• Journal of Internet Computing and Services
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• v.9 no.1
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• pp.129-135
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• 2008

This paper presents a methodology to forecast KOSPI index by extracting fuzzy rules based on the neural network with weighted fuzzy membership functions (NEWFM) and the minimized number of input features using the distributed non-overlap area measurement method. NEWFM classifies upward and downward cases of KOSPI using the recent 32 days of CPPn,m (Current Price Position of day n for n-1 to n-m days) of KOSPI. The five most important input features among CPPn,m and 38 wavelet transformed coefficients produced by the recent 32 days of CPPn,m are selected by the non-overlap area distribution measurement method. For the data sets, from 1991 to 1998, the proposed method shows that the average of forecast rate is 67.62%.

• Communications of the Korean Mathematical Society
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• v.17 no.4
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• pp.577-581
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• 2002

The incidence matrices corresponding to a nil-algebra of finite index % can be used to determine the nilpotency. We find the smallest positive integer n such that the sum of the incidence matrices Σ$\_$p/$\^$p/ is invertible. In this paper, we give a different proof of the case that the nil-algebra of index 2 has nilpotency less than or equal to 4.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.34 no.4
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• pp.114-119
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• 2011

Process capability indices (PCls) have been widely used in manufacturing industries to provide a quantitative measure of process potential and performance. The previous studies have measured only one location on each part in the case of single variate. To calculate the reliable process capability, a couple of measuring locations on each part are required. In this paper, we propose a new system process capability index $SC_{pm}$ (m) which is the minimum value of the location PCls.

• Proceedings of the Korea Information Processing Society Conference
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• 2010.11a
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• pp.490-493
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• 2010

본 논문에서는 클러스터 측정(Cluster Measurement)과 유전자 알고리즘을 이용한 문서 클러스링 알고리즘을 제안한다. 유전자 알고리즘의 요소를 클러스터링에 대입하고 클러스터 측정을 적합도 함수에 대입하여 문서 클러스터링을 구현하였다. 성능 평가를 위하여 한국일보-20000/한국일보-40075 문서범주화 실험문서집합의 데이터 셋을 이용하였다. 클러스터링 성능 평가 결과 AS Index가 DB Index, RS Index 보다 좋은 성능을 보여준다. 또한 제안한 알고리즘이 K-means 클러스터링 알고리즘에 비교해 안정적으로 좋은 성능을 보여준다.

• Proceedings of the Optical Society of Korea Conference
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• 1990.02a
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• pp.237-241
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• 1990

A detailed theoretical and experimental study of k-na exchange in soda lime silicate glasses by RTP is presented. Concentration profiles i.e. index profiles are given by complementary error function added Gaussian function. The estimated diffusion coefficient is 1.54${\mu}{\textrm}{m}$2/min.

• Bulletin of the Korean Mathematical Society
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• v.53 no.6
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• pp.1893-1908
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• 2016

In this paper, we obtain some behaviours of theta sums of higher index for the $Schr{\ddot{o}}dinger$-Weil representation of the Jacobi group associated with a positive definite symmetric real matrix of degree m.

• Journal of the Korean Society for Industrial and Applied Mathematics
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• v.6 no.2
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• pp.43-52
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• 2002

By the use of Taylor's expansion formula with the integral remainder, an accurate approximation for the fiber refractive index profile is given.

• The Journal of Korean Medicine
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• v.29 no.3
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• pp.38-49
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• 2008

Objectives: Though overt thyroid dysfunction is well recognized to affect serum lipid profiles and obesity, there are conflicting reports on the effect of subclinical hypothyroidism on serum lipid profiles and obesity. In most reports, the definition of the upper normal limit of serum thyroid stimulation hormone (TSH) of 4.0${\sim}$5.0mU/L has been used to diagnose. However, recent studies have suggested a much lower TSH cut off with an upper limit of 2.5mU/L, because >95% of rigorously screened normal euthyroid volunteers had serum TSH values between 0.4 and 2.5mU/L. Therefore we defined subclinical hypothyroidism as a TSH level greater than 2.5mU/L. We sought to evaluate the correlations of subclinical hypothyroidism with obesity index and serum lipid profiles Methods: TSH levels were measured in 6190 men and 4223 women that participated in health examination and free T4, lipid profiles (total-cholesterol, triglyceride, LDL-C), and obesity index (body mass index, body fat, waist circumference, C-reactive protein) were also measured. Results: There were significant differences of triglyceride between subclinical hypothyroidism men and normal control subjects. In women, there were also significant differences of triglyceride and LDL-C between subclinical hypothyroidism and normal control subjects. Subclinical hypothyroidism women showed significant correlations of TSH with total cholesterol, LDL-C, triglyceride, and C-reactive protein. Subclinical hypothyroidism men and women with a TSH level 2.5${\sim}$4.0mU/L had significant differences of triglyceride and body fat. In men, there were significant differences of waist circumference andC-reactive protein. In women, there were significant differences of LDL-C. Conclusions: We have demonstrated correlations of subclinical hypothyroidism with serum lipid profiles and obesity index. These findings suggested that subclinical hypothyroidism people had an increased risk of dyslipidemia and obesity. Subclinical hypothyroidism people with a TSH level 2.5${\sim}$4.0mU/L may be also considered suspect since it may signal a case of evolving thyroid underactivity eligible to be prevented.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.19 no.4
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• pp.272-286
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• 2014

This study was performed to investigate the community structure and health assessment of macrobenthic assemblages in Cheonsu Bay, West Coast of Korea. Total species number was 224 and mean density was $1,940ind./m^2$, both of which were dominated by polychaete worms (111 species and $1,213ind./m^2$). In terms of density, the major dominant species were the bivalve Theora fragilis ($280{\pm}213ind./m^2$), the polychaetes Heteromastus filiformis ($254{\pm}218ind./m^2$), Lumbrineris longifolia ($216{\pm}41ind./m^2$), Mediomastus californiensis ($158{\pm}97ind./m^2$) and the amphipod Eriopisella sechellensis ($167{\pm}100ind./m^2$). As a result of community statistics (cluster analysis and nMDS ordination), the macrobenthic community structure was classified two major groups (inner and mouth of bay) and two stations (station 2 near Ganwol dyke in spring and summer). The Benthic Pollution Index (BPI) and AZTI's Marine Biotic Index (AMBI) were applied to assess the benthic ecological status. During the sampling periods, the BPI Index values varied between 11 (bad status) and 92 (high status). On the other hand, the AMBI Index values was ranged between 1.34 (good status) and 4.39 (poor status). In conclusion, in terms of the mean BPI and AMBI Index values, the ecological status of Cheonsu Bay were moderate status (ecotone stage) and good status, respectively.

• Communications of the Korean Mathematical Society
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• v.12 no.1
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• pp.59-67
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• 1997

Let $K'_M$ be the space of distributions on $R^m$ which grow no faster than $e^{M(kx)}$ for some k > 0 and an index function M(x) and $K'_M$ be the Fourier transform of $K'_M$. We establish the characterizations of the space $O_M(K'_m;K'_M)$ of multipliers in $K'_M$.