Refocusing sustainability education: using students’ reflections on their carbon footprint to reinforce the importance of considering CO2 production in the construction industry

The construction industry is the most significant contributor to the UK’s CO2 emissions. It is responsible for an annual output of approximately 45% of the total. This figure highlights the role the industry must play in helping to achieve the UK Government’s CO2 reduction target. It is ergo incumbent on construction-related educators to emphasise this issue and explore ways in which it can be achieved. Unintentional desensitisation has resulted in the term ‘sustainability’, particularly CO2 production, being seen by students as just another concept to be studied from a theoretical perspective. Many students fail to grasp its broader implications and how it should affect strategic environmental decisions about construction processes, technologies, and products. In an attempt to address this problem, an innovative learning, teaching, and assessment strategy was used with final year undergraduate construction students to improve their level of sustainability literacy. The theory of threshold concepts in the context of transformative learning was used as the baseline philosophy to the study. The approach involved asking students to calculate their carbon footprint and to reflect upon and extrapolate their findings to the construction industry and its practice. Content analysis was performed on the reflective commentaries acquired from student portfolios collected over four academic years. The results showed how the students’ reflections on their carbon footprints proved to be an enlightening experience. Terms such as ‘shocked by my footprint’, ‘surprised at the findings’, and ‘change in attitude’ were among the contemplative comments. When students linked their findings to the construction industry, phrases such as ‘waste generation’, ‘technologies’, and ‘materials’ were some of the concepts considered. By using their personal experiences as a benchmark, students were able to gain a deeper level of understanding of the causes and consequences of CO2 production. They also found it more straightforward to relate these issues to the construction industry and its practice. Several novel recommendations are made to raise the level of sustainability literacy in the construction industry thereby facilitating a potential reduction in worldwide CO2 production

Vortex generation in protoplanetary disks with an embedded giant planet

Vortices in protoplanetary disks can capture solid particles and form planetary cores within shorter timescales than those involved in the standard core-accretion model. We investigate vortex generation in thin unmagnetized protoplanetary disks with an embedded giant planet with planet to star mass ratio $10^{-4}$ and $10^{-3}$. Two-dimensional hydrodynamical simulations of a protoplanetary disk with a planet are performed using two different numerical methods. The results of the non-linear simulations are compared with a time-resolved modal analysis of the azimuthally averaged surface density profiles using linear perturbation theory. Finite-difference methods implemented in polar coordinates generate vortices moving along the gap created by Neptune-mass to Jupiter-mass planets. The modal analysis shows that unstable modes are generated with growth rate of order $0.3 \Omega_K$ for azimuthal numbers m=4,5,6, where $\Omega_K$ is the local Keplerian frequency. Shock-capturing Cartesian-grid codes do not generate very much vorticity around a giant planet in a standard protoplanetary disk. Modal calculations confirm that the obtained radial profiles of density are less susceptible to the growth of linear modes on timescales of several hundreds of orbital periods. Navier-Stokes viscosity of the order $\nu=10^{-5}$ (in units of $a^2 \Omega_p$) is found to have a stabilizing effect and prevents the formation of vortices. This result holds at high resolution runs and using different types of boundary conditions. Giant protoplanets of Neptune-mass to Jupiter-mass can excite the Rossby wave instability and generate vortices in thin disks. The presence of vortices in protoplanetary disks has implications for planet formation, orbital migration, and angular momentum transport in disks.Comment: 14 pages, 15 figures, accepted for publication in A&

On Validating an Astrophysical Simulation Code

We present a case study of validating an astrophysical simulation code. Our study focuses on validating FLASH, a parallel, adaptive-mesh hydrodynamics code for studying the compressible, reactive flows found in many astrophysical environments. We describe the astrophysics problems of interest and the challenges associated with simulating these problems. We describe methodology and discuss solutions to difficulties encountered in verification and validation. We describe verification tests regularly administered to the code, present the results of new verification tests, and outline a method for testing general equations of state. We present the results of two validation tests in which we compared simulations to experimental data. The first is of a laser-driven shock propagating through a multi-layer target, a configuration subject to both Rayleigh-Taylor and Richtmyer-Meshkov instabilities. The second test is a classic Rayleigh-Taylor instability, where a heavy fluid is supported against the force of gravity by a light fluid. Our simulations of the multi-layer target experiments showed good agreement with the experimental results, but our simulations of the Rayleigh-Taylor instability did not agree well with the experimental results. We discuss our findings and present results of additional simulations undertaken to further investigate the Rayleigh-Taylor instability.Comment: 76 pages, 26 figures (3 color), Accepted for publication in the ApJ

Equilibrium configurations of two charged masses in General Relativity

An asymptotically flat static solution of Einstein-Maxwell equations which describes the field of two non-extreme Reissner - Nordstr\"om sources in equilibrium is presented. It is expressed in terms of physical parameters of the sources (their masses, charges and separating distance). Very simple analytical forms were found for the solution as well as for the equilibrium condition which guarantees the absence of any struts on the symmetry axis. This condition shows that the equilibrium is not possible for two black holes or for two naked singularities. However, in the case when one of the sources is a black hole and another one is a naked singularity, the equilibrium is possible at some distance separating the sources. It is interesting that for appropriately chosen parameters even a Schwarzschild black hole together with a naked singularity can be "suspended" freely in the superposition of their fields.Comment: 4 pages; accepted for publication in Phys. Rev.

Prism users guide.

Prism is a ParaView plugin that simultaneously displays simulation data and material model data. This document describes its capabilities and how to use them. A demonstration of Prism is given in the first section. The second section contains more detailed notes on less obvious behavior. The third and fourth sections are specifically for Alegra and CTH users. They tell how to generate the simulation data and SESAME files and how to handle aspects of Prism use particular to each of these codes

From student to young professional: Exploring the impact of work-based placements on the transformation of undergraduate construction students

From education to accountancy, nursing to tourism, literature is awash with studies relating to work-based placements yet there appears to be little which specifically addresses the construction industry. Work-based placement literature often argues that students return to university from their placement a different person, somehow transformed. However, the majority of this literature focusses on the transformative outcome, with little empirical research investigating the transformational process itself. The following thesis offers a phenomenological study which seeks to address these two gaps in knowledge by exploring the transformational journey upon which construction undergraduates travel during a work-based placement. Framed within Jack Mezirow’s transformative learning theory, it investigates work-based placements from the student’s perspective, examining the issues they face and searching for answers to how and if a placement can affect the transformation of students. A mixed methods approach consisting of semi-structured interviews and a self-administered explorative questionnaire was used to examine the experiences of placement students before and after their placement. The qualitative data were subjected to a thematic analysis to establish key themes, while the quantitative data were subjected to a series of statistical tests and summaries to uncover patterns, associations and differences. The data revealed that at the beginning of their placement students had an overwhelming sense of inadequacy, a lack of confidence and an uncertainty as to how they would perform and, while learning was clearly taking place, at times it was almost on an ad-hoc basis. Transformation was occurring but many students were unaware of this change. There were many factors which contributed to their transformation with the key finding being a self-perpetuating cycle of an increase in knowledge and experience leading to increased confidence which gradually changed them from student to young professional

Nuclear Energy -- Knowledge Base for Advanced Modeling and Simulation (NE-KAMS) Code Verification and Validation Data Standards and Requirements: Fluid Dynamics Version 1.0

V&V and UQ are the primary means to assess the accuracy and reliability of M&S and, hence, to establish confidence in M&S. Though other industries are establishing standards and requirements for the performance of V&V and UQ, at present, the nuclear industry has not established such standards or requirements. However, the nuclear industry is beginning to recognize that such standards are needed and that the resources needed to support V&V and UQ will be very significant. In fact, no single organization has sufficient resources or expertise required to organize, conduct and maintain a comprehensive V&V and UQ program. What is needed is a systematic and standardized approach to establish and provide V&V and UQ resources at a national or even international level, with a consortium of partners from government, academia and industry. Specifically, what is needed is a structured and cost-effective knowledge base that collects, evaluates and stores verification and validation data, and shows how it can be used to perform V&V and UQ, leveraging collaboration and sharing of resources to support existing engineering and licensing procedures as well as science-based V&V and UQ processes. The Nuclear Energy Knowledge base for Advanced Modeling and Simulation (NE-KAMS) is being developed at the Idaho National Laboratory in conjunction with Bettis Laboratory, Sandia National Laboratories, Argonne National Laboratory, Utah State University and others with the objective of establishing a comprehensive and web-accessible knowledge base to provide V&V and UQ resources for M&S for nuclear reactor design, analysis and licensing. The knowledge base will serve as an important resource for technical exchange and collaboration that will enable credible and reliable computational models and simulations for application to nuclear power. NE-KAMS will serve as a valuable resource for the nuclear industry, academia, the national laboratories, the U.S. Nuclear Regulatory Commission (NRC) and the public and will help ensure the safe, economical and reliable operation of existing and future nuclear reactors