• Title/Summary/Keyword: Ratio of regression coefficients

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A Study on the Regional Factors Affecting the Death Rates of Cardio-Cerebrovascular Disease Using the Spatial Analysis (공간분석을 이용한 심뇌혈관질환 사망률에 영향을 미치는 지역요인 분석)

  • Park, Young Yong;Park, Ju-Hyun;Park, You-Hyun;Lee, Kwang-Soo
    • Health Policy and Management
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    • v.30 no.1
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    • pp.26-36
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    • 2020
  • Background: The purpose of this study was to analyze the relationship between the regional characteristics and the age-adjusted cardio-cerebrovascular disease mortality rates (SCDMR) in 229 si·gun·gu administrative regions. Methods: SCDMR of man and woman was used as a dependent variable using the statistical data of death cause in 2017. As a representative index of regional characteristics, health behavior factors, socio-demographic and economic factors, physical environment factors, and health care factors were selected as independent variables. Ordinary least square (OLS) regression and geographically weighted regression (GWR) were performed to identify their relationship. Results: OLS analysis showed significant factors affecting the mortality rates of cardio-cerebrovascular disease as follows: high-risk drinking rates, the ratio of elderly living alone, financial independence, and walking practice rates. GWR analysis showed that the regression coefficients were varied by regions and the influence directions of the independent variables on the dependent variable were mixed. GWR showed higher adjusted R2 and Akaike information criterion values than those of OLS. Conclusion: If there is a spatial heterogeneity problem as Korea, it is appropriate to use the GWR model to estimate the influence of regional characteristics. Therefore, results using the GWR model suggest that it needs to establish customized health policies and projects for each region considering the socio-economic characteristics of each region.

Evaluation and analytical approximation of Tuned Mass Damper performance in an earthquake environment

  • Tributsch, Alexander;Adam, Christoph
    • Smart Structures and Systems
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    • v.10 no.2
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    • pp.155-179
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    • 2012
  • This paper aims at assessing the seismic performance of Tuned Mass Dampers (TMDs) based on sets of recorded ground motions. For the simplest configuration of a structure-TMD assembly, in a comprehensive study characteristic response quantities are derived and statistically evaluated. Optimal tuning of TMD parameters is discussed and evaluated. The response reduction by application of a TMD is quantified depending on the structural period, inherent damping of the stand-alone structure, and ratio of TMD mass to structural mass. The effect of detuning on the stroke of the TMD and on the structural response is assessed and quantified. It is verified that a TMD damping coefficient larger than the optimal one reduces the peak deflection of the TMD spring significantly, whereas the response reduction of the main structure remains almost unaffected. Analytical relations for quantifying the effect of a TMD are derived and subsequently evaluated. These relations allow the engineer in practice a fast and yet accurate assessment of the TMD performance.

PARTIAL REPLACEMENT OF GRASS SILAGE WITH WHOLE-CROP CEREAL SILAGE FOR GROWING BEEF CATTLE

  • Raza, S.H.;Rowlinson, P.
    • Asian-Australasian Journal of Animal Sciences
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    • v.8 no.3
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    • pp.281-287
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    • 1995
  • A study was conducted to investigate the effect of different inclusion levels of urea treated whole-crop wheat silage (UWCWS) in grass silage based rations on the performance of growing beef cattle. The winter wheat (variety, Riband) was harvested (in the summer of 1991) at a dry matter proportion of 520 g/kg and treated with feed grade urea at the rate of 37 kg/tonne crop dry matter and preserved in a heavy duty plastic bag using a silo press. The urea treated whole crop wheat silage (UWCWS) was mixed with grass silage to replace 0.00 (S100), 0.33 (S33) and 0.67 (S67) parts of the forage dry matter and fed ad libitum in a cross over design to 18 Simmental X Holstein Friesian growing beef animals. Two energy sources {one high in starch, rolled barley (RB) and one high in digestible fibre, sugar beet pulp (SBP)} were fed to supply sufficient energy for the efficient use of nitrogen by the rumen micro-organisms. The data on DMIF (dry matter intake of forage), TDMI (total dry matter intake), DLWG (daily live weight gain), FCR (feed conversion ratio) were recorded and faecal samples were collected to determine the digestibility coefficients. Results revealed that with the inclusion of UWCW in the animals' diets the DMI of the forage was significantly increased (p < 0.05). The highest DMIF was found in the treatment "S33" ($6.28{\pm}0.25kg$) where 67% of the silage dry matter was replaced with the UWCW and the lowest value for DMIF was observed in the control treatment ($5.03{\pm}0.23kg$). The DLWG did not differ significantly between the treatments. However, treatment "S100" showed a trend towards a superior DLWG. Feed conversion ratio in the control treatment differed significantly from "S67" and "S33". The addition of the UWCW in the animals' diet resulted in the lower FCR There was no effect of type of energy supplement on any aspect of performance either overall or in interaction with grass silage: UWCWS ratio. The regression and correlation coefficients for DMIF (r = 5.22 + 0.0184x*), DLWG (r = $1.04-0.00086x^{NS}$) and FCR (r = 4.78 = 0.022x*) on the inclusion of UWCW in the diet were calculated. The effect of the inclusion of UWCW on the overall digestibility coefficients was significant (p < 0.05). The addition of the UWCWS in the diet decreased the digestibility of the DM, OM, ADF and NFE but effect on the protein digestibility was non significant. The results of present study suggests that a DLWG slightly over 1 kg can be achieved with UWCW during the store period (period in which animal performance targets are low especially during winter) and the prediction of ME was overestimated as the high intake of DM did not reflect in improved animal performance.

A Study on the Characteristics of Population Movement in South West Area of Kyonggi-do (경기 남서부지역의 인구특성 연구)

  • Choi, Sik-In
    • Journal of Agricultural Extension & Community Development
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    • v.11 no.1
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    • pp.83-93
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    • 2004
  • This paper investigated the characteristics of population structure and the determinants of population movement in the south west area of Kyonggi-do by grouping 9 cities in 3 categories and using Panel data of $1995{\sim}2001$. The major findings of this paper were identified as follows : 1) The population structure of regions was different to the stages of urbanization. The ratio of child and elder dependency was high in the rural regions and low in the urbanized regions. It was due to the movement of economically active population of $20{\sim}40$ aged groups, from rural regions to urban regions. This means that more productive segments of the rural population leave the country to the city. In addition. The ratio of male to female was higher in $20{\sim}40$ aged groups for rural regions. This suggested that young females moved from rural regions to urban regions more than young males in the process of industrialization. 2) Based in pooling regression, income was the most significant determinant that could explain the inter-regional and intra-regional movement of population for south west area studied, The next one was educational opportunity variable. The coefficients of income and education were 0.5, 0,7 for intra-regional migration and 0.01, 0.02 for interregional migration indicating that Todaro's hypothesis could be tested well rather than Tiebout' model for this area.

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Drying Equations of Sarcodon Aspratus (능이버섯의 건조 방정식)

  • Keum, D.H.;Ro, J.G.;Jung, T.Y.;Hong, S.R.;Park, K.M.;Kim, H.;Han, J.W.
    • Journal of Biosystems Engineering
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    • v.29 no.1
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    • pp.59-64
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    • 2004
  • This study was performed to determine drying equations of sarcodon aspratus. Drying tests for sarcodon aspratus were conducted in an experimental dryer equiped with an air conditioning unit. The drying tests were performed at three air temperatures of 30$^{\circ}C$, 40$^{\circ}C$ and 50$^{\circ}C$, and two relative humidities of 30% and 50%. Measured moisture ratio data were fitted with the selected four drying models(Page, Thompson, Lewis and simplified diffusion models) using stepwise multiple regression analysis. When the coefficients of determination and root mean square errors of moisture ratio were evaluated for four drying models, the Page model was found to fit adequately to all the drying test data with coefficient of determination of 0.9996 and RMSE of 0.00523.

Equilibrium Moisture Contents and Thin Layer Drying Equations of Cereal Grains and Mushrooms (I) - Thin Layer Drying Equations of Short Grain Rough Rice - (곡류 및 버섯류의 평형함수율 및 박층건조방정식에 관한 연구(I) -벼의 박층건조방정식 -)

  • 금동혁;박춘우
    • Journal of Biosystems Engineering
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    • v.22 no.1
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    • pp.11-20
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    • 1997
  • Thin layer drying tests of short gain rough rice were conducted in an experimental dryer equiped with air conditioning unit. The drying tests were performed in triplicate at three air temperatures of $35^circ$, $45^circ$, $55^circ$, and three relative humidities of 40%, 55%, 70%, respectively. Previously published thin layer equations were reviewed and four different models widely used as thin layer drying equations for cereal grains were selected. The selected four models were Pages, simplified diffusion, Lewis's and Thompson's models. Experimental data were fitted to these equations using stepwise multiple regression analysis. The experimental constants involved in tow equations were represented as a function of temperature and relative humidity of drying air. The results of comparing coefficients of determination and root mean square errors of miosture ratio for low equations showed that Page's and Thompsons models were found to fit adequately to all drying test data with coefficient of determination of 0.99 or better and root mean square error of moisture ratio of 0.025.

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Cross-sectional Study for Blood Metal Concentration in Patients with Herbal Medicine Intake

  • Park, Yeong-Chul;Lee, Sun-Dong
    • Journal of Society of Preventive Korean Medicine
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    • v.13 no.1
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    • pp.93-103
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    • 2009
  • Evidences from various countries suggest that toxic heavy metals in herbal medicine may constitute a serious health problem. In order to evaluate whether the toxic heavy metals caused by herbal medicine intake, blood samples collected from 222 patients taking herbal medicine were analyzed. In average levels of analyzed metals, $0.4{\sim}33.9%$ of total samples for 8 metals such as Cd, Co, Cu, Hg, Mn, Ni, Pb and Zn except Cr and Fe exceeded the upper limit for WHO reference value. In analysis of regression coefficients indicating the levels of metals increased or decreased after taking herbal medicine for one month, however, there were different aspects by intake types for herbal medicine. For example, the metals increased by taking decoction in blood samples were as follows; Cd and Pb whether Mn, Ni and Pb as increased metals were identified in the group taking pill and decoction(combined intake group). The odds ratio showing values higher than 1 indicating that people who take herbal medicine would have possibility higher for metal accumulation in blood than that from people who do not take herbal medicine. The metals showing the odds ratio higher than 1 were Hg and Ni in decoction group, and Cd and Hg in combined intake group. However, eight of the total, 10 metals showed the odds ratios lower than 1 by taking herbal medicine. Thus, this may explain the possible role of herbal medicine as a chelator for heavy metals in body.

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Determinants of Capital Structure of the Hospitality Industry (환대산업 기업의 자본구조결정요인)

  • Guahk, Seyoung
    • Industry Promotion Research
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    • v.5 no.3
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    • pp.31-36
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    • 2020
  • This study explores the determinants of capital structure of the hospitality industry such as hotels, lodging industry and tourism industry using financial data from 2000 to 2019. Several explanatory variables suggested by related theories and past studies were regressed with the dependent variable, debt ratio for the entire sample period, pre-crisis period and post-crisis period and the regression coefficients of the sales expenses, profitability and firm size were found to be statistically significantly negative. Especially the sign of the coefficient of the firm size was opposite to that of the manufacturing industry, which implies the uniqueness of the hospitality industry.

Multilevel Analysis of the Relationship Between Prescribing Institutions and Medication Adherence Among Patients With Hypertension and Diabetes in Korea

  • Haryeom Ghang;Juhyang Lee
    • Journal of Preventive Medicine and Public Health
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    • v.56 no.6
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    • pp.504-514
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    • 2023
  • Objectives: This study investigated the relationship between prescribing institutions and medication adherence among patients newly diagnosed with hypertension and diabetes. Methods: This study investigated patients with new prescriptions for hypertension and diabetes in Korea in 2019 with using data collected from general health screenings. A multilevel logistic regression model was applied to explore the relationship between patients' first prescribing institution and their medication adherence, defined as a medication possession ratio (MPR) over 80%. Results: The overall adherence rates were 53.7% and 56.0% among patients with hypertension and diabetes, respectively. The intra-class correlation coefficients were 13.2% for hypertension and 13.8% for diabetes (p<0.001), implying that the first prescribing institution had a significant role in medication adherence. With clinics as the reference group, all other types of hospitals showed an odds ratio (OR) less than 1.00, with the lowest for tertiary hospitals (OR, 0.30 for hypertension; 0.45 for diabetes), and the next lowest in health screening specialized clinics (OR, 0.51 for hypertension; 0.46 for diabetes). Among individual-level variables, female sex, older age, higher insurance premium level, and residing in cities were positively associated with adherence in both the hypertension and diabetes samples. Conclusions: This study showed that the prescribing institution had a significant relationship with medication adherence. When the first prescribing institution was a clinic, newly diagnosed patients were more likely to adhere to their medication. These results highlight the important role played by primary care institutions in managing mild chronic diseases.

Age Estimation by Radiological Measuring Pulp Chamber of Mandibular First Molar in Korean Adults

  • Jeon, Hye-Mi;Kim, Jin-Hwa;Heo, Jun-Young;Ok, Soo-Min;Jeong, Sung-Hee;Ahn, Yong-Woo
    • Journal of Oral Medicine and Pain
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    • v.40 no.4
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    • pp.146-154
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    • 2015
  • Purpose: The purpose of present study was to develop a method for assessing the chronological age of Korean adults based on the relationship between age and size of pulp cavity using dental radiographs of mandibular first molars. Methods: A total of 325 dental radiographs of Korean adults with known age and gender were selected for the study (199 males and 126 females) which were taken in the period between January 2009 and June 2014 at the Pusan National University Dental Hospital. The measurements were carried out on both orthopantomographs (OPGs) and intraoral periapical radiographs of mandibular first molar and the following ratios were calculated: pulp chamber floor height ratio (F/L), pulp chamber ceiling height ratio (R/L), and pulp chamber depth ratio (D/L). Results: The ratios of measurements on intraoral periapical images of mandible first molar generally produce more reliable data than the measurements on OPGs. The pulp chamber floor height ratio and pulp chamber thickness ratio showed significant correlation with age, whereas the pulp chamber ceiling height ratios showed weak correlation with age. It was found that the best correlations between the ratios and age were found for pulp chamber thickness ratios (r=-0.731 to -0.751). The multiple regression models were derived using 3 ratios that were significantly correlated with age. The determination coefficients ($R^2$) of the models ranged from 0.556 to 0.596. Conclusions: Our results indicate that the pulp chamber thickness and pulp chamber floor height in mandibular first molar are an age-dependent variable in adults which can be used to estimate age with reasonable accuracy. The higher image quality of dental radiographs will probably narrow the age estimation error and improve dental age estimation.