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In this study, we developed an energy security evaluation model (ESEM) from three dimensions, energy supply-transport security, safety of energy utilization, and stability of political-socioeconomic environment, based on the integrated application of subjective and objective weight allocation technique. Then the spatial-temporal evolution of global energy security pattern and its driving mechanism was analyzed with the method above, and the results are shown as follows: (1) since the 1990s, the spatial patterns of global energy security have shown a deteriorating trend, with the growth of countries in at-risk type and relatively at-risk type. (2) The spatial distribution of countries with secure energy system shows a strong stability, and these countries are concentrated persistently in Western Europe and North America. The spatial evolution of countries with relatively secure energy system also presents a strong stability, which are mainly distributed in the periphery of the secure ones, namely Central and Southern Europe, South America and Eurasia, while countries with general energy system are mainly distributed in Asia, Africa and Southern Europe, and the spatial-temporal evolution of this type is the main cause for the deterioration of world energy security pattern. Countries with at-risk and relatively at-risk energy system are mainly concentrated in Africa, Asia, the Middle East and Eurasia, rendering spatial extension to the east and south. (3) In the past 20 years, the mechanism for world's energy security pattern formation gradually transforms from the 'unitary dimension dominated' to the 'binary dimension-dominated', and the main factors influencing the global energy security pattern become more diverse. (4) In the pattern of world's energy security, China's performance on energy security has been the global average since the 1990s, which shows a decreasing trend in safety of energy utilization dimension. Findings in this study can provide a reference for the government in terms of formulating strategic responses and policy options.

We have developed a very sensitive transmission line-type thin film sensor. The sensor, consisting of a coplanar line, SiO ２ film, and amorphous CoFeSiB film, was fabricated by sputtering, lift-off, and lithography processes. A phase change of 45 degrees/Oe was obtained at 1 GHz. We arranged two-dimensional stepping motors and developed a scanning system for the sensor. Aluminum samples with through holes were examined by using the eddy current method. Aluminum wires with small Fe balls as impurities were tested by measuring the DC field.

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