• The korean journal of orthodontics
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• v.28 no.4 s.69
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• pp.547-561
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• 1998

Obstructive sleep apnea (OSA) is a disorder characterized by repetitive episode of upper airway collapse during sleep. Recent studies showed that not only the anatomic factors but the physiologic factors of the upper airway also have effcts on the occurrence of apnea and that the genioglossus muscle also plays an important role in the maintenance of the upper airway. A variety of therapies were performed to treat OSA, and among them the use of mandibular repositioning appliances showed reasonable results. But there is still a lack of research on the structural and physiological mechanism upon the use of mandibular repositioning appliances. The author selected 26(male 17, female 9) OSA patients that came to the Yonsei University Dental Hospital, Department of Orthodontics, and 20 normal adults (male 10, female 10) and took cephalometric radiographs of them in a supine position before and after the placement of the mandibular repositioning appliance to see the structural changes of the upper airway and compare the therapeutic effects between the two groups. We also studied the waking genioglossus muscle activity in OSA patients and investigated the difference in the electromyogram of the genioglosssus muscle upon the change in body posture and the use of mandibular repositioning appliance. Following results were obtained. 1. Among the cephalometric measurements of the upper airway structure, the length of the soft palate, maximum thickness of the soft Palate and SPAS, MAS, VAL, H-H1, MP-H showed statistically significant differences between the normal and OSA groups, but the IAS and EAS showed no statistically significant differences between the two groups. 2. In both the normal and OSA groups, as the epiglottis moved forward on wearing the mandibular repositioning appliance, the epiglottis level of the upper airway increased and the maximum thickness of the soft palate changed and the hyoid bone also moved forward, but the IAS in both groups showed various results and the effect of the mandibular repositioning appliance on the structure of the upper airway was different in the two groups. 3. Upon changing the position, the electromyogram of the genioglossus muscle showed a increasing tendency but there was no statistically significant differences, and when the mandibular repositioning appliance were worn there was a statistically significant increase in the electromyogram of the genioglossus muscle in both the upright and supine positions. The mandibular repositioning appliances not only have an effect on the anatomical structure of the upper airway but also on the physiology of the upper airway. There are different responses to the use of mandibular repositioning appliance between the normal and OSA groups therefore it could be considered to have the different physiology of the upper airway between the two groups.

• The Journal of Society for e-Business Studies
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• v.17 no.4
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• pp.69-93
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• 2012

Various influence-related relationships in Social Network Services (SNS) among users, posts, and user-and-post, can be expressed using links. The current research evaluates the influence of specific users or posts by analyzing the link structure of relevant social network graphs to identify influential users. We applied the concept of mutual interactions proposed for ranking semantic web resources, rather than the voting notion of Page Rank or HITS, to blogosphere, one of the early SNS. Through many experiments with network models, where the performance and validity of each alternative approach can be analyzed, we showed the applicability and strengths of our approach. The weight tuning processes for the links of these network models enabled us to control the experiment errors form the link weight differences and compare the implementation easiness of alternatives. An additional example of how to enter the content scores of commercial or spam posts into the graph-based method is suggested on a small network model as well. This research, as a starting point of the study on identifying influential users in SNS, is distinctive from the previous researches in the following points. First, various influence-related properties that are deemed important but are disregarded, such as scraping, commenting, subscribing to RSS feeds, and trusting friends, can be considered simultaneously. Second, the framework reflects the general phenomenon where objects interacting with more influential objects increase their influence. Third, regarding the extent to which a bloggers causes other bloggers to act after him or her as the most important factor of influence, we treated sequential referencing relationships with a viewpoint from that of PageRank or HITS (Hypertext Induced Topic Selection).

• Journal of Korean Academy of Fundamentals of Nursing
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• v.4 no.1
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• pp.147-162
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• 1997

This study was attempted to provide the basic data for nursing intervention to improve the psychosociological adaptation of patients receiving chemotherapy for breast cancer by examining relationship between anxiety and hopelessness that they are experiencing and family support, in order to help them successfully cope with various psychological problems. This study was carried out with 93 breast cancer patients who are receiving chemotherapy in the injection treatment room of K University Hospital located in the downtown of Taegu after having underwent mastectomy in the hospital between December 1995 and August 1996. This study used the systematized questionnaires which contain 7 questions about general characteristics, Spielberger's trait anxiety & state anxiety scale, the tool that WON(1987) modified the hopelessness scale which was developed by Beck et al.(1967) and the family support tool made by TAE(1985). By using the SPSS/PC program, this study obtained the real number and percentage for the general characteristics of the subjects, and mean and standard variation for the degrees of trait anxiety, state anxiety, hopelessness and family support. The correlation between each variables was identified on the basis of the Pearson Correlation, and the degrees of trait anxiety, state anxiety, hopelessness and family support in the general characteristics of the subjects were analyzed by using the t-test, ANOVA, and Duncan test. The results of this study were summarized as follows. In the general characteristics of the subjects, most of each group were 51 years old or more and the middle class in income, had educational background under elementary school, no job, Buddhism in religion and spouse, and were receiving chemotherapy using MTX and 5FU. It was shown that the degree of the subjects' trait anxiety is, on an average, 50. 29, state anxiety 49. 68, hopelessness 51. 46 and family support 34. 28. Both trait anxiety and hopelessness showed normal correlation ; the higher the degree of trait anxiety is, the higher the degree of hopelessness is, while trait anxiety and family support showed reverse correlation ; the higher the degree of trait anxiety, the lower the degree of family support that the subjects perceive is. State anxiety and hopelessness also showed normal correlation ; the higher the degree of state anxiety is, the higher the degree of hopelessness is. Family support and hopelessness showed reverse correlation ; the higher the degree of family support is, the lower the degree of hopelessness that the subjects perceive is. And family support and state anxiety showed reverse correlation but there was a statistically significant difference. The degree of trait anxiety in the general characteristics of the subjects showed a significant difference by age, job and religion, the degree of state anxiety a signigicant difference by job and religion, the degree of hopelessness a signigicant difference by age, educational background and existence or not of spouse. In conclusion, the breast cancer patients receiving chemotherapy perceive anxiety and hopelessness due to several causes such as diagnosis itself or side effects of chemotherapy, so that it is required not only to develop specific nursing interventions including family support to alleviate anxiety and hopelessness but also to apply such interventions to clinical practice.

• Korean Journal of Environment and Ecology
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• v.24 no.3
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• pp.235-248
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• 2010

This study was carried out to the actual conditions and improvement of the eco-forests master plan in South Korea, and suggested its problems and improvement direction. Results from survey and analysis of limiting factors or constraints in the construction plans of eco-forests in Korea revealed that there were highly frequent problems involving site feasibility, topographic aspect, and existing vegetation. The results of survey on the status of land use indicated that the average ratio of the use of private estate was 29.7%, so then it was estimated that a great amount of investment in purchase of eco-forest site would be required. Results from survey on major introduced facilities showed that there was high frequency of introduction of infrastructure, building facility, recreational facility, convenience facility, and information facility, and that there was low frequency of introduction of plant culture system, ecological facility, structural symbol and sculpture, and the likes. There was just one eco-forest park where more than 500 species of plants grew, and the result of investigation indicated that the diversity of plant species in 11 eco-forest parks was lower than the standards for construction of eco-forest. Results from analysis of the projects costs revealed that investment cost in facilities was higher than planting costs, and that a large amount of investment was made in the initial stage of the project. There was no planned budget for the purpose of cultivating and maintaining the plants and vegetation after construction of eco-forest. The basic concepts in construction of eco-forests were established according to the guidelines presented by the Korea Forest Service; however, the detailed work of the project was planned with its user-oriented approach. Then the construction of eco-forest was being planned following the directions, which would lead to development of a plant garden similar to arboretum or botanical garden. Therefore, it is required that the architect who designs eco-forest as well as the public officer concerned firmly establish the concepts of eco-forest, and that, through close analysis of development conditions, a candidate site to fit the purpose of constructing eco-forest be selected, and also a substantive management plan be established upon completion of construction of eco-forest.

• Korean Journal of Environment and Ecology
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• v.23 no.2
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• pp.208-219
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• 2009

This study is to establish a management method for conservation through comparison and analysis on vegetation structures of Pinus densiflora forest around Beopjusa area for past 17-year. The spatial range of the study was $3.6km^2$ from maintenance office to Beopjusa area. The analysis results of the actual vegetation showed that the ratio of vegetation were composed of 64.7% of Pinus densiflora forest, 3.2% of mixed forest of P. densiflora and deciduous broadleaf trees and 5.9% of deciduous broadleaf tree community out of overall area, 360ha. The type of P. densiflora forest were categorized into four communities; community having high potential of succession, community having low potential of it, the community being in the process of succession and community being in the process of natural selection. The succession tendency was in order of the community having low potential of succession(P. densiflora forest), having high potential of it(P. densiflora forest which is deciduous broadleaf trees are dominating in sub-canopy layer), being in the process of succession(P. densiflora-Prunus sargentii and P. densiflora-Quercus serrata community) and being in the process of natural selection(Q. serrata-P. densiflora and Q. aliena-P. densiflora community). In terms of vegetation management, P. densiflora forest having high potential of succession was needed to remove deciduous broadleaf trees in the sub-canopy layer and the community being in the process of succession was required to be pruning the branch in the canopy layer. Lastly, the community being in the process of natural selection was suggested to let it be in succession, since it is hard to be in the status of P. densiflora Forest.

• Korean Journal of Environment and Ecology
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• v.22 no.3
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• pp.230-240
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• 2008

The primary aim of this study is to estimate the home range of a pair of raccoon dogs(Nyctereutes procyonoides koreensis) and to compare with the previous study of raccoon dogs in a rural area of Gurye, the southern part of South Korea. Radiotracking was regularly carried out on 2 raccoon dogs for 2 days every 2 months(in June, August, October and December, 2006). During the 2 days, radiotracking was usually conducted every $1{\sim}3$ hours through day and night. The analysis of tracking data with a total of $46{\sim}64$ bearings showed that the total home range size of the pair was $0.41km^2$, and mean home range size was $0.32km^2$ by 95% minimum convex polygons(MCP) estimate. The home ranges of the male and female were largely overlapping(about $70{\sim}95%$), and the sizes were not very much different from each other. However, there was a big difference between day $(0.01km^2)$ and night-time $(0.35km^2)$ home ranges, and it was largest in summer$(0.56km^2)$ and smallest in winter $(<0.01km^2)$. In addition, the home range of the pair included 1 core area and 4 different feeding areas. In conclusion, our raccoon dog home range data using the same individuals but with more frequent bearings per day and more extended tracking intervals still showed very similar results to the previous study with less frequent bearings per day and more extensive tracking days.

• Korean Journal of Environment and Ecology
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• v.34 no.4
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• pp.345-354
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• 2020

The purpose of this study was to investigate the effects of soil amendment treatments, such as hydroball, and active carbon, and planting Pennisetum alopecuroides for reducing calcium chloride (CaCl₂) of soil leachate and the growth of Pennisetum alopecuroides. The experiment planted Pennisetum alopecuroides in a plastic pot with a diameter of 10 cm and a height of 9 cm in a greenhouse April-October 2018. The experimental group comprised six treatments, including Non-treatment (Cont.), Hydroball (H), Active carbon (AC), planting Pennisetum alopecuroides (P), hydroball + planting Pennisetum alopecuroides (H + P), and active carbon + planting Pennisetum alopecuroides (AC + P). The dissolution of the CaCl₂ concentration 200ml of 10g/L was irrigated once every two weeks. We measured the growth (plant height, leaf length, leaf width, number of leaves), EC, pH, and exchangeable cations (K⁺, Ca²⁺, Na⁺, and Mg²⁺) according to the high concentration of CaCl₂ in the plant and soil leachate. In a treatment with the 'hydroball' amendment, the soil leachate electrical conductivity (EC), and the cation exchangeable were decreased more than those of the control, while the growth of Pennisetum alopecuroides relative growth rate(RGR) increased. Overall, application with the hydroball amendment added the planting of Pennisetum alopecuroides improved the salt reduction effect more than the control group. These results indicate that the application of the soil amendment agent hydroball was suitable soil amendments in accordance with the high concentration of calcium chloride (CaCl₂). Also, Planting Pennisetum alopecuroides is expected to be appropriate for salt-tolerant plant for soil affected by deicing salt agents.

• Korean journal of applied entomology
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• v.26 no.4 s.73
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• pp.229-237
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• 1987

In order to study the biological control of soil-borne disease of sesame, antagonistic isolates of Trichoderma , Bacillus sand streptomyces to Fusarium oxysporum and Rhizoctonia solani were isolated from the rhizosphere soils of sesame plants and some other habitats. Out of the isolates of microorganisms collected a strain of Trichoderma viride was selected as a biological control agent for the study and its effect on the control of damping-off and the seedling growth of sesame was investigated. The results obtained are as follows: 26 percents of Bacillus spp. isolated from the rhizosphere soil of sesame plants showed antagonism to two pathogenic fungi. Important species were B. Subtilis and B. polymyxa. Streptomyces species isolated from the rhizosphere soils of sesame lysed the cell wall of hyphae and conidia of F. oxysporum and reduced conspicuously the formation of macroconidia and chlamydospores of the fungus. 84 percents of Trichoderma spp. isolated from the rhizosphere soil of sesame plants were antagonistic to F. oxysporum and 60 percents of the isolates were antagonistic to both F. oxysporum and R. solani. Trichoderma viride TV-192 selected from antagonistic isolates of Trichoderma spp. was highly antagonistic to F. oxysporum and soil treatment with the isolate reduced notably damping-off of sesame. T. viride TV-192 showed better growth in crushed rice straw, barley straw and sawdust media than F. oxysporum. Sawdust was selective for the growth of T. viride. Supplementation of wheat bran and mixtures of wheat bran and sawdust inoculated with T. viride TV-192 in the soil reduced remarkably damping-off of sesame by F. oxysporum but high density of the fungus TV-192 caused the inhibition of seed germination and seedling growth of sesame. Inhibitory effects of Trichoderma species on seed germination and seedling growth of sesame were different according to the isolates of the fungus. Normal sesame seedlings on the bed treated with the fungus showed better growth than not treated seedlings.

• Management & Information Systems Review
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• v.35 no.3
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• pp.57-79
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• 2016

It is required to derive various conclusions by identifying the type of power and the relationship between SCMs and presenting practical implications. Thus, we can identify the differential effects of each type of power on SCM performance. We can contribute to develop the practical implications at more sophisticated multi-dimension by comparing results of this study with various SCM theories. Through previous studies, the source of power is largely divided into binding power and non-binding power. Binding power is classified into behavior coercion, binding reward and relationship legitimacy. Non-binding power is classified into work expertise, information superiority and value compliance. Enterprises should fully understand and recognize partners within supply chains including understanding of the source of power, imbalance and results. Thus, we look into types of power and effects on trust and commitment, and identify a causal relationship leading to collaboration and SCM performance. Specific research results are as follows. First, the binding power did not give a significant effect to the trust. However, the binding power gave a positively(+) significant effect to the commitment. Second, non-binding power showed a significant effect on both trust and commitment. As a result of analysis on total effects, it was shown that non-binding power gave indirect effects to collaboration and SCM performance. Third, it was shown that both trust and commitment significantly affected collaboration. From the perspectives of social exchange theory and trading cost theory among inter-organizational relationship theory, it may lead to SCM performance of trust, commitment and collaboration. Moreover, it was found that association of each attribute of power led to the significant result. Fourth, it was shown that trust and collaboration significantly affected SCM performance. However, commitment did not directly affect SCM performance, but it indirectly significantly affected SCM performance through collaboration. Proper use of this power can firmly build partnerships between members of the supply chain and induce the improvement on supply chain performance and satisfaction of members.

• Journal of dental hygiene science
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• v.14 no.4
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• pp.580-588
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• 2014

Fluoride use is the best and widespread method for dental caries prevention. The aim of this study was to investigate experience and recognition of fluoride for caries prevention focusing on majors in one university. Four hundred twenty-four university students were selected by convenience sampling with informed consent and answered the questionnaire by self recording type. The subjects except dental hygiene students knew about purpose of fluoride use (84.6%), over the count fluoride rinse (63.2%), fluoride toothpaste (61.5%), professional fluoride application (56.4%) and water fluoridation (43.6%). They experienced over the count fluoride rinse (67.5%), school fluoride rinse (45.3%), professional fluoride application (30.8%), fluoride toothpaste (28.2%) and water fluoridation (12.0%). The main information paths about fluoride were university lectures among dental hygiene students and internet and mass media, followed by nurse-teachers among non dental hygiene students. The ratios of intention to use fluoride were: 67.8% in dental hygiene, 34.9% in health, 51.4% in non-health in case of professional fluoride application for oneself, 93.1% in dental hygiene, 48.0% in health, 50.4% in non-health in case of professional fluoride application for their children, 79.0% in dental hygiene, 51.3% in health, 55.8% in non-health in case of water fluoridation. The subjects to experience and recognize fluoride for caries prevention had more positive intention to use fluoride. The answers of students majoring in health or medical care were not different from non-health, except dental hygiene. Dental professionals should try to let the public know about fluoride use for caries prevention through mass media and internet as well as individual education in dental clinics.