• Title/Summary/Keyword: growth modeling

Search Result 876, Processing Time 0.03 seconds

An Analysis of the Effects of Consumer Characteristics and Consumer Trust on Purchase Intention of Environment-friendly Agricultural Products (소비자 특성과 소비자 신뢰가 친환경농산물의 구매의도에 미치는 영향 분석)

  • Kim, Mi-Song;Choi, Hyung-Kyu;Kim, Dong-Hwan
    • Journal of Distribution Science
    • /
    • v.11 no.1
    • /
    • pp.45-53
    • /
    • 2013
  • Purpose - The environment-friendly agricultural product market in Korea sees continual high growth. Recently, the Korean government has been actively fostering environment-friendly agriculture as an engine of future growth. Korean people have increasingly become more health-conscious and interested in food safety issues. Many distribution and retailing companies have responded with various promotional activities. However, most of these are not strategic and appear to have unsatisfactory outcomes. The main purpose of this paper is to suggest effective marketing strategies for environment-friendly agricultural products. To achieve this aim, the study empirically investigates the effects of consumer characteristics and trust on the purchase intention of environment-friendly agricultural products. Research design, data, methodology - Based on the theory of planned behavior, and previous studies related to the purchase intention and consumption of environment-friendly agricultural products, we set up five study hypotheses. These related to the demographic characteristics of consumers, purchase intention, and behavior of the products. We then set up a study model and four study hypotheses relating to health consciousness, environmental consciousness, consumer trust level, purchase intention, and behavior of the products. The data were collected using a questionnaire given to consumers living in Seoul and southern Geonggi Province. The final sample size is 403 and mean age is 44.3. SPSS 15.0 for Windows and Amos 7.0 were used as statistical analysis tools. Meaningful results were derived using frequency analysis, correlation analysis, a t-test, and structural equation modeling. Results - Empirical results of this research are as follows. (1) First, it is shown that consumers consider such attributes as intimacy and health to be important when they buy environment-friendly agricultural products. (2) We also found that consumers recognize the value of environment-friendly agricultural products as high, but their trust level as low. (3) Consumer groups consisting of married couples, with higher education, higher income, and higher age are shown to have a higher intention of buying environment-friendly agricultural products than any other consumer group. (4) It is estimated that the level of consumer trust positively affects the purchase intention of environment-friendly agricultural products. The path coefficient (.138) between consumer trust and purchase intention is statistically significant at the α = .05 level. (5). It is also estimated that environmental consciousness positively affects purchase intention. The path coefficient (.245) between environmental consciousness and purchase intention is statistically significant at the α = 0.05 level. The standardized path coefficients of consumer trust and environmental consciousness with purchase intention are .556 and .288 respectively. Therefore, consumer trust affects purchase intention more than environmental consciousness. (6) Finally, purchase intention is estimated to positively affect purchase behavior. Conclusions - Based upon empirical results, this research suggests that marketers of environment-friendly agricultural products should focus more on increasing consumer trust levels, emphasizing the training and education of employees. The government also should pay attention to a standardized certification system for environment-friendly agricultural products. Marketers of environment-friendly agricultural products should consider the consumer groups of married couples, with higher education, higher income, and higher age as a major target segment.

  • PDF

Biosorption of Pb and Cd by Indigenous Bacteria Isolated from Soil Contaminated with Oil and Heavy Metals (유류와 중금속으로 오염된 토양에서 분리한 미생물의 Pb와 Cd 생물흡착 특성)

  • Kim, Sang-Ho;Chon, Hyo-Taek;Lee, Jong-Un
    • Economic and Environmental Geology
    • /
    • v.42 no.5
    • /
    • pp.427-434
    • /
    • 2009
  • Indigenous bacterium which shows a tolerance to high metal toxicity was isolated from soil concomitantly contaminated with oil and heavy metals. The characteristics of the bacterium for Pb and Cd biosorption was investigated under the various experimental conditions such as bacterial growth phase, the initial metal concentration, the input biomass amount, temperature and pH. The Langmuir adsorption isotherm modeling was described to know the capacity and intensity of biosorption. The low initial concentration of heavy metals and high biomass has a maximum heavy metal removal efficiency, but biosorption capacity of Pb and Cd has different values. Biosorption efficiency was highest in the end of the microbial growth stage and under pH 5~9 condition, but was less affected by temperature variation of 25~$35^{\circ}C$. The maximum biosorption capacity for Pb and Cd was 62.11 and 192.31 mg/g, respectively and each $R^2$ was calculated as 0.71 and 0.98 by applying Langmuir isothermal adsorption equation. Biosorption for Cd was considered as monomolecular adsorption to single layer on the surface of cells, whereas biosorption for Pb was considered as accumulation process into the cell by the microbial metabolism and precipitation reaction with anion of bacteria.

Development of a Gridded Simulation Support System for Rice Growth Based on the ORYZA2000 Model (ORYZA2000 모델에 기반한 격자형 벼 생육 모의 지원 시스템 개발)

  • Hyun, Shinwoo;Yoo, Byoung Hyun;Park, Jinyu;Kim, Kwang Soo
    • Korean Journal of Agricultural and Forest Meteorology
    • /
    • v.19 no.4
    • /
    • pp.270-279
    • /
    • 2017
  • Regional assessment of crop productivity using a gridded simulation approach could aid policy making and crop management. Still, little effort has been made to develop the systems that allows gridded simulations of crop growth using ORYZA 2000 model, which has been used for predicting rice yield in Korea. The objectives of this study were to develop a series of data processing modules for creating input data files, running the crop model, and aggregating output files in a region of interest using gridded data files. These modules were implemented using C++ and R to make the best use of the features provided by these programming languages. In a case study, 13000 input files in a plain text format were prepared using daily gridded weather data that had spatial resolution of 1km and 12.5 km for the period of 2001-2010. Using the text files as inputs to ORYZA2000 model, crop yield simulations were performed for each grid cell using a scenario of crop management practices. After output files were created for grid cells that represent a paddy rice field in South Korea, each output file was aggregated into an output file in the netCDF format. It was found that the spatial pattern of crop yield was relatively similar to actual distribution of yields in Korea, although there were biases of crop yield depending on regions. It seemed that those differences resulted from uncertainties incurred in input data, e.g., transplanting date, cultivar in an area, as well as weather data. Our results indicated that a set of tools developed in this study would be useful for gridded simulation of different crop models. In the further study, it would be worthwhile to take into account compatibility to a modeling interface library for integrated simulation of an agricultural ecosystem.

Predictors of self-worth and self-deprecation trajectories among Korean adolescents (우리나라 청소년의 긍정적 자아존중감과 부정적 자아존중감의 변화궤적과 예측요인)

  • Yoo, Changmin
    • Journal of the Korean Society of Child Welfare
    • /
    • no.59
    • /
    • pp.25-58
    • /
    • 2017
  • This study aimed to identify self-worth and self-deprecation trajectories and their associated factors among Korean adolescents. For these purposes, we used latent growth curve modeling involving 2,350 students who participated in the Korea Children and Youth Panel Survey in 2010, 2012, 2014, and 2015. Major findings are as follows: 1) Adolescents' self-worth and self-deprecation increased with time, but the speed gradually changed to a quadratic function model; and 2) the types of predictors affecting self-worth and self-deprecation were different. Specifically, the factors that affected only self-worth were adolescents' relationship with teachers and household income, and the factors that affected only self-deprecation were presence of disease and parental over interference. Factors affecting both self-worth and self-deprecation were child's sex, parental affection, peer trust, and peer alienation. These results suggest that independent intervention is needed for self-worth and self-deprecation. Furthermore, the results can be an important basis for establishing a more focused intervention strategy when intervening in self-worth and self-deprecation in adolescents.

Influence of Protective and Risk Factors on Delinquent Behavior Trajectories (청소년 비행행동의 궤적에 영향을 미치는 보호요인과 위험요인)

  • Lee, Sang-gyun
    • Korean Journal of Social Welfare Studies
    • /
    • no.39
    • /
    • pp.315-342
    • /
    • 2008
  • The aim of this study was to examine growth trajectories of delinquent behaviors during adolescence. In addition, the effects of protective and risk factors that might account for individual difference in the level of delinquent behaviors and in the rate of change were examined. Four waves of data in the Korea Youth Panel Survey(KYPS) were used to analyze the linear growth modeling. The sample consisted of 3346 adolescents who were assessed at 4 measurement waves with approximately 1-year intervals. The results showed significant individual differences in both final level of delinquent behaviors and in the rate of change across 3 measurement occasions. Adolescent gender, family's socioeconomic background predicted the final level and the rate of change of delinquent behaviors. The protective effects of positive parenting and self-control were significantly associated with problem behaviors and the risk effects of the association with deviant peers and negative stigma were significant on the final level of delinquency. Self-control and deviant peer affiliation had differential influences over time significantly. Practice and policy implications as well as further research topic were discussed in the light of searching for important factors in preventing adolescent problem behaviors.

Influential Factors of Social Relation on the Change in the Depression Level of Elderly -Longitudinal Analysis using a Latent Growth Model (노인의 사회적관계 요인이 우울 궤적에 미치는 영향 -잠재성장모형을 이용한 종단연구)

  • Kim, Jin-hun
    • The Journal of the Korea Contents Association
    • /
    • v.19 no.7
    • /
    • pp.138-148
    • /
    • 2019
  • Although social relation factors are confirmed to be closely associated with the depression level of the elderly through the preceding studies, there has been no specific study on subfactors of social relation that influence the trajectory of depression level. Considering such limitation, this study aims to analyze influencing subfactors of social relation on the trajectory of depression of the elderly. The 3rd, 4th, 5th, and 6th-year data of the Korean Longitudinal Survey of Ageing (KLoSA), which were provided by the Korea Employment Information Service (KEIS), were used in this study and 2,484 people aged 65 and over who responded to all the four-session surveys were used as final analysis subjects. In the result of the longitudinal study on depression level of the elderly aged 65 and over, the individual depression level was confirmed become lowered over time, showing a positive change. Also, the conditional model of Latent Growth Modeling (LGM) was applied to identify specific social network factors that influence the longitudinal change of depression level of the elderly. In the result of the analysis, it was found that initial value of depression of the elderly was influenced by whether they have a spouse or not, number of household member, meeting with close people, whether they do economic activity or not, whether they have a religion or not, etc. and the rate of change in depression of the elderly was influenced by number of household member, meeting with close people, expectation about life, etc. Through above results, this study suggests a need for specific programs and supports to continuously lower the depression level of the elderly.

A study on the Typology and Determinants for Changes in the Social Participation of Middle-aged and Older Population (중·고령자 사회참여 변화 유형화와 결정요인에 관한 연구)

  • Lee, Min-Uk;Jeong, Kyu-Hyoung
    • Journal of the Korea Convergence Society
    • /
    • v.10 no.7
    • /
    • pp.243-249
    • /
    • 2019
  • This study is aimed at offering a typology of changes in the social participation of middle-aged and older population and explore determinants for each type of such changes. The data employed for analysis are the 1st survey (2006) through the 6th version (2016) of the Korea Aging Research Panel Survey. Among the respondents of the panel survey, 1,327 males and 1,520 females with a total of 2,847 respondents were analyzed. As a result of applying the growth mixture modelling through the SPS 22.0 and M-plus 8.0 statistical programs, the changes in the social participation of middle-aged and older population have been classified into the 'high-decreasing', 'moderate-increasing' and 'low-stable' trajectory classes. Analysis of the determinants for each class shows that higher the education level, the more likely they are to belong to the high-decreasing and moderate-increasing classes than the low-stable class, and the more the population lives in urban areas, the more likely they are to belong to high-decreasing trajectory class than to low-stable class. Also, it was found that the probability of belonging to moderate-increasing trajectory class was higher than that of the low-stable class when there was no occupation. Through the results of these analyses, the implications of promoting social participation of middle-aged and older population were discussed.

Classification of Agro-Climatic Zones of the State of Mato Grosso in Brazil (브라질 마토그로소 지역의 농업기후지대 구분)

  • Jung, Myung-Pyo;Park, Hye-Jin;Hur, Jina;Shim, Kyo-Moon;Kim, Yongseok;Kang, Kee-Kyung;Ahn, Joong-Bae
    • Korean Journal of Environmental Agriculture
    • /
    • v.38 no.1
    • /
    • pp.34-37
    • /
    • 2019
  • BACKGROUND: A region can be divided into agroclimatic zones based on homogeneity in weather variables that have greatest influence on crop growth and yield. The agro-climatic zone has been used to identify yield variability and limiting factors for crop growth. This study was conducted to classify agro-climatic zones in the state of Mato Grosso in Brazil for predicting crop productivity and assessing crop suitability etc. METHODS AND RESULTS: For agro-climatic zonation, monthly mean temperature, precipitation, and solar radiation data from Global Modeling and Assimilation Office (GMAO) of National Aeronautics and Space Administration (NASA, USA) between 1980 and 2010 were collected. Altitude and vegetation fraction of Brazil from Weather Research and Forecasting (WRF) were also used to classify them. The criteria of agro-climatic classification were temperature in the hottest month ($30^{\circ}C$), annual precipitation (600 mm and 1000 mm), and altitude (200 m and 500 m). The state of Mato Gross in Brazil was divided into 9 agro-climatic zones according to these criteria by using matrix classification method. CONCLUSION: The results could be useful as information for estimating agro-meteorological characteristics and predicting crop development and crop yield in the state of Mato Grosso in Brazil.

A Study of Longitudinal Changes in Mother-Child Interaction and its Effect on Media Device Addiction (모-자녀 상호작용 변화 양상에 따른 자녀의 미디어 기기 중독 차이)

  • Yeon, Eun Mo;Choi, Hyo-Sik
    • Journal of the Korea Academia-Industrial cooperation Society
    • /
    • v.21 no.12
    • /
    • pp.346-353
    • /
    • 2020
  • The purpose of this study was to explore types of longitudinal changes in interactions between mothers and 4-year-old children in primary school as well as the effects on media device addiction. To explore interaction types between mothers and children, latent class growth modeling (LCGM) and BCH were used in a three-step approach. Data from the 6-10th wave of the Panel Study of Korea Children were used. First, the trajectory of the mother-child interactions was linear and decreased across time. This linear decrease was classified into the following three trajectories: high-decreasing, average-deceasing, and low-decreasing. Second, BCH was performed to examine media device addiction in each trajectory, and the findings show that children who had low initial mother-child interactions over time were more likely to experience daily disturbances in adaptive functions such as withdraw or tolerance than other groups of children. The results indicate that maximizing the quality of mother-child interactions in childhood through primary school can lower media device addiction in children.

The Moderating Effect of Gender in the Relationship between Physical Education and Adolescents' Internalizing and Externalizing Problem Behaviors: Using Multi-level Growth Modeling (체육시간과 청소년의 외현화·내재화 문제와의 관계에서 성별의 조절효과: 다층성장모형의 적용)

  • Taekho Lee;Seokyoung Lee;Yoonsun Han
    • Korean Journal of Culture and Social Issue
    • /
    • v.21 no.2
    • /
    • pp.131-158
    • /
    • 2015
  • This study examined the relationship between physical education and externalizing(aggression) and internalizing(depression, social withdrawal) problem behaviors among adolescents. The moderating role of gender and time in the association between physical education and problem behavior was also identified. This study used data from the second, third, and fourth waves of the middle school student cohort (N=2,133, N=2,151, N=1,979) of the Korean Children-Youth Panel Survey(KCYPS). Main analyses involved multilevel growth model with interaction terms. The dependent variables were aggression, depression, and social withdrawal. The independent variables were gender and physical education (exercise hours) at school. The control variables were abuse, school-adjustment, annual household income and parents' highest level of education. The major longitudinal findings of this study are as follows: First, there was significant change according to the passage of time only in aggression among externalizing and internalizing problems. Second, gender differences exist in aggression and depression. Third, exercise hours of physical education had a negative relationship with internalizing problems. Fourth, there were no gender differences over time in both externalizing and internalizing problems. Fifth, the interaction between exercise hours of physical education and time was statistically significant for social withdrawal. Sixth, the interaction between exercise hours of physical education and gender was statistically significant for depression. The results of this study may become an academic basis for suggesting policy directions that promote increased exercise hours in physical education classes at school.

  • PDF