Sensor-based Path Planning: The Two-Identical-Link Hierarchical Generalized Voronoi Graph

Ming-Lei Shao,이지영,한창수,신규식 한국정밀공학회 2015 International Journal of Precision Engineering and Vol. No.

We present a new roadmap based on a generalized Voronoi graph (GVG) for two-identical-link ( L2) robots to explore an unknown planar environment. It is called the L2 hierarchical generalized Voronoi graph (L2-HGVG). The L2 robot is formed by two equal length rods and a revolute joint between them. The configuration of the robot possesses four degree-of-freedom, two for position and two for orientation, and hence the roadmap is one-dimensional in an unknown configuration space R2 × T2. L2-HGVG is defined in terms of workspace distance measurements using only sensor information without prior knowledge of the environment, with the robot having the maximum distance from obstacles, and is therefore optimum in a point of view for exploration and obstacle avoidance.

A Study on the influence of Subsidiary Characteristics on Parental Control

Ming lei XIE,Shun zhou CHEN 한국유통과학회 2017 KODISA ICBE (International Conference on Business Vol.2017 No.-

Subsidiary characteristics are important factors in Group's control, but the existing research on this issue is lacking in empirical test. Through questionnaire survey, this paper examines the impact on the group control of the company size, business sophistication and business strategy of the subsidiary. The findings are as follows: the larger the subsidiaries, the more the parent company should exercise formal control; the greater the differentiation in subsidiary's business strategy, the more the parent should lower the degree of control, and the more the use of informal control. The relationship between subsidiary business maturity and the group control has not been verified.

Impact of Esophageal Motility on Microbiome Alterations in Symptomatic Gastroesophageal Reflux Disease Patients With Negative Endoscopy: Exploring the Role of Ineffective Esophageal Motility and Contraction Reserve

Ming-Wun Wong,I-Hsuan Lo,Wei-Kai Wu,Po-Yu Liu,Yu-Tang Yang,Chun-Yao Chen,Ming-Shiang Wu,Sunny H Wong,Wei-Yi Lei,Chih-Hsun Yi,Tso-Tsai Liu,Jui-Sheng Hung,Shu-Wei Liang,C Prakash Gyawali,Chien-Lin Che 대한소화기 기능성질환∙운동학회 2024 Journal of Neurogastroenterology and Motility (JNM Vol.30 No.3

Background/AimsIneffective esophageal motility (IEM) is common in patients with gastroesophageal reflux disease (GERD) and can be associated with poor esophageal contraction reserve on multiple rapid swallows. Alterations in the esophageal microbiome have been reported in GERD, but the relationship to presence or absence of contraction reserve in IEM patients has not been evaluated. We aim to investigate whether contraction reserve influences esophageal microbiome alterations in patients with GERD and IEM. MethodsWe prospectively enrolled GERD patients with normal endoscopy and evaluated esophageal motility and contraction reserve with multiple rapid swallows during high-resolution manometry. The esophageal mucosa was biopsied for DNA extraction and 16S ribosomal RNA gene V3-V4 (Illumina)/full-length (Pacbio) amplicon sequencing analysis. ResultsAmong the 56 recruited patients, 20 had normal motility (NM), 19 had IEM with contraction reserve (IEM-R), and 17 had IEM without contraction reserve (IEM-NR). Esophageal microbiome analysis showed a significant decrease in microbial richness in patients with IEM-NR when compared to NM. The beta diversity revealed different microbiome profiles between patients with NM or IEM-R and IEM-NR (P = 0.037). Several esophageal bacterial taxa were characteristic in patients with IEM-NR, including reduced Prevotella spp. and Veillonella dispar, and enriched Fusobacterium nucleatum. In a microbiome-based random forest model for predicting IEM-NR, an area under the receiver operating characteristic curve of 0.81 was yielded. ConclusionsIn symptomatic GERD patients with normal endoscopic findings, the esophageal microbiome differs based on contraction reserve among IEM. Absent contraction reserve appears to alter the physiology and microbiota of the esophagus.

Fixed-time Coordinated Attitude Tracking Control for Spacecraft Formation Flying Considering Input Amplitude Constraint

Ming-Lei Zhuang,Shen-Min Song 제어·로봇·시스템학회 2022 International Journal of Control, Automation, and Vol.20 No.7

This paper studies the fixed-time stability of coordinated attitude tracking control under consideration of an input amplitude constraint. The attitude dynamics is described by rotation matrix, which avoids the unwinding phenomenon. By designing and analyzing the proposed nonsingular terminal sliding mode surfaces (NTSMSs) step by step, a novel saturated NTSMS is finally established. This NTSMS has theoretical and practical advantages over other existing NTSMSs, such as its fixed-time convergence property and boundedness. Based on it, two fixed-time coordinated controllers are developed. The first one effectively decreases the amplitude of the control input, whereas the second prevents saturation. Both controllers keep the attitude synchronization task be finished in fixed-time and provide better performance than existing controllers. Specific expressions of the regions to which the system states to converge are obtained using Lyapunov stability theory. Simulation results testify the correctness of the proposed theorems.

Sensor-Based Path Planning for Planar Two-identical-Link Robots by Generalized Voronoi Graph

Ming-Lei Shao(소명뢰),Kyoo-Sik Shin(신규식) 한국산학기술학회 2014 한국산학기술학회논문지 Vol.15 No.12

일반화된 보로노이 그래프(GVG)는 자율 주행 로봇을 위한 일종의 로드맵으로서. GVG는 선서에다 받은 정보만 사용하여 작업 공간거리의 계산에 따라 정의를 한다. 로봇은 장애물까지의 최대 거리를 검출할 수 있기 때문에 포인트 뷰에서 GVG의 최적은 정출 몇 장애물 회피이다. 로봇의 경우에는, GVG는 가장 안전적인 길이라고 할 수 있다. 따라서 높이 링크 로봇의 GVG가장거리에 대한 연구가 매우 필요하다. 기존 연구에서 점(point) 로봇을 위한 GVG(point-GVG)와 로드 로봇을 위한 GVG(rod-GVG)가 발표되었다. 이 논문은 더 고차원의 로봇인 두 개의 동일 링크가 관절로 연결된 (tow-identical-link; L2) 로봇을 위한 GVG(L2-GVG)에 대한 연구이다. L2-GVG는 미지의 평면 작업공간에서 움직이는 L2로봇의 짜임새 공간R²×T²상에서 로드맵을 생성하되, 이전 연구와 마찬가지로 지역적 센서 정보만을 이용해 로봇이 스스로 주행하면서 맵을 만들어 낸다. 이 논문에서는 이전 point-GVG와 rod-GVG에서는 나타나지 않는, 관절이 존재하여 생기는 복잡한 특성에 대해서 분석한다. 이는 다관절 로봇으로의 확장에 중요한 초석이 될 것이다. The generalized Voronoi graph (GVG) is a topological map of a constrained environment. This is defined in terms of workspace distance measurements using only sensor-provided information, with a robot having a maximum distance from obstacles, and is the optimum for exploration and obstacle avoidance. This is the safest path for the robot, and is very significant when studying the GVG edges of highly articulated robots. In previous work, the point-GVG edge and Rod-GVG were built with point robot and rod robot using sensor-based control. An attempt was made to use a higher degree of freedom robot to build GVG edges. This paper presents GVG-based a new local roadmap for the two-link robot in the constrained two-dimensional environment. This new local roadmap is called the two-identical-link generalized Voronoi graph (L2-GVG). This is used to explore an unknown planar workspace and build a local roadmap in an unknown configuration space R² × T² for a planar two-identical-link robot. The two-identical-link GVG also can be constructed using only sensor-provided information. These results show the more complex properties of two-link-GVG, which are very different from point-GVG and rod-GVG. Furthermore, this approach draws on the experience of other highly articulated robots.

Robust singular perturbation control for 3D path following of underactuated AUVs

Lei Ming,Li Ye,Pang Shuo 대한조선학회 2021 International Journal of Naval Architecture and Oc Vol.13 No.1

This paper presents a novel control scheme for the three-dimensional (3D) path following of underactuated Autonomous Underwater Vehicle (AUVs) subject to unknown internal and external disturbances, in term of the time scale decomposition method. As illustration, two-time scale motions are first artificially forced into the closed-loop control system, by appropriately selecting the control gain of the integrator. Using the singular perturbation theory, the integrator is considered as a fast dynamical control law that designed to shape the space configuration of fast variable. And then the stabilizing controller is designed in the reduced model independently, based on the time scale decomposition method, leading to a relatively simple control law. The stability of the resultant closed-loop system is demonstrated by constructing a composite Lyapunov function. Finally, simulation results are provided to prove the efficacy of the proposed controller for path following of underactuated AUVs under internal and external disturbances.

GOLPH3, a Good Prognostic Indicator in Early-stage NSCLC Related to Tumor Angiogenesis

Lu, Ming,Tian, Yu,Yue, Wei-Ming,Li, Lin,Li, Shu-Hai,Qi, Lei,Hu, Wen-Si,Gao, Cun,Si, Li-Bo,Tian, Hui Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.14

Background: Golgi phosphoprotein-3 (GOLPH3) is implicated in cancer development and progression. The aim of this study was to evaluate the prognostic significance of GOLPH3 protein and its association with tumor angiogenesis in patients with early-stage NSCLC. Materials and Methods: Immunohistochemistry was performed to determine GOLPH3 protein expression and allow assessment of intratumoral microvessel density (MVD) by counting CD-34 positive immunostained endothelial cells. Correlations of expression with MVD, clinicopathologic features and clinical prognosis were analyzed. Results: A notably higher level of GOLPH3 expression was found in early-stage NSCC tissues at the protein level. However, we do not find any correlation between GOLPH3 expression and clinicopathologic features (p>0.05), although higher MVD was positively associated with GOLPH3 overexpression (p<0.001). Expression of GOLPH3 was found to be an independent prognostic factor in early-stage NSCLC patients, those expressing high levels of GOLPH3 exhibiting a substantially lower 5-year overall survival than GOLPH3-negative patients (adjusted HR =1.899, 95% CI: 1.021-3.532, p=0.043). Conclusions: High expression of the GOLPH3 protein is common in early-stage NSCC, and is closely associated with tumor progression, increased tumor angiogenesis, and poor survival. We conclude a possibility of its use as a diagnostic and prognostic marker in early-stage NSCC patients.

Development of a 2-Chamber Culture System for Impedimetric Monitoring of Cell-cell Interaction

Kin Fong Lei,Meng-Tsan Tsai,Ming-Hong Zhong,Chia-Hao Huang,Ngan-Ming Tsang,Ming-Yih Lee 한국바이오칩학회 2017 BioChip Journal Vol.11 No.2

In cancer research, study of cell-cell interaction is important to understand tumor initiation, progression, metastasis, and therapeutic resistance. Conventionally, transwell system was adopted and cell proliferation was quantified by end-point bio-assays. The operations are labor-intensive and time-consuming while studying of the dynamic cellular responses of cell-cell interaction. Although impedance measurement was suggested to be a promising technique to monitor cellular responses, electrodes cannot be integrated into the transwell for the measurement purpose. In this work, a 2-chamber culture system incorporated with impedance measurement technique was developed to quantitatively study cell-cell interaction. The chamber was composed of 2 sub-chambers separated with a barrier. By this design, two types of cells could be independently cultured and concurrently monitored under common medium supplied. Cell-cell interaction was demonstrated by aberrant cell proliferation induced by the EGF secreted from the transfected cells cultured on another sub-chamber. Real-time and non-invasive monitoring of cell-cell interaction was successfully demonstrated. This work provides a practical solution for monitoring the dynamic cellular responses of cellcell interaction during the culture course. It is a reliable and convenient platform and facilitate more quantitative assessments in cancer research.

Survival Analysis of Oral Squamous Cell Carcinoma in a Subgroup of Young Patients

Fan, Yi,Zheng, Lei,Mao, Ming-Hui,Huang, Ming-Wei,Liu, Shu-Ming,Zhang, Jie,Li, Sheng-Lin,Zheng, Lei,Zhang, Jian-Guo Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.20

Oral squamous cell carcinoma (OSCC) is predominantly a disease of middle-aged men with long-term exposure to tobacco and alcohol. An increasing trend has been reported at a younger age worldwide. Clinical records of 100 patients under the age of 45 years treated specifically for oral cavity SCC in our hospital during a 10-year period were retrospectively analyzed to calculate the survival rates. An obvious male predominance coincided with smoking trend among Chinese young individuals and female patients were more likely to have no traditional risk factors such as smoking or drinking. The 5-year overall survival rate and disease-free survival rate were 61.0% and 75.5%, respectively, consistent with other published series over the decade showing a relatively better survival among the young. No significant differences clearly correlated with outcome when comparing non-smokers non-drinkers to ever-smokers and ever drinkers (P>0.05). Overall survival rate and disease free survival rate was found to be significantly higher in patients with early-stage disease than with advanced stage disease (P=0.001, P=0.009 respectively). The strong influence of clinical stage on prognosis emphasizes the importance of early diagnosis and treatment of oral malignancies for this unique clinical subgroup.

Valsartan regulates TGF-b/Smads and TGF-b/p38 pathways through lncRNA CHRF to improve doxorubicin-induced heart failure

Lei Chen,Kui-Po Yan,Xin-Can Liu,Wei Wang,Chao Li,Ming Li,Chun-Guang Qiu 대한약학회 2018 Archives of Pharmacal Research Vol.41 No.1

This study investigated the interaction amongvalsartan (VAL), TGF-b pathways, and long non-codingRNA (lncRNA) cardiac hypertrophy-related factor (CHRF)in doxorubicin (DOX)-induced heart failure (HF), andexplored their roles in DOX-induced HF progression. HFmice models in vivo were constructed by DOX induction. The expression of CHRF and TGF-b1 in hearts wasdetected, along with cardiac function, caspase-3 activity,and cell apoptosis. Primary myocardial cells were pretreatedwith VAL, followed by DOX induction in vitro forfunctional studies, including the detection of cell apoptosiswith terminal deoxynucleotidyl transferase dUTP nick-endlabeling and the expression of proteins associated withTGF-b1 pathways. HF models were established in vivo andin vitro. Expression of CHRF and TGF-b1 was up-regulated,and cell apoptosis and caspase-3 activity wereincreased in the hearts and cells of the HF models. VALsupplementation alleviated the cardiac dysfunction andinjury in the HF process. Moreover, overexpressed CHRFup-regulated TGF-b1, promoted myocardial cell apoptosis,and reversed VAL’s cardiac protective effect, while interferenceof CHRF (si-CHRF) did the opposite. Down-regulationof CHRF reversed the increased expression of TGFb1and the downstream proteins induced by pcDNA-TGFb1in HL-1 cells, while overexpression of CHRF reversedthe VAL’s cardiac protective effect in vivo. In conclusion,VAL regulates TGF-b pathways through lncRNA CHRF toimprove DOX-induced HF.