Solar and Galactic Cosmic Rays observed by SOHO

Both the Cosmic Ray Flux (CRF) and Solar Energetic Particles (SEPs) have left an imprint on SOHO technical systems. While the solar array efficiency degraded irreversibly down to ~77% of its original level over roughly 1 1/2 solar cycles, Single Event Upsets (SEUs) in the solid state recorder (SSR) have been reversed by the memory protection mechanism. We compare the daily CRF observed by the Oulu station with the daily SOHO SEU rate and with the Degradation curve of the solar arrays. The Oulu CRF and the SOHO SSR SEU rate are both modulated by the solar cycle and are highly correlated, except for sharp spikes in the SEU rate, caused by isolated SEP events, which also show up as discontinuities in the otherwise slowly decreasing solar ray efficiency. This allows to discriminate between effects with solar and non-solar origin and to compare the relative strength of both. We find that during solar cycle 23 (1996 Apr 1 -- 2008 Aug 31) only 6% of the total number of SSR SEUs were caused by SEPs; the remaining 94% were due to galactic cosmic rays. During the maximum period of cycle 23 (2000 Jan 1 -- 2003 Dec 31), the SEP contribution increased to 22%, and during 2001, the year with the highest SEP rate, to 30%. About 40% of the total solar array degradation during the 17 years from Jan 1996 through Feb 2013 can be attributed to proton events, i.e. the effect of a series of short-lived, violent SEP events is comparable to the cycle-integrated damage by cosmic rays.Comment: 10 pages, 5 figures accepted for publication in Cent. Eur. Astrophys. Bul

Optimal Simple Rules for Fiscal Policy in a Monetary Union

The paper discusses the stabilizing potential of fiscal policy in a dynamic general-equilibrium model of monetary union. We consider a small open economy inside the currency area. We analyze the demand and supply effects of direct taxation, indirect taxation and government spending and derive optimal simple rules for fiscal stabilization of a technology shock. Fiscal policy achieves substantial macroeconomic stabilization. Simple public-expenditure rules show the highest degree of both output and inflation stabilization. The implementation lag substantially weakens output stabilization, but hardly affects the stabilization of prices. Out-put-oriented rules imply less instrument inertia than inflation-dominated rules. The implemen-tation lag leads to higher coefficients for inflation relative to output in the optimal rule. Com-pared to the single-instrument approach the simultaneous optimization of two instrument rules implies only little additional stabilization gains.Fiscal policy, monetary union, simple policy rules

Semantic Tagging on Historical Maps

Tags assigned by users to shared content can be ambiguous. As a possible solution, we propose semantic tagging as a collaborative process in which a user selects and associates Web resources drawn from a knowledge context. We applied this general technique in the specific context of online historical maps and allowed users to annotate and tag them. To study the effects of semantic tagging on tag production, the types and categories of obtained tags, and user task load, we conducted an in-lab within-subject experiment with 24 participants who annotated and tagged two distinct maps. We found that the semantic tagging implementation does not affect these parameters, while providing tagging relationships to well-defined concept definitions. Compared to label-based tagging, our technique also gathers positive and negative tagging relationships. We believe that our findings carry implications for designers who want to adopt semantic tagging in other contexts and systems on the Web.Comment: 10 page

Impacts of environmental regulations on the efficiency of arable farms in France and Germany

This paper develops a methodology for asymmetric treatment of desirable and undesirable outputs. First, a hyperbolic output efficiency measurement is used to describe a middle term transformation of production processes where producers try to improve their competitiveness together with a reduction of the negative impact on the environment. Second, a radial efficiency measurement, called directional output distance function, is used to depict a long-term transformation of the production process. A non-parametric Data Envelopment Analysis (DEA) and a Stochastic Frontier Analysis (SFA) are used to evaluate the impact of agricultural policy changes, both in France and Germany, on the technical and environmental efficiency of arable farms, taking into account participation or not in agri-environmental programs. The results from both methods indicate only limited possibilities for environmental improvements, mainly for farms participating in agri-environmental programs.Frontier analysis, technical and environmental efficiency, environmental regulations, Agricultural and Food Policy, Environmental Economics and Policy, Productivity Analysis,

Zum Vorkommen des Haubentauchers (Podiceps cristatus) im westlichen Niedersachsen

Es wird ein Überblick über das Vorkommen des Haubentauchers (Podiceps cristatus) im westlichen Niedersachsen (ehem. Reg.-Bez. Osnabrück und Randgebiete) gegeben. 1984 wurde eine vollständige Brutbestandserfassung angestrebt, während für die Vorjahre eine Auswertung der zahlreichen Einzelbeobachtungen erfolgte. Die Zählung 1984 ergab einen Gesamtbestand von ca. 440 Paaren auf 43 Gewässern. Es werden Hinweise zum Habitat, zur Phänologie und Brutbiologie gegeben. Außerdem werden die möglichen Ursachen der Bestandszunahme diskutiert. Die Brutbestandserfassungen sollen fortgesetzt und das vorliegende Datenmaterial vervollständigt werden

Employment regulation and labor market policy in Germany, 1991 - 2005

The paper provides an overview of institutional provisions and reforms regarding employment protection, active and passive labor market policies in Germany as well as of actors' responsibilities in these areas. It covers the period between the early 1990s and the most recent Hartz reforms. Empirical data on labor market outcomes with respect to the levels and structures of both employment and unemployment complements this study

Subsumption algorithms for concept languages

We investigate the subsumption problem in logic-based knowledge representation languages of the KL-ONE family and give decision procedures. All our languages contain as a kernel the logical connectives conjunction, disjunction, and negation for concepts, as well as role quantification. The algorithms are rule-based and can be understood as variants of tableaux calculus with a special control strategy. In the first part of the paper, we add number restrictions and conjunction of roles to the kernel language. We show that subsumption in this language is decidable, and we investigate sublanguages for which the problem of deciding subsumption is PSPACE-complete. In the second part, we amalgamate the kernel language with feature descriptions as used in computational linguistics. We show that feature descriptions do not increase the complexity of the subsumption problem