Estimating truncated hotel demand: A comparison of low computational cost forecasting methods

The aim of this thesis is to evaluate the effectiveness of six selected low computational cost hotel demand forecasting methods (SA, SMA, EMA, DEMA, BP and PU) in terms of restoring truncated demand data, and then identify a low-cost and easy to follow demand forecasting method that can be used by U.S. independent hotels. Obtaining revenue gains by applying demand forecasting techniques have been proved by many studies in hospitality and other related industries. However, few studies have focused on low computational forecasting methods\u27 comparison in hospitality field. For this reason, the author decided to test the performance of six selected demand forecasting techniques, with the aim of identifying an effective method for hotels operators constrained by financial resources and expertise. This thesis first simulates leisure and business real demand booking curves under a pre-decided increasing rate in each of three leisure/business ratio scenarios (1:3, 1:1, and 3:1). In the second stage, true demands are truncated in three cases. They are 1) capacity truncation, 2) 50% truncation of total business demand, and 3) 25% truncation of total business demand. And then, six selected forecasting methods are applied to the truncated demand. Finally, the forecasting accuracy for each method is evaluated in both statistical and economical models. The results of the experiment indicate that PU method outperform all the other selected methods and was proved to be the most effective forecasting method for U.S. independent hotels. Other new findings include that the data restoration accuracy ranged from a negative relationship with the business demand proportion of total bookings, and the higher the percentage the business bookings were truncated, the smaller the detruncation error occurs. The results also shows that the less the business booking was truncated; the more variable the forecasting error occurs. An interesting finding of this thesis is that in some specific circumstances, the results of statistical evaluation do not completely in accordance with economical evaluation results

INVESTIGATION OF RESISTIVE GEODESIC ACOUSTIC MODE IN THE EDGE OF STOR-M TOKAMAK

A new resistive Geodesic Acoustic Mode (GAM) theory is developed by two-fluids analysis and resistive gyro-kinetic formulation in this thesis. An analytical expression is obtained for the resistive GAM frequency. This theory suggests a large collision frequency will prohibit the parallel current in tokamak, which establishes the cross-field charge neutrality condition ∇·J⊥= 0 for the existence of GAM at the edge plasma of tokamak. Therefore, the resistive GAM theory provides a more plausible explanation to edge GAM phenomena. Various probe arrays are designed and installed in the STOR-M tokamak to search for the poloidal GAM phenomena. A series of experiments were conducted in the L-mode and RMP discharges. The FFT and wavelet analyses indicate the existence of GAM phenomena in STOR-M, and the observed GAM frequencies match the theoretical predication using the resistive GAM model

LocNet: Global localization in 3D point clouds for mobile vehicles

Global localization in 3D point clouds is a challenging problem of estimating the pose of vehicles without any prior knowledge. In this paper, a solution to this problem is presented by achieving place recognition and metric pose estimation in the global prior map. Specifically, we present a semi-handcrafted representation learning method for LiDAR point clouds using siamese LocNets, which states the place recognition problem to a similarity modeling problem. With the final learned representations by LocNet, a global localization framework with range-only observations is proposed. To demonstrate the performance and effectiveness of our global localization system, KITTI dataset is employed for comparison with other algorithms, and also on our long-time multi-session datasets for evaluation. The result shows that our system can achieve high accuracy.Comment: 6 pages, IV 2018 accepte