Carbon capture in the cement industry: technologies, progress, and retrofitting

Several different carbon-capture technologies have been proposed for use in the cement industry. This paper reviews their attributes, the progress that has been made toward their commercialization, and the major challenges facing their retrofitting to existing cement plants. A technology readiness level (TRL) scale for carbon capture in the cement industry is developed. For application at cement plants, partial oxy-fuel combustion, amine scrubbing, and calcium looping are the most developed (TRL 6 being the pilot system demonstrated in relevant environment), followed by direct capture (TRL 4–5 being the component and system validation at lab-scale in a relevant environment) and full oxy-fuel combustion (TRL 4 being the component and system validation at lab-scale in a lab environment). Our review suggests that advancing to TRL 7 (demonstration in plant environment) seems to be a challenge for the industry, representing a major step up from TRL 6. The important attributes that a cement plant must have to be “carbon-capture ready” for each capture technology selection is evaluated. Common requirements are space around the preheater and precalciner section, access to CO2 transport infrastructure, and a retrofittable preheater tower. Evidence from the electricity generation sector suggests that carbon capture readiness is not always cost-effective. The similar durations of cement-plant renovation and capture-plant construction suggests that synchronizing these two actions may save considerable time and money

On some classes of lazy cocycles and categorical structures

We study some classes of lazy cocycles, called pure (respectively neat), together with their categorical counterparts, entwined (respectively strongly entwined) monoidal categories.Comment: Final version; 18 pages; the title has been changed; the order of the sections has been changed; some things have been removed and appear now in arXiv:0801.205

The prevalence of high dysplastic colonic adenomatous polyps in a 3 year endoscopic retrospective study from a single clinical center

Introduction: Many colon neoplastic tumors come from the malignancy of adenomatous polyps (70%-90%) that were not timely diagnosed in order to be resected. Materials and Methods: We conducted a retrospective study regarding the incidence of adenomatous polyps during 1.000 consecutive colonoscopies performed in our Upper and Lower Digestive Endoscopy Laboratory during a three-year period. Results: During these colonoscopies, some targeted polyps were biopsied or completely removed and the samples had been sent to a complete anatomopathological examination. Taking into consideration the results, the polyps were classified after the histological type and the form of dysplasia, in order to determine the polyp forms that present a high risk of malignancy. Conclusion: Given the rather high frequency of malignant polyps discovered during our study, we highly recommend colonoscopy as a method of choice for routine monitoring of selected cases

STRATEGY MANAGEMENT IN A MULTI-AGENT SYSTEM USING NEURAL NETWORKS FOR INDUCTIVE AND EXPERIENCE-BASED LEARNING

Intelligent agents and multi-agent systems prove to be a promising paradigm for solving problems in a distributed, cooperative way. Neural networks are a classical solution for ensuring the learning ability of agents. In this paper, we analyse a multi-agent system where agents use different training algorithms and different topologies for their neural networks, which they use to solve classification and regression problems provided by a user. Out of the three training algorithms under investigation, Backpropagation, Quickprop and Rprop, the first demonstrates inferior performance to the other two when considered in isolation. However, by optimizing the strategy of accepting or rejecting tasks, Backpropagation agents succeed in outperforming the other types of agents in terms of the total utility gained. This strategy is learned also with a neural network, by processing the results of past experiences. Therefore, we show a way in which agents can use neural network models for both external purposes and internal ones.agents, learning, neural networks, strategy management multi-agent system.

Kindergarten Teachers\u27 Classroom Management Beliefs and Practices and Their Implications on Students\u27 Social and Academic Outcomes

The purpose of this study was to utilize Baumrind\u27s parenting style construct, with early childhood educators, as classroom management styles by assessing the proportion of classroom management styles of Virginia Association of Early Childhood Education (VAECE) educators, and secondly to assess classroom management beliefs and practices of among urban kindergarten teachers in addition to examining whether those differing classroom management styles impacted students\u27 social and academic skills. The study investigated the proportion of classroom management styles of VAECE educators using an online questionnaire and used a case study approach with nine kindergarten teachers to better understand the teachers\u27 classroom management beliefs and practices with interviews, self-report questionnaires, and observations. Students\u27 academic skills were measured using standardized literacy assessment scores and social skills using teacher reports. Results revealed that all educators reported themselves to be authoritative using the online questionnaire. Furthermore, the case study teachers also all reported themselves to be authoritative in the interview and the questionnaire; however, observations revealed seven teachers to be authoritative, one to be authoritarian, and one to be negative directive, a newly created style. Overall, the teachers understood their classroom management strategies and where they originated from, and believed their styles to positively impact both their students\u27 social and academic skills, regardless of the style they utilized. The classroom management styles did not show any statistical significance regarding student outcomes; however, ranking the teachers based on their students\u27 academic and social skills did reveal authoritative teachers to have students\u27 with higher social skills but not academic skills. This study helped create a bridge in the literature for the use of Baumrind\u27s parenting styles to be used with early childhood teachers as classroom management styles. Since Baumrind\u27s parenting styles have been studied for over forty years and are a foundation in the parenting literature, being able to understand them from a teaching standpoint may help answer critical questions regarding the impact of teachers on students