• Title/Summary/Keyword: Multi-dimensional development

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Eulerian Particle Flamelet Modeling for Combustion Processes of Bluff-Body Stabilized Methanol-Air Turbulent Nonpremixed Flames

  • Kim, Seong-Ku;Kang, Sung-Mo;Kim, Yong-Mo
    • Journal of Mechanical Science and Technology
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    • v.20 no.9
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    • pp.1459-1474
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    • 2006
  • The present study is focused on the development of the RIF (Representative Interactive Flamelet) model which can overcome the shortcomings of conventional approach based on the steady flamelet library. Due to the ability for interactively describing the transient behaviors of local flame structures with CFD solver, the RIF model can effectively account for the detailed mechanisms of $NO_x$ formation including thermal NO path, prompt and nitrous $NO_x$ formation, and reburning process by hydrocarbon radical without any ad-hoc procedure. The flamelet time of RIFs within a stationary turbulent flame may be thought to be Lagrangian flight time. In context with the RIF approach, this study adopts the Eulerian Particle Flamelet Model (EPFM) with mutiple flamelets which can realistically account for the spatial inhomogeneity of scalar dissipation rate. In order to systematically evaluate the capability of Eulerian particle flamelet model to predict the precise flame structure and NO formation in the multi-dimensional elliptic flames, two methanol bluffbody flames with two different injection velocities are chosen as the validation cases. Numerical results suggest that the present EPFM model has the predicative capability to realistically capture the essential features of flame structure and $NO_x$ formation in the bluff-body stabilized flames.

Development of New Methods for Position Estimation of Underground Acoustic Source Using a Passive SONAR System

  • Jarng, Soon-Suck;Lee, Je-Hyeong;Ahn, Heung-Gu
    • Transactions on Control, Automation and Systems Engineering
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    • v.2 no.1
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    • pp.69-75
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    • 2000
  • The aim of the work described in this paper is to develop a complex underground acoustic system which detects and localizes the origin of an underground hammering sound using an array of hydrophones located about 100m underground. Three different methods for the sound localization will be presented, a time-delay method, a power-attenuation method and a hybrid method. In the time-delay method, the cross correlation of the signals received from the array of sensors is used to calculate the time delays between those signals. In the power-attenuation method, the powers of the received signals provide a measure of the distances of the source from the sensors. In the hybrid method, both informations of time-delays and power-ratios are coupled together to produce better performance of position estimation. A new acoustic imaging technique has been developed for improving the hybrid method. This new acoustic imaging method shows the multi-dimensional distribution of the normalized cost function, so as to indicate the trend of the minimizing direction toward the source location. For each method the sound localization is carried out in three dimensions underground. The distance between the true and estimated origins of the source is 28m for a search area of radius 250m.

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Stereo Calibration Using Support Vector Machine

  • Kim, Se-Hoon;Kim, Sung-Jin;Won, Sang-Chul
    • 제어로봇시스템학회:학술대회논문집
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    • 2003.10a
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    • pp.250-255
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    • 2003
  • The position of a 3-dimensional(3D) point can be measured by using calibrated stereo camera. To obtain more accurate measurement ,more accurate camera calibration is required. There are many existing methods to calibrate camera. The simple linear methods are usually not accurate due to nonlinear lens distortion. The nonlinear methods are accurate more than linear method, but it increase computational cost and good initial guess is needed. The multi step methods need to know some camera parameters of used camera. Recent years, these explicit model based camera calibration work with the development of more precise camera models involving correction of lens distortion. But these explicit model based camera calibration have disadvantages. So implicit camera calibration methods have been derived. One of the popular implicit camera calibration method is to use neural network. In this paper, we propose implicit stereo camera calibration method for 3D reconstruction using support vector machine. SVM can learn the relationship between 3D coordinate and image coordinate, and it shows the robust property with the presence of noise and lens distortion, results of simulation are shown in section 4.

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A Study on Structural Model of Work-Values, Job Satisfaction and Task Performance of Generation Y Staff in the Hotel Industry

  • Choi, Hyunjung
    • Culinary science and hospitality research
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    • v.23 no.6
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    • pp.78-88
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    • 2017
  • The main goal of this study was to demonstrate the causal relationships between multi-dimensional work-values, job satisfaction and task performance of Y generational employee in the Korean hotel industry. In order to achieve the purpose, the data were collected from Y generational employees working in the major cities in Korea. To analyze the data, frequency, exploratory factor analysis, reliability analysis, PROCESS Macro analysis and simple regression analysis were undertaken by using SPSS 18.0. The results were as follows; 1. Work-values were found out as five factors; Prestige workvalues, Personal development work-values, Work condition work-values, Personal welfare work-values, Social/ Altruistic work-values. 2. All five factors were found to be significant in enhancing job satisfaction. 3. Two factors which were prestige work-values and personal welfare work-values were found to be significant in facilitating task performance. 4. Job satisfaction was revealed as a mediator between all work-value factors and task performance. This study provided practical information about work-values of Y generational hoteliers to positively affect their job satisfaction and task performance. This study also confirmed that it is important to enhance job satisfaction in order to make employees perform their service duties better.

A Study on Design and Color Preference Investigation using WWW (WWW을 활용한 디자인과 색채 기호 조사에 관한 연구)

  • Kim, Hyung-Min;Kwon, Eun-Sook
    • Journal of the Korea Computer Graphics Society
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    • v.2 no.1
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    • pp.39-47
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    • 1996
  • Consumer's needs, pursuing diverse lifestyles, can be identified systematically by the development of design research method with computer technologies. Color, which is the most important factor in industrial design, has been regarded as possessing difficulties in collecting and analyzing reliable data, because it has multi-dimensional features. The purpose of this paper is to develop a new research method for design and color preference investigation, and to provide the possibilities of applying this method into the traditional color research which has many limitations in time, space, and money. This paper emphasizes that the new method using visual and concrete 3D modeling of a product can enhance the reliability of collecting and analyzing data comparing with traditional linguistic and abstract one.

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Development of Integrated Planning Simulation Model for Supporting Rural Village Planning (농촌마을계획 지원을 위한 통합계획모의모형의 개발)

  • Kim, Dae-Sik;Chung, Ha-Woo
    • Journal of Korean Society of Rural Planning
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    • v.9 no.4 s.21
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    • pp.43-51
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    • 2003
  • This study aims to integrate the simulation models for rural settlement planning (SimRusep) in the district level (Myon) area of rural counties. The SimRusep, which has two modules of key villages selection and spatial planning for the selected villages, consists of four sub-models such as the spatial location-allocation model of center villages (SLAMCV), the potential centrality evaluation model (PCEM), the land use planning model (LUPM), and the 3-dimensional spatial planning modeller (3DSPLAM). Basically, map data of the integrated system which can be operated on the UNIX environment is inputted and treated using GIS (ARC/INFO) and then its village planning results is graphically presented on the AutoCAD. In order to verify the practical applicabilities of the SimRusep, an administrative area, Ucheon-myun, HoengSung-gun, KangWon-do, was selected as a case study area. It was well operated in the strategic application trials considering application of each sub-model in the study area. The operation results of the SimRusep showed the possibilities of realtime simulation from the selection of key village to its final stereoscopic presentation of planned results. Alternative village plan proposals can be swiftly drafted, which means very practical support for decision making process and public participation.

Understanding Medicine as a Multi-dimensional Concept in the Legal Context (의료 개념의 다층적 이해와 법)

  • Kim, Na-Kyoung
    • The Korean Society of Law and Medicine
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    • v.11 no.2
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    • pp.75-112
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    • 2010
  • This article analyses the concept of medicine in the legal context. It is not easy to define the concept of medicine because medical practice has various dimensions and the situation in which the practice is performed has a broad variety. The duty of medical law is to build the boundary of protection in that the nature of medicine would not be distorted by the factors of social systems like industry or governmental authorities. Without understanding the various dimensions - especially the dimension of Humanities and Sociology - of the medicine it is not possible to draw the limit on the performance of medicine appropriately. Concerning the medical practice (especially in the context of the regulation of medical licence), the enacted law (Medical Act) defines the concept just for form's sake and it finally depends on the interpretation of the legal enforcement authorities. Moreover, between the judgments of the courts there exists no coherent principles for the regulation and the interpretation of the Medical Act depends often on the riskiness, the abstract concept, which finally leads the interpretation to depend on the subject of the practice. On the contrary, the development and scientific movement of the technology tends to tighten the range of the medical professionals of medical practice and the perspectives of the medicine. Medical act is actually oriented at the patient's understanding of him- or herself. The above-mentioned tendency of the interpretation and the legal policy could lead the medicine away from its nature.

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The Extract of 3D Road Centerline Using Video Camera (비디오 카메라를 이용한 3차원 도로중심선 추출)

  • Seo Dong-Ju;Lee Jong-Chool
    • International Journal of Highway Engineering
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    • v.8 no.1 s.27
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    • pp.65-75
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    • 2006
  • According to development of computer technology, the utilization of the fourth generation of digital photogrammetry progresses favorable. Especially the method of using digital video camera is very practicable and has an advantage such as a profitability for the amateur. In road field which if centrical facilities of national industry, this method was utilized to acquire road information for the safety diagnosis or maintenance. In this study, 3-dimensional position information of road centerline was extracted using digital video camera which has practicality and economical efficiency. This data could be a basic source in road information project.

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A Study on the Spatial Planning of Community in Urban Underground Space for Sustainable Urban Regeneration (지속가능한 도시재생을 위한 도심 지하공간의 커뮤니티 공간 계획에 관한 연구)

  • Ha, Mi-Kyoung;Kim, A-Hyun;Lee, Hyo-Chang
    • Korean Institute of Interior Design Journal
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    • v.22 no.3
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    • pp.205-216
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    • 2013
  • Korean cities need sustainable urban regeneration based on the effective application of space and resource. Especially a sustainable urban regeneration needs the activation of community in the urban underground space as urban development center. The purpose of this study is to propose elements and factors of spatial planning of community in urban underground space for sustainable urban regeneration and to propose the characteristics of spatial planning of community in urban underground space according to strategies of sustainable urban regeneration. The research methods of this study used to conduct research include precedent study reviews and survey. The conclusions of this study are as following; The application of various factors related to spatial planning aspect of communication, supportive cultural facilities, accessibility and nature is needed for creating a sustainable urban regeneration. Especially, in urban underground space, the application of spatial planning for community activation considered strategies of sustainable urban regeneration should be necessary. And introduction of cultural facilities, multi-dimensional pedestrian network for accessibility and natural elements for activating community in urban underground space are needed for making sustainable urban regeneration.

An Overview of The Commercialisation of The Spray Forming Process

  • Leatham, Alan
    • Journal of Powder Materials
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    • v.3 no.4
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    • pp.227-232
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    • 1996
  • (i) The development of a metallurgical bond during the spray forming of clad products has offered the possibility of manufacturing large rolls, including those used in hot and cold strip mills. Small rolls are already being produced in Japan. (ii) Technical developments, including the use-of-multi-atomizers have resulted in the elimination of porosity from the internal bore of a sprayed tube. Bimetallic tubing can also be manufactured and the installation of a 4.5 ton tube plant in the USA should provide low operation costs. (iii) Spray forming offers a potentially low cost manufacturing route for superalloy ring/casing components in high strength superalloys. (iv) A large pilot plant has been built for the spray forming of ultra-clean superalloys for turbine disc applications. (v) Using twin-atomizing technology, special steel billets have been spray formed up to 400mm diameter with deposition yields in excess of 90%. (vi) Al/Si alloy extrusion billets with excellent dimensional tolerances are being manufactured for large scale automotive applications. Several new aluminum alloys have also been developed, including high strength, low density and low cocfficient of expansion materials. (vii) New copper alloys have been developed and pilot plants are in operation to produce these alloys once markets have become established.

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