The kinetics of degradation of methyl tert-butyl ether (MTBE) by ultrasonic irradiation in the presence of ozone as functions of applied frequencies and applied power are investigated. Experiments are performed over the frequency range of 205-1078 kHz. The higher overall reaction rates are observed at 358 and 618 kHz and then at 205 and 1078 kHz. The observed pseudo-first-order rate constant, k 0 , for MTBE degradation increases with increasing power density up to 250 W L -1 . A linear dependence of the first-order rate constant, k O3 , for the simultaneous degradation of O 3 on power density is also observed. Naturally occurring organic matter (NOM) is shown to have a negligible effect on observed reaction rates.

Oxidation of trichloroethylene (TCE) and tetrachloroethylene (PCE) with various dosages of ozone or ozone plus hydrogen peroxide was studied in laboratory experiments. The results show that hydrogen peroxide accelerates the oxidation of TCE and PCE by ozone. At peroxide‐to‐ozone dosage ratios of >0.7 (w/w), the process appears to be mass transfer limited. High levels of bicarbonate ion in the groundwater significantly decreased the efficiency of TCE and PCE removal by the ozone‐peroxide system, suggesting that softening prior to oxidation may improve the process.

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This article presents the results of a pilot‐scale evaluation of an advanced oxidation process that utilizes hydrogen peroxide and ozone. Treatment efficiency was determined as a function of the hydrogen peroxide‐to‐ozone dosage ratio, ozone dosage, and contact time. The ozone mass transfer characteristics of the process were also investigated. Comparison with other treatment technologies indicates that advanced oxidation can be a cost‐effective treatment process for controlling the common chlorinated organics found in groundwater.

Abstract-People experience a variety of 3D visual programs, such as 3D cinema, 3D TV and 3D games, making it necessary to deploy reliable methodologies for predicting each viewer's subjective experience. We propose a new methodology that we call multimodal interactive continuous scoring of quality (MICSQ). MICSQ is composed of a device interaction process between the 3D display and a separate device (PC, tablet, etc.) used as an assessment tool, and a human interaction process between the subject(s) and the separate device. The scoring process is multimodal, using aural and tactile cues to help engage and focus the subject(s) on their tasks by enhancing neuroplasticity. Recorded human responses to 3D visualizations obtained via MICSQ correlate highly with measurements of spatial and temporal activity in the 3D video content. We have also found that 3D quality of experience (QoE) assessment results obtained using MICSQ are more reliable over a wide dynamic range of content than obtained by the conventional single stimulus continuous quality evaluation (SSCQE) protocol. Moreover, the wireless device interaction process makes it possible for multiple subjects to assess 3D QoE simultaneously in a large space such as a movie theater, at different viewing angles and distances. We conducted a series of interesting 3D experiments showing the accuracy and versatility of the new system, while yielding new findings on visual comfort in terms of disparity, motion and an interesting relation between the naturalness and depth of field (DOF) of a stereo camera.Index Terms-Multimodal interactive continuous scoring of quality (MICSQ), 3D quality of experience (QoE), subjective assessment, visual comfort evaluation, interactive continuous subjective quality assessment, empirical 3D distortion.

This paper investigates the fault-tolerance control of a multilevel cascaded NPC/H-bridge (CNHB) inverter. The fault-tolerance control method has been widely used for multilevel inverters, such as the neutral-point voltage-shifting control, which can operate for a certain period of time by compensating for the phase voltage of a faulty stack even if one stack is broken. Even though the three-phase equilibrium is maintained in the case of failure by using the conventional neutral-point voltage-shifting control, an imbalance in the output power occurs between each stack, which causes problems for maintenance and lifetime. Therefore, this paper proposes a fault-tolerance control that can maintain three-phase equilibrium in a case of stack failures and minimize power imbalances between the stacks. The problem of the conventional neutral-point voltage-shifting control is presented based on the output power. In addition, the power imbalance is improved by performing selective neutral-point voltage-shifting control according to the reference voltage range. To verify the principle and feasibility of the proposed neutral-point voltage-shifting control method, a simulation and an experiment are implemented with the CNHB inverter.

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