trast （HC） method is proposed to define saliency value of each pixel, then auto Grabcut segmenta- tion method is used to segment the salient region so as to obtain a region of interest （ROI）. After that, normalize...trast （HC） method is proposed to define saliency value of each pixel, then auto Grabcut segmenta- tion method is used to segment the salient region so as to obtain a region of interest （ROI）. After that, normalized histograms and cumulative histograms for ROI and region of background （ROB） are calculated. The mapping functions of the corresponding regions are derived from reference image to distorted image through the nearest cumulative histogram matching method, so that color correction can be finally achieved. Experimental results show that benefitting from the separate treatment to ROI and ROB, the proposed color correction method could avoid error propagation between the two different regions, which achieves good color correction result in comparison with other correction methods.展开更多
Growth process of iron whiskers and mechanism of CaO influence on precipitation morphology of metallic iron at the gas-solid interfaces was studied. Analytical reagents of Fe（NO3）3 and Ca（NO3）2 aqueous solution we...Growth process of iron whiskers and mechanism of CaO influence on precipitation morphology of metallic iron at the gas-solid interfaces was studied. Analytical reagents of Fe（NO3）3 and Ca（NO3）2 aqueous solution were used to prepare sheet film sample of Fe2 O3-CAO by thermal decomposition at high temperature. In-situ observation was con-ducted using a stereo optical microscope and a hot-stage. And reduction kinetics of samples was studied by thermo gravimetrie （TG） method. Some samples after reduction were analyzed by using the scanning electron microscope （SEM）, energy dispersive spectrometer （EDS） and fourier transform infrared （FT-IR） spectrometer. Results indi-cate that during the reduction of iron oxides with CO, metallic iron is mostly precipitated as whisker and the precipi- tation behavior mainly depends on reduction rate. Doping CaO can significantly increase the reduction rate and effec-tively change the precipitation morphology of metallic iron after the reduction. When CaO doping concentration is less than 4% （mass percent）, CaO can promote whisker formation of reduced iron; as it reaches 6% （mass per- cent）, CaO inhibits iron whiskers growth; as it is more than 8% （mass percent）, no whiskers could be observed. Therefore, controlling the quantity of Ca^2＋ is effective to control the formation and growth of iron whiskers during gaseous reduction and thus eliminating ore grain sticking caused by intertexture of iron whiskers.展开更多
基金Supported by the Natural Science Foundation of China(No.61311140262,61171163,61271021)
文摘trast （HC） method is proposed to define saliency value of each pixel, then auto Grabcut segmenta- tion method is used to segment the salient region so as to obtain a region of interest （ROI）. After that, normalized histograms and cumulative histograms for ROI and region of background （ROB） are calculated. The mapping functions of the corresponding regions are derived from reference image to distorted image through the nearest cumulative histogram matching method, so that color correction can be finally achieved. Experimental results show that benefitting from the separate treatment to ROI and ROB, the proposed color correction method could avoid error propagation between the two different regions, which achieves good color correction result in comparison with other correction methods.
基金Item Sponsored by National Natural Science Foundation of China ( 50834007 )National Basic Research Program of China ( 2012CB720401 )
文摘Growth process of iron whiskers and mechanism of CaO influence on precipitation morphology of metallic iron at the gas-solid interfaces was studied. Analytical reagents of Fe（NO3）3 and Ca（NO3）2 aqueous solution were used to prepare sheet film sample of Fe2 O3-CAO by thermal decomposition at high temperature. In-situ observation was con-ducted using a stereo optical microscope and a hot-stage. And reduction kinetics of samples was studied by thermo gravimetrie （TG） method. Some samples after reduction were analyzed by using the scanning electron microscope （SEM）, energy dispersive spectrometer （EDS） and fourier transform infrared （FT-IR） spectrometer. Results indi-cate that during the reduction of iron oxides with CO, metallic iron is mostly precipitated as whisker and the precipi- tation behavior mainly depends on reduction rate. Doping CaO can significantly increase the reduction rate and effec-tively change the precipitation morphology of metallic iron after the reduction. When CaO doping concentration is less than 4% （mass percent）, CaO can promote whisker formation of reduced iron; as it reaches 6% （mass per- cent）, CaO inhibits iron whiskers growth; as it is more than 8% （mass percent）, no whiskers could be observed. Therefore, controlling the quantity of Ca^2＋ is effective to control the formation and growth of iron whiskers during gaseous reduction and thus eliminating ore grain sticking caused by intertexture of iron whiskers.
