Investigation of ionosphere and airglow response to cusp electrons

The objectives are presented to compare and compute ionospheric quantities and airglow emission

Venus internal magnetic field and its interaction with the interplanetary magnetic field

In a previous study, Knudsen et al. suggested that Venus has a weak internal magnetic dipole field of the order of 7 x 10 + 20 G cm(exp -3) that is manifested in the form of magnetic flux tubes threading the ionospheric holes in the Venus nightside ionosphere. They pointed out that any internal field of Venus, dipole or multipole, would be weakened in the subsolar region and concentrated in the antisolar region of the planet by the supersonic transterminator convection of the dayside ionosphere into the nightside hemisphere. The inferred magnitude of the dipole field does not violate the upper limit for an internal magnetic field established by the Pioneer Venus magnetometer experiment. The most compelling objection to the model suggested by Knudsen et al. has been the fact that it does not explain the observed interplanetary magnetic field (IMF) control of the polarity of the ionospheric hole flux tubes. In this presentation I suggest that a magnetic reconnection process analogous to that occurring at earth is occurring at Venus between the IMF and a weak internal dipole field. At Venus in the subsolar region, the reconnection occurs within the ionosphere. At Earth it occurs at the magnetopause. Reconnection will occur only when the IMF has an appropriate orientation relative to that of the weak internal field. Thus, reconnection provides a process for the IMF to control the flux tube polarity. The reconnection in the subsolar region takes place in the ionosphere as the barrier magnetic field is transported downward into the lower ionosphere by downward convection of ionospheric plasma and approaches the oppositely directed internal magnetic field that is diffusing upward. The reconnected flux tubes are then transported anti-Sunward by the anti-Sunward convecting ionospheric plasma as well as by the anti-Sunward-flowing solar wind. Reconnection will also occur in the Venus magnetic tail region, somewhat analogously to the reconnection that occurs in the magnetotail of the Earth. The possibility that reconnection is occurring between the IMF and an internal dipole field may be tested by measuring the orientation of the IMF projected into a plane perpendicular to the solar wind velocity during time intervals for which ionospheric holes are observed. The orientations of the IMV components should fall within a 180 deg angle

Intra and Inter-Organizational Knowledge Transfer Processes Identifying the Missing Links

Inspired by the resource- and knowledge-based views, much attention has been focused on knowledge transfer as a process of strategic importance. Still, many open questions regarding knowledge transfer processes need to be addressed to complete our understanding. For instance, what are the barriers to knowledge transfer, and what are the facilitators? A review of the literature reveals that it is divided into two streams: articles on intra-firm knowledge flows and articles on inter-firm knowledge flows. Part of the incompleteness of our understanding of knowledge transfer processes, we argue, derives from the fact that it is unclear in which way intra- and inter-firm knowledge flows are different. The paper investigates three questions: first, how knowledge transfer is defined differently in intra- and inter-firm knowledge flows; second: how barriers to knowledge transfer processes differ; and thirdly: what we need to know to be able to formulate a management view of organizational knowledge flows, whether intra- or inter-organizational. The concluding section argues five research questions whose answers may enable research to formulate a management view of knowledge flows.Review; internal knowledge flows; external knowledge flows; definition; barriers to knowledge flows

Discontinuity induced bifurcations of non-hyperbolic cycles in nonsmooth systems

We analyse three codimension-two bifurcations occurring in nonsmooth systems, when a non-hyperbolic cycle (fold, flip, and Neimark-Sacker cases, both in continuous- and discrete-time) interacts with one of the discontinuity boundaries characterising the system's dynamics. Rather than aiming at a complete unfolding of the three cases, which would require specific assumptions on both the class of nonsmooth system and the geometry of the involved boundary, we concentrate on the geometric features that are common to all scenarios. We show that, at a generic intersection between the smooth and discontinuity induced bifurcation curves, a third curve generically emanates tangentially to the former. This is the discontinuity induced bifurcation curve of the secondary invariant set (the other cycle, the double-period cycle, or the torus, respectively) involved in the smooth bifurcation. The result can be explained intuitively, but its validity is proven here rigorously under very general conditions. Three examples from different fields of science and engineering are also reported

Subdivisional spaces and graph braid groups

We study the problem of computing the homology of the configuration spaces of a finite cell complex $X$. We proceed by viewing $X$, together with its subdivisions, as a subdivisional space--a kind of diagram object in a category of cell complexes. After developing a version of Morse theory for subdivisional spaces, we decompose $X$ and show that the homology of the configuration spaces of $X$ is computed by the derived tensor product of the Morse complexes of the pieces of the decomposition, an analogue of the monoidal excision property of factorization homology. Applying this theory to the configuration spaces of a graph, we recover a cellular chain model due to \'{S}wi\k{a}tkowski. Our method of deriving this model enhances it with various convenient functorialities, exact sequences, and module structures, which we exploit in numerous computations, old and new.Comment: 71 pages, 15 figures. Typo fixed. May differ slightly from version published in Documenta Mathematic

Essays on the Economics of Information in Auctions

Informational assumptions are an important aspect of the study of auctions in economictheory. However, there has been limited research into how the assumptions made by theoristsimpact their results. I explore two different aspects of the information available to biddersin auctions. The information that is important to the theoretical study of auctions can bedivided into two types. First, there is information about the realized values of the bidders.I explore this through a model of an English auction with interdependent values wherebidders are able to acquire the private information that is realized by other bidders. Ifind that the ability to costlessly acquire additional information about competitors does notimpact the efficiency of the English auction. This is in line with other research into thistype of information acquisition. I also briefly explore the revenue implications of biddersbeing able to acquire this type of information. The second type of information is about theoverall structure from which the bidders values are drawn. In most theoretical treatmentsof auctions, it is assumed that bidders know this overall structure. I begin to relax thisassumption by adding a small amount of uncertainty about the structure of one of thebidders valuation functions in auctions with interdependent values. Here I find that boththe English auction and the second price auction are no longer efficient after the changein informational structure. I use data collected through economic experiments to test thetheoretical predictions of this model and find that the English auction is more efficient bothwith the standard informational assumptions and with the change made in the informationalstructure. Both of these results suggest that the open format of an English auction, whereinformation is revealed over the course of the auction, may mean that theoretical resultswith stronger assumptions about informational structures at the beginning of the auctionare somewhat robust to those assumptions

The lost sunspot cycle: New support from Be10 measurements

It has been suggested that the deficit in the number of spots on the surface of the Sun between 1790 and 1830, known as the Dalton minimum, contained an extra cycle that was not identified in the original sunspot record by Wolf. Though this cycle would be shorter and weaker than the average solar cycle, it would shift the magnetic parity of the solar magnetic field of the earlier cycles. This extra cycle is sometimes referred to as the 'lost solar cycle' or 'cycle 4b'. Here we reanalyse Be10 measurements with annual resolution from the NGRIP ice core in Greenland in order to investigate if the hypothesis regarding a lost sunspot cycle is supported by these measurements. Specifically, we make use of the fact that the Galactic cosmic rays, responsible for forming Be10 in the Earth's atmosphere, are affected differently by the open solar magnetic field during even and odd solar cycles. This fact enables us to evaluate if the numbering of cycles earlier than cycle 5 is correct. For the evaluation, we use Bayesian analysis, which reveals that the lost sunspot cycle hypothesis is likely to be correct. We also discuss if this cycle 4b is a real cycle, or a phase catastrophe, and what implications this has for our understanding of stellar activity cycles in general.Comment: accepted for publication in A&

Policy instruments in the Common Agricultural Policy

Policy changes in the Common Agricultural Policy (CAP) can be explained in terms of the exhaustion and long-term contradictions of policy instruments. Changes in policy instruments have reoriented the policy without any change in formal Treaty goals. The social and economic efficacy of instruments in terms of evidence-based policy analysis was a key factor in whether they were delegitimized. The original policy instruments were generally dysfunctional, but reframing the policy in terms of a multifunctionality paradigm permitted the development of more efficacious instruments. A dynamic interaction takes place between the instruments and policy informed by the predominant discourses