• Korea-Australia Rheology Journal
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• 제21권4호
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• pp.245-268
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• 2009

Recent developments in dilute polymer solution rheology are reviewed, and placed within the context of the general goals of predicting the complex flow of complex fluids. In particular, the interplay between the use of polymer kinetic theory and continuum mechanics to advance the microscopic and the macroscopic description, respectively, of dilute polymer solution rheology is delineated. The insight that can be gained into the origins of the high Weissenberg number problem through an analysis of the configurational changes undergone by a single molecule at various locations in the flow domain is discussed in the context of flow around a cylinder confined between flat plates. The significant role played by hydrodynamic interactions as the source of much of the richness of the observed rheological behaviour of dilute polymer solutions is highlighted, and the methods by which this phenomenon can be incorporated into a macroscopic description through the use of closure approximations and multi scale simulations is discussed.

• 아동학회지
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• 제13권2호
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• pp.129-144
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• 1992

The purpose of this study was to investigate the current status of family child care. The status of family child care was explored in terms of general characteristics, program quality, and child behavior. The subjects were 17 family child care and their 102 children and 60 parents. Harms & Clifford's (1989) FDCRS(Family Day Care Rating Scale) was used to measure program quality. Child behavior was recorded by time sampling in two 30 min observations during the free play session in each facility. A questionnaire for caregiver and parents was used to investigate general characteristics. The data were analysed by frequency, percentage, and Pearson's r. Results showed that (1) a wide range of variable accounted for the general characteristics of family child care, (2) the level of program quality as rated by the FDCRS was below mid-point, (3) children engaged in solitary behavior much more than in peer interactions or caregiver-child interactions.

• 아동학회지
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• 제25권5호
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• pp.73-94
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• 2004

The study examined the effects of an intervention program for improving mother-child interaction behaviors of mothers with developmentally delayed young children. The program consisted of three main activities, lectures for good parenting, video-feedback of mother-child interactions, and consultation for problem behaviors of children. The subjects were 4 mothers of 5-6 years old children with developmental delays who were referred to a social competence program of a child counseling center. The mothers were identified to have problematic mother-child interaction behaviors through clinical interviews. The program ran for 16 sessions, one parent group leader implemented each session for 90-120 minutes once a week. The videotaped data of mother-child interactions for 10 minutes every 4 sessions were estimated by Maternal Behavior Rating Scale(MBRS) and qualitatively analyzed by transcription of communications between mothers and their children. It concluded that the intervention program enhanced mother-child interaction behaviors.

• International Journal of Concrete Structures and Materials
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• 제5권1호
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• pp.3-10
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• 2011

Theoretical models for prediction of the mechanical properties of cement mortar are developed based on the morphology and interactions of cement hydration products, capillary pores and microcracks. The models account for intermolecular interactions involving the nano-scale calcium silicate hydrate (C-S-H) constituents of hydration products, and consider the effects of capillary pores as well as the microcracks within the hydrated cement paste and at the interfacial transition zone (ITZ). Cement mortar was modeled as a three-phase material composed of hydrated cement paste, fine aggregates and ITZ. The Hashin's bound model was used to predict the elastic modulus of mortar as a three-phase composite. Theoretical evaluation of fracture toughness indicated that the frictional pullout of fine aggregates makes major contribution to the fracture energy of cement mortar. Linear fracture mechanics principles were used to model the tensile strength of mortar. The predictions of theoretical models compared reasonably with empirical values.

• 가정과삶의질연구
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• 제31권6호
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• pp.97-112
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• 2013

This study was conducted to investigate the effect of sandplay therapy for couples on the self-differentiation, and heterosexual relationship satisfaction, of couples who are college students'. The subjects were four couples who are college students living in Seoul with low self-differentiation and heterosexual relationship satisfaction. I carried out sandplay therapy on four couples for once a week for 10 weeks, and each session was 70 minutes long. In this study, the self-differentiation scale was modified for Korea on the basis of Bowen's family systems theory (1976), and it was used as a research tool. Yu (2000) and Lee (2000) made a scale to measure heterosexual relationship satisfaction after they adjusted the Korea Marital Satisfaction Inventory (K-MSI). The scale was also used in order to compare pre-therapy and post-therapy traits and identify any changes. In addition, the group's behavior and interactions were observed and recorded in each session throughout the process of sandplay therapy with the couples, and the behanior and interactions were analyzed along with the change flow in the sand trays. The study's outcomes are summed up as follows. First, sandplay therapy with couples advances the level of self-differentiation in college students. Second, sandplay therapy with couples improves the heterosexual relationship satisfaction on college students. Third, the trays used in sandplay therapy with couples showed positive changes as the therapy progressed. As the sessions continued, negative factors in the trays decreased and the trays converged into one. As the sessions proceeded, it was observed that the couples became closer, felt more comfortable with each other, compromised and reflected on their relationship. The study's results show that sandplay therapy with couples increased the level of self-differentiation in college students and heterosexual relationship satisfaction, thus proving the therapy's effectiveness.

• 임상간호연구
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• 제14권1호
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• pp.33-44
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• 2008

Purpose: This study was performed to determine the effects of foot reflexology on pain and quality of sleep in patients with terminal cancer. Method: Quai-experimental research design was used. The subjects of this study were consisted of 19 for experimental group and 18 for control group. Visualue Scale(VAS) was used as the measurement tool of pain in this study, Verra & Snyder-Halpern Sleep Scale(VSH) and Visual Analogue Scale(VAS) were used as the measurement tool of perceived quality of sleep. Data were analyzed using statistical methods such as frequency, percent, $x^2$-test, t-test using SPSS WIN 12.0 program. Results: The hypothesis 1 that the experimental group with reflexology has less degree of pain than the control group without reflexology was supported (t=5.41, p<.001). The hypothesis 2 that the experimental group with reflexology has higher degree of VSH Scale than the control group without reflexology was supported(t=2.37, p=.02). The hypothesis 3 that the experimental group with reflexology has the difference among the mean of sleep VAS Scale during the 12 measurement periods was not supported(F=1.63, p=.08), and no significant interactions between group and time. Conclusion: It is considered that reflexology is effective for reducing cancer pain and improving quality of sleep in patients with terminal cancer.

• 아동학회지
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• 제36권5호
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• pp.95-113
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• 2015

This study aimed to develop and validate a scale which could be used to evaluate mathematical interactions of parents with their young children. The subjects comprised 408 mothers of 4-6-year-old children. Means, standard deviation, $x^2$, Cramer's V, exploratory factor analysis, confirmatory factor analysis, Pearson correlations, and Cronbach's ${\alpha}$ were calculated. First, 49 items were developed through a review of relevant research, parent interviews, confirmation of item adequacy and content validity. These items were then edited down to a final list of 24 items representing 4 factors identified by exploratory factor analysis. Second, this 24-item. 4-factor scale was shown to have adequate construct validity, norm validity, and reliability by confirmatory factor analysis, Pearson correlation analysis, Cronbach's ${\alpha}$. In conclusion, the final mathematical interaction scale for young children's parents was composed of 24 items with 4 factors: "interaction regarding numbers and operations, measurements, and patterns", "interaction regarding data collection and result presentation", "interaction with picture books", and "interaction regarding shapes and figures"

• 공학교육연구
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• 제23권5호
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• pp.51-60
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• 2020

The purpose of this study is to develop and validate an Engineering Empathy Instrument. Engineering empathy is defined as the ability that encompasses the following three qualities, a skill to interpret social issues and phenomenon that may occur in the process of interactions between human beings and engineering systems, a practical orientation that enables one to take stakeholders' perspectives to carry out an engineering project, and a professional way of being that acknowledges empathic skills and associated practice orientations. Based on this notion, we develop a scale to measure engineering empathy and have surveyed 429 engineering students. Evidence for the validity and reliability of the scale is presented. In conclusion, we find that engineering empathy can be measured and conceptualized as three domains: a Learnable Skill (ELS), a Practical Orientation (EPO), and a Professional Way (EPW). We also find that sophomores show the highest level of engineering empathy as compared with other graders. While students accumulate technical knowledge, their understanding about engineering in social and interpretational contexts gets weakened. This implies that engineering education necessarily emphasizes the impacts of engineering solutions in interpersonal, societal, technologies, and environmental contexts.

• 대기
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• 제28권2호
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• pp.175-185
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• 2018

Characteristics of precipitation response to enhanced aerosols have been investigated during the severe haze events observed in Korea for 2011 to 2016. All 6-years haze events are classified into long-range transported haze (LH: 31%), urban haze (UH: 28%), and yellow sand (YS: 18%) in order. Long-range transported one is mainly discussed in this study. Interestingly, both LH (68%) and YS (87%) appear to be more frequently accompanied with precipitation than UH (48%). We also found out the different timing of precipitation for LH and YS, respectively. The variations of precipitation frequency for the LH event tend to coincide with aerosol variations specifically in terms of temporal covariation, which is in contrast with YS. Increased aerosol loadings following precipitation for the YS event seems to be primarily controlled by large scale synoptic forcing. Meanwhile, aerosols for the LH event may be closely associated with precipitation longevity through changes in cloud microphysics such that enhanced aerosols can increase smaller cloud droplets and further extend light precipitation at weaker rate. Notably, precipitation persisted longer than operational weather forecast not considering detailed aerosol-cloud interactions, but the timescale was limited within a day. This result demonstrates active interactions between aerosols and meteorology such as probable modifications of cloud microphysics and precipitation, synoptic-induced dust transport, and precipitation-scavenging in Korea. Understanding of aerosol potential effect on precipitation will contribute to improving the performance of numerical weather model especially in terms of precipitation timing and location.

• 광물과 암석
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• 제33권4호
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• pp.463-475
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• 2020

최근 토양과 지하수에서도 미세플라스틱이 발견되어 미세플라스틱 환경오염 관련 연구의 중요성이 크게 대두되고 있다. 주로 ㎛ - nm의 작은 입자로 존재하는 점토광물과 금속산화광물은 표면적이 넓어 미세플라스틱에 대한 흡착력 등 화학 반응도가 매우 높기 때문에, 광물표면 상호작용은 토양과 지하수 환경 내 미세플라스틱의 거동을 결정하는 중요한 역할을 할 수 있다. 따라서, 광물과 미세플라스틱 간의 상호작용에 대한 환경광물학 연구는 미세플라스틱 거동 예측 기술개발 및 오염대책 마련에 핵심이 되는 연구분야라 할 수 있다. 광물표면과 미세플라스틱(특히, 나노플라스틱) 연구에는 분자-나노수준의 분석기술이 요구된다. 이번 기술보고에서는 나노그람(=10-9 g) 수준의 질량 변화를 실시간으로 측정할 수 있는 초정밀 분석기기로, 광물표면에 흡·탈착되는 미세플라스틱 및 나노플라스틱의 미세한 질량 변화를 측정할 수 있는, 수정진동자미세저울(quartz crystal microbalance, QCM)을 소개한다. QCM 작동원리를 소개하고, 대표적인 QCM 연구결과와 기존 컬럼 실험과의 장단점을 비교하여 미세플라스틱 연구에 QCM 활용 가능성을 논의한다.