Microwave-Assisted Synthesis of Core-Crosslinked Star Polymers with Benzophenone Derivatives in the Core

강태현,이형일 한국고분자학회 2019 Macromolecular Research Vol.27 No.5

Core-crosslinked star polymers, which have polyethylene oxide (PEO) as a shell and cross-linked poly(2-[4'-iodobenzoyloxy]-ethyl methacrylate) (PIEMA) with benzophenone derivatives as a core, have been successfully synthesized by an “arm-first” method. PEO-b-PIEMA was prepared via atom transfer radical polymerization (ATRP) of 2-[4'-iodobenzoyloxy]-ethyl methacrylate (4-IEMA) with preformed PEO-Br as a macroinitiator. Core-crosslinked star polymers (CCSP) were efficiently synthesized by ultrafast carbonylation reactions under air by flash microwave irradiation in the presence of dicobalt octacarbonyl in 6 min. Gel permeation chromatography (GPC) trace of CCSP showed a drastic shift to a higher molecular weight when compared to precursor polymer, PEO-b-PIEMA diblock copolymer, indicating that the carbonylation reaction was fully progressed. The CCSP with benzophenone was successfully immobilized on a silicon wafer through a photochemical reaction under UV irradiation.

Age Over 80 is a Possible Risk Factor for Postoperative Morbidity After a Laparoscopic Resection of Colorectal Cancer

강태현,김형욱,김흥대,전호경,한원곤,정경욱 대한대장항문학회 2015 Annals of Coloproctolgy Vol.31 No.6

Purpose: With extended life expectancy, the mean age of patients at the time of diagnosis of colorectal cancer and its treatment, including radical resection, is increasing gradually. We aimed to evaluate the impact of age on postoperative clinical outcomes after a laparoscopic resection of colorectal cancers. Methods: This is a retrospective review of prospectively collected data. Patients with primary colorectal malignancies or premalignant lesions who underwent laparoscopic colectomies between January 2009 and April 2013 were identified. Patients were divided into 6 groups by age using 70, 75, and 80 years as cutoffs: younger than 70, 70 or older, younger than 75, 75 or older, younger than 80, and 80 or older. Demographics, pathological parameters, and postoperative clinical outcomes, including postoperative morbidity, were compared between the younger and the older age groups. Results: All 578 patients underwent a laparoscopic colorectal resection. The overall postoperative complication rate was 21.1% (n = 122). There were 4 cases of operative mortality (0.7%). Postoperative complication rates were consistently higher in the older groups at all three cutoffs; however, only the comparison with a cutoff at 80 years showed a statistically significant difference between the younger and the older groups. Conclusion: Age over 80 is a possible risk factor for postoperative morbidity after a laparoscopic resection of colorectal cancer.

화장품 산업에 있어서 생물화학 공정의 응용사례 연구

강태현,김남기,이희대 한국EHS평가학회 2006 한국EHS평가학회지 Vol.4 No.4

봄철 우리 농장 관리법 - 봄철 산란계 사양관리

강태현,Gang, Tae-Hyeon 대한양계협회 2013 월간 양계 Vol.45 No.3

삼성전자를 팩터로활용한 국내 주식시장요인분석

강태현,유제용,이한송,김장호 대한산업공학회 2018 대한산업공학회 추계학술대회논문집 Vol.2018 No.11

Fc 공학을 통한 치료용 항체 유효성의 증대

강태현 한국생물공학회 2019 BT NEWS Vol.26 No.2

루이스 칸의 공간에 나타난 동양적 특성에 관한 연구

강태현,김동영 대한건축학회지회연합회 2008 대한건축학회지회연합회 학술발표대회논문집 Vol.2008 No.1

The study of Eastern philosophy for building evacuation in the ‘Taoism' to explore the Western architects of the evacuation of the attributes listed in a lot of Louis I. Kahn's philosophy of building through the 'void' I can see the meaning of Louis I. Kahn and was to analyze the relationship between the Lao-tzu. The core of the Lao-tzu to have to go back to the fundamental norms against any of the artificial nature of the claims of the regression. This is Kahn's Salk Institute for Biological Studies show the nature of things through an inner court meeting with the root of the idea that you want to find the basis and the response will be returning to, in the pursuit of modern architecture by the uniformity of space Loss of response to the architecture of relativity, which in itself represents the center disposition in the internal space that will be raised a grade of rank and order to find the root of the construction of a series of action points to a natural end, that Lao-tzu And that the unity in the meeting said.

Preparation of core-cross-linked star polymers with benzophenone derivatives by microwave irradiation

강태현,이형일 한국고분자학회 2015 한국고분자학회 학술대회 연구논문 초록집 Vol.2015 No.10

확률적 변동성을 가진 은닉마르코프 모형을 통한 비트코인 가격의 변동성 추정

강태현,황범석 한국통계학회 2023 응용통계연구 Vol.36 No.1

The stochastic volatility (SV) model is one of the main methods of modeling time-varying volatility. In particular, SV model is actively used in estimation and prediction of financial market volatility and option pricing. This paper attempts to model the time-varying volatility of the bitcoin market price using SV model. Hidden Markov model (HMM) is combined with the SV model to capture characteristics of regime switching of the market. The HMM is useful for recognizing patterns of time series to divide the regime of market volatility. This study estimated the volatility of bitcoin by using data from Upbit, a cryptocurrency trading site, and analyzed it by dividing the volatility regime of the market to improve the performance of the SV model. The MCMC technique is used to estimate the parameters of the SV model, and the performance of the model is verified through evaluation criteria such as MAPE and MSE. Stochastic volatility (SV) 모형은 시변 변동성을 모델링하는 주요한 수단 중 하나이며, 특히 금융시장 변동성의 추정 및 예측, 옵션의 가격 결정 등의 분야에서 활발하게 사용되고 있다. 본 논문은 SV 모형을 활용하여 비트코인 시장의 시변 변동성을 모델링하고자 한다. 시장의 변동성은 국면 전환의 특성을 갖고 있다고 알려져 있으며, 시장의 변동 국면을 나누기 위해 시계열의 패턴을 인식하는 작업에 유용한 hidden Markov model (HMM)을 결합하여 사용하고자 한다. 본 연구는 암호화폐 거래 사이트 업비트의 비트코인 데이터를 활용하여 비트코인의 변동성 모형을 추정하였으며 SV 모형의 성능을 높이기 위하여 시장의 변동 국면을 나누어 분석을 진행하였다. MCMC 기법이 SV 모델의 모수를 추정하는 데 사용되며 MAPE, MSE 등의 평가 기준을 통하여 모델의 성능을 확인하고자 한다.

고유동PP가 혼합된 PP블렌드의 활성화에너지 분석을 통한 열적 산화 거동 연구

강태현,이재식,김동학 한국산학기술학회 2022 한국산학기술학회논문지 Vol.23 No.12

This study was undertaken to investigate the thermal oxidation behaviors of PP/High-Flow PP blends containing different primary to secondary antioxidant ratios and different amounts of total antioxidants in LFT(Long Fiber-reinforced Thermoplastic). We investigated oxidation behaviors by analyzing activation energies calculated from the relationship between temperature and OITs(Oxidation Induced Times) obtained by DSC(Differential Scanning Calorimetry). The inclusion of High-Flow PP accelerated oxidation, but primary antioxidant(s) dose-dependently inhibited oxidation. The relation between OIT and temperature was well-fitted, and activation energies were obtained for different compositions. Activation energy analysis showed it is possible to predict OITs at given processing temperatures and compositions. Optimal antioxidant compositions are needed for high-temperature processing, such as LFT processing using High-Flow PP. 본 연구는 PP(Polypropylene)기반 LFT(Long Fiber-reinforced Thermoplastic) 복합소재에 첨가되는 고유동PP와 1,2차 산화방지제에 대한 열적 산화거동에 대해 연구하였다. Haake Mixer를 통해 산화방지제의 양을 고정하여고유동PP(polypropylene)를 0%, 10%, 20%, 30% 첨가하여 만든 복합체(compound)와 고유동PP 함량이 20%에서1,2차 산화방지제의 비율을 3000ppm 기준으로 1:9, 3:7, 5:5, 7:3, 9:1과 총량을 1000ppm, 2000ppm, 3000ppm, 4000ppm, 5000ppm에 따른 compound를 제조하였다. 이후 복합체(Compound)를 DSC(Differential Scanning Calorimetry)를 통해 OIT(Oxidation Induced Time)를 진행하여 산화거동과 활성화에너지의 경향을 확인하였다. 결과적으로 고유동PP가 첨가되었을 때 열에 의한 산화가 촉진되는 것을 확인하였으며, 1차 산화방지제의 함량이 증가할수록 산화 억제 효과가 높아지는 것을 확인하였다. 또한 개별 처방에서 온도에 따른 산화유도시간 거동이 직선에 잘 부합한다는 것을 확인할 수 있었고, 이로부터 활성화에너지를 얻을 수 있었다. 이와 같은 분석의 결과로부터, 주어진 처방의공정에서 설정 온도에 따른 OIT를 예측할 수 있게 되었으며, 특히 고유동PP가 첨가되는 LFT 가공과 같은 고온 가공시산화방지제의 최적 처방이 필요하다는 것을 확인하였다.