the high velocity of the fluid flow by the inlet or outlet metering orifice creates unbalanced pressure distribution and generates additional force in the opposite direction to that of the solenoid attraction force. This flow force has a negative effect on the control performance of the EPPR valve, which needs to develop uniform output pressure along the entire spool control range. In this study, we developed a 3D model of the EPPR valve and conducted flow force characteristic analysis using CFD S/W (ANSYS FLUENT). The alleviated flow force model was derived by adjusting the design parameters of the spool notch.

INTERPARTICLE POTENTIAL OF 10 NANOMETER TITANIUM NANOPARTICLES IN LIQUID SODIUM: THEORETICAL APPROACH

  • KIM, SOO JAE;PARK, GUNYEOP;PARK, HYUN SUN;KIM, MOO HWAN;BAEK, JEHYUN
    • Nuclear Engineering and Technology
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    • v.47 no.6
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    • pp.662-668
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    • 2015
  • A suspension of titanium nanoparticles (Ti NPs) in liquid sodium (Na) has been proposed as a method to mitigate the violent sodium-water reaction (SWR). The interparticle potential between Ti NPs in liquid Na may play a significant role in the agglomeration of NPs on the reaction surface and in the bulk liquid Na, since the potential contributes to a reduction in the long-term dispersion stability. For the effective control of the SWR with NPs, a physical understanding of the molecular dynamics of NPs in liquid Na is key. Therefore in this study, the nonretarded Van der Waals model and the solvation potential model are employed to analyze the interparticle potential. The ab initio calculation reveals that a strong repulsive force driven by the solvation potential exceeds the interparticle attraction and predicts the agglomeration energy required for two 10-nm Ti NPs to be $4{\times}10^{-17}J$. The collision theory suggests that Ti NPs can be effective suppressors of the SWR due to the high energy barrier that prevents significant agglomeration of Ti NPs in quiescent liquid Na.

Influence of TVD Schemes on the Spatial Accuracy of Turbulent Flows Around a Hull When Using Structured and Unstructured Grids (정렬 및 비정렬 격자를 이용한 선체 주위 유동에서 TVD 기법이 공간 정확도에 미치는 영향)

  • Sim, Min Gyeoung;Lee, Sang Bong
    • Journal of the Society of Naval Architects of Korea
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    • v.58 no.3
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    • pp.182-190
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    • 2021
  • Computational simulations of turbulent flows around a model ship have been performed to investigate an influence of TVD schemes on the accuracy of advective terms associated with ship resistances. Several TVD schemes including upwind, second-order upwind, vanLeer, and QUICK as well as a nonTVD linear scheme were studied by examining temporal and spatial characteristics of accuracy transition in adjacent cells to the hull. Even though vanLeer scheme was the most accurate among TVD schemes in both structured and unstructured grid systems, the ratio of accuracy switch from 2nd order to 1st order in vanLeer scheme was considerable compared with the 2nd order linear scheme. Also, the accuracy transition was observed to be overally scattered in the unstructured grid while the accuracy transition in the structured grid appeared relatively clustered. It concluded that TVD schemes had to be carefully used in computational simulations of turbulent flows around a model ship due to the loss of accuracy despite its attraction of numerical stability.

The Economic Value for the Post-use of the 2018 Pyeongchang Winter Olympics Facilities: Case of Alpine Stadium in Jeongseon (2018평창동계올림픽 시설 사후활용에 대한 경제적 가치: 정선군 알파인 경기장을 사례로)

  • Song, Woon-Gang;Lee, Hae-Jin;Yang, Hee-Won
    • Asia-Pacific Journal of Business
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    • v.11 no.2
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    • pp.235-244
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    • 2020
  • Purpose - This study estimated the value of the post-use of Alpine stadium in Jeongseon as a tourist attraction, which is one of the 2018 Pyeongchang Winter Olympics facilities, and identified determinant factors on the willingness to pay (WTP). Design/methodology/approach - A dichotomous-choice model of contingent valuation method (CVM) that is known for an effective tool was used to calculate the value. The questionnaire was conducted on 650 visitors to major tourist destinations in Jeongseon and 629 copies of the valid samples were analyzed. Findings - The results shows that determinate factors on the WTP are; suggestion cost, need (application of Ecotourism Program to the Restoration Process), agree(agree to Ecotourism Program in the Restoration Process) and age. Also, the WTP on the facility is 16,296 won per person. Research implications or Originality - This study estimates the value of the post-utilization of Alpine Stadium of the 2018 Pyeongchang Winter Olympics facilities, which have been experiencing conflict in recent years. For this reason, the findings of the paper will provide meaningful information for tourism development and management policies of the region.