• Title/Summary/Keyword: regression function

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Soil Water Storage and Antecedent Precipitation Index at Gwangneung Humid-Forested Hillslope (광릉 산지사면에서의 선행강우지수와 토양저류량 비교연구)

  • Gwak, Yong-Seok;Kim, Su-Jin;Lee, Eun-Hyung;Hamm, Se-Yeong;Kim, Sang-Hyun
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.18 no.1
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    • pp.30-41
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    • 2016
  • The temporal variation of soil water storage is important in hydrological modeling. In order to evaluate an antecedent wetness state, the antecedent precipitation index (API) has been used. The aim of this article is to compare observed soil water storage with APIs calculated by widely used four equations, to configure the relationship between soil water storage and API by a regression model for one-year(2009), and to predict the soil water storage for the next two years(2010~2011). The soil water storage was evaluated from the observed soil moisture dataset in soil depths of 10, 30, 60cm at 21 locations by TDR measurement system for 3 years. As a result, API with the exponential function among the four equations can describe the variation of the observed soil water storage. Monthly optimized parameters of the API's equations seemed to be roughly related with the (potential) evapotranspiration (PET). Using revised monthly optimized parameters of APIs considering the seasonal pattern of PET, we characterize the relationship between API and the observed soil water storage for one year, which looks better than those of other researches.

A Study on the Development of Forest Fire Occurrence Probability Model using Canadian Forest Fire Weather Index -Occurrence of Forest Fire in Kangwon Province- (캐나다 산불 기상지수를 이용한 산불발생확률모형 개발 -강원도 지역 산불발생을 중심으로-)

  • Park, Houng-Sek;Lee, Si-Young;Chae, Hee-Mun;Lee, Woo-Kyun
    • Journal of the Korean Society of Hazard Mitigation
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    • v.9 no.3
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    • pp.95-100
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    • 2009
  • Fine fuel moisture code (FFMC), a main component of forest fire weather index(FWI) in the Canadian forest fire danger rating system(CFFDRS), indicated a probability of ignition through expecting a dryness of fine fuels. According to this code, a rising of temperature and wind velocity, a decreasing of precipitation and decline of humidity in a weather condition showed a rising of a danger rate for the forest fire. In this study, we analyzed a weather condition during 5 years in Kangwon province, calculated a FFMC and examined an application of FFMC. Very low humidity and little precipitation was a characteristic during spring and fall fire season in Kangwon province. 75% of forest fires during 5 years occurred in this season and especially 90% of forest fire during fire season occurred in spring. For developing of the prediction model for a forest fire occurrence probability, we used a logistic regression function with forest fire occurrence data and classified mean FFMC during 10 days. Accuracy of a developed model was 63.6%. To improve this model, we need to deal with more meteorological data during overall seasons and to associate a meteorological condition with a forest fire occurrence with more research results.

Factors Related to Physical Activities of Elderly with Hypertension between Urban and Rural Areas (고혈압 노인의 도농 간 신체활동참여 관련요인)

  • Paek, Hyun-Hee;Lee, Sok-Goo
    • Journal of agricultural medicine and community health
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    • v.40 no.2
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    • pp.62-71
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    • 2015
  • Objectives: This study was performed to find the differences in physical activity according to general characteristics and factors related to physical activity between the elderly over 65 with hypertension living rural and urban areas. Methods: This study included 681 participants (221 rural, 460 urban) with hypertension from The Fifth Korea National Health and Nutrition Examination Survey (KNHANES V). The collected data were analyzed through an $x^2$-test to examine the differences in physical activity and multiple logistic regression to assess factors related to physical activity between the elderly over 65 with hypertension living rural and urban areas. Results: The significant statistical factors related with physical activities for the urban hypertension group were education level, activities of daily living, and quality of life. However, the related factors for rural residents were activities of daily living and limitation of activity. Conclusions: The study results indicated that the factors that affected the level of physical activity revealed difference in case hypertension between the urban and rural groups. An awareness of the importance of physical activity will have a positive influence on improving the physical function and quality of life for elderly people with hypertension.

A Study on the Relationship of Infection Control Performance in a Long Term Care Hospital Caregivers (일개 지역 요양병원 간병인의 감염관리수행도 관련성 연구)

  • Hong, Na-Kyung;Kang, Kyung-Ja
    • Journal of Digital Convergence
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    • v.18 no.1
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    • pp.187-198
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    • 2020
  • The purpose of the study is to investigate infection management status of long term care hospitals and infection prevention knowledge of caregivers. This is descriptive study to investigate the factors affecting caregivers' infection control performance in long term care hospitals. The data collection period was from August, 2018, and a total of 197 caregivers from 8 long term care hospitals. The data analysis were done Win SPSS 20.0 with t-test, ANOVA, pearson's correlation coefficient, and hierarchical multiple regression analysis. Infection prevention knowledge was positively correlated with infection control performance (p=<.001). The factors influencing performance in a long term care hospital caregivers were over seventy years old (t=2.50, p=.013), eight-hour working time (t=-2.62, p=.010), nursing staffing First grades (t=2.48, p=.014), and infection prevention knowledge (t=2.96 p=.003), which explained 12.9% (F=6.70 p<.001). In summary, we recommend to develop infection education interventions to improve caregivers' infection control performance in long term care hospitals and to improve of the function in long term care hospitals.

Analysis and Prediction for Spatial Distribution of Functional Feeding Groups of Aquatic Insects in the Geum River (금강 수계 수서곤충 섭식기능군의 공간분포 분석 및 예측)

  • Kim, Ki-Dong;Park, Young-Jun;Nam, Sang-Ho
    • Journal of the Korean Association of Geographic Information Studies
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    • v.15 no.1
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    • pp.99-118
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    • 2012
  • The aim of this study is to define a correlation between spatial distribution characteristics of FFG(Functional Feeding Groups) of aquatic insects and related environmental factors in the Geum River based on the theory of RCC(River Continuum Concept). For that objective we had used SMRA(Stepwise Multiple Regression Analysis) method to analyze close relationship between the distribution of aquatic insects and the physical and chemical factors that may affect their inhabiting environment in the study area. And then, a probabilistic method named Frequency Ratio Model(FRM) and spatial analysis function of GIS were applied to produce a predictive distribution map of biota community considering their distribution characteristics according to the environmental factors as related variables. As a result of SMRA, the values of decision coefficient for factors of elevation, stream width, flow velocity, conductivity, temperature and percentage of sand showed higher than 0.5. Therefore these 6 environmental factors were considered as major factors that might affect the distribution characteristics of aquatic insects. Finally, we had calculated RMSE(Root Mean Square Error) between the predicted distribution map and prior survey database from other researches to verify the result of this study. The values of RMSE were calculated from 0.1892 to 0.4242 according to each FFG so we could find out a high reliability of this study. The results of this study might be used to develop a new estimation method for aquatic ecosystem with macro invertebrate community and also be used as preliminary data for conservation and restoration of stream habitats.

THE EFFECT OF MONOMER TO POWDER RATIO ON POLYMERIZATION SHRINKAGE-STRAIN KINETICS OF POLYMER-BASED PROVISIONAL CROWN AND FIXED PARTIAL DENTURE MATERIALS

  • Kim, Sung-Hun
    • The Journal of Korean Academy of Prosthodontics
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    • v.45 no.6
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    • pp.735-742
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    • 2007
  • Statement of problem. Although a number of previous investigations have been carried out on the polymerization shrinkage-strain kinetics of provisional crown and fixed partial denture (FPD) materials, the effect of the changes of liquid monomer to powder ratio on its polymerization shrinkage-strain kinetics has not been reported. Purpose. The purpose of this study was to investigate the influence of liquid monomer to powder ratio of polymer-based provisional crown and FPD materials on the polymerization shrinkage-strain kinetics. Material and methods. Chemically activated acrylic provisional materials (Alike, Jet, Snap) were investigated. Each material was mixed with different liquid monomer to powder ratios by volume (1.0:3.0, 1.0:2.5, 1.0:2.0, 1.0:1.5, 1.0:1.0). Time dependent polymerization shrinkage- strain kinetics of all materials was measured by the bonded-disk method as a function of time at $23^{\circ}C$. Five recordings were taken for each ratio. The results were statistically analyzed using one-way ANOVA and the multiple comparison Scheffe test at the significance level of 0.05. Trends were also examined by linear regression. Results. At 5 minutes after mixing, the polymerization shrinkage-strains of all materials ranged from only 0.01% to 0.49%. At 10 minutes, the shrinkage-strain of Alike was the highest, 3.45% (liquid monomer to powder ratio=1.0:3.0). Jet and Snap were 2.69% (1.0:2.0) and 1.58% (1.0:3.0), respectively (P>0.05). Most shrinkage (94.3%-96.5%) occurred at 30 minutes after mixing for liquid monomer to powder ratio, ranging from 1.0:3.0 to 1.0:1.0. The highest polymerization shrinkage-strain values were observed for the liquid monomer to powder ratio of 1.0:3.0. At 120 minutes after mixing, the shrinkage-strain values were 4.67%, 4.18%, and 3.07% for Jet, Alike, and Snap, respectively. As the liquid monomer to powder ratio increased, the shrinkage-strain values tend to be decreased linearly (r=-0.769 for Alike, -0.717 for Jet, -0.435 for Snap, $r^2=0.592$ for Alike, 0.515 for Jet, 0.189 for Snap; P<0.05). Conclusion. The increase of the liquid monomer to powder ratio from 1.0:3.0 to 1.0:1.0 had a significant effect on the shrinkage-strain kinetics of polymer-based crown and FPD materials investigated. This increased the working time and decreased the shrinkage-strain during polymerization.

Perceived Social Support as a Predictor on Adaptation of Family Who has a Child with Pediatric Cancer (소아암 환아 가족이 인지한 사회적 지지가 적응에 미치는 영향)

  • Tak Young-Ran;Yun E-Hwa;Chon Young-Shin;An Ji-Yeon
    • Child Health Nursing Research
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    • v.9 no.1
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    • pp.9-17
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    • 2003
  • Families of children with cancer face many illness-related demands. The perceived social support is a critical resource for the family adaptation process. And the patterns of family adaptation to childhood cancer varies as characteristics of disease, which is prognosis, the influence of cognition function, and treatment process. The conceptual definition of social support is not unidimensional. However, most studies focus on general aspect of mediating effects on adaptation. Diverse dimensions of perceived social support should be considered in its effectiveness for intervention. Therefore, this study was undertaken to determine whether family's perceived social support influences the family adaptation of family with pediatric cancer and what dimension influences mostly in family adaptation as the characteristics of disease in the family of children with cancer. The subject was consisted of 102 families with pediatric cancer who had been diagnosed as leukemia or brain tumor last 2 years. Those families had participated in the education program or meetings for family who have with pediatric cancer children. The measurement for this study were Personal Resource Questionnaire (PRQ) Part-Ⅱ developed by Brandt and Weinert to measure parents' perceived social support, and the McCubbin's Coping Health Inventory for Parents (CHIP) to measure family coping. The results of this study can be summarized as follows; Regression analysis showed that perceived social support has effect on family adaptation with β=.43, p<.01. In the group of family of child with leukemia, social support as general has effect on adaptation (β=.40, p<.01) and specially, social support perceived as intimacy was strongly effect on family adaptation. And In the group of brain tumor, Social support has effect on adaptation(β=.46, p<.01) and among the social support domains, the self esteem dimension was most predictable to family adaptation. In conclusion, the perceived social support is a predictor on family adaptation and useful vehicle to help family who has child with pediatric cancer. An important clinical implication is that specified support program for intervention may be useful and critical for the family who has diverse pediatric conditions of childhood cancer. Further studies should stress the effects of family support for clinical intervention and is needed with diverse stage of development and pediatric conditions.

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Some Factors Affecting Profitability of Local Public Hospitals (지방의료원의 재무성과 영향요인)

  • Park, Jong-Young
    • Korea Journal of Hospital Management
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    • v.12 no.3
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    • pp.47-67
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    • 2007
  • This paper aims at suggesting several ways lo change financial vulnerability and to improve managerial capability of local public hospitals (LPHs) in Korea through the identification of factors affecting profitability. Several findings of the research are as follows: To begin with, LPHs exhibited a statistically significant difference in their profitability from one another, according to tile analyses of their profitable margins from tile general characteristics. It depends on the number of hospitals in the area, the population of the hospital-built area, the number of competing hospitals, the number of staff per 100 beds, the opening of special clinic, the educational function, and the capacity of rooms. However, there was no variable in the managerial characteristics, presenting a significant difference, in contrast with hospitals which have been managed by private companies and made a great amount of profits. Second, according to the analyses of profit differences in behavioral effort-characteristics, a statistically significant difference was revealed upon the basis of the efforts to improve the clinic service, invite special patients, and shorten the period of being hospitalized. Third, the result of analyses about the difference of profitability from medical care and finance is statistically significant in the rate of labor cost, the rate of management cost, bed-occupancy rate, and the period of being hospitalized. Fourth, according to the analyses of the factors influencing the net profit ratio of the entire capital, Adjusted explanatory power(Adjusted $R^2$) was shown up to 65.2%, which is high. To compare the adjusted explanatory power stage by stage, the first stage model applying only two variables such as structural and strategic characteristics exhibited 23.8%, and the second stage model adding financial characteristics showed 51.5%. The explanatory power was much improved up to 65.2% when the third stage model incorporated the outcome of medical care performance. When the return on investment(ROI) was examined by using the multi-variate linear regression analysis at the final model of third stage, it was found that ROI had a positive relationship with the increase rate of patients, labor costs per doctor, and medical care rate of socially protected inpatients. However, it revealed that ROI had a negative relationship with the ratio of labor costs, the number of patients per managerial staff, and occupancy rate of rooms, respectively. The research suggests that in order for LPHs to increase profitability, LPH, should make efforts not only to attract patients to the hospitals without any discrimination of the patients depending on their financial status, but also to develop efficient management methods to reduce labor costs.

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Subjective Symptoms of Peri-Implantitis and Satisfaction according to Prosthesis Methods (임플란트 보철방식에 따른 임플란트 주위염 자각증상 및 만족도)

  • Cha, Ji-Ae;Han, Gyeong-Soon
    • Journal of dental hygiene science
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    • v.17 no.2
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    • pp.175-182
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    • 2017
  • From March 1, 2016 to August 31, 2016, 375 dental implant patients between the ages of 30 and 70 years to evaluate their subjective symptoms and satisfaction according to prosthesis methods. The collected data were analyzed using the chi-square distribution test, t-test, one-way analysis of variance, and multiple logistic regression. Of the patients with subjective symptoms of peri-implantitis, 40.5% reported food impaction, 49.1% reported bleeding, 61.1% reported pain, 61.9% reported halitosis, and the overall satisfaction level with the implants was 3.95 points. In the prosthesis methods, implant-teeth connective group showed the lowest level of the food impaction (21.3%), the pain (35.5%), and the halitosis (36.6%) (p<0.001), and the lowest bleeding was the implant single (33.8%) (p<0.05). Patient satisfaction was higher in the implant-teeth connective group (4.06 points) and the group without bone grafting (4.03 points) (p<0.01). Factor analysis showed that implant satisfaction was 0.43 times lower in the single implant group and 0.44 times lower in the implant-implant connective group than in the implant-teeth connective group. As a result of the study, it is expected that the method of extending the life of adjacent teeth and restoring the function of the tooth defect region is an implant-teeth connection method, so that it can be utilized positively through various clinical studies.

Modeling Temperature-Dependent Development and Hatch of Overwintered Eggs of Pseudococcus comstodki (Homoptera:Pseudococcidae) (가루깍지벌레(Pseudococcus comstocki (Kuwana))월동알의 온도발육 및 부화시기예찰모형)

  • Jeon, Heung-Yong;Kim, Dong-Soon;Yiem, Myoung-Soon;Lee, Joon-Ho
    • Korean journal of applied entomology
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    • v.35 no.2
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    • pp.119-125
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    • 1996
  • Temperature-dependent development study for overwintered eggs of Pseudococcus comstocki (Kuwana) wasconducted to develop a forecasting model for egg hatch date. Hatch times of overwintered eggs were comparedat five constant temperatures (10, 15, 20, 25, 27$^{\circ}$C) and different collection dates. A nonlinear, four-parameterdevelopmental model with high temperature inhibition accurately described (R2=0.9948) mean developmentalrates of all temperatures. Variation in developmental times was modeled(~~=0.972w9)it h a cumulative Weibullfunction. Least-squares linear regression (rate=O.O06358[Temp.]-0.07566)d escribed development in the linearregion (15-25$^{\circ}$C) of the development curve. The low development threshold temperature was estimated 11.9"Cand 154.14 degree-days were required for complete development. The linear degree-day model (thermal summation)and rate summation model (Wagner et al. 1985) were validated using field phenology data. In degreedaymodels, mean-minus-base method, sine wave method, and rectangle method were used in estimation of dailythermal units. Mean-minus-base method was 18 to 28d late, sine wave method was 11 to 14d late, rectanglemethod was 3 to 5d late, and rate summation model was 2 to 3d late in predicting 50% hatch of overwinteredeggs. hatch of overwintered eggs.

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