• Tribology and Lubricants
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• 제39권3호
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• pp.102-110
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• 2023

This study aims to quantify the variation in the performance of a tilting pad journal bearing (TPJB) owing to the elastic deformation of its pad. To this end, we first defined a parameter, "elastic preload", and predicted the changes in the performance of the TPJB, as a function of the preload amount. We used the iso-viscosity Reynolds equation, which ignores the temperature rise due to viscous shear in thin films, and the resultant thermal deformation of the bearing structure. We employed a three-dimensional finite element model to predict the elastic deformation of the bearing pad, and a transient analysis, to converge to a static equilibrium condition of the flexible pads and journal. Conducting a modal coordinate transformation helped us avoid heavy computational issues arising from a mesh refinement in the three-dimensional finite element pad model. Moreover, we adopted the Hertzian contact model to predict the elastic deformation at the pivot location. With the aforementioned overall strategy, we predicted the performance changes owing to the elastic deformation of the pad under varying load conditions. From the results, we observed an increase in the preload due to the pad elastic deformation.

• 한국멀티미디어학회논문지
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• 제15권10호
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• pp.1257-1263
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• 2012

본 연구는 3D레이저 스캔 방식으로 계측된 인체 데이터를 대상으로 하여 인체의 여러 동작들에 대한 애니메이션 모듈 구현을 목표로 하였다. 이를 위하여 애니메이션 회전을 위한 기준점인 인체의 골격 기준점을 추출하고 추출된 기준점을 이용하여 골격을 잡고 각 골격에 따른 계층트리를 구성하였다. 구성된 계층트리의 골격에 해당되는 오브젝트 정점들을 골격과 연결하고 주어진 애니메이션 3차원 정점들에 행동 패턴을 적용하여 스캔데이터에 애니메이션을 구현하였다.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2000년도 춘계학술대회논문집A
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• pp.879-883
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• 2000

A system for measuring and adjusting the oscillating frequency of a balance wheel whick determins the accuracy of mechanical timers. The balance wheel oscillates rotatively suspended by a hair spring which is welded at the other end to the pivot tube. The natural oscillatory frequency of the balance wheel is determined by the length of hairspring from the balance wheel to the point if other parameters the length in the torsional oscillation model are not changed, so the frequency of the balance wheel can be adjusted to meet a requirement by the adjustment of the hairspring length using ultrasonic welding. And the movement of wheel teeth is measured in realtime by a high speed photo fiber sensor and Auto Correlation is used to find a more accurate oscillation period from the measured signal with some variations.

• 한국유체기계학회 논문집
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• 제8권6호
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• pp.47-54
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• 2005

An oscillating foil can produce a driving force through the generation of a reversed $K\'{a}rm\'{a}n$ vortex street, and it can be expected to be a new highly effective propulsion system. A simple pitching foil model was made and it was operated within a water channel. The wake formation behind a pitching foil was visualized and unsteady fluid forces were measured using a 6-axis force sensor based on force and moment detectors. We have been examined various conditions such as reduced frequency, amplitude and pivot point in NACA 0010. The results showed that thrust coefficients increased with a reduced frequency. We also presented the experimental results on the characteristics of a pitching foil at various parameters.

• 한국디지털건축인테리어학회논문집
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• 제7권1호
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• pp.35-42
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• 2007

Common residential environment is synthetic forms promote with organic organization of varied cultures and images. Users perceive and classify about these environments of feeling and atmosphere of each elements through their experiences and memories, not fixed point of view. In Korea, park designing of common residential room is in operation monotonously attach importance to economical efficiency without aesthetic structures, varied tries of materials, multiplicity, congruity of surrounding, and user-oriented plan. Recently, in policy of park designing has elements that obstruct to characteristic of environment because of applied to wrong guidelines which are end in investigation to model of an advanced countries'. In conclusion, this investigation shows improve on quality of park planning with the pivot of the matter is for users of common residential room. and park planning needs to multidimensional achieve.

• 산업공학
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• 제10권3호
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• pp.55-62
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• 1997

Among the driving methods of CALS, Electronic Data Interchange (EDI), the pivot of procurement and logistics, is becoming the standard of data interchange. In this article, we examine the standard, growth, and status of EDI, and present a scheme to make it available via Internet that grow to be a standardized network, in comparison with a method to use a Value Added Network(VAN). So we studied an implementation of EDI system to exchange and process the business intra-works in order to integrate it into Intranet environment. As well, we present a client/server model running under Intranet environment, and a system with a format server to share the load of server and client. To do this, we list the functions and requirements of EDI system, connect a database to the Intranet, and develop applications using $Java^{TM}$.

• 한국정보처리학회논문지
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• 제1권3호
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• pp.290-298
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• 1994

본 논문은 p(p= $n^{1-x}$, 0〈x〈1)개 프로세서가 존재하는 EREW-PRAM 모델 병 렬 컴퓨터에서 시간 복잡도가 0( $n^{x}$ log n)이며 비용 (최악의 실행시간*프로세서 수)은 0(nlogn)이고, 자료 이동도가 0( $n^{1-}$x＋ $n^{x}$ )인 병렬 정렬 알고리즘을 제안한다. 병렬 정렬 알고리즘은 리스트를 p개 특정키를 중심으로 분리한 다음 블럭 의 크기를 거의 일정하게 할 수 있는 엔코딩 기법을 사용했다.다.

• Current Optics and Photonics
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• 제8권3호
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• pp.300-306
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• 2024

To solve the nozzle swing angle non-contact measurement problem, we present a nozzle pose estimation algorithm involving weighted measurement uncertainty based on rotation parameters. Firstly, the instantaneous axis of the rocket nozzle is constructed and used to model the pivot point and the nozzle coordinate system. Then, the rotation matrix and translation vector are parameterized by Cayley-Gibbs-Rodriguez parameters, and the novel object space collinearity error equation involving weighted measurement uncertainty of feature points is constructed. The nozzle pose is obtained at this step by the Gröbner basis method. Finally, the swing angle is calculated based on the conversion relationship between the nozzle static coordinate system and the nozzle dynamic coordinate system. Experimental results prove the high accuracy and robustness of the proposed method. In the space of 1.5 m × 1.5 m × 1.5 m, the maximum angle error of nozzle swing is 0.103°.

• 한국콘텐츠학회논문지
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• 제15권10호
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• pp.561-569
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• 2015

소규모 창업기업은 사업을 진행하면서 자신의 비즈니스모델을 자체 검증하는데 어려움을 겪고 있다. 경영학적 배경지식이 부족한 상태에서는 더더욱 어려움이 많다. 이러한 이유로 소규모 창업기업은 자신들이 현재 진행하고 있는 비즈니스모델을 스스로 분석하여 경영진단을 할 수 있는 쉬운 방법을 원하고 있다. 본 연구에서는 비즈니스모델 개발에 활용되고 있는 비즈니스모델 캔버스(Business Model Canvas)를 통해 그 가능성을 살펴보았다. 비즈니스모델캔버스는 기업이 어떻게 수익을 창출하는지 그 원리를 9개의 블록으로 간단하게 도식화한 것이다. 이 모델은 비즈니스모델을 분석하는 도구로 활용할 수 있으며, 사업하는 과정에서의 문제점을 확인하여 개선안을 도출하기가 쉽다는 장점이 있다. 따라서 본 연구에서는 비즈니스모델캔버스를 이용하여 건강기능식품 창업기업의 비즈니스모델을 분석하고 사업화 과정에서 드러나는 문제점을 파악하여 전략적 제언을 제시하였다. 이러한 결과는 창업교육을 위한 창업사례연구 자료로 활용할 수 있다.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2001년도 춘계학술대회논문집
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• pp.1111-1116
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• 2001

A transient T-F(time-frequency) signal processing technique is applied to a tilt drop and a linear shock test rigs for identification of shock characteristics of hard disk drive (HDD). The T-F technique essentially tracks the shock characteristics of pivot point response as well as head slap and lift-off phenomena. From the T-F analysis result, the shock characteristic in HDD is modeled by the two degree of freedom coupled-dynamic system, which consists of actuator arm and suspension. As shock designing tool, the maximax shock response spectrum is employed for prediction of shock performance. Finally, the shock control technique is tested with newly designed actuator arm and suspension. Experimental head slap test result shows that the shock performance is much higher with the new shockproof designed model than the current model