• Journal of the Korean Mathematical Society
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• v.55 no.6
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• pp.1359-1380
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• 2018

In this paper, we prove that if a metric measure space satisfies the volume doubling condition and the Hardy type inequality with the same exponent n ($n{\geq}3$), then it has exactly the n-dimensional volume growth. Besides, three interesting applications of this fact have also been given. The first one is that we prove that complete noncompact smooth metric measure space with non-negative weighted Ricci curvature on which the Hardy type inequality holds with the best constant are isometric to the Euclidean space with the same dimension. The second one is that we show that if a complete n-dimensional Finsler manifold of nonnegative n-Ricci curvature satisfies the Hardy type inequality with the best constant, then its flag curvature is identically zero. The last one is an interesting rigidity result, that is, we prove that if a complete n-dimensional Berwald space of non-negative n-Ricci curvature satisfies the Hardy type inequality with the best constant, then it is isometric to the Minkowski space of dimension n.

• The Journal of Engineering Geology
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• v.3 no.2
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• pp.149-165
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• 1993

Nowadays, the field hydraulic test is still an only method to evaluate groundwater characteristics in subsurface. The results of hydraulic test are very important for the concept model of fracture hydrogeology as well as the geometric pattern of fractures. The hydraulic tests performed in Korea are generally analysed under such assumption as steady radial flow in homogeneous aquifer or along simple geometry of fractures. Also the transmissivity measured in a fixed interval length is equivalent to a sum of individual fracture transmissivities in test legth. The boundary effects of weH hydraulics and the geometry of flow paths are hardly obtained from the test results analysed by a steady flow method. To circumvent this problem, the flow dimensional analysis was attempted from the results of constant pressure injection test carried out in a fractured granite area. A comparison of the hydraulic conductivity values from the transient and steady analysis shows that the latter is about a factor of 2~3 higher than the former. However, it was possible to analyse a flow dimension of each test interval from flow rate variation with time. The upper part of the bedrock(<10m deep) indicates an open boundary and the flow dimension shows nearly steady states, while the lower part of the bedrock(>25m deep) is characterized as sublinear flow dimension with a dosed boundary. In one of the test sections(15m deep), the flow dimension was changed from linear flow to spherical flow. From the experience of this study, one of the immediate problems to be solved is to enhance the field testing equipments, i.e., an accurate flowmeter with autorecording and a pressure detecting device to be able to install in the test section.

• The Journal of Churna Manual Medicine for Spine and Nerves
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• v.10 no.1
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• pp.63-74
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• 2015

Objectives : This study is planned to classify correlation between thoracic kyphosis angle and prevalence of cervical intervertebral disc. Methods : We Measured the thoracic kyphosis angel of the 110 men and 179 women patients with neck pain in 00 Korean Medicine Hospital. We use Cobb's angle method and Thoracic cage dimension method for measuring the thoracic kyphosis. And We use Magentic Resonance Imaging(MRI) for classifying the patient who has cervical intervertebral disc or not. Results : 1. There was statistical difference on the thoracic cage dimension with gender(P<0.001), while there was no statistical difference on Cobb's angle with gender(P=0.882). 2. Age and thoracic cage dimension(r=0.383) is statistically more correlative than age and cobb's angle(r=-0.59). Conclusions : 1. Thoracic cage dimension and gender, Thoracic cage dimension and age were statistically concerned on patient who has neck pain, while Cobb's angle had no statistical correlation with age and gender. 2. There was no statistical difference on the Cobb's angle and Thoracic cage Dimension between patient who has one or more cervical disc herniation(Protrusion disc, Extrusion disc) segment and patient who didn't have cervical disc herniation(Protrusion disc, Extrusion disc) segment.

• Journal of the Korean Society of Costume
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• v.50 no.5
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• pp.91-102
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• 2000

The purposes of this study are to determine dimension of apparel expectations. performances and service quality of home shopping and thereby, to analyze effect of apparel commodities dimension (expectations, performances, disconfirmation and satisfaction) and service dimension (service quality and satisfaction) on repurchase intention. The subject were 351 women in the age of twenty to sixty years old who live in Seoul and the suburban of Seoul. The results of this study can be summarized as follows : 1. It was found that home shopping consumers' expectation and performance with apparel commodities were classified 3 factors. On the other hand, the dimensions of service quality were found to have such 3 factors as convenience reliability, personal factor, and apparel one. 2. More frequent users of home shopping scored more on average than less frequent users in terms of service quality, service satisfaction and intention of repurchase. On the other hand, the cable TV users scored more on average than catalogue users In terms of service quality and intention of repurchase. 3. It was found that consumers' intention of repurchase of home shopping were affected by such variables as discofirmation and satisfaction with apparel commodities, service quality and service satisfaction. While less frequent users were affected by disconfirmation and service quality, more frequent users were affected by such variables as apparel commodities satisfaction, service quality and service satisfaction. Meanwhile, both cable TV and catalogue users were found to be affected by service quality and service satisfaction.

• Journal of Institute of Control, Robotics and Systems
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• v.7 no.5
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• pp.445-453
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• 2001

The multiple targets tracking problem has been one of the main issues in the radar applications area in the last decade. Besides the standard Kalman filtering, various methods including the variable dimen-sion filter, input estimation filter, interacting multiple model(IMM) filter, dederated variable dimension filter with input estimation, etc., have proposed to address the tracking and sensor fusion issues. In this pa- per, two existing tracking algorithm, i.e, the IMM filter and the variable dimension filter with input estima-tion(VDIE), are combined for the purpose of improving the tracking performance for maneuvering targets. To evaluate the tracking performance of the proposed algorithm, three typical maneuvering patterns, i.e., waver, pop-up, and high-diver motions, are defined and are applied to the modified IMM filter as well as the standard IMM filter. The smaller RMS tracking errors, in position and velocity, of the modified IMM filter than the standard IMM filter are demonstrated though computer simulations.

• Journal of the Korean Society for Precision Engineering
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• v.15 no.12
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• pp.226-235
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• 1998

This study proposes the analysis and evaluation of method of time series of ultrasonic signal using the chaotic feature extraction for ultrasonic pattern recognition. The features are extracted from time series data for analysis of weld defects quantitatively. For this purpose, analysis objectives in this study are fractal dimension, Lyapunov exponent, and strange attractor on hyperspace. The Lyapunov exponent is a measure of rate in which phase space diverges nearby trajectories. Chaotic trajectories have at least one positive Lyapunov exponent, and the fractal dimension appears as a metric space such as the phase space trajectory of a dynamical system. In experiment, fractal(correlation) dimensions and Lyapunov exponents show the mean value of 4.663, and 0.093 relatively in case of learning, while the mean value of 4.926, and 0.090 in case of testing in slag inclusion(weld defects) are shown. Therefore, the proposed chaotic feature extraction can be enhancement of precision rate for ultrasonic pattern recognition in defecting signals of weld zone, such as slag inclusion.

• Journal of the Korean Society of Clothing and Textiles
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• v.35 no.6
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• pp.700-711
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• 2011

The purposes of the study were to identify the online service attributes that contribute to online consumer experiences of satisfaction, service failure, and service recovery and to examine whether differences exist in these attributes between U.S. and Korea. E-A-S-QUAL provided a useful framework for the study. Focus group interviews and web surveys were conducted by utilizing college students in both countries. No significant cultural differences were found in online service dimensions of service satisfaction. Personalization was the most frequently mentioned online service dimension of service satisfaction both in the U.S. and Korea. The findings showed significant cultural differences in terms of online service dimensions responsible for service failure and recovery. For Korean consumers, merchandising was one of the key online service dimensions of service failure, while efficiency was the important service dimension resulting in service failure for the U.S. consumers. In addition, for U.S. consumers, efficiency and personalization were the two most frequently mentioned service dimension for service recovery, while Korean consumers put more importance on the contact and information dimensions for service recovery. This study provided a comprehensive list of online service attributes important to online apparel retailing.

• Korean Journal of Human Ecology
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• v.22 no.1
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• pp.99-116
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• 2013

The purpose of this research is to explore the levels of luxury-frugality consumption of the female consumers and classify their types on luxury-frugality consumption behaviors. Total of 479 on-line questionnaires were surveyed nationwide for this research in February, 2012. Statistical analysis was achieved by using t-test, one-way ANOVA, Duncan's multiple range test, ${\chi}^2$, and Ward' hierarchical cluster analysis with a total of 479 questionnaires. The research results are summarized as follows: First, the overall luxury-frugality consumption average mark of female consumers was 2.44. Second, all surveyed female consumers were classified into four types based on the means scores of two dimension luxury-frugality consumption behaviors. A total 26.51% of female consumers belonged to Type 1 (named as luxury consumption group) where females scored high points on two dimension luxury consumption behaviors. Type 2 (named as excessive consumption group) occupied 32.78% and this group scored low on the luxurious consumption but high on the overconsumption. Type 3 (named as prefer prestige group) occupied 28.39% and this group scored low on the overconsumption but high on the luxurious consumption. Type 4 (named as frugal consumption group) had 12.32% of females whose scores of two dimension luxury-frugality consumption behaviors were low.

• Bulletin of the Korean Mathematical Society
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• v.55 no.2
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• pp.625-631
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• 2018

Let R be a commutative ring with identity and let R[x] be the collection of polynomials with coefficients in R. There are a lot of multiplications in R[x] such that together with the usual addition, R[x] becomes a ring that contains R as a subring. These multiplications are from a class of functions ${\lambda}$ from ${\mathbb{N}}_0$ to ${\mathbb{N}}$. The trivial case when ${\lambda}(i)=1$ for all i gives the usual polynomial ring. Among nontrivial cases, there is an important one, namely, the case when ${\lambda}(i)=i!$ for all i. For this case, it gives the well-known Hurwitz polynomial ring $R_H[x]$. In this paper, we completely determine the Krull dimension of $R_H[x]$ when R is a $Pr{\ddot{u}}fer$ domain. Let R be a $Pr{\ddot{u}}fer$ domain. We show that dim $R_H[x]={\dim}\;R+1$ if R has characteristic zero and dim $R_H[x]={\dim}\;R$ otherwise.

• Proceedings of the Materials Research Society of Korea Conference
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• 2011.05a
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• pp.6.1-6.1
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• 2011

Nanoscale block copolymer (BCP) patterns have been pursued for applications in sub-30 nm nanolithography. BCP self-assembly processing is scalable and low cost, and is well-suited for integration with existing semiconductor fabrication techniques. However, one of the major technical challenges for BCP self-assembly is limited tunability in pattern geometry, dimension, and functionality. We suggest methods for extending the degree of tunability by choosing highly incompatible polymer blocks and utilizing solvent vapor treatment techniques. Siloxane BCPs have been developed as self-assembling resists due to many advantages such as high etch-selectivity, good etch-resistance, long-range ordering, and reduced line-edge roughness. The large incompatibility leads to extensive degree of pattern tunability since the effective volume fraction can be easily manipulated by solvent-based treatment techniques. Thus, control of the microdomain size, periodicity, and morphology is possible by changing the vapor pressure and the mixing ratio of selective solvents. This allows a range of different pattern geometry such as dots, lines and holes and critical dimension simply by changing the processing conditions of a given block copolymer without changing a polymer chain length. We demonstrate highly extensive tunability (critical dimension ~6~30 nm) of self-assembled patterns prepared by a siloxane BCP with extreme incompatibility.