• 한국치위생학회지
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• 제18권5호
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• pp.653-664
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• 2018

Objectives: The purpose of this study was to examine the association between two major oral diseases and cardiovascular diseases. Methods: Data from the 6th Korean National Health and Nutrition Examination Survey (2013-2015) were used. The study included 12,754 adults, aged ${\geq}19years$, who participated in the questionnaire survey of health related to hypertension, stroke, myocardial infarction, and angina pectoris as well as completed blood tests, anthropometry, and oral examination. Statistical analyses included complex sample frequency, complex sample general linear, complex sample cross-tabulation, and complex sample logistic regression analyses. Results: With respect to the number of Decayed-Missing-Filled-Teeth(DMFT ), patients with hypertension (DMFT 8.05), stroke (DMFT 8.66), and angina pectoris (DMFT 8.24) showed a DMFT score of >2, compared with those who did not have these diseases (p<0.05). Patients with hypertension, stroke, myocardial infarction, and angina pectoris presented an approximately 2.7, 3.5, 4, and 3 times higher incidence of periodontal diseases, respectively, than those who did not (p<0.05). Based on the analysis of the relationship between the number of DMFT and cardiovascular diseases, patients with cardiovascular diseases had a risk of 1.033 higher DMFT than those who did not (p<0.05). As per the analysis of the relationship between periodontal diseases and cardiovascular diseases, patients with cardiovascular diseases had a 2.969 higher risk of periodontaldiseasesthanthosewithout them (p<0.05). Conclusions: Two major oral diseases were found to be associated with cardiovascular diseases. Therefore, to prevent these major oral diseases in patients with cardiovascular diseases, oral hygiene management must be actively performed.

• Journal of Korean Biological Nursing Science
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• 제22권1호
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• pp.53-60
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• 2020

Purpose: This study used raw data from the fifth (2010-2012) Korea National Health and Nutrition Examination Survey (KNHANES) to assess the relationship between vitamin D level and glycemic control of diabetes, and to provide basic data about the use of vitamin D for preparation of a treatment plan for diabetes in South Korea. Methods: For this study, data of 1,713 diabetes from KNHANES (2010-2012) were used. The collected data were analyzed using SPSS 18.0 program, and complex sample frequency analysis, descriptive statistics, complex sample cross analysis, complex sample general linear regression, and complex sample logistic regression analysis were performed. Results: It was found that the poor glycemic control group among the diabetes subjects had significantly lower level of blood vitamin D than the good glycemic control group. Factors affecting glycemic control included drinking, vitamin D levels, hypertriglyceridemia, duration of diabetes, and treatment of diabetes. Also, diabetics with vitamin D deficiency or shortage showed 3.55- and 2.61-times higher odds ratios, respectively, to be diagnosed as the poor glycemic control group than diabetics without vitamin D deficiency or shortage. Conclusion: This study is significant because it provides rationale and basic data about the use of vitamin D for preparation of a treatment plan for diabetes in South Korea by assessing the dependence of glycemic control on the vitamin D level of diabetics. Additionally, future studies are necessary to determine the appropriate concentration of vitamin D for diabetes prevention and treatment to prevent the side effects of excessive supplementation.

• Journal of Korean Biological Nursing Science
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• 제23권2호
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• pp.100-109
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• 2021

Purpose: This study aimed to compare the differences in the prevalence of metabolic syndrome between menopausal women and women of childbearing age and to determine the risk of metabolic syndrome among women in each group depending on whether they eat alone. Methods: Data of 1,813 women from the seventh Korea National Health and Nutrition Examination Survey (2016) were used. The collected data were analyzed using SPSS 20.0, and complex sample frequency analysis, descriptive statistics, complex sample cross analysis, complex sample general linear regression, and complex sample logistic regression analysis were performed. Results: According to the results of the study, there was no difference in the prevalence and risk of metabolic syndrome according to the presence of companions during meals between women of childbearing age and post-menopausal women, but there was a difference in health behavior. In other words, women of childbearing age who ate alone had a lot of experience of drinking, and menopausal women who ate alone did not tend to make any efforts to control their weight and did not perform aerobic exercise. In particular, the negative health behavior of menopausal women who ate alone increased the risk of prevalence of metabolic syndrome. Conclusion: The findings indicate that, for women who eat alone, interventions to prevent metabolic syndrome should be differentiated before and after menopause. Therefore, it is suggested to offer an educational program to prevent metabolic syndrome in women of childbearing age as well as provide regular assessments to diagnose metabolic syndrome and health behavior improvement programs for menopausal women.

• Journal of the Korean Data and Information Science Society
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• 제21권4호
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• pp.669-679
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• 2010

지역교육청 수요자 만족도조사를 위한 표본설계는 경상남도의 2009년 경남지역교육청 고객만족도 조사의 표본크기에 기초하여 시 군별 지역교육청평가에 맞추어 설계하였다. 대도시의 구단위 지역 교육청과 달리 지방의 시 군 교육청은 학생수와 학교수, 학급당 학생수 등의 변동이 크다. 시간 비용 등을 고려하여 전체 표본크기를 작게 하면서도 각 시 군 교육청 평가에 필요한 최소표본수를 확보하도록 설계하였다. 경상남도는 10개의 시지역과 10개의 군지역을 가지고 있고, 학생수가 상대적으로 작은 군지역교육청 평가에 필요한 최소표본수를 확보하기위해 지역별 평가에 필요한 최소표본을 우선배분한 후, 나머지는 지역별 학급수에 비례배분하였고, 표본학교는 지역과 학교설립유형별로 층화하여 학급수에 비례하여 추출하였다. 표본학교 내에서 조사대상 학생은 2단집락추출하였다. 지역별 추출율의 상이함을 보정하기 위해 가중치를 산정하였다. 조사자료의 분석은 가중치를 적용하여 가중평균, 가중총합 등을 이용하며, 분산의 추정은 통계소프트웨어에서 제공하는 균형반복복제, 잭나이프, 선형화방법 등을 사용할 수 있다.

• 한국분말재료학회지
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• 제13권6호
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• pp.408-414
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• 2006

[ $MoSi_2$ ] alloys with Al, B or Nb were prepared by an advanced consolidation process that combined mechanical alloying with pulse discharge sintering (complex forming) to improve the mechanical properties. Their microstructure and mechanical properties were investigated. The $MoSi_2$ alloys fabricated by complex forming method showed very fine microstructure when compared with the sample sintered from commercial $MoSi_2$ powders. Alloys made from powders milled in Ar gas had fewer silica or alumina phases as compared to their counterparts sintered from powders milled in air. In densification of the sintered body, addition of B was more effective than Al or Nb. Both Victors hardness and tensile test indicated that the alloy fabricated by the complex forming method showed better properties than the sample sintered from commercial $MoSi_2$ powders. The Al added alloy sintered from the powders milled in air had the superior mechanical properties due to the suppression of $SiO_2$ and formation of fine $Al_2O_3$ particles.

• Journal of Information Processing Systems
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• 제16권3호
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• pp.530-540
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• 2020

In order to solve the problem of low tracking accuracy caused by complex noise in the fault diagnosis of complex nonlinear system, a fault diagnosis method of high precision cost reference particle filter (CRPF) is proposed. By optimizing the low confidence particles to replace the resampling process, this paper improved the problem of sample impoverishment caused by the sample updating based on risk and cost of CRPF algorithm. This paper attempts to improve the accuracy of state estimation from the essential level of obtaining samples. Then, we study the correlation between the current observation value and the prior state. By adjusting the density variance of state transitions adaptively, the adaptive ability of the algorithm to the complex noises can be enhanced, which is expected to improve the accuracy of fault state tracking. Through the simulation analysis of a fuel unit fault diagnosis, the results show that the accuracy of the algorithm has been improved obviously under the background of complex noise.

• Bulletin of the Korean Chemical Society
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• 제34권9호
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• pp.2737-2740
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• 2013

The layered $KTiNbO_5$ was successfully synthesized with titanium(IV) isopropoxide and niobium oxalate by a novel polymerized complex (PC) method. The morphology and structure of the as-prepared sample was characterized by means of High-Resolution Transmission Electron Microscope, powder X-ray diffraction, and Laser Raman Spectroscopy. The spectral response characteristic was recorded by using UV-vis Diffuse Reflectance Spectroscopy. Results show that $KTiNbO_5$ as-prepared by PC method presents an uniform morphology of nano-particles, the mean particle sizes is ca. 28 nm corresponding to the (002), and the crystal structure can be well indexed to the orthorhombic phase. The sample as-prepared by PC method has higher band gap energy than that of the sample prepared by a solid-state reaction method due to the quantum size effect.

• Korea-Australia Rheology Journal
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• 제11권4호
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• pp.313-320
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• 1999

The difficulties involved in measuring rheological characteristics of complex fluids are discussed. Possible measurement errors, related to the complex nature of the sample, are reviewed. They are explained in terms of the various physical and chemical mechanisms that can cause them. This leads to possible strategies and techniques for avoiding measurement errors and for obtaining useful structural information from rheological experiments on complex materials. Finally, future evolutions in rheometry are discussed.

• Structural Engineering and Mechanics
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• 제26권5호
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• pp.591-615
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• 2007

An improvement is introduced to solve the plane problems of linear elasticity by reciprocal theorem for orthotropic materials. This method gives an integral equation with complex kernels which will be solved numerically. An artificial boundary is defined to eliminate the singularities and also an algorithm is introduced to calculate multi-valued complex functions which belonged to the kernels of the integral equation. The chosen sample problem is a plate, having a circular or elliptical hole, stretched by the forces parallel to one of the principal directions of the material. Results are compatible with the solutions given by Lekhnitskii for an infinite plane. Five different orthotropic materials are considered. Stress distributions have been calculated inside and on the boundary. There is no boundary layer effect. For comparison, some sample problems are also solved by finite element method and to check the accuracy of the presented method, two sample problems are also solved for infinite plate.

• Journal of the Korean Data and Information Science Society
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• 제16권3호
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• pp.609-620
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• 2005

In the secondary data analysis for categorical data, situations often arise in which the estimated cell variances are available, but not the full matrix of variances. In this case researchers are often inclined to use Pearson-type test statistics for homogeneity. However, for a complex sample observed cell proportions are not distributed as multinomial and Pearson-type test statistic generally is not distributed asymptotically as chi-square distribution. This paper evaluates powers for Wald test and Pearson-type test and the first order corrected test of Pearson-type test for homogeneity. The resulting power curves indicate that as the misspecification effect increases, the amount of inflation of significance level and the loss of power Pearson-type test are getting more severe.