• Title/Summary/Keyword: representing measure

Search Result 210, Processing Time 0.023 seconds

A Study on the Service Quality of Korea Train Express (고속철도 서비스품질에 관한 연구)

  • Lee Hyung-seok
    • Journal of the Korean Society for Railway
    • /
    • v.9 no.1 s.32
    • /
    • pp.81-88
    • /
    • 2006
  • The purpose of this study is to verify the dimensions of service quality of Korea Train Express(KTX) and to compare the service quality of KTX with that of general train. The researcher consisted of initial 32 items representing eight-dimension and analyzed the final quality dimensions of KTX. The collected data of passenger of 226 was analyzed by statistical procedures such as the iterative sequence of computing Cronbach's a, corrected item-to total correlations, and factor analyses. Through the repeated statistical process to puritY the items, a final set of 26 items representing six district dimensions; tangibles, timely responsiveness, empathy, comfort, information access and safety. The Results of independent samples t-test showed that the mean scores of all the service quality dimensions of KTX except for comfort were higher than those of general train. This finding will provide the more appropriate instrument to measure the KTX service quality as well as to improve the passengers' perception of the service quality.

ON NONSINGULAR EMBRY QUARTIC MOMENT PROBLEM

  • Li, Chungji;Sun, Xiaoyun
    • Bulletin of the Korean Mathematical Society
    • /
    • v.44 no.2
    • /
    • pp.337-350
    • /
    • 2007
  • Given a collection of complex numbers ${\gamma}{\equiv}\{{\gamma}ij\}$ $(0{\leq}i+j{\leq}2n,\;|i-j|{\leq}n)$ with ${\gamma}00>0\;and\;{\gamma}ji=\bar{\gamma}ij$, we consider the moment problem for ${\gamma}$ in the case of n=2, which is referred to Embry quartic moment problem. In this note we give a partial solution for the nonsingular case of Embry quartic moment problem.

Complete Preordering of Alternatives by Metric Distance Meausre (거리측정척도에 의한 대안들의 전체적 유사순서 결정)

  • 김영겸;이강인;김진용;이진규
    • Journal of the Korean Operations Research and Management Science Society
    • /
    • v.19 no.1
    • /
    • pp.41-52
    • /
    • 1994
  • Imprecision of evaluation or lack of prior information about preference can be an obstacle for decision maker in representing his strict preference. Therefore, fuzziness of preference can take place, and in addition, intransitivity or incomparability of preference becomes the critical difficulty in making complete preorder of alternatives. In order to get better solution and to improve practical usufulness, MCDM should be established as a pseudo-criterion model that include fuzzy preference. In this paper, we suggest a pseudo-criterion model that can make complete preorder of alternatives by metric distance measure.

  • PDF

UNIVARIATE TRUNCATED MOMENT PROBLEMS VIA WEAKLY ORTHOGONAL POLYNOMIAL SEQUENCES

  • Seonguk Yoo
    • East Asian mathematical journal
    • /
    • v.40 no.1
    • /
    • pp.25-36
    • /
    • 2024
  • Full univariate moment problems have been studied using continued fractions, orthogonal polynomials, spectral measures, and so on. On the other hand, the truncated moment problem has been mainly studied through confirming the existence of the extension of the moment matrix. A few articles on the multivariate moment problem implicitly presented about some results of this note, but we would like to rearrange the important results for the existence of a representing measure of a moment sequence. In addition, new techniques with orthogonal polynomials will be introduced to expand the means of studying truncated moment problems.

Truncated Complex Moment Problem with Data in a Circle

  • Lee, Sang-Hun;Sim, Jung-Hui
    • Kyungpook Mathematical Journal
    • /
    • v.45 no.2
    • /
    • pp.241-247
    • /
    • 2005
  • Let ${\gamma}{\equiv}\left{{\gamma}_{ij}\right}(0{\leq}i+j{\leq}2n)$ be a collection of complex numbers with ${\gamma}_{00}>0$ and ${\gamma}_{ji}={\bar{\gamma}}_{ij}$. The truncated complex moment problem for ${\gamma}$ entails finding a positive Borel measure ${\mu}$ supported in the complex plane ${\mathbb{C}}$ such that ${\gamma}_{ij}={\int}{\bar{z}}^{i}z^jd{\mu}(z)(0{\leq}i+j{\leq}2n)$. We solve this truncated moment problem with data in a circle and discuss the behavior of data in an extended moment matrix.

  • PDF

Design of MEMS Resonator Array for Minimization of Mode Localization Factor Subject to Random Fabrication Error (랜덤 제조 오차를 고려한 모드 편재계수를 최소화하는 반복 배열 마이크로 공진기의 최적설계)

  • Kim, Wook-Tae;Lee, Chong-Won
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
    • /
    • 2005.05a
    • /
    • pp.840-845
    • /
    • 2005
  • This paper presents a robust optimal design method for a periodic structure type of MEMS resonator that is vulnerable to mode localization. The robust configuration of such a MEMS resonator to fabrication error is implemented by changing the regularity of periodic structure. For the mathematical convenience, the MEMS resonator is first modeled as a multi pendulum system. The index representing the measure of mode variation is then introduced using the perturbation method and the concept of modal assurance criterion. Finally, the optimal intentional mistuning, minimizing the expectation of the irregularity measure for each substructure, is determined for the normal distributed fabrication error and its robustness in the design of MEMS resonator to the fabrication error is demonstrated with numerical examples.

  • PDF

Design of MEMS Resonator Array for Minimization of Mode Localization Factor Subject to Random Fabrication Error (랜덤 제조 오차를 고려한 모드 편재계수를 최소화하는 반복 배열 마이크로 공진기의 최적설계)

  • Kim, Wook-Tae;Lee, Chong-Won
    • Transactions of the Korean Society for Noise and Vibration Engineering
    • /
    • v.15 no.8 s.101
    • /
    • pp.931-938
    • /
    • 2005
  • This paper presents a robust optimal design method for a periodic structure type of MEMS resonator that is vulnerable to mode localization. The robust configuration of such a MEMS resonator to fabrication error is implemented by changing the regularity of periodic structure For the mathematical convenience, the MEMS resonator is first modeled as a multi-pendulum system. The index representing the measure of mode variation is then introduced using the perturbation method and the concept of modal assurance criterion. Finally, the optimal intentional mistuning, minimizing the expectation of the irregularity measure for each substructure, is determined for the normal distributed fabrication error and its robustness in the design of MEMS resonator to the fabrication error is demonstrated with numerical examples.

The Clustering of Parts with Qualitative and Quantitative Quality Properties using λ-Fuzzy Measure (λ-퍼지측도를 사용한 질적, 양적혼합품질특성을 가진 부품의 군집화)

  • Kim, Jeong-Man;Lee, Sang-Do
    • Journal of Korean Society for Quality Management
    • /
    • v.24 no.1
    • /
    • pp.126-136
    • /
    • 1996
  • In multi-item production system, GT(Group Technology) is used effectively in order to cluster various parts into groups. GT is based on clustering parts which have similar features, and these features are classified into two properties, namely crisp(quantitative) feature and fuzzy(qualitative) feature. Especially, many difficult problems are often faced that have to evaluate the properties of parts with the crisp and fuzzy feature together. As the basis of determining the similarity of inter-parts, in this method, one aggregate value is calculated on each part. However, because the above aggregate value is only gained from simple additive weighted sum, there is one problem in this method that has been handled the combination effect of inter-parts. For these reasons, in this paper, a proposed method is suggested for representing combination effect in order to cluster parts that have crisp and fuzzy properties into groups using ${\lambda}$-fuzzy measure and fuzzy integral.

  • PDF

Development of The Screw Lead Measurement System (나사 리드 측정시스템 개발)

  • Choi, Jong-Guen;Choi, Hyeon-Cheol;Kim, Hyung-Sun
    • Transactions of the Korean Society of Machine Tool Engineers
    • /
    • v.16 no.5
    • /
    • pp.7-13
    • /
    • 2007
  • This study proposes a new screw measurement system that is capable of measuring the pitch or lead of a screw, which is one of the most important parameters representing the screw quality. There are various conventional methods for screw measurement including some mechanical and optical ones, but they can not be applied to measure the lead except the profiles or sizes. The newly suggested method is able to measure the pitch or lead directly. This is executed by scanning the thread with a digital probe while the target screw rotates. The devised measurement system is a integrated computer system which is composed of a stepping motor, a digital linear gauge and a chuck device for holding the measured screw. In order to operate the system effectively and conveniently, a computer program having graphical user interface facility is developed. Some experiments were done to prove the effectiveness of the system.