Design, analysis, and control of a cable-driven parallel platform with a pneumatic muscle active support

Dieser Beitrag ist mit Zustimmung des Rechteinhabers aufgrund einer (DFG geförderten) Allianz- bzw. Nationallizenz frei zugänglich.This publication is with permission of the rights owner freely accessible due to an Alliance licence and a national licence (funded by the DFG, German Research Foundation) respectively.The neck is an important part of the body that connects the head to the torso, supporting the weight and generating the movement of the head. In this paper, a cable-driven parallel platform with a pneumatic muscle active support (CPPPMS) is presented for imitating human necks, where cable actuators imitate neck muscles and a pneumatic muscle actuator imitates spinal muscles, respectively. Analyzing the stiffness of the mechanism is carried out based on screw theory, and this mechanism is optimized according to the stiffness characteristics. While taking the dynamics of the pneumatic muscle active support into consideration as well as the cable dynamics and the dynamics of the Up-platform, a dynamic modeling approach to the CPPPMS is established. In order to overcome the flexibility and uncertainties amid the dynamic model, a sliding mode controller is investigated for trajectory tracking, and the stability of the control system is verified by a Lyapunov function. Moreover, a PD controller is proposed for a comparative study. The results of the simulation indicate that the sliding mode controller is more effective than the PD controller for the CPPPMS, and the CPPPMS provides feasible performances for operations under the sliding mode control

Integrated evaluation of air flow and gas dispersion for underground station safety strategies based on subway climatology

PhD ThesisRail underground systems are seen as a way to overcome traffic congestion in city environments. Many new subways are being built in China and developing countries. Recent studies have however shown that the ventilation of subway systems is poorly understood. There is significant danger to life if a fire occurs or toxins such as chemical or biological agents are released in a subway. Understanding the air flow inside a subway and how this is affected by the local environment is key in establishing effective evacuation strategies. A series of tracer gas experiments conducted as part of this research have been carried out. To expand the subway climatology from an experimental framework into a virtual and simulation environment, 3D Computational Fluid Dynamic models have been developed, which include the simulation of local microclimate and air movement inside the station respectively. The station CFD model has allowed the analysis of the air flow inside the station under the prevailing external weather condition. Results show promising links between external climatic factors, the subway climatology and the ability to predict the dispersal of smoke/toxins. The local weather pattern has a large influence on the background airflow inside a station and dominated the flow direction at station exits which is been used to evaluate the efficiency of pedestrian evacuation and also determine the safer evacuation route and exit. The possibilities of integrating these findings will allow for a more holistic safety assessment to be carried out that could reduce the loss of life or mitigate harmful effects on public health. It also fills a knowledge gap in design guidelines from a safety perspective underground station construction and ventilation

Geography and similarity of regional cuisines in China

Food occupies a central position in every culture and it is therefore of great interest to understand the evolution of food culture. The advent of the World Wide Web and online recipe repositories has begun to provide unprecedented opportunities for data-driven, quantitative study of food culture. Here we harness an online database documenting recipes from various Chinese regional cuisines and investigate the similarity of regional cuisines in terms of geography and climate. We found that the geographical proximity, rather than climate proximity is a crucial factor that determines the similarity of regional cuisines. We develop a model of regional cuisine evolution that provides helpful clues to understand the evolution of cuisines and cultures.Comment: 13 pages, 11 figures and 2 table

Polycystic ovary syndrome in patients with epilepsy: A study in 102 Chinese women

AbstractPurposeThe incidence of polycystic ovary syndrome (PCOS) increases in women with epilepsy (WWE), which appears to vary with ethnicity. This study was conducted to determine the incidence and risk factors of PCOS in Chinese WWE.MethodsThe study was carried out in 102 of 139 Chinese WWE at reproductive ages, with 32 receiving valproic acid (VPA), 40 receiving other antiepileptic drugs (AEDs), and 30 without AEDs therapy. PCOS was defined as having 2 or more of the following components: polycystic ovaries, hyperandrogenism, and amenorrhoea or oligomenorrhoea (a/oligomenorrhoea).ResultsOne or more isolated components of PCOS were found in 56 (54.9%) patients, with 29 (28.4%) having polycystic ovaries, 20 (19.6%) with a/oligomenorrhea, 7 (6.9%) with hyperandrogenism, and 13 (12.7%) with defined PCOS. Their average age at the start of seizure was 13.8±6.5years, younger than that of patients without these disorders (16.9±8.6years, p<0.05). VPA therapy increased the incidence of PCOS (11/32, 34.4%), in addition to increased blood levels of testosterone and luteinizing hormone (LH) as well as LH to FSH (follicle-stimulating hormone) ratio. No significant relationship was found between the incidence of PCOS and the type, duration, or frequency of seizures in these WWE.ConclusionThere is an increased incidence of PCOS in Chinese WWE at reproductive ages, by more than 2 times of that in the general population. Risk factors include seizures starting at a young age and VPA therapy

Based on the concept of translational medicine in the exploration and practice of teaching reform of pathophysiology

Objective: To investigate the application of the teaching mode in pathophysiology, based on the thought of translational medicine and combined basic medicine with clinical medicine. Methods: Choosing the five-year period medical undergraduates in our university, who were enrolled in the year of 2012, through developing comprehensive case-based teaching (CCBT) in large class teaching, having case-problem based learning (CPBL) in small class teaching, and carrying out comprehensive open experiments during the experiment teaching, the pathophysiology teachers participated in clinical (internal medicine) practice, to apply the concept of translational medicine into Pathophysiology teaching reform, setting up a teaching mode, which was based on the thought of translational medicine and combined basic medicine with clinical medicine. Results: This model of education further stimulated students’ interest in study, enlightened their creative thought, enhanced the initiative of students greatly, raised students' ability to think and solve problems independently. At the same time, it improved the teachers' teaching level, and made this curriculum serving as a bridge between basic medicine and clinical medicine. Conclusion: The pedagogical reform of pathophysiology, which was based on the idea of translational medicine, improved educational effect and was worthy to be applied further

The Transformation of Urban Vegetable Retail in China: Wet Markets, Supermarkets, and Informal Markets in Shanghai

Singapore Management University Office of ResearchThis research is supported by a research grant from the Singapore Management University’s Office of Research to the first author. We thank Professor JIANG Changjian of Fudan University and Ms. Lu Zhihua of Wujiaochang Town Government for facilitating the fieldwork. An earlier version of the paper was presented at the Sixth Annual Workshop of the Asian Network of Scholars of Local China (ANSLoC). We are grateful to participants of the workshop, including Professors Jae Ho Chung, Tse-Kang Leng, John DONALDSON, Hongyi Lai, Phil Hsu, Wai-Keung Chung, Eric Mobrand, and James Tang, for their valuable comments and suggestions. The authors are solely responsible for any errors.</p