진정, 무엇을 선택할 것인가?

강동훈 책갈피 2012 마르크스21 Vol.- No.13

Poly(glycolic acid)/Hydroxyapatite Scaffolds Fabricated by 3D Printing Technique for Bone Regeneration

강동훈,권오형,이효림,고윤제 한국고분자학회 2021 한국고분자학회 학술대회 연구논문 초록집 Vol.46 No.2

Hydroxyapatite (HAp) is a material mainly used for bone graft component. However, sintered HAp has poor mechanical properties and difficulty for cell adhesion and proliferation with irregular pore structures. Porous 3D scaffolds for bone tissue regeneration were fabricated by mixing poly(glycolic acid) (PGA) and HAp with 3D printing technique. This technique can induce improved bone conduction ability with similar mechanical strength. Through the cell proliferation test, PGA/HAp scaffolds with a 400 μm pore size were accepted. PGA scaffolds containing 12.5 wt% HAp showed significant compressive strength, osteogenesis, mineralization and biodegradation. In in vivo animal test using rabbit bone defect model, the PGA/HAp scaffolds exhibited 47% bone regeneration, with superior bone mineral density 8 weeks after surgery. 3D-printed PGA/HAp scaffolds could provide a possible option to promote patient-customized bone regeneration.

Fabrication of Poly(glycolic acid)/Hydroxyapatie Scaffolds by 3D Printing for Hard Tissue Regeneration

강동훈,이효림,고윤제,권오형 한국고분자학회 2022 한국고분자학회 학술대회 연구논문 초록집 Vol.47 No.1

Numerical Study About Buffet Characteristics and Attenuation of Vertical Tail at High Angles of Attack

강동훈,권오준 한국항공우주학회 2020 International Journal of Aeronautical and Space Sc Vol.21 No.2

In the present study, detached eddy simulations were conducted to investigate buffet characteristics of the vertical tail. Unsteady flow phenomena were observed to clarify the cause of buffet onset. The location of vortex breakdown was also predicted. Simulations were carried out for high-angle conditions of more than buffet onset. Finally, to attenuate buffet intensity, two design parameters involving the spanwise translation and the tilt angle of the vertical tail were considered. It was found that the wake-like vortex structure developed after the event of vortex breakdown was the main cause of buffet onset. It was also found that the location of vortex breakdown moves upstream with increase in an angle of attack, which accelerates dissipation of the vortex core near the vertical tail. Peak-to-peak excitation phenomenon was featured as buffet characteristics acting on the vertical tail. It was demonstrated that the factor to more excite buffet was vortex shedding originated from the trailing edge of the wing at the highest angle, in which the peak level was the largest. The most discernible effect of buffet attenuation was observed when two parameters were simultaneously applied, which are suggested as a design application under the development of aircrafts.

방한 싱가포르 관광객의 패키지 여행상품 불만족 내용분석

강동훈,박재영,이재섭 관광경영학회 2019 관광경영연구 Vol.91 No.-

The purpose of the study is to investigate the dissatisfaction factors of package tour products and to provide better information to develop package tour products using content analysis method by analyzing tourists’ actual reviews. Content analysis is often used for analyzing the meaning of text in the fields of tourism. Singapore tourists’ customer feedback were analyzed after they traveled Korea through Singapore E Travel agency. The qualitative data was collected from March 2018 to March 2019. A total of 242 responses were obtained from a total of 47 tour groups, and content analysis was used to figure out dissatisfaction factors of package tour products. The result of this research found six factors: schedule related item, transportation related item, shopping related item, meal related item, accommodation related item, and tour guide related item. The results of this study can provide practical implications to inbound travel agent. The article concluded with limitations and suggestions for the future research.

소셜미디어 품질이 관광지 이미지와 행동의도에 미치는 영향 - 20대 대학생을 중심으로 -

강동훈,정태연 한국호텔리조트학회 2022 호텔리조트연구 Vol.21 No.5

In this study, the effect of social media quality on the destination image and the relationship between the image of the destination image and behavioral intention were studied. An online survey was conducted with university students in their 20s who had experience using social media such as Instagram and YouTube of Jeonju City. The results of the study are as follows. First, it was found that information quality and emotional quality factors of social media quality had a significant effect on the cognitive image, so Hypothesis 1-1 was partially adopted. Second, the information quality and emotional quality factors of social media quality were found to have a statistically significant effect on the emotional image, so Hypothesis 1-2 has been partially adopted. Third, it was found that the cognitive and emotional factors of the destination image had a statistically significant effect on the intention to visit, so Hypothesis 2-1 was accepted. Finally, it was found that the cognitive and emotional factors of the destination image had a statistically significant effect on e-wom intention, so Hypothesis 2-2 Adopted. This study proves the necessity of utilizing social media as online marketing strategies to improve destination image.

동측 이하선의 진행성 위축을 동반한 일측 악하선 결손 1예

강동훈,안동빈,김재혁,손진호 대한이비인후과학회 2013 대한이비인후과학회지 두경부외과학 Vol.56 No.6

The isolated unilateral aplasia of the submandibular gland (SMG) is an extremely rare condition, because most cases of congenital absence of the major salivary glands are associated with other anomalies and several major salivary glands. Worldwide, only 15 cases of isolated unilateral SMG aplasia have been reported. Here, we report a case of a 35-year-old woman with isolated unilateral SMG absence. The ipsilateral parotid gland was hypertrophied at the time of initial diagnosis, but this gland showed significant atrophy during the subsequent 3-year follow-up. This phenomenon may be associated with ipsilateral SMG aplasia, and we report this unique case along with a literature review in this paper.

Effects of feeding high-energy diet on growth performance, blood parameters, and carcass traits in Hanwoo steers

강동훈,Chung Ki-Yong,박보혜,김의형,Jang Sun Sik,Smith Zachary K,Kim Jongkyoo 아세아·태평양축산학회 2022 Animal Bioscience Vol.35 No.10

Objective: Our study aimed to investigate the effects of a 2% increase in dietary total digestible nutrients (TDN) value during the growing (7 to 12 mo of age) and fattening (13 to 30 mo of age) period of Hanwoo steers. Methods: Two hundred and twenty Hanwoo steers were assigned to one of two treatments: i) a control group (basal TDN, BTDN, n = 111 steers, growing = 70.5%, early fattening = 71.0%, late fattening = 74.0%) or high TDN (HTDN, n = 109 steers, growing = 72.6%, early = 73.1%, late = 76.2%). Growth performance, carcass traits, blood parameters, and gene expression of longissimus dorsi (LD) (7, 18, and 30 mo) were quantified. Results: Steers on the BTDN diets had increased (p≤0.02) DMI throughout the feeding trial compared to HTDN, but gain did not differ appreciably. A greater proportion of cattle in HTDN received Korean quality grade 1 (82%) or greater compared to BTDN (77%), while HTDN had a greater yield grade (29%) than BTDN (20%). Redness (a*) of LD muscle was improved (p = 0.021) in steers fed HTDN. Feeding the HTDN diet did not alter blood parameters. Steers fed HTDN diet increased (p = 0.015) the proportion of stearic acid and tended to alter linoleic acid. Overall, saturated, unsaturated, monounsaturated, and polyunsaturated fatty acids of LD muscle were not impacted by the HTDN treatment. A treatment by age interaction was noted for mRNA expression of myosin heavy chain (MHC) IIA, IIX, and stearoyl CoA desaturase (SCD) (p≤0.026). No treatment effect was detected on gene expression from LD muscle biopsies at 7, 18, and 30 mo of age; however, an age effect was detected for all variables measured (p≤0.001). Conclusion: Our results indicated that feeding HTDN diet could improve overall quality grade while minimum effects were noted in gene expression, blood parameters, and growing performance. Cattle performance prediction in the feedlot is a critical decisionmaking tool for optimal planning of cattle fattening and these data provide both benchmark physiological parameters and growth performance measures for Hanwoo cattle feeding enterprises. Objective: Our study aimed to investigate the effects of a 2% increase in dietary total digestible nutrients (TDN) value during the growing (7 to 12 mo of age) and fattening (13 to 30 mo of age) period of Hanwoo steers.Methods: Two hundred and twenty Hanwoo steers were assigned to one of two treatments: i) a control group (basal TDN, BTDN, n = 111 steers, growing = 70.5%, early fattening = 71.0%, late fattening = 74.0%) or high TDN (HTDN, n = 109 steers, growing = 72.6%, early = 73.1%, late = 76.2%). Growth performance, carcass traits, blood parameters, and gene expression of longissimus dorsi (LD) (7, 18, and 30 mo) were quantified.Results: Steers on the BTDN diets had increased (p≤0.02) DMI throughout the feeding trial compared to HTDN, but gain did not differ appreciably. A greater proportion of cattle in HTDN received Korean quality grade 1 (82%) or greater compared to BTDN (77%), while HTDN had a greater yield grade (29%) than BTDN (20%). Redness (a*) of LD muscle was improved (p = 0.021) in steers fed HTDN. Feeding the HTDN diet did not alter blood parameters. Steers fed HTDN diet increased (p = 0.015) the proportion of stearic acid and tended to alter linoleic acid. Overall, saturated, unsaturated, monounsaturated, and polyunsaturated fatty acids of LD muscle were not impacted by the HTDN treatment. A treatment by age interaction was noted for mRNA expression of myosin heavy chain (MHC) IIA, IIX, and stearoyl CoA desaturase (SCD) (p≤0.026). No treatment effect was detected on gene expression from LD muscle biopsies at 7, 18, and 30 mo of age; however, an age effect was detected for all variables measured (p≤0.001).Conclusion: Our results indicated that feeding HTDN diet could improve overall quality grade while minimum effects were noted in gene expression, blood parameters, and growing performance. Cattle performance prediction in the feedlot is a critical decisionmaking tool for optimal planning of cattle fattening and these data provide both benchmark physiological parameters and growth performance measures for Hanwoo cattle feeding enterprises.

고상법을 활용한 리튬이차전지 폐양극활물질 재활용 기술 연구

강동훈,임주원,고민성 한국표면공학회 2023 한국표면공학회지 Vol.56 No.4

As the demand for lithium-ion batteries, a key power source in electric vehicles and energy storage systems, continues to increase for achieving global carbon neutrality, there is a growing concern about the environmental impact of disposing of spent batteries. Extensive research is underway to develop efficient recycling methods. While hydrometallurgy and pyrometallurgy methods are commonly used to recover valuable metals from spent cathode materials, they have drawbacks including hazardous waste and complex processes. Hence, alternative recycling methods that are environmentally friendly are being explored. However, recycling spent cathode materials still remains complex and energy-intensive. This study focuses on a novel approach called solid-state synthesis, which aims at regenerating the performance of spent cathode materials. The method offers a simpler process and reduces energy consumption. Optimal heat treatment conditions were identified based on experimental results, contributing to the development of sustainable recycling technologies for lithium-ion batteries.

격자 불일치 이종접합 에피탁시의 문제를 극복할 수 있는 Compliant Substrate에 관한 연구

강동훈,황성민,김용,김은규,최인훈 한국진공학회 1999 한국진공학회 학술발표회초록집 Vol.- No.-