• Journal of Korean society of Dental Hygiene
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• v.22 no.5
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• pp.333-340
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• 2022

Objectives: This study aimed to confirm the association between cognitive function and oral health status in the elderly. Methods: In this study, 5,794 respondents, aged 55 or older, who had participated in the 7th aging research panel survey were used. Statistical analyses were performed using a complex samples cross-tabulation analysis, complex samples general linear model, and a complex sample multinomial logistic regression analysis. Results: After analyzing the cognitive function of the elderly according to their oral health conditions, it was found that suspicions of dementia (19.6%) and cognitive function decline (25.9%) were more common for those who wore dentures than for those who did not wear dentures (p<0.001). Compared to those who did not wear dentures, those who wore dentures were linked to a 1.665 times higher suspicion of dementia (p<0.001). In comparison, cognitive decline was 0.964 times lower when the number of natural teeth increased by 1, and it was 0.941 times lower when the oral health evaluation index for the elderly increased by 1 point (p<0.001). Conclusions: As a result of this study, it was confirmed that cognitive function and oral health status are related in the elderly. Therefore, systematic measures for oral health management and oral health promotion should be prepared in tandem with awareness of possible cognitive decline in the elderly.

• Journal of Information Processing Systems
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• v.16 no.3
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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.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2001.04a
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• pp.191-193
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• 2001

This paper presents the result of groundwater analysis in Changwon area and the characteristics of the groundwater properties. Changwon city conducted groundwater analysis at 551 sites in 1996 and 1997. The water quality is suitable as groundwater use at 466 sites (84.6 %) and exceeds maximum contaminant levels (MCLs) at 85 sites (15.4 %). Major contaminants are total bacteria, coliform and nitrate-N. DNAPLs, e.g. TCE and PCE are detected in the areas of industrial complex and residence. The detection of TCE and PCE is due to organic solvents from manufacturing companies. They are also derived from laundries, Photographer's studios, septic tanks, etc. In addition, fifty groundwater samples were analyzed. Iron, manganese, zinc, copper, lead, aluminum and fluorine are detected in nearly all the groundwater samples. The groundwaters shown on the Piper diagram mostly belong to Ca-HCO$_3$ type.

• Geophysics and Geophysical Exploration
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• v.7 no.1
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• pp.41-44
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• 2004

Measurements of streaming potential can provide a means for the detection and quantification of contaminants in groundwater prior to remediation. However, laboratory determinations of specific electrolyte properties are required for an adequate analysis of the hydraulic gradient in complex situations. Data obtained for the King River in Tasmania confirm a linear relationship linking streaming potential data and hydraulic gradients. Laboratory samples at low concentration (0.001M KCl) indicate values in the range 20-80 mV/cm of water pressure, while for higher concentrations (0.01M KCl) values are less than 25 mV/cm. Similar ion concentrations are observed in the King River, consistent with field correlations indicating values for streaming potential close to 15 mV/cm. In-situ fluid samples are required for more detailed analysis of local anomalies that may be associated with variations in recharge and migration of contaminants.

• Archives of Pharmacal Research
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• v.5 no.2
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• pp.71-77
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• 1982

Improvements in the analytical methodology used in the gas chromatographic/mass spectral analysis of phenolic compounds from cigarette smoke are described. For the direct analysis of crude samples, pyridine extraction and the glass capillary column GC was used for the separation of phenolics as trimethylsilyl derivativatives. The separations of cigarette smoke on Carbowax 20M and SE-54 wall coated open tubular columns are given. Improved methodology for the routine quantitation of the identified components using the computer-controlled multiple ion selection technique of MS presented. Considerations pertaining to routine analyses of a multitude of complex smoke samples are also discussed.

• Journal of the Korean Chemical Society
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• v.44 no.3
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• pp.207-211
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• 2000

We have studied on the determination of Ni(II) using APDC as a complexing agent in Tween80 micellar medium. The absorption spectrum of Ni(PDC)$_2$ complex in Tween80 medium was better defined and more sensitive than that in chloroform Ni(PDC)$_2$ complex was very stable at pH 7.0 and up to 100 minutes, and could be quantitatively chelated when APDC was added to over 10 times moles of Ni(II). The optimum concentration of Tween80 was 0.1%. The calibration curve of Ni(PDC)$_2$ complex with good linearity(R$^2$=0.9955) was obtained in 0.1% Tween80 medium. The detection limit and the determination limit were 0.09 ${\mu}g$/mL and 0.28 ${\mu}g$/mL, respectively. This technique was applied to the analysis of Suwon stream water samples, and about l00% of recoveries were obtained from the spiked samples. Although the formation of Ni(PDC)$_2$ complex was interfered by various metal ions, this technique could be applied to the practical determination of Ni(II).

• Journal of The Korea Institute of Healthcare Architecture
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• v.24 no.4
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• pp.17-25
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• 2018

Purpose: Korean society is undergoing the rapid increase and poverty of elderly population. Therefore, the appropriate supply and planning of public rental housing for the low-income elderly is more important. The purpose of this study is to present the basic data for the study and planning of the elderly housing complex by analyzing the cognitive characteristics of the elderly residing in the rental housing. Methods: A questionnaire survey was conducted to identify health characteristics of the elderly living in the 'Gongreung SH Apartment'. 100 random samples were collected and 82 valid samples were analysed. Statistical analysis was performed using Excel and R for the age, sex, health, outdoor walking frequency and characteristics of Cognitive map of the elderly. Results: The characteristics of cognitive map were classified into point shapes and linear shapes. The linear group was lower in average age than the point group and tended to draw the map wider. The wider the map was, the more the number of elements in cognitive map was. The number of elements on the cognitive map decreased as respondents' age increased. On the other hand it was not related to residence period and gender of the elderly. Implication: The cognitive extent of the residential environment tends to decrease with age. Men's cognitive range is wider than women's. There is no corelation between the number of cognitive elements and cognitive map type. Men tend to have a systematic image of city, whereas women focus on relational and social urban factors. For sustainable apartment complex design, various characteristics of the group including men and women, different age and different health status should be considered.

• Bulletin of the Korean Chemical Society
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• v.30 no.5
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• pp.1026-1030
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• 2009

A novel Schiff base ligand (N, O system) 5-methoxy-2-phenyliminomethylphenol ($5-CH_3O-PMP$) was synthesized. Using the synthesized ligand as a fluorescent reagent, a fluorometric method was developed for the quantitative analysis of Al(III) ion. The quantitative analysis of Al(III) ion was performed by making the complex compound between Al(III) ion and $5-CH_3O-PMP$ in ethanol-water solution (85/15, v/v, pH 6.2). The excitation wavelength (${\lambda}em$) of the complex compound was 397 nm while the emmision wavelength (${\lambda}em$) was 498 nm. The quantitative analysis of Al(III) ion was carried out by estimating the fluorescence intensity. The various calibration curves were used for the quantitative analysis in the range of 0.27$\sim$27 ng/mL Al(III) ion concentrations. The detection limit was 0.027 ng/mL. Using the fluorometric method developed in this study, satisfying results were obtained from various samples such as tap water, hot spring water, river water, sea water and waste water, which contained considerable amounts of interfering ions.

• Bulletin of the Korean Chemical Society
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• v.25 no.5
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• pp.647-651
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• 2004

Partial Least Squares (PLS) calibration performance has been systematically investigated by changing spectral resolutions of near-infrared (NIR) spectra. For this purpose, synthetic samples simulating naphtha were prepared to examine the calibration performance in complex chemical matrix. These samples were composed of $C_6-C_9$ normal paraffin, iso-paraffin, naphthene, and aromatic hydrocarbons. NIR spectra with four different resolutions of 4, 8, 16, and 32$cm^{-1}$ were collected and then PLS regression was performed. For PLS calibration, five different group compositions (such as total paraffin content) and six different pure components (such as benzene concentration) were selected. The overall results showed that at least 8$cm^{-1}$ resolution was required to resolve the complex chemical matrix such as naphtha. It was found that the influence of resolution on the PLS calibration was varied by the spectral features of a component.

• Journal of Korean society of Dental Hygiene
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• v.22 no.1
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• pp.29-36
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• 2022

Objectives: This study aimed to examine the association between age at menarche and two major oral diseases. Methods: Data from the 7th Korean National Health and Nutrition Examination Survey (2016-2018) were used. The participants included girls and women aged 12 years and above. Thedataofa total of 7,420 participants were analyzed. Statistical analyses were performed using complex samples cross-tabulation analysis and complex samples general linear model. Results: The average age at menarche of those aged 12 to 80 years was 13.81 years. The age at menarche was found to be associated with decayed-missing-filled teeth (DMFT) (p<0.05). When the age at menarche was nine years, DMFT was 4.20 when it was 19 years, DMFT was 10.80. The age at menarche was found to be associated with periodontal tissue state (p<0.05). The group with early menarche age had healthier periodontal tissues (17.1%), whereas the group with late menarche age had more unhealthy periodontal tissues (17.9%) (p<0.001). Conclusions: The age at menarche was associated with two major oral diseases. Therefore, it is necessary to provide women with oral hygiene care and oral health education to prevent major oral diseases before their secondary sex characteristics appear.