• Korean Journal of Mathematics
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• 제20권4호
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• pp.525-532
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• 2012

We study the extended quadratic residue code of length 24 over $\mathbb{Z}_3$ and its lifts to rings $\mathbb{Z}_{3^e}$ for all e including 3-adic integers ring. We completely determine the weight enumerators of all these lifts.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1992년도 봄 학술발표회 논문집
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• pp.47-52
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• 1992

The entire nonlinear behavior of reinforced concrete frames up to collapse, is analyzed by the displacement control method and the combined layered and nonlayered method. All of the rigidities of section are calculated approximately by a sum over all the layers for the layered method, are used the integral values over the cross section area for the nonlayered method. The spurious sensitivity to the chosen element size in the result of analysis by finite element method for the materials with strain-softening can be overcome by modifying the strain distribution based on the concept of fracture energy at plastic hinge considering the applied axial load.

• East Asian mathematical journal
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• 제30권3호
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• pp.259-270
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• 2014

For a generalized triangular matrix ring $$T=\[\array{R\;M\\0\;S}]$$, over rings R and S having only the idempotents 0 and 1 and over an (R, S)-bimodule M, we characterize all homomorphisms ${\alpha}$'s and all ${\alpha}$-derivations of T. Some of the homomorphisms are compositions of an inner homomorphism and an extended or a twisted homomorphism.

• 한국항해학회지
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• 제14권1호
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• pp.1-7
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• 1990

A theoretical model for the over-all ship's magnetism was developed, on the assumption that the magnetism of a three-island type vessel can be regarded as that of the prolate spheroidal magnetic body. Modelled values were determined by the simulation on the base of the theoretical analysis of the magnetic field around the above-mentioned magnetic body. The real values were made of the data observed from four different three-islands type vessels alongside the piers. The agreement between the modelled and real values was found to be accurate.

• 농촌지도와개발
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• 제16권4호
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• pp.939-965
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• 2009

The Machine Learning has been identified as a promising approach to knowledge-based system development. This study aims to examine the ability of machine learning techniques for farmer's decision making and to develop the reference model for using pig farm data. We compared five machine learning techniques: logistic regression, decision tree, artificial neural network, k-nearest neighbor, and ensemble. All models are well performed to predict the sow's productivity in all parity, showing over 87.6% predictability. The model predictability of total litter size are highest at 91.3% in third parity and decreasing as parity increases. The ensemble is well performed to predict the sow's productivity. The neural network and logistic regression is excellent classifier for all parity. The decision tree and the k-nearest neighbor was not good classifier for all parity. Performance of models varies over models used, showing up to 104% difference in lift values. Artificial Neural network and ensemble models have resulted in highest lift values implying best performance among models.

• 대한수학회보
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• 제51권1호
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• pp.253-266
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• 2014

Commutative rings in which every prime ideal is an intersection of maximal ideals are called Hilbert (or Jacobson) rings. We propose to define classical Hilbert modules by the property that classical prime submodules are intersections of maximal submodules. It is shown that all co-semisimple modules as well as all Artinian modules are classical Hilbert modules. Also, every module over a zero-dimensional ring is classical Hilbert. Results illustrating connections amongst the notions of classical Hilbert module and Hilbert ring are also provided. Rings R over which all modules are classical Hilbert are characterized. Furthermore, we determine the Noetherian rings R for which all finitely generated R-modules are classical Hilbert.

• 대한수학회논문집
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• 제9권4호
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• pp.933-944
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• 1994

Let $\pi : P \to S^4$ be a principal G-bundle over $S^4$ whose the structure group G is a compact, connected, simple Lie group. Since $\pi_3(G) = \pi_4 (BG) = Z$, we can classify the principal bundle $P_k$ over $S^4$ by the map $S^4 \to BG$ of degree k. Atiyah and Jones [2] showed that $C_k = A_k/g^b_k$ is homotopy equivalent to $\Omega^3_k G \simeq \Omega^4_k BG$ where $A_k$ is the space of the all connections in $P_k$ and $g^b_k$ is the based gauge group which consists of all base point preserving automorphisms on $P_k$. Here $\Omega^nX$ is the space of all base-point preserving continuous map from $S^n$ to X. Let $M_k$ be the space of based gauge equivalence classes of all connections in $P_k$ satisfying the Yang-Mills self-duality equations, which we call the moduli space of G instantons.

• 천문학회보
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• 제44권1호
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• pp.79.1-79.1
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• 2019

We present an algorithm for the fast computation of the general N-point spatial correlation functions of any discrete point set embedded within an Euclidean space of ${\mathbb{R}}n$. Utilizing the concepts of kd-trees and graph databases, we describe how to count all possible N-tuples in binned configurations within a given length scale, e.g. all pairs of points or all triplets of points with side lengths < rmax. Through benchmarking we show the computational advantage of our new graph-based algorithm over more traditional methods. We show that all 3-point configurations up to and beyond the Baryon Acoustic Oscillation scale (~200 Mpc in physical units) can be performed on current Sloan Digital Sky Survey (SDSS) data in reasonable time. Finally we present the first measurements of the 4-point correlation function of ~0.5 million SDSS galaxies over the redshift range 0.43< z <0.7. We present the publicly available code GRAMSCI (GRAph Made Statistics for Cosmological Information; bitbucket.org/csabiu/gramsci), under a GNU General Public License.

• 대한간호학회지
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• 제29권6호
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• pp.1179-1191
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• 1999

This study was conducted to identify appetite and nutritional status of 48 cancer patients who have been irradiated over 150$\textrm{cm}^2$ on chest or pelvic area over the three-month period. The data were gathered 3 phases, Each from initiation to completion of radiotherapy through the questionnaires of anorexia, the anthropometric and biochemical measures were used such as weight, TSF, MAC, MAMC, serum albumin and hemoglobin, TLC. Using SAS program, data were analyzed by percentage, Mean$\pm$SD, and two-way repeated measures ANOVA. The results were summarized as follows : 1. Eighty five percent(85%) of the subjects were aged from fifties to sixties. Cancers in the chest area occurred in 100% of men, 56% of the all subjects. The other 44% were pelvic cancer and 71% of the pelvic cancer occurred in women. 2. There were no significant differences in the appetite scores by all groups(characteristics). Changes of the appetite score over time were statistically significant by age, sex, cancer areas staging, treatment modality, and radiation dosage (F=4.0, p=.022; t=6.09, p=.003; t=4.90, p=.009; F=3.28, p=.042; t=5.04, p=.0084; t=4.76, p=.011). The appetite score on the 2nd phase (4 weeks after initiating radiotherapy) decreased from the 1st phase (initiating irradiation), and then increased on the 3rd phase (completing irradiation). 3. There were no significant differences in the body weight and MAMC by all characteristics, and no changes in the body weight and MAMC over time. However there were significant differences of TSF, MAC, level of hemoglobin, level of albumin, and TLC by all characteristics during the three phases. TSF of the men and the chest cancer were lower than those of the women and the pelvic cancer (t=73.20, p=.0001; t=22.91, p=.0001). And there was significant difference by cancer staging(F=3.19, p=.050). But there was no change in TSF over time. MAC of the men and the chest cancer were lower than those of the women and the pelvic cancer each(t=9.23, p=.004; t=17.85, p=.0001). But no change in MAC over time. Levels of hemoglobin had significant differences by age, sex and cancer areas; levels of hemoglobin of older than the fifties, men, and chest area were higher than those on the others(F=3.82, p=.029; t=21.75, p=.0001; t=8.71, p=.005). Levels of albumin were significant differences by sex and cancer areas; levels of albumin on women, and pelvic area were higher than those on the others(t=6.34, p=.015; t=15.23, p=.0003). While the levels of hemoglobin were changed over time, levels of albumin were not changed and within normal limit. TLC of the men was higher than women(t=5.05, p=.029). Changes in the level of hemoglobin over time were statistically significant according to sex, cancer areas, and radiation dosage(t=3.49, p=.035; t=3.36, p=.039; t=4.04, p=.021).

• Korean Journal of Mathematics
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• 제27권3호
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• pp.767-777
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• 2019

We present a new way of obtaining the complete factorization of $X^n-1$ for n = 15, 17, 19 over the 4-adic ring ${\mathcal{O}}_4[X]$ of integers and thus over the Galois rings $GR(2^e,2)$. As a result, we determine all cyclic codes of lengths 15, 17 and 19 over those rings. This extends our previous work on such cyclic codes of odd lengths less than 15.