281 research outputs found
Kooperationen zwischen etabliertem Mittelstand und Start-ups
Die vorliegende Studie untersucht anhand von Experteninterviews die Motive, Formen sowie Herausforderungen und Erfolgsfaktoren von Kooperationen zwischen etablierten MittelstĂ€ndlern und Start-ups. WĂ€hrend sich Start-ups durch die Kooperation den Zugang zu einem groĂen Netzwerk sowie branchenspezifisches Know-how erhoffen, motiviert MittelstĂ€ndler der Zugang zu neuen Technologien und hochqualifizierten FachkrĂ€ften. Die Wahl der konkreten Kooperationsform leitet sich aus den jeweiligen Zielen ab. Dabei unterscheiden sich Kooperationen hinsichtlich ihrer IntensitĂ€t sowie in ihrer juristischen Ausgestaltung. Damit beide Seiten erfolgreich zusammenkommen, sollte sich das Start-up bereits im Vorfeld mit den BedĂŒrfnissen des potenziellen Kooperationspartners auseinandersetzen. Etablierte MittelstĂ€ndler sollten hingegen ihr stark ausgeprĂ€gtes Sicherheitsdenken ablegen und eine innovationsfreundliche Kultur im Unternehmen etablieren. Insgesamt bietet die Zusammenarbeit fĂŒr beide Seiten ein groĂes Potenzial. Dabei profitiert das Start-up von einer effizienten Zusammenarbeit durch kurze Entscheidungswege in den inhabergefĂŒhrten Unternehmen und der etablierte Mittelstand von einer höheren WettbewerbsfĂ€higkeit durch die Innovationsimpulse der Start-ups.The study examines motives, forms, challenges and success factors of cooperations between start-ups and established Mittelstand firms. While start-ups are motivated by network access and industry-specific knowledge, established firms seek access to new technologies and to highly qualified specialists. The chosen cooperation design derives from the partners' objectives and differs in terms of intensity and legal structure. To initiate a successful cooperation, established firms have to be open-minded and need to establish a risk- and innovation-friendly culture within their organization. Start-ups should already understand the specific needs of their potential partner in advance. Overall these cooperations offer great potential for both sides. Start-ups benefit from the short decision-making processes in owner-managed firms and established firms from higher competitiveness through the innovation impulses they receive from start-ups
Search for exotic bound states and measurement of the (anti-)alpha production yield in PbâPb collisions with ALICE at the LHC (CERN)
The ALICE detector system has excellent particle identification (PID) capabilities employing a variety of techniques. One of these is the specific energy loss dE/dx measurement in the Time Projection Chamber (TPC). The dE/dx is different for each particle species and can be used to identify charged particles including also (anti-)nuclei. The time-of-flight method uses the m^2/z^2 distributions (m = mass of the particle, z charge number of the particle), which are determined from the flight time and the length of the particle trajectory measured with the Time-Of-Flight (TOF) detector, and the momentum extracted through combined tracking in the ALICE setup in the mid-rapidity region.
Within this doctoral thesis these techniques are used for the search for two exotic bound states, the anti-În bound state and the H-dibaryon, as well as for the measurement of the production yield per unit of rapidity dN/dy of alpha and anti-alpha particles. Both, the searches for the exotica and the measurement of the (anti-)alpha, are performed on data from PbâPb collisions at sqrt(s_(NN)) = 2.76 TeV.
The searches for the two investigated exotica are carried out in the decay channel anti-În â anti-d + Ï+ and H â Î+p+Ïâ. The different decay products are identified using the specific energy loss measurements in the TPC and their invariant mass is determined. For both investigated bound states no signals are observed in the resulting invariant mass distributions. Therefore, upper limits on the production rates are estimated for eight different assumed lifetimes between 4 cm and 3 m. In addition, the upper limits are determined independent of the branching ratio of the investigated decay channel and are compared to different theory predictions.
The alpha particle is the heaviest nucleus produced and detected during ultra-relativistic heavy-ion collisions at LHC energies and the anti-alpha is even the heaviest anti-nucleus observed so far at all. The particles are identified using the dE/dx measurement in the TPC and the m^2/z^2 distributions determined with the measurements of the TOF. The efficiency Ă acceptance is determined using a Monte Carlo production. As the observed statistics does not allow for the determination of the transverse momentum pT-spectrum, a Blast-Wave extrapolation is used, which is based on the measurements of the spectra of deuterons and 3He. This allows for the pT-integrated determination of the efficiency. Systematic uncertainties are calculated and the resulting rapidity density dN/dy is comparable with the prediction from a thermal model
Access to digital finance: equity crowdfunding across countries and platforms
Financing entrepreneurship spurs innovation and economic growth. Digital financial platforms that crowdfund equity for entrepreneurs have emerged globally, yet they remain poorly understood. We model equity crowdfunding in terms of the relationship between the number of investors and the amount of money raised per pitch. We examine heterogeneity in the average amount raised per pitch that is associated with differences across three countries and seven platforms. Using a novel dataset of successful fundraising on the most prominent platforms in the UK, Germany, and the USA, we find the underlying relationship between the number of investors and the amount of money raised for entrepreneurs is loglinear, with a coefficient less than one and concave to the origin. We identify significant variation in the average amount invested in each pitch across countries and platforms. Our findings have implications for market actors as well as regulators who set competitive frameworks
Probing the evolution of heavy-ion collisions using direct photon interferometry
We investigate the measurement of Hanbury Brown-Twiss (HBT) photon
correlations as an experimental tool to discriminate different sources of
photon enhancement, which are proposed to simultaneously reproduce the direct
photon yield and the azimuthal anisotropy measured in nuclear collisions at
RHIC and the LHC. To showcase this, we consider two different scenarios in
which we enhance the yields from standard hydrodynamical simulations. In the
first, additional photons are produced from the early pre-equilibrium stage
computed from the \textit{bottom-up} thermalization scenario. In the second,
the thermal rates are enhanced close to the pseudo-critical temperature
using a phenomenological ansatz. We compute the
correlators for relative momenta and for different
transverse pair momenta, , and find that the longitudinal correlation
is the most sensitive to different photon sources. Our results also demonstrate
that including anisotropic pre-equilibrium rates enhances non-Gaussianities in
the correlators, which can be quantified using the kurtosis of the correlators.
Finally, we study the feasibility of measuring a direct photon HBT signal in
the upcoming high-luminosity LHC runs. Considering only statistical
uncertainties, we find that with the projected heavy ion events
a measurement of the HBT correlations for is
statistically significant
Characterization of a new Teflon chamber and on-line analysis of isomeric multifunctional photooxidation products
The photooxidation of volatile organic compounds (VOCs) in the troposphere has important implications for air quality, weather, and climate. A deeper understanding of the underlying mechanisms can be achieved by studying these reactions under controlled conditions and analysing the emerging photooxidation products. This requires dedicated laboratory infrastructure as well as sensitive and selective analytical techniques. Here, we constructed a new 300âL indoor Teflon atmospheric simulation chamber as part of the Bayreuth ATmospheric simulation CHambers (BATCH) infrastructure. The chamber was irradiated by a bandpass-filtered solar simulator that enabled experiments with realistic photon fluxes and OH radical concentrations. It was coupled to a proton-transfer-reaction time-of-flight mass spectrometer (PTR-ToF-MS) and a solid-phase microextractionâgas chromatographyâmass spectrometry (SPME-GC-MS) system for the on-line analysis of the precursor VOC and its oxidation products in the gas phase. As part of the SPME-GC-MS method, multifunctional oxygenated compounds (carbonyls, alcohols, carboxylic acids) were derivatized with O-(2,3,4,5,6-pentafluorobenzyl)hydroxylamine (PFBHA) and N-trimethylsilyl-N-methyltrifluoroacetamide (MSTFA). We designed a permeation source for the on-line addition of internal standards to improve method reproducibility. The joint setup was tested and validated by studying the OH-radical-induced photooxidation of toluene, one of the most abundant aromatic hydrocarbons in the atmosphere. For chamber characterization, we first derived the photolysis rates for several typical toluene products in the irradiated BATCH Teflon chamber (1.77âĂâ10â8â3.02âĂâ10â4âsâ1). Additionally, wall loss rates were determined empirically (4.54âĂâ10â6â8.53âĂâ10â5âsâ1) and then parameterized according to fundamental molecular properties. For the cresols, we compiled a weighted calibration factor for the PTR-ToF-MS, taking into account isomer-specific sensitivities as well as the relative distribution as determined by the SPME-GC-MS. The weighted calibration improved the instrumental agreement to 14â%, whereas the PTR-ToF-MS overestimated the sum of the isomers by 31â% compared to the SPME-GC-MS concentrations when using the averaged calibration factor. Thus, the combined data set offered insight into both temporal trends and the isomeric composition. Finally, we conducted six toluene photooxidation experiments to evaluate the ring-retaining first-generation products. Based on the loss-corrected concentrations, we derived formation yields for o-cresol (8.0â±â1.8â%), m-cresol (0.4â±â0.1â%), p-cresol (2.4â±â0.6â%), benzyl alcohol (0.5â±â0.1â%), and benzaldehyde (4.6â±â1.7â%) under NOx-free conditions at Tâ=â298â±â1âK. These yields are consistent with previous studies and therefore serve as proof of concept for our applied methods.</p
High count rate {\gamma}-ray spectroscopy with LaBr3:Ce scintillation detectors
The applicability of LaBr3:Ce detectors for high count rate {\gamma}-ray
spectroscopy is investigated. A 3"x3" LaBr3:Ce detector is used in a test setup
with radioactive sources to study the dependence of energy resolution and photo
peak efficiency on the overall count rate in the detector. Digitized traces
were recorded using a 500 MHz FADC and analysed with digital signal processing
methods. In addition to standard techniques a pile-up correction method is
applied to the data in order to further improve the high-rate capabilities and
to reduce the losses in efficiency due to signal pile-up. It is shown, that
{\gamma}-ray spectroscopy can be performed with high resolution at count rates
even above 1 MHz and that the performance can be enhanced in the region between
500 kHz and 10 MHz by using pile-up correction techniques
Embedding and assembly of ultrathin chips in multilayer flex boards
Dieser Beitrag ist mit Zustimmung des Rechteinhabers aufgrund einer (DFG geförderten) Allianz- bzw. Nationallizenz frei zugĂ€nglich.This publication is with permission of the rights owner freely accessible due to an Alliance licence and a national licence (funded by the DFG, German Research Foundation) respectively.Purpose â The purpose of this paper is to present results from the EC funded project SHIFT (Smart High Integration Flex Technologies) on the embedding in and the assembly on flex substrates of ultrathin chips.
Design/methodology/approach â Methods to embed chips in flex include flip-chip assembly and subsequent lamination, or the construction of a separate ultra-thin chip package (UTCP) using spin-on polyimides and thin-film metallisation technology. Thinning and separation of the chips is done using a âdicing-by-thinningâ method.
Findings â The feasibility of both chip embedding methods has been demonstrated, as well as that of the chip thinning method. Lamination of four layers of flex with ultrathin chips could be achieved without chip breakage. The UTCP technology results in a 60 mm package where also the 20mm thick chip is bendable.
Research limitations/implications â Further development work includes reliability testing, embedding of the UTCP in conventional flex, and construction of functional demonstrators using the developed technologies.
Originality/value â Thinning down silicon chips to thicknesses of 25mm and lower is an innovative technology, as well as assembly and embedding of these chips in flexible substrates.EC/FP6/EU/507745/Smart high-integration flex technologies/SHIF
The decay of quadrupole-octupole states in Ca and Ce
Background: Two-phonon excitations originating from the coupling of two
collective one-phonon states are of great interest in nuclear structure
physics. One possibility to generate low-lying excitations is the coupling
of quadrupole and octupole phonons.
Purpose: In this work, the -decay behavior of candidates for the
state in the doubly-magic nucleus Ca and in
the heavier and semi-magic nucleus Ce is investigated.
Methods: experiments have been carried out at the
High Intensity -ray Source (HIS) facility in combination with
the high-efficiency -ray spectroscopy setup consisting of
HPGe and LaBr detectors. The setup enables the acquisition of
- coincidence data and, hence, the detection of direct decay
paths.
Results: In addition to the known ground-state decays, for Ca the
decay into the state was observed, while for Ce the direct
decays into the and the state were detected. The experimentally
deduced transition strengths and excitation energies are compared to
theoretical calculations in the framework of EDF theory plus QPM approach and
systematically analyzed for isotones. In addition, negative parities for
two states in Ca were deduced simultaneously.
Conclusions: The experimental findings together with the theoretical
calculations support the two-phonon character of the excitation in the
light-to-medium-mass nucleus Ca as well as in the stable even-even
nuclei.Comment: 11 pages, 6 figures, as accepted in Phys. Rev.
Fragmentation and systematics of the Pygmy Dipole Resonance in the stable N=82 isotones
The low-lying electric dipole (E1) strength in the semi-magic nucleus 136Xe
has been measured which finalizes the systematic survey to investigate the
so-called pygmy dipole resonance (PDR) in all stable even N=82 isotones with
the method of nuclear resonance fluorescence using real photons in the entrance
channel. In all cases, a fragmented resonance-like structure of E1 strength is
observed in the energy region 5 MeV to 8 MeV. An analysis of the fragmentation
of the strength reveals that the degree of fragmentation decreases towards the
proton-deficient isotones while the total integrated strength increases
indicating a dependence of the total strength on the neutron-to-proton ratio.
The experimental results are compared to microscopic calculations within the
quasi-particle phonon model (QPM). The calculation includes complex
configurations of up to three phonons and is able to reproduce also the
fragmentation of the E1 strength which allows to draw conclusions on the
damping of the PDR. Calculations and experimental data are in good agreement in
the degree of fragmentation and also in the integrated strength if the
sensitivity limit of the experiments is taken into account
Design of a Low-Capacitance Planar Transformer for a 4 kW/500 kHz DAB Converter
International audienceIncreasing electrification in transport sectors, from automotive to aerospace, highlights the need for low size and high power density components. The recent advent of planar technology theoretically allows to reduce considerably the size of the magnetic components. This article focuses on the design of a high frequency planar transformer intended to be used in a 4 kW 500 kHz DAB converter. In particular, the inter-winding capacitances are assessed, as they have a strong influence on the behaviour of the DAB, and in some extreme cases may impede operation entirely. Analytical and finite element models are used to evaluate the stray elements of the transformer (resistance of the conductors, inter-winding capacitance and leakage inductance), and the resulting circuit model is compared with experimental measurements. This work focuses on influences of design parameters on the transformer stray elements
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