The New Keynesian Phillips Curve with Myopic Agents

Empirical estimations of the New Keynesian Phillips curve support hybrid versions with a positive weight on lagged infl ation and a weight less than one on expected infl ation. We argue that myopic price setting of some agents explains the low weight on expected infl ation. The lagged term can be explained by trend extrapolation if information about the future is costly. In a laboratory experiment we implement the Calvo (1983) microfoundations of the Phillips curve. Both of our hypotheses are supported by the experimental data. About half of the subjects set optimal Calvo prices while about a third is myopic.Hybrid Phillips curve; experimental economics; myopia; behavioral macroeconomics

Interpreting CP Asymmetries in B->pi+ pi- Decays

We discuss methods used to interpret the measurements of CP-asymmetry in B->pi+pi- within the framework of the Standard Model. Interpretations using various theoretical inputs are given, ranging from the rather general, yet unpredictive, properties based on strong isospin symmetry to highly predictive calculations using QCD Factorization. The calculations are performed using the software package CKMFitter and a frequentist method, Rfit.Comment: Invited talk at the Workshop on the CKM Unitarity Triangle, IPPP Durham, April 2003 (eConf C0304052). 4 pages LaTeX, 4 eps figure

Is ‘Renewable Energy’ a Myth? A Comparison between Muscle Work and Agrofuel Energy in Agricultural Production

This study emerges from the rising concern that the now widespread faith in renewable energy systems—as a way to deal with the ecological crisis—may be unfounded. Drawing on inspiration from the global peasant movement Via Campesina and their hypothesis that small-scale agriculture is a strategy for “cooling down the Earth”, this study seeks to discuss the reasons for the widespread belief in renewable energy systems based on how they differ from animate energy systems that have proven successful in the past. As a basis for discussion, the energy efficiency—measured in “energy return on energy investment” (EROI)—of a traditional agricultural system driven by muscle work is compared to the energy efficiency of a modern day agriculture driven by agrofuel. The results show that the energy efficiency of a traditional agriculture driven by muscle work is ten times more energy efficient than modern day agriculture driven by agrofuel. With the theory of techno-fetishism and the concept of ecologically unequal exchange it is argued that agrofuels may be a mechanism for capital accumulation by the unequal exchange of energy dispersion in the world economy. In contrast, traditional small-scale agriculture driven by muscle work may be a promising energetic foundation for local societies and a potential healing strategy for environmental justice, based on its ability to accumulate biomass on Earth. Finally, drawing on these results and discussions, this study critically analyses the principally Western beliefs that underscores the global installation of renewable energy systems as a valid strategy for a just and sustainable future

Enhanced Quality of Experience Based on Enriched Network Centric and Access Control Mechanisms

In the digital world service provisioning in user satisfying quality has become the goal of any content or network provider. Besides having satisfied and therefore, loyal users, the creation of sustainable revenue streams is the most important issue for network operators [1], [2], [3]. The motivation of this work is to enhance the quality of experience of users when they connect to the Internet, request application services as well as to maintain full service when these users are on the move in WLAN based access networks. In this context, the aspect of additional revenue creation for network operators is considered as well. The enhancements presented in this work are based on enriched network centric and access control mechanisms which will be achieved in three different areas of networks capabilities, namely the network performance, the network access and the network features themselves. In the area of network performance a novel authentication and authorisation method is introduced which overcomes the drawback of long authentication time in the handover procedure as required by the generic IEEE 802.1X process using the EAP-TLS method. The novel sequential authentication solution reduces the communication interruption time in a WLAN handover process of currently several hundred milliseconds to some milliseconds by combining the WPA2 PSK and the WPA2 EAP-TLS. In the area of usability a new user-friendly hotspot registration and login mechanisms is presented which significantly simplifies how users obtain WLAN hotspot login credentials and logon to a hotspot. This novel barcode initiated hotspot auto-login solution obtains user credentials through a simple SMS and performs an auto-login process that avoids the need to enter user name and password on the login page manually. In the area of network features a new system is proposed which overcomes the drawback that users are not aware of the quality in which a service can be provided prior to starting the service. This novel graceful denial of service solution informs the user about the expected application service quality before the application service is started

Renewing power : Including global asymmetries within the system boundaries of solar photovoltaic technology

Solar photovoltaic (PV) technology is one of the most favored means of mitigating climate change. At the same time, there is a growing concern over how this technology is both environmentally harmful and unevenly distributed in the world economy. Researchers and environmentalists differ on whether a global relation of power is inherent in solar technology. This thesis investigates to what extent the global, social and material conditions of solar PV technology contrast with conventional conceptions of it. Building on insights from ecological economics and the philosophy of technology, it offers an interdisciplinary approach to solar PV technology. Its central question is whether ‘ecologically unequal exchange’ is a necessary condition for large-scale solar PV development. The theory of ecologically unequal exchange explains how wealthier nations rely on net imports of resources to sustain their levels of consumption and technological development, while displacing much of their work and environmental loads to poorer nations. This theory is tested in an LCA-based account of ecologically unequal exchange between Germany and China during the emergence of the global solar PV market (2002-2018). It is also tested through an application of the concept of ‘power density’ to four leading solar nation’s PV ambitions (China, Germany, India, Italy). The findings demonstrate how large-scale development of solar PV technology may require global asymmetries as much as polysilicon, electrical components, engineers, or direct sunshine. To the extent that decision-makers disregard this, it may be a symptom of ‘machine fetishism,’ which masks the global asymmetries of the emerging energy regime while also preventing us from grasping what modern technology ultimately is

Spherical maximal functions and fractal dimensions of dilation sets

For the spherical mean operators $\mathcal{A}_t$ in $\mathbb{R}^d$, $d\ge 2$, we consider the maximal functions $M_Ef =\sup_{t\in E} |\mathcal{A}_t f|$, with dilation sets $E\subset [1,2]$. In this paper we give a surprising characterization of the closed convex sets which can occur as closure of the sharp $L^p$ improving region of $M_E$ for some $E$. This region depends on the Minkowski dimension of $E$, but also other properties of the fractal geometry such the Assouad spectrum of $E$ and subsets of $E$. A key ingredient is an essentially sharp result on $M_E$ for a class of sets called (quasi-)Assouad regular which is new in two dimensions.Comment: 30 pages, 3 figures. Slightly improved Theorem 1.

Lebesgue space estimates for spherical maximal functions on Heisenberg groups

We prove $L^p\to L^q$ estimates for local maximal operators associated with dilates of codimension two spheres in Heisenberg groups; these are sharp up to two endpoints. The results can be applied to improve currently known bounds on sparse domination for global maximal operators. We also consider lacunary variants, and extensions to M\'etivier groups.Comment: 29 pages, 1 figur

Spherical maximal operators on Heisenberg groups: Restricted dilation sets

Consider spherical means on the Heisenberg group with a codimension two incidence relation, and associated spherical local maximal functions $M_Ef$ where the dilations are restricted to a set $E$. We prove $L^p\to L^q$ estimates for these maximal operators; the results depend on various notions of dimension of $E$.Comment: 27 pages, 1 figur

Endpoint sparse domination for classes of multiplier transformations

We prove endpoint results for sparse domination of translation invariant multiscale operators. The results are formulated in terms of dilation invariant classes of Fourier multipliers based on natural localized $M^{p\to q}$ norms which express appropriate endpoint regularity hypotheses. The applications include new and optimal sparse bounds for classical oscillatory multipliers and multi-scale versions of radial bump multipliers.Comment: 55 pages, 1 figur

Bochner-Riesz means at the critical index: Weighted and sparse bounds

We consider Bochner-Riesz means on weighted $L^p$ spaces, at the critical index $\lambda(p)=d(\frac 1p-\frac 12)-\frac 12$. For every $A_1$-weight we obtain an extension of Vargas' weak type $(1,1)$ inequality in some range of $p>1$. To prove this result we establish new endpoint results for sparse domination. These are almost optimal in dimension $d=2$; partial results as well as conditional results are proved in higher dimensions. For the means of index $\lambda_*=\frac{d-1}{2d+2}$ we prove fully optimal sparse bounds.Comment: 39 pages, 1 figur