Microstructures and microwave dielectric properties of La1-xBx(Mg0.5Sn0.5)O3 ceramics

Yih-Chien Chen,Yen-Nien Wang,Wei-Cheng Lee 한국물리학회 2012 Current Applied Physics Vol.12 No.3

The microwave dielectric properties of La1-xBx(Mg0.5Sn0.5)O3 ceramics were examined with a view to their exploitation for mobile communication. The La1-xBx(Mg0.5Sn0.5)O3 ceramics were prepared by the conventional solid-state method with various sintering temperatures. The X-ray diffraction patterns of the La0.995B0.005(Mg0.5Sn0.5)O3 ceramics revealed no significant variation of phase with sintering temperatures. A maximum apparent density of 6.58 g/cm3, a dielectric constant (εr) of 19.8, a quality factor (Q × f) of 41,800 GHz, and a temperature coefficient of resonant frequency (sf) of -86 ppm/℃ were obtained for La0.995B0.005(Mg0.5Sn0.5)O3 ceramics that were sintered at 1500 ℃ for 4 h.

Improving microwave dielectric properties of La2.98/3Sr0.01(Mg0.5Sn0.5)O3 ceramics with CuO additive

Yih-Chien Chen 한국물리학회 2012 Current Applied Physics Vol.12 No.2

The microwave dielectric properties of CuO-doped La2.98/3Sr0.01(Mg0.5Sn0.5)O3 ceramics were investigated with a view to their application in microwave devices. CuO-doped La2.98/3Sr0.01(Mg0.5Sn0.5)O3ceramics were prepared by the conventional solid-state method. The X-ray diffraction patterns of CuOdoped La2.98/3Sr0.01(Mg0.5Sn0.5)O3 ceramics exhibited no significant variation of phase with sintering temperature. By adding 0.75 wt.% CuO, a dielectric constant of 20.07, a quality factor (Q × f) of 63,000 GHz, and a temperature coefficient of resonant frequency sf (-77.0 ppm/℃) were obtained when La2.98/3Sr0.01(Mg0.5Sn0.5)O3 ceramics were sintered at 1500 ℃ for 4 h.

Teaching Switching Converter Design Using Problem-Based Learning with Simulation of Characterization Modeling

Shun-Chung Wang,Yih-Chien Chen,Juing-Huei Su 전력전자학회 2010 JOURNAL OF POWER ELECTRONICS Vol.10 No.6

In this paper, teaching in a “switching converter (SC) design” course using problem-based learning (PBL) with dynamicbehavior-model simulation, given at Lunghwa University of Science and Technology (LHU), Taiwan, is proposed. The devised methodology encourages students to design and implement the SCs and regulate the controller’s parameters in frequency domain by using ‘sisitool’ (‘bode’) in the MATLAB toolbox. The environment of PBL with converter characterization modeling and simulation reforms the learning outcome greatly and speeds up the teaching-learning process. To qualify and evaluate the learning achievements, a hands-on project cooperated with the continuous assessment approach is performed to modulate the teaching pace and learning direction in good time. Results from surveys conducted in the end of the course provided valuable opinions and suggestions for assessing and improving the learning effect of the proposed course successively. Positive feedbacks from the examinations, homework, questionnaires, and the answers to the lecturer’s quizzes during class indicated that the presented pedagogy supplied more helpfulness to students in comparisons with conventional teaching paradigm, their learning accomplishments were better than expected as well.

Teaching Switching Converter Design Using Problem-Based Learning with Simulation of Characterization Modeling

Wang, Shun-Chung,Chen, Yih-Chien,Su, Juing-Huei The Korean Institute of Power Electronics 2010 JOURNAL OF POWER ELECTRONICS Vol.10 No.6

In this paper, teaching in a "switching converter (SC) design" course using problem-based learning (PBL) with dynamicbehavior- model simulation, given at Lunghwa University of Science and Technology (LHU), Taiwan, is proposed. The devised methodology encourages students to design and implement the SCs and regulate the controller's parameters in frequency domain by using 'sisitool' ('bode') in the MATLAB toolbox. The environment of PBL with converter characterization modeling and simulation reforms the learning outcome greatly and speeds up the teaching-learning process. To qualify and evaluate the learning achievements, a hands-on project cooperated with the continuous assessment approach is performed to modulate the teaching pace and learning direction in good time. Results from surveys conducted in the end of the course provided valuable opinions and suggestions for assessing and improving the learning effect of the proposed course successively. Positive feedbacks from the examinations, homework, questionnaires, and the answers to the lecturer's quizzes during class indicated that the presented pedagogy supplied more helpfulness to students in comparisons with conventional teaching paradigm, their learning accomplishments were better than expected as well.

Metallic Stent Placement in Hemodialysis Graft Patients after Insufficient Balloon Dilation

Huei-Lung Liang,Huay-Ben Pan,Yih-Huie Lin,Chiung-Yu Chen,Hsiao-Min Chung,Tung-Ho Wu,Kang-Ju Chou,Pin-Hong Lai,Chien-Fang Yang 대한영상의학회 2006 Korean Journal of Radiology Vol.7 No.2

Objective: We wanted to report our experience of metallic stent placement after insufficient balloon dilation in graft hemodialysis patients. Materials and Methods: Twenty-three patients (13 loop grafts in the forearm and 10 straight grafts in the upper arm) underwent metallic stent placement due to insufficient flow after urokinase thrombolysis and balloon dilation. The indications for metallic stent deployment included 1) recoil and/or kinked venous stenosis in 21 patients (venous anastomosis: 17 patients, peripheral outflow vein: four patients); and 2) major vascular rupture in two patients. Metallic stents 8 10mm in diameter and 40 80 mm in length were used. Of them, eight stents were deployed across the elbow crease. Access patency was determined by clinical follow-up and the overall rates were calculated by Kaplan-Meier survival analysis. Results: No procedure-related complications (stent fracture or central migration) were encountered except for a delayed Wallstent shortening/migration at the venous anastomosis, which resulted in early access failure. The overall primary and secondary patency rates ( standard error) of all the vascular accesses in our 23 patients at 3, 6, 12 and 24 months were 69% 9 and 88% 6, 41% 10 and 88% 6, 30% 10 and 77% 10, and 12% 8 and 61% 13, respectively. For the forearm and upper-arm grafts, the primary and secondary patency rates were 51% 16 and 86% 13 vs 45% 15 and 73% 13 at 6 months, and 25% 15 and 71% 17 vs 23% 17 and 73% 13 at 12 months (p = .346 and .224), respectively. Conclusion: Metallic stent placement is a safe and effective means for treating peripheral venous lesions in dialysis graft patients after insufficient balloon dilation. No statistically difference in the patency rates between the forearm and upper-arm patient groups was seen.

The development of Taiwan Fracture Liaison Service network

Lo-Yu Chang,Keh-Sung Tsai,Jen-Kuei Peng,Chung-Hwan Chen,Gau-Tyan Lin,Chin-Hsueh Lin,Shih-Te Tu,I-Chieh Mao,Yih-Lan Gau,Hsusan-Chih Liu,Chi-Chien Niu,Min-Hong Hsieh,Jui-Teng Chien,Wei-Chieh Hung,Rong-S 대한골다공증학회 2018 Osteoporosis and Sarcopenia Vol.4 No.2

Osteoporosis and its associated fragility fractures are becoming a severe burden in the healthcare system globally. In the Asian-Pacific (AP) region, the rapidly increasing in aging population is the main reason accounting for the burden. Moreover, the paucity of quality care for osteoporosis continues to be an ongoing challenge. The Fracture Liaison Service (FLS) is a program promoted by International Osteoporosis Foundation (IOF) with a goal to improve quality of postfracture care and prevention of secondary fractures. In this review article, we would like to introduce the Taiwan FLS network. The first 2 programs were initiated in 2014 at the National Taiwan University Hospital and its affiliated Bei-Hu branch. Since then, the Taiwan FLS program has continued to grow exponentially. Through FLS workshops promoted by the Taiwanese Osteoporosis Association (TOA), program mentors have been able to share their valuable knowledge and clinical experience in order to promote establishments of additional programs. With 22 FLS sites including 11 successfully accredited on the best practice map, Taiwan remains as one of the highest FLS coverage countries in the AP region, and was also granted the IOF Best Secondary Fracture Prevention Promotion award in 2017. Despite challenges faced by the TOA, we strive to promote more FLS sites in Taiwan with a main goal of ameliorating further health burden in managing osteoporotic patients.