The space charge behavior of a dielectric under HVDC is influenced by the charge trap energy distribution in it. Hence, we in- vestigated the charge trap distributions in several kinds of typical polymer materials usi...The space charge behavior of a dielectric under HVDC is influenced by the charge trap energy distribution in it. Hence, we in- vestigated the charge trap distributions in several kinds of typical polymer materials using thermally stimulated discharge (TSD) and photo-stimulated discharge (PSD) methods, respectively. The experimental results show that,there is a significant difference between the trap energy distributions obtained by the two methods, but the difference decreases with the increase of the melting point of polymers. This is attributed to the change of the trap center environment during TSD caused by the increasing movements of both main chains and branched chains in polymers. PSD method is more accurate for investigating charge trap distribution in dielectrics, especially for polymers with low melting points.展开更多
The international community has blamed developing countries for the lack of intellectual property rights(IPR)protection-not least the“forced technology transfers”-in attracting foreign direct investment(FDI).This pa...The international community has blamed developing countries for the lack of intellectual property rights(IPR)protection-not least the“forced technology transfers”-in attracting foreign direct investment(FDI).This paper employs the largesample contract data of multinational companies’(MNCs)IT R&D transactions in China to discuss this controversy from a unique perspective of MNCs in the role of contractors.Our findings suggest that MNCs initially guarded their know-how before the 2000s under closed innovation,but have started to take the initiative to transfer technology to local partners as open innovation held sway.China’s structured market entities and huge demand for technology transactions have served as key drivers for MNCs to transfer technology,which has been further boosted by the new business model of open innovation.This paper’s empirical analysis not only helps unravel the“black box”of technology transfers by MNCs,but reveals how late-moving developing countries may make better use of FDI referencing China’s experience on the three dimensions of market opportunities,structured entities,and economies of scale.展开更多
基金Project supported by National Natural Science Foundation of China (51077101, 51277133), National Basic Research Program of China (973 Program) (2009CB 724505).
文摘The space charge behavior of a dielectric under HVDC is influenced by the charge trap energy distribution in it. Hence, we in- vestigated the charge trap distributions in several kinds of typical polymer materials using thermally stimulated discharge (TSD) and photo-stimulated discharge (PSD) methods, respectively. The experimental results show that,there is a significant difference between the trap energy distributions obtained by the two methods, but the difference decreases with the increase of the melting point of polymers. This is attributed to the change of the trap center environment during TSD caused by the increasing movements of both main chains and branched chains in polymers. PSD method is more accurate for investigating charge trap distribution in dielectrics, especially for polymers with low melting points.
基金the Beijing Municipal Social Sciences Foundation Program “Study on Innovation Clusters, Governance RulesInnovation-Driven Development in the Capital City” (Grant No.20AJL007, 14JGB049)a special program from the Beijing Municipal TechnologyMarket Administration Office.
文摘The international community has blamed developing countries for the lack of intellectual property rights(IPR)protection-not least the“forced technology transfers”-in attracting foreign direct investment(FDI).This paper employs the largesample contract data of multinational companies’(MNCs)IT R&D transactions in China to discuss this controversy from a unique perspective of MNCs in the role of contractors.Our findings suggest that MNCs initially guarded their know-how before the 2000s under closed innovation,but have started to take the initiative to transfer technology to local partners as open innovation held sway.China’s structured market entities and huge demand for technology transactions have served as key drivers for MNCs to transfer technology,which has been further boosted by the new business model of open innovation.This paper’s empirical analysis not only helps unravel the“black box”of technology transfers by MNCs,but reveals how late-moving developing countries may make better use of FDI referencing China’s experience on the three dimensions of market opportunities,structured entities,and economies of scale.