Implementation of Obstacle Avoidance and Target Following based on Machine Learning for Unmanned Aerial Vehicle At Low Altitude

( Yu-hung Lin ),( Tzu-fang Lai ),( Po-yen Lin ),( Tse-min Chen ) 한국농업기계학회 2018 한국농업기계학회 학술발표논문집 Vol.23 No.1

This research developed an integrated system that consist of orientation sensing, balance control, machine vision recognition and shape sorting and avoidance of obstacle with which the UVA will meet the requirement of a low altitude shuttle in orchards and forest. This research also focused on employing machine learning as the main control core to achieve the performances of target following and obstacle avoidance for unmanned aerial vehicle (UAV). In order to keep the balance of a quadcopter, the orientation data from gyroscope and accelerometer will be the inputs of a double loop PID controller. Target is recognized by machine vision. Distances and shapes of obstacles are defined by a laser rangefinder that mounted on the vehicle. The control of UAV depending on the shape of the obstacle, execute different obstacle avoidance strategies. The results of experiment indicated that the complementary filter can compensate the defects of the gyroscope and accelerometer since it fixes steady-state error of gyroscope and oscillation in high frequency of accelerometer. Double-loop PID controller is more stable than single-loop PID controller is. Due to the stability of control board and safety of operators in target following and obstacle avoidance experiment, a three wheels omni robot was employed to conduct the performance evaluation. The final results validate that the novel UAV is equipped with the ability of shuttling among orchards in low-altitude, target following, classification of obstacle shape and obstacle avoidance.

Management of Hyperacute Stroke during the Coronavirus Disease of 2019 Pandemic: The Modified Code Stroke in a Medical Center in Taiwan

Po-Yu Lin,Yu-Ming Chang,Chih-Yuan Huang,Chih-Hao Lin,Ming-Tsung Chuang,Po-Lin Chen,Pi-Shan Sung,Chih-Hung Chen 대한뇌졸중학회 2020 Journal of stroke Vol.22 No.2

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Simple but Organized Neurology Residency Training Improves the Quality of Acute Stroke Care: From the Outset to Long-Term Effect

Yu-Ming Chang,Chun-Min Wang,Po-Yu Lin,Pi-Shan Sung,Sheng-Hsiang Lin,Chih-Hung Chen 대한뇌졸중학회 2021 Journal of stroke Vol.23 No.2

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Thermal Stability, Adhesion and Electrical Studies on (Ti,Zr)Nx Thin Films as Low Resistive Diffusion Barriers between Cu and Si

Cheng-Lin Huang,Chih-Huang Lai,Po-Hao Tsai,Yu-Lin Kuo,Jing-Cheng Lin,Chiapyng Lee 대한금속·재료학회 2014 ELECTRONIC MATERIALS LETTERS Vol.10 No.3

In this study, we investigated the thermal stability, wettability, adhesion and reliability of (Ti,Zr)Nx films used as the diffusion barrier between Cu and Si. (Ti,Zr)Nx films were prepared by DC reactive magnetron sputtering from a Ti-5 at. % Zr alloy target in N2/Ar gas mixtures. A minimum film resistivity of 59.3 μΩ cm was obtained at an N2/Ar flow ratio of 2.75, which corresponds to the near stoichiometric composition (N/(Ti,Zr) ratio ~0.95). The sheet resistance of Cu/(Ti,Zr)N0.95/Si was not significantly increased until annealing above 750°C, indicating good thermal stability. On the other hand, the adhesion energy between Cu and the (Ti,Zr)Nx film was reduced as the N/Ti ratio was increased. To obtain reliable performance on stress-induced-voiding (SIV) and electromigration (EM) tests, we proposed to use (Ti,Zr)/(Ti,Zr)Nx/(Ti,Zr) tri-layers. We suggest that the interfacial adhesion between barrier and Cu plays an important role in reliability. The proposed tri-layer structure may be a promising candidate for a barrier, as it exhibits excellent reliability without increasing resistance.

Catheter Ablation of Ventricular Tachycardia in Arrhythmogenic Right Ventricular Dysplasia/Cardiomyopathy

Fa-Po Chung,Chin-Yu Lin,Yenn-Jiang Lin,Shih-Lin Chang,Li-Wei Lo,Yu-Feng Hu,Ta-Chuan Tuan,Tze-Fan Chao,Jo-Nan Liao,Ting-Yung Chang,Shih-Ann Chen 대한심장학회 2018 Korean Circulation Journal Vol.48 No.10

Arrhythmogenic right ventricular dysplasia/cardiomyopathy (ARVD/C) is predominantly an inherited cardiomyopathy with typical histopathological characteristics of fibro-fatty infiltration mainly involving the right ventricular (RV) inflow tract, RV outflow tract, and RV apex in the majority of patients. The above pathologic evolution frequently brings patients with ARVD/C to medical attention owing to the manifestation of syncope, sudden cardiac death (SCD), ventricular arrhythmogenesis, or heart failure. To prevent future or recurrent SCD, an implantable cardiac defibrillator (ICD) is highly desirable in patients with ARVD/C who had experienced unexplained syncope, hemodynamically intolerable ventricular tachycardia (VT), ventricular fibrillation, and/or aborted SCD. Notably, the management of frequent ventricular tachyarrhythmias in ARVD/C is challenging, and the use of antiarrhythmic drugs could be unsatisfactory or limited by the unfavorable side effects. Therefore, radiofrequency catheter ablation (RFCA) has been implemented to treat the drug-refractory VT in ARVD/C for decades. However, the initial understanding of the link between fibro-fatty pathogenesis and ventricular arrhythmogenesis in ARVD/C is scarce, the efficacy and prognosis of endocardial RFCA alone were limited and disappointing. The electrophysiologists had broken through this frontier after better illustration of epicardial substrates and broadly application of epicardial approaches in ARVD/C. In recent works of literature, the application of epicardial ablation also successfully results in higher procedural success and decreases VT recurrences in patients with ARVD/C who are refractory to the endocardial approach during long-term follow-up. In this article, we review the important evolution on the delineation of arrhythmogenic substrates, ablation strategies, and ablation outcome of VT in patients with ARVD/C.

Platelet-Derived Growth Factor Receptor-α Subunit Targeting Suppresses Metastasis in Advanced Thyroid Cancer In Vitro and In Vivo

( Ching-ling Lin ),( Ming-lin Tsai ),( Yu-hsin Chen ),( Wei-ni Liu ),( Chun-yu Lin ),( Kai-wen Hsu ),( Chien-yu Huang ),( Yu-jia Chang ),( Po-li Wei ),( Shu-huey Chen ),( Li-chi Huang ),( Chia-hwa Lee 한국응용약물학회 2021 Biomolecules & Therapeutics(구 응용약물학회지) Vol.29 No.5

Thyroid cancer is the most common endocrine malignancy. Patients with well-differentiated thyroid cancers, such as papillary and follicular cancers, have a favorable prognosis. However, poorly differentiated thyroid cancers, such as medullary, squamous and anaplastic advanced thyroid cancers, are very aggressive and insensitive to radioiodine treatment. Thus, novel therapies that attenuate metastasis are urgently needed. We found that both PDGFC and PDGFRA are predominantly expressed in thyroid cancers and that the survival rate is significantly lower in patients with high PDGFRA expression. This finding indicates the important role of PDGF/PDGFR signaling in thyroid cancer development. Next, we established a SW579 squamous thyroid cancer cell line with 95.6% PDGFRA gene insertion and deletions (indels) through CRISPR/Cas9. Protein and invasion analysis showed a dramatic loss in EMT marker expression and metastatic ability. Furthermore, xenograft tumors derived from PDGFRA geneedited SW579 cells exhibited a minor decrease in tumor growth. However, distant lung metastasis was completely abolished upon PDGFRA gene editing, implying that PDGFRA could be an effective target to inhibit distant metastasis in advanced thyroid cancers. To translate this finding to the clinic, we used the most relevant multikinase inhibitor, imatinib, to inhibit PDGFRA signaling. The results showed that imatinib significantly suppressed cell growth, induced cell cycle arrest and cell death in SW579 cells. Our developed noninvasive apoptosis detection sensor (NIADS) indicated that imatinib induced cell apoptosis through caspase-3 activation. In conclusion, we believe that developing a specific and selective targeted therapy for PDGFRA would effectively suppress PDGFRA-mediated cancer aggressiveness in advanced thyroid cancers.

The accuracy and clinical applicability of a sensor based electromagnetic nonfluoroscopic catheter tracking system

Shinya Yamada,Li-Wei Lo,Yenn-Jiang Lin,Shih-Lin Chang,Fa-Po Chung,Yu-Feng Hu,Ta-Chuan Tuan,Tze-Fan Chao,Jo-Nan Liao,Chin-Yu Lin,Shih-Ann Chen 대한심장학회 2019 Korean Circulation Journal Vol.49 No.1

Background and Objectives: The differences between electromagnetic-based mapping (EM) and impedance-based mapping (IM) in 3D anatomical reconstruction have not been fully clarified. We aimed to investigate the anatomical accuracy between EM (MediGuide™) and IM (EnSite Velocity™) systems. Methods: We investigated 15 consecutive patients (10 males, mean age 58±9 years) who underwent pulmonary veins (PVs) isolation for paroxysmal atrial fibrillation (PAF). Contrast-enhanced computed tomography (CT) image of the left atrium (LA) was acquired before ablation and the 3D geometry of the LA was constructed using EM during ablation procedure. We measured the 4 PV angles between the main trunk of each PV and the posterior LA after field scaling. Additionally, the posterior LA surface area was measured. The variables were compared to those of CT-based geometry. A control group of 40 patients who underwent conventional PVs isolation using IM were also evaluated. Results: The actual and relative changes of EM and CT-based geometry in all PV angles and posterior LA were significantly smaller compared to those of IM and CT-based geometry. Intraclass correlation coefficient (ICC) between EM and CT-based geometry were 0.871 (right superior pulmonary vein [RSPV]), 0.887 (right inferior pulmonary vein [RIPV]), 0.853 (left superior pulmonary vein [LSPV]), 0.911 (left inferior pulmonary vein [LIPV]), and 0.833 (posterior LA). On the other hand, ICC between IM and CT-based geometry were 0.548 (RSPV), 0.639 (RIPV), 0.691 (LSPV), 0.706 (LIPV), and 0.568 (posterior LA). Conclusions: Image integration with EM enables high accurate visualization of cardiac anatomy compared to IM in PAF ablation.

Harm Avoidance is Correlated with the Reward System in Adult Patients with Attention Deficit Hyperactivity Disorder: A Functional Magnetic Resonance Imaging Study

Tsung-Hua Lu(Tsung-Hua Lu),Shih-Hsien Lin(Shih-Hsien Lin),Mei Hung Chi(Mei Hung Chi),Ching-Lin Chu(Ching-Lin Chu),Dong-Yu Yang(Dong-Yu Yang),Wei Hung Chang(Wei Hung Chang),Po See Chen(Po See Chen),Yen 대한정신약물학회 2023 CLINICAL PSYCHOPHARMACOLOGY AND NEUROSCIENCE Vol.21 No.1

Objective: Hypoactivity in the reward system among patients with attention deficit hyperactivity disorder (ADHD) is a well-known phenomenon. Whether the activity in the reward pathway is related to harm avoidance, such as in sensitivity to punishment, is unclear. Evidence regarding the potential difference between ADHD patients and controls in terms of this association is scarce. Methods: Event-related functional magnetic resonance imaging was conducted on subjects performing the Iowa gambling test. Fourteen adults with ADHD and 14 controls were enrolled in the study. Results: Harm avoidance was found to be positively correlated with the activities of the bilateral orbitofrontal cortex and right insula in individuals with ADHD. A group difference was also confirmed. Conclusion: Understanding the roles of harm avoidance and brain activation during risk tasks is important.

Adjusting optical resonance thickness to increase the conversion efficiency of polymer solar cells

Yu Sheng Tsai,Jian-Shian Lin,Wei-Ping Chu,Po-Hsun Wang,Fuh-Shyang Juang,Ming-Hua Chung,Chin-Ming Chen,Mark O. Liu 한국물리학회 2010 Current Applied Physics Vol.10 No.3

The derivatives of C60, [6,6]-phenyl C61-butyric acid methyl ester (PCBM), and 3-hexylthiophene (P3HT)were dissolved in DCB solvent, then spin coated into an active layer for polymer solar cells. The experimental parameters were studied carefully to obtain the optimum power conversion efficiency (PCE). The primary process for generation of photocurrent in an organic photovoltaic device is the generation of bound electron–hole pairs (excitons) by absorption of energy (photons) from the optical electric field. Modeling was based on the assumption that the photocurrent generation process is the result of the creation and diffusion of photogenerated species (excitons), which are dissociated by charge transfer at the active layer. Improve organic optics absorb by insert organic layer (CuPc or C60) at the active layer/Al interface. This research is divided into two components. First part, we use n-type C60 as transmission layer. When an optimum thickness of C60 is 5 nm, the Jsc of polymer solar cell can be increased from 7.26 mA/㎠ to 7.7 mA/㎠. The Voc decrease is because the energy level of C60 LUMO (lowest unoccupied molecular orbital) at 4.5 eV is higher than the 3.7 eV of PCBM. Second part, we use p-type CuPc as transmission layer. When an optimum thickness of CuPc is 3 nm, the short circuit photo-current density (Jsc) and open circuit voltage (Voc) of polymer solar cell can be increased from 7.26 mA/㎠ to 8.0 mA/㎠ and 0.56–0.58 V, respectively. The reason is the same as C60. The Voc increase is because the energy level of CuPc LUMO (lowest unoccupied molecular orbital) at 3.1 eV is lower than the 3.7 eV of PCBM. The Jsc increase is because the 3 nm of CuPc leads to a constructive interference happened in the active layer and thus optical absorption increases. In this study we used 3 nm of CuPc at the active layer/Al interface to enhance the short circuit current density, and the efficiency was increased to 2.94%.

Comedications and potential drug-drug interactions with direct-acting antivirals in hepatitis C patients on hemodialysis

( Po-yao Hsu ),( Yu-ju Wei ),( Jia-jung Lee ),( Sheng-wen Niu ),( Jiun-chi Huang ),( Cheng-ting Hsu ),( Tyng-yuan Jang ),( Ming-lun Yeh ),( Ching-i Huang ),( Po-cheng Liang ),( Yi-hung Lin ),( Ming-ye 대한간학회 2021 Clinical and Molecular Hepatology(대한간학회지) Vol.27 No.1

Background/Aims: Direct-acting antivirals (DAAs) have been approved for hepatitis C virus (HCV) treatment in patients with end-stage renal disease (ESRD) on hemodialysis. Nevertheless, the complicated comedications and their potential drug-drug interactions (DDIs) with DAAs might limit clinical practice in this special population. Methods: The number, class, and characteristics of comedications and their potential DDIs with five DAA regimens were analyzed among HCV-viremic patients from 23 hemodialysis centers in Taiwan. Results: Of 2,015 hemodialysis patients screened in 2019, 169 patients seropositive for HCV RNA were enrolled (mean age, 65.6 years; median duration of hemodialysis, 5.8 years). All patients received at least one comedication (median number, 6; mean class number, 3.4). The most common comedication classes were ESRD-associated medications (94.1%), cardiovascular drugs (69.8%) and antidiabetic drugs (43.2%). ESRD-associated medications were excluded from DDI analysis. Sofosbuvir/velpatasvir/voxilaprevir had the highest frequency of potential contraindicated DDIs (red, 5.6%), followed by glecaprevir/pibrentasvir (4.0%), sofosbuvir/ledipasvir (1.3%), sofosbuvir/velpatasvir (1.3%), and elbasvir/grazoprevir (0.3%). For potentially significant DDIs (orange, requiring close monitoring or dose adjustments), sofosbuvir/velpatasvir/voxilaprevir had the highest frequency (19.9%), followed by sofosbuvir/ledipasvir (18.2%), glecaprevir/pibrentasvir (12.6%), sofosbuvir/velpatasvir (12.6%), and elbasvir/grazoprevir (7.3%). Overall, lipid-lowering agents were the most common comedication class with red-category DDIs to all DAA regimens (n=62), followed by cardiovascular agents (n=15), and central nervous system agents (n=10). Conclusions: HCV-viremic patients on hemodialysis had a very high prevalence of comedications with a broad spectrum, which had varied DDIs with currently available DAA regimens. Elbasvir/grazoprevir had the fewest potential DDIs, and sofosbuvir/velpatasvir/voxilaprevir had the most potential DDIs. (Clin Mol Hepatol 2021;27:186-196)