Balanced-bellows spirometer

Compact balanced-bellows dry type spirometer was designed to be insensitive to acceleration fields along any or all coordinate axes. It provides true indication of respiratory action of test subject without need for calibration in acceleration fields

Entrepreneurial intentions among students: towards a re-focused research agenda

Purpose – This paper aims to address the need for a re-focused research agenda in relation to graduate entrepreneurship. An important theme for some years has been the effort to monitor attitudes and intentions of students towards starting up their own businesses. It is timely, however, to raise some questions about both the impact of this research and likewise the general approach it has taken in understanding the phenomenon of graduate entrepreneurship. Design/methodology/approach – The paper draws on a large data set (over 8,000 students) from one UK region. Specifically, it presents data from the 2007/2008 Entrepreneurial Intentions (EI) survey within the Yorkshire and Humberside region and reflects back over previous iterations of this research. Findings – The paper identifies three key outcomes. First, it establishes that across all years of the survey a substantial minority of students consistently hold relatively strong start-up intentions. Second, the paper highlights that, despite considerable efforts to increase the numbers moving to start-up, little impact is discernible. Third, the paper suggests that, although the EI survey is useful as a stock-taking exercise, it fails to address critical questions around the impact of higher education on entrepreneurship and the transition from entrepreneurial intent to the act of venture creation. Originality/value – The paper provides an important positioning perspective on the relationship between higher education and graduate entrepreneurship. While highlighting the importance of the EI research, the paper establishes the need for a re-focused research agenda; one that is conceptually robust and with a focus on the student journey from higher education to graduate entrepreneur

The algebro-geometric initial value problem for the Ablowitz-Ladik hierarchy

We discuss the algebro-geometric initial value problem for the Ablowitz-Ladik hierarchy with complex-valued initial data and prove unique solvability globally in time for a set of initial (Dirichlet divisor) data of full measure. To this effect we develop a new algorithm for constructing stationary complex-valued algebro-geometric solutions of the Ablowitz-Ladik hierarchy, which is of independent interest as it solves the inverse algebro-geometric spectral problem for general (non-unitary) Ablowitz-Ladik Lax operators, starting from a suitably chosen set of initial divisors of full measure. Combined with an appropriate first-order system of differential equations with respect to time (a substitute for the well-known Dubrovin-type equations), this yields the construction of global algebro-geometric solutions of the time-dependent Ablowitz-Ladik hierarchy. The treatment of general (non-unitary) Lax operators associated with general coefficients for the Ablowitz-Ladik hierarchy poses a variety of difficulties that, to the best of our knowledge, are successfully overcome here for the first time. Our approach is not confined to the Ablowitz-Ladik hierarchy but applies generally to (1+1)-dimensional completely integrable soliton equations of differential-difference type.Comment: 47 page

The Double Slit Experiment With Polarizers

The double slit experiment provides a standard way of demonstrating how quantum mechanics works. We consider modifying the standard arrangement so that a photon beam incident upon the double slit encounters a polarizer in front of either one or both of the slits.Comment: 6 page

Measuring the Compactness of Political Districting Plans

The United States Supreme Court has long recognized compactness as an important principle in assessing the constitutionality of political districting plans. We propose a measure of compactness based on the distance between voters within the same district relative to the minimum distance achievable -- which we coin the relative proximity index. We prove that any compactness measure which satisfies three desirable properties (anonymity of voters, efficient clustering, and invariance to scale, population density, and number of districts) ranks districting plans identically to our index. We then calculate the relative proximity index for the 106th Congress, requiring us to solve for each state's maximal compactness; an NP-hard problem. Using two properties of maximally compact districts, we prove they are power diagrams and develop an algorithm based on these insights. The correlation between our index and the commonly-used measures of dispersion and perimeter is -.22 and -.06, respectively. We conclude by estimating seat-vote curves under maximally compact districts for several large states. The fraction of additional seats a party obtains when their average vote increases is significantly greater under maximally compact districting plans, relative to the existing plans.

Multitasking, Learning, and Incentives: A Cautionary Tale

We develop a multi-period, multi-task principal-agent model in which neither the principal nor the agent knows the mapping from actions to outputs. The agent can learn about the production function over time by exerting effort and observing output. The model has a stark prediction: incentives may have a negative impact on agent effort if, by exerting effort, they learn their ability is lower than their prior beliefs. To provide evidence on the model’s predictions, we conduct a field experiment in fifty Houston public schools, where students, parents, and teachers were rewarded with financial incentives. The experimental data is consistent with the model’s most distinguishing predictions, though other explanations are possible.

Design at a distance

The Open University has been teaching design at a distance for three decades. In this time delivery mechanisms have changed from non-interactive broadcasts to interactive media. A new generation of courses is emerging taught entirely online. This offers many challenges and opportunities This paper describes three tools that will be used in a new, level 1 course. Knowledge mapping, animated screen capture and an online studio space, OpenDesignStudio, which is a development of the Flickr photo-sharing interface. The advantage of the almost ubiquitous use of Web2 technologies is that students are communicating more and the potential for these technologies to support collaborative work in a learning environment is growing. The paper also discusses how assessment strategies might be re-considered to recognise and credit students who are increasingly using web resources to aid and augment their learning. The use of knowledge maps offers a way for students to bring together the materials they find for assessment tasks in one place and to relate and link those materials together. The use of animated screen capture offers the opportunity to present ideas and reflect upon process at a distance and hone communication and presentation skills. The online studio allows for peer support and review in text and audio-visually and also provides an arena in which the tutor can check on progress and offer individual advice at a distance