DYNAMIC BEHAVIOR ANALYSIS FOR LANDING-GEAR WITH DIFFERENT TYPES OF DUAL-CHAMBER SHOCK-STRUTS

In this paper three types of dual- chamber shock- struts are considered in dynamic analyses of landing-gear behavior during impact and taxi. Their dynamic characteristics are compared with each other according to calculation results, and some conclusions are presented.It is very helpful for selecting a suitable type of dual-chamber shock-strut in landing-gear design.

Shrek:a dynamic object-oriented programming language

From a perspective of theoretical study, there are some faults in the models of the existing object-oriented programming languages. For example, C# does not support metaclasses, the primitive types of Java and C# are not objects, etc. So, this paper designs a programming language, Shrek, which integrates many language features and constructions in a compact and consistent model. The Shrek language is a class-based purely object-oriented language. It has a dynamical strong type system, and adopts a single-inheritance mechanism with Mixin as its complement. It has a consistent class instantiation and inheritance structure, and the ability of intercessive structural computational reflection, which enables it to support safe metaclass programming. It also supports multi-thread programming and automatic garbage collection, and enforces its expressive power by adopting a native method mechanism. The prototype system of the Shrek language is implemented and anticipated design goals are achieved.

Interesting Features of Three-Dimensional Discrete Lotka-Volterra Dynamics

Discrete Lotka-Volterra systems in one dimension (the logistic equation) and two dimensions have been studied extensively, revealing a wealth of complex dynamical regimes. We show that three-dimensional discrete Lotka-Volterra dynamical systems exhibit all of the dynamics of the lower dimensional systems and a great deal more. In fact and in particular, there are dynamical features including analogs of flip bifurcations, Neimark-Sacker bifurcations and chaotic strange attracting sets that are essentially three-dimensional. Among these are new generalizations of Neimark-Sacker bifurcations and novel chaotic strange attractors with distinctive candy cane type shapes. Several of these dynamical are investigated in detail using both analytical and simulation techniques.

OBSERVATION ON THE THERAPEUTIC EFFECT OF ACPUNCTURE COMBINED WITH MASSAGE FOR CERVICAL SPONDYLOSIS OF VERTEBRAL ARTERIAL TYPE BY USING TRANCRANIAL DOPPLYER ULTRASONOGRAPHY

To observe the effect of acupuncture combined with massage on blood flow velocity of the vertebro-basilar artery in cervical spondylosis of vertebral arterial type （CSVAT） patients. Methods： In the present study, methods of evidence-based medicine, triple-centers, single-blindness, randomization and control were used. A total of 100 cases of CSVAT patients were randomized into acupuncture plus massage （acu-massage） group （n = 38）, acupuncture group （n = 32） and massage group （n = 30）. Acupoints used were Fengchi （风池, GB 20）, cervical Jiaji （颈夹脊 EX-B 2）, Baihui （百会 GV 20）, and the methods of massage used were kneading-rolling, adhesion-separating and acupoint-digital pressing, topical digital pressing and rubbing, traction-extending and mild palm-rubbing. The treatment was conducted once daily, with 7 sessions being a therapeutic course and continuously for 2 courses. Changes of peak velocity （Vp）, end-diastolic velocity （Vd）, mean velocity （Vm） of blood flow of the vertebral artery （VA） and basilar artery （BA）, etc were detected before and after the treatment by using transcranial Doppler （TCD） ultrasonography. Resuits： After the treatment, the abnormally low Vp of both VA and BA in acu-massage, acupuncture and massage groups, Vm of VA in acu-massage and acupuncture groups, Vm of BA in acu-massage and massage groups, and Vd of VA and BA in the 3 groups all increased significantly in comparison with their own pretreatment（ P 〈 0.05, 0.01）, and the therapeutic effects of acu-massage group in the 3 indexes were significantly superior to those of acupuncture group and/or massage group （P 〈0.05, 0.01 ）. The abnormally increased Vp of VA in acu-massage and acupuncture groups, Vm of VA in the 3 groups, and Vd of VA in acu-massage and massage groups decreased obviously after the treatment in comparison with their own pretreatment （P 〈 0.05, 0.01）, and the therapeutic effects of acu-massage group were significantly superior to those of acupuncture and/or massage group in the 3 indexes of VA （P〈0.05, 0.01）. In addition, the abnormally increased Vp, Vm and Vd of BA in the 3 groups showed a similar tendency. No significant differences between acupuncture and massage groups in 3 indexes （ P 〉0.05）. Conclusion： The therapeutic effects of acupuncture plus massage is significantly superior to those of simple acupuncture and simple massage therapies in improving abnormal blood dynamics of vertebral and basilar arteries in CSVAT patients.

Application and realization of key technologies in China railway e-ticketing system

Purpose–With the yearly increase of mileage and passenger volume in China’s high-speed railway,the problems of traditional paper railway tickets have become increasingly prominent,including complexity of business handling process,low efficiency of ticket inspection and high cost of usage and management.This paper aims to make extensive references to successful experiences of electronic ticket applications both domestically and internationally.The research on key technologies and system implementation of railway electronic ticket with Chinese characteristics has been carried out.Design/methodology/approach–Research in key technologies is conducted including synchronization technique in distributed heterogeneous database system,the grid-oriented passenger service record(PSR)data storage model,efficient access to massive PSR data under high concurrency condition,the linkage between face recognition service platforms and various terminals in large scenarios,and two-factor authentication of the e-ticket identification code based on the key and the user identity information.Focusing on the key technologies and architecture the of existing ticketing system,multiple service resources are expanded and developed such as electronic ticket clusters,PSR clusters,face recognition clusters and electronic ticket identification code clusters.Findings–The proportion of paper ticket printed has dropped to 20%,saving more than 2 billion tickets annually since the launch of the application of E-ticketing nationwide.The average time for passengers to pass through the automatic ticket gates has decreased from 3 seconds to 1.3 seconds,significantly improving the efficiency of passenger transport organization.Meanwhile,problems of paper ticket counterfeiting,reselling and loss have been generally eliminated.Originality/value–E-ticketing has laid a technical foundation for the further development of railway passenger transport services in the direction of digitalization and intelligence.

PMD compensation based on a new type dynamic first-order PMD compensator

A dynamic first-order polarization mode dispersion （PMD） compensator based on garnet and yttrium vanadate crystal has been proposed and implemented. Consisting of a differential group delay （DGD） generator and a Faraday rotator （FR）, this PMD compensator has only two degrees of freedom. Feedback control and compensation algorithm are both very simple. Experimental results reveal the compensator behaviors to be excellent for PMD compensation in 40-Gb/s optical time domain multiplexing （OTDM） system.

NUMERICAL ANALYSIS OF THE DYNAMICAL BEHAVIOR OF THE EQUATION OF J-J TYPE

In this paper, we have analysed the dynamical behavior of the Josephson Junction equation bynumerical computation and the theory of dynamical systems. As 0<β<2:1+ε, and ρis not sufficientlylarge, we observed the intermittent chaotic behavior and the period-doubling chaotic behavior in whichpeople are very interested recently. This implies the for some β(0<β<2:1+ε), the dynamicalbehavior of the J-J equation is rather complex.

Spatiotemporal dynamics in a network composed of neurons with different excitabilities and excitatory coupling

Spiral waves have been observed in the biological experiments on rat cortex perfused with drugs which can block inhibitory synapse and switch neuron excitability from type II to type I. To simulate the spiral waves observed in the experiment, the spatiotemporal patterns are investigated in a network composed of neurons with type I and II excitabilities and excitatory coupling. Spiral waves emerge when the percentage(p) of neurons with type I excitability in the network is at middle levels, which is dependent on the coupling strength. Compared with other spatial patterns which appear at different p values, spiral waves exhibit optimal spatial correlation at a certain spatial frequency, implying the occurrence of spatial coherence resonance-like phenomenon. Some dynamical characteristics of the network such as mean firing frequency and synchronous degree can be well interpreted with distinct properties between type I excitability and type II excitability. The results not only identify dynamics of spiral waves in neuronal networks composed of neurons with different excitabilities, but also are helpful to understanding the emergence of spiral waves observed in the biological experiment.

Multiply Kink and Anti-Kink Solutions for a Coupled Camassa–Holm Type Equation

This article amis at revealing dynamical behavior of a coupled Camassa–Holm type equation, which was proposed by Geng and Wang based on a 4×4 matrix spectral problem with two potentials. Its kink and anti-kink solutions are presented explicitly. In particular, some exact multi-kink and anti-kink wave solutions are discussed and under some conditions, the kink and anti-kinks look like hat-shape solitons. The dynamic characters of the obtained solutions are investigated by figures. The method used in this paper can be widely applied to looking for the multi-kinks for Camassa–Holm type equations possessing cubic nonlinearity.