Fe-doped amorphous FexCl~ granular films were prepared on n-Si （100） substrates by d.c. magnetron sputtering. The structur- al properties of FexC1-x films were investigated by X-ray diffraction （XRD）, atomic force...Fe-doped amorphous FexCl~ granular films were prepared on n-Si （100） substrates by d.c. magnetron sputtering. The structur- al properties of FexC1-x films were investigated by X-ray diffraction （XRD）, atomic force microscope （AFM） and Raman spec- troscopy. The results show that the iron and carbon of as-deposited films are in amorphous state, and the FexC1-x films are di- amond-like carbon （DLC） films. After doping iron into the DLC films, a smooth surface morphology of the FexC1-x films has been obtained with the surface roughness Ra of about 0.231 nm for x=18at%. The FexC1-x films have good soft magnetic prop- erties with the coercivity of approximately 20 Oe. A high positive magnetoresistance （MR） up to 93% with x=lat% was ob- served in a FexCl-x granular film at 300 K. The resistance characteristic of Fe-C films is changed at about 230 K and the positive MR effect can be understood by the p-n heterojunction theory.展开更多
We propose a robust watermarking scheme and several extensions for digital right management of data cubes.The ownership information is hidden into a data cube by modifying a set of selected cell values.Its owner can u...We propose a robust watermarking scheme and several extensions for digital right management of data cubes.The ownership information is hidden into a data cube by modifying a set of selected cell values.Its owner can use his private key to control all the watermarking parameters freely.Neither original data cube nor the watermark is required in watermark detection.Detailed analysis and extensive experiments are conducted for the proposed schemes in terms of watermark detectability,robustness and efficiency.Our results show that the scheme performs well in actual applications.展开更多
基金supported by the National Natural Science Foundation of China (Grant No. U0734001)the Fundamental Research Funds for the Central Universities,SCUT (Grant Nos. 2009ZM0247 and 2012ZZ0015)
文摘Fe-doped amorphous FexCl~ granular films were prepared on n-Si （100） substrates by d.c. magnetron sputtering. The structur- al properties of FexC1-x films were investigated by X-ray diffraction （XRD）, atomic force microscope （AFM） and Raman spec- troscopy. The results show that the iron and carbon of as-deposited films are in amorphous state, and the FexC1-x films are di- amond-like carbon （DLC） films. After doping iron into the DLC films, a smooth surface morphology of the FexC1-x films has been obtained with the surface roughness Ra of about 0.231 nm for x=18at%. The FexC1-x films have good soft magnetic prop- erties with the coercivity of approximately 20 Oe. A high positive magnetoresistance （MR） up to 93% with x=lat% was ob- served in a FexCl-x granular film at 300 K. The resistance characteristic of Fe-C films is changed at about 230 K and the positive MR effect can be understood by the p-n heterojunction theory.
基金the National Natural Science Foundation of China(No.60703032)the National High Technology Research and Development Program(863)of China(No.2007AA01Z456)
文摘We propose a robust watermarking scheme and several extensions for digital right management of data cubes.The ownership information is hidden into a data cube by modifying a set of selected cell values.Its owner can use his private key to control all the watermarking parameters freely.Neither original data cube nor the watermark is required in watermark detection.Detailed analysis and extensive experiments are conducted for the proposed schemes in terms of watermark detectability,robustness and efficiency.Our results show that the scheme performs well in actual applications.
