• Journal of KIISE:Information Networking
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• v.32 no.6
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• pp.659-667
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• 2005

A Mobile Ad Hoc Network(MANET) is a multi hop wireless network with no prepared base stations or centralized administrations, where flocks of peer systems gather and compose a network. Each node operates as a normal end system in public networks. In addition to it, a MANET node is required to work as a router to forward traffic from a source or intermediate node to others. Each node operates as a normal end system in public networks, and further a MANET node work as a router to forward traffic from a source or intermediate node to the next node via routing path. Applications of MANET are extensively wide, such as battle field or any unwired place; however, these are exposed to critical problems related to network management, node's capability, and security because of frequent and dynamic changes in network topology, absence of centralized controls, restricted usage on network resources, and vulnerability oi mobile nodes which results from the special MANET's character, shared wireless media. These problems induce MANET to be weak from security attacks from eavesdropping to DoS. To guarantee secure authentication is the main part of security service In MANET because networks without secure authentication are exposed to exterior attacks. In this paper, a multistage authentication strategy based on CGSR is proposed to guarantee that only genuine and veritable nodes participate in communications. The proposed authentication model is composed of key manager, cluster head and common nodes. The cluster head is elected from secure nodes, and key manager is elected from cluster heads. The cluster head will verify other common nodes within its cluster range in MANET. Especially, ID of each node is used on communication, which allows digital signature and blocks non repudiation. For performance evaluation, attacks against node authentication are analyzed. Based on security parameters, strategies to resolve these attacks are drawn up.

• Journal of dental hygiene science
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• v.15 no.2
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• pp.153-158
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• 2015

The aim of this study was to provide practical information regarding career exploration to dental hygiene students. This study interviewed 15 senior dental hygienists (graduates of Y University Dental Hygiene program) who have worked in non-clinical fields for about three months from January 14, 2014 to April 28. The most frequently mentioned pieces of information that the senior dental hygienists wanted to convey to dental hygiene students were as followed. Contrary to popular belief, clinical experience was also required in non-clinical fields as the importance of clinical experience was quite often and widely emphasized and applied in such fields. High academic excellence and clinical performance were expected of junior dental hygienists and the senior dental hygienists expressed their hope for their juniors to pioneer new fields and areas of work that a dental hygienist can do. Most of the senior dental hygienists pointed out that to develop technical tools for career exploration as early as possible, such as during undergraduate years and to think about which career path to take, whether it is clinical or academic were significantly important factors for desirable career outcomes. Based on the results of this study, undergraduate dental hygiene students should be provided with opportunities to consider and explore various career paths during their undergraduate years and to communicate with their seniors for hands-on experience-based advices. This would in turn broaden each student's perspective beyond their knowledge or thought about the professional filed of dental hygiene. It was found that the majority of the senior dental hygienists agreed that their clinical experience was the source of their self-competence as a dental hygienist. Our study could be utilized as a valuable resource for future dental hygienists who wish to work in non-clinical fields.

• The Journal of Society for e-Business Studies
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• v.22 no.2
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• pp.123-136
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• 2017

The evaluation and analysis method of information system (IS) is studied from the system perspective, the user perspective, and the management viewpoint. The detailed analysis method performs qualitative evaluation by user questionnaire or expert opinion. In this study, Measures the productivity and the effect of building administrative information systems. In the previous study, qualitative productivity and universal effect indicators were used, but in this study, quantitative productivity indicators and indicators specific to administrative complaints were selected. KONEPS, an administrative service system, used electronic contract records and information recorded in the intermediate process. The information was converted into the number of days, and the productivity based on the input manpower was calculated. The effect analysis analyzed the questionnaire related to civil affairs, which is the goal of the administrative work system. Each factor was divided into reflective structural variable and formal structural variable, and internal consistency and multi-collinearity were diagnosed. In order to verify the model, the influence of the work was set as a hypothesis, the reliability was verified according to the descriptive statistics method, the influence was measured through the regression analysis, and the model was analyzed by the multiple regression model path coefficient. Model validation methods are Chi-square (df, p), RMR, GFI, AGFI, NFI, CFI and GFI as indicators according to CFA.

• Journal of the Korea Institute of Building Construction
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• v.9 no.4
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• pp.111-117
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• 2009

Considering the entire critical path, underground works in construction projects occupy a large part of the total construction period, as well as a large part of the construction costs. Particularly in the downtown area, the scale of underground work has been increasing every year. Currently, underground retaining walls, which are built at construction sites, require many skilled workers, and the works are being undertaken by means of the Euroform+Soldier system, which is quite disadvantageous in terms of the construction period. In order to complement this, forms made of new materials and new construction methods have been developed. Now more than eyer, the shortening of construction periods and the reduction of construction costs is required. Considering this, in this study, the researcher has tried to compare the Euroform+Soldier system, which has been the system most frequently used on construction sites, to the non-supporting form system, which has been used on the sites of civil engineering work. The results of the research revealed that although the Euroform+Soldier system was advantageous from the perspective of material costs, it was disadvantageous in terms of labor costs. It is thought that an additional study on a method for reducing the material costs is required, so as to revitalize the application of non-supporting forms to the construction site.

• Korean Journal of Family Social Work
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• no.54
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• pp.41-75
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• 2016

This study explored the impact of daily hassles and the mediated effect of spiritual well-being and the moderated effect of coping styles on health and depression of middle-aged women. Subjects for this study were 230 Christian midlife women attending in the 10 churches on the metropolitan area. The data was analyzed using path analysis and moderator effect model with the structural equation modeling. Daily hassles are found to act as causes that damage physical or mental health and also elevate the level of depression. Daily hassles have a direct impact on health and depression, and at the same time, they also produce a partial mediation effect on spiritual well-being as a mediation factor. In other words, daily hassles impede spiritual well-being, and the deteriorated spiritual well-being, although its connection to physical health is not clear, is shown to damage mental health and elevate the level of depression. Analysis of coping styles related to the relationship between daily hassles and health and depression showed that, of the 12 coping styles, three, namely, self-criticism, positive interpretation and self-control, produced significant buffering effects. This study hopes to reveal the mediation factors that can minimize negative impact in the relationship between middle-aged women's daily hassles and healthiness and provide the basic material for figuring out practical implications and policy measures regarding the issue.

• The Journal of the Korea Contents Association
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• v.21 no.4
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• pp.463-472
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• 2021

The purpose of this study is to find a way for social welfare organizations to actively cope with environmental changes such as the corona incident according to the work coordination theory that work performance improves when actively coping with environmental changes. In other words, the mediating effect of member agility in the relationship that participatory decision-making affects job performance was identified. The subjects of the survey were workers in welfare centers in the metropolitan area and Chungcheong area, and 310 questionnaires were analyzed, and confirmatory factor analysis, research model analysis, and mediation effect verification were conducted to verify the hypothesis. As a result of the study, participatory decision-making had a significant positive effect on member agility and job performance. In addition, it was confirmed that the partial mediation model including the path that participatory decision-making directly affects job performance and the indirect effect that is linked to job performance after first affecting the agility of members is appropriate. The study has academic significance in that it verifies the effect of participatory decision-making and agility necessary for social welfare organizations, and suggests ways to improve participatory decision-making and agility in hiring, evaluation, and education of employees in social welfare organizations. In this respect, significance can also be found in practical terms.

• Journal of the Korean Society of Marine Environment & Safety
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• v.26 no.7
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• pp.787-797
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• 2020

The marine officer plays a pivotal role in the shipping organization as a professional who performs a complex and diverse function. On the sea, unlike land duty, the possibility of turnover increases due to characteristics such as living in isolated spaces, continuous shift work during a set sailing period, high intensity work tension, stress, and social isolation. In this study, the impact of the organization's civic actions on the intention of turnover as a mediator of organizational immersion was divided into three groups of large companies, small and medium-sized enterprises, and public enterprises to check the differences between each category in a structural manner. Analysis showed that there were statistically significant differences between the groups in loyalty and turnover intention when the sub-factors of organizational commitment and organizational citizen behavior of the marine officer, and the size of turnover intention were included. Organization citizen behavior did not directly affect turnover intention, but when indirect effects were included, there was an effect through loyalty, and relationship-oriented organizational citizen behavior negatively affected turnover intention through loyalty. Excluding public enterprises, the non-standardization path coefficients were -0.229±0.117 and -0.319±0.068, respectively, showing a statistically significant effect in large companies and SMEs. These results indicate that in order to lower the employee turnover intention in large corporations and small and medium-sized shipping companies, it is necessary to consider not only organizational citizen behavior but also measures to increase organizational commitment.

• Korean Journal of Social Welfare
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• v.67 no.2
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• pp.85-112
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• 2015

This study examined the relationship structure among personal and social cognitive factors contributing to professional help-seeking decisions to relieve distress of those in low-income, then suggested an appropriate model to inform knowledge for better social work practice. Using data of a purposive sampling from 331 low-income people, covariance structural analyses were conducted in two stages of model exploration, one for TPB model and another for its extended model including the level of distress, family support, and willingness. As results, in the path analyses with the observed variables of the basic components of the TPB, subjective norm showed the strongest effect on the intention, following by attitudes towards help-seeking, then behavioral control the least; in turn both the intention, positively, and behavioral control, negatively, contributed to help-seeking decisions. In the second stage of the path analyses with the extended model of the TPB, each of distress and family support demonstrated direct positive effect on each of attitudes, subjective norm, and behavioral control; each of the attitudes, subjective norm, and behavioral control showed positive effect on both intention and willingness; in turn, while intention showed strong positive effect on help-seeking decisions, willingness had no significant effect and behavioral control had negative effect on decisions. There were significant indirect effects of behavioral control on intention through willingness and of willingness on decisions through intention. These results suggested that the TPB model is useful for modeling help-seeking decisions through personal and social cognitions, especially the significance of subjective norm implied the importance of social cognition for the people in low-income with distress. Further, it was implied that the extended model needs to address particularity of those people in low-income and the mechanism shown by behavioral control and willingness implied the importance of practicing respect for the client's autonomy and will for self-support in social work practice.

• Journal of the Korean Institute of Landscape Architecture
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• v.45 no.4
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• pp.81-91
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• 2017

The purpose of this study is to establish a system of planning elements necessary for effective healing garden. We suggested new planning parts and elements for healing garden through analyzing prior literature and evaluated the importance of planning elements through expert surveys. The results of the study are stated as follows. First, we suggested five planning parts and 19 planning elements. $\LARGE{\cdot}$ Planning parts: Physical environment, social environment, cognitive environment, functional environment, psychological environment. $\LARGE{\cdot}$ Planning elements: Plant planting, garden view, hydroponic space, shade space, work space, recreation space, community space, exercise space, landmark element, sign system, safe facilities and materials, disaster safety facility, universal design, accessible path, economical maintenance, sight openness, privacy guaranteed, variety of resting space, artistic element. Second, as a result of analyzing the importance of planning elements, the first place was the planting, the second place was the safety facilities for the disaster, and the third was diversity of rest space. In addition, the artistic elements and the landmark elements were ranked 18th and 19th, respectively. Third, we evaluated the level of importance of planning elements and classified it into three groups. The most important A group included two elements(plant planting, disaster safety facility), the next important B group included eleven elements(variety of resting space, community space, hydroponic space, universal design, safe facilities and materials, economical maintenance, accessible path, privacy guaranteed, garden view, work space, sight openness) and the less important C group included six elements(shade space, exercise space, recreation space, sign system, artistic element, landmark element). We suggest that, in creating a healing garden, the two elements in A group are essential elements and the eleven elements in B group should be importantly applied. In addition, the six elements in C group are recognized as arbitrarily selectable elements due to the relatively low importance levels.

• Journal of dental hygiene science
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• v.12 no.1
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• pp.63-70
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• 2012

The purpose of this study was to research sociodemographic characteristic, work-concerned characteristic, health behavior, life stress, psychosocial stress, job stress and self-esteem of dental hygienists and to find their effects on cortisol level in saliva. The target of this study is 219 dental hygienists registered in Daegu and Gyeongbuk Dental Hygienists Association as of February 2010. For life stress, there was significant difference depending on working years of current job(p<0.05), self health status and regular meal(p<0.01). For psychosocial stress, there was significant difference depending on age(p<0.05), daily working hours(p<0.01), self health status, sleeping hours, regular meal and hobby and leisure activity(p<0.01). For job stress, there was significant difference depending on academic background (p<0.05), job experience, position, man power appropriateness in department and working years of current job(p<0.05). For cortisol level in saliva, extra working days(p<0.05) and self health status(p<0.05) showed significant difference and job stress and cortisol level in saliva showed the negative correlation(p<0.01). Health behavior gave a significant effect to life stress by path coefficient -36.807(p<0.05) and that to psychosocial stress by path coefficient -5.209(p<0.001). And health behavior also gave a significant effect to self-esteem by path coefficient 0.561(p<0.05). Life stress gave a significant effect to psychosocial stress by 0.012(p<0.05) with self-esteem to psychosocial stress by -2.437(p<0.001) and psychosocial stress to job stress by 0.523(p<0.001). Job stress gave a significant effect to cortisol level in saliva by -0.060 (p<0.05). It was found that the most significant factor that affects cortisol level in saliva was job stress, but showed negative correlation. It can be assumed that chromic job stress cause shortage in cortisol excretion, and caused lower cortisol level in saliva.