To improve polishing quality and cope with the shortage of skilled workers for aluminum wheel-hub surface polishing, an automatic surface polishing system with hierarchical control based on the teaching-playback metho...To improve polishing quality and cope with the shortage of skilled workers for aluminum wheel-hub surface polishing, an automatic surface polishing system with hierarchical control based on the teaching-playback method was presented. Multi-axis cutter location data (CL data) were generated with the teaching method. First, a helical tool path and a flexible polishing tool were adopted to achieve high quality and high efficiency; next, the initial irregular data were processed into continuous polishing CL data. The important factor affecting polishing quality, namely the interpolation cycle in the multi-axis CL data was calculated based on a constant removal rate. Results from polishing experiments show that the quality of automatic machine polishing is better and stabler than manual polishing.展开更多
This study was to understand the physiological changes of four kinds of crop seeds including baby corn, cowpea, radish and rape- seed, under the treatment of ultra-drying. Large amounts of seeds as experimental materi...This study was to understand the physiological changes of four kinds of crop seeds including baby corn, cowpea, radish and rape- seed, under the treatment of ultra-drying. Large amounts of seeds as experimental materials （ 10 kg for each material） were respectively dried to the suitable water content consistent with the ultra-dried seed criterion via heating at 50 ~C; then the physiological indices of these ultra-dried seeds such as water content, seed germination, dehydrogenase activity and SOD activity were measured. The results showed that except cowpea seeds, whose ultra-drying treatment should be controlled between two and four days, other three kinds of seeds were tolerant to high tem- perature and low water content. The ultra-dried seeds assumed similar or even higher activities than CKs, but showed no damage symptom. Our result proves that ultra-drying treatment via heating at 50 ℃ is safe and efficient to experimental seeds.展开更多
We study the global umbilic submanifolds with parallel mean curvature vector fields in a Riemannian manifold with quasi constant curvature and get a local pinching theorem about the length of the second fundamental form.
For the first time we investigate the basal thermal condition in the upper area of Jima Yangzong Glacier, the headstream of Yarlung Zangbo River, using ground-penetrating radar techniques. With common offset and commo...For the first time we investigate the basal thermal condition in the upper area of Jima Yangzong Glacier, the headstream of Yarlung Zangbo River, using ground-penetrating radar techniques. With common offset and common mid-point surveys we analyze the radar velocities in ice with respect to cold-temperate ice transi- tion surface （0.1751 0.0028 m ns-~） and ice-bedrock interface （0.1657 ＋ 0.0033 m ns-a）, indicating a radar velocity of 0.1410 4- 0.0154 m ns-1 for the temperate ice layer （16.6 ~ 1.8 m）. We estimate that the temperate ice layer has a water content of around 6 % 4- 4 %, suggesting that the Jima Yangzong Glacier, previously known as continental-type, now possibly becomes polythermal.展开更多
基金Funded by the Science and Technology Department of Zhejiang Province,China (No. 2005D60SA700351)
文摘To improve polishing quality and cope with the shortage of skilled workers for aluminum wheel-hub surface polishing, an automatic surface polishing system with hierarchical control based on the teaching-playback method was presented. Multi-axis cutter location data (CL data) were generated with the teaching method. First, a helical tool path and a flexible polishing tool were adopted to achieve high quality and high efficiency; next, the initial irregular data were processed into continuous polishing CL data. The important factor affecting polishing quality, namely the interpolation cycle in the multi-axis CL data was calculated based on a constant removal rate. Results from polishing experiments show that the quality of automatic machine polishing is better and stabler than manual polishing.
文摘This study was to understand the physiological changes of four kinds of crop seeds including baby corn, cowpea, radish and rape- seed, under the treatment of ultra-drying. Large amounts of seeds as experimental materials （ 10 kg for each material） were respectively dried to the suitable water content consistent with the ultra-dried seed criterion via heating at 50 ~C; then the physiological indices of these ultra-dried seeds such as water content, seed germination, dehydrogenase activity and SOD activity were measured. The results showed that except cowpea seeds, whose ultra-drying treatment should be controlled between two and four days, other three kinds of seeds were tolerant to high tem- perature and low water content. The ultra-dried seeds assumed similar or even higher activities than CKs, but showed no damage symptom. Our result proves that ultra-drying treatment via heating at 50 ℃ is safe and efficient to experimental seeds.
基金Supported by the Directing Research Subject of Jiangsu Education Bureau(03103146)
文摘We study the global umbilic submanifolds with parallel mean curvature vector fields in a Riemannian manifold with quasi constant curvature and get a local pinching theorem about the length of the second fundamental form.
基金supported by the Polar Atmospheric Science Field Base of CAMS(2016Z005)National Natural Science Foundation of China(41425003)National Fundamental Research Project(973)of China(2007CB411503)
文摘For the first time we investigate the basal thermal condition in the upper area of Jima Yangzong Glacier, the headstream of Yarlung Zangbo River, using ground-penetrating radar techniques. With common offset and common mid-point surveys we analyze the radar velocities in ice with respect to cold-temperate ice transi- tion surface （0.1751 0.0028 m ns-~） and ice-bedrock interface （0.1657 ＋ 0.0033 m ns-a）, indicating a radar velocity of 0.1410 4- 0.0154 m ns-1 for the temperate ice layer （16.6 ~ 1.8 m）. We estimate that the temperate ice layer has a water content of around 6 % 4- 4 %, suggesting that the Jima Yangzong Glacier, previously known as continental-type, now possibly becomes polythermal.
