Trajectory Learning and Reproduction for Tracked Robot Based on Bagging-GMM/HSMM

Lu En,Zhao Zhan,Yin Jianjun,Luo Chengming,Tian Zhongming 대한전기학회 2023 Journal of Electrical Engineering & Technology Vol.18 No.6

Learning and reproducing the tracked robot’s demonstration trajectory is a promising intelligent path planning solution that can summarize and extract the relevant characteristics of the tracked robot’s desired trajectory. However, the existing methods are difficult to ensure the robustness when there are deviations in the demonstration trajectory data or when the task constraints are added. In order to address the problem, this paper proposes a novel trajectory learning and reproduction method for tracked robots that is based on Bagging algorithm and GMM/HSMM. The Bagging algorithm is used to randomly resample the demonstration trajectory data and construct the sub trajectory data sets. Then, GMM/HSMM is used to train and learn these sub trajectory data sets, and the output probability density function of the hidden state and the Gaussian component with the largest average position probability are selected as the motion elements. According to the mean and variance of these motion elements, the least square method is used to reconstruct the tracked robot’s trajectory. On the basis of using the IPSO algorithm to optimize the position of constraint points in each sub trajectory data sets, combined with the weight method, the learning results are integrated to realize the trajectory reproduction of a tracked robot under task constraints. The final results and analysis show that the proposed method can successfully realize the trajectory learning and reproduction of tracked robot, as well as ensure that the reproduced trajectory can pass through the required task constraint points without increasing the algorithm’s complexity.

Isolated and Complex Scimitar Vein Anomalies and Their Differentiation from the Meandering Right Pulmonary Vein

Meng-Luen Lee 연세대학교의과대학 2007 Yonsei medical journal Vol.48 No.6

Purpose: Four pediatric patients with isolated (the adult form) and complex (the infantile form) scimitar vein anomalies were reviewed and compared with patients with meandering right pulmonary veins. Materials and Methods: From January 1990 to December 2006, 4 female patients, aged 2 days to 3.5 years, with isolated and complex scimitar vein anomalies were retrospectively studied. The clinical features, chest radiographs, echocardiography, magnetic resonance imaging, magnetic resonance angiography, computer tomography, bronchography, cardiac catheterization with angiography, surgery, and autopsy were reviewed to substantiate the diagnosis of isolated and complex scimitar vein anomalies. Results: Clinical manifestations were lung infections with radiographic scimitar signs in 4 patients (3 right; 1 left), respiratory distress, congestive heart failure, pulmonary hypertension and/or cyanosis in 3 patients, dextrocardia, heterotaxy, and/or right atrial isomerism in 2 patients, as well as dextroversion, right bronchial isomerism, bronchial stenosis, and/or sepsis in 1 patient. Two patients with right atrial isomerism expired. Conclusion: The clinical discrimination between scimitar vein anomaly with and without cardiovascular and bronchopulmonary malformations is crucial for the outcomes vary.

Diagnosis and Management of Congenital Coronary Arteriovenous Fistula in the Pediatric Patients Presenting Congestive Heart Failure and Myocardial Ischemia

Meng-Luen Lee,Ming Chen 연세대학교의과대학 2009 Yonsei medical journal Vol.50 No.1

Purpose: Four pediatric patients with congenital coronary arteriovenous fistula (CAVF) were reported to remind pediatric practitioners and cardiologists of its diagnosis and management. Materials and Methods: Four pediatric patients with congenital CAVF from June 1999 to November 2007 were included in this retrospective study. Study modalities included reviews of patients' profiles of clinical features, chest radiograph, Doppler echocardiography, cardiac catheterization with angiography, myocardial perfusion scan, and computed tomography. Results: All 4 patients were symptomatic. The clinical symptoms and signs were feeding problem, continuous murmur, tachycardia, tachypnea, cardiomegaly, and exertional chest pain. Myocardial enzyme was elevated in 1 patient. Echocardiography showed dilatation of the coronary artery in all 4 patients, and traced down its origin in 3 and drainage in 4. The fistulas originated from the right coronary artery in 2 patients and left coronary artery in 2, and were drained into the right ventricle in 2, right atrium in 1, and pulmonary artery in 1. Single left coronary artery was found in 1 patient. The pulmonary-to-systemic blood flow ratios ranged from 1.2 to 2.5. Transcatheter coil occlusion was successfully performed in 4 patients through a coaxial delivery system. The symptoms and signs of congestive heart failure and myocardial ischemia disappeared after the procedure. Conclusion: Diagnosis of congenital CAVF could be achieved by appreciation of continuous murmur over area unusual for the ductus, and by scrupulous examination of echocardiography as well as angiography of the coronary artery through which coaxial transcatheter coil occlusion could be performed successfully.

Diagnosis of the Double Aortic Arch and Its Differentiation from the Conotruncal Malformations

Meng-Luen Lee 연세대학교의과대학 2007 Yonsei medical journal Vol.48 No.5

Outcomes in Neonates with Pulmonary Atresia and Intact Ventricular Septum Underwent Pulmonary Valvulotomy and Valvuloplasty Using a Flexible 2-French Radiofrequency Catheter

Meng-Luen Lee,Lon-Yen Tsao,Han-Yao Chiu,Ming Chen,Ing-Sh Chiu 연세대학교의과대학 2009 Yonsei medical journal Vol.50 No.2

Purpose : Outcomes in 6 neonates with pulmonary atresia and intact ventricular septum (PAIVS) undergoing radiofrequency pulmonary valvulotomy and valvuloplasty (RPVV) were reported to identify the factors favorable for RPVV as the treatment of choice. Materials and Methods: From May 2000 to January 2008, 6 patients with PAIVS were included in this retrospective study. They were aged 1 day to 90 days old. Study modalities included review of recordings of presentations and profiles of chest radiography, electrocardiography, echocardiography, and cardiac catheterization with angiography. Hemodynamic profiles from the echocardiography and the cardiac catheterization were analyzed. Results: Echocardiography showed severe tricuspid regurgitation, membranous atresia of the pulmonary valve, intact ventricular septum, patent ductus arteriosus, and hypoplastic right ventricle in 6 patients. The pulmonary valve annulus were 4.2 to 6.9 mm in diameters, and those of the tricuspid valve were 7.1 to 10.1 mm. Elevated serum level of cardiac enzymes were found in 1 patient with ventriculocoronary communication (VCC). At cardiac catheterization, the ratio of systolic pressure of the right ventricle to that of the left ventricle ranged from 1.43 to 2.33 before RPVV, and from 0.54 to 1.15 after RPVV (p=0.027). The pressure gradients ranged from 76 to 136 mmHg before RPVV, and from 15 to 39 mmHg after RPVV (p=0.028). The echocardiographic gradients ranged from 16 to 32 mmHg within 24 hours after RPVV, and from 15 to 50 mmHg at the follow-ups. Conclusion: RPVV can be a treatment of choice for neonates with PAIVS, if there is patent infundibulum, no right-ventricular dependent coronary circulation, and adequate tricuspid valve and pulmonary valve. Purpose : Outcomes in 6 neonates with pulmonary atresia and intact ventricular septum (PAIVS) undergoing radiofrequency pulmonary valvulotomy and valvuloplasty (RPVV) were reported to identify the factors favorable for RPVV as the treatment of choice. Materials and Methods: From May 2000 to January 2008, 6 patients with PAIVS were included in this retrospective study. They were aged 1 day to 90 days old. Study modalities included review of recordings of presentations and profiles of chest radiography, electrocardiography, echocardiography, and cardiac catheterization with angiography. Hemodynamic profiles from the echocardiography and the cardiac catheterization were analyzed. Results: Echocardiography showed severe tricuspid regurgitation, membranous atresia of the pulmonary valve, intact ventricular septum, patent ductus arteriosus, and hypoplastic right ventricle in 6 patients. The pulmonary valve annulus were 4.2 to 6.9 mm in diameters, and those of the tricuspid valve were 7.1 to 10.1 mm. Elevated serum level of cardiac enzymes were found in 1 patient with ventriculocoronary communication (VCC). At cardiac catheterization, the ratio of systolic pressure of the right ventricle to that of the left ventricle ranged from 1.43 to 2.33 before RPVV, and from 0.54 to 1.15 after RPVV (p=0.027). The pressure gradients ranged from 76 to 136 mmHg before RPVV, and from 15 to 39 mmHg after RPVV (p=0.028). The echocardiographic gradients ranged from 16 to 32 mmHg within 24 hours after RPVV, and from 15 to 50 mmHg at the follow-ups. Conclusion: RPVV can be a treatment of choice for neonates with PAIVS, if there is patent infundibulum, no right-ventricular dependent coronary circulation, and adequate tricuspid valve and pulmonary valve.

Revascularization of Concurrent Renal and Cerebral Artery Stenosis in a 14-Year-Old Girl with Takayasu Arteritis and Moyamoya Syndrome

Meng-Luen Lee,Ming-Yuh Chang,Tung-Ming Chang,Rei-Cheng Yang,Ming-Che Chang,Albert D. Yang 대한의학회 2018 Journal of Korean medical science Vol.33 No.10

Concurrent involvement of bilateral renal and cerebral arteries, usually incurred as stenosis is rare in childhood-onset Takayasu arteritis (c-TA). We report the case of a 14-year-old girl, with c-TA, presenting with transient ischemic attack after endovascular revascularization for renal artery stenosis and cerebrovascular stroke after surgical revascularization for cerebral artery stenosis associated with childhood-onset moyamoya syndrome. We deem th decrease of blood pressure by endovascular revascularization and improvement of cerebral perfusion by surgical revascularization may have jeopardized the cerebral deep watershed zone to cerebral ischemia followed by cerebral hyperperfusion syndrome and caused transient ischemic attack and cerebrovascular stroke in our patient. Revascularization could be a double-edge sword for c-TA patients presenting with concomitant renal artery stenosis and cerebral artery stenosis, and should be performed with caution. Quantitative analysis of cerebral blood flow by brain magnetic resonance imaging and angiography should be performed within 48 hours after surgical revascularization in c-TA.

The Role of Communication Style and Culture in Adherence to Robot Recommendations

Pei-Luen Patrick Rau 한국HCI학회 2013 한국HCI학회 학술대회 Vol.2013 No.1

A Systematic Classification of the Congenital Bronchopulmonary Vascular Malformations: Dysmorphogeneses of the Primitive Foregut System and the Primitive Aortic Arch System

Meng-Luen Lee,Hung-Chi Lue,Ing-Sh Chiu,Han-Yao Chiu,Lon-Yen Tsao,Ching-Yuan Cheng,Albert D. Yang 연세대학교의과대학 2008 Yonsei medical journal Vol.49 No.1

Purpose: We reviewed the cases of 33 patients from our clinic and 142 patients from the literature with congenital bronchopulmonary vascular malformations (BPVM), systematically analyzed the bronchopulmonary airways, pulmonary arterial supplies, and pulmonary venous drainages, and classified these patients by pulmonary malinosculation (PM). Materials and Methods: From January 1990 to January 2007, a total of 33 patients (17 men or boys and 16 women or girls), aged 1 day to 24 years (median, 2.5 months), with congenital BPVM were included in this study. Profiles of clinical manifestations, chest radiographs, echocardiographs, esophagographs, computer tomography (CT), magnetic resonance imaging (MRI), magnetic resonance angiography (MRA), cardiac catheterizations with angiography, contrast bronchographs, bronchoscopies, chromosomal studies, surgeries, and autopsies of these patients were analyzed to confirm the diagnosis of congenital BPVM. A total of 142 cases from the literature were also reviewed and classified similarly. Results: The malformations of our 33 patients can be classified as type A isolated bronchial PM in 13 patients, type B isolated arterial PM in three, type C isolated venous PM in two, type D mixed bronchoarterial PM in five, type F mixed arteriovenous PM in one, and type G mixed bronchoarteriovenous PM in nine. Conclusion: Dysmorphogeneses of the primitive foregut system and the primitive aortic arch system may lead to haphazard malinosculations of the airways, arteries, and veins of the lung. A systematic classification of patients with congenital BPVM is clinically feasible by assessing the three basic bronchovascular systems of the lung independently.

Biportal Endoscopic Transforaminal Lumbar Interbody Fusion Using Double Cages: Surgical Techniques and Treatment Outcomes

Jwo-Luen Pao 대한척추신경외과학회 2023 Neurospine Vol.20 No.1

Objective: To describe the surgical techniques and the treatment outcomes of biportal endoscopic transforaminal lumbar interbody fusion (BETLIF) using double cages. Methods: This study included 89 patients with 114 fusion segments between July 2019 and May 2021. One pure polyetheretherketone (PEEK) cage and 1 composite titanium-PEEK cage were used for interbody fusion. Clinical outcomes measures included visual analogue scale (VAS) scores for lower back pain and leg pain, Oswestry Disability Index (ODI), and Japanese Orthopedic Association (JOA) scores. Computed tomography (CT) of the lumbar spine 1 year postoperatively was used to evaluate the Bridwell interbody fusion grades. Results: There were significant improvement in VAS for lower back pain from 5.2 ± 3.1 to 1.7 ± 2.1, VAS for leg pain from 6.3 ± 2.5 to 1.7 ± 2.0, ODI from 46.7 ± 17.0 to 12.7 ± 16.1, and JOA score from 15.6 ± 6.3 to 26.4 ± 3.2. The p-values were all < 0.001. The average hospital stay was 5.7 ± 1.1 days. The CT studies available for 60 fusion segments showed successful fusion (Bridwell grade I or grade II) in 56 segments (93.3%). Significant cage subsidence of more than 2 mm was only noted in 3 segments (5.0%). Complications included 1 dural tear, 2 pedicle screws malposition, and 2 epidural hematomas, in which 2 patients required reoperations. Conclusion: BETLIF with double cages provided good neural decompression and a sound environment for interbody fusion with a big cage footprint, a large amount of bone graft, endplate preservation, and segmental stability.

Major Determinants and Long-Term Outcomes of Successful Balloon Dilatation for the Pediatric Patients with Isolated Native Valvular Pulmonary Stenosis: A 10-Year Institutional Experience

Meng-Luen Lee,Jui-Wen Peng,Guo-Jhueng Tu,San-Yi Chen,Jyong-You Lee,Shu-Lin Chang 연세대학교의과대학 2008 Yonsei medical journal Vol.49 No.3

Purpose: We report herein major determinants and long- term outcomes of balloon dilatation (BD) for 27 pediatric patients with isolated native valvular pulmonary stenosis (VPS). Materials and Methods: From May 1997 to May 2003, 27 pediatric patients with VPS (pressure gradients≧ 40mmHg) were enrolled in this retrospective study. Single- balloon maneuver was applied in 26 patients, and double- balloon maneuver in 1. After BD, the pressure gradients were documented simultaneously by pullback maneuver by cardiac catheterization and echocardiography within 24 hours, at 1- month, 3-month, 1-year, and 4-to-10-year follow-ups. Results: Before BD, the echocardiographic gradients ranged from 40 to 101mmHg (61±19, 55), and from 40 to 144mmHg (69 ±32, 60) by pressure recordings. After BD, the gradients ranged from 12 to 70mmHg (29±13, 27) by pressure recording (p<0.001), and from 11 to 64mmHg (27±12, 26) by echocardiography within 24 hrs (p<0.001). The ratios of the systolic pressure of the right ventricle to those of the left ventricle were 55 to 157% (89±28, 79%) before BD, and 30 to 79% (47±13, 42%) after BD (p<0.001). Follow-up (7.7±5.7, 4.5 years) echocardiographic gradients ranged from 11 to 61mmHg (25±11, 24). Two patients did not have immediate success owing to infundibular spasm. Improved right ventricular compliance could be accounted for the ultimate success in these 2 patients. The ultimate successful rate was 100%. Conclusion: BD can achieve excellent long-term outcomes in the pediatric patients with isolated native VPS.