An experimental study has been performed on the dynamics of a large turbulent buoyanthelium plume. Two-dimensional velocity fields were measured using particle image velocimetry (PIV) while helium mass fraction was determined by planar laser-induced fluorescence (PLIF). PIV and PLIF were performed simultaneously in order to obtain velocity and mass fraction data over a plane that encompassed the plume core, the near-field mixing zones and the surrounding air. The Rayleigh–Taylor instability at the base of the plume leads to the vortex that grows to dominate the flow. This process repeats in a cyclical manner. The temporally and spatially resolved data show a strong negative correlation between density and vertical velocity, as well as a strong 90° phase lag between peaks in the vertical and horizontal velocities throughout the flow field owing to large coherent structures associated with puffing of the turbulent plume. The joint velocity an mass fraction data are used to calculate Favre-averaged statistics in addition to Reynolds-(time) averaged statistics. Unexpectedly, the difference between both the Favre-averaged and Reynolds-averaged velocities and second-order turbulent statistics is less than the uncertainty in the data throughout the flow field. A simple analysis was performed to determine the expected differences between Favre and Reynolds statistics for flows with periodic fluctuations in which the density and velocity fields are perfectly correlated, but have the phase relations as suggested by the data. The analytical results agreewith the data, showing that the Favre and Reynolds statistics will be the same to lead order. The combination of observation and simple analysis suggests that for buoyancy-dominated flows in which it can be expected that density and velocity are strongly correlated,phase relations will result in only second-order differences between Favre- and Reynolds-averaged data in spite of strong fluctuations in both density and velocity.

A variety of pedagogies have become well-established and widely used in engineering education including problem-based learning (PBL), project-based learning, case-based learning, and inquiry-based learning. All of these classroom techniques certainly emphasize skill-based learning outcomes (e.g., determine the size of a pump), but they do not always emphasize mindset-based learning outcomes (e.g., identify an unexpected opportunity). Incorporating elements of the entrepreneurial mindset into these pedagogies, sometimes referred to as entrepreneurially minded learning (EML), can enhance student learning and produce a more realworld experience. Entrepreneurially minded learning emphasizes discovery, opportunity identification, and value creation with attention given to effectual thinking over causal (predictive) thinking.After introducing the concept of EML, this paper focuses on EML within the context of PBL.For a framework to demonstrate how to incorporate stakeholders, discovery, opportunity identification, and value creation, specific examples from Fluid Mechanics courses will be presented. In particular, the PBL course modules will demonstrate assignments that include unexpected design alternatives that the students must discover with scant clues (much like "Easter eggs" hidden in movies or DVDs). When discovered the design alternatives prove to have added value over a traditional design (i.e., value creation). One of the keys to producing these assignments is to incorporate a stakeholder or customer. Because stakeholder feedback is essential to re-evaluate opportunities and/or understanding what is deemed as valuable (i.e., value is subjective), it is important for the assignments to include a real live customer (who can be a fictional role-player). In addition, the examples given in this paper follow a similar theme (or consistent customer) with a bit of added humor. Doing so has shown to create enthusiasm for the assignment and the subject material.To determine preliminary effectiveness of EML within PBL, both indirect and direct assessment have been performed. For direct assessment, students' EML assignments were evaluated by the instructor to verify inclusion or exclusion of a set of entrepreneurially minded attributes. For indirect assessment, students were surveyed to determine their perceived extent of using particular entrepreneurial mindset skills during an EML assignment. The results have thus far yielded positive results for students incorporating mindset skills into subject-based matter.

No abstract

This article narrates part of the history of salmon flu in the Chilean salmon industry, and attempts to tie together environmental history and political ecology in order to reveal the complicated non-human and human collectives that constitute its "ecological rubble." It draws from ethnographic and archival research to show the views among salmon farm workers and local Chilotes who both supported and contested the industry in contradictory ways. Amidst a milieu of technocratic narratives of control, and blindness to nonhuman agencies, they themselves became simultaneously part of new forms of ecological rubble: hidden harms the industry brought to their archipelagic home. I argue that only through an awareness of these hidden collectives of both material and human social relations can we hope to weather the storms of production and destruction that industrial aquaculture births at sea. Key words: environmental history, aquaculture, disease, agriculture, salmon farming, Latin America, Chile. RésuméCet article raconte un morceau de l'histoire de la grippe du saumon dans l'industrie chilienne du saumon et tente de relier l'histoire de l'environnement et de l'écologie politique dans le but de révéler les collectifs non humains et humains complexes qui constituent ses décombres écologique. Il puise dans la recherche ethnographique et d'archives pour montrer les vues entre les travailleurs agricoles de saumon et Chilotes locales qui ont tous deux pris en charge et contesté l'industrie de façon contradictoire. Au milieu d'un milieu de récits technocratiques de contrôle, et la cécité aux organismes non-humains, ils devinrent eux-mêmes en même temps une partie de nouvelles formes de décombres écologique: les méfaits cachés de l'industrie a apporté à leur domicile archipélagique. Je soutiens que seulement à travers une prise de conscience de ces collectifs cachés de la fois matériel et des relations sociales de l'homme que nous pouvons espérer affronter les tempêtes de la production et la destruction que les naissances d'aquaculture industrielles en mer. Mots clés: histoire de l'environnement, de l'aquaculture, la maladie, l'agriculture, l'élevage du saumon, l'Amérique latine, le Chili. ResumenEste artículo explica un pedazo de la historia de la gripe salmón en la industria del salmón en Chile y los intentos de unir la historia del medio ambiente y la ecología política con el fin de revelar los colectivos complicados no humanos y humanos que constituyen sus escombros ecológica. Se basa en la investigación etnográfica y de archivo para mostrar los puntos de vista entre los trabajadores de salmón y los chilotes locales que apoyaron y disputado la industria de forma contradictoria. En medio de un entorno de narrativas tecnocráticos de control, y la ceguera de los organismos no humanos, ellos mismos se convierten simultáneamente en parte de nuevas formas de escombros ecológica: daños ocultos de la industria trajo a su casa archipelágica. Argumento que sólo a través de una toma de conciencia de estos colectivos ocultos...

No abstract

A previous teaching grant from the National Fluid Power Association provided senior mechanical engineering students a project to design and fabricate a fluid-powered gantry crane. During fabrication, assembly, and testing of the fluid-powered gantry crane, a number of areas for improvement of the student design were identified. Among these were the inclusion of a control system to limit load swing, redesign of the fluid distribution system, redesign to reduce binding between the trolley and crossbar, and heat sink design for cooling of the electrical system. Rather than fixing the deficiencies with a second senior design project, problem-based learning (PBL) exercises were developed to introduce more students to fluid power using the existing gantry crane. The PBL modules were implemented in junior and senior Mechanical Engineering courses including Mechatronics, Fluid Mechanics, and Heat Transfer. After the PBL activities, direct assessment with a common rubric was used to evaluate the quality of problem solutions and student surveys were used to qualitatively assess the effectiveness of the PBL experience. The assessment results indicate that the PBL activities contributed to student learning both on concepts introduced in class and on problem solving skills which required synthesis of material from class.

He received his B.S. in mechanical engineering from Khulna University of Engineering and Technology, Bangladesh; M.S. in systems and engineering management from Nanyang Technological University, Singapore, and Ph.D. in industrial engineering from University of Wisconsin, Milwaukee. He has published journal and conference papers. His research interests include manufacturing systems modelling, simulation and optimisation, reliability, scheduling, artificial intelligence, e-manufacturing, and lean manufacturing. He is member of IIE, INFORMS, SME, and IEEE.

No abstract