Data Mining - Concepts and Techniques.

An Introduction to MultiAgent Systems.

Despite hospitality and tourism researchers’ recent attempts on examining different aspects of online word-of-mouth [WOM], its impact on hotel sales remains largely unknown in the existing literature. To fill this void, we conduct a study to empirically investigate the impact of online consumer-generated reviews on hotel room sales. Utilizing data collected from the largest travel website in China, we develop a fixed effect log-linear regression model to assess the influence of online reviews on the number of hotel room bookings. Our results indicate a significant relationship between online consumer reviews and business performance of hotels.

The impact of online user reviews on hotel room sales [Summary]

The issue of renewable energy is becoming significant due to increasing power demand, instability of the rising oil prices and environmental problems. Among the various renewable energy sources, fuel cell is gaining more popularity due to their higher efficiency, cleanliness and cost-effective supply of power demanded by the consumers. This paper presents a comprehensive review of different fuel cell technologies with their working principle, advantages, disadvantages and suitability of applications for residential/grid-connected system, transportation, industries and commercial applications. Development of mathematical model of fuel cell required for simulation study is discussed. This paper also focuses on the necessity of a suitable power-conditioning unit required to interface the fuel cell system with standalone/grid applications.

A review on fuel cell technologies and power electronic interface

Electrifying transportation is a promising approach to alleviate the climate change issue. The adoption of electric vehicle into market has introduced significant impacts on various fields, especially the power grid. Various policies have been implemented to foster the electric vehicle deployment and the increasing trend of electric vehicle adoption in the recent years has been satisfying. The continual development of electric vehicle power train, battery and charger technologies have further improved the electric vehicle technologies for wider uptake. Despite the environmental and economical benefits, electric vehicles charging introduce negative impacts on the existing network operation. Appropriate charging management strategies can be implemented to cater for this issue. Furthermore, electric vehicle integration in the smart grid can bring many potential opportunities, especially from the perspective of vehicle-to-grid technology and as the solution for the renewable energy intermittency issue. This paper reviews the latest development in electric vehicle technologies, impacts of electric vehicle roll out and opportunities brought by electric vehicle deployment.

A review on the state-of-the-art technologies of electric vehicle, its impacts and prospects

Computer system reliability is conventionally modeled and analyzed using techniques such as fault tree analysis and reliability block diagrams (RBDs), which provide static representations of system reliability properties. A recent extension to RBDs, called dynamic RBDs (DRBD), defines a framework for modeling the dynamic reliability behavior of computer-based systems. However, analyzing a DRBD model in order to locate and identify design errors, such as a deadlock error or faulty state, is not trivial when done manually. A feasible approach to verifying it is to develop its formal model and then analyze it using programmatic methods. In this paper, we first define a reliability markup language that can be used to formally describe DRBD models. Then, we present an algorithm that automatically converts a DRBD model into a colored Petri net. We use a case study to illustrate the effectiveness of our approach and demonstrate how system properties of a DRBD model can be verified using an existing Petri net tool. Our formal modeling approach is compositional; thus, it provides a potential solution to automated verification of DRBD models.

/pdf/automated-modeling-of-dynamic-reliability-block-diagrams-2pvxfv03gi.pdf

Automated Modeling of Dynamic Reliability Block Diagrams Using Colored Petri Nets

This paper discusses the principle and electrical characteristics of the fuel cell, designs an innovative hybrid power system, and proposes a new DC/DC converter scheme to combine the fuel cell with the storage system. An effective converter scheme for the fuel cell is obtained by analyzing the high efficient topology as well as the phase shifted pulse-width modulation. Through comparing several different control modes of converters, a 75-kW prototype system is constructed, moreover, which steady-state operating characteristics are illustrated and discussed in detail. At last, experimental results are also shown to verify the proposed scheme.

Fuel cell power system and high power DC-DC converter

Most of the existing finite-control-set model predictive current control (FCS-MPCC) schemes for multi-phase motor suffer from heavy computational burden, inevitable low-order harmonic currents, and variable switching frequencies. Some virtual voltage vector (V3)-based FCS-MPCC schemes can effectively suppress harmonic current by zeroing the harmonic subspace voltage on average during one sampling period. However, they fail when the motor has a nonsinusoidal back electromotive force. In order to solve the aforementioned issues, this paper proposes a constant switching frequency multiple-vector-based FCS-MPCC scheme. Unlike the traditional FCS-MPCC schemes, the proposed scheme selects optimal V3s and their duty ratios in two orthogonal subspaces. Thus, it can simultaneously track the references in both orthogonal subspaces. In this approach, the optimal V3s and their duty ratios are directly obtained from the principle of deadbeat current control without time-consuming enumeration-based state predictions and cost function calculations. In addition, the obtained optimal V3s and their duty ratios are adopted to rearrange the pulse sequence to obtain constant switching frequency and can be simply synthesized by carrier-based pulsewidth modulation. Furthermore, a discrete time disturbance observer is designed to improve the robustness of the proposed FCS-MPCC against parameter mismatch. Finally, comparative experiments with traditional MPCC schemes for five-phase surface-mounted permanent magnet synchronous machine are carried out to verify the effectiveness of the proposed scheme.

A Constant Switching Frequency Multiple-Vector-Based Model Predictive Current Control of Five-Phase PMSM With Nonsinusoidal Back EMF

A new topology bi-directional Z-source inverter is proposed. It can overcome the uncontrollable and unstable limitations of the Z-source inverter in DCM mode. The operational principle, design guidelines of Z-source networks and power devices are provided. A DC clamp snubber circuit is developed to limit the voltage spike on power device. Power loss analysis and 3-D design for Z-source inverter system are presented. A prototype of 55 kVA bi-directional Z-source inverter is designed to verify the principle and performance of the proposed topology.

Analysis and design of Bi-directional Z-source inverter for electrical vehicles

https://www.cs.uic.edu/~shatz/papers/csr09.pdf

Haiping Xu

Papers

Automated Modeling of Dynamic Reliability Block Diagrams Using Colored Petri Nets

Fuel cell power system and high power DC-DC converter

A Constant Switching Frequency Multiple-Vector-Based Model Predictive Current Control of Five-Phase PMSM With Nonsinusoidal Back EMF

Analysis and design of Bi-directional Z-source inverter for electrical vehicles

Survey: Combating online in-auction fraud: Clues, techniques and challenges