• 대한기계학회:학술대회논문집
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• 대한기계학회 2001년도 춘계학술대회논문집A
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• pp.223-230
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• 2001

The Monkman-Grant (M-G) and its modified parameters were estimated for modified type 316LN and $9{\sim}12Cr-1Mo$ steels with chemical variations. Several sets of creep data were obtained by constant-load creep tests in $550-650^{\circ}C$ ranges. The relation parameters, m, $m^*$, C and $C^*$ were proposed and discussed for two alloy systems. In creep fracture mode, type 316LN steel showed domination of the intergranular fracture caused by growth and coalescence of cavities. On the other hand, the Cr-Mo steel showed transgranular fracture of the ductile type caused from softening at high temperature. In spite of the basic differences in creep fracture modes as well as creep properties, the M-G and its modified relations demonstrated linearity within the $2{\sigma}$ standard deviation. The value of the m parameter of the M-G relation was 0.90 in the 316LN steel and 0.84 in the Cr-Mo steel. The value of the $m^*$ parameter of the modified relation was 0.94 in the 316LN steel and 0.89 in Cr-Mo steel. The modified relation was superior to the M-G relation because the $m^*$ slopes almost overlapped regardless of creep testing conditions and chemical variations to the two alloy systems.

• Journal of Chest Surgery
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• 제25권8호
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• pp.863-870
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• 1992

The low profile Ionescu-Shiley pericardial xenograft valve had been initially introduced to have improved hemodynamic performance and expected superior durability, However, subsequent clinical reports and laboratory studies have repeatedly indicated early failure of the valve from mechanical reasons in valve design, A total and consecutive 169 patients underwent isolated MVR with the low profile Ionescu-Shiley valve at Seoul National University Hospital from November 1984 to October 1989 [Group ISLM]. Five patients [3.0%] died within 30 days of surgery, and early survivors were followed up for 734.9 patient-years [Mean$\pm$SD, 4.9$\pm$2.0 years], Late mortality rate was 0.136% /patient-year [pt-yr], Linearized incidences of major complications were: 0.953% embolism /pt-yr; 0.680% bleeding /pt-yr; 0.272% endocarditis /pt-yr; and 0, 408% primary tissue failure [PTF] /pt-yr, The actuarial survival was 99.4$\pm$0.6%, and probabilities of from thromboembolism and from PTF were 90.7$\pm$4.6% and 95.9$\pm$2.6% at 8 years, respectively These results were compared with the clinical data from the 291 patients of isolated MVR with the standard Ionescu-Shiley valve at the same hospital during the period between October 1978 and June 1983 [Group ISUM], Group ISUM included 11% of patients younger than 15 years of age, whereas Group ISLM did no patient of this age. The mean age at the time of surgery was significantly younger in Group ISUM than one in Group ISLM [P<0.001]. Differences were not statistically significant in operative mortality, mean follow-up period and linearized incidences of thromboembolism, bleeding and endocarditis, between two groups, However, the linearized rate of PTF was lower [P<0.001] and probabilities of freedom fro PTF higher [P<0.001] in Group ISLM at least up to postoperative 8 years. While the features of PTF of the standard valve was predominantly degeneration with calcification and stenosis, the ones of the low profile valve was cusp tear and incompetence. It remains, however, to be seen whether the low profile valve fails mostly from mechanical reason, and further follow-up will still be necessary to determine the differences in mode of PTF of two valves.

• 대한불안의학회지
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• 제10권1호
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• pp.44-51
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• 2014

Objective : The amygdala has been considered to be a critical region in the pathophysiology of social anxiety disorder, but subregional connectivity pattern has not been examined yet despite lots of previous functional neuroimaging studies. Methods : Resting-state functional magnetic resonance imaging data was obtained in 19 patients with social anxiety disorder and 20 normal controls, and default mode functional connectivity with each of basolateral, centromedial and superficial areas of the amygdala was measured and compared between the two groups. Results : Differential amygdala-based networks between the two groups were distributed to all over the brain. In particular, however, a bias on the amygdala-cingulate pathway was observed in the superficial amygdala only. Connectivity strengths between the superficial amygdala and perigenual anterior cingulate cortex were correlated with scores of social interaction and avoidance. Conclusion : Our findings provide new insights into understanding of the intrinsic cognitive bias model of social anxiety disorder. An abnormality in superficial amygdala-anterior cingulate connectivity may influence on cognitive processing of socially-relevant information in social anxiety disorder.

• 대한한의학회지
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• 제26권1호
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• pp.187-194
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• 2005

Objective: Two Korea-mode sport beverages with medicinal herbs added, Saeng Mac San (SMS) and Je Ho Tang (JHT), were developed by the Ginseng Research Group of the Korea Food Research Institute. For their practical usage, we examined their taste tests at rest including sense-analysis (S-A) and preference-inquiry (P-I). Methods: Five beverage-treatments, SMS, JHT and three commercial sport beverages (CSBs) and a control (CON) were offered randomly. Eighty-two subjects under stable control of their taste sense filled out the questionnaires for their S-A and p-I, which were developed by the Exercise Physiology Laboratory of Kyungpook National University. The collected data $(means{\pm}SD)$ were analyzed by repeated measures one-way ANOVA; Tukey' s test was administrated for identification of statistically significant differences (p<0.05). Results: Overall beverage likeability values of SMS and JHT were significantly lower than those of CSBs, JHT lower than CON. Overall flavor values of SMS and JHT were significantly lower than those of CSBs and CON. SMS was similar to CON in the amount of flavor. SMS and JHT were less tart than CSBs and the former was significantly lower than CSBs and CON in four drinkability-related items. Conclusion : SMS rated less than CSBs in tartness and the amount of flavor. JHT was avoided most. Thus, the results indicate that JHT is not fit as a sport beverdge and the overall likeability of SMS must be elevated by way of strengthening its tartness and amount of flavor for practical usage.

• 대한간호학회지
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• 제48권2호
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• pp.208-220
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• 2018

Purpose: The aim of this study was to analyze the effects of neurofeedback training for reducing stress and enhancing self-regulation in late adolescence to identify the possibility of use for nursing intervention. Methods: A nonequivalent control group pre-post quasi-experimental design was used. Participants were 78 late adolescents assigned to the experimental group (n=39) that received the neurofeedback training and the control group (n=39). Data were collected on heart rate variability (HRV) and skin conductance level (SCL) to assess stress-biomarker response. The questionnaire contained 164 items from: Positive and Negative Affect Schedule (PANAS), Symptom Checklist-90-Revised (SCL-90-R) and Self-regulatory Ability scale. The neurofeedback training was based on the general adaptation syndrome and body-mind medicine. The intervention was conducted in a total of 10 sessions for 30 minutes per session with high-beta, theta and sensory motor rhythm training on scalp at central zero. Results: There were significant difference in standard deviation of normal to normal interval (p=.036) in HRV and SCL (p=.029) of stress-biomarker response between the two groups. Negative affect (p=.036) in PANAS and obsessive compulsive (p=.023) and depression (p<.001) in SCL-90-R were statistically significant. Self-regulation mode (p=.004) in self-regulation ability scale showed a significant difference between the two groups. Conclusion: The results indicated that the neurofeedback training is effective in stress-biomarkers, psychoemotional stress response and self-regulation. Therefore, neurofeedback training using neuroscientific approach based on brain-mind-body model can be used as an effective nursing intervention for late adolescents in clinics and communities for effective stress responses.

• 한국과학교육학회지
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• 제16권4호
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• pp.429-440
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• 1996

This study examined the effects of the ARCS model for science education and found a way of improving ARCS while finding any weaknesses. More specific research questions were as follows: 1) Does the ARCS model enhance the learners' achivement in highschool Earth Science significantly?; 2) Does the ARCS model enhance the learners' motivation in highschool Earth Science significantly?; 3) What are the weaknesses of the prescriptions of the ARCS model for designing a lesson, if any?; 4) How can the weaknesses of the prescriptions of the ARCS modeI be overcome? In order to fulfill the purpose of this study, the two major research methodologies were implemented: pretest-posttest control group design and formarive research. This study was conducted in two distinct phases: 1) designing a set of instructions for 4 weeks with the principles of the ARCS model (to find the weaknesses of the ARCS model) and 2) teaching the instructions and checking the effectiveness of the ARCS model by pretest and posttest with control and experimental groups(to find weaknesses of the underlying theory of the ARCS). After the experiment, each group took an achievement test and an attitude test on the given instruction and gathered data were analyzed with t-tests. Also, from each four classes 7$\sim$8 students were randomly sampled and individually interviewed about the instructional effectiveness and their preference on the instructions. The results of this study are summarized as follows: Significant differences between the control group and experimental group are seen in three components; Attention, relevance, and satisfaction. No significant differences are seen in the attitude of confidence. The weakness of the prescriptions of the ARCS model, are insufficient of strategy for 'confidence'. For overcoming the weaknesses of the prescriptions of the ARCS model, developmental type research is needed.

• 복식문화연구
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• 제20권3호
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• pp.347-362
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• 2012

Formatively and artistically aspect, a hybrid can be said to be a phenomenon in which two mutually different genres are combined. Make-up is thought to be very important to arrange the foundation available for predicting and pursuing a flow and direction of future hybrid make-up based on this, by analyzing a flow centering on hybrid trend, which was shown previously. In terms of objectives of this study, the first, aim is to suggest a model for researching make-up by grasping the developmental process and the characteristics of hybrid art through considering an art theory of hybridity, shown in make-up. The second, aim is to design make-up by analyzing trends in make-up style after deconstructing the hybrid genre. The modern make-up design through genre-deconstruction characteristics beyond diverse plurality and genre could be known to be highlighted as aesthetic characteristic by a slight attempt as communication of open space, which connects culture and genre, which had failed to be recognized and was neglected. Empirical research has, produced a work by systematically arranging make-up design. This study, identifies two kind of barrier demolition, such as the class deconstruction and the temporal, spatial disorder centering on genre deconstruction of hybrid. There are infinite possibilities in developing make-up design in line with modern sensation through aesthetic element and symbolic significance through genre deconstruction. It was the expression mode in future make-up, to providing basic data, and to strengthening competitive edge of culture and art.

• 패션비즈니스
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• 제16권2호
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• pp.88-107
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• 2012

Hybrid implies that elements in more than two are combined, and is what is merged and used complexly the technologies and materials in several fields according to the development in scientific technology and the progress in technology. In the formative and artistic aspect, the hybrid can be said to be phenomenon that two of mutually different genres are combined. The function and form in each genre, which were combined at this time, are remained wholly or partially, thereby revealing as well without hiding a fact of having been combined. In the digital communication era, the same time level was integrated into one culture, with destroying the temporal·spatial boundary. As for the objectives of this study, first, the aim is to suggest a model for researching into make-up by grasping the developmental process and the characteristics of hybrid art through considering an art theory of hybrid, which was shown in make-up. Second, the aim is to design make-up by analyzing trend by make-up style after applying the genre deconstruction in hybrid. The modern make-up design through genre-deconstruction characteristics beyond diverse plurality and genre could be known to be highlighted as aesthetic characteristic by a slight attempt as communication of open space, which connects culture and genre, which had failed to be recognized and was neglected. Through the results of this study, it could be known that there is infinite possibility in developing make-up design in line with modern sensation through aesthetic element and symbolic significance through genre deconstruction. Based on these findings, its significance can be said to be in substantially contributing to offering new sight to the design & formative characteristic and the expression mode in future make-up, to providing basic data, and to strengthening competitive edge of culture and art.

• 대한가정학회지
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• 제20권4호
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• pp.193-204
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• 1982

This study attempts to clarify the relationship between mother;s child-rearing practices and children's critical thinking abilities. More specifically this study wants to answer the questions: (a) Is there any relationship between mother's child-rearing practices and children's critical thinking abilities? (b) What dimensions of child-rearing practices are more important for children's critical thinking abilities? (c) Does the developmental process of children's critical thinking abilities show any difference according to the mother's child-rearing practices? This study is based on the conceptual model of child-rearing practices from the cognitive disciplinary viewpoint proposed by Lee et al.(1973). They polarized the child-rearing practices into the“mediated”types. These types were specified along seven dimensions of child-rearing. In general terms, the two types refer to the degree to which mother resorts to the description of concrete and immediate phenomena and immediate expression of momentary impulses, and positively reinforces such behaviors of her children. Two kinds of data were collected from 60 primary school boys and girls, and their mothers. A child-rearing practices questionnaire with 28 items was sent to the mothers. And the children were administered a critical thinking abilities test containing measures of 4 dimensions from the Ahn's Critical Thinking Measurement Technique. The major findings are those (a) the children of mothers who reported to have used more“mediated”types of child-rearing show relatively higher level of critical thinking abilities than their counterparts; (b) of the seven dimensions of child-rearing practices, the most significant are“mode of description”,“rationality-orientation”and“reward and punishment”; and (c) the“mediated”type of child-rearing practices tends to facilitate critical thinking abilities development. In conclusion, it is believed that a further refinement of this study will contribute to the development of child-rearing training program for mothers.

• Restorative Dentistry and Endodontics
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• 제40권1호
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• pp.68-74
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• 2015

Objectives: This study examined the effects of additional acid etching on the dentin bond strength of one-step self-etch adhesives with different compositions and pH. The effect of ethanol wetting on etched dentin bond strength of self-etch adhesives was also evaluated. Materials and Methods: Forty-two human permanent molars were classified into 21 groups according to the adhesive types (Clearfil SE Bond [SE, control]; G-aenial Bond [GB]; Xeno V [XV]; Beauti Bond [BB]; Adper Easy Bond [AE]; Single Bond Universal [SU]; All Bond Universal [AU]), and the dentin conditioning methods. Composite resins were placed on the dentin surfaces, and the teeth were sectioned. The microtensile bond strength was measured, and the failure mode of the fractured specimens was examined. The data were analyzed statistically using two-way ANOVA and Duncan's post hoc test. Results: In GB, XV and SE ($pH{\leq}2$), the bond strength was decreased significantly when the dentin was etched (p < 0.05). In BB, AE and SU (pH 2.4 - 2.7), additional etching did not affect the bond strength (p > 0.05). In AU (pH = 3.2), additional etching increased the bond strength significantly (p < 0.05). When adhesives were applied to the acid etched dentin with ethanol-wet bonding, the bond strength was significantly higher than that of the no ethanol-wet bonding groups, and the incidence of cohesive failure was increased. Conclusions: The effect of additional acid etching on the dentin bond strength was influenced by the pH of one-step self-etch adhesives. Ethanol wetting on etched dentin could create a stronger bonding performance of one-step self-etch adhesives for acid etched dentin.