Towards rule-based visual programming of generic visual systems

This paper illustrates how the diagram programming language DiaPlan can be used to program visual systems. DiaPlan is a visual rule-based language that is founded on the computational model of graph transformation. The language supports object-oriented programming since its graphs are hierarchically structured. Typing allows the shape of these graphs to be specified recursively in order to increase program security. Thanks to its genericity, DiaPlan allows to implement systems that represent and manipulate data in arbitrary diagram notations. The environment for the language exploits the diagram editor generator DiaGen for providing genericity, and for implementing its user interface and type checker.Comment: 15 pages, 16 figures contribution to the First International Workshop on Rule-Based Programming (RULE'2000), September 19, 2000, Montreal, Canad

Array Size Reduction for High-Rank LOS MIMO ULAs

In this paper we propose an extended LOS MIMO channel model, which considers an additional phase shifting term in the transmission path, and which provides the potential to improve channel conditioning significantly. We show that this phase shifting can, for example, be achieved by adding a dielectric material between the transmitting and receiving antennas, where the phase shift is dependent on the distance the waves travel in the medium. Using that distance as a design parameter we demonstrate that the optimal spacing between antenna elements of uniform linear arrays, achieving full spatial multiplexing, can be reduced compared with the well-known spacing criterion from previous investigations.Comment: Submitted to IEEE Wireless Communications Letter

The LIOn's share: How the Liberal International Order Contributes to its Own Legitimacy Crisis. Harvard CES Open Forum Series2019-2020

The liberal international order (LIO) is experiencing a legitimacy crisis in its Western heartland. What causes this crisis? Existing approaches focus on the LIO’s unequal allocation of wealth and values that produces losers and thus breeds dissatisfaction. Yet, why this dissatisfaction translates into a delegitimation of the order rather than a contestation over policies remains unaccounted for. Complementing the cultural and economic backlash hypotheses, this paper advances an institutionalist explanationfor the current crisis of the LIO, which accounts for the growing resistance to the LIO with a political backlash hypothesis. Our argument is that the institutional characteristics of the LIO’s political order trigger self-undermining processes by inciting opposition that cannot be politically accommodated and is thus bound to turn into polity contestation. In particular, we hold that IOs’ predominantly technocratic legitimation rationale on the one hand, and their increasing political authority with distributional effects on the other, create a democracy gap. It implies that avenues to absorb opposition through input channels are largely missing and thus incite the erosion of the LIO’s general acceptance. We illustrate the plausibility of this argument with evidence from the European Union (EU) as well as the international regimes on trade and human rights

The mean king's problem: Prime degrees of freedom

We show how one can ascertain the values of a complete set of mutually complementary observables of a prime degree of freedom.Comment: Originally submitted to Physical Review Letters; updated version now submitted to Physics Letters

Determinacy Through Intertemporal Capital Adjustment Costs

It is well known that if mild sector–specific externalities are considered, then the steady state of the standard two-sector real business cycle model can become locally indeterminate and endogenous business cycles can arise. We show that this result is not robust to the introduction of standard intertemporal capital adjustment costs, which may accrue when total capital is adjusted or when each sector’s capital is adjusted. We find for both forms of adjustment costs that the steady state is determinate for all empirically plausible parameter values. We also find that determinacy occurs for a much larger range of parameter values when adjusting each sector’s capital is costly.capital adjustment costs; determinacy; local indeterminacy; local stability; sector-specific externality