Electronics and Chemistry: Varying Single Molecule Junction Conductance Using Chemical Substituents

We measure the low bias conductance of a series of substituted benzene diamine molecules while breaking a gold point contact in a solution of the molecules. Transport through these substituted benzenes is by means of nonresonant tunneling or superexchange, with the molecular junction conductance depending on the alignment of the metal Fermi level to the closest molecular level. Electron-donating substituents, which drive the occupied molecular orbitals up, increase the junction conductance, while electron-withdrawing substituents have the opposite effect. Thus for the measured series, conductance varies inversely with the calculated ionization potential of the molecules. These results reveal that the occupied states are closest to the gold Fermi energy, indicating that the tunneling transport through these molecules is analogous to hole tunneling through an insulating film.Comment: 14 pages, 4 figure

If the Alliance Fits . . . : Innovation and Network Dynamics

Network formation is often said to be driven by social capital considerations. A typical pattern observed in the empirical data on strategic alliances is that of small world networks: dense subgroups of firms interconnected by (few) clique-spanning ties. The typical argument is that there is social capital value both to being embedded in a dense cluster, and to bridging disconnected clusters. In this paper we develop and analyze a simple model of joint innovation where we are able to reproduce these features, based solely on the assumption that successful partnering demands some intermediate amount of similarity between the partners.Network formation, Strategic alliances, Knowledge portfolios, Knowledge transfer

If the Alliance Fits . . . : Innovation and Network Dynamics.

Network formation is often said to be driven by social capital considerations. A typical pattern observed in the empirical data on strategic alliances is that of small world networks: dense subgroups of firms interconnected by (few) clique-spanning ties. The typical argument is that there is social capital value both to being embedded in a dense cluster, and to bridging disconnected clusters. In this paper we develop and analyze a simple model of joint innovation where we are able to reproduce these features, based solely on the assumption that successful partnering demands some intermediate amount of similarity between the partners.

Voter involvement, fiscal autonomy and public sector efficiency: evidence from German municipalities

Social and/or political involvement within the population is often argued to enhance public sector performance. The underlying idea is that engagement fosters political awareness and interest and increases the public’s monitoring ability. Still, weak fiscal autonomy can undermine voters’ interest in and demand for an efficient production of public services. In our contribution, we test whether and how voter involvement in the political sphere is related to government performance – in terms of its efficiency – using a broad panel of German municipalities. Our results suggest that voter involvement indeed has a positive impact on cost efficiency. Crucially, however, this efficiency-enhancing effect of voter involvement is significantly positively affected by local governments’ fiscal autonomy. -- Häufig wird argumentiert, dass eine soziale und politische Beteiligung der Bevölkerung die Effizienz des öffentlichen Sektors fördert. Die grundlegende Idee ist, dass dieses Engagement politisches Bewusstsein und Interesse fördert und somit die Möglichkeiten der Öffentlichkeit zur Kontrolle erhöht. Allerdings untergräbt eine schwache Finanzhoheit das Interesse der Wähler und ihre Nachfrage nach einer effizienten Produktion öffentlicher Leistungen. In unserem Beitrag testen wir anhand eines breiten Panels deutscher Kommunen, ob und wie die Beteiligung von Wählern in der politischen Sphäre im Zusammenhang zum Leistungsverhalten einer Regierung – im Hinblick auf Effizienz – steht. Unsere Ergebnisse deuten darauf, dass sich die Beteiligung der Wähler tatsächlich positiv auf die Kosteneffizienz auswirkt. Entscheidend ist jedoch, dass dieser Effizienzfördernde Effekt der Wählerbeteiligung signifikant positiv von der Finanzautonomie der kommunalen Regierungen beeinflusst wird.Civic engagement,fiscal autonomy,local government,efficiency,stochastic,frontier analysis,German municipalities

Autonomous 3D Exploration of Large Structures Using an UAV Equipped with a 2D LIDAR

This paper addressed the challenge of exploring large, unknown, and unstructured industrial environments with an unmanned aerial vehicle (UAV). The resulting system combined well-known components and techniques with a new manoeuvre to use a low-cost 2D laser to measure a 3D structure. Our approach combined frontier-based exploration, the Lazy Theta* path planner, and a flyby sampling manoeuvre to create a 3D map of large scenarios. One of the novelties of our system is that all the algorithms relied on the multi-resolution of the octomap for the world representation. We used a Hardware-in-the-Loop (HitL) simulation environment to collect accurate measurements of the capability of the open-source system to run online and on-board the UAV in real-time. Our approach is compared to different reference heuristics under this simulation environment showing better performance in regards to the amount of explored space. With the proposed approach, the UAV is able to explore 93% of the search space under 30 min, generating a path without repetition that adjusts to the occupied space covering indoor locations, irregular structures, and suspended obstaclesUnión Europea Marie Sklodowska-Curie 64215Unión Europea MULTIDRONE (H2020-ICT-731667)Uniión Europea HYFLIERS (H2020-ICT-779411

Determinants of globalization and growth prospects for Sub-Saharan African countries

Over the decades leading to the global financial crisis, the world witnessed a deepening integration of world economies, irrespective of a country’s geographical location on the spherical space. This process of increasing interdependence of world economies, most notably illustrated by the scale of financial flows and movements of goods and services now termed globalization, has been facilitated by research and development and advances in technology, especially in the area of information and communication technology. In spite of its global nature, its expected benefits have not been uniformly distributed, however. This paper shows that the countries and regions that are driving the process of knowledge creation and production of high-tech and manufactured goods, building on frontier technology, are benefiting the most from globalization, increasingly acting as drivers and relegating Sub-Saharan Africa to the end-user status. In this process, the income gap between Sub-Saharan Africa and the globalizers has increased even more. However, the paper also shows that raising the level of technological endowment in Sub-Saharan Africa to that of developed countries could go a long way to bridge Africa's output gaps and improve its export performance in the new globalization landscape of the post-financial crisis era.Debt Markets,Emerging Markets,Economic Theory&Research,Currencies and Exchange Rates,

Multi-GPU Graph Analytics

We present a single-node, multi-GPU programmable graph processing library that allows programmers to easily extend single-GPU graph algorithms to achieve scalable performance on large graphs with billions of edges. Directly using the single-GPU implementations, our design only requires programmers to specify a few algorithm-dependent concerns, hiding most multi-GPU related implementation details. We analyze the theoretical and practical limits to scalability in the context of varying graph primitives and datasets. We describe several optimizations, such as direction optimizing traversal, and a just-enough memory allocation scheme, for better performance and smaller memory consumption. Compared to previous work, we achieve best-of-class performance across operations and datasets, including excellent strong and weak scalability on most primitives as we increase the number of GPUs in the system.Comment: 12 pages. Final version submitted to IPDPS 201