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This paper summarized the efforts performed to understand decay heat estimation from existing spent nuclear fuel (SNF), under the auspices of the Working Party on Nuclear Criticality Safety (WPNCS) of the OECD Nuclear Energy Agency. Needs for precise estimations are related to safety, cost, and optimization of SNF handling, storage, and repository. The physical origins of decay heat (a more correct denomination would be decay power) are then introduced, to identify its main contributors (fission products and actinides) and time-dependent evolution. Due to limited absolute prediction capabilities, experimental information is crucial; measurement facilities and methods are then presented, highlighting both their relevance and our need for maintaining the unique current full-scale facility and developing new ones. The third part of this report is dedicated to the computational aspect of the decay heat estimation: calculation methods, codes, and validation. Different approaches and implementations currently exist for these three aspects, directly impacting our capabilities to predict decay heat and to inform decision-makers. Finally, recommendations from the expert community are proposed, potentially guiding future experimental and computational developments. One of the most important outcomes of this work is the consensus among participants on the need to reduce biases and uncertainties for the estimated SNF decay heat. If it is agreed that uncertainties (being one standard deviation) are on average small (less than a few percent), they still substantially impact various applications when one needs to consider up to three standard deviations, thus covering more than 95% of cases. The second main finding is the need of new decay heat measurements and validation for cases corresponding to more modern fuel characteristics: higher initial enrichment, higher average burnup, as well as shorter and longer cooling time. Similar needs exist for fuel types without public experimental data, such as MOX, VVER, or CANDU fuels. A third outcome is related to SNF assemblies for which no direct validation can be performed, representing the vast majority of cases (due to the large number of SNF assemblies currently stored, or too short or too long cooling periods of interest). A few solutions are possible, depending on the application. For the final repository, systematic measurements of quantities related to decay heat can be performed, such as neutron or gamma emission. This would provide indications of the SNF decay heat at the time of encapsulation. For other applications (short- or long-term cooling), the community would benefit from applying consistent and accepted recommendations on calculation methods, for both decay heat and uncertainties. This would improve the understanding of the results and make comparisons easier.

This study examines the program- and individual-level factors that impact the success of drug court clients in terms of: (1) graduation; and (2) not being arrested while participating in the court program. The data consist of 848 individuals in nine drug courts. This paper discusses how different individual- and program-level factors impact the success of drug court participants. The findings suggest that individual- and program-level factors are both important in predicting program graduation and arrest during drug court participation, while controlling for participant demographics. Clients' education, drug/alcohol usage, program staffing, and clinical standards impact program graduation while criminal history, drug/alcohol usage, number of program hours offered, program staffing, and use of rewards and sanctions predict in-program arrest. Models combining both program- and individual-level factors performed better than either alone, leading to recommendations that agencies should emphasize improving program quality while targeting clients' needs to achieve greater success. [ABSTRACT FROM AUTHOR]

The kindred approaches of medieval philosopher St. Anselm and Hegel are taken into account for exploring the relationship between religious and philosophical thought. It is argued that both support logic of unity but Anselm states that the mystery of God's existence is not entirely outside the boundaries of understanding whereas Hegel argues that traditional ideas about God's existence are rendered unsustainable by unifying human and divine spheres.

Wisdom and Action Guidance in the Agent-Based Virtue Ethics of Aristotle, THOMAS SHERMAN, S.J. While Aristotle in the Nicomachean Ethics does not provide a guide for action in the form [...]

Non-pharmaceutical interventions (NPIs) remain the only widely available tool for controlling the ongoing SARS-CoV-2 pandemic. We estimated weekly values of the effective basic reproductive number (Reff) using a mechanistic metapopulation model and associated these with county-level characteristics and NPIs in the United States (US). Interventions that included school and leisure activities closure and nursing home visiting bans were all associated with a median Reff below 1 when combined with either stay at home orders (median Reff 0.97, 95% confidence interval (CI) 0.58–1.39) or face masks (median Reff 0.97, 95% CI 0.58–1.39). While direct causal effects of interventions remain unclear, our results suggest that relaxation of some NPIs will need to be counterbalanced by continuation and/or implementation of others. Disentangling the impacts of non-pharmaceutical interventions on COVID-19 transmission is challenging as they have been used in different combinations across time and space. This study shows that, early in the epidemic, school/daycare closures and stopping nursing home visits were associated with the biggest reduction in transmission in the United States. [ABSTRACT FROM AUTHOR]

The response of a thermosetting cross-linked polyethylene, commercially referred to as Vitrite, has been studied experimentally and numerically. Two different testing programmes have been carried out; the first to characterise the mechanical properties of the material, and the second to provide information to validate a finite element model. Strain-rate dependent stress–strain curves have been obtained to determine the static and dynamic mechanical properties of Vitrite in tension and compression. Guided drop testing of a mass onto small scale samples has been used to study their deformation and rebound response. This has been compared to the deformation results of a finite element analysis model of the drop tests using the data obtained from the material characterisation tests as input to the model. [ABSTRACT FROM AUTHOR]

Freight rail is often the preferred method for transportation of dangerous goods. One particular application is the use of rail to convey radioactive material in purpose-built packages. During transit, packages are secured to a rail wagon bed with a tie-down system. The design of tie-down systems varies considerably depending on the package type and rail vehicle; for example, shackles, turnbuckles, tie rods, gravity wells or transport frames are all commonly used. There are also a large number of different packages in existence that all vary in size and mass, typically 1-7m in length and 100 kg- 100 t in mass. Despite the uniqueness of many transport configurations, the design of tie-down systems is always carried out using a limited set of design load cases as defined in the appropriate Codes of Practice and Standards. Many authors have suggested that the load cases within the standards need revision or question which load cases should apply to which scenario. In a previous experiment, accelerations and strains have been measured on a freight wagon and transport frame of a heavy package during a routine rail journey. From these data, a new insight into the magnitude and nature of loading has been gained. In the present study, the measured accelerations have been used as input to a finite element model of the transport frame, and a method based on correlation between predicted and measured strains has been developed to determine an appropriate low-pass filter cut-off frequency, fc, which separates quasi-static loading from raw dynamic data. The residual dynamic measurements have been assessed using signal processing techniques to understand their significance. The finite element model has also been used to assess the presence of contact and boundary nonlinearities and how they affect the agreement between measured and predicted strains. [ABSTRACT FROM AUTHOR]

In 2004 a much-publicized discussion took place between the political philosopher Jürgen Habermas and the Catholic theologian Joseph Ratzinger (the future Pope Benedict XVI). Essentially, the role of religion in the public sphere was at stake. Habermas, speaking of a "post-secular" age, attempted to find a more vocal place for religious views, subject to a "translation proviso." Ratzinger, while acknowledging the need for better dialogue between the religious and the secular, argued that there was no longer a common basis for it in "natural reason." Both figures can be seen as speaking to the practical and the theoretical aspects of the dialogue, respectively. Once this difference is understood, Habermas's suggestions can be accepted. [ABSTRACT FROM AUTHOR]

Communication is a complex two-way process, involving the encoding, translation, and decoding of both verbal and non-verbal cues. The most fundamental cue we utilize when communicating with others is that of the human face (Ekman, 1993). Facial expressions may signal our own internal conscious experiences or they may serve to influence the actions and cognitions of others. To examine how children interpret, perceive, encode, and respond tofacial cues in their social environments, the chapter will review their facial expression recognition within the framework of the social information processing (SIP) model (Crick and Dodge, 1994). The SIP model is useful because it assumes that the way in which children understand and interpret cues within social situations directly influences their behaviors and decision-making choices (Lemerise and Arsenio, 2000). The proposed chapter will examine the specific cues children rely upon while engaged in a social encounter. For example, children's own personal characteristics (e.g., age and sex) impact their emotion recognition aptitude (Mayeux and Cillessen, 2003). Children also utilize various attributes from a target's face (e.g., emotional expression, gender, and personal familiarity) while engaged in emotion recognition, thereby impacting the development of their social goals and problem-solving choices (Lemerise, Gregory, and Fredstrom, 2005). Additionally, the context or difficulty of the social task they are required to complete influences their ability to correctly identify the expressions of others (Cummings and Rennels, 2014). This chapter provides an overview of how perceiver effects, target characteristics, and context influence children's encoding and interpretation of emotion, and considers these findings within the social information processing framework. [ABSTRACT FROM AUTHOR]