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The more dynamic and unpredictable the development constraints, the more agile the development project should be to cope with and utilize inherent change. Especially in such contexts, aligning with the project's mission and vision, committing to next steps, and documenting the development path is challenging. To support the decision making process of self-organized agile development teams with an overview, a recent research paper proposes the Progress Map. The investigation at hand applies the Progress Map in semi-industrial development projects to empirically validate its applicability and performance in the form of a multi-case study. The results indicate that, given future refinements, this instrument can be valuable to plan, document, and communicate the progress of an agile development project.
Laser-based compact MeV X-ray sources are useful for a variety of applications such as radiography and active interrogation of nuclear materials. MeV X rays are typically generated by impinging the intense laser onto ~mm-thick high-Z foil. Here, we have characterized such a MeV X-ray source from 120 TW (80 J, 650 fs) laser interaction with a 1 mm-thick tantalum foil. Our measurements show X-ray temperature of 2.5 MeV, flux of 3 × 1012 photons/sr/shot, beam divergence of ~0.1 sr, conversion efficiency of ~1%, that is, ~1 J of MeV X rays out of 80 J incident laser, and source size of 80 m. Our measurement also shows that MeV X-ray yield and temperature is largely insensitive to nanosecond laser contrasts up to 10−5. Also, preliminary measurements of similar MeV X-ray source using a double-foil scheme, where the laser-driven hot electrons from a thin foil undergoing relativistic transparency impinging onto a second high-Z converter foil separated by 50–400 m, show MeV X-ray yield more than an order of magnitude lower compared with the single-foil results.
As renewable energy supply chains have grown increasingly globalized, national clean energy transitions have become highly influenced by international dynamics. However, these dynamics are themselves collectively shaped by domestic policy that drives the deployment of renewables. While spatial spillovers of domestic renewable energy policies have been studied on an aggregate level regarding policy diffusion or the flows of technology across countries, implications on an actor-level have been largely neglected. This article addresses this gap by analyzing global patterns of market openings for wind, solar PV, and biomass, focusing on the role of private project developers in developing countries. We use a mixed method design, based on a newly merged dataset encompassing eighty countries, and on interviews with pioneering project developers. Results highlight how patterns in market openings are shaped considerably by technology characteristics. Further, empirical results show international private developers are a key first mover in many developing countries. We explore drivers for this internationalization trend, including the impact of international developers' home country policies and the accumulation of tacit knowledge from home country markets for market openings abroad. Finally, we discuss implications for industrial policy and argue for further research on global spillovers of national policies on the actor-level.
Hairworms (Nematomorpha) are a little-known group of parasites, and despite having been represented in the taxonomic literature for over a century, the implementation of molecular genetics in studies of hairworm ecology and evolution lags behind that of other parasitic taxa. In this study, we characterize the genetic diversity of the New Zealand nematomorph fauna and test for genetic structure within the most widespread species found. We provide new mitochondrial and nuclear ribosomal sequence data for three previously described species from New Zealand: Gordius paranensis, Parachordodes diblastus and Euchordodes nigromaculatus. We also present genetic data on a previously reported but undescribed Gordius sp., as well as data from specimens of a new Gordionus sp., a genus new for New Zealand. Phylogenetic analyses of CO1 and nuclear rDNA regions correspond with morphological classification based on scanning electron microscopy, and demonstrate paraphyly of the genus Gordionus and the potential for cryptic species within G. paranensis. Population-level analyses of E. nigromaculatus showed no genetic differentiation among sampling locations across the study area, in contrast to previously observed patterns in known and likely definitive hosts. Taken together, this raises the possibility that factors such as definitive host specificity, intermediate host movement, and passive dispersal of eggs and larvae may influence host–parasite population co-structure in hairworms.
In this paper we study certain sheaves of
-adically complete rings of differential operators on semistable models of the projective line over the ring of integers in a finite extension
. The global sections of these sheaves can be identified with (central reductions of) analytic distribution algebras of wide open congruence subgroups. It is shown that the global sections functor furnishes an equivalence between the categories of coherent module sheaves and finitely presented modules over the distribution algebras. Using the work of M. Emerton, we then describe admissible representations of
in terms of sheaves on the projective limit of these formal schemes. As an application, we show that representations coming from certain equivariant line bundles on Drinfeld’s first étale covering of the
-adic upper half plane are admissible.
This paper discusses the operating range of frequency modulated (FM) radars in the presence of interference. For this purpose, radar- and path loss equations are used to draw the equipotential lines for a given signal-to-interference ratio as a function of the spatial distribution of targets and interferers in order to identify relevant scenario constellations. Further the factors influencing the gain of signal versus deterministic interference are discussed based on measurements and simulations. Finally, the influence of different kinds of interference on the spectrum of a frequency modulated continuous wave radar is shown.
Rigorous finite element optical simulations have been used to examine the absorption of light in various crystalline silicon based, nanostructured solar cell architectures. The compared structures can all be produced on glass substrates using a periodically structured dielectric coating and a combination of electron-beam evaporation of silicon and subsequent solid phase crystallization. A required post-treatment by selective etching of non-compact silicon regions results in an absorber material loss. We show that by adequately tailoring the optical design around the processed silicon layer, the absorptance loss due to material removal can be completely overcome. The resulting silicon structure, which is an array of holes with non-vertical sidewalls, shows promising light path enhancement and features an even higher absorptance than the initial nanodome structure of the unetched absorber.
The use of plasmonic nanoparticles as light scattering elements for light trapping in solar cells is studied. From theoretical considerations it follows that Ag particles with a diameter on the order of 100 nm possess ideal light scattering properties. It is demonstrated that these particles can be fabricated using the selective aerosol deposition technique. Because this newly developed technique provides excellent control over critical parameters such as particle size and surface coverage it is a valuable tool for optimizing plasmonic solar cells. The initial experiments show that embedding Ag particles with a diameter of 180 nm into amorphous silicon solar cells enhances the current output.
Lowrance et al. (2000) found a faint companion candidate about 4 arcsec south of the young A0-type star HR 7329. Its spectral type of M7-8 is consistent with a young brown dwarf companion. Here we report spectroscopic J band observations using the integral field spectrograph SINFONI at VLT, enabling a new estimation of effective temperature, extinction and surface gravity of the object and hence its mass. Although the data were reduced carefully, the presence of a spike within the point spread function of the object in each spectral image hampered the precise estimation of the properties of HR 7329. Nevertheless, we will show with the example of this sub-stellar companion how mass estimates independent of evolutionary models of directly imaged sub-stellar companions can be obtained, after removing most of the strong influence of the spike in the present data, and present a new mass estimation of HR 7329 B/b based on the values gained.
Pyrolytic conversion of preceramic polymers such as polysilanes, -silazanes, or -siloxanes to ceramics may be significantly influenced by the resence of active filler dispersoids. Based on thermodynamic and microstructural considerations a variety of suitable polymer-filler systems can be found which allow the fabrication of microcrystalline composite materials with low dimensional change upon polymer- ceramic conversion. As an example the active filler controlled reaction pyrolysis of polysiloxane with addition of titanium powder was investigated. A composite material with microcrystalline titanium carbide inclusions embedded in an amorphous (< 1000 °C) or nanocrystalline (>1000 °C) silicon oxycarbide matrix was formed. Property changes with increasing pyrolysis temperature can be attributed to various microstructural transformations. Thus, a variety of potential fillers may be used to tailor the microstructure of polymer-derived ceramic composite materials in order to fabricate bulk materials and components with a broad range of compositions and properties.
We present organic field-effect transistors with dihexylquaterthiophene (DH4T) as active material, a derivative of the oligothiophene á-4T with two hexyl chains as end groups. This substitution makes this molecule suitable not only for vacuum sublimation but also for solution processing which enables cheaper production. Additionally, the layer ordering is improved. We compare vacuum deposited and solution processed OFETs based on DH4T. The former ones show nearly ideal I-V characteristics. The latter ones show deviations from ideal behavior and lower currents. Furthermore, temperature dependent measurements of drain-source current in vacuum deposited DH4T-OFETs shows an unusual variation of the OFET apparent mobility. These apparent changes in mobility are caused by a threshold voltage shift, which becomes pronounced at around 290 K
Given a compact p-adic Lie group G over a finite unramified extension L/ℚp let GL/ℚp be the product over all Galois conjugates of G. We construct an exact and faithful functor from admissible G-Banach space representations to admissible locally L-analytic GL/ℚp-representations that coincides with passage to analytic vectors in the case L=ℚp. On the other hand, we study the functor ‘passage to analytic vectors’ and its derived functors over general basefields. As an application we compute the higher analytic vectors in certain locally analytic induced representations.
We have searched for close and faint companions around T Tauri stars in the Chamaeleon star forming region. Two epochs of direct imaging data were taken with the VLT Adaptive Optics instrument NaCo in February 2006 and March 2007 in Ks band for the classical T Tauri star CT Cha together with a Hipparcos binary for astrometric calibration. Moreover a J band image was taken in March 2007 to get color information. We found CT Cha to have a very faint companion (Ks0=14.6 mag) of ∼2.67” separation corresponding to ∼440AU. We show that CT Cha A and the faint object form a common proper motion pair and that the companion is not a non-moving background object (with 4σ significance).
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