• 한국산학기술학회논문지
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• 제17권5호
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• pp.80-85
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• 2016

탄소섬유강화 복합재는 기계적 물성이 우수하여 다양한 산업분야에서 활용되고 있으나 섬유길이가 짧은 단섬유 형태로 함침 되고 있어 강도와 강성을 증대시키는데 한계가 있다. 이를 보완하기 위한 LFT-D성형은 탄소 또는 유리섬유를 열가소성 수지와 혼합하여 압출 후 프레스 성형하여 제품을 만드는 공법으로 연속공정이 가능하고 사출성형에 비해 생산성이 높아 자동차 구조용 부품을 제작하는데 사용할 수 있다. 본 연구에서는 LFT-D공법으로 성형된 탄소 장섬유강화 열가소성 복합소재의 기계적 특성을 파악하기 위하여 탄소 장섬유의 함침과 압출공정을 수행할 수 있는 Lab scale의 소형 압출기 시스템을 제작하였다. Lab scale의 소형 압출기를 사용하여 제작된 탄소 장섬유 복합소재를 프레스 성형하여 시편을 제작하고 재료의 기계적 특성을 평가한 결과, 탄소섬유길이, 프레스 가압압력 및 탄소섬유 함유량이 복합소재의 강도 및 강성의 증가에 영향을 미침을 알 수 있었다. 향후 탄소 장섬유 복합소재의 기계적 성질 향상을 위해서 혼합 스크류 설계, 탄소 섬유코팅 등에 대한 추가적인 연구가 필요하다.

• International Journal of Aeronautical and Space Sciences
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• 제15권2호
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• pp.173-182
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• 2014

The structured singular value (${\mu}$) analysis based method has many advantages for the robust stability analysis of missiles with uncertain parameters. Nevertheless, the present linear fractional transformation (LFT) modeling process, which is the basis of ${\mu}$ analysis, is complex, and not suitable for automatic implementation; on the other hand, ${\mu}$ analysis requires a large amount of computation, which is a burden for large-scale application. A constructive procedure, which is computationally more efficient, and which may lead to a lower order realization than existing algorithms, is proposed for LFT modeling. To reduce the calculation burden, an analysis method is developed, based on skew ${\mu}$. On this basis, calculation of the supremum of ${\mu}$ over a fixed frequency range converts into a single skew ${\mu}$ value calculation. Two algorithms are given, to calculate the upper and lower bounds of skew ${\mu}$, respectively. The validity of the proposed method is verified through robust stability analysis of a missile with real uncertain parameters.

• 대한한방내과학회지
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• 제42권5호
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• pp.777-783
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• 2021

Objective: This case report describes a patient who suffered a drug-induced liver injury and was treated with Saengganggeonbi-tang. Methods: A patient was treated with Korean herbal medicine, and the treatment effect was evaluated using liver function tests (LFT) to determine total cholesterol and triglyceride levels. Results: The patient's LFT levels were normal on 27 July 2021 but became abnormal by 12 August 2021 after taking Western drugs. After 15 days of treatment with Saengganggeonbi-tang, the LFT levels had improved. Conclusion: This study shows that Saenggangeonbi-tang may be an effective treatment for drug-induced liver injury.

• 한국산학기술학회논문지
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• 제16권1호
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• pp.8-14
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• 2015

지금까지 자동차 소재의 경량화 및 연소가스의 저감은 부품의 플라스틱화를 통하여 많은 진전이 있었다. 장섬유 보강 폴리프로필렌 소재가 적용된 프론트 엔드 모듈 캐리어는 플라스틱 구조부품 중에서 가장 성공적인 사례이다. 하지만, 장기 신뢰성 측면에서 볼 때, 자동차용 플라스틱 소재에 대한 피로거동 및 진동내구에 대한 더 많은 연구가 필요한 실정이다. 본 연구에서는 프론트 엔드 모듈 캐리어의 피로설계 및 해석의 기초가 되는 폴리프로필렌 장섬유 소재에 대한 내구성을 분석하였다. 피로수명과 응력진폭 또는 평균응력 간의 상관관계를 평가하기 위하여 다양한 응력비에서 피로실험을 수행하였다. 일정 응력진폭에서 응력비를 변화시킨 결과는 최대하중을 고정시킨 결과보다 피로수명의 변화가 응력비 증가에 따라 2~6% 크게 나타났다. 또한 주사전자 현미경을 통하여 장섬유 보강 폴리프로필렌 소재에 대한 피로균열의 발생, 전파의 파괴기구를 확인하였다.

• 대한한방내과학회지
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• 제34권2호
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• pp.192-203
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• 2013

Objectives : To investigate the incidence of drug-induced liver injury (DILI) by combined-prescription of Korean herbal medicine (KHM; prescribed herbal medicine by doctors of traditional Korean medicine) and Western medicine on liver function. Methods : Sixty-nine in-patients who took KHM and Western medicine for various conditions were enrolled for prospective observational study. All subjects were given liver and renal function tests at the start of hospitalization to establish a baseline. After taking KHM and Western medicine, tests were done at approximately 4-week intervals afterwards. Results : Fifty-three subjects showed normal liver function test (LFT) at baseline, 50 subjects (72.5%) remained within the normal range at the second test, while 3 subjects (4.3%) tests revealed slight increase of LFT. However not a single patient had a high enough raised LFT to indicate liver injury. Sixteen of 69 subjects had abnormal baseline, 11 subjects recovered to normal levels and 5 subjects remained at abnormal level. Among all subjects, there was no statistically significant increase in LFT level between the first and second tests. Conclusions : This study shows that the combined-prescription of KHM and Western medicine did not cause any DILI. In some cases, combined treatment increased LFT levels but those increases were not high enough to have statistical significance. Additional large scale and systematical studies are required for more conclusive proof and results.

• 대한한방내과학회지
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• 제41권3호
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• pp.542-551
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• 2020

Objectives: The purpose of this study was to retrospectively assess the effectiveness of Chunggan plus extract (CGX) in improving liver function in a Korean medical clinic. Methods: We collected the data of inpatients who received CGX to improve abnormal liver function test (LFT) results from March 2016 to February 2020. We analyzed the changes in LFT and adverse events based on subjective symptom changes and creatinine results. Results: The data of eight patients, three male and five female, were selected by inclusion criteria (patients who did LFT before and after the prescription of CGX and who prescribed CGX more than 6 days) and exclusion criteria (patients who administered other herbal medicine for improving liver function except CGX and who are diagnosed with terminal stage of hepatobiliary cancer). As a cause of abnormal LFT, one case was diagnosed with alcoholic liver disease, two cases with non-alcoholic fatty hepatitis, and one case with cholecystitis. Three of the other four were suspected to have drug-induced hepatitis, and one case was determined to have an unknown cause. Most patients showed a decrease in LFT results (Aspartate transaminase 87.5%, Alanine transaminase 87.5%, and Alkaline Phosphatase 100%) without any critical adverse events. Conclusions: CGX may be an efficient and convenient herbal medicine for improving liver function regardless of the chief impression. Further study should be conducted to evaluate the effectiveness of CGX.

• Korean Journal of Acupuncture
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• 제38권4호
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• pp.275-281
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• 2021

Objectives : This study reports changes in liver function test (LFT) after Korean Medicine treatment in patients admitted to Korean Medicine hospital with abnormal LFT. The purpose of this study is to investigate the relationship between the Korean medicine treatment and abonormal LFT to verify safety of Korean medicine treatment by analyzing index of LFT. Methods : From Oct. 2015 to Sep. 2020, the result was analyzed for 91 patients admitted to the Pohang Korean Medicine Hospital and received Korean Medicine treatment. Asparate aminotransferase (AST), alanine aminotransferase (ALT) and total bilirubin (TB) were compared at admission and discharge. Results : Comparison between admission and discharge LFT showend AST decreased from 52.72±25.08 to 43.2±19.20, ALT from 70.85±32.40 to 62.13±29.40, and TB from 1.33±0.37 to 0.81±0.29. Conclusions : After Korean medicine treatment, AST, ALT, and TB decreased compared with the values at admission. Further studies on safety of Korean Medicine treatment are warranted.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2004년도 춘계학술대회 논문집
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• pp.1180-1187
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• 2004

Relative displacements between decks should be within the allowable limit under horizontal forces in high-speed railway bridges. Longitudinal force transmitters(LFT) have been introduced ih high-speed railway bridges for test track. The horizontal forces on the pier supporting the fixed bearing are transmitted to the near piers supporting the sliding bearings by LFT, The performance of LFT was investigated by field test in which the braking and acceleration tests using KTX were conducted in Baebang viaduct. The relative displacements between decks were measured infield test and were compared with the numerical results and the allowable limit.

• 대한한방내과학회지
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• 제30권1호
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• pp.241-248
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• 2009

Object : Liver cirrhosis is a disease of the liver in which normal cells are replaced by scar tissue. The purpose of this case is to report the improvement of liver cirrhosis after herb-med, acupuncture & moxibustion complex therapy. Methods : We provided herb-med, acupuncture & moxibustion complex therapy to a patient who suffered from ascites and fatigue. We examined LFT & Child-Pugh class to evaluate the effectiveness of oriental treatment. Result and Conclusion : We observed that herb-mod. acupuncture & moxibustion complex therapy decreased symptoms of liver cirrhosis and improved general condition of a patient who suffered from ascites and fatigue. In the LFT result, Child-Pugh class was improved.

• Journal of Acupuncture Research
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• 제25권6호
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• pp.47-54
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• 2008

Objectives : This study was aimed to figure out how effectively acupuncture treatment and herb-medicine work on patients with elevation of LFT value and lipid-obesity index. Methods : The subject were 23 patients visited to Dept. of Acupuncture and Moxibustion, Kwangdong Oriental Medicine Hospital, who complained chronic fatigue and wandering pain from Oct. 2007. to Oct. 2008. Before treatments, they were tested for LFT, total cholesterol, triglyceride, body fat ratio and obesity index. They were treated with Ganjeonggyeok acupuncture weekly for 1 month. During acupuncture treatments, we applied Sangkankunbi-tang to all patients twice a day. After 1 month, they were retested for LFT, total cholesterol, triglyceride, body fat ratio and obesity index. Results : 1. After treatments, we could get the result of dropping means of AST, ALT and $\gamma$-GTP value. Statistical significance of ALT and $\gamma$-GTP were recognized before and after treatments, but AST was not recognized. 2. After treatments, we also could get the result of dropping means of total cholesterol, triglyceride, body fat ratio and obesity index. Statistical significance of all values were recognized before and after treatments. 3. Among 23 patients, 10 cases were reported that they were not within normal limits at least one in AST, ALT and $\gamma$-GTP. After treatments of those patients, we could get the result of dropping means of AST, ALT and $\gamma$-GTP value. Statistical significance of all values were recognized before and after treatments. 4. Among 23 patients, 19 cases were reported that they were not within normal limits at least one in total cholesterol, triglyceride, body fat ratio and obesity index. After treatments of those patients, we could get the result of dropping means of total cholesterol, triglyceride, body fat ratio and obesity index. Statistical significance of all values were recognized before and after treatments. Conclusions : Though further study is necessary, our finding suggest that the conduction of Ganjeonggyeok acupuncture and Sangkankunbi-tang treatments have helped to decrease the figures of LFT and lipid-obesity index in patients.