• 유변학
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• 제10권4호
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• pp.227-233
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• 1998

잠재성 경화제인 N-benzylpyrazinium hexafluoroantimonate(BPH)를 Cycloaliphatic계 에폭시 (CAE)/DGEBA계 에폭시의 혼합물에 1 mol% 첨가 시킨 후 혼합 조성비에 따른 유변학적 특성과 경화 동력학에 대해 연구하였다. 잠재특성은 등온 DSC를 이용하여 각각 $150^{\circ}C$와 $50^{\circ}C$의 반응 온도에 대한시간의 함수로서 전화량을 구하여 측정하였다. 블렌드 시스템의 유변학적 특성은 레오미터를 사용한 등온 실험을 통하여 storage modulus (G'), loss modulus (G") 그리고 damping factor (tan$\delta$)를 구한 후 이들 데이터로부터 겔화 시간을 측정하였다. 겔화 시간과 경화 온도를 Arrenius equation에 적용시킨 결과 가교 활성화 에너지 ($E_c$)를 구할 수 있었으며 겔화 시간과 활성화 에너지 모두 DGEBA의 함량이 증가할수록 증가하였다. 경화 활성화 에너지 ($E_a$)를 동적 DSC를 이용하여 Kissinger method에 의해 구하였는데 활성화 에너지는 CAE의 함량이 증가할수록 감소함으로써 높은 반응성을 나타내었는데, 이는 짧은 반복 단위와 단순한 곁사슬기 그리고 반응 매질 내의 점도 등에 기인한다.기인한다.

• Macromolecular Research
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• 제12권3호
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• pp.282-289
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• 2004

We have extensively characterized the fluorescence behavior of unsaturated polyester (UP) resin in the absence and presence of a 1,3-bis-(l-pyrenyl)propane (BPP) fluorescent probe at various dynamic and isothermal cure histories by means of a steady-state fluorescence technique using a front-face illumination equipment. In addition, we explored the effect of the fluorescence intensity on the relaxation of the fluorescent probe in the UP resin by resting the dynamically and isothermally cured resin at ambient temperature and pressure for 24 h. The monomer fluorescence intensity, which has two characteristic peaks at 376 and 396nm, changed noticeably depending on the cure temperature and time and provided important information with respect to the molecular and photophysical responses upon curing. The result of the fluorescence study indicates that the increased local viscosity and restricted molecular mobility of the UP resin surrounding the BPP probe after curing are both responsible for the enhancement of the monomer fluorescence intensity. Our results also demonstrate that once the BPP probe has enough time to rearrange and become isolated prior to fluorescence, a sufficient amount of fluorescence is emitted. Therefore, we note that the fluorescence behavior of this UP resin system is influenced strongly by the relaxation process of the fluorescent probe in the resin as well as process used to cure the resin.

• 한국임상약학회지
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• 제27권2호
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• pp.77-82
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• 2017

Background: Clostridium difficile associated diarrhea (CDAD) is a leading cause of hospital-associated gastrointestinal illness. Risk factors for CDAD include advanced age, long-term admission, antibiotics, proton-pump inhibitor or $H_2$ blocker use and immunosuppression. The practice guideline of American Journal of Gastroenterology (2013) suggests metronidazole for the first-line therapy of mild-moderate CDAD as well as vancomycin for severe CDAD. MICU inpatients receiving stress ulcer prophylaxis and antibiotics are susceptible to nosocomial CDAD. Therefore, this study aimed to evaluate occurrence and treatment of CDAD in MICU. Methods: Patients who were admitted to the MICU and had CDAD from August 2012 to August 2015 were analyzed retrospectively. Results: Of the 90 patients with CDAD, 20 patients (2.22%) had mild-moderate CDAD (16 received metronidazole and 4 received vancomycin therapy) and 70 patients (77.8%) had severe CDAD(54 received metronidazole and 16 received vancomycin therapy). Among the patients with mild- moderate CDAD, treatment with metronidazole or vancomycin resulted in same clinical cure in 50% of the patients (p=1.00). Among the patients with severe CDAD, treatment with metronidazole or vancomycin resulted in clinical cure in 40.7% and 50.0% of the patients, respectively (p=0.511). Clinical symptoms recurred in 7.4% of the severe CDAD patients treated with metronidazole and 6.3% of those treated with vancomycin(p=0.875). Conclusion: Our findings suggest that metronidazole and vancomycin are equally effective for the treatment of mild-moderate CDAD; however, vancomycin demonstrated higher clinical cure rate and lower recurrence rate for severe CDAD, although the difference was not statistically significant. For better clinical outcomes, appropriate medication use by disease severity is needed.

• Composites Research
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• 제17권5호
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• pp.47-53
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• 2004

본 연구에서는 열잠재성 양이온 촉매인 N-benzylpyrazinium hexafluoroantimonate (BPH)와 benryl-2,5-dimethylpyrazinium hexafluoroantimonate (BDPH)를 합성하였고, 이관능성 에폭시 수지(diglycidylether of bisphenol A, DGEBA)에 개시제로 1 wt.%의 촉매를 혼합하여 DSC, NIR TGA 그리고 DMA를 이용하여 경화거동과 열안정성을 알아보았다. 촉매의 잠재특성은 $100∼180^{\circ}$의 반응 온도에 따른 전환율을 near-IR로부터 조사하였다. NIR 분석으로부터, BPH에 의한 에폭시 수지의 전환율은 BDPH와 비교하여 높은 전환율을 나타내는 것을 확인할 수 있었다. 그리고 TGA 분석 결과, 초기 열분해 온도(IDT)와 적분 열분해 온도(IPDT)에 입각하여 DGEBA/BDPH 시스템의 열안정성이 DGEBA/BPH 시스템보다 상대적으로 낮은 값을 나타냈다. 이는 BDPH 구조의 입체 장애로 인해 BPH보다 열안정성 인자이 더 낮게 측정된 것으로 판단된다.

• 대한한의학회지
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• 제17권2호
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• pp.17-33
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• 1996

Chinese medical science with long history has experience and theory of cure and prevention as well as the perfect different system with western medicine. Western medical science also was introduced in recent times and has been used in fast development in China extensively. Therefore only China that coexist oriental and western medicine is used the term, the integration of oriental and western medicine. Its object is to make better treatment and prevention value with utilizing their strong point and weak point. That is, its great principle is to develop through interchange together without interference in the other science. For mutual growth of both medical science, national concern and support, medical staffs, administrative system and a lot of fruits, etc should be arranged simultaneously. This paper was obtained the as follows. 1. The system of public health administration is composed a sanitary department for a western medicine and a managing agency for a chinese one in the center. There are each local organization under the control both agency in the locality 2. The importance of the integration of chinese and western medicine is to get the merit of special chinese system through the interchange of both medicine and union with modem science and chinese pharmacy. 3. It is the long term and great project. So its important study field is illness treatment and cure, oriental medical remedy and theory, acupuncture and moxibution etc. 4. It makes steady progress in all the healthy medical field. It has studied its foundation, the education of medical staffs, scientific study and strengthening of skill management considerably. 5. The products are the development of new chinese medicines and many researches about traditional chinese medical science. In brief, the integration of chinese and western medical science is the historical stream. Besides it will contribute toward the cure and prevention of human illness for future 21 century.

• 공업화학
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• 제7권2호
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• pp.356-361
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• 1996

반응성 첨가제로 HQ와 PGE를 합성시킨 HQ-PGE를 사용하여, DGEBA/MDA계의 경화반응이 일어날 때의 속도론을 DSC와 FT-IR을 이용하여 조사하였다. 그리고, Kissinger equation과 Arrhenius equation을 이용하여 활성화 에너지와 pre-exponential factor 값을 구하였다. 계의 활성화 에너지는 HQ-PGE가 첨가되었을 때 감소하였다. 합성 HQ-PGE가 5 phr 첨가되었을 때, DGEBA/MDA계의 활성화 에너지는 FT-IR로 측정하였을 때 7.8 kcal/mol, DSC로 측정하였을 때에 11.3 kcal/mol을 나타내었다. 이 값은 HQ-PGE가 첨가되지 않은 경우보다 각각 30%, 9% 감소된 값이었다. 이 결과들을 통해서 반응성 첨가제로 사용된 HQ-PGE는 본 계에서 촉매의 역할을 함을 알 수 있었다.

• 한국산학기술학회논문지
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• 제9권3호
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• pp.734-741
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• 2008

현대인들은 보다 더 질 좋은 삶을 영위하기 위한 노력들이 많이 이루어지고 있다. 특히 운동을 통해서 질병의 예방뿐만이 아니라 치료를 요하는 당뇨병 환자, 노약자, 병원에서 퇴원하여 자택에서 요양하는 환자들이 운동 처방에 따라 운동 치료를 한다. 본 논문에서는 지그비 기반의 유비쿼터스 케어 시스템을 개발하였다. 이 시스템은 운동처방을 받아 체계적으로 운동할 때 발생하는 운동 이력 정보를 누적 관리하여 질병의 예방하도록 지원한다. 이 시스템은 자신의 운동 이력 및 건강 정보를 웹페이지를 통하여 확인할 수 있을 뿐만 아니라, 휴대폰을 이용하여 환자들에게 운동 처방에 관한 내용을 통보하여 준다.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2008년도 춘계학술대회논문집
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• pp.747-752
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• 2008

Fiber-guided sensor system using a generator and a receiver can detect the amplitude of load or pressure. However, this type of sensor can show some difficulties in detecting the location of damages and pressure loadings. To overcome this weakness of this type, the ultrasonic active fiber sensor, which has an integrated ultrasonic generator and sensing part, was developed in this study. By using this sensor system, the location of mechanical loads can be exactly detected. Moreover, the ultrasonic active fiber sensor is more cost-effective than an ultrasonic fiber sensor using two piezoelectric transducers which are used as a generator and a receiver, respectively. Two applications of the ultrasonic active fiber sensor are demonstrated: cure monitoring of lead and measurement of liquid level. Present results showed that the active fiber sensor can be applied for various environmental sensing.

• 한국재료학회지
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• 제4권5호
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• pp.574-580
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• 1994

본연구는 DSC (dynamic run)의 Barrett method Integral mdthod DGEBA/MDA/MN(malononitrile) DSC DSC pre exponential factor, kinetic parameter 들을 구할 수 있었다.

• Elastomers and Composites
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• 제17권2호
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• pp.77-90
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• 1982

The purpose of this study is to get comparative results on the combined antioxidant systems comprised of MHPPD with IPPD, MHPPD with PBN and MHIPPD with MB when they are individually added to NR and SBR compound. Vulcanization characterstics and physical properties of the combined antioxidants have been studied by means of the Mooney viscometer, the Monsanto disc rheometer and so on. According to the test results, MHPPD with IPPD system has shown faster cure rate, better optimum cure time and shorter scorch time than other systems. The vulcanizate comprised of the MHPPD with IPPD antioxidant system has taken advantage of heat resistance, fluid resistance and antiozone resistance.