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Financial theory creates a puzzle. Some authors argue that high-risk entrepreneurs choose debt contracts instead of equity contracts since risky but high returns are of relatively more value for a loan-financed firm. Conversely, authors who focus explicitly on start-up finance predict that entrepreneurs are the more likely to seek equity-like venture capital contracts, the more risky their projects are. Our paper is an initial step towards resolving this puzzle empirically. We present microeconometric evidence on the determinants of debt and equity financing in young and innovative SMEs. We pay special attention to the role of risk for the choice of the method of financing. Since risk is not directly observable we use different indicators for financial and project risk. It turns out that our data generally confirms the hypothesis that the probability that a young high-tech firm receives equity financing is an increasing function of the financial risk. With regard to the intrinsic project risk, our results are less conclusive, as some of our indicators of a risky project are found to have a negative effect on the likelihood to be financed by private equity.  相似文献   
3.
Bayesian analysis is used to show that Wald's sequential probability ratio test with varying thresholds is optimal for the nonstationary situation, where the observed samples are independent but not identically distributed. Some important properties useful for the design of the test thresholds are discussed. Wald's lower bound, generalized to the nonstationary situation, is also presented. The results have important applications in situations where the observed signal is time-varying. such as in radar signal processing, image processing, and spread spectrum communications  相似文献   
4.
Multiple antenna systems: their role and impact in future wireless access   总被引:2,自引:0,他引:2  
Multiple antennas play an important role in improving radio communications. In view of this role, the area of multiple antenna communication systems is in the forefront of wireless research. This article reviews two key related aspects of multiple antenna communication systems: multiple access interference mitigation at the receiver via multi-user beamforming; and space-time modulation and coding for MIMO systems. It is shown that both multi-user and MIMO receivers share similar signal processing and complexity tradeoffs.. Following that, a general unified framework for assessing different types of space-time modulation for MIMO systems is introduced. These space-time modulation methods are then compared in terms of Shannon capacity over multipath channels. Key MIMO system performance and implementation issues are also highlighted.  相似文献   
5.
Determination of Pentane as an Indicator of Oil Rancidity Pentane, determined by a headspace gas chromatographic method, is an excellent indicator of oil rancidity. The methodology applied is very simple and could be performed in an oil laboratory without purchasing additional equipment. The amount of pentane correlated well with the iodometrically determined peroxide value (R2-value of 0.976). Heating the oil sample in air followed by an estimation of pentane is an alternative means to assess oil stability against oxidative deterioration.  相似文献   
6.
Properties of a single-chain antibody containing different linker peptides   总被引:1,自引:0,他引:1  
Single-chain antibodies were constructed using six differentlinker peptides to join the VH and VL domains of an anti-2-phenyloxazolone(Ox) antibody. Four of the linker peptides originated from theinterdomain linker region of the fungal cellulase CBHI and consistedof 28, 11, six and two amino acid residues. The two other linkerpeptides used were the (GGGGS)3 linker with 15 amino acid residuesand a modified IgG2b hinge peptide with 22 residues. Proteolyticstability and Ox binding properties of the six different scFvderivatives produced in Escherichia coli were investigated andcompared with those of the corresponding Fv fragment containingno joining peptide between the V domains. The hapten bindingproperties of different antibody fragments were studied by ELISAand BIAcoreTM. The interdomain linker peptide improved the haptenbinding properties of the antibody fragment when compared withFv fragment, but slightly increased its susceptibility to proteases.Single-chain antibodies with short CBHI linkers of 11, six andtwo residues had a tendency to form multimers which led to ahigher apparent affinity. The fragments with linkers longerthan 11 residues remained monomeric.  相似文献   
7.
Superhydrophobic coatings are widely applicable, e.g., as self-cleaning surfaces or water–oil separation membranes, yet their wider usage is impeded due to costs of fabrication, size, or substrate limitation. Spray-coating is a versatile coating procedures and might offer a good solution for the fabrication of these superhydrophobic coatings, due to the fact that coatings can be fabricated on various materials in a simple, fast, and inexpensive manner. Most procedures rely on hybrid coatings of hydrophobized nanoparticles and a polymeric matrix, which have several drawbacks including the easy loss of nanoparticles and difficult waste handling. Here, the fabrication of the superhydrophobic material, called Fluoropor, for the first time, by spray-coating on various substrates including metals, tissues, concrete, and glass is presented. It is fabricated by spray-coating a mixture of a highly fluorinated monomer blended with porogens followed by photopolymerization. The superhydrophobicity of the material relies on the porous structure on the micro-/nanoscale across the bulk material and does not require any nanoparticles. Excellent self-cleaning ability of these coatings, resistance against thermal and abrasive impact, and their application as oil–water separation membranes are shown. This versatile applicability is highly promising for real-world application as self-cleaning coatings or oil–water separating membranes.  相似文献   
8.
Beierlein  Dennis  Häussermann  Dorothea  Traa  Yvonne  Klemm  Elias 《Catalysis Letters》2022,152(10):2908-2919
Catalysis Letters - We developed a rapid aging method for Ni/Al2O3 methanation catalysts mimicking the real aging in the actual application. The method is based on hydrothermal deactivation of the...  相似文献   
9.
The total neutron cross sections of mesitylene, toluene and a solution 3:2 by volume of mesitylene and toluene were measured at the electron LINAC based pulsed neutron source of Centro Atómico Bariloche. Measurements were performed at 180 K, 120 K and 31.6 K for mesitylene and at 120 K and 31.6 K for toluene and a solution 3:2 by volume of mesitylene and toluene. The systems are potential moderator materials to be considered in the design of a cold neutron source due to their high resistance to radiation and the richness in low-energy excitations of their frequency spectra, that lead to produce an enhanced cold neutron flux.  相似文献   
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