• Journal of Dental Rehabilitation and Applied Science
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• v.22 no.2
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• pp.125-136
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• 2006

Statement of problem. The success of the bonding between electroforming gold and resin is dependent on the surface-conditioning technique but its effective technique has net been studied widely. Purpose. The purpose of the study was to evaluate the bond strength between the electroforming gold and resin with varying the surface-conditioning technique. Materials and methods. Sixty rectangular shaped metal specimens were made and one side of each specimen were gold hard plated. The sand-blasted specimens were divided into four experimental groups with fifteen specimens in each group and were treated as follows. Group 1: Silicoating (Rocatec, 3M ESPE)+ Sinfony (3M ESPE), Group 2: SR Link+ SR Adoro (Ivoclar Vivadent), Group 3: Tin plating (Microtin, Danville Engineering)+ SR Link+ SR Adoro, Group 4: Tin plating (Micro tin, Danville Engineering)+ Silicoating (Rocatec)+ Sinfony. Shear bond strength at metal-resin interface were measured using universal testing machine. Energy Dispersive x-ray analysis was done and scanning electron microscope images were taken and observed. Results and Conclusion. The following conclusions were drawn. 1. The mean shear bond strength values in order were 11.69MPa (Group 2), 22.35MPa (Group 3), 22.40MPa (Group 1) and 27.71MPa (Group 4). There was no significant difference in Group 1, Group 3 and Group 4(P>0.05). 2. In the EDX line analysis, the Au was detected on the surface of all specimen. $SnO_2$ showed on the surface of Group 2 and $SiO_2$ was detected on the surface of Group 1. 3. Increasing of roughness by sandblasting(Group 2), formation of micro-irregularities and tin crystals by electrolytic tin plating(Group 3) and formation of surface irregularities and $SiO_2$ layer(Group 1,4) were observed in SEM photo. 4. Tin plating(Group 3) and Rocatec treatment(Group 1) showed clinically effective shear bond strength(>20MPa), but when the two surface conditioning method were used together higher bond strength were achieved.

• Physical Therapy Korea
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• v.5 no.2
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• pp.65-80
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• 1998

Parents of handicapped children are experiencing difficulties in their children's care, social isolation, change of life style and lirnited leisure time. Because the parents should take care of the children's daily life, they have lots of psychological and physical stress. Chronic stress of parents puts stress to the other family members and affects the development of children with handicap. The purpose of this study were to identify the level of stress in each of parents of children with motor problem, the characteristics of the children and general information related with the children, and to analyse the stress by reasons. Specially organized questionnaire were used for an investigation method. "Test of stress in mother who has children with chronic illness" by Kim Hee-soon were modified and used. The questionnaire answered by 43 mothers and 35 fathers were analyzed. Data analysis includes frequency analysis, Pearson correlation coefficients, paired-samples t-test and MANOV A by SPSSWIN. The results were as follows: 1) Degree of handicap was most moderate (46.5%), level of motor development was most pull to walk (34.9%), and combined handicap was 69.8%. 2) Sexual distribution represented that 51.2% male and 48.8% female. The cost of physical therapy was 69.8% in no more than 100,000 won. 3) The mean of age, for the mother was 32.8 years and 35.3 years. Level of motor development that mother and father expect was 88.4%, 83% walk alone. 4) Both mother and father experienced stress in other of Part II (changes in father was the illness status of the child and difficulty in taking care of child), Part III (prognosis of the child's condition), Part I (social-personal relationships and the responsibility of the care givers). In the total score of stress, mother's stress is indicated higher level than father's stress. 5) There was no correlationship between characteristics and stress of mother and father. 6) There was no statistically significant difference between characteristics and related general information of children with handicap and stress of mother and father. As a results, the mother of children with handicap are experiencing more stress than the father. Both of parents have the most difficulties in the changes in the illness status of the child and difficulty in taking care of child. This study can be used as resources of education, therapy and counselling for children with handicap and their parents. This study, also, can be used to encourage the quality of Iife for the children with handicapped and their family.

• Korean Business Review
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• v.22 no.1
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• pp.45-75
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• 2009

Previous researches of organizational citizenship behavior have been focused mainly on organizations, and there have been only a few studies on the organizational citizenship behavior of nonprofit organizations. In particular, few empirical studies have been made on the relations among variables affecting the organizational citizenship behavior of profit and nonprofit organizations. Thus, this study attempted comparative analysis. According to the result of the analysis, in profit organizations, the fairness of procedure, emotional commitment and continuous commitment had a significant effect on organizational citizenship behavior, as well as the fairness of distribution and perception of organizational support. In nonprofit organizations, on the contrary, the fairness of distribution, the fairness of procedure, and perception of organizational support were insignificant, and only emotional commitment and continuous commitment had a significant effect on organizational citizenship behavior. This study is meaningful in that it comparatively analyzed the effects of organization members' perception of fairness on organizational citizenship behavior in profit and nonprofit organizations, and its outcome may be utilized as a reference in future researches but it has a problem in external validity that poses a limitation in its generalization.

• Journal of the Korean Institute of Landscape Architecture
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• v.47 no.6
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• pp.67-77
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• 2019

The purpose of this study is to analyze how much particulate matter at the center of the urban park is reduced compared to the entrance of the park, where the particulate matter problem is serious. It also endeavored to analyze the relationship between the space closure rate and particulate matter reduction rate in the center of the park through the collection and analysis of experimental data. Seven flat land type urban neighborhood parks in Suseong-gu, Daegu were measured at the same place for three days. The research results are as follows. First, the center of the urban neighborhood park had an average temperature 1.05℃ lower than at the entrance and an average humidity of 2.57% higher. Second, the rate of fine dust reduction was PM1- 17.09%, PM2.5- 17.65%, PM10- 14.99%. As for the reduction rate of particulate matter, the smaller the size of the park, the greater the reduction rate. In addition, the reduction rate at the center of the park was lower on days when particulate matter concentration based on the weather reports was low. The higher the concentration at the park entrance, the higher the reduction rate was. Third, a higher the rate of space closures at the center of the park resulted in a higher effect of particulate matter reduction. Noting this, the relationship between particulate matter reduction and the space closure rate in urban neighborhood parks was clearly shown. We hope to be the basis for more extensive experimental data collection.

• Korean journal of communication and information
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• v.58
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• pp.55-73
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• 2012

This study is critical research on the forming public opinion of SNS and participation behavior. Twitter is a typical SNS service, free school food and 10.26 re-and by-elections during the formation of public opinion on the impact have been investigated. Formation of public opinion about Twitter's analysis of the first research question, The case of free meals to support the Mayor Oh, rather than against Twitter were influential. 10.26 re-and by-elections Twitter in space, the Park' candidate than Na' candidate has formed a favorable opinion. Power twitterian and twitterian on the behavior of the second study involved analysis of the problem, For free meals, power twitterian were responsible for leading the public opinion. For 10.26 re-and by-elections, Power twitterian were more Park' candidates than Na' candidates. In addition, Park' candidates of twitterians were communicating more. Through traditional media in the process of forming public opinion was swayed by public opinion to the target people simply but SNS age people involved in the production and distribution of the issue and the issue has a leading role.

• The Transactions of the Korea Information Processing Society
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• v.7 no.8
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• pp.2484-2496
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• 2000

High speed switches have been developing to interconnect a large number of nodes. It is important to analyze the switch performance under various conditions to satisfy the requirements. Queueing analysis, in general, has the intrinsic problem of large state space dimension and complex computation. In fact, The petri net is a graphical and mathematical model. It is suitable for various applications, in particular, manufacturing systems. It can deal with parallelism, concurrence, deadlock avoidance, and asynchronism. Currently it has been applied to the performance of computer networks and protocol verifications. This paper presents a framework for modeling and analyzing ATM switch using stochastic activity networks (SANs). In this paper, we provide the ATM switch model using SANs to extend easily and an approximate analysis method to apply A TM switch models, which significantly reduce the complexity of the model solution. Cell arrival process in output-buffered Queueing A TM switch with finite buffer is modeled as Markov Modulated Poisson Process (MMPP), which is able to accurately represent real traffic and capture the characteristics of bursty traffic. We analyze the performance of the switch in terms of cell-loss ratio (CLR), mean Queue length and mean delay time. We show that the SAN model is very useful in A TM switch model in that the gates have the capability of implementing of scheduling algorithm.

• Journal of the Korean Geographical Society
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• v.42 no.4
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• pp.506-525
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• 2007

Incision into bedrock channel is the primary control of landform evolution, but research into bedrock incision process stagnated for long time. Due to the scaling problem of the application of results from flume studies to bedrock channel, there is a strong need to simulate the bedrock incision process with more realistic models. As a part of investigation into controls of bedrock channel incision, three-dimensional changes of rock surface with abrasion was investigated with physical modelling. 18 rock plates were abraded with various sediment particle size and sediment load and abraded surfaces of the plates were scanned with high resolution 3-D scanner. To identify the spatial pattern of erosion of the rock plates, various methods were used. There was no synthetic or holistic method that showed all features of bedrock plate produced by abrasion, so each plate was analyzed using some available methods. Contour maps, shaded relief maps and profiles show that abrasion concentrated on the centre of plate (cross profile) and upstream and downstream edges (longitudinal profile) and eroded area extended inwards. It also found that the cracks and boundaries of forming materials easily eroded than other parts. Changing patterns of surface roughness were investigated with profiles, regression analysis and spectral analysis. Majority of plates showed decrease in small-scale roughness, but it depends on microstructures of the plates rather than general hardness or other factors. SEM inspection results supported this idea.

• Journal of Home Health Care Nursing
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• v.8 no.2
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• pp.135-147
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• 2001

The aim of this descriptive study was to identify the impact of chronic illness on children and their families. Mothers of 177 children with chronic disease were recruited from aged one to 17 years hospitalizing the pediatric nursing unit at one university hospital. 28 questions. a self-complete maternal questionnaire developed by researchers based on literatures and 'The Impact of Childhood Illness Scale' (Hoare & Russell, 1995) assess four aspects of the child's and family's lifestyle with two dimensions for each question. the frequency of the problem and its importance of concern that it cause. In the data analysis. Pearson correlation coefficients and analysis of variance were used to test any association and a statistical comparisons. between individual variables and the impact on child's and family's lifestyle. The results were as follows: 1) There were the higher mean scores on the importance dimension than on the frequency dimension on total impact on child's and family's lifestyle. On the importance dimension. mothers had much higher levels of concern about impact on child's development and adjustment among subscales. On the frequency dimension, mothers had much higher levels of concern about impact on the family daily living on subscales. 2) The impact on child's and family's lifestyle related on individual variables were: (1) On the importance dimension. there was statistically significant low in the impact on child's development and adjustment among subscales in older parent group compared with it of younger parent group. (2) On the frequency dimension. there were statistically significant high in the impact on child's development and adjustment among subscales in the children with leukemia or cancer compared with it of the other children who had another chronic illnesses. And there were statistically significant high in the impact on child's development and adjustment among subscales in less than high school educated mothers compared with it of mothers who was educated college level. (3) On the frequency dimension. There were statistically significant high in the impact on family's daily living among subscales and total impact on child's and family's lifestyle in female children. (4) There was positive correlation between impact on parents daily living and frequency of child's hospitalization on the frequency dimension. but there was negative correlation between the two variables on the importance dimension. (5) There was positive correlation between impact of chronic illness and its treatment and duration of child's hospitalization on the frequency dimension. In conclusion. these results were reflected by the high level of concerns about impact on child's development and adjustment although mothers had frequently responded about the impact on the family daily living. We suggest consistent intervening program that help the family empowering to make children live with and adjust to their chronic illnesses from the point of diagnosis and after discharge from the hospital. We also suggest these results can be utilized as a useful data in the practice of home health nursing for children who have chronic illnesses and their families.

• Korean Journal of Construction Engineering and Management
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• v.12 no.5
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• pp.71-80
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• 2011

Flying net should be installed on every 3 or 4 construction floor from 8m above ground according to the rule. In the apartment housing construction, flying net installation work has been recognized the most dangerous work among the whole works because a small mistake of labors might make their death accident. Sub-contractors specialized in flying net have been developing various flying net types. However, most works of installing flying net as working with the developed system are performed outside the apartment housing, so that the risk of fall in works of installing supports and unfolding net is still high. Furthermore, as using the previously developed flying net labors might bump into the frame or the wire rope for supporting so that it makes secondary accidents. The objective of this research is to produce the proto-type of anti-collision flying net system based on the result of problem analysis on the installation and detachment process and suggest the improved anti-collision flying net system, which is able to improve safety and field applicability by conducting field experiment and analyzing performance.

• Journal of The Korean Association For Science Education
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• v.35 no.3
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• pp.383-393
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• 2015

This study analyzed the 6th grade elementary science textbook 'Science stories' reading process of students by utilizing eye movement tracking techniques. Participants read 3 articles in the new experimental science textbooks and solved 9 problems about each article. By understanding and academic achievement results, participants were divided into high-groups, middle-groups, and low-groups. The results of eye movement characteristics of the high-groups and low-groups had the following differences. Number of fixations and number of regressions were higher in high-groups. Average fixation duration and average regressive fixation duration were longer in low-groups. Fixation time for the key sentence of the article was longer in high-groups. Analysis of a scan path and post-interview, high-groups had frequent regression between sentences and they knew where the core of the article is and paid much attention there. In contrast low-groups are sequentially read most articles and some of them had a leap of abnormal range. Problem-solving approach is also different between groups. In conclusion reading style is associated with the science stories comprehension and students who had more regressions, much core search process, effective attention distribution, high concentration showed better understanding results. Also words or sentences used in textbooks are associated with science stories comprehension.