• Communications for Statistical Applications and Methods
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• 제23권2호
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• pp.93-103
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• 2016

In the paper, we discuss dimension reduction of predictors ${\mathbf{X}}{\in}{{\mathbb{R}}^p}$ in a regression of $Y{\mid}{\mathbf{X}}$ with a notion of sufficiency that is called sufficient dimension reduction. In sufficient dimension reduction, the original predictors ${\mathbf{X}}$ are replaced by its lower-dimensional linear projection without loss of information on selected aspects of the conditional distribution. Depending on the aspects, the central subspace, the central mean subspace and the central $k^{th}$-moment subspace are defined and investigated as primary interests. Then the relationships among the three subspaces and the changes in the three subspaces for non-singular transformation of ${\mathbf{X}}$ are studied. We discuss the two conditions to guarantee the existence of the three subspaces that constrain the marginal distribution of ${\mathbf{X}}$ and the conditional distribution of $Y{\mid}{\mathbf{X}}$. A general approach to estimate them is also introduced along with an explanation for conditions commonly assumed in most sufficient dimension reduction methodologies.

• 한국지능시스템학회논문지
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• 제20권4호
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• pp.489-496
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• 2010

본 논문은 3D 환경에서의 스웜시스템을 위한 자기조직화 방법을 제시한다. 스웜 시스템의 자기조직화를 위하여 인력과 척력을 이용하는 인공 포텐셜 함수(Artificial Potential Function, 이하 APF)를 사용하였다. 제안된 연구에서는 2D 환경에서 자기조직화를 위해 사용되어왔던 다양한 포텐셜들을 3D 환경에 맞게 확장 설계한다. 지면이나 수면 등의 경계면을 가지는 3D 환경의 특성을 고려하여 지면 포텐셜(Ground Potential)을 제안한다. 지면 포텐셜을 고려하지 않았을 때와 고려할 때의 비교 결과를 통해 지면 포텐셜의 필요성과 효과를 보여준다. 마지막으로, 다양한 시뮬레이션 결과를 통해 3D 환경에서 확장된 인공포텐셜과 그 성질의 효율성을 보여준다.

• 한국공작기계학회:학술대회논문집
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• 한국공작기계학회 2003년도 춘계학술대회 논문집
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• pp.255-259
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• 2003

Moire topography method isa well-known non-contacting 3-D measurement method as afast non-contact test for three-dimension shape measuring method. Recently, it's important to study the automatic three-dimension measurement by moire topography because it is frequently applied to the reverse engineering , the medical , the entertainment fields. Three-dimension measurement using projection of moire topography is very attractive because of its high measuring speed and high sensitivity. In this paper, the classical moire method is computerized-so called digital moire when a virtual grating pattern is projected on a surface, the captured image by the CCD camera has three-dimension information of the objects. The moire image can be obtained through a simple image processing and a reference grating pattern. and it provides similar results without physical grating pattern. digital projection moire topography turn out to be very effective for the three-dimension measurement of objects. Using different N-bucket algorithm method of digital projection moire topography is tested to measuring object with the 2-ambiguity problem. Experimental results prove that the proposed scheme is capable of finding measurement errors that decreased more by using the four-three step algorithm method instead of the same step in the phase shifting of different pitch.

• 한국조경학회지
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• 제25권3호
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• pp.47-55
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• 1997

A vacation destination was conceptualized to be chosen through a three-stage process consisting of an early consideration set formation, a late consideration set formation, and a final selection stage. Choice criteria were defined as an individual's belief toward the relationships between perceived attributes, expected outcomes, and the destination. And these criteria were assumed to be divided into benefit-related dimension and perceived risk-related dimension. Through two pilot surveys, 13 items which have 4 factors were identified. used on 4 factor structures, the benefit-related dimension was identified to be consisted of three sub-dimensions, "historic/cultural", "escaped" and "naturalness". A longitudinal panel survey was used to test the differences of the importance of choice dimensions through the choice process. The importance of benefit-related dimension was decreased through the choice process as hypothesized except "naturalness" factor. And as hypothesized, the importance of perceived risk-related dimension was increased.

• 한국어류학회지
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• 제18권3호
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• pp.209-215
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• 2006

한국의 퉁가리과 어류 3종의 형태학적 특성을 classical dimension과 truss dimension을 사용하여 파악하였다. Arc sin square root 전환 후, 18가지의 계측형질을 체장에 대한 비율로, 그리고 3가지의 계측형질은 두장에 대한 비율로 각각 분석하였다. 퉁사리, Liobagrus obesus는 classical dimension과 truss dimension의 4가지 계측 형질이 퉁가리, L. andersoni와 자가사리, L. mediadiposalisa에 비하여 컸다 (P<0.05). 퉁사리와 퉁가리는 truss dimension의 3가지 계측형질이 자가사리보다 컸다 (P<0.05). 조사된 퉁가리과 어류의 6가지 계측형질에서는 유의적인 차이가 없었다. 본 연구에 사용된 dimension들은 한국산 퉁가리과 어류들을 구별할 수 있는 적절한 분류학적 지표로 사용될 수 있으리라 사료된다.

• 복식문화연구
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• 제11권2호
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• pp.219-230
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• 2003

The purpose of this study was to analyze the structure of consumption emotions that consumers experienced in the process of consuming apparel products. Data was collected from 144 female college students living in Busan, and analyzed by salience, diversity, H-index, Clamor's V, and multi-dimensional scaling. The results showed as following; 1. The consumption emotions related to apparel products appeared three dimensions; ‘Relaxed-tense’ dimension, ‘Pleasant-unpleasant’ dimension, and ‘Outward-inward’ dimension. Considering elements of consumption system, the dimensions of consumption emotions in relation to apparel performances were 'Pleasant-unpleasant' and ‘Outward-inward’. The dimensions of consumption emotions experienced in usage situations were ‘Relaxed-tense’ and ‘pleasant-unpleasant’. The consumption emotions related to specific products were composed of ‘Pleasant-unpleasant’ dimension and ‘Outward-inward’ dimension. 2. As the multi-dimension map of this study has much space, it suggested that the scope of consumption emotions related to apparel products was more limited than those related to general situations and products. 3. The structure of consumption emotions in relation to apparel performances appeared to be bisected, while those related to usage situations showed relatively to be dispersed. 4. Although Pleasant-unpleasant dimension was consistent with results of prestudies, the dimensions of ‘Relaxed-tense’ and ‘Outward-inward’ were newly confirmed as the dimensions of consumption emotions related to apparel products. Therefore, consumer's consumption emotions of apparel products were composed of three dimensions, tended to be more limited than those of general consumption situations and products, and differentiated across apparel performances, usage situation, and specific products.

• The Journal of Asian Finance, Economics and Business
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• 제6권1호
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• pp.177-185
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• 2019

Service quality is still a new concept to those who works in shipping lines services since it has not been identified as a mandatory factor to increase competitiveness. Most carriers are currently offering services at the same level of price, transit time, equipment, etc. Thus offering a high quality service is the best way for a carrier to differentiate itself from its competitors in the market. The research aims to conduct an assessment on service quality at Wan Hai Lines (WHL) outbound services based on the SERVQUAL model, form of dimension-by-dimension analysis. This study was based on a survey of 135 people. The outcome is the service quality of WHL outbound services can be identified by three dimension(s): Empathy and Responsiveness, Assurance, and Reliability. It would help management to have an overall picture about the current service quality, and to find solutions to improve service quality following the recommendations. WHL managers need to recognize that "Reliability" has the strongest influence on customers' expectations, then come "Empathy and Responsiveness" and "Assurance". Therefore, board of managers should spend time looking carefully at each of the three dimensions, especially for the biggest gap between perceptions and expectations of three dimensions as well. Then the recommendations were raised.

• 무역학회지
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• 제46권2호
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• pp.75-92
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• 2021

There is increasing awareness in the international alliance literature that the firm performance effects of the alliance portfolio go beyond the effects of the individual alliances. I enrich this nascent perspective by developing a alliance portfolio composition framework based on the alliance portfolio dimensions - underpinned by the simultaneity of quantitative and qualitative factors in international portfolio - that enhances firms' financial performance. This paper assesses the impact on firm performance of composing the alliance dimension within a firm's international alliance portfolio. In an unbalanced panel data analysis with fixed effects of the performance of 502 firms operating in the Korean manufacturing industry during 2011-2017, I test whether firm's three dimension of international alliance portfolio affect on firm financial performance. I find that the intensity of international alliance have significantly positive effect on the firm performance. And following the moderating analysis of three portfolio dimension-functional, relational, and attribute, all of each three international alliance portfolio has positive moderating effects on the relationship between the alliance intensity and firm performance. These results indicate that firms should consider and form simultaneous approaches to exploit the international alliance based on the alliance portfolio dimensions with intensity of alliance portfolio.

• 한국디자인학회:학술대회논문집
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• 한국디자인학회 2005년도 춘계 학술발표대회 논문집
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• pp.222-223
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• 2005

• 대한전기학회:학술대회논문집
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• 대한전기학회 2003년도 학술회의 논문집 정보 및 제어부문 B
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• pp.507-510
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• 2003

In this paper, optical sensor system using PSD(Position Sensitive Detection) is proposed to obtain the three dimensional position of moving markers attached to human body. To find the coordinates of an moving marrer with stereo vision system, two different sight rays of an moving marker are required. Usually, those are acquired with two optical sensors synchronized at the same time. PSD sensor is used to measure the position of an incidence light in real-time. To get the three-dimension position of light source on moving markers, a conventional camera calibration method are used. In this research, we realized a low cost motion capture system. The proposed system shows high three-dimension measurement accuracy and fast sampling frequency.