Shun-Neng Yang

Charge scheduling of electric vehicles in highways

Abstract Today, charging stations (CSs) for electric vehicles (EVs) are much less popular than gas stations. Therefore, searching and selecting CSs is an important issue for the drivers of EVs. This paper investigates the EV charging problem. We propose two types of CS-selection algorithms. The first type only utilizes local information of an EV. The second type utilizes the global information obtained through interactions between the EVs and a Global CS-selection (GCS) server through the mobile telecommunications network. Our study indicates that by using the global information (specifically the workload status of each CS), the EVs can be effectively charged with short waiting times at the CSs.

Operating electric taxi fleets: A new dispatching strategy with charging plans

In this paper, we propose a dispatching strategy with charging plans upon the client requests for a commercial fleet of pure electric taxis. To boost the green industry, promoting the development of electrical vehicles is one of the most important policies of many governments. In a new scenario that the commercial taxi fleets run electrical vehicles as the main transportation, traditional dispatching policies for general gasoline taxis are no longer effective. It is because those policies do not need to consider the newly generated issues for the electrical vehicles such as the endurance and the related charging problems when dispatching them. In addition, taxi drivers may doubt whether their working hours would be occupied by the possibly long waiting time of power recharging and thus decrease the chances to carry clients. To overcome the above issues, this paper proposes a new dispatching policy in consideration of the taxi demand, the remaining power of electrical taxis, and the availability of battery charging/switching stations in order to lower the waiting time of power recharging and thus increase the workable hours for taxi drivers. Simulation results show that our dispatching strategy can effectively reduce the waiting time for charging and increase the chances of taking clients compared to some random dispatching strategy.

Improving Handover and Drop-off Performance on High-Speed Trains With Multi-RAT

Provisioning commercial mobile telecommunications service on a high-speed train (HST) faces several challenges. In particular, when an HST quickly passes through the radio coverage of the base stations, frequent handovers may result in serious communication interruption. Methods such as the hierarchical two-hop network and the seamless dual-link handover scheme were proposed to address these challenges. This paper proposes the multiple radio access technology (multi-RAT) to resolve the HST handover issue, which allows the HST to simultaneously connect to two or more heterogeneous mobile networks (e.g., the Universal Mobile Telecommunications System and Long Term Evolution). With this approach, the handover process can be improved by keeping multiple heterogeneous network links of the HST at the same time and maintaining the connection through one link during the handover process of the other link. We show that multi-RAT can effectively enhance HST communications by reducing the impact of handover failure. This approach can work together with other solutions such as the dual-link scheme to further enhance the performance of the HST communications.

Mobile charging information management for smart grid networks

a b s t r a c t With todays electric charging technology, charging time of an electric vehicle (EV) is much longer than that for a gasoline vehicle, and therefore the queueing effect at an EV charging station (CS) may be serious. That is, when an EV arrives at an overloaded CS, it is likely that the EV will wait for a long time before it is charged. This paper investigates the waiting problem for EV charging. We propose a Mobile CS (MCS) management system to dynamically distribute charging pole support that reduces the waiting times of EVs incurred in a fixed CS. A Mobile Charging Information Management System (MC-IMS) is presented to describe the execution flow of the MCS service. Simulation experiments are conducted to investigate the waiting time performance for the proposed mechanism. Our study indicates that the MCS-based MC-IMS provides effective EV charging with short waiting times.

A multi-RAT bandwidth aggregation mechanism with software-defined networking

The population of smart mobile devices drives the mobile traffic growth rapidly. To deal with the traffic explosion, heterogeneous radio network integration is considered as a cost-effective solution for mobile operators to reduce network congestion. With the coverage overlapping of various wireless networks (e.g., LTE and Wi-Fi), we can use multiple networks to transfer different services simultaneously. In this paper, we integrate the multiple radio access technology (multi-RAT) with software-defined networking (SDN) to make the multi-RAT network more programmable, dynamically manageable and adaptable. The analytic model and performance evaluation show that our mechanism can significantly reduce the response times when the multi-RAT network traffic is unbalanced, where the throughput degradation of adapting our mechanism is 4.15% on average.

A Multi-link Mechanism for Heterogeneous Radio Networks

Nowadays, smart mobile devices drive the mobile traffic growth rapidly. Most smart mobile devices are equipped with multiple radio network interfaces, such as High Speed Packet Access (HSPA), Long Term Evolution (LTE), and Wi-Fi. Therefore, integration of multiple networks is a viable solution to fulfill traffic offloading and the Quality-of-Service (QoS) requirement of data usage for mobile users. In this paper, we propose a multi-link mechanism to handle the radio network selection and switching between LTE and Wi-Fi networks. A Multi-Link Adaptor (MLA) and a Multi-Connection Manager (MCM) are proposed for the User Equipment (UE) and the core network, respectively, to handle the multi-link mechanism. The applications executed in the UEs do not need to be modified under the proposed approach. The MLA maintains a QoS class table and a routing table for the network selection procedure and uses the GPRS Tunneling Protocol-Control plane (GTP-C) control messages to execute network switching. In the future, we will measure the throughput of the multi-link network and the switch delay between the heterogeneous radio networks.

Charge Scheduling of Electric Vehicles in Highways through Mobile Computing

Today, charging stations (CSs) for electric vehicles (EVs) are much less popular than gas stations. Therefore, searching and selecting CSs is an important issue for the drivers of EVs. This paper investigates the EV charging problem. We propose two types of CS-selection algorithms. The first type only utilizes local information of an EV. The second type utilizes the global information obtained from mobile computing. Specifically, the EVs interact with a Global CS-selection (GCS) server through the mobile telecommunications network. Our study indicates that by using the global information (specifically the workload status of each CS), the EVs can be effectively charged with short waiting times at the CSs.

Mobile Charging Station service in smart grid networks

Today, charging time of an electric vehicle (EV) is much longer than that for a gasoline vehicle. If an EV arrives at an overloaded charging station, it will wait for a long time. This paper investigates the waiting problem for EV charging. We propose a Mobile Charging Station (MCS) service to reduce the waiting times of EVs incurred in fixed charging station. A dispatching algorithm is presented to describe the execution flow of the MCS service. Simulation experiments are conducted to investigate the waiting time performance for the proposed algorithm. Our study indicates that by using the MCS service, the EVs can be effectively charged with short waiting times.