An entropy-based indicator system for measuring the potential of patents in technological innovation: rejecting moderation

© 2017, Akadémiai Kiadó, Budapest, Hungary. How to evaluate the value of a patent in technological innovation quantitatively and systematically challenges bibliometrics. Traditional indicator systems and weighting approaches mostly lead to “moderation” results; that is, patents ranked to a top list can have only good-looking values on all indicators rather than distinctive performances in certain individual indicators. Orienting patents authorized by the United States Patent and Trademark Office (USPTO), this paper constructs an entropy-based indicator system to measure their potential in technological innovation. Shannon’s entropy is introduced to quantitatively weight indicators and a collaborative filtering technique is used to iteratively remove negative patents. What remains is a small set of positive patents with potential in technological innovation as the output. A case study with 28,509 USPTO-authorized patents with Chinese assignees, covering the period from 1976 to 2014, demonstrates the feasibility and reliability of this method

Insulator-metal transition shift related to magnetic polarons in La0.67-xYxCa0.33MnO3

The magnetic transport properties have been measured for La0.67-xYxCa0.33MnO3 (0 <= x <= 0.14) system. It was found that the transition temperature Tp almost linearly moves to higher temperature as H increases. Electron spin resonance confirms that above Tp, there exist ferromagnetic clusters. From the magnetic polaron point of view, the shift of Tp vs. H was understood, and it was estimated that the size of the magnetic polaron is of 9.7~15.4 angstrom which is consistent with the magnetic correlation length revealed by the small-angle neutron-scattering technique. The transport properties at temperatures higher than Tp conform to the variable-range hopping mechanism.Comment: 22 pages, 6 figures, pdf, to be published in Euro. Phys. J.

Optimization of Tertiary Alkaloids Separation from Corydalis yanhusuo by Macroporous Resins

Corydalis yanhusuo is used widely for the treatment of gastralgia, costalgia and dysmenorrhea in Chinese medicine. The alkaloid is the main active ingredient of C. yanhusuo. Response surface methodology was applied to optimize the separation and purification process for alkaloids by AB-8 resin-packed chromatogram column. The optimal conditions were found to be as follows: height-diameter ratio of AB-8 resin-packed chromatogram column, 10.50; concentration and pH of feed sample solution, 1.12 mg mL–1 and 7.16, respectively. The gradient elution program was 30 % ethanol for 2 BV (bed volume) followed by 80 % of ethanol for 5 BV at flow rate of 3 mL min–1. After the AB-8 resin treatment, the contents of alkaloids and tetrahydropalmatine were increased respectively from 25.20 % and 2.12 % to 58.25 % and 6.58 %, the recovery of alkaloids and tetrahydropalmatine were 85.40 % and 65.21 %, respectively. The results indicated that the optimization of alkaloid separation from C. yanhusuo by macroporous resins is feasible and efficient

A hybrid method to trace technology evolution pathways: a case study of 3D printing

© 2017, Akadémiai Kiadó, Budapest, Hungary. Whether it be for countries to improve the ability to undertake independent innovation or for enterprises to enhance their international competitiveness, tracing historical progression and forecasting future trends of technology evolution is essential for formulating technology strategies and policies. In this paper, we apply co-classification analysis to reveal the technical evolution process of a certain technical field, use co-word analysis to extract implicit or unknown patterns and topics, and employ main path analysis to discover significant clues about technology hotspots and development prospects. We illustrate this hybrid approach with 3D printing, referring to various technologies and processes used to synthesize a three-dimensional object. Results show how our method offers technical insights and traces technology evolution pathways, and then helps decision-makers guide technology development

Ab initio calculation of intrinsic spin Hall effect in semiconductors

Relativistic band theoretical calculations reveal that intrinsic spin Hall conductivity in hole-doped archetypical semiconductors Ge, GaAs and AlAs is large $[\sim 100 (\hbar/e)(\Omega cm)^{-1}]$, showing the possibility of spin Hall effect beyond the four band Luttinger Hamiltonian. The calculated orbital-angular-momentum (orbital) Hall conductivity is one order of magnitude smaller, indicating no cancellation between the spin and orbital Hall effects in bulk semiconductors. Furthermore, it is found that the spin Hall effect can be strongly manipulated by strains, and that the $ac$ spin Hall conductivity in the semiconductors is large in pure as well as doped semiconductors.Comment: Phys. Rev. Lett. (accepted