• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2004년도 추계학술대회 논문집 Vol.17
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• pp.628-631
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• 2004

A tetrafluoromethane$(CF_4)$ is most useful gas in plasma dry etching, because it has a electron attachment cross-section. therefor it is important to calculate transport coefficients like electron drift velocity, ionization coefficient, attachment coefficient, effective ionization coefficient. and critical E/N. The aim of this study is to get these transport coefficients for information of the insulation strength and efficiency of etching process. Electron transport coefficients in $CF_4+Ar$ gas mixture are simulated in range of E/N values from 1 to 250 [Td] at 300[K} and 1 [Torr] by using Boltzmann equation method. The results of this method can be important data to present characteristic of gas for plasma etching and insulation, specially critical E/N is a data to evaluate insulation strength of a gas. and is presented in this paper for various mixture ratios of $CF_4+Ar$ gas mixture.

• 전기학회논문지P
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• 제58권1호
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• pp.44-47
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• 2009

This paper describes the information for quantitative simulation of weakly ionized plasma. We must grasp the meaning of the plasma state condition to utilize engineering application and to understand materials of plasma state. $SF_6$ gas is widely used in industrial of insulation field. In this paper, $N_2$ is mixed to improve pure $SF_6$ gas characteristics. Electron transport coefficients in $SF_6-N_2$ mixture gases are simulated in range of E/N values from 70 to 400 [Td] at 300K and 1 Torr by using Boltzmann equation method. The results of this method. which are ionization coefficient, attachment coefficient, effective ionization coefficient, and critical E/N, can be important data to present characteristic of gas for insulation. Specially critical E/N is a data to evaluate insulation strength of a gas and is presented in this paper for various mixture ratios of $SF_6-N_2$ mixture gases.

• 한국전기전자재료학회논문지
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• 제18권4호
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• pp.375-380
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• 2005

CF₄ molecular gas is used in most of semiconductor manufacture processing and SF/sub 6/ molecular gas is widely used in industrial of insulation field. but both of gases have defect in global warming. C₃F/sub 8/ gas has large attachment cross-section more than these gases, moreover GWP, life-time and price of C₃F/sub 8/ gas is lower than them, therefor it is important to calculate transport coefficients of C₃F/sub 8/ gas like electron drift velocity, ionization coefficient, attachment coefficient, effective ionization coefficient and critical E/N. The aim of this study is to get these transport coefficients for imformation of the insulation strength and efficiency of etching process. In this paper, we calculated the electron drift velocity (W) in pure C₃F/sub 8/ molecular gas over the range of E/N=0.1∼250 Td at the temperature was 300 K and gas pressure was 1 Torr by the Boltzmann equation method. The results of this paper can be important data to present characteristic of gas for plasma etching and insulation, specially critical E/N is a data to evaluate insulation strength of a gas.

• 한국전기전자재료학회논문지
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• 제14권9호
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• pp.773-778
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• 2001

In this dissertation the results of the combined experimental and theoretical studies designed to understand and predict the spatial growth and transport coefficients for electrons in SF$_{6}$ and SF$_{6}$-Ar mixtures have described. The ionization and attachment coefficients in pure SF$_{6}$ and SF$_{6}$-Ar mixtures have been calculated over the range of 10$_{6}$ molecule and for Ar atom proposed by other authors. The transport coefficients for electrons in (0.2%)SF$_{6}$-Ar and (0.5%)SF$_{6}$-Ar mixtures were measured by time-of-flight method, and the electron energy distribution function and the parameters of the velocity and the diffusion were determined by the variation of the collision cross-sections with energy. The results obtained in this work will provide valuable information on the fundamental haviors of electrons in weakly ionized gases and the role of electron attachment in the choice of better gases and unitary gas dielectrics or electro negative components in dielectric gas mixtures. gas mixtures.

• Environmental Engineering Research
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• 제13권3호
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• pp.141-146
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• 2008

Transport of Escherichia coli ATCC 11105 through porous media was investigated in this study using two sets of column experiments to quantify the attachment-related parameters (sticking efficiency, attachment rate coefficient and filter factor). The first set of experiments was performed in quartz sand under different ionic strength conditions (1, 20, 100, 200 mM) while the second experiments were carried out in quartz sand mixed with metal oxyhydroxide-coated sand (0, 5, 10, 25%). The breakthrough curves of bacteria were obtained by monitoring effluent, and then bacterial mass recovery and attachment-related parameters were quantified from these curves. The first experiments showed that the mass recoveries were in the range of 13.3 to 64.7%, decreasing with increasing ionic strength. In the second experiments, the mass recoveries were in the range of 15.0 to 43.4%, decreasing with increasing coated sand content. The analysis indicated that the sticking efficiency, attachment rate coefficient and filter factor increased with increasing ionic strength and coated sand content. The value of filter factor in the first experiments ranged from 1.45 e-2 to 6.72 e-2 1/cm while in the second experiments it ranged from 2.78 e-2 to 6.32 e-2 1/cm. Our filter factor values are one order of magnitude lower than those from other studies. This discrepancy can be attributed to the size of sand used in the experiment. The analysis demonstrated that the travel distance of bacteria estimated using the filter factor can be varied greatly depending on the solution chemistry and charge heterogeneity of porous media.

• 부모자녀건강학회지
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• 제7권1호
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• pp.38-49
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• 2004

This study is to investigate the main factors influencing prenatal attachment. The research method is on the basis of descriptive correlational study, and data collecting period was from 11 to 29, November, 2003. The objects of this study were 100 pregnant women of two OBGY Hospitals in Masan. Using the SPSS/WIN 10.1 program the data were analyzed by t-test, ANOVA, Pearson correlation coefficient, stepwise multiple regression analysis. The result of this study was as follows : The mean score of prenatal attachment was 2.64, the mean score of physical discomforts, 1.61, the mean score of husband-wife attachment, 3.28, the mean score of psychosocial adjustment of pregnancy, 1.82. The degree of prenatal attachment according to general characteristics was significantly difference according to religion. The degree of prenatal attachment according to obstetrical characteristics was significantly difference according to Lamaze class, Taekyo. Significant correlations of prenatal attachment was found in both psychosocial adjustment of pregnancy, Taekyo, husband-wife attachment, Lamaze class, religion. Stepwise multiple regression analysis showed that 52% of the variance in prenatal attachment was significantly accounted by psychosocial adjustment of pregnancy(34%), Taekyo(6%), husband-wife attachment(5%), Lamaze c1ass(5%), and religion(3%). Further findings of this study support the development of creative strategies to enhance positive attachment relationship for pregnant woman.

• 수산해양교육연구
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• 제24권6호
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• pp.793-805
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• 2012

This study investigated the influence of mother and peer attachment on conflict resolution strategies of children. Following research questions were established. First, what is the influence of mother and peer attachment on conflict resolution strategies of children? Second, does the influence of mother and peer attachment on conflict resolution strategies of children differ according to sex? Third, what is the relative influence of mother and peer attachment on conflict resolution strategies of children? 485 fifth graders(male, 184; female, 163) from elementary schools located in Busan participated in this study and completed Inventory of Parent and Peer Attachment and Conflict Resolution Strategies Scale. Collected data were analyzed using t-test, Pearson Correlation Coefficient, Simple Regression and Multiple Regression Analysis. Major findings of this study were summarized as follows: First, both mother and peer attachment influenced on compromising and integration, avoiding and obliging strategies although the degree of influence were different. Second, the influence of mother and peer attachment on conflict resolution strategies differ according to gender. Third, the influence of peer attachment on conflict resolution strategies were greater than the one of mother attachment. Finally the significance of this study were presented with comments on limitations of this study.

• 동서간호학연구지
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• 제17권2호
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• pp.132-138
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• 2011

Purpose: The purpose of this study was to explore the relationship among suicidal ideation, parental attachment, and self-identity of college students. Methods: This study was designed as a descriptive correlational research. The participants were 314 college students in Gyeongbuk province. Data were collected from September 23 to Oct 5 in 2009 using a structured questionnaire. Data were analyzed by t-test, ANOVA, and Pearson correlation coefficient using SPSS WIN (Version 12.0). Results: Suicidal ideation showed negative correlations with maternal and paternal attachment (r=-.20, p<.001; r=-.24, p<.001, respectively) as well as self-identity (r=-.37, p<.001). Self-identity had positive correlations with maternal and attachment (r=.16, p=.006; r=.23, p<.001, respectively). Conclusion: The findings suggest that suicidal ideation may be decreased when college students have higher parental attachment and self-identity. Strategies to improve parental attachment and self-identity are needed in near future.

• 한국환경생태학회지
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• 제26권2호
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• pp.283-291
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• 2012

본 논문은 경주국립공원 내 사찰숲길 이용자의 장소애착이 환경요인에 대한 인식과는 어떠한 구조적 관계를 형성하고 있는 지를 구조방정식모형을 활용하여 탐색하며, 국립공원 관리에 있어서 경관선호 보다는 경관애착에 근거한 보전적 측면에서의 정책적 함의를 제공하는데 있다. 경주국립공원 내 대표적인 사찰인 불국사를 찾는 탐방객을 대상으로 설문조사를 실시한 후, 수집된 자료를 분석하여 구조방정식모형을 도출하였다. 연구 결과, 장소의존성은 장소애착에 대하여 유의하게 긍정적으로 영향을 미치는 것으로 나타난 반면, 장소정체성은 장소애착에 대하여 통계적으로 유의한 영향을 나타내지는 않는 것으로 나타났다. 장소의존성이 보다 장소애착에 영향을 미치는 것으로 나타났다(경로계수=0.55). 장소애착은 환경요인의 중요성에 대한 인식에 있어서 경관이용과 시설이용 모두 유의하게 정(+)의 방향으로 영향을 미치는 것으로 나타났다. 장소애착은 사찰숲길 이용의 중요성에 있어서 시설요인 보다는 경관요인에 대하여 보다 강한 영향력을 보이는 것으로 나타났다(경로계수=1.01). 이러한 결과는 국립공원의 경관자원의 중요성을 다시 확인시키며, 이로부터 사찰숲길 경관의 보전에 중점을 둔 관리방안이 마련되어야 할 것으로 판단된다.

• 한국학교ㆍ지역보건교육학회지
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• 제13권1호
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• pp.33-43
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• 2012

Objectives: The study has a purpose of contributing to understanding children of multi-cultural families and healthy development of children by examining influences of parental attachment perceived by the children on their anger trait and anger expressions. Methods: The data were collected from 113 students in grade 4~6, and analyzed using descriptive statistics, t-test, pearson correlation coefficient by the SPSS/PC 18.0 program. Results: The result showed the stable attachment with parents significantly influences children's anger and expression(anger out/control). And mother's attachment was significantly stronger than father's attachment, especially mutual trust and communication. Father's attachment had significantly negative influences state-trait anger and anger out/in, and mother's attachment had significantly negative influences state-trait anger and anger out. Actually father's attachment had stronger influences children's anger and anger expression. Conclusions: There was relationship between father's attachment and anger trait/ expression by children of multi-cultural families. For the effective management of multi-cultural children's anger, programs focusing on improving father-child relationships need to be established.