31 research outputs found
Emission of Polychlorinated Dibenzo-p-Dioxins (PCDDs) and Polychlorinated Dibenzofurans (PCDFs) from Underfiring System of Coke Oven Battery
A coke oven battery is not considered as a significant source of PCDDs/PCDFs emissions; however, due to small amounts of chlorine in coal dioxins, dibenzofurans may be formed. The paper presents the attempts to determine the level of emission of PCDDs/PCDFs from the COB underfiring system and to confront the obtained results with the calculations based on the mass balance of chlorine in the coking process and reactions of both chlorophenols formation and PCDDs and PCDFs formation from mono- and polychlorophenols. There were PCDDs/PCDFs concentrations measured in flue gases from the underfiring system of two COBs at a Polish coking plant. The measurements included both an old and a new battery. The obtained concentrations of PCDDs/PCDFs were lower than reported in the literature (0.5-1.7 ng I-TEQ/tcoke), while the results for old COB were on average 3 times higher than for the new one. It was found that PCDD/F emission from COB underfiring system is insignificant and that PCDDs/PCDFs formation during coal coking should consider the mechanisms of their formation from mono- and polychlorophenols, as well as the influence of process parameters on the synthesis
Error Potentials for Brain-Computer Interfaces
The idea to use EEG correlates of errors to correct or reinforce BCI operation has been proposed over a decade ago. Since then a body of evidence has corroborated this approach. In this paper we give an overview of our recent work exploring the possibilities of error-potential applications, involving removing constraints of laboratory paradigms to increase “real-life” validity, and investigating EEG feature-spaces to increase detection robustness
Errare machinale est: The use of error-related potentials in brain-machine interfaces
The ability to recognize errors is crucial for efficient behavior. Numerous studies have identified electrophysiological correlates of error recognition in the human brain (error-related potentials, ErrPs). Consequently, it has been proposed to use these signals to improve human-computer interaction (HCI) or brain-machine interfacing (BMI). Here, we present a review of over a decade of developments towards this goal. This body of work provides consistent evidence that ErrPs can be successfully detected on a single-trial basis, and that they can be effectively used in both HCI and BMI applications. We first describe the ErrP phenomenon and follow up with an analysis of different strategies to increase the robustness of a system by incorporating single-trial ErrP recognition, either by correcting the machine's actions or by providing means for its error-based adaptation. These approaches can be applied both when the user employs traditional HCI input devices or in combination with another BMI channel. Finally, we discuss the current challenges that have to be overcome in order to fully integrate ErrPs into practical applications. This includes, in particular, the characterization of such signals during real(istic) applications, as well as the possibility of extracting richer information from them, going beyond the time-locked decoding that dominates current approaches
PROBLEMS WITH DETERMINATION OF FUGITIVE EMISSION OF POLYCYCLIC AROMATIC HYDROCARBONS FROM COKE OVEN BATTERY
Coke oven battery is complex and multifaceted facility in terms of air pollutant emissions. As far as stack or quenching tower does not cause major difficulties of emission measurement, the fugitive emission measurement from sources such as battery top elements (charging holes, ascension pipes) or oven doors is still complicated and not fully solved problem. This article presents the discussion concerning main problems and errors likely to be made in particular stages of procedure of fugitive emissions characterization from coke oven battery (selection of sampling points, sampling itself, measurement of air velocity over battery top and laboratory analyses). In addition, results of concentrations measurements of selected substances characteristic for the coking process (naphthalene, anthracene, 4 PAHs and TSP) originating from fugitive sources of coke oven battery and subjected to reporting under the E-PRTR are presented. The measurements were carried out on coke oven battery top in points selected on the basis of the preceding detailed air convection velocity measurements over battery top. Results of the velocity measurements were compared with results of numerical modelling using CFD software. The presented material is an attempt to cross-sectional presentation of issues related to the quantitative evaluation of fugitive emission from coke oven battery, discussed on the example of PAHs emission as a group of substances characteristic for coking of coal
Modulation of the inter-hemispheric asymmetry of motor-related brain activity using brain-computer interfaces
Non-invasive brain stimulation has shown promis- ing results in neurorehabilitation for motor-impaired stroke patients, by rebalancing the relative involvement of each hemisphere in movement generation. Similarly, brain-computer interfaces have been used to successfully facilitate movement- related brain activity spared by the infarct. We propose to merge both approaches by using BCI to train stroke patients to rebalance their motor-related brain activity during motor tasks, through the use of online feedback. In this pilot study, we report results showing that some healthy subjects were able to learn to spontaneously up- and/or down-regulate their ipsilateral brain activity during a single session
External quality monitoring facilitates improvement in already well-performing stroke units: insights from RES-Q Poland
Introduction. The Registry of Stroke Care Quality (RES-Q) is used in Poland for quality monitoring by numerous hospitals participating in the Angels Initiative. Our aim was to assess the degree of improvement in highly stroke-oriented centres that report cases to the RES-Q each year.
Material and methods. This retrospective analysis included Polish stroke units that from January 2017 to December 2020 contributed to the RES-Q at least 25 patients annually.
Results. Seventeen out of 180 Polish stroke units reported patients each year (2017, n = 1,691; 2018, n = 2,986; 2019, n = 3,750; 2020, n = 3,975). The percentage of ischaemic stroke patients treated with alteplase remained stable (26%, 29%, 30% and 28%, respectively). The door-to-needle time progressively decreased, from a median 49 minutes to 32 minutes. The percentage of patients treated ≤ 60 minutes and ≤ 45 minutes significantly increased (from 68% to 86% and from 43% to 70%, respectively), with no change observed between 2019 and 2020. Despite a general improvement in dysphagia screening (81%, 91%, 98% and 99%), screening performed within the first 24h from admission became less frequent (78%, 76%, 69% and 65%). In-hospital mortality significantly increased (11%, 11%, 13% and 15%), while the proportion of patients discharged home remained stable.
Conclusions. Quality-oriented projects facilitate the improvement of stroke care, even in centres demonstrating good baseline performance. Polish stroke units that consistently reported cases to the RES-Q demonstrated improvement in terms of door-to- -needle time and dysphagia screening. However, there is still a need to shorten the time to dysphagia screening, and carefully monitor stroke unit mortality following the COVID-19 pandemic
Slovak brown coals as a feedstock for the active coke production
V èlánku sa venuje pozornos monostiam výroby aktívneho koksu zo slovenského hnedého uhlia Bane Cíge¾. Príprava aktívneho koksu bola uskutoènená v laboratórnych podmienkach a v poloprevádzke. Surové uhlie sa podrobilo vysokoteplotnej pyrolýze v retorte s pevným rotom, v klasickej rotaènej peci, ako aj vo fluidnom reaktore. Následne boli urèované adsorpèné charakteristiky získaného aktívneho koksu, ktoré sa porovnávali s charakteristikami komerène vyrábaného koksu. V príspevku sa taktie diskutujú monosti aplikácie pripraveného aktívneho koksu v technológiách ochrany ivotného prostredia