• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.45 no.3
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• pp.217-225
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• 2017

This research represents comparison and validation of static aerodynamic results in different wind tunnel organizations and EFD-CFD results. KAFA conducted wind tunnel tests with Standard Dynamics Model(SDM) which is based on the NRC model, the same configuration of KARI; and then compared and analyzed similarities and differences of the data from KARI and NRC results for verifying the accuracy of wind tunnel tests. Also, We compared the result of CFD with that of wind tunnel tests and examined strakes effect in static characteristics which are attached on the forward fuselage of SDM for investigating the cause of some discrepancies. From this analysis, there are some discrepancies in Cm tendency between EFD-CFD and it did not show the big difference of aerodynamic characteristics by strake effects. Thus, we need to research additionally for analyzing the different cause of some discrepancies such as vortex structures by the rear strut or intake of SDM and regenerating grid resolution of CFD.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.15 no.5
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• pp.203-220
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• 2020

The purpose of this study is to examine the importance of entrepreneurs' well-being, and to propose several ways to improve it. First, the factors influencing entrepreneurs' well-being were explored via previous literature review, and positive psychological capital based on positive psychology was selected as the main factor. In addition, the hypotheses were formulated and the research model was constructed by selecting authentic leadership, mastery goal orientation, and social support as the antecedents predictably associated with positive psychological capital. To empirically analyze the proposed model, a questionnaire survey was conducted for the entrepreneurs who fulfilled the training/coaching/consulting programs offered by the Youth Startup Academy. By using the collected 133 responses, PLS-Structural Equation Analysis, PLS-Multi Group Analysis(MGA), and PLS-Importance-Performance Map Analysis(IPMA) were performed. As a result, it was found that positive psychological capital had a high causal relationship with the well-being of entrepreneurs; and authentic leadership and mastery goal orientation had a positive effect on positive psychological capital. However, the statistical significance of the impact of social support has not been verified. While differences in causality between early and growing stages of start-ups only acted as sub-factors of positive psychological capital, the aforementioned three antecedents showed a significant difference for hope and optimism, respectively. This study expanded the topic of entrepreneurship-related research, which mostly focuses on identifying the performance factors of start-ups. It is meaningful in that it empirically verified the causality model constructed by exploring the factors with respect to the mental well-being of entrepreneurs, which is a main theme in the entrepreneurship-related research. These results found in the current study will render practical insights to entrepreneurs, researchers, and educators.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.12
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• pp.164-172
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• 2017

This study was conducted to compare physical fitness, self-esteem, organizational commitment and transformational leadership among non-smoker and smoker ROTC cadets. This study used 425 questionnaires from male grade 3 and 4 ROTC cadets of 12 universities located in P city and G-do. Data were collected from May 1 to June 23, 2017. The data were analyzed by SPSS/WIN 23.0 using a ${\chi}^2-test$, independent t-test, and Pearson's correlation coefficient. Running 3km (t=3.26, p=0.046), self-esteem (t=1.06, p=0.003), organizational commitment (t=2.57, p<0.001) and transformational leadership (t=3.98, p<0.001) were significantly lower in the smoking group than the non-smoking group. There was a positive correlation between self-esteem, organizational commitment, and transformational leadership in both non-smokers and smokers. Therefore, to practice smoking cessation for the health promotion of ROTC cadets smokers, it is necessary to develop an effective education and intervention program that can enhance self-esteem, organizational commitment and transformational leadership.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.6
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• pp.2677-2687
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• 2013

Entrepreneurship of a founder and psychological characteristics are very important factors for the start-up success. To understand the importance like this, this study investigated effect relationships of the entrepreneurship and psychological characteristics on the start-up success. For this, 122 copies of the questionnaire were empirically analyzed for the youth entrepreneurs who entered the youth founder academy which is founded and managed by the Small and Medium Business Corporation. According to results of analysis, both the entrepreneurship consisting of proactivenss, risk taking and autonomy, and the internal locus of control, the psychological characteristics were found to have positive effects on the start-up success. Therefore, this study suggested theoretical and practical implications, as below, according to the results. Firstly, we must be aware of the importance of the entrepreneurship from the perspective of a successful establishment, and, prospective entrepreneurs, who are planning to the start-up, have to judge their entrepreneurship and, only then, make a decision. Secondly, we have to put our best efforts into developing more effective education on start-up, which deals with improving youth founder's entrepreneurship. Therefore, education institutions for start-up are needed in order to develop educational programs such as "Entrepreneurship Training Programs". Thirdly, we must recognize that the role of family is important because most entrepreneurship and psychological characteristics are formed in a person's childhood. Forth, the entrepreneur, themselves, must realize that they has to make an effort to improve their entrepreneurship. Lastly, youth founder's internal locus of control has to be enhanced. Thus, greater attention is required from both the entrepreneur themselves, and educational institutions for start-up.

• Journal of the Korean Wood Science and Technology
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• v.36 no.4
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• pp.11-18
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• 2008

Anatomical characteristics of volumetric composition, fiber length, vessel diameter, and crystalline properties of cellulose in kenaf (Hibiscus cannabinus L.) planted in the reclaimed land of Buan-si, Korea were examined to understand the growth characteristics using a light microscopy and an X-ray diffraction method. The samples of kenaf were taken from six positions (3 cm, 35 cm, 70 cm, 105 cm, 280 cm, and 320 cm) of each stem over the growth period (July, August, September, and October) after seeding in the mid-May. In the kenaf stem, phloem constituted 10 to 15 %, xylem 66 to 82%, and pith 7 to 19%. The ray, bast fiber, and remainder comprised 50%, 20%, and 30% of the phloem, respectively. The volume of vessel, ray, and fiber in the xylem was approximately 10, 15, and 75%, respectively. The proportion of cell wall was 30.92% at the base of stem and 46.40% at the top of stem, respectively. The average length of bast fiber and xylem fiber was about 2.8 mm and 0.9 mm, respectively. Radial and tangential diameters of vessel increased with the increase of growth period, while they decreased with increasing the stem height. Relative crystallinity ranged from 70 to 79% in phloem and from 50 to 56% in xylem. Cellulose crystallite width was about 3 nm both in the phloem and xylem. Thus, the volumetric composition and cell dimensions in the phloem and xylem appeared to be varied with the growth period and the stem height.

• Journal of the Korean Wood Science and Technology
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• v.35 no.6
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• pp.43-49
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• 2007

Anatomical properties of Kenaf (Hibiscus cannabinus L.) planted in a reclaimed-land of Korea were examined to understand the growth characteristics by an optical and scanning electron microscopy. The samples of kenaf were taken from four positions of the stem (3, 35, 70, 105 cm above from the ground) in four growth periods (July. August, September, October) from seeding planted in the middle of May. Bast fiber, phloem rays, cortex parenchyma cells and sieve tube members were observed in phloem, and vessel elements, fibers and rays in xylem. Solitary and multiple radial pores existed in xylem. The cell types of ray parenchyma in radial section were procumbent, upright, and square. The intervascular pitting showed an alternate type. Xylem proportion, the number of bast fibers and dimension of phloem rays increased with increasing growth period, and decreased with increasing stem height. The proportion of multiseriate rays was higher than that of uniseriate and biseriate rays in xylem with increasing growth period. On the other hand, The proportion of multiseriate rays was lower than that of uniseriate and biseriate rays in xylem with increasing stem height.

• Korean Journal of Plant Resources
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• v.8 no.3
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• pp.237-246
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• 1995

In this study, the callus was induced and regenerated from the immature embryo and ultrastructural characteristics of developmental stages in Citrus junos SIEB, were investigated. The yellowish callus was induced by 5 to 6 week of culture of citrus. In proliferation callus after 6 weeks of culture, large vacuole was formed by fusion between adjacent small ones. In the non-embryogenic callus cultured for 12weeks, re-differentiated cells of callus showed the large nucleus with globular nucleus and amyloplast with large size of starches. In the embryogenic callus cltured for 14-16 weeks, the active exocytosis occurred in cells, secretory vesicles appeared on cell membrane and small particles from cytoplasm were released to intercelluar space. In the embryogenic callus cultured for 24 weeks, a sperical type of chloroplast bounded on cytoplasm by double membrane and typical grana was dispersed equally among matrix. In the normal plantlet after 26 weeks of culture, a lot of vessels and companion cells apperaed in the leaf cell of plantlet. In the normal plantlet after 30 weeks of culture, the immature leaf showed many small companion cells, sieve tubes and central vacuole. Also, the secondary vacuole protruded into the central vacuole and elongated chloroplasts near plasma membrane. In the matured plant habituated on the soil, palisada tissue composed of orderly arranged cells contained the nucleus in the center of the cell and large vacuoles on either side of the nucleus.

• Journal of Acupuncture Research
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• v.27 no.1
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• pp.129-135
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• 2010

Objectives : The purpose of this research was to examine that effect of Sosang($LU_1$)-Eunbaek($SP_1$) bloodletting was similar to effect of Sa-kwan $LI_4$) and Taechung($LR_3$)> acupuncture on pain and discomfort of acute dyspepsia in upper abdomen. Methods : We divided 36 patients with acute dyspepsia into two groups and treated Group A with Sosang($LU_{11}$)-Eunbaek($SP_1$) bloodletting and Group B with Sa-kwan $LI_4$) and Taechung($LR_3$)> acupuncture. Pain and discomfort in upper abdomen was measured by Visual Analogue Scale(VAS) scores of the two groups before treatment and after 15 minutes to treat. Results : Both group A and B represented effective improvement in VAS of pain and discomfort in upper abdomen. And there was no difference between A group and B group statistically. Conclusions : It is suggested that Sosang($LU_{11}$)-Eunbaek($SP_1$) bloodletting may have similar effect compared with Sa-kwan $LI_4$) and Taechung($LR_3$)> acupuncture on acute dyspepsia treatment.

• Clinics in Shoulder and Elbow
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• v.12 no.2
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• pp.126-136
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• 2009

Purpose: We evaluated the correlation of the anatomic parameters of the acromion those represent on the magnetic resonance image (MRI) of impingement syndrome. Materials and Methods: From June, 2004 to December, 2005, 71 cases were surgically proven to be impingement syndrome, and the anterior acromial hooking angle, the lateral acromial hooking angle (AAHA and LAHA) and the acromial hooking index (AHI: the sum of the AAHA and LAHA) were compared to 16 control cases. At the same period, 55 cases were surgically proven to be partial or full thickness rotator cuff tear, and age, gender and twelve anatomic parameters, including the acromial type, the acromial angle, the anterior covering, the acromial slope, the AAHA, the lateral acromial angle, the acromial torsional angle, the lateral acromial angulation, the LAHA, the lateral covering, the acromiohumeral distance and the AHI were assessed. Results: The AAHA and AHI were increased as impingement syndrome proceeded. The acromial type and acromial angle, and the AAHA, LAHA and AHI showed significant differences between the controls and the rotator cuff tear patients on univariant analysis. On multivariant analysis, gender was most strongly correlated with rotator cuff tear. Age, AAHA and the acromial angle showed similar correlation, respectively. Conclusion: The coronal acromial shape is correlated with rotator cuff tear, and it is important to correct the lateral acromial shape when performing acromioplasty.

• Journal of Navigation and Port Research
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• v.42 no.1
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• pp.31-38
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• 2018

The purpose of this study is to contribute to the study of the prevention of diseases and promotion of health of ocean going vessel crew members, through the medical diagnosis and disease classification efforts of this study. From the second half of 2016 to 2017, the diagnosis and health characteristics of 195 crew members were collected through counseling, treatment, and emergency care for about 1 year and 2 months. As a result, it is noted that the incidence of diseases was in the order of urticaria (5.6%), lumbar sprain (4.1%), acute gastroenteritis (3.1%) and anxiety (3.1%). In categorical review, the incidence of musculo-skeletal disease was the most common (25.1%) which was followed by skin disease (17.9%) and digestive disease (11.3%). In addition, the disease that was noted as was the most common in the under 30 years old category, and the incidence of the disease was high in the crew group. Finally, there was a difference between the pathogenesis (trauma vs disease, etc.) (p <.001) and the type of vessel (merchant ship and fishing vessel) (p <.005) as noted in this case.