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Qianguo, China

Zhang Y.-Q.,Tarim University | Ding W.-C.,Lanzhou Jiaotong University
Zhendong yu Chongji/Journal of Vibration and Shock

Dry friction structures exist in many mechanical systems, their vibration behavior is a typical non-smooth dynamical. Here, a nonlinear vibration system with dry friction was taken as a piecewise-linear system, a method of getting analytical solutions to all stick-slip stages of the system was proposed, the model of 2-DOF dry friction vibration system was taken as an example, its dynamic responses were simulated numerically and its stick-slip vibration behaviors induced by dry friction were discussed. Source

Flow against Xingjian's oil and gas pipeline leakage and the pipe network sudden burst pipe to pipeline leakage flow for the application objects, Optimal pacing scheme is designed in pipeline leak monitoring. Based on the property of Markov chain for network data, a new estimator with particle filter is proposed for congestion control in this paper. In the context of a reconfigurable transport protocol framework, we propose a QoS aware Transport Protocol (QSTP), specifically designed to operate over QoS (Quality of Service) enabled networks with bandwidth guarantee. The proposed scheme can adaptively adjust the network rate in real -time, so that it can efficiently avoid the traffic congestion. It proposes a Link Layer Adaptive Pacing (LLAP) scheme that adaptively controls the offered load into the network. The algorithms actively probe the underlay network and compute virtual multicast trees by dynamically selecting the least loaded available paths on the overlay network. The low computational complexity of the proposed algorithms leads to time and resource saving, as shown through extensive experiments. The Simulation results show that Network congestion avoidance strategy with optimal pacing scheme can efficiently improve the bandwidth utilization, Transmission Control Protocol (TCP) friendliness and reduce the packet drop rate in Pipeline Flux Leak Monitoring networks. Flood flow identified by the National Centre for testing: discussion group first proposed the use of particle filters to solve the new model can estimate the network congestion control problem. The results are sound, stable performance, efficiency 29%. Adaptive algorithm using the model proposed optimization scheme, to achieve accurate positioning of the leak, 0.05% measurement accuracy, positioning accuracy is improved 32%, more than 17% of the nodes in a more reliable routing path, reliable routing path of increase of 40%. © 2011 ACADEMY PUBLISHER. Source

Shuaixu L.,Tarim University
RISTI - Revista Iberica de Sistemas e Tecnologias de Informacao

Objective: The method of computer multimedia CAI courseware to be used in the teaching of table tennis in college students and explore the teaching effect of multimedia teaching to improve the teaching effect of table tennis. Method: Questionnaire survey, comparative experiment, mathematical statistics, logical analysis. Process: Through the experimental group and the control group of students in the average score of the comparison, a mathematical analysis; A questionnaire survey was conducted on the students in the experimental group. Result & Analysis: There is significant difference between subject test scores and learning attitude of students in experimental group and control group, and most of the students think that the effect of multimedia teaching is good and willing to accept it. Result: Multimedia CAI courseware can effectively improve the teaching effect of table tennis technology and worthy to be promoted. Source

Xie W.,North University of China | Zhang X.,North University of China | Wang T.,North University of China | Hu J.,Tarim University
Journal of Ethnopharmacology

Ethnopharmacological relevance: Apocynum venetum L. (Apocynaceae, Luobuma) has a long history as a Chinese traditional medicine with uses to calm the liver, soothe the nerves, dissipate heat, and promote diuresis. Recently, Luobuma tea has been commercialized as a sedative and anti-aging supplement that has become increasingly popular in North American and East Asian health food markets. Aims of the review: The aim of this review is to provide an up-to-date and comprehensive overview of the botany, chemical constituents, traditional uses, pharmacological activities and safety aspects of Apocynum venetum in order to assess its ethnopharmacological use and to explore its therapeutic potentials and future opportunities for research. Background and methods: The accessible literature on Apocynum venetum written in English, Chinese and Japanese were collected and analyzed. The literatures included ancient Chinese herbal classics, pharmacopoeias and articles that included in Pubmed, Web of Science, Google Scholar and Wanfang. Key findings: Modern pharmacological studies demonstrated that Apocynum venetum possess wide pharmacological activities that include antihypertensive, cardiotonic, hepatoprotective, antioxidant, lipid-lowering, antidepressant and anxiolytic effects, which can be explained by the presence of various flavonoid compounds in this plant. The traditional (Lop Nor region) use of Apocynum venetum with tobacco as an agent to detoxify nicotine may receive interest as a possible therapeutic option to detoxify the body from smoking. Based on animal studies and clinical trials, Apocynum venetum causes no severe side effects, even in a stable daily dosage (50 mg/person/day) for more than three years. Conclusions: Apocynum venetum potentially has therapeutic potential in the prevention and treatment for the cardiovascular and neurological diseases, especially for high blood pressure, high cholesterol, neurasthenia, depression and anxiety. Further investigations are needed to explore individual bioactive compounds responsible for these in vitro and in vivo pharmacological effects and the mode of actions. Further safety assessments and clinical trials should be performed before it can be integrated into medicinal practices. © 2012 Elsevier Ireland Ltd. All rights reserved. Source

Du Z.,Northwest University, China | Du Z.,Tarim University
Natural Product Communications

A facile total synthesis of the bisabolane sesquiterpene, xanthorrhizol (1), has been achieved in 6 steps, in 48% overall yield. The starting material was 3-methoxy-4-methyl-phenoacetone (7), and a Claisen-Johnson rearrangement was used as the key step to construct the skeleton of the target molecule. Source

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