• Title/Summary/Keyword: Conceptual Study

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Validation on Conceptual Design and Performance Analyses for Compound Rotorcrafts Considering Lift-offset

  • Go, Jeong-In;Park, Jae-Sang;Choi, Jong-Soo
    • International Journal of Aeronautical and Space Sciences
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    • v.18 no.1
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    • pp.154-164
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    • 2017
  • This work conducts a validation study for the XH-59A helicopter using a rigid coaxial rotor system in order to establish the techniques of the conceptual design and performance analysis for the lift-offset compound rotorcraft. As a tool for conceptual design and performance analysis, NDARC (NASA Design and Analysis of Rotorcraft) is used for the present study. An assumed mission profile is considered for the conceptual design of the XH-59A. As a validation result of the design, the dimensions and weight of the XH-59A are appropriately designed when compared to the target values since the relative error is less than 0.5%. Then, performance analyses are conducted for the designed XH-59A model with and without auxiliary propulsion in hover and forward flight conditions. The present analyses show good validity since the prediction results compare well with both the flight test and previous analyses. Therefore, the techniques for the conceptual design and performance analysis of the lift-offset compound helicopter are overall considered to be appropriately established. In addition, this study investigates the influence of the lift-offset on the rotor effective lift-to-drag ratio of the XH-59A helicopter with auxiliary propulsion. As a result, the improvement of the rotor effective lift-to-drag ratio can be obtained by appropriately increasing the lift-offset in high-speed flight.

Inductive Influence of Algorithmic and Conceptual Problems (수리 문제와 개념 문제 사이의 유도 효과)

  • Noh, Tae-Hee;Kang, Hun-Sik;Jeon, Kyung-Moon
    • Journal of The Korean Association For Science Education
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    • v.24 no.2
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    • pp.320-326
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    • 2004
  • This study investigated whether algorithmic problem solving and conceptual problem solving influenced each other or not. Four classes of 12th grade (N= 112) that are equal in prior achievement were randomly assigned to group AC (Algorithmic-Conceptual problem) and group CA (Conceptual-Algorithmic problem). Students of group AC solved the conceptual problems after learning the related algorithmic problems, and those of group CA solved the same problems in reverse order. The results revealed that learning the algorithmic problems improved students' ability to solve the related conceptual problems, but learning the conceptual problems did not help students solve the related algorithmic problems. Regarding the confidence on problem solving, learning the algorithmic problems had little effect on the related conceptual problems. Learning the conceptual problems also had little effect on students' confidence on solving of the related algorithmic problems.

A Study on the process for Managing the Reliability of Conceptual cost estimates in Building Projects (건축 프로젝트 개산견적 신뢰도 관리 프로세스에 관한 연구)

  • An, Sung-Hoon;Kim, Dae-Won;Park, U-Yeol
    • Journal of the Korea Institute of Building Construction
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    • v.10 no.2
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    • pp.133-138
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    • 2010
  • Conceptual cost is estimated with insufficient information at an early stage of a building construction project, resulting in an inevitable gap between conceptual estimated cost and real constructed cost. For a project to be successful, this gap must be managed to be lower than a reliable level. Therefore, the purpose of this study is to propose a structural process for managing the reliability of conceptual cost estimates at an early stage of a building construction project. In researching this study, conceptual cost estimate experts were interviewed,and a risk management process was studied. Reliability assessment and a review process for improving the quality of conceptual cost estimate and the planning strategy of reliability management based on previous similar projects were added to the present estimate process. The proposed reliability management process will improve the chances of a successful project, by helping to decrease the risk of conceptual estimated cost.

Development of the Selection of Optimal Conceptual Design for the Noise-reduced Aluminum System Form

  • Hong, Jong Hyun;Yeom, Dong Jun;Seo, Jung Hoon;Kim, Young Suk
    • International conference on construction engineering and project management
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    • 2015.10a
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    • pp.708-709
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    • 2015
  • In Korea, a series of noise-reduced aluminum forms are being recently used in apartment housing construction. However, their complicated and time-consuming work processes, and the noise which is still generated due to the inherent property of aluminum when especially installing and dismantling them are have been pointed out as a problem to be certainly solved for increasing their practical use in construction sites. The primary objectives of this study are to propose a conceptual design of a newly designed noise-reduced aluminum form in which the noise can be enormously decreased during form works. The conceptual design in this study improved problems of conventional system aluminum forms, and, later, a system aluminum form developed based on this conceptual design will be able to ensure noise-reduction and safety as well as excellent applicability.

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Conceptual Meaning of Purple-series Color Names in the Clothing of Joseon Dynasty Period (조선시대 복식에 나타난 자색계 색명의 개념적 의미)

  • 김순영;남윤자;조우현
    • Journal of the Korean Society of Clothing and Textiles
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    • v.28 no.11
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    • pp.1458-1469
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    • 2004
  • In this study, color names focusing on the purple series, appearing in the clothing of the Joseon Dynasty, were classified systematically, and the conceptual meaning of each name were investigated through various methods. The results are as follows; First, the color names of purple-series were classified systematically. According to the integration scheme of morphemes, color names could be divided into two categories; single names and composite names. Color names could also be classified into universal and limited names according to the areal distribution of literatures. Secondly, the conceptual meaning of the color names of purple-series were considered. The conceptual meaning could be divided into two categories; one 'etymological and dyeing methodological meaning', the other 'color systematic meaning' By studying the dictionary definition of color names, comparing and analyzing the material composition of colors, the etymological and dyeing methodological meaning could be grasped. Furthermore, the color systematic meaning of each name could be grasped through the cluster analysis of L*, a*, b* values measured from the relics of clothing. Thirdly, the conceptual semantic structure were established on the basis of conceptual meanings of purple-series color names. The conceptual semantic structure of purple-series color names is forming discrete structure with the dyeing method and material of dyes as their semantic components.

Conceptual Design of a Ground Launcher System, Using ICDM - Integrated, Customer Driven, Conceptual Design Method (통합개념설계 방법론을 이용한 지상 발사장비 개념설계 연구)

  • Lee, Jae-Ryul;Park, Young-Won
    • Journal of the Korea Institute of Military Science and Technology
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    • v.9 no.3
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    • pp.56-65
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    • 2006
  • It is well known and widely accepted that the conceptual design is the most influential step in the design process of a product or a system and that about 75% of the life cycle cost is committed as the results of this stage. The purpose of this paper is to present and demonstrate the step of ICDM(Integrated, Customer Driven, Conceptual Design Method) for the development of a ground launcher system, TEL(Transporter, Erector and Launcher). The results of the study show the effectiveness of the method during the conceptual design phase of new complex systems or high-tech products.

Modeling in System Engineering: Conceptual Time Representation

  • Al-Fedaghi, Sabah
    • International Journal of Computer Science & Network Security
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    • v.21 no.3
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    • pp.153-164
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    • 2021
  • The increasing importance of such fields as embedded systems, pervasive computing, and hybrid systems control is increasing attention to the time-dependent aspects of system modeling. In this paper, we focus on modeling conceptual time. Conceptual time is time represented in conceptual modeling, where the notion of time does not always play a major role. Time modeling in computing is far from exhibiting a unified and comprehensive framework, and is often handled in an ad hoc manner. This paper contributes to the establishment of a broader understanding of time in conceptual modeling based on a software and system engineering model denoted thinging machine (TM). TM modeling is founded on a one-category ontology called a thimac (thing/machine) that is used to elaborate the design and analysis of ontological presumptions. The issue under study is a sample of abstract modeling domains as exemplified by time. The goal is to provide better understanding of the TM model by supplementing it with a conceptualization of time aspects. The results reveal new characteristics of time and related notions such as space, events, and system behavior.

A Study on the Conceptual Metaphor of English mind and Korean maum

  • Jhee, In-Young
    • Lingua Humanitatis
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    • v.8
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    • pp.409-427
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    • 2006
  • This paper deals with the various conceptual metaphors of 'mind' in Korean and English within the Cognitive Semantics. The purpose of this paper is to investigate the metaphorical expressions of the concept 'mind' represented andunderstood in various ways in Korean and English, to find out the linguistically-universal conceptual metaphors underlying the uses of the metaphoric expressions. In addition, this paper discusses the differences in linguistic realization of the concept 'mind' between Korean and English from the socio-cultural background. In the traditional view, metaphor was thought only as the linguistic matters and a deviance from literal or normal use. However, within the Cognitive Linguistic view such as Lakoff and Johnson(1980), metaphor has been considered as a means of understanding and conceptualizing world. According to them, metaphor is found in everyday life because it is not only as a matter of language but also as a nature of human conceptual system controlling cognition, thought and behavior. Conceptual metaphor is suggested as a device to understood abstract and less familiar things through concrete and more familiar things. Conceptual metaphors may be realized linguistically as well as non-linguistically, in the form of movies, arts or behavior. To define the concept 'mind' shared among the Koreans, conceptual metaphors used to represent 'maum(mind)'in Korean are examined. Then they are compared with the ones used to represent 'mind' in English. This is based on the idea that conceptual metaphors represented in linguistic expressions naturally reflect the speakers' concept and conceptualization is a universal irrespective of language. This paper exemplifies the Korean sentences as well as English sentences to utilize some conceptual metaphor such as Johnson(1987)'s THE MIND IS THE BODY and shows many other conceptual metaphors used in Korean and English to represent the same concept 'mind'. What are some metaphors shared by two languages and what is specific to one of them will be shown, too. This paper also suggests that the different conceptualization or lexicalization is partly due to the effect of the oriental cultural background that is more interested in the mental world than the physical world.

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A study on the conceptual design of oceanographic buoy systems (해양 관측용 부이의 개념 설계 연구)

  • 조규남;이우섭
    • Journal of Ocean Engineering and Technology
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    • v.11 no.4
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    • pp.205-212
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    • 1997
  • The major subject of this paper is the conceptual design of a cable-buoy system based on mechanics of floating bodies and mooring lines. The goal is to present a systematic relevant analysis procedure for the conceptual design of oceanographic buoy systems. The dynamics of a free floating body with an anchoring line is studied and a model is proposed through the primary engineering.

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Developing the Course of Cornerstone Design Concentrating on Conceptual Design (개념설계에 치중하는 기초설계 과목 개발)

  • Kwon, Sunggyu
    • Journal of Engineering Education Research
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    • v.22 no.2
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    • pp.16-27
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    • 2019
  • In order to note some points necessary for developing the cornerstone design course concentrating on conceptual design through that students acknowledge that engineering design is not to make things but to produce knowledge not only meet requirements of clients, users, and stake holders but also to solve problems, this paper describes the contents for the course that covers conceptual design as well as embodiment design, explains some ways and tools both for guiding students and for asking for study of lecture materials, and discuss things to be considered when faculty designs the course.