• 대한수학회논문집
• /
• 제38권4호
• /
• pp.983-992
• /
• 2023

Let A be a ring and 𝓙 = {ideals I of A | J(I) = I}. The Krull dimension of A, written dim A, is the sup of the lengths of chains of prime ideals of A; whereas the dimension of the maximal spectrum, denoted by dim _𝓙A, is the sup of the lengths of chains of prime ideals from 𝓙. Then dim _𝓙A ≤ dim A. In this paper, we will study the dimension of the maximal spectrum of some constructions of rings and we will be interested in the transfer of the property J-Noetherian to ring extensions.

• 대한수학회지
• /
• 제58권6호
• /
• pp.1311-1325
• /
• 2021

One says that a ring homomorphism R → S is Ohm-Rush if extension commutes with arbitrary intersection of ideals, or equivalently if for any element f ∈ S, there is a unique smallest ideal of R whose extension to S contains f, called the content of f. For Noetherian local rings, we analyze whether the completion map is Ohm-Rush. We show that the answer is typically 'yes' in dimension one, but 'no' in higher dimension, and in any case it coincides with the content map having good algebraic properties. We then analyze the question of when the Ohm-Rush property globalizes in faithfully flat modules and algebras over a 1-dimensional Noetherian domain, culminating both in a positive result and a counterexample. Finally, we introduce a notion that we show is strictly between the Ohm-Rush property and the weak content algebra property.

• Journal of the Korean Data Analysis Society
• /
• 제20권6호
• /
• pp.2711-2719
• /
• 2018

When an observable is described by a single value, the statistic significance may be estimated by construction of null distribution using permutation and counting the portion of it that exceeds the observed value by chance. Genome-wide association study usually focuses on the association measure between a single or interacting genotypes with a single phenotype. However investigation of common genotypes associated simultaneously on multiple phenotypes may involve the observables that should be described with multiple numbers. Statistical significance for such an observable would involve null distribution in multiple dimensions. In this study, extension of the p-value estimation process using null distribution in one dimension has been sought that may be applicable to two dimensional case. Comparison of the position of points within the set of points they form has been proposed to use a positioning parameter inspired by the extension of the Kolmogorov-Smirnov statistic to two dimensions.

• 전자공학회논문지S
• /
• 제34S권10호
• /
• pp.120-131
• /
• 1997

This paper prsents a new method that automatically recognizes the dimension lines (consisting of shape lines, tail lines and extension lines) from the mechanical drawings. In the proposed method, the object and closed-loop symbols are separated from the character-free drawings. Then the object lines and interpretation lines are vectorized by using several techniques such as thinning, line-vectorization, and vector-clustering. Finally, after recognizing arrowheads by using pattern matching, we recognize dimension lines from interpretation lines by using arrohead's directional vector and centroid. By using the methods of geometric modeling and mathematical operation, the proposed method readility recognizes the dimension lines from complex drawings. Experimental resuls are presented, which are obtained by applying the proposed method to drawings drawn in compliance with the KS drafting standard.

• 대한수학회논문집
• /
• 제35권2호
• /
• pp.653-666
• /
• 2020

In this paper, when G is a connected and simply connected nilpotent Lie group of dimension less than or equal to four, we study the uniform lattices Γ of G up to isomorphism and then we study the structure of the automorphism group Aut(Γ) of Γ from the viewpoint of splitting as a natural extension.

• 대한수학회보
• /
• 제49권1호
• /
• pp.205-211
• /
• 2012

Let R be a graded Noetherian domain and A a graded Krull overring of R. We show that if h-dim $R\leq2$, then A is a graded Noetherian domain with h-dim $A\leq2$. This is a generalization of the well-know theorem that a Krull overring of a Noetherian domain with dimension $\leq2$ is also a Noetherian domain with dimension $\leq2$.

• Communications for Statistical Applications and Methods
• /
• 제28권5호
• /
• pp.553-562
• /
• 2021

Directional regression (DR; Li and Wang, 2007) is well-known as an exhaustive sufficient dimension reduction method, and performs well in complex regression models to have linear and nonlinear trends. However, the extension of DR is not well-done upto date, so we will extend DR to accommodate multivariate regression and large p-small n regression. We propose three versions of DR for multivariate regression and discuss how DR is applicable for the latter regression case. Numerical studies confirm that DR is robust to the number of clusters and the choice of hierarchical-clustering or pooled DR.

• Industrial Engineering and Management Systems
• /
• 제13권4호
• /
• pp.454-462
• /
• 2014

Retention of possible churning customer is one of the most important issues in customer relationship management, so companies try to predict churn customers using their large-scale high-dimensional data. This study focuses on dealing with large data sets by reducing the dimensionality. By using six different dimension reduction methods-Principal Component Analysis (PCA), factor analysis (FA), locally linear embedding (LLE), local tangent space alignment (LTSA), locally preserving projections (LPP), and deep auto-encoder-our experiments apply each dimension reduction method to the training data, build a classification model using the mapped data and then measure the performance using hit rate to compare the dimension reduction methods. In the result, PCA shows good performance despite its simplicity, and the deep auto-encoder gives the best overall performance. These results can be explained by the characteristics of the churn prediction data that is highly correlated and overlapped over the classes. We also proposed a simple out-of-sample extension method for the nonlinear dimension reduction methods, LLE and LTSA, utilizing the characteristic of the data.

• 한국의류학회지
• /
• 제21권7호
• /
• pp.1124-1138
• /
• 1997

This study intended to investigate the concept of Clothing Involvement and Brand and to provide useful basic data for building on affective brand strategy. The purpose of this study is as follows: first, It is to measure the result of Brand Extension attitudes and Brand Extension items by clothing involvement (high involvement/low involvement). Second, It is to classify the factors of Clothing Involvement which suggested in theoretical research and to clarify correlation between clothing involvement factor and brand evaluation, brand extension attitudes. Third, It is to investigate the affect that clothing involvement, demographic variable and brand type on Brand Extension Evaluation. Subjects of this study were the adult women in Seoul, who were extracted by sampling randomly during the fall of 1995. Questionnaire was used as major method of gathering data. They were analyzed by the SAS method such as Frequency, Anova, Duncan, Correlation, multiple regression, Factor analysis. Main result of this study were as follows : 1. In brand extension attitude evaluation by high-involve group and low-involve group, quality, reputation and buying intension of brand extension attitudes showed significant difference. B brand extension attitudes and items of high-involve group was high compare to low-involve stoup. High-involve group evaluated watch, underwear, shoes and stocking of extension items highly, and there is no involvement difference of perfume, parasol, cushion. 2. In order to classify the dimension of Clothing Involvement, it was carried out factor analysis. 1 found that Clothing Involvement was composed of 4 factors, namely, interest - fashion.perceived risk symbolism. Correlation between clothing involvement and brand extension attitude was as followed; Interest factor of clothing involvement was correlated the existing brand attitude. Brand preference of the existing brand attitude was related the image of brand extension attitude, interest of advertising was the quality and the reputation-image was the buying intension. 3. For evaluation of a factor influenced on Brand Extension, it was produced multiple -regression test. Demographic variables and brand types had some influence of Clothing Involvement and Clothing Involvement had on brand extension. 27% of interest, 26% of symbolism was explained by brand types and 15% of fashion, 6% of perceived risk was explained by brand types, demographic variables. And, 10% of brand extension was explained by interest, fashion and symbolism.

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