• The korean journal of orthodontics
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• v.30 no.4 s.81
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• pp.413-421
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• 2000

The purpose of this study was to observe the effects of pregnancy on the experimental tooth movement and alveolar bone turnover process of Sprague-Dawley female rat. Sixty rats were divided into pregnant-tooth movement group(P-Tm), normal-tooth movement group(N-Tm) and normal group(N). Maxillary first molar appliances were inserted bilaterally and activated to 40grams. To measure the amount of tooth movement, x-ray was taken 2 times after appliance insertion and before sacrifice. Animals were sacrificed at 1,3,7,14 days(N=5). Just after sacrifice, alveolar bones were collected and frozen immediately for biochemical analysis. Tooth movement was assessed cephalometrically and tartrate-resistant acid(TRAP) and alkaline phosphatase (ALP) activities were measured in extracts of paradental alveolar bone. The results were as follows: 1. The amount of tooth movement in P-Tm group was greater than that of N-Tm group(p<0.01). 2. Alveolar bone ALP of normal tooth movement group was not significantly different from the control, TRAP was significantly different from the control(p<0.01). In normal tooth movement group, alveolar bone ALP was increased gradually and peak(day 7) fell off significantly at day 14(p<0.05). The Peak of alveolar bone TRAP(day 7) fell off slightly, sustained day 14(p<0.01). 3. Alveolar bone ALP and TRAP of pregnant tooth movement group were not significantly different from that of normal tooth movement group. In pregnant tooth movement group, alveolar bone ALP was increased at day 3(p<0.01) and fell off significantly at day 7-14, alveolar bone TRAP were increased at day 3 and sustained day 14. 4. The peak of alveolar bone phosphatases in pregnant tooth movement group(day3) preceded the peak in normal tooth movement group(day7) (p<0.01). According to the above results, we suggested that bone resorption activity was increased in alveolar bone of pregnant rat, and the degree of tooth movement in pregnancy may be greater than that of normal group because of high bone turnover of alveolar bone in pregnant rat.

• Journal of Oral Medicine and Pain
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• v.31 no.3
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• pp.223-229
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• 2006

The objectives of this study was to investigate the amount of tooth ablation and the change of intrapulpal temperature by Er:YAG laser as it relates to pulse energy and pulse repetition rate at the identical power and, thereby, to reveal which of the two parameters strongly relates with ablation efficiency and intrapulpal temperature. Extracted healthy human molar teeth were sectioned into two pieces and each specimen was irradiated within the combination of pulse energy and pulse repetition time at the same power of 3W; $300mJy{\times}10Hz$ group, $200mJy{\times}15Hz$ group, and $150mJy{\times}20Hz$ group. Each specimen comprised ten tooth specimens. A laser beam with conjunction of a water flow rate of 1.6 ml/min was applied over enamel surfaces of the specimens during 3 seconds and the ablation amount was determined by difference in weight before and after irradiation. To investigate the temperature change in the pulp according to the above groups, another five extracted healthy human molar teeth were prepared. Each tooth was embedded into resin block and the temperature-measuring probes were kept on the irradiated and the opposite walls in the dental pulp during lasing. When the power was kept constant at 3W, ablation amount increased with pulse energy rather than pulse repetition rate (p=0.000). Although intrapulpal temperature increased with pulse repetition rate, there were no significant differences among the groups and between the irradiated and the opposite pulpal walls, except at a condition of $150y{\times}20Hz$ (p=0.033). Conclusively, it is suggested that ablation efficacy is influenced by pulse energy rather than pulse repetition rate.

• Management & Information Systems Review
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• v.30 no.4
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• pp.253-292
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• 2011

This study is significant of groping for the autonomous perspective of a medication system for the establishment of harmonious regional labor-management relationship and investigating a plan to minimize previously labor disputes through both analyzing mediation cases and finding out any core issue from the labor-management relationship, with matters experienced in the mediation field when I had served as a mediator. Specially, this study has also objectives to prevent previously any labor dispute through analyzing and minimizing the issue of the labor dispute by case and to establish harmonious labor-management relationship thereby. Further since it is necessary to understand the organization and roles of the regional labor relations commission in order to understand the concrete matters in respect of the labor dispute mediation, this study shall be to explore in detail the matters relating hereto and to acquire general knowledge of mediation through case analysis. Additionally, there is little studies exploring alternative research for the establishment of reasonable labor-management relationship with core issues referred a mediation to the labor relations commission through both the position heightening of the labor relations commission and the analysis of core issues until now. Thus, this study may provide a theoretical base for raising a technique to enhance negotiation skill through acquiring the previous training or full knowledge on the approaching manner to be taken by the labor and management in the collective bargaining or wage bargaining on the basis of items analyzed by core issue. The heightening perspectives to be acquired through the analysis of 50 or more mediation cases are as follows. First, it deems to be important what position each mediation party takes. Second, the information acquired by an investigator in the preliminary investigation before holding the mediation is very importantly utilized in the mediation. Third, the gumption of mediators in charge of the mediation is very helpful for the resolution of a case. Fourth, it shall be preceding to understand dispute issues. After reviewing fully the investigation report of an investigator, if separate review is required, it is tried to hold a separate meeting and then reduce the number of issues asserted by the labor & management and, if the number of such issues is reduced, the mediation may approach to be concluded. Fifth, it shall be kept in mind that any matter other than the scope of the law be based on not the judgement of mediator but the legal interpretation. Sixth, it is necessary for both labor and management parties to take a positive approach so as to make the healthy labor & management relationship anchored. Seventh, notwithstanding the mediators are part-time and take a service attitude, it shall be encouraged to abstain from slandering or inveighing against the mediators because the mediation is taken against oneself. Eighth, it is necessary to convert the management's recognition about a labor union. Ninth, it is necessary to not raise any issue on the matters, such as time-off system and multiple labor union, etc., which are legally enforced. Tenth, it is confirmed that the regional labor relations commission plays a bridge role of narrowing down the issue difference between the labor and management.

• Management & Information Systems Review
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• v.31 no.4
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• pp.167-195
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• 2012

This study focuses on the characteristic of socio-psychological gender of a consumer except a biological gender. Socio-psychological gender is the self-image of a consumer which is related to the gender role. The goal of this study is, first, to examine if socio-psychological gender has more effect on the purchase intention than biological gender. Second, by classifying a group with femininity among socio-psychological gender, it is to examine what kinds of shopping value it aims at. Finally, it is to examine the difference between men and women from the purchase intention according to the circumstances. The result of this study is summarized as follows. First, a consumer can have both characteristics of biological gender and socio-psychological gender. There are masculinity, femininity, bisexuality, and undifferentiated type for the classification of socio-psychological gender. This study shows that there is relatively much bisexuality which has masculinity and femininity at the same time. The outcome showed that the purchase intention was higher for the product which corresponds to socio-psychological gender of a consumer than biological gender. Second, it indicated that a group with femininity pursued pleasurable shopping as compared to a group with masculinity. By contrast, it showed that a group with masculinity aimed at practical shopping more greatly. Finally, it showed that while women are less sensitive to the purchase intention at the male-dominated circumstances, men's purchase intention get lower at the female-dominated circumstances.

• Management & Information Systems Review
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• v.35 no.4
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• pp.169-184
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• 2016

Deferred tax assets (liability) in a company's financial statements are to reflect the temporary difference between taxable income and accounting income and therefore can provide useful information as a proxy for discretionary accruals. In addition, deferred tax assets allow a company to manage its earnings by reviewing the feasibility of the assets' recognition. As such, this study focused on deferred tax assets to examine their relationship with discretionary accruals, which were measured by a modified Jones model (Dechow et al. 1995), and investigated the impact of audit quality on this relationship. In order to control for the effects of tax rate change and measurement credibility, deferred tax assets of 2,670 non-financial firms from 2009 to 2010 were collected as samples for the study. The results of the empirical analysis are as follows. First, the samples as a whole indicated that deferred tax assets have a negative relationship with discretionary accruals in a general sense, but a high-quality audit did not reveal a significant relationship between them. Second, the 1,379 samples with negative discretionary accruals did not reveal a significant relationship between deferred tax assets and discretionary accruals; however, the result showed a significant negative relationship under a high-quality audit. These findings suggest that in the case of negative discretionary accruals, a high-quality audit restricts an earnings management technique that utilizes deferred tax assets and that the assets can be a useful tool for detecting discretionary accruals. The present study is meaningful in that, unlike previous research, it combined the two contrasting roles of deferred tax assets-that of an earnings management detector and an earnings management tool-to examine their general relationship. The study also suggested that audit quality could influence the usefulness of deferred tax assets in providing information on discretionary accruals.

• Management & Information Systems Review
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• v.35 no.4
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• pp.1-19
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• 2016

The researchers in strategic management have focused on identifying the effects of CEO's demographic characteristics and experience on the strategic choices and performance of firms. On the other hand, they have failed to identifying the effects of CEO's psychological characteristics on them because of the difficulties over data collection and measurement for variables. To overcome this limitation of prior researches, this study is designed to achieve two specific objectives. The first is to examine the effect of CEO narcissism on diversification strategy and performance of listed corporations on Korean securities market in an economic downturn. The other is to examine the moderating effects of various corporate governance systems that are related to board and/or ownership structures on those relationships. The empirical setting for this study was drawn from a multi-year(2011~2014) sample of large listed corporations in Korean securities market. To achieve the objectives, the hypotheses of research are analyzed by implementing multiple regression analyses in two separate models. The results of these analyses show that CEO narcissism is positively related to the diversification of listed large corporations in Korean securities market. Regrading the moderating effects, the stake of institutional investors weakens the positive relationship between CEO narcissism and firm's diversification. The findings of this research imply that CEO narcissism can intensify the tendency of Korean corporations to adopt high-risk and high return strategy in an economic downturn. Thus, firms might be able to use CEO narcissism to drastically restructure the business portfolio in an economic downturn. However, Korean corporations should be very cautions to maximize the positive effect of CEO narcissism. They might be use the institutional investors as their corporate governance system to monitor and control the opportunism of CEO in the decision for diversification in an economic downturn.

• Management & Information Systems Review
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• v.35 no.4
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• pp.251-268
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• 2016

The present study has the purpose of analyzing the relationship between entrepreneurial characteristics and success factors of small-scale start-up founders as well as the relationship between success factors and performances of start-up businesses. It is also aimed in this study to determine the structural effects of start-up founders' characteristic upon their performances and by thus, to provide those who prepare for and/or have been operating start-up business with suggestions for stable and successful start-up as well operation. The study resulted in the following outcomes: First, the analysis of the relationship between characteristics and success factors of start-up business found that the empirical characteristics of small-scale start-up business founders might influence every factor for their success including the financial conditions as well as management of shops, products and service. Their psychological characteristics, however, turned out to have influence upon the management of products and service only, but not upon the financial conditions and management of shops, a result implying that the higher desire and creativity small-scale start-up business founders have, the more probable the start-up businesses become successful. Second it was learned from the analysis of the relationship between success factors and performances of start-up businesses that such success factors of start-ups as financial conditions as well as management of shops, products and service could exercise impact upon their performances, signifying that the exact decision making of small-scale start-up founders might affect the performances of small-scale start-up businesses. Third, the analysis of the relationship between entrepreneurial characteristics and performances of start-up founders revealed that both empirical and psychological characteristics of start-up founders might have influence upon the performances of start-up businesses, leading to the conclusion that small-scale start-up founders could achieve higher performances in their start-up when they are highly aware of empirical and psychological characteristics for start-up as part of entrepreneurial characteristics.

• Management & Information Systems Review
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• v.36 no.5
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• pp.61-83
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• 2017

The purpose of this study is to investigate the mediating effects of psychological empowerment between participative leadership and creative behavior. Especially, it aims to analyze the unidimension and multidimension of psychological empowerment in an integrated manner, and to suggest effective practice of participative leadership together with theoretical and methodological implications. In this study, the dependent variable was measured separately with time lag as a method to solve the common method bias that can be shown by the self-report type survey method, and positive emotions and negative emotions expressing emotional states in job situations were employed as control variables along with rank. A total of 283 questionnaires were collected from employees who work for companies in various industries with more than 300 domestic employees. SPSS PROCESS macro program('model 4') was used for statistical analysis. Results, First, the full mediation effect of psychological empowerment(unidimension) was confirmed in the relationship between participative leadership and creative behavior. Second, the analysis of the multidimension of psychological empowerment revealed the full mediating effect of meaning, self-determination, and impact, and the mediating effect of competence was not significant. Third, as a result of comparing the mediating effects of unidimension of psychological empowerment and the mediating effects of multidimension, the magnitude of mediating effect of unidimension was found to be much greater than mediating effect of multidimension. And The magnitudes of the three multidimensional mediating effects were similar. This is a case in which the motivational model of participative leadership revealed in the overseas study is proven in the domestic management environment and is significant in that it is the basis of future research. Based on the results of the empirical studies, the implications and limitations of the study and future research directions are presented.

• Management & Information Systems Review
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• v.36 no.5
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• pp.27-44
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• 2017

The purpose of this study was to empirically verify the effect of social entrepreneurship on market orientation. total of 500 questionnaires were distributed to workers in social enterprise and preliminary social enterprise. 202 questionnaires were used for final validation of research model, The hypotheses set in this study were validated through SPSS18.0 and LISREL8.3 based on the research model. The results showed that all hypotheses were accepted, except for 5 hypotheses(Hypothesis 1-1, Hypothesis 1-2, Hypothesis 1-3, Hypothesis 1-6, Hypothesis 1-9). First, we examined the effect that empathy might have on market orientation in connection with social entrepreneurship. The results suggested that empathy did not have a statistically significant effect on customer-orientation, inter-department cooperation and coordination, and competitor orientation. Second, we examined the effect that innovativeness might have on market orientation in connection with social entrepreneurship. The results showed that innovativeness had a positive(+) effect on customer-orientation and inter-department cooperation and coordination but did not have a statistically significant effect on competitor-orientation. Third, we examined the effect that risk-taking might have on market orientation in connection with social entrepreneurship. The results implied that risk-taking had a positive(+) effect on customer-orientation and inter-department cooperation and coordination but did not have a statistically significant effect on competitor-orientation. Finally, the relationship among market orientation variables was like this: The inter-department cooperation and coordination had a positive(+) effect on both customer-orientation and competitor-orientation. The results of this study are expected to provide a useful basis for overall understanding about the effect of social entrepreneurship on market orientation and present important theoretical and practical implications.

• Management & Information Systems Review
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• v.36 no.5
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• pp.121-149
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• 2017

This study looks into individual entrepreneurship engaged in an enterprise; the effect of creative efficacy and internal and external networks on organizational commitment based on the previous studies. The hypothesis, the internal and external networks constructed in social context by individuals in the relationship between individual entrepreneurship and organizational commitment; and mediating effect through creative efficacy obtained by the previous experience can be in existence, is to be confirmed through an empirical study. The analysis data is collected from 244 of currently working employees via a survey. The determination of employee-oriented study is summarized as follows: first, the promotion of employee's individual entrepreneurship is significant as well as of the leader for the result of organizational commitment, because there are positive effects between the individual entrepreneurship and organizational commitment. Second, the internal and external networks owned by individuals affect one's own outcome as the internal and external networks of enterprise mediate the relationship between individual entrepreneurship and organizational commitment. Third, it is confirmed that the confidence in individual creativity is an essential factor as creative efficacy exhibits a mediating effect in relationship between individual entrepreneurship and organizational commitment. Particularly, it is verified that an enterprise is in need to expand education or programs not only for networks leading to an outcome but also for creativity improvement of affiliated individuals from the fact that creative efficacy, a hybridized concept of creativity and self-efficacy studied in the previous research, mediates the relationship between individual entrepreneurship and an outcome. In the conclusion, additional implications are offered; the thresholds and frameworks for the study are discussed.