• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.50 no.12
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• pp.829-838
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• 2022

This study conducts Hypervelocity Impact(HVI) simulations considering space objects with various shapes and different impact angles. A commercial nonlinear structural dynamics analysis code, LS-DYNA, is used for the present simulation study. The Smoothed Particle Hydrodynamic(SPH) method is applied to represent the impact phenomena with hypervelocity. Mie-Grüneisen Equation of State and Johnson-Cook material model are used to consider nonlinear structural behaviors of metallic materials. The space objects with various shapes are modeled as a sphere, cube, cylinder, and cone, respectively. The space structure is modeled as a thin plate(200 mm×200 mm×2 mm). HVI simulations are conducted when space objects with various shapes with 4.119 km/s collide with the space structures, and the impact phenomena such as a debris cloud are analyzed considering the space objects with various shapes having the same mass at the different impact angles of 0°, 30° and 45° between the space object and space structure. Although space objects have the same kinetic energy, different debris clouds are generated due to different shapes. In addition, it is investigated that the size of the debris cloud is decreased by impact angles.

• The Journal of the Korea Contents Association
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• v.14 no.1
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• pp.337-345
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• 2014

The visually impaired who have many restrictions on their sight due to impairment of a sense of sight among special senses have substantial difficulties in the areas ranging from very minor behavior in their house to the external activities for social life. Visual impairment may cause many problems in various behaviors for protecting health which have recently drawn a lot of interests. As a method of analysis of collected data, this study conducted the frequency analysis of general characteristics and oral health behavior of the subjects, compared the average of oral public health behavior and oral health condition through t-test and F-test, and conducted the post verification of significant difference among groups with Duncan. For identifying the relevancy between the general characteristics and the oral health behavior, this study conducted Spearman's correlation analysis, and for identifying the impact on subjective, oral health condition, this study conducted multiple regression analysis. SPSS (SPSS20.0 for Windows, SPSS Inc, USA) was used as a statistical program, and the level of significance for determining statistical significance was considered at the level of 0.05. Because the visually impaired are the group whose behaviors for protecting health should be accurately recognized, this study intends to utilize the findings as basic materials for making information communication media suitable for the visually impaired by identifying the real conditions and behaviors of their oral health and analyzing their oral condition caused by such behaviors. With the help of information technology.

• The Journal of the Korea Contents Association
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• v.7 no.8
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• pp.245-254
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• 2007

The purpose of this study is to analyse the effects of salesperson's lifestyle, selling behaviors on strategic management of salesperson. So this study not only examines differences in the salesperson's lifestyle, selling behaviors and job satisfaction but also analyses the impact of salespersons' lifestyle and selling behaviors on job satisfaction. The results of this study are summarized as follows. First, the result of analyzing differences in the lifestyle according to the characteristics of sex, age, academic background income is no significant difference. Second, the result of analyzing differences in the selling behavior according to the characteristics of sex and marriage is significant difference. Third, the result of analyzing differences in the job satisfaction according to the characteristics of store type is significant difference. Salesperson working at the exclusive agencies is most high job satisfaction. According to the result of examining the relationship between salespersons' lifestyle and the selling behaviors, job-oriented lifestyle has positive effects on the customer orientation and hospitality orientation. Finally salespersons' job satisfaction is positively affected by the job-oriented lifestyle and hospitality-orientation selling behavior.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.31 no.5A
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• pp.369-378
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• 2011

In this paper, the response analysis of RC(Reinforced Concrete), SC(Steel-Plate Concrete) containment buildings subjected to a large aircraft impact is performed using Autodyn-3D as Hydrocode. Until now, the impact load in the analysis of aircraft impacts has been applied to target structures at the local area by using the impact load-time history function of Riera. However in this paper, the results of aircraft crash are analyzed by using an aircraft model similar to Boeing 767 and verified by comparing the generated history of the aircraft crash against the rigid target with another history by using the Riera's function. To estimate the resistivity of the impact, the response and safety of SC containment buildings, this study is performed by comparing the four cases of plane concrete, reinforced concrete, bonded containment liner plate at reinforced concrete, and SC structure. Thus, the different behaviors between SC and RC structures when they are subjected to the extreme impact load could be anticipated. Consequently, the improved safety is expected by replacing RC structure with SC structure for nuclear power plants.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.9
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• pp.4349-4358
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• 2013

This study aimed to examine the relation between subjective oral hygiene status of the elderly and oral health impact profile and to present it as basic data for the improvement of quality of life and oral care. The study subjects were 231 elderly people aged 65 and over. This study measured the oral health behavior and subjective oral hygiene status based on cross analysis by calculating the median of OHIP-14 to divide the above-median group into a subgroup and the below-median group into a superordinate group. Correlation and regression analyses were performed to examine the effects on the oral health impact profile. The oral health impact profile according to oral health behaviors was not significant. The oral health impact profile based on the subjective oral hygiene states is currently affected by oral hygiene status, masticatory problems, toothache, xerostomia and halitosis. As a result of regression analysis to confirm the effect on the oral health impact profile, much experience of masticatory problems, toothache, xerostomia and gum diseases is the most influential. This shows that the subjective oral hygiene status is not healthy as the oral health impact profile is high. It is considered necessary to establish an oral health promotion program to improve the quality of life of the elderly and active oral care methods in the future.

• Korean Journal of Social Welfare
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• v.58 no.1
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• pp.5-29
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• 2006

This study analyzed the effect of the teachers' personal variables to the teachers' recognition and attitude about the integrated education. The purpose of this study is to suggest the basic data of the strategic plan for the integrated education of the exceptional children. After survey of the daycare centers' teachers, I analyzed the impact of the individual variables experience, level, education level, experience of integrated education, disabled study - to the teachers' recognitions and behaviors of the integrated education. The results of this study are that personal variables showed different impacts according to the recognition and behaviors. However, integrated education experiences and disabled study experiences showed the important roles. Consequently, I suggest the disabled study and integrated education for the teachers.

• Journal of Korean society of Dental Hygiene
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• v.10 no.4
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• pp.671-681
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• 2010

Objectives : This study was to evaluate the association between perceived oral health and perceived oral symptoms among adults in Daegu. Methods : All 437 subjects aged 18 or more selected convenience sampling were surveyed cross-sectionally via the self-administrated questionnaire. The questionnaire was measured perceived oral symptoms and perceived oral health, and also obtained socio-demographic characteristics, oral health behaviors. To assess the crude associations, bivariate analysis were applied. For the adjusted association between perceived oral health and perceived oral symptoms, multivariate linear regression multiple regression analysis was conducted. Results : 33.2% of the adults rated their perceived oral health was good, and 30.9% as poor. Older age, low education, had peridontal disease was negatively perceived their oral health(p<0.05). As oral symptoms were more frequently perceived, the perceived oral health were negative. Among the factors of perceived oral symptoms, trouble biting/chewing, poor periodontal status, trouble of appearance of teeth were positively associated with the perceived oral health after adjusting for socio-demographic characteristics, oral health behaviors in the regression model. Age, education, income, recent dental treatment, and all perceived oral symptoms showed the highest impact of association with perceived oral health in the baseline-category logit model. Conclusions : Perceived oral health are significantly associated with perceived oral symptoms among adults in Daegu. The findings of this study will be helpful to design plans of oral health promotion in welfare institutions to increase the oral health related quality of life among the adults.

• Korean Journal of Child Studies
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• v.14 no.1
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• pp.153-166
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• 1993

The purpose of the present study was to examine age differences in children's recall for information about aggression, prosociability, and social withdrawal of others and to investigate the impact of likeability on children's recall for social behavioral information. The subjects were 160 children, 20 boys and 20 girls each at 6, 8, 10, and 12 years of age. The subjects listened to descriptions of the social behavior of a hypothetical boy and girl and subsequently reported their recollections. These descriptions were drawn from Bukowski's(1990) stydy, the Pupil Evaluation Inventory, and the Pittsburgh Adjustment Scales. The data were analyzed with 2-way ANOVA, paired T-test, and correlation. Differences across the age levels were found in the number of behaviors correctly recalled for the behavioral descriptions of aggression, prosociability, and social withdrawal. Descriptions of aggressive behavior was recalled more when children listened to a hypothetical boy than to a hypothetical girl. Additional analyses revealed that at 6 years of age, children recalled more descriptions of aggressive and prosocial behavior than of withdrawal and at 10 and 12 years of age, children recalled more descriptions of withdrawal behavior than of aggressive and prosocial behaviors. The more negative the children's affective evaluations of the withdrawal behavior, the better they recalled the withdrawal behavior.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2007.11a
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• pp.37-41
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• 2007

Fast Fourier Transformation(FFT) is one of the most useful way to analyze response signal for the purpose of grasping the dynamic characteristics of system. Excitation is a factor or process making noise or vibration. It's typical and simple experimental method widely used for catching hold of dynamic peculiar characters and modal behaviors of system by frequency analysis. There are harmonic excitation, impact excitation, random excitation, sweep excitation, chirp excitation and so on as the ideal method in an experiment using exciter. In this thesis, excitation testing module for NI-PXI equipment is developed. The analyzing module is developed with LabVIEW tool. A user can generate each waveform for shaking a structure and see quickly and easily modal shape of system with this module. This developed module will be expected to build up more convenient and serviceable measurement system.

• The Journal of Asian Finance, Economics and Business
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• v.5 no.3
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• pp.113-119
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• 2018

Higher Education Institutions (HEIs) are place contributing to the intellectual advancement of the nation, quality human resource, and to a number of socio-economic improvements for society and organizations. Despite facilitators and staffs are the bare-bone of HEIs, there is a scarcity of research, both conceptual and empirical, focusing on their organizational citizenship behaviors (OCB). To attempt to fill this gap, this article develops a conceptual model of OCB under influencing of organizational justice and job satisfaction. The prospective respondents were chosen randomly from HEIs (public and private). Individuals have been employed at least one year and above will be the unit of analysis in which the experimental test of the proposed model will be conducted. The results suggest that organizational citizenship behavior is one of the most important factor influence the organizational performance. Furthermore, the performance of HEIs does not affect only the national human resources, but also impact on national economy. In this context, a conceptual framework is proposed to study the determinants of organizational citizenship behavior in the form of organizational justice and job satisfaction. Additionally, the ultimate benefits of OCB through perceived organizational justice with job satisfaction as mediator is enlightened. Finally, the authors discuss the managerial implications of their research.