• Korean Journal of Social Welfare
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• v.62 no.4
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• pp.171-192
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• 2010

The purpose of this study is to examine factors on wage of the Disabled. This study attempts to identify organizational effects on wage of the disabled. Then, this study adopts hierarchical linear model for the study purpose. Data used for this article is the survey on the vocational rehabilitation facilities in Seoul. The results are as follows. First, wage of the disabled is different from organizations as well as individuals. So, there are necessities in the consideration of organizational effects and the application of hierarchical linear model. Second, effects on wage of the disabilities controlling individual factors such as age, educational level, period using the facilities, sex, whether or not beneficiary, type of disability are different from organization. Finally, there are interaction effects of type of disability and organizational character variables. The implications of these findings are as follows. First, more political concerns should be given on the management of vocational rehabilitation facilities. Second, it is needed to concern about vocational rehabilitation of the mentally disabled.

• Korean Journal of Child Studies
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• v.30 no.4
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• pp.87-97
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• 2009

This study used Hierarchical Linear Modeling analysis to investigate the effects of individual self-regulated cognitive strategies and public education on middle school students' academic achievement. Participants were 6389 (boys 3287, girls 3102) middle school students from the 2005 data of the Korea Education Longitudinal Study. Results were as follows : (1) there were significant differences among different schools in middle school students' academic achievement, i.e. 20% of variance in English achievement and 15% of variance in mathematics achievement were explained by school differences. (2) Students' elaboration and meta-cognitive strategy influenced academic achievement positively. (3) Predictor variables by ability grouping, supplementary class, and/or self-learning class had no significant effects on students' academic achievement.

• International Journal of Automotive Technology
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• v.7 no.6
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• pp.749-756
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• 2006

This paper presents a complex stochastic wheelbase preview control method of a motorcycle suspension based on hierarchical modeling method. As usual, a vehicle suspension system is controlled as a whole body. In this method, a motorcycle suspension with five Degrees of Freedom(DOF) is dealt with two local independent 2-DOF suspensions according to the hierarchical modeling method. The central dynamic equations that harmonize local relations are deduced. The vertical and pitch accelerations of the suspension center are treated as center control objects, and two local semi-active control forces can be obtained. In example, a real time Linear Quadratic Gaussian(LQG) algorithm is adopted for the front suspension and the combination of the wheelbase preview and LQG control method is designed for the rear suspension. The results of simulation show that the control strategy has less calculating time and is convenient to adopt different control strategies for front and rear suspensions. The method proposed in this paper provides a new way for the vibration control of multi-wheel vehicles.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.21 no.6
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• pp.933-941
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• 1997

In the analysis of thin elastic structures such as plate and shell-like structures, classical lower-order theories like Kirchhoff and Reissner-Mindin theories are insufficient to describe the behavior of such structures in the region where the state of stresses is complex. On the other hand, the fully three dimensional theory of linear elasticity can provide desired analysis accuracy, but requires expensive computational implementation compared to the classical theories. This paper is concerned with the development of hierarchical models for elastic structures which can be used for hierarchical modeling for the analysis of such structures. Derivation and limit model analysis (when the thickness of structures tends to zero) of hierarchical models are presented together with a introduction of modeling error estimation. Also, numerical results supporting theoretical results are given.

• Korean Journal of Childcare and Education
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• v.14 no.3
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• pp.97-115
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• 2018

Objective: This study aimed to analyse the influence of young children's playfulness at home and class characteristics on their playfulness at kindergarten. Methods: Twenty eight classes of 3, 4 and 5 year olds in Gyeonggi and Chungbuk provinces were recruited. Participants of this study were mothers and head teachers of the children of recruited classes. Analyses was implemented using hierarchical linear modeling with HLM 7.0. Results: Differences were found in children's playfulness at kindergarten according to their classes. Individual characteristics including, gender, age and playfulness at home were shown to have significant influences on playfulness at kindergarten, while relevance of variable class characteristics to playfulness at kindergarten was not observed. Conclusion/Implications: It is concluded that playfulness of children is more related to playfulness at home rather than class characteristics, implying the strong characteristic of playfulness as an individual trait.

• Korean Journal of Childcare and Education
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• v.11 no.2
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• pp.59-85
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• 2015

The purpose of this study was to investigate the effects of child care teachers' emotional supports in individual classrooms on children's social skills, including self-control, assertion, cooperation, and responsibility that were related to their character development. Data were collected in a purposive sample involving 32 teachers working with 646 children at age five and 555 parents of the children. Hierarchical Linear Modeling (HLM) was used to analyze a two-level model. The results showed that there were significant differences among classes with data reported by teachers but characteristics such as teachers' education and work experiences, child-teacher ratio, and type of child care centers as well as teacher's emotional supports did not explain the differences. Children's age and gender, which were predictors at the individual level, significantly explained their level of social skills reported by parents as well as teachers. The findings implied that other predictors influencing differences among classes should be explored in future studies.

• Korean Journal of Social Welfare
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• v.66 no.4
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• pp.77-100
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• 2014

To validate the effects of students' individual factor, school organizational factor, and teacher factor on violent behavior toward peers in school, this study applied Hierarchical Linear Modeling and analyzed it using the HLM 7 program. To this end, it used survey data of students from 50 middle schools in Seoul and Gyeonggi province. A total of 1,777 cases from 50 middle schools were used for individual student-level analysis (Level 1), and used for school-level analysis (Level-2). According to the results of the analysis, student-level variables such as attitude toward violence, experience of child abuse at home, and delinquent peers had significant effects on school violence. The effects of violent discipline by teacher, which are used as a school-level variable, was statistically significant. Based on the result of the study, action plans and policies to resolve school violence were discussed.

• Korean Journal of Labor Studies
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• v.19 no.1
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• pp.65-104
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• 2013

This study aims to examine the intermediary roles of employee performance between high performance work system (HPWS) and its operational performance on the resource based view. Taking into account the unit of analysis, this study used a hierarchical linear modeling analysis in order to test rigorously the association between HPWS at the organisational level and employee performance at the individual level. For this empirical test, Human Capital Corporate Panel (HCCP) data including 316 firms and 7,872 respondents (including 923 team leaders) were used. To meet the unit of analysis and test the mediation effect, data at the individual and team level were aggregated into the organisational level. The empirical results show that HPWS have a positive impact on operational performance as well as employee performance such as job satisfaction, organisational commitment and organisational trust. Regarding the mediation effect, job satisfaction and organisational trust mediate between HPWS and operational performance. Theoretical implications are discussed in conclusion.

• Coupled systems mechanics
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• v.7 no.5
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• pp.509-524
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• 2018

A hierarchical multi-scale modeling strategy devoted to the study of a Bitumen-Bound Gravel (BBG) is presented in this paper. More precisely, the paper investigates the temperature-dependent linear viscoelastic of the material when submitted to low deformations levels and moderate number of cycles. In such a hierarchical approach, 3D digital Representative Elementary Volumes are built and the outcomes at a scale (here, the sub-mesoscale) are used as input data at the next higher scale (here, the mesoscale). The viscoelastic behavior of the bituminous phases at each scale is taken into account by means of a generalized Maxwell model: the bulk part of the behavior is separated from the deviatoric one and bulk and shear moduli are expanded into Prony series. Furthermore, the viscoelastic phases are considered to be thermorheologically simple: time and temperature are not independent. This behavior is reproduced by the Williams-Landel-Ferry law. By means of the FE simulations of stress relaxation tests, the parameters of the various features of this temperature-dependent viscoelastic behavior are identified.

• Korean Journal of Social Welfare
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• v.58 no.2
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• pp.119-141
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• 2006

This study aims to explore the status and characteristics of the working poor and to identify the major determinants of their statistic status. For this, longitudinal panel data (from 2nd wave(1999) data to 7th wave(2004) data) from Korean Labor and Income Panel Study (KLIPS), is used. The data is analyzed by adopting Hierarchical Generalized Linear Model (HGLM), which is known as an app.opriate data analysis method for the hierarchically structured data, to look at the factors that affect on the poverty status of the working people. The results show that 1) it is estimated that about 1 out of 10 working people (about 10.0%) are poor, and 2) sex, education level, marital status, region where they lives, employment status, occupation type, and industry type that they are working at are significant predictors in determining their poverty status. Unlike the results of the previous studies, however, the number of the household member, age are not influenced on their poverty status. Based on these results, several policy implications are presented at the end of this paper.