• Asia-pacific Journal of Multimedia Services Convergent with Art, Humanities, and Sociology
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• v.9 no.6
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• pp.711-718
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• 2019

Spectrum analyzer and electromagnetic field meter were used to investigate the EM generation behaviour in different types of home electrical appliances. During microwave oven operation, the EM power measured at a point 30cm apart was measured in the range of 8~11mW/㎡, the strength of the low frequency magnetic field was 60~80mG and the electric field strength was measured at 150~160V/m. For smart phone wireless charging pad, it was measured at an electromagnetic power of 0.4mW/㎡, an electric field of 160 V/m and a magnetic field of 1mG at a point 10cm away. For microwave oven and wireless charging pad, if used within 10cm, the size of the electric field has been measured at a large value that exceeds the human body protection standard and may be hazardous to humans. On the other hand, home appliances such as TVs, hairdryers and refrigerators all showed very low levels of electromagnetic waves, electric fields and magnetic fields, with no harmful effects seen. For electromagnetic shielding, the metal Cu fabric and metal foil had a high level of EM shielding, while polymer films had a low EM shielding characteristic.

• Korean Journal of Heritage: History & Science
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• v.47 no.3
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• pp.188-207
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• 2014

Taking the concept of 'Invention of Tradition' by Hobsbawm, this paper examines the change of perspectives on the past and the attitudes toward connecting the past and the contemporary in the 19th century restoration of religious buildings in England. The Anglican society in the early 19th century argued that the catholic theology and rituals should be revived in their practice, which has formed the Oxford Movement. Such aspiration has stimulated to the society to execute its religious practice in a proper space, which has resulted in the Cambridge Camden Society in the middle of the century. Their publications on church buildings and arrangement had much affected to the restoration of many churches to rip off the previous Georgian furnitures and features of the fabric into Gothic, the style of middle age. The perspective on the past for anti-restoration movement in the late 19th century has moved into the one to respect all historical layers of previous spirit imprinted in the church buildings. Inspired by Ruskin and formulated by Morris, SPAB's Manifesto has reflected that the spirit of the first builder can not be reproduced or copied by the contemporaries, and therefore a daily maintenance is the best practice to extend the life of spirit rather than restoration. In addition the material remains is no longer belong to the religious entity but should be regarded as national heritage. By examining the change of perspectives on the past between the early and middle of 19th century and the late 19th century, this paper has argued that the various factors such as social, economic, political, art and commercial factors should be examined together in the understanding of conservation history.