Admission Control Scheme for Handover Service in High-Speed Train Communication System

Admission control in high-speed train communication system is quite different from admission control in traditional cellular networks. Conventional admission control strategies cannot be directly applied to this special communication scenario. In this paper, the problem of admission control for handover service is investigated in high-speed train communication environment. An admission control scheme considering bit error rate(BER)and bandwidth borrowing strategy is proposed. On the basis of admission control decision rule taking BER into account, a part of bandwidth obtained by compressing variable rate service in the networks is provided for handover services. The admission control scheme can admit handover services as more as possible while it guarantees the lowest data rate of different services in the networks. Simulation results show that the proposed admission control scheme has a better performance than existing admission control schemes.

Nurses’ movements within and between various paths when improving their communication skills—An evaluation of validation method training

Aims and objectives: To explore any changes in nurses’ skills at communicating with residents with dementia disease when using the validation method, as observed in one-to-one videotaped conversations. Background: Communication difficulties due to cognitive impairment among residents with dementia disease may complicate care situations. Training can improve nurses’ communication skills and increase care quality. The validation method aims to facilitate communication with residents with dementia disease through empathic and confirmatory approaches. Evaluations of the validation method have primarily focused on the residents’ perspective, and reports on nurses’ experiences are sparse. Improved communication and relationships with residents after validation method training have been described previously. Videotaped data could provide additional information about these earlier results. Design: A descriptive qualitative design. Methods: Eight nurses participated in a year of validation method training, including videotaped conversations with eleven residents. Videotapes with at least five months between the first and last recording were analysed and compared qualitatively. Results: The analysis revealed an overall pattern: nurses’ movements within and between various paths when improving their communication skills. This was based on three sub-patterns: from controlling communication towards developing attentiveness in communication, from ambiguous communication towards developing coherence in communication, and from being open and attentive towards having a refined attuned communication. Conclusions: All nurses developed their communication skills during the programme, albeit to different degrees. The findings are in congruence with the experiences described by nurses, and so it is reasonable to believe that the programme helped to improve the nurses’ skills in communicating with residents with dementia disease. Relevance to clinical practice: A validation method training programme could give nurses the possibility to develop their skills in communicating with residents with dementia disease.

Modeling research of train tracing based on UML sequence diagram and UPPAAL

The zone control subsystem is a real-time control system,which requests the correctness of the control process.Train tracing scene is an important function of the zone controller(ZC)in the communication based train control(CBTC)system.In the process of deep development and design,to ensure the safety of the system,the system needs to be modeled,simulated and verified to discover the system design flaws.Unified modeling language(UML)is combined with timed automata,and timed automata network models of train-filter and train tracing demarcation-point are established.At the same time,the verification tool of UPPAAL is applied to simulate the system,and verify the requirements of performance and function of system.The results show that the function of train tracing demaraction-point meets the requirements of system safety and limited activity.Therefore,the method is feasible and can be applied to the modeling and verification of other scenes of train control system.

Train crossing modeling based on measurements and best numerical approximation in subway tunnels

Communication based train control systems （CBTC） must work even in the worst situation-- train crossing. This paper models the propagation characteristics in one of the most common and piv- otal scenarios--train crossing in subway tunnels which is rarely mentioned in previous publications. Firstly, measurements for train crossing scenario at 2.4 GHz in a real subway line in Madrid have been made. The field measurement is the most reliable way to reveal the propagation characteristics involving shadowing effect and fast fading. Moreover, to precisely describe the fast fading distribu- tion and eliminate the inevitable weak points of traditional fitting way, a best numerical approxima- tion method using Legendre orthogonal polynomials has been proposed. Comparisons show that this method works better and is of greater physical significance. Finally, a complete statistical model is given and all the coefficients can be applied by system designers for the link and system level simu- lations.

High-Speed EMU TCMS Design and LCC Technology Research

This paper introduces the high-speed electrical multiple unit （EMO） life cycle, including the design, manufacturing, testing, and maintenance stages. It also presents the train control and monitoring system （TCMS） software development platform, the TCMS testing and verification bench, the EMU driving simulation platform, and the EMU remote data transmittal and maintenance platform. All these platforms and benches combined together make up the EMU life cycle cost （LCC） system. Each platform facilitates EMU LCC management and is an important part of the system.

Future 5G-Oriented System for Urban Rail Transit:Opportunities and Challenges

As a development direction of urban rail transit system,the train autonomous circumambulate system(TACS)can operate in a safer,more efficient,and more economical mode.However,most urban rail transit systems transmit signals through industrial,scientific,and medical(ISM)frequency bands or narrow frequency bands,which cannot meet the requirements of TACS.As a promising solution,the 5th generation(5G)mobile communication provides more services for the future urban rail transit systems,and covers the shortages of exiting communication technologies in terms of capacity and reliability.In this paper,we first briefly review the research status of current train control system and introduce its limitations.Next,we propose a novel network architecture,and present new technologies and requirements of the proposed architecture for TACS.Some potential challenges are then discussed to give insights for further research of TACS.

AN INVESTIGATION OF COMMUNICATION STRATEGIES USED BY CHINESE NON-ENGLISH MAJOR POSTGRADUATES

This paper, through tape-recording students' conversations with native speakers, makes an attempt to examine the use of CSs by Chinese non-English major students at postgraduate level. The results show that the students are not competent in using CSs, which is easily seen in their heavy reliance on the L1-based strategies and appeal for assistance strategy rather than the more efficient and effective L2-based strategies. Inexperienced in oral communication and unaware of CSs, the students in general need awareness training in the use of CSs. Suggestions are then given as to how to conduct the training in terms of form, procedure and materials.

Probabilistic Modeling and Optimization of Real-Time Protocol for Multifunction Vehicle Bus

In this paper, we present the modeling and optimization of a Real-Time Protocol（RTP） used in Train Communication Networks（TCN）. In the proposed RTP, message arbitration is represented by a probabilistic model and the number of arbitration checks is minimized by using the probability of device activity. Our optimized protocol is fully compatible with the original standard and can thus be implemented easily. The experimental results demonstrate that the proposed algorithm can reduce the number of checks by about 50%, thus significantly enhancing bandwidth.