Robust Control Design Based-on Integral Sliding-Mode for Systems with Norm-Bounded Uncertainties

Chieh-Chuan Feng,Yung-Yeh Lin 제어로봇시스템학회 2011 제어로봇시스템학회 국제학술대회 논문집 Vol.2011 No.10

Based on the integral sliding-mode control that copes with norm-bounded matched uncertainties, a robust control of L₂-gain performance measure subsequently applied to the system is proposed to handle both nonlinearities and unmatched uncertainties. The similar issue through the use of higher order multimode model has been relaxed. Instead of using exact known multi-mode to express the uncertain system, the norm-bound convex set is a concise way of expressing the model and hence, higher order models needed in the computation can be avoided. In this paper integral sliding-mode control robustly nullifies the matched uncertainties from the first beginning of the process and then, once in the sliding mode, the nonlinearities and unmatched uncertainties are further compensated by the quadratic stability with L₂-gain performance measure to not only stabilize the system but also ensure the satisfaction of performance. The effectiveness is shown in a numerical example.

An immersed boundary method for simulating dynamic and thermal flows with moving rigid boundary

Chuan-Chieh Liao,Chao-An Lin 한국전산유체공학회 2014 한국전산유체공학회 학술대회논문집 Vol.2014 No.10

In the present study, dynamic and thermal fields with moving rigid boundary are investigated by using an immersed-boundary method. This is achieved via direct momentum and energy forcing on a Cartesian grid by combining “solid-body forcing” at solid nodes and interpolation on neighboring fluid nodes, and issue involving the influence of the solid-body forcing is addressed. Grid-function convergence tests also indicate second-order accuracy of this implementation with respect to the L1-norm in time and the L2-norm in space. 3-D simulation of a heated sphere settling under gravity in a static fluid is adopted to examine the validity of the present technique. All computed results are in generally good agreement with experimental measurements. This indicates the capability of the present simple implementation in solving complex-geometry flow problems.

Perceived instructional leadership and teacher self-efficacy of online teaching in Taiwan: Mediating effects of teacher professional community

Chuan-Chung Hsieh,Imam Gunawan,Hui-Chieh Li 한국교육개발원 2023 KEDI Journal of Educational Policy Vol.20 No.1

This study aimed to examine the mediating effects of teacher professional community on the relationship between perceived instructional leadership and teacher self-efficacy of online teaching in Taiwan. Data were collected from elementary and middle school teachers via an online survey using a questionnaire designed with well-developed scales. Analysis showed that perceived instructional leadership has no direct effect on teacher self-efficacy and that teacher professional community mediates fully the relationship between perceived instructional leadership and teacher self-efficacy. Among the four teacher professional community components examined, shared norms showed the most significant mediating effect. Results also revealed no significant difference in the relationships between variables across teachers in elementary and middle schools. Implications for school leadership and teacher learning are discussed.

Spirituality can make a difference: The impact of principals’ spiritual leadership on teachers’ psychological capital and organizational commitment in high-school environment

Chuan-Chung Hsieh,Si-Hsien Lin,Hui-Chieh Li 한국교육개발원 2022 KEDI Journal of Educational Policy Vol.19 No.1

This study explores the impact of principals’ spiritual leadership on teachers’ organizational commitment (OC) and psychological capital (PsyCap) in a high-school environment. We tested the conceptual model using structural equation modeling (SEM) of data collected from a sample of 803 high-school teachers in Taiwan. The results revealed that principals’ spiritual leadership had significant and positive impact on teachers’ PsyCap and that teachers’ PsyCap enhanced their OC. However, principals’ spiritual leadership had no direct effect on teachers’ OC. Teachers’ PsyCap was found to mediate fully the impact of principals’ spiritual leadership on OC. Discussion and implications of the results are presented.

Benzodiazepine-Associated Carcinogenesis

Shih-Chieh Ku,Pei-Shen Ho,Yu-Ting Tseng,Ta-Chuan Yeh,Shu-Li Cheng,Chih-Sung Liang 대한신경정신의학회 2018 PSYCHIATRY INVESTIGATION Vol.15 No.9

Objective Cellular, animal, and human epidemiological studies suggested that benzodiazepines increase the risk of cancer and cancer mortality. Obesity is also clearly linked to carcinogenesis. However, no human studies have examined benzodiazepine-associated carcinogenesis as assessed by changes in cancer biomarkers. Methods A total of 19 patients were recruited, and received a 6-week treatment of 0.5 mg lorazepam. The measured cancer biomarkers were angiopoietin-2 (ANG-2), soluble CD40 ligand, epidermal growth factor, endoglin, soluble Fas ligand (sFASL), heparin-binding EGF-like growth factor (HB-EGF), insulin-like growth factor binding protein, interleukin (IL)-6, IL-8, IL-18, plasminogen activator inhibitor (PLGF), placental growth factor, transforming growth factor (TGF)-α, tumor necrosis factor (TNF)-α, urokinase-type plasminogen (uPA), vascular endothelial growth factor (VEGF)-A, VEGF-C, and VEGF-D. Results Six cancer biomarkers were significantly increased in all patients as a whole. The subgroup analysis revealed a distinct pattern of change. Overweight patients showed a significant increase in 11 cancer biomarkers, including ANG-2, sFASL, HB-EGF, IL-8, PLGF, TGF-α, TNF-α, uPA, VEGF-A, VEGF-C, and VEGF-D. However, normal-weight patients did not show any changes in cancer biomarkers. Conclusion Adiposity may have primed the carcinogenic potential, leading to lorazepam-associated carcinogenesis in overweight patients. Epidemiological studies addressing this issue should consider the potential modulator contributing to benzodiazepine-associated carcinogenesis.

Parameter Optimization of Micromilling Brass Mold Inserts for Microchannels with Taguchi Method

Pin-Chuan Chen,Yu-Chieh Chen,Chang-Wei Pan,Kuan-Ming Li 한국정밀공학회 2015 International Journal of Precision Engineering and Vol. No.

Achieving excellent quality of micromilled surfaces usually requires additional efforts and cost, and Taguchi methodology is anefficient tool in the parameter optimization process. The aim of this study is to explore the optimal cutting parameters for minimalsurface roughness of a micromilled brass mold inset, and the controlling parameters included coolant, spindle speed, feed rate, depthof cut, and the stepover. An orthogonal array and factor analysis were carried out to identify the optimal cutting combination, andthis combination included air coolant, spindle speed of 45,000 rpm, feed rate of 100 mm/min, stepover of 10% of milling bit diameter,and the depth of cut of 5 μm. To further confirm the analysis, multiple confirmation runs were realized and the averagely measuredsurface roughness was 0.03 μm with a stand deviation of 0.004 μm.

Pathogenesis and treatment of non-alcoholic steatohepatitis and its fibrosis

Kuei-Chuan Lee,Pei-Shan Wu,Han-Chieh Lin 대한간학회 2023 Clinical and Molecular Hepatology(대한간학회지) Vol.29 No.1

The initial presentation of non-alcoholic steatohepatitis (NASH) is hepatic steatosis. The dysfunction of lipid metabolism within hepatocytes caused by genetic factors, diet, and insulin resistance causes lipid accumulation. Lipotoxicity, oxidative stress, mitochondrial dysfunction, and endoplasmic reticulum stress would further contribute to hepatocyte injury and death, leading to inflammation and immune dysfunction in the liver. During the healing process, the accumulation of an excessive amount of fibrosis might occur while healing. During the development of NASH and liver fibrosis, the gut-liver axis, adipose-liver axis, and renin-angiotensin system (RAS) may be dysregulated and impaired. Translocation of bacteria or its end-products entering the liver could activate hepatocytes, Kupffer cells, and hepatic stellate cells, exacerbating hepatic steatosis, inflammation, and fibrosis. Bile acids regulate glucose and lipid metabolism through Farnesoid X receptors in the liver and intestine. Increased adipose tissue-derived non-esterified fatty acids would aggravate hepatic steatosis. Increased leptin also plays a role in hepatic fibrogenesis, and decreased adiponectin may contribute to hepatic insulin resistance. Moreover, dysregulation of peroxisome proliferator-activated receptors in the liver, adipose, and muscle tissues may impair lipid metabolism. In addition, the RAS may contribute to hepatic fatty acid metabolism, inflammation, and fibrosis. The treatment includes lifestyle modification, pharmacological therapy, and non-pharmacological therapy. Currently, weight reduction by lifestyle modification or surgery is the most effective therapy. However, vitamin E, pioglitazone, and obeticholic acid have also been suggested. In this review, we will introduce some new clinical trials and experimental therapies for the treatment of NASH and related fibrosis.

Reflections on the role of indigenous principals of Taiwan: The pendulum of ancestral souls and modern standards

Huan-Kan Tseng,Chieh-Chen Wang,Jung-Cheng Chen,Hui-Chieh Li,Chuan-Chung Hsieh 한국교육개발원 2022 KEDI Journal of Educational Policy Vol.19 No.1

The purpose of this qualitative study is to present and shape successful indigenous school principal leadership in Taiwan. We focus particularly on a principal’s attitudes to change, how this influences principal leadership practice and ultimately its contribution to improving school performance. The study captures and analyzes opinions of the stakeholders of an indigenous school on principal leadership to understand how the principal leads the school to successful transformation. The results show that indigenous principal leadership emphasizes harmonious collective relationships, equality of power, spiritual satisfaction and collectivism. The ancestral soul is especially rooted in the principal’s philosophy and values, such that the principal makes good use of the blood ties between schools and tribes, and creates a community of a shared future, facing difficulties together. The findings contribute to the body of knowledge on shaping successful indigenous school principal leadership, which transforms the internal and external environmental factors into the forces for successful school change and benefits the stakeholders.

Acupuncture for ventilator-dependent patients at a hospital-based respiratory care center: A randomized controlled trial

Jia-Ming Chen,Wan-Li Chiang,Bin-Chuan Ji,Ruei-Jhe Jhang,Pei-Hsin Chen,Ya-Lun Li,Che-Ju Chang,Sung-Yen Huang,Tsung-Chieh Lee,Chia-Yun Chen,Ching-Hsiung Lin,Sheng-Hao Lin 한국한의학연구원 2023 Integrative Medicine Research Vol.12 No.4

Background: In intensive care units, mechanical ventilation is an important therapy to help patients with dysp- nea. However, long-term ventilator dependence would consume huge medical resources and increase the risk of morbidity and mortality. The aim of the study was to examine the efficacy of the acupuncture combined with western medical care on ventilator parameters in ventilator-dependent patients. Methods: In this clinical trial, 80 ventilator-dependent patients aged 20 to 80 years old were randomly assigned to acupuncture group and control group in the respiratory care center (RCC) of Changhua Christian Hospital. Besides regular medical care and therapy, participants in the acupuncture group received acupuncture therapy at the same 17 acu-points for 20 minutes once a day, a total of 12 sessions. The ventilator parameters were recorded to evaluate the respiratory efficiency for all participants. The primary outcome was rapid shallow breathing index (RSBI), and secondary outcomes were respiratory rate (RR), tidal volume (TV) and ventilation per minute (MV). Results: Though there was no significant difference in the parameter between the acupuncture group and the control group, we found the trend of decreasing RSBI in the acupuncture group. In subgroup analyses, the mean of RSBI significantly decreased 16.02 (with the SD in 60.84) in acupuncture group, while it increased 17.84 (with the SD in 39.38) in control group (p = 0.036) after 12 sessions. Conclusion: Acupuncture treatment can improve breathing ability of patients with respirator dependence in respiratory care center.

Risk of Diabetic Retinopathy between Sodium-Glucose Cotransporter-2 Inhibitors and Glucagon-Like Peptide-1 Receptor Agonists

Tzu-Yi Lin,Eugene Yu-Chuan Kang,Shih-Chieh Shao,Edward Chia-Cheng Lai,Sunir J. Garg,Kuan-Jen Chen,Je-Ho Kang,Wei-Chi Wu,Chi-Chun Lai,Yih-Shiou Hwang 대한당뇨병학회 2023 Diabetes and Metabolism Journal Vol.47 No.3

Background: To compare risk of diabetic retinopathy (DR) between patients taking sodium-glucose cotransporter-2 inhibitors (SGLT2is) and those taking glucagon-like peptide-1 receptor agonists (GLP1-RAs) in routine care.Methods: This retrospective cohort study emulating a target trial included patient data from the multi-institutional Chang Gung Research Database in Taiwan. Totally, 33,021 patients with type 2 diabetes mellitus using SGLT2is and GLP1-RAs between 2016 and 2019 were identified. 3,249 patients were excluded due to missing demographics, age <40 years, prior use of any study drug, a diagnosis of retinal disorders, a history of receiving vitreoretinal procedure, no baseline glycosylated hemoglobin, or no follow-up data. Baseline characteristics were balanced using inverse probability of treatment weighting with propensity scores. DR diagnoses and vitreoretinal interventions served as the primary outcomes. Occurrence of proliferative DR and DR receiving vitreoretinal interventions were regarded as vision-threatening DR.Results: There were 21,491 SGLT2i and 1,887 GLP1-RA users included for the analysis. Patients receiving SGLT2is and GLP-1 RAs exhibited comparable rate of any DR (subdistribution hazard ratio [SHR], 0.90; 95% confidence interval [CI], 0.79 to 1.03), whereas the rate of proliferative DR (SHR, 0.53; 95% CI, 0.42 to 0.68) was significantly lower in the SGLT2i group. Also, SGLT2i users showed significantly reduced risk of composite surgical outcome (SHR, 0.58; 95% CI, 0.48 to 0.70).Conclusion: Compared to those taking GLP1-RAs, patients receiving SGLT2is had a lower risk of proliferative DR and vitreoretinal interventions, although the rate of any DR was comparable between the SGLT2i and GLP1-RA groups. Thus, SGLT2is may be associated with a lower risk of vision-threatening DR but not DR development.