A Numerical Examination of the Performance of Small Magnetic Nozzle Thrusters

Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/143040/1/6.2017-4721.pd

Structural heterogeneity and pressure-relaxation in compressed borosilicate glasses by in situ small angle X-ray scattering

We report on Brillouin and in situ small angle X-ray scattering (SAXS) analyses of topological heterogeneity in compressed sodium borosilicate glasses. SAXS intensity extrapolated to very low angular regimes, I(q = 0), is related to compressibility. From Brillouin scattering and analyses of the elastic properties of the glass, the Landau-Placzek ratio is determined and taken as a direct reflection of the amplitude of frozen-in density fluctuations. It is demonstrated that with increasing fictive pressure, topological (mid- and long-range) homogeneity of the glass increases significantly. Heating and cooling as well as isothermal scans were performed to follow the evolution of density fluctuations upon pressure recovery. For a sample with a fictive pressure pf of 470 MPa, complete recovery to pf = 0.1 MPa was observed to occur close to the glass transition temperature. The values of fictive and apparent fictive temperature, respectively, as obtained via the intersection method from plots of I(q = 0) vs. temperature were found in good agreement with previous calorimetric analyses. Isothermal scans suggest that mid- and long-range recovery govern macroscopic density relaxation

Competitor See, Competitor Do: Incumbent Entry in New Market Niches

The ability to keep up with changing technology is critical for a company's long-term survival. However, companies have to balance the risk of rushing into new areas and potentially cannibalizing their existing business against the risk of missing the emerging market. This paper investigates when incumbents enter into new market niches created by technological innovation. We argue that market conditions and company-specific characteristics do not suffice to explain incumbents' entry timing, but that entry is a contagious process. Our results demonstrate that incumbents are more likely to respond to innovations in their industry when their counterparts do so. In particular, we show that incumbents are affected by the entry of firms that are similar in size and resources. When a highly similar company enters the new market, it raises the probability that the company enters itself beyond levels based solely on the attractiveness of the market.market entry, competition, new product research