Effect of pulsed power on particle matter in diesel engine exhaust using a DBD plasma reactor

Nonthermal plasma (NTP) treatment of exhaust gas is a promising technology for both nitrogen oxides (NOX) and particulate matter (PM) reduction by introducing plasma into the exhaust gases. This paper considers the effect of NTP on PM mass reduction, PM size distribution, and PM removal efficiency. The experiments are performed on real exhaust gases from a diesel engine. The NTP is generated by applying high-voltage pulses using a pulsed power supply across a dielectric barrier discharge (DBD) reactor. The effects of the applied high-voltage pulses up to 19.44 kVpp with repetition rate of 10 kHz are investigated. In this paper, it is shown that the PM removal and PM size distribution need to be considered both together, as it is possible to achieve high PM removal efficiency with undesirable increase in the number of small particles. Regarding these two important factors, in this paper, 17 kVpp voltage level is determined to be an optimum point for the given configuration. Moreover, particles deposition on the surface of the DBD reactor is found to be a significant phenomenon, which should be considered in all plasma PM removal tests

Impact of local emergency demand response programs on the operation of electricity and gas systems

With increasing attention to climate change, the penetration level of renewable energy sources (RES) in the electricity network is increasing. Due to the intermittency of RES, gas-fired power plants could play a significant role in backing up the RES in order to maintain the supply–demand balance. As a result, the interaction between gas and power networks are significantly increasing. On the other hand, due to the increase in peak demand (e.g., electrification of heat), network operators are willing to execute demand response programs (DRPs) to improve congestion management and reduce costs. In this context, modeling and optimal implementation of DRPs in proportion to the demand is one of the main issues for gas and power network operators. In this paper, an emergency demand response program (EDRP) is implemented locally to reduce the congestion of transmission lines and gas pipelines more efficiently. Additionally, the effects of optimal implementation of local emergency demand response program (LEDRP) in gas and power networks using linear and non-linear economic models (power, exponential and logarithmic) for EDRP in terms of cost and line congestion and risk of unserved demand are investigated. The most reliable demand response model is the approach that has the least difference between the estimated demand and the actual demand. Furthermore, the role of the LEDRP in the case of hydrogen injection instead of natural gas in the gas infrastructure is investigated. The optimal incentives for each bus or node are determined based on the power transfer distribution factor, gas transfer distribution factor, available electricity or gas transmission capability, and combination of unit commitment with the LEDRP in the integrated operation of these networks. According to the results, implementing the LEDRP in gas and power networks reduces the total operation cost up to 11% and could facilitate hydrogen injection to the network. The proposed hybrid model is implemented on a 24-bus IEEE electricity network and a 15-bus gas network to quantify the role and value of different LEDRP models

A Novel Dual Factor Fuzzy Time Series Forecasting based on new Fuzzy sets and Interval Definition by Evolution Strategies

This paper proposes a new dual factor time-invariant fuzzy time series method that is capable of forecasting stock marketPrice Index. The proposed approach uses a new fuzzy logic relationship definition. According to the utilized membershipdegrees used to define the fuzzy relationships, each datum may belong to two distinct intervals rather than only one interval.This assumption, which has not been considered in the other studies, contributes to better forecasting results. In addition, anappropriate meta-heuristic algorithm for continuous solution schemes, namely evolution strategies (ES), is utilized to identifythe appropriate interval lengths. The proposed approach has been tested on TAIFEX index. The computational results showedthat the proposed approach outperforms the former studies

Performance evaluation of non-thermal plasma on particulate matter, ozone and CO2 correlation for diesel exhaust emission reduction

This study is seeking to investigate the effect of non-thermal plasma technology in the abatement of particulate matter (PM) from the actual diesel exhaust. Ozone (O3) strongly promotes PM oxidation, the main product of which is carbon dioxide (CO2). PM oxidation into the less harmful product (CO2) is the main objective whiles the correlation between PM, O3 and CO2 is considered. A dielectric barrier discharge reactor has been designed with pulsed power technology to produce plasma inside the diesel exhaust. To characterise the system under varied conditions, a range of applied voltages from 11 kVPP to 21kVPP at repetition rates of 2.5, 5, 7.5 and 10 kHz, have been experimentally investigated. The results show that by increasing the applied voltage and repetition rate, higher discharge power and CO2 dissociation can be achieved. The PM removal efficiency of more than 50% has been obtained during the experiments and high concentrations of ozone on the order of a few hundreds of ppm have been observed at high discharge powers. Furthermore, O3, CO2 and PM concentrations at different plasma states have been analysed for time dependence. Based on this analysis, an inverse relationship between ozone concentration and PM removal has been found and the role of ozone in PM removal in plasma treatment of diesel exhaust has been highlighted

Biodiversity of genus Orius (Hemiptera: Anthocoridae) in various climate regions and seasons of Kohgiloyeh and Boyerahmad province and evaluation of agro-ecosystem effects on their biodiversity

The members of genus Orius are known as natural enemies of many of plant pests in the world. We studied the fauna and biodiversity of the family Anthocoridae bugs in different environmental conditions of Kohgiloyeh and Boyrahmad province of Iran. Sampling took place in three climates and from three ecosystems (gardens, farms and virgin uncultivated lands) throught three replicationsevery other week. Species were identified based on male genitalia, and the biodiversity study was done using Shannon-Wiener dominance index through SDR software. The species Orius albidipennis (Reuter), O. niger (Wolff), O. laevigatus (Fiber),O. pallidicornis (Reuter),O. vicinus (Ribaut), O. horvati(Reuter) were identfied. The results showed that O. albidipennis was the dominant species in tropical climate and O. niger was the dominant species in cold climate. The Shannon-Wiener indices of tropical, moderate and cool climates were 1.245, 1.233, and 0.9896 respectively. Biodiversity of Orius spp in non manipulated ecosystems were significantly higher than manipulated (agricultural) ecosystems. Therefore biodiversities of the natural enemies were significantly affected by climate and ecosystem conditions.Regarding the side effects of ecosystem manipulating treatments on the biodiversity of the predatory bugs, some conservative treatments such as multi-cropping, rgeen islands of weed could enhance biodiversity and efficiency of predators

Embolization of immediate release transcatheter patch for atrial septal defect occlusion: The causes and the pitfalls to avoid

We report embolization of a bioabsorbable immediate-release patch for closure of atrial septal defect into left atrium with forward movement into and out of the mitral valve during each cardiac cycle. The dislodged device was ultimately explanted by a surgical operation and the defect was closed. We discuss causes and recommend tips to prevent such a serious potential complication. We also suggest some modifications to the device for making it more safe and effective

The Incremental Cooperative Design of Preventive Healthcare Networks

This document is the Accepted Manuscript version of the following article: Soheil Davari, 'The incremental cooperative design of preventive healthcare networks', Annals of Operations Research, first published online 27 June 2017. Under embargo. Embargo end date: 27 June 2018. The final publication is available at Springer via http://dx.doi.org/10.1007/s10479-017-2569-1.In the Preventive Healthcare Network Design Problem (PHNDP), one seeks to locate facilities in a way that the uptake of services is maximised given certain constraints such as congestion considerations. We introduce the incremental and cooperative version of the problem, IC-PHNDP for short, in which facilities are added incrementally to the network (one at a time), contributing to the service levels. We first develop a general non-linear model of this problem and then present a method to make it linear. As the problem is of a combinatorial nature, an efficient Variable Neighbourhood Search (VNS) algorithm is proposed to solve it. In order to gain insight into the problem, the computational studies were performed with randomly generated instances of different settings. Results clearly show that VNS performs well in solving IC-PHNDP with errors not more than 1.54%.Peer reviewe