• 한국환경복원기술학회지
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• 제7권2호
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• pp.46-51
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• 2004

In this paper, reinforcement of soil shear strength by bamboo(substitute materials simulating a root system) are evaluated by soil strength parameters(apparent cohesion(c) and internal friction angle(tan${\Phi}$)), using simple shear tester which clearly depicts shear deformation and controls soil suction. The results show that the internal friction angle does not change under various soil suction conditions but the apparent cohesion, which reach a peak in suction of 45cm$H_2O$ near critical capillary head, is effected by soil suction. And the reinforcement of soil strength by bamboo are expressed by apparent cohesion more than internal friction angle. In addition the increment of apparent cohesion by bamboo reached a peak in suction 45cm$H_2O$ too.

• 한국농공학회지
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• 제23권3호
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• pp.96-104
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• 1981

In order to investigate the characteristics of the shear strength of the unsaturated cohesive soils which has mean characters of sand and clay widely used for banking, I selected soil samples from An-sung district and, against it, performed direct shear test and unconfined compression test changing grain size, compaction energy and moisture content and also performed triaxial compression test under optimum moisture content. The results are as follows; 1.As the passing percent of the No. 200 sieve increased from 23.6% to 56.1%, cohesion increased from 0. 202kg/cm2 to 0. 398kg/cm2 under the direct shear test and from 0.38 kg/cm2 to 1. 05kg/cm2 under the tria4al compression test, internal friction angle decreased from 44. 78$^{\circ}$ to 34. 34$^{\circ}$ under the direct shear test and from 31. 88$^{\circ}$ to 13. 31$^{\circ}$ under the triaxial compression test. 2.Cohesion showed it's maximum value around OMC and internal friction angle showed a tendency to increase according to the decrease of water content but it's increasing ratio was relatively slow. 3.Decreasing ratio of cohesion and internal friction angle was relatively sensitive according to the decrease of compaction energy. 4.The smaller of the vertical stress and the coarser of the grain size of samples, changing of the volume showed a tendency to increase and as the increase of water content, the shear displacement (dh) at failure shear stress ($\tau$f) showed maximum and the $\tau$f-dh curve was gentle. 5.To synthesize the results of the direct shear test and the triaxial compression test, cohesion showed higher under the triaxial compression test and internal friction angle showed a tendeney to appear higher under the direct shear test. It seems that we can get correspondent results by removing the side friction of mold with soils and adjusting the vertical stress and shearing speed under the direct shear test.

• 한국터널지하공간학회 논문집
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• 제12권2호
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• pp.117-127
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• 2010

대부분의 지하구조물들은 불포화 지반에 건설되어있는 경우가 많으므로, 본 논문에서는 불포화토의 겉보기 점착력이 지반 굴착시 거동에 미치는 영향에 관하여 연구하였다. 이를 위해 압력판 추출시험, 불포화 삼축압축시험, Trap-door 시험을 수행하여 다양한 범위의 겉보기 점착력에서 지반의 거동이 어떻게 변화하는지 관찰하였다. 그 결과 완전 포화와 완전 건조 상태일 때는 지반이 거의 같은 거동을 보이고, 불포화 상태일 때는 함수비의 증가에 따라 그 거동이 매우 달라짐을 알 수 있었다. 이를 통해 겉보기 점착력이 지하 구조물 굴착 시 매우 중요한 역할을 한다는 것을 알 수 있었다.

• 가정과삶의질연구
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• 제19권6호
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• pp.185-196
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• 2001

The purpose of this study was to examine the relationships among the internal locus of control, perceived family support, family cohesion, family adaptability, and children's social behaviors. The subjects were 285 6th and 8th grade students and their homeroom teachers. A questionnaire was used as survey method. Data were analyzed by Pearson's correlation, t-test, ANOVA, Duncan post test. and multiple regression. The results are as follows: First, internal locus of control was positively related to social competence and negatively related to antisocial behavior. Perceived family support, family cohesion and adaptability were positively related to social competence and negatively related to antisocial behavior. Second, girls were higher internal locus of control, family cohesion, family adaptability and social competence and lower in antisocial behavior than boys. The 8th graders had lower scores than 6th graders in perceived family support, family cohesion, family adaptability and social competence and higher level of antisocial behavior. Third, perceived family support and family adaptability impacted social competence in girls, and grade impacted social competence in boys. Grade, perceived family support and locus of control had significant effects on the antisocial behavior in boys, and perceived family support impacted antisocial behavior in girls.

• Geomechanics and Engineering
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• 제11권6호
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• pp.879-896
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• 2016

A new earth pressure equation considering the arching effect in $c-{\phi}$ soils was proposed for the accurate calculation of earth pressure on circular vertical shafts. The arching effect and the subsequent load recovery phenomenon occurring due to multi-step excavation were quantitatively investigated through laboratory tests. The new earth pressure equation was verified by comparing the test results with the earth pressures predicted by new equation in various soil conditions. Resulting from testing by using multi-step excavation, the arching effect and load recovery were clearly observed. The test results in $c-{\phi}$ soil showed that even a small amount of cohesion can cause the earth pressure to decrease significantly. Therefore, predicting earth pressure without considering such cohesion can lead to overestimation of earth pressure. The test results in various ground conditions demonstrated that the newly proposed equation, which enables consideration of cohesion as appropriate, is the most reliable equation for predicting earth pressure in both ${\phi}$ soil and $c-{\phi}$ soil. The comparison of the theoretical equations with the field data measured on a real construction site also highlighted the best-fitness of the theoretical equation in predicting earth pressure.

• 대한가정학회지
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• 제33권1호
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• pp.83-98
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• 1995

The purpose of this study was to identify the influence of adolescent-percived family cohesion on adolescent adjustment. The 443 subjects were selected were selected randomly from the second grade of middle and high schools in the city of Taegu. The instruments of measurement were FACES lll, State-Trait Anxiety Inventory, Depression Scale, and Self-Esteem Scale. Factor analysis, Cronbach's α, MANOVA, and Scheffe test were conducted for the data analysis. The major findings of this study were as follows: The degree fo adolescent adjustment could be different according to the level of family cohesion. Especially, adolescents who perceived their families as high in cohesion felt anxiety and depression less, and had high selt-esteem in comparison with other levels of cohesion.

• 아동학회지
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• 제13권1호
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• pp.112-124
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• 1992

The purpose of this study was to identify the relation between juvenile deliquency and parent-adolescent communication, the family cohesion and adaptability as variables of psychological environment of the family. The subjects were 143 juvenile deliquents in jail, aged 16 to 19, and 347 9th, 10th, 11th, 12th grade students who resided in low income areas in Seoul and Taegu. The research data were collected by structured questionnaire. 143 juvenile delinquents and 87 students whose degree of deliquency was more than M+(0.5*S.D) were selected as the final data source. The statistical methods were frequency percentile, pearson's correlation, one-way ANOVA. Scheffe'test and multiple regression analysis. The major findings showed that (1) juvenile deliquency was significantly related to father-closed communication type. (2) juvenile deliquency was significantly related to low family cohesion and adaptability, (3) the family cohesion and adaptability was positively correlated with parent-adolescent communication. Father-adolescent communication had more important effect upon the family cohesion and adaptability than mother-adolescent communication.

• Human Ecology Research
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• 제54권4호
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• pp.441-450
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• 2016

This study examined how parental role stress, family cohesion, and family adaptation of mothers who have adolescent children influenced parental efficacy. The subjects were 739 mothers of 370 junior high school and 369 senior high school children. Collected data were analyzed using t-test, correlation analysis, and hierarchical regression analysis after analyzing the data. The results of the study were as follows. First, mothers with high incomes, high educational level, and children with high school grades saw an increase in parental efficacy. Second, there were significant positive correlations in parental role stress, family cohesion, family adaptation and the parental efficacy of mothers. Third, the results of this study showed that parental role stress, family cohesion, and family adaptation were factors to understand the parental efficacy of mothers. Family cohesion was also an important factor to understand the parental efficacy of mothers. The findings confirm that the anxiety of parental role stress for mothers who have adolescent children is not a negative factor in regards to lower parental efficacy. The findings suggest that parental education programs for mothers of adolescent children and a required social welfare system for parental roles was not recognized as a stress factor.

• 한국생활과학회지
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• 제23권6호
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• pp.1071-1087
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• 2014

The purpose of this study was to examine children's self-regulation and their problem behavior according to family interaction types. The subjects were 227 children and their mothers, and 14 teachers in Jeonbuk. To obtain family interaction types, self-questionnaires of FACES III are given to mothers. Also, self-questionnaires of children's self-regulation and problem behavior were given to teachers. The data were analyzed by computing t-test, ANOVA, Duncan post test, and multiple liner regression. The results were as follows. First, There was a difference in the children's self regulation and problem behavior, but not in family cohesion and adaptability, according to the children's sex, age, and family variables. Second, it was found that there was a difference in self-regulation and problem behavior according to family interaction types. It showed that self-regulation was higher and problem behavior was lower in the most 'enmeshed' families in cohesion and the most 'chaotic' families in adaptability. Third, considering the relative strength of each variable on children's problem behavior, it was shown that children's sex and age had the greatest influence on problem behavior, followed by self-regulation and family's cohesion. In conclusion, it is suggested that the efforts to improve family cohesion as a psychological environment should be made in order to increase the children's self regulation and to decrease the children's problem behavior.

• 한국농촌생활과학회지
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• 제4권2호
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• pp.99-114
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• 1993

This study is conducted to find out what differences are made on among home-environmental variables, family cohesion, adaption and communication, and to define what variables influence to communication satisfaction of adolescent children. Questionaire survey method was used. The subjects of this study were 578 male and female middle school students living in Kwangiu from July 6, 1992 to July 15, 1992. For the statistical analysis of data, frequency distribution, percentage, average, standard deviation, T-test, F-test, Pearson's correlation and regression analysis were performed. The main findings were as follows : 1) Family cohesion and adaptability variables showed significant difference according to adolescent's sea age, father's education level, income level, occupation and father's religion. 2) Communication showed significant difference according to adolescent's sex, age, father's age, education level, income level, occupation and father's religion. 3) Communication satisfaction showed significant difference about adolescent's age, father's income level. 4) Communication satisfaction showed significant difference by high level in reference to family cohesion and adaptability. 5) Communication satisfaction in reference to communication showed significant difference. 6) The most influential variable on communication satisfaction between fathers and their adolescents children was active response and marked positive influence in order family adaptability, friendly nonverbalism.