A Discrete Four Stroke Quantum Heat Engine Exploring the Origin of Friction

The optimal power performance of a first principle quantum heat engine model shows friction-like phenomena when the internal fluid Hamiltonian does not commute with the external control field. The model is based on interacting two-level-systems where the external magnetic field serves as a control variable.Comment: 4 pages 3 figure

Strong Firms Lobby, Weak Firms Bribe: A survey-based analysis of the demand for influence and corruption

We use survey responses by firms to examine the firm-level determinants and effects of political influence, their perception of corruption and prevalence of bribe paying. We find that: (a) measures of political influence and corruption/bribes are uncorrelated at the firm level; (b) firms that are larger, older, exporting, government-owned, are widely held and/or have fewer competitors, have more political influence, perceive corruption to be less of a problem and pay bribes less often; (c) influence increases sales and government subsidies and in general makes the firm have a more positive view on the government. In sum, we show that strong firms use their influence to bend laws and regulations, whereas weak firms pay bribes to mitigate the costs of government intervention.

An Exploratory Study of the Trends Emerging from a Forced Shift to a Digital Interface on University Faculty\u27s Instructional Design

The COVID-19 crisis upended the typical college experience as educational institutions had to close campuses and send students home mid-semester in the spring of 2020. The COVID-19 pandemic left educators around the world with limited choices on how to move forward with high quality education for all. This abrupt closing of higher education facilities forced an immediate pivot to online synchronous or asynchronous digital classrooms for faculty and students and ushered in emergency remote teaching. While higher education has gradually expanded online offerings every year over the past twenty years, for many college students, classes were still in person until the pandemic swept across the world in March 2020. This exploratory research study investigates trends emerging during a forced shift to a digital interface on university faculty\u27s instructional design regarding course content, assessment, and student engagement during the COVID-19 pandemic. A mixed data approach was used including an online self-assessment survey and in-depth online course shell reviews. This information was utilized to answer three questions for this study: What differences or patterns are taking place in content delivery? What differences or patterns are taking place in assessment? What differences or patterns are taking place with student engagement? The survey was administered to 46 faculty members who taught during the 2021 spring and/or summer semesters during the worldwide COVID-19 pandemic and 27 of these 46 faculty members agreed to an in-depth course shell review during the same timeframe. Results from the survey indicated faculty had a high sense of self-efficacy with technology and felt confident finding technology tools, learning to use them, and implementing them during instruction. The data analysis indicated emerging practices around the following themes in content delivery, assessment, and student engagement: (a) consistent use of a set of technology tools, (b) video lectures, (c) active learning, (d) online assessments, (e) written feedback, (f) rubrics, (g) multiple means of communicating with the instructor, (h) students providing rich feedback to peers, and (i) synchronous opportunities for students to connect with peers. This research adds to the field of knowledge on emergency online teaching, online learning, and high-quality online courses by sharing the trends that emerged from teaching during this historic moment in time

Self Piercing Riveting for Metal-Polymer Joints

Self-Piercing Riveting (SPR) is a sheet metal joining technique based on the insertion of a rivet into two or more sheets, with no preparatory hole. This process has gained wide diffusion in the automotive industry, due to the increasing use of materials alternative to steel, that are difficult or impossible to join with traditional techniques. In particular, polymeric materials are becoming increasingly used, due to their favorable weight/strength ratio. This paper reports the results of experimental investigations, aimed at identifying the variables affecting the mechanical characteristics of mixed metal-plastic joints. A statistic model for the optimization of the geometrical parameters has been computed. The paper demonstrates that self-piercing riveting appears competitive for metal/polymer junction. The results analyzed in light of statistical techniques show that some geometrical parameters affect joint performance more than others and can therefore be used as independent variables for joint performance optimizatio

Changes in vegetation spectra with deterioration of leaves under two methods of preservation

An experiment to measure changes in leaf spectra under different methods of preservation over time was conducted. The spectral measurements were made by a three band hand held radiometer which simulated three Thematic Mapper (TM) bands: TM3, TM4, and TM5. Daily spectral measurements of white oak leaves under three preservation treatments were made. The spectral readings over three treatments (fresh, bottled, and bagged vegetation) were indistinguishable in bands TM3 and TM5 for up to 4 days after collection. After that time bagged and bottled samples showed significant increases in reflected energy caused by loss of chlorophyll from and dehydration of the vegetation. No significant variation in the reflectance values from TM4 over preservation type for the experimental period was observed

Pseudoscalar Meson Mixing in Effective Field Theory

We show that for any effective field theory of colorless meson fields, the mixing schemes of particle states and decay constants are not only related but also determined exclusively by the kinetic and mass Lagrangian densities. In the general case, these are bilinear in terms of the intrinsic fields and involve non-diagonal kinetic and mass matrices. By applying three consecutive steps this Lagrangian can be reduced into the standard quadratic form in terms of the physical fields. These steps are : (i) the diagonalization of the kinetic matrix, (ii) rescaling of the fields, and (iii) the diagonalization of the mass matrix. In case, where the dimensions of the non-diagonal kinetic and mass sub-matrices are respectively, $k\times k$ and $n\times n$, this procedure leads to mixing schemes which involve $[k(k-1)/2] + [n(n-1)/2]$ angles and $k$ field rescaling parameters. This observation holds true irrespective with the type of particle interactions presumed. The commonly used mixing schemes, correspond to a proper choice of the kinetic and mass matrices, and are derived as special cases. In particular, $\eta$-$\eta '$ mixing, requires one angle, if and only if, the kinetic term with the intrinsic fields has a quadratic form.Comment: REVTeX, 6 page

Mirror matter admixtures in K_L \to \gamma\gamma

Based on possible albeit tiny, admixtures of mirror matter in ordinary mesons we study the K_L \to \gamma\gamma transition. We find that this process can be described with a small SU(3) symmetry breaking of only 3%. We also determine the eta-eta' mixing angle and the pseudoscalar decay constants. The results for these parameters are consistent with some obtained in the literature. They favor two recent determinations; one based on two analytical constraints, and another one based on next-to-leading order power corrections

Informational Lobbying and Political Contributions.

Interest groups can influence political decisions in two distinct ways: by offering contributions to political actors and by providing them with relevant information that is favorable for the group. We analyze the conditions under which interest groups are more inclined to use one or the other channel of influence. First, we identity an indirect cost of searching for information in the form of an information externality that increases the cost of offering contributions. We then show that an extreme interest group might find it beneficial to abandon information provision altogether and instead seek influence solely via contributions. Finally, we apply our model to cast doubt on the "conventional wisdom" that competition among information providers increases the amount of information provided: when the identified information externality is taken into account, we show that competition decreases information search. Thus, our analysis lends support to a rather cynical view of lobbying wherein lobby groups provide little or no useful information to the political process.