• 제목/요약/키워드: Dimensional nature

검색결과 371건 처리시간 0.025초

자동차 에어컨용 전곡형 원심 송풍기의 공력성능 분석 (Experimental Study on the Performance of a Forward-Curved Centrifugal Fan for an Automotive Air-Conditioner)

  • 권의용;조남효
    • 유체기계공업학회:학술대회논문집
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    • 유체기계공업학회 2000년도 유체기계 연구개발 발표회 논문집
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    • pp.122-128
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    • 2000
  • Aerodynamic optimization of an automotive air-conditioning blower is a hard task because of the highly complex flow phenomena related to three-dimensional flow separations and the unsteady nature caused by the interaction between primary and secondary air flows throughout the fan. In this paper, an aerodynamic study on a forward-curved centrifugal fan has been carried out Firstly we obtained the fan performance curves versus flow rates showing its unstable nature in the surging operation range. Secondly aerodynamic characterizations were carried out by investigating the velocity and pressure fields in the casing flow passage using a 5-hole pilot probe, at different operating conditions. Surface flow pattern near the cut-off area exhibits similar flow behavior above the best efficiency operating point, although the pressure level increases substantially with the Increase of flow rate. Vorticity in the casing passage flow occurs in all (low rates, downstream from the r-Z plane $\theta$=120 deg., where the position of its core changes with the circumferential location. Although complex, the general flow behavior were common, giving insight in its main aerodynamic features.

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지능형공간정보를 이용한 3차원 경관 영향 분석 (Analysis of Three Dimension Landscape Impact Using Intelligent Spatial Data)

  • 이현직;양승룡
    • 한국측량학회지
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    • 제27권4호
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    • pp.495-503
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    • 2009
  • 경관은 자연 인공요소 및 인간의 생활상 등으로 이루어진 일단의 지역환경적 특징을 나타내는 것으로 현재의 국토 개발과 보전에 있어서 매우 중요한 요소로 부각되고 있다. 그러나 과거 급속한 경제 성장과 개발 중심의 국토 사업으로 인하여 도심 및 산지에 대한 경관을 고려한 개발이 이루어지지 못하였다. 이에 본 연구에서는 지능형 공간정보를 이용하여 현재 개발 및 복구 계획이 이루어지고 있는 지역을 대상으로 개발 및 복구 전 후의 3차원 시뮬레이션을 통하여 현실적인 경관 영향 분석을 수행할 수 있었으며, 개발 및 복구에 따른 문제점을 쉽게 파악할 수 있었다.

Preliminary Results-Nature as Metaphor : Innovative Visualization of Accounting Information with Lotus Plants

  • Raungpaka, Voraphan;Savetpanuvong, Phannaphatr;Tanlamai, Uthai
    • Journal of Information Technology Applications and Management
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    • 제20권2호
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    • pp.1-14
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    • 2013
  • Learning accounting has always been a challenge for non-accounting students and managers. Understanding accounting information requires more than a numerical description of financial and income statements. Current accounting practice presents accounting reports in the form of tables with values or in two or three dimensional graphs generated by a spread sheet program. The present study proposes an alternative visualization with metaphor from nature as a learning device for novice users and managers. After surveying various kinds of plants, the lotus flower was chosen as an attractive analogy because every part of the plant from leaves to roots is usable and can have economic value. Moreover, lotus flowers, whether man-made or natural, can easily be part of a familiar, natural ecology representing both beauty and serenity. Results from online survey respondents (n = 220) showed that there was no significant difference on overall usability of the Lotus visualization between expert users and novice users. However, verbally-oriented users differed Significantly from visually-oriented users in their usability assessment, perceived usefulness, and intention to use the Lotus visualization.

Geostatistical algorithm for evaluation of primary and secondary roughness

  • Nasab, Hojat;Karimi-Nasab, Saeed;Jalalifar, Hossein
    • Geomechanics and Engineering
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    • 제24권4호
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    • pp.359-370
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    • 2021
  • Joint roughness is combination of primary and secondary roughness. Ordinarily primary roughness is a geostatistical part of a joint surface that has a periodic nature but secondary roughness or unevenness is a statistical part of that which have a random nature. Using roughness generating algorithms is a useful method for evaluation of joint roughness. In this paper after determining geostatistical parameters of the joint profile, were presented two roughness generating algorithms using Mount-Carlo method for evaluation of primary (GJRGAP) and secondary (GJRGAS) roughness. These based on geostatistical parameters (range and sill) and statistical parameters (standard deviation of asperities height, SDH, and standard deviation of asperities angle, SDA) for generation two-dimensional joint roughness profiles. In this study different geostatistical regions were defined depending on the range and SDH. As SDH increases, the height of the generated asperities increases and asperities become sharper and at a specific range (a specific curve) relation between SDH and SDA is linear. As the range in GJRGAP becomes larger (the base of the asperities) the shape of asperities becomes flatter. The results illustrate that joint profiles have larger SDA with increase of SDH and decrease of range. Consequencely increase of SDA leads to joint roughness parameters such Z2, Z3 and RP increases. The results showed that secondary roughness or unevenness has a great influence on roughness values. In general, it can be concluded that the shape and size of asperities are appropriate parameters to approach the field scale from the laboratory scale.

Effects of normal stress, shearing rate, PSD and sample size on behavior of ballast in direct shear tests using DEM simulation

  • Md Hussain;Syed Khaja Karimullah Hussaini
    • Geomechanics and Engineering
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    • 제35권5호
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    • pp.475-486
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    • 2023
  • Ballast particles have an irregular shape and are discrete in nature. Due to the discrete nature of ballast, it exhibits complex mechanical behaviour under loading conditions. The discrete element method (DEM) can model the behaviour of discrete particles under a multitude of loading conditions. DEM is used in this paper to simulate a series of three-dimensional direct shear tests in order to investigate the shear behaviour of railway ballast and its interaction at the microscopic level. Particle flow code in three dimension (PFC3D) models the irregular shape of ballast particles as clump particles. To investigate the influence of particle size distribution (PSD), real PSD of Indian railway ballast specification IRS:GE:1:2004, China high-speed rail (HSR) and French rail specifications are generated. PFC3D built-in linear contact model is used to simulate the interaction of ballast particles under various normal stresses, shearing rate and shear box sizes. The results indicate how shear resistance and volumetric changes in ballast assembly are affected by normal stress, shearing rate, PSD and shear box size. In addition to macroscopic behaviour, DEM represents the microscopic behaviour of ballast particles in the form of particle displacement at different stages of the shearing process.

Intellectual Property Disputes in the Era of the Metaverse: Complexities of Cross-Border Justice and Arbitration Consideration

  • Kye Hwan Ryu;Choong Mok Kwak
    • 한국중재학회지:중재연구
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    • 제33권3호
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    • pp.147-175
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    • 2023
  • The emergence of the metaverse, a complex three-dimensional virtual environment, has led to significant changes in the intellectual property (IP) landscape. This paper examines the challenges and legal intricacies of IP within the virtual realm, focusing on the unprecedented nature of these disputes and on the inadequacies of traditional jurisdiction methods. Drawing from international frameworks, including the International Law Association's Guidelines and WIPO's guides, the study critically explores arbitration as an alternate approach to metaverse IP disputes, analyzing its complexities and applicability. The paper further delves into challenges arising from diverse protection laws that pertain to the global nature of the metaverse, including the nuances of various digital assets like NFTs. By assessing jurisdictional difficulties, the paper addresses the adoption of decentralized justice platforms, and examines the role of Alternative Dispute Resolution (ADR) methods, this paper presents a comprehensive view of the evolving virtual legal field. It suggests that while innovative methods are emerging, traditional arbitration will likely remain the preferred choice for complex disputes, offering a balance of speed, cost-effectiveness, and legal robustness within the virtual world.

미니멀리즘이 현대패션에 미친 영향에 대한 연구 (A Study on the Influence that the Minimalism has on Modern Fashion)

  • 변지연;이순홍
    • 복식문화연구
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    • 제4권3호
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    • pp.427-445
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    • 1996
  • According as the fashion at the latter half part of the 20th century is diversified and made into high-class gradually, it is demanding the individuality of each one. Especially, since the beginning of 1980s, fashion came to represent the restoration mood in a modern style because of the popularization of post-modernism. And with this, it came to result in the reappearance of minimalism which was one of anti-culture in 1960s. In this study, this researcher grasped the appearance background, concept and structural concept of minimalism, and tried to study the influence that he minimalism had on fashion in the flow of fashion over the first half period of the 20th century. Minimalism is the fine art trend of American characteristic which quicked by the meeting of European culture and American culture, according as the new avant-grade art of Europe moved to America after World War II Minimalism which appeared, refusing the mechanisation, industrialization and mass production of America and the falsehood of consciousness and sensitivity under existing system remained obscure by the pop art which is the commercial fine art of same period, but it came to expand the domain of work possibility of modern fine art, and it became the basis of appearance of post-modernism. Minimalism has 4 kinds of structural features which are nonside nature, repetitiousness and environment nature with 3 dimensional feature which is issue nature. Minimalism is appearing in the exfcellent and future-oriented fashon of Andre Kureju t the time of 1960 well. Then science revolution and minimalism aroused the mini-revolution, and they made the compact radio in electric home appliances and the miniskirt in fashion appear. The features of minimal fashion as Retro '60' which appeared in the decedent mood with the 21st century just before on are as follows: First, the are the pursuit of concise plastic line. Second, it is the use of high tech material Third, the miniaturization in size amy be enumerated. Minimal fashion will appear s the positive confrontation from of mankind as the optimistic viewpoint about feature in the situation hat environment was destroyed and the resources were exhausted.

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진화론적 방법을 활용한 영성 개념분석 (Evolutionary Concept Analysis of Spirituality)

  • 고일선;최소영;김진숙
    • 대한간호학회지
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    • 제47권2호
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    • pp.242-256
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    • 2017
  • Purpose: This study was done to clarify attributes, antecedents, and consequences of spirituality. Methods: Rodgers's evolutionary concept analysis was used to analyze fifty seven studies from the literature related to spirituality as it appears in systematic literature reviews of theology, medicine, counseling & psychology, social welfare, and nursing. Results: Spirituality was found to consist of two dimensions and eight attributes: 1) vertical dimension: 'intimacy and connectedness with God' and 'holy life and belief', 2) horizontal dimension: 'self-transcendence', 'meaning and purpose in life', 'self-integration', and 'self-creativity' in relationship with self, 'connectedness' and 'trust' in relationship with others neighbors nature. Antecedents of spirituality were socio-demographic, religious, psychological, and health related characteristics. Consequences of spirituality were positive and negative. Being positive included 'life centered on God' in vertical dimension, and among horizontal dimension 'joy', 'hope', 'wellness', 'inner peace', and 'self-actualization' in relationship with self, 'doing in love' and 'extended life toward neighbors and the world' in relationship with others neighbors nature. Being negative was defined as having 'guilt', 'inner conflict', 'loneliness', and 'spiritual distress'. Facilitators of spirituality were stressful life events and experiences. Conclusion: Spirituality is a multidimensional concept. Unchangeable attributes of spirituality are 'connectedness with God', 'self-transcendence', 'meaning of life' and 'connectedness with others nature'. Unchangeable consequences of spirituality are 'joy' and 'hope'. The findings suggest that the dimensional framework of spirituality can be used to assess the current spiritual state of patients. Based on these results, the development of a Korean version of the scale measuring spirituality is recommended.

포스트모던시대 조형예술의 장소성과 환경 (Site-Specificity and Environment of Visual Art in the Postmodern Era)

  • 이봉순
    • 조형예술학연구
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    • 제13권1호
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    • pp.39-60
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    • 2008
  • Nature/Landscape is surrounding space in which we make living. It is considerably comprehensive tenn. but on the other hand, the site can be existence, experience, and certain circumstance with boundaries. Based on these places, through contemporary art criticism, this study is to contemplate how art since 1960s, especially, site-specific art in three-dimensional space intervene in the environment. Artists of today put more value on the process and act of art making founded on the external, and they tend to create the characteristic of site or to indicate linguistic documentation. Moreover, a large-scale tendency of contemporary sculpture and 'occupation of specific site' seems to accede spatial conception from architecture. The core that recognizes these artworks is with body, that is to say, the space in which Self becomes the subject by changing the structure of the work while moving around it. In particular, 'Site-specific Art (in situ)' sometimes determines the form inward or outward It also relates directly on viewer's five senses by looking, hearing, and feeling, touching, and interacting. For example, in Richard Serra's , the viewer who moves around the work has the role to manipulate the movement of the work by perception. Works of In situ and works that planned for specific site suggest 'occupation of site' as of the function of the work These sites are ideal and special as well as being independent. Ultimately, it seems that the creative process of contemporary artists is to carry those intended form on the structure of perception. Furthermore, law of nature such as entropy, and acceptance of contingency helped organic structure of artwork become more abundant. For Robert Smithson, entropy suggests of reaching to a state of equilibriumin which everything is the same. This means that any core is justifiable and any rank is possible. Because the world without a core is a labyrinth of boundless exploration.

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헬름홀츠 공명기들로 구성된 음향 메타물질의 파동전파 특성 (Wave Propagation Characteristics of Acoustic Metamaterials with Helmholtz Resonators)

  • 권병진;조충희;박광춘;오일권
    • 한국소음진동공학회논문집
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    • 제23권2호
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    • pp.167-175
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    • 2013
  • The wave propagation characteristics of an acoustic metamaterial composed of periodically repeated one-dimensional Helmholtz resonator array was investigated considering the effects of dimensional changes of the resonator geometry on the transmission coefficient and band gap. The effective impedance and transmission coefficient of the acoustic metamaterials are obtained based on the acoustic transmission line method. The designed acoustic metamaterials exhibit band gaps and negative bulk modulus that are non-existent properties in the nature. The band gap of the acoustic metamaterial is strongly dependent on the geometry parameters of Helmholtz resonators and lattice spacing. Also, a new type of metamaterial that is periodically constructed with two different resonators was designed to open the local resonance band gap without change of Bragg scattering.