• 한국연소학회:학술대회논문집
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• 한국연소학회 1997년도 제15회 KOSCO SYMPOSIUM 논문집
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• pp.1-11
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• 1997

The soot and OH radical distributions have been experimentally studied in ethylene and propane laminar diffusion flames. The integrated soot volume fraction was measured along the centerline of a flame using a laser light extinction method. Planar laser light scattering and PLIF techniques are employed for the soot and OH radical distribution measurements utilizing Nd:YAG laser and OPO, FDO system. The concentration of OH radical is rapidly decreased at the edge of sooting region, which implies the importance of OH radical species on the soot oxidation process. For ethylene flames, the addition of air in fuel moves the OH radical distribution towards the center line of a flame at the soot oxidation region, while the concentration of OH radical remains relatively high at the soot formation region. The interaction between soot particles and OH radicals becomes more active with fuel-air at the soot oxidation region. For propane flames, however, any indication of the increased interaction between soot particles and OH radicals with fuel-air was not noticed.

• International Journal of Fluid Machinery and Systems
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• 제9권2호
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• pp.143-149
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• 2016

In this study, a method for the multi-objective optimization of an impeller for a centrifugal compressor using fluid-structure interaction (FSI) and response surface method (RSM) was proposed. Numerical simulation was conducted using ANSYS CFX and Mechanical with various configurations of impeller geometry. Each design parameter was divided into 3 levels. A total of 15 design points were planned using Box-Behnken design, which is one of the design of experiment (DOE) techniques. Response surfaces based on the results of the DOE were used to find the optimal shape of the impeller. Two objective functions, isentropic efficiency and equivalent stress were selected. Each objective function is an important factor of aerodynamic performance and structural safety. The entire process of optimization was conducted using the ANSYS Design Xplorer (DX). The trade-off between the two objectives was analyzed in the light of Pareto-optimal solutions. Through the optimization, the structural safety and aerodynamic performance of the centrifugal compressor were increased.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2007년도 춘계학술대회A
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• pp.780-785
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• 2007

Accurate and fast haptic simulations of deformable objects are desired in many applications such as medical virtual reality. In haptic interactions with a coarse model, the number of nodes near the haptic interaction region is too few to generate detailed deformation. Thus, local refinement techniques need to be developed. Many approaches have employed purely geometric subdivision schemes, but they are not proper in describing the deformation behavior of deformable objects. This paper presents a continuum mechanics-based finite element adaptive method to perform haptic interaction with a deformable object. This method superimposes a local fine mesh upon a global coarse model, which consists of the entire deformable object. The local mesh and the global mesh are coupled by the s-version finite element method (s-FEM), which is generally used to enhance accurate solutions near the target points even more. The s-FEM can demonstrate a reliable deformation to users in real-time.

• Steel and Composite Structures
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• 제5권4호
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• pp.259-269
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• 2005

Many slab-on-girder bridges around the world are being assessed because they are approaching the end of their anticipated design lives or codes are permitting higher allowable loads. Current analytical techniques assume that the concrete and steel components act independently, typically requiring full-scale load testing to more accurately predict the remaining strength or endurance of the structure. However, many of the load tests carried out on these types of bridges would be unnecessary if the degree of interaction resulting from friction at the steel-concrete interface could be adequately modeled. Experimental testing confirmed that interface friction has a negligible effect on the flexural capacity of a slab-on-girder beam however, it also showed that interface friction is significant under serviceability loading. This has led to the development of an improved analytical technique which is presented in this paper and referred to as the slab-on-girder mixed analysis service load assessment approach.

• 제어로봇시스템학회논문지
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• 제10권9호
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• pp.771-778
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• 2004

Recently, various applications of robot system become more popular in accordance with rapid development of computer hardware/software, artificial intelligence, and automatic control technology. Formerly robots mainly have been used in industrial field, however, nowadays it is said that the robot will do an important role in the home service application. To make the robot more useful, we require further researches on implementation of natural communication method between the human and the robot system, and autonomous behavior generation. The gesture recognition technique is one of the most convenient methods for natural human-robot interaction, so it is to be solved for implementation of intelligent robot system. In this paper, we describe the state-of-the-art of advanced gesture recognition technologies for intelligent robots according to three methods; sensor based method, feature based method, appearance based method, and 3D model based method. And we also discuss some problems and real applications in the research field.

• 아동학회지
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• 제31권1호
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• pp.219-234
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• 2010

This study examined the influence of mothers' reading and scaffolding behaviors on children's emotional experiences and memory recall during picture book reading. Sixty children, aged 6 and their mothers participated in this study. Each child-mother dyad was observed in a lab setting which was designed to evaluate child-mother interactions during a picture book reading. The data were analyzed using correlation and multiple regression techniques. Our results indicated that mothers' task-oriented reading behavior affected the children's lack of positive emotions, whereas mothers' fun-oriented reading behavior was associated with the children's positive emotions. The task-oriented reading behavior also accounted for children's poor memory performance in relation to the book. These results were discussed in terms of the relationship between emotion and cognition through book reading experiences.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2004년도 추계학술대회 논문집 Vol.17
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• pp.711-714
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• 2004

Chemical mechanical polishing (CMP) has been widely accepted for the global planarization of multi-layer structures in semiconductor manufacturing. However, it still has various problems to the CMP equipment, in particular, among the CMP components, process variables are very important parameters in determining the removal rate and non-uniformity. Using a design of experiment (DOE) approach, this study was performed investigating the interaction between the various parameters such as turntable and head speed, down force and back pressure during CMP. Using statistical analysis techniques, a better understanding of the interaction behavior between the various parameters and the effect on removal rate, no-uniformity and ETC (edge to center) is achieved.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2001년도 춘계학술대회논문집
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• pp.85-89
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• 2001

The problem of the transient interaction of a plane acoustic shock wave which has an infinitely steep wave front with a cylindrical or spherical elastic shell has been studied analytically from early fifties based on the integral transform and series solution techniques. Huang adopted an inverse Laplace transform, and used a finite number of terms of the infinite series expansion of the equations for the shells. In the 1990s, the results have been used by many authors for validation of computer codes. The object of this paper is to discuss the interaction between a moving source and submerged spherical shells. Since the center of source is moving the first contact location between the waves and shell changes depending on the source velocity and distance. These are considered in the analysis. Furthermore, constant source strength and decreasing strength are considered in the analysis. Radial velocities at several locations on the structure are obtained and the results are discussed.

• 대한화학회지
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• 제34권4호
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• pp.325-330
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• 1990

여러 온도와 압력에서 초임계 암모니아내의 카페인의 용해도를 측정함으로써 용해도와 암모니아의 밀도 사이의 관계를 간단한 식으로 나타낼 수 있었다. 이 식을 이용하여 암모니아와 카페인 사이의 상호작용 비리알 계수를 결정한 다음 이로부터 Lennard-Jones 퍼텐셜함수의 파라미터를 결정하였다. 그리고 이미 보고된 초임계 암모니아내의 나프탈렌의 용해도와 초임계 이산화탄소내의 카페인 및 나프탈렌의 용해도 자료로부터 같은 방법으로 결정된 상호작용 비리알 계수와 Lennard-Jones 퍼텐셜함수를 각각 비교 검토하였다.

• 한국인터넷방송통신학회논문지
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• 제14권3호
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• pp.105-110
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• 2014

휘처 지향 소프트웨어 프로덕트 라인 공학 방법은 휘처 단위로 프로덕트 라인의 핵심 자산을 개발하고, 이를 조합하여 쉽게 다양한 제품을 개발한다. 하지만 휘처를 조합하여 제품을 개발하는 동안 휘처상호작용문제를 효과적으로 대응하지 못하면, 개발된 제품이 원하는 대로 동작하지 않을 수 있다. 본 논문에서 휘처 간에 발생될 수 있는 원하지 않는 상호작용을 검출하는 기법과 이를 효과적으로 모듈화하는 방법을 제안한다. 제안된 방법의 적용가능성을 평가하기 위해서 공학용 계산기 프로덕트 라인에 적용하였다.