• Title/Summary/Keyword: a conceptual model

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A Method of Simulating Ephemeral Stream Runoff Characteristics in Cheonmi-cheon Watershed, Jeju Island (제주 천미천 유역의 간헐하천 유출특성 모의 방안)

  • Kim, Nam-Won;Chung, Il-Moon;Na, Hanna
    • Journal of Environmental Science International
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    • v.22 no.5
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    • pp.523-531
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    • 2013
  • In this study, a method of simulating ephemeral stream runoff characteristics in Jeju watershed is newly suggested. The process based conceptual-physical scheme is established based on the SWAT-K and applied to Cheonmi-cheon watershed which shows the typical pattern of ephemeral stream runoff characteristics. For the proper simulation of this runoff, the intermediate flow and baseflow are controlled to make downward percolation should be dominant. The result showed that surface runoff simulated by using the modified scheme showed good agreement with observed runoff data. In addition, it was found that the estimated runoff directly affected the groundwater recharge rate. This conceptual model should be continuously progressed including rainfall interception, spatially estimated evapotranspiration and so forth for the reasonable simulation of the hydrologic characteristics in Jeju island.

Development of a Friction Tester and Experimental Study on the Frictional Characteristics of Rubbers (고무류의 마찰시험기 개발 및 마찰특성에 관한 실험적연구)

  • 천길정;오성모;이동환;이봉구;김완두
    • Tribology and Lubricants
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    • v.15 no.2
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    • pp.193-198
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    • 1999
  • Applying design methodology, new type friction tester has been developed. Functional analysis has been executed and functional structure were constructed during the conceptual design. Optimal solution has been selected and a proto model has been manufactured according to the conceptual design. Using the tester developed in the laboratory, frictional characteristics of natural rubbers have been experimentally analyzed. Friction coefficient has been calculated from the measured normal force and friction force under various speeds, loads, and temperatures. The corelations between the various operating conditions and friction coefficients have been verified. Especially, drag friction due to the visco-elastic behavior of the rubber has been observed in this analysis.

Analysis of Time-Driven ABC in Container Terminal (컨테이너터미널에서의 시간-동인활동기준원가의 분석)

  • Lee, Chae Min;Shin, Jae Yeong
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • 2014.10a
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    • pp.7-8
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    • 2014
  • One of the important factor for port selection is total handling charge(THC) of container terminal, and consequence of that the actual cost is vital for variation of THC. However, a great majority of the reported ABC applications have been limited to manufacturing and a little has been written on how the ABC approach can be used for logistics company especially for container terminal. This study proposes the applicable conceptual framework and cost management model based on Time-Driven Activity-Based Costing for container terminal.

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Conceptual design of light bascule bridge

  • Xu, Weiwei;Ding, Hanshan;Lu, Zhitao
    • Structural Engineering and Mechanics
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    • v.29 no.4
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    • pp.381-390
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    • 2008
  • This paper proposed a conceptual design of bascule bridge, which is a new kind of movable bridge with an aim of reducing the weight of superstructure. Compared with the traditional bascule bridge, the light bascule bridge chooses cable-stayed bridge with inclined pylon as its superstructure; therefore, the functions of balance-weight and structure will fuse into one. Otherwise, it adopts moving counterweight to adjust its center of gravity (CG) to open or close the bridge. In order to lighten the superstructure, it uses contact springs to auxiliary retract, and intelligent prestressing system (IPS) to control the main girder's deformation. Simultaneously the vibration control scheme of structure is discussed. Starting from establishing the mechanical model of bridge, this article tries to analyze the conditions that the design parameters of structure and attachments should satisfy to. After the design procedure was presented, an example was also adopted to explain the primary design process of this kind bridge.

Object-oriented Simulation Modeling for Service Supply Chain (서비스 공급사슬을 위한 객체지향 시뮬레이션 모델링)

  • Moon, Jong-Hyuk;Lee, Young-Hae;Cho, Dong-Won
    • Journal of the Korea Society for Simulation
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    • v.21 no.1
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    • pp.55-68
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    • 2012
  • Recently it is important to understand service supply chain because the economy moves from manufacturing to services. However, most of existing supply chain research focuses exclusively on the manufacturing sector. To overcome this situation, it needs to investigate and analyze service supply chain. Simulation is one of the most frequently used techniques for analysis and design of complex system. Service supply chain is complex and large systems that require an accurate designing phase. Especially, it is important to examine closely the dynamically interactive behavior of the different service supply chain components in order to predict the performance of the servcie supply chain. In this paper, we develop a conceptual model of service supply chain. Then, we present a new procedure to develop simulation model for the developed conceptual model of service supply chain, based on the UML analysis and design tools and on the ARENA simulation language. The two main characteristics of the proposed procedure are the definition of a systematic procedure to design service supply chain and of a set of rules for the conceptual model translation in an ARENA simulation language. The goal is to improve the knowledge on service supply chain management and support the simulation model development efficiency on service supply chain.

Effect of Cooperative Learning on Conceptual Change of Atmospheric and Water Cycle (대기와 물의 순환 개념변화에 대한 협동학습의 효과)

  • Jeong, Jin-Woo;Jang, Myoung-Duk;Chun, Seon-Lye
    • Journal of the Korean earth science society
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    • v.25 no.2
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    • pp.63-73
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    • 2004
  • This study investigated the effect of cooperative learning on the middle school students’ conceptual change of atmospheric and water cycle and also examined the verbal interaction patterns in a cooperative group. The study also analyzed the relationship between the verbal interaction and students’ conceptual change in the cooperative learning situation. Two classes from a middle school were selected as an experimental group (cooperative learning group, n = 37) and a control group (traditional learning group, n = 37), respectively. The experimental group was taught by STAD cooperative learning model and received collaborative skill training. The results of the study can be summarized as follows: first, there were no significant differences in conceptual change between the two groups. As for the middle-achieving students on the pretest, however, the score of the cooperative learning group was significantly higher than that of the traditional learning group. Secondly, verbal interaction in the cooperative learning situation mainly happened among high- and middle achieving students. In addition, the students who were successful in undergoing conceptual change had more frequent verbal interactions than the students who were not. The study suggests that it is more important to interact between a teacher and students than to interact between the students and students in order to correct students’ misconception.

Fire Power Analysis for Concept Exploration of Combat Vehicle (전투차량체계의 개념탐색을 위한 화력성능분석)

  • Lim, O-Kaung;Choi, Eun-Ho;Ryoo, Jae-Bong
    • Journal of the Computational Structural Engineering Institute of Korea
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    • v.22 no.3
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    • pp.251-258
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    • 2009
  • At the stage conceptual design, combat vehicle is classified into three general categories of fire power, mobility and physical properties of system. The present research is restricted to fire power and its optimization. At the stage of conceptual designing of system, it is appropriate to consider major variables affecting fire power - including the weight of bullet, which exerts a direct influence on destroying effect, maximum range which takes long range firing in consideration. To estimate the maximum firing range, a simple interior ballistic and an exterior ballistic model were built by using the lumped parameter method, Le Duc method and point mass trajectory model. Design of experiment and regression analysis was used to derive simulations of fire power. Finally, response surface models were built and design variables were analyzed.

A Study on Conceptual Design and Dynamic Model of Roller Rig for Maintenances with Maximum Speed of 350km/h (350km/h 급의 유지보수용 주행시험기의 개념설계 및 동적모델 제시 연구)

  • Goo, Jun-Sung;Ryu, Bong-Jo;Lee, Dae-Bong;Lee, Eun-Gyu;Shin, Kwang-Bok
    • Proceedings of the KSR Conference
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    • 2007.11a
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    • pp.296-300
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    • 2007
  • Roller rigs have been built widely to study and evaluate the dynamic behaviors of railway vehicles, and they have particularly been applied to the development and routine maintenance of high-speed trains. However, there is no roller rig for routine maintenances of high speed train in Korea, although high speed train is running on the lines. Therefore, it is very important issue to check and evaluate the dynamic responses of high speed train after several years of operation. This paper presents a study on the conceptual design and dynamic model to develop the roller rig for the routine maintenances of high speed trains. The roller rig has two independent electronic motor and maximum speed of 350km/h, which can simulate running on straight and curved track. CATIA V5 was used to design the 3D geometrical models and ADAMS was used to verify and analyze the dynamic behaviors of roller rig.

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Conceptual Development of Workplace Bullying: Focusing on Hospital Nurses (직장 내 괴롭힘 개념 개발: 병원간호사를 중심으로)

  • Lee, Younju;Lee, Eun Jin
    • Korean Journal of Health Education and Promotion
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    • v.31 no.1
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    • pp.57-70
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    • 2014
  • Objectives: The purpose of this study was to build a conceptual framework of bullying in nursing workplace. Methods: A comprehensive literature review was conducted to identify concepts in relation to bullying in nursing workplace by searching research articles published between 1995 and 2013. In-depth interviews were performed with 14 nurses who experienced bullying at work. The Hybrid Model was applied for concept analysis which led to identify attributes of bullying in nursing workplace. Results: The antecedents of bullying in nursing workplace were offenders, victims, and administrators. They create negative effects on organizational culture and imbalance of power between authority and subordinate workers in the organization. Bullying in nursing workplace that occurred in the forms of inefficient organizational culture, imbalance of power, and the vulnerability of individual or individuals and groups of individuals formed an unstable dynamic. It is expressed as verbal and nonverbal bullying, work-related bullying, and external threats. Consequently, workplace bullying causes physical and psychological withdrawal and increased negative energy in an organization. Conclusions: Workplace bullying consisted of verbal abuse, alienation, unreasonable work processes, restriction on work-related rights, and external threat.

A Study on Home-Based Work: The Chracteristics and Practices of Home-Based Work in the United States and The Conceptual Model for Studying on At-Home Income Generation (재택근무 가정의 실태 및 개념적 모델에 관한 연구)

  • 문숙재
    • Journal of the Korean Home Economics Association
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    • v.36 no.3
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    • pp.207-224
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    • 1998
  • This study is approach to the Home-Based Work. More specifically, to examine about the families who try to combined home life and income-generation work under the same roof. Families were looking at Home-Based Work as one solution to the work-family crunch. Many research papers have suggested that Home-Based Work provides an effective way to balance the demands of paid employment and family responsibilities. Therefore, this proposed research reviewed the Home-Based Work as they contributed to individual and family satisfactions. The Prupose of this paper is to address issues related to Home-Based Work from the perspective of theory and application in family resource management, also to suggest a conceptual model for family work activities is advanced. This paper is examined concepts related to Home-Based Work employment that could be used to frame and describe the empirical study are specified. This paper was informed by analyses of data from project NE-167. "At-Home Income Generation: Impact on Management, Productivity, and Stability in Rural/Urban Families". The results from this paper will be helpful in enhancing the stability and satisfaction of families who worked in Home-Based Work.ased Work.

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