218 research outputs found
Local knowledge spillovers and innovation persistence of firms
Recent empirical evidence has shown that firm’s innovation behavior exhibits high persistency but not much is known about potential contingencies affecting the degree of persistence. This paper focuses on the role of the local knowledge environment and asks how local knowledge spillovers affect firms' innovation persistence. The empirical analysis draws upon a representative panel data set of firms in Germany from 2002-2016, complemented by detailed geographic information of patent activity over discrete distances to proxy local knowledge spillovers. Based on correlated random effects probit models that control for state dependence, unobserved individual heterogeneity and endogenous initial conditions, our results corroborate former evidence that persistency in innovation is driven by true state dependence. More importantly, we find that the local patenting activity positively moderates firms' degree of persistency in innovation behavior. This is a novel firm-level mechanism that can explain the widening of spatial disparities in innovation performance. Estimations with different distance bands show that the strength of knowledge spillovers that contribute to innovation persistence via true state dependence declines rather rapidly with increasing distance
LEAN PANEL BENDER – Einige mechanische Aspekte der Modellierung in Echtzeit für Produktion in Losgröße 1
Nachfolgend werden einige wissenschaftliche Aspekte der Echtzeit-Materialerkennungsstrategie MAC diskutiert, die in der neuen Maschinenfamilie LEAN PANEL BENDER der Firma Salvagnini Maschinenbau realisiert ist und die eine hochpräzise und hocheffiziente Herstellung von komplex geformten Blechprodukten sowohl bei Losgröße 1 als auch in der Serie erlaubt.(VLID)342339
Industrial application of advanced adaptive concepts for automatic panel benders
Recently, the requirements on sheet metal production processes have increased significantly. Highest precision and flexibility with efficient energy consumption and short cycle times can be achieved by advanced concepts only. This requires a deep insight into the non-linear bending process. For this sake, efficient simulation models have been implemented to model the bending process: two and three dimensional finite element models combined with multibody simulation tools, contact mechanics algorithms and substructure techniques. The simulation tools have been successfully calibrated by measurement results. With the obtained detailed process knowledge, new adaptive concepts have been introduced, e.g. a smart crowning system in order to achieve straight profiles. The industrial application has shown the advantage of utilizing the above mentioned techniques. The straightness of the bends has been significantly increased, while energy consumption and cycle times have been reduced. Secondly, the development time of new machine concepts has been drastically reduced, such that the first prototype can be transferred to series production within short time. Moreover, the applied strategies show a large potential for future developments
Advanced mechanical simulation models for automatic panel benders
With automatic panel benders complete products are manufactured from sheet metal. In order to achieve short cycle times with high flexibility, a deep insight into the non-linear bending process is required. For this reason, efficient mechanical simulation models have been implemented, combining Finite Element Method, multibody dynamics simulation tools, contact mechanics algorithms and substructuring. Scope of this work is the comparison of several simulation models with measurement results performed on a Salvagnini P4XeD
automatic panel bender
Large tunable valley splitting in edge-free graphene quantum dots on boron nitride
Coherent manipulation of binary degrees of freedom is at the heart of modern
quantum technologies. Graphene offers two binary degrees: the electron spin and
the valley. Efficient spin control has been demonstrated in many solid state
systems, while exploitation of the valley has only recently been started, yet
without control on the single electron level. Here, we show that van-der Waals
stacking of graphene onto hexagonal boron nitride offers a natural platform for
valley control. We use a graphene quantum dot induced by the tip of a scanning
tunneling microscope and demonstrate valley splitting that is tunable from -5
to +10 meV (including valley inversion) by sub-10-nm displacements of the
quantum dot position. This boosts the range of controlled valley splitting by
about one order of magnitude. The tunable inversion of spin and valley states
should enable coherent superposition of these degrees of freedom as a first
step towards graphene-based qubits
Efficacy and Toxicity of Different Chemotherapy Protocols for Concurrent Chemoradiation in Non-Small Cell Lung Cancer—A Secondary Analysis of the PET Plan Trial
(1) Background: The optimal chemotherapy (CHT) regimen for concurrent chemoradiation
(cCRT) is not well defined. In this secondary analysis of the international randomized PET-Plan
trial, we evaluate the efficacy of different CHT. (2) Methods: Patients with inoperable NSCLC
were randomized at a 1:1 ratio regarding the target volume definition and received isotoxically
dose-escalated cCRT using cisplatin 80 mg/m2
(day 1, 22) and vinorelbin 15 mg/m2
(day 1, 8, 22, 29)
(P1) or cisplatin 20 mg/m2
(day 1–5, 29–33) and vinorelbin 12.5 mg/m2
(day 1, 8, 15, 29, 36, 43) (P2) or
carboplatin AUC1 (day 1–5, 29–33) and vinorelbin 12.5 mg/m2
(day 1, 8, 15, 29, 36, 43) (P3) or other
CHT at the treating physician’s discretion. (3) Results: Between 05/2009 and 11/2016, 205 patients
were randomized and 172 included in the per-protocol analysis. Patients treated in P1 or P2 had a
better overall survival (OS) compared to P3 (p = 0.015, p = 0.01, respectively). Patients treated with
carboplatin had a worse OS compared to cisplatin (HR 1.78, p = 0.03), but the difference did not
remain significant after adjusting for age, ECOG, cardiac function creatinine and completeness of
CHT. (4) Conclusions: Carboplatin doublets show no significant difference compared to cisplatin,
after adjusting for possibly relevant factors, probably due to existing selection bias
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