• 한국식품영양과학회지
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• 제14권2호
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• pp.164-170
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• 1985

Thiocarbamate wool은 $CS_2$ 및 기타의 SH-reagent로 쉽게 수식(修飾)할 수 있을 뿐만 아니라 가역적(可逆的)으로 사용(使用)이 가능(可能)하며 일반적(一般的)인 조건(條件)에서도 효소(酵素)와 쉽게 결합(結合)하여 재사용(再使用) 및 제거(除去)에 용이(容易)하므로 thiocarbarmate wool의 특이(特異)한 반응성(反應性)을 이용(利用), 효소(酵素)를 고정(固定)하여 공업적(工業的)인 이용(利用) 목적(目的)으로 연구(硏究) 검토(檢討)하였다. $DTC-wool-{\alpha}-amylase$의 일반적(一般的)인 성질(性質)은 $Nat-{\alpha}-amylase$에 비(比)하여 최적온도(最適溫度), 최적(最適) pH, 내열성(耐熱性), 동력학적(動力學的) 동태(動態) 및 활성화(活性化) 에너지 등(等)이 다르게 나타났다. 1) 반응시간(反應時間)은 70분(分)에서 환원탕(環元糖)이 12.2 mg/ml로서 최대(最大)의 활성(活性)을 나타내었고 2) 효소량(酵素量)은 3.0g 으로서 13.5 mg/ml의 환원탕(還元糖)으로 최대(最大)의 활성(活性)을 나타내었으며 3) Michaelis constant $(K_m^*)$는 5.6 mg/ml 였고 $V_{max}^*$는 $370.37\;{\mu}g/ml{\cdot}min^{-1}$이었다. 4) 최적온도(最適溫度)는 $60^{\circ}C$였고 이때의 환원탕(還元糖)의 양(量)은 16 mg/ml 였고 5) 최적(最適) pH는 pH 7.0이었고 95% 이상(以上)의 활성(活性)을 나타낸 pH 안정성(安定性)은 pH $6.0{\sim}7.0$ 이었다. 6) 내열성(耐熱性)은 $Nat-{\alpha}-amylase$ 보다 강(强)하였으며 7) 활성화(活性化) 에너지는 16.6 Kcal/mole 이었다. thiocarbamate wool은 가역(可逆), 재사용(再使用) 및 제거(除去)의 편리(便利)에 큰 의의(意義)를 둘 수 있으며 쉽게 조제(調製)할 수 있는 용이점(容易點)이 있을 뿐 아니라 이 DTC-wool에서 효소(酵素)의 고정(固定)이 室溫(室溫)에서도 짧은 시간(時間) 내(內)에 이루어지며 상당히 높은 고정율(固定率)을 기대할 수 있다. 또 최적온도(最適溫度)가 $60^{\circ}C$이고 최적(最適) pH는 7.0이므로 반응장치(反應裝置) 및 운용(運用)에 별다른 어려움이 없고, 내열성(耐熱性)이 강(强)하므로 쉬운 조건하(條件下)에서 경제적(經濟的)으로 공업적(工業的) 이용(利用)에 유리(有利)하다고 판단(判斷)되어진다.

• Korean Journal of Radiology
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• 제24권10호
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• pp.1028-1037
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• 2023

Objective: To evaluate the computed tomography (CT) features for diagnosing metastatic cervical lymph nodes (LNs) in patients with differentiated thyroid cancer (DTC) and validate the CT-based risk stratification system suggested by the Korean Thyroid Imaging Reporting and Data System (K-TIRADS) guidelines. Materials and Methods: A total of 463 LNs from 399 patients with DTC who underwent preoperative CT staging and ultrasound-guided fine-needle aspiration were included. The following CT features for each LN were evaluated: absence of hilum, cystic changes, calcification, strong enhancement, and heterogeneous enhancement. Multivariable logistic regression analysis was performed to identify independent CT features associated with metastatic LNs, and their diagnostic performances were evaluated. LNs were classified into probably benign, indeterminate, and suspicious categories according to the K-TIRADS and the modified LN classification proposed in our study. The diagnostic performance of both classification systems was compared using the exact McNemar and Kosinski tests. Results: The absence of hilum (odds ratio [OR], 4.859; 95% confidence interval [CI], 1.593-14.823; P = 0.005), strong enhancement (OR, 28.755; 95% CI, 12.719-65.007; P < 0.001), and cystic changes (OR, 46.157; 95% CI, 5.07-420.234; P = 0.001) were independently associated with metastatic LNs. All LNs showing calcification were diagnosed as metastases. Heterogeneous enhancement did not show a significant independent association with metastatic LNs. Strong enhancement, calcification, and cystic changes showed moderate to high specificity (70.1%-100%) and positive predictive value (PPV) (91.8%-100%). The absence of the hilum showed high sensitivity (97.8%) but low specificity (34.0%). The modified LN classification, which excluded heterogeneous enhancement from the K-TIRADS, demonstrated higher specificity (70.1% vs. 62.9%, P = 0.016) and PPV (92.5% vs. 90.9%, P = 0.011) than the K-TIRADS. Conclusion: Excluding heterogeneous enhancement as a suspicious feature resulted in a higher specificity and PPV for diagnosing metastatic LNs than the K-TIRADS. Our research results may provide a basis for revising the LN classification in future guidelines.

• Transactions on Electrical and Electronic Materials
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• 제17권2호
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• pp.57-68
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• 2016

In this study, we present the modern hybrid system based power generation for electric vehicle applications. We describe the hybrid structure of modified current source based DC - DC converters used to extract the maximum power from Photovoltaic (PV) and Fuel Cell system. Due to reduced dc-link capacitor requirement and higher reliability, the current source inverters (CSI) better compared to the voltage source based inverter. The novel control strategy includes Distributed Maximum Power Point Tracking (DMPPT) for photovoltaic (PV) and fuel cell power generation system. The proposed DC - DC converters have been analyzed in both buck and boost mode of operation under duty cycle 0.5>d, 0.5<d<1 and 0.5<d for capable electric vehicle applications. The proposed topology benefits include one common DC-AC inverter that interposes the generated power to supply the charge for the sharing of load in a system of hybrid supply with photovoltaic panels and fuel cell PEM. An improved control of Direct Torque and Flux Control (DTFC) based induction motor fed by current source converters for electric vehicle.In order to achieve better performance in terms of speed, power and miles per gallon for the expert, to accepting high regenerative braking current as well as persistent high dynamics driving performance is required. A simulation model for the hybrid power generation system based electric vehicle has been developed by using MATLAB/Simulink. The Direct Torque and Flux Control (DTFC) is planned using Xilinx ISE software tool in addition to a Modelsim 6.3 software tool that is used for simulation purposes. The FPGA based pulse generation is used to control the induction motor for electric vehicle applications. FPGA has been implemented, in order to verify the minimal error between the simulation results of MATLAB/Simulink and experimental results.