使用前苏联Valdai 1966～1971年的气象观测资料，研究了通用陆面模式（Common Land Model，CoLM）模拟的水分循环和地表通量在12种土壤质地和8种土壤亮度条件下的差异。结果表明，在相同的气象条件下，模拟的热通量对土壤质地和亮度都...使用前苏联Valdai 1966～1971年的气象观测资料，研究了通用陆面模式（Common Land Model，CoLM）模拟的水分循环和地表通量在12种土壤质地和8种土壤亮度条件下的差异。结果表明，在相同的气象条件下，模拟的热通量对土壤质地和亮度都比较敏感，而地表水文过程只对土壤质地敏感。土壤亮度相同时，相对砂性土壤，粘土含量高的土壤保水性强，土壤湿度、地表蒸发和径流量都比较大（月均最大差值：土壤湿度约为5kg·m^-2，地表蒸发和径流量约为年降水量的7％和1．2％），相应地在热通量分配上存在明显差异（月均最大差值为8W·m^-2）；土壤质地相同，亮度由亮变暗时，潜热通量变化很小，地表温度略有升高，而感热通量和净辐射增加显著（月均摄大差值为7W·m^-2）。土壤质地和亮度对模拟的影响主要存在于降水少、植被覆盖度低的3～5月。展开更多
Objective To evaluate the optic nerve impairment using MRI histogram texture analysis in the patients with optic neuritis.Methods The study included 60 patients with optic neuritis and 20 normal controls. The coronal ...Objective To evaluate the optic nerve impairment using MRI histogram texture analysis in the patients with optic neuritis.Methods The study included 60 patients with optic neuritis and 20 normal controls. The coronal T2 weighted imaging(T2 WI) with fat saturation and enhanced T1 weighted imaging(T1 WI) were performed to evaluate the optic nerve. MRI histogram texture features of the involved optic nerve were measured on the corresponding coronal T2 WI images. The normal optic nerve(NON) was measured in the posterior 1/3 parts of the optic nerve. Kruskal-Wallis one-way ANOVA was used to compare the difference of texture features and receiver operating characteristic(ROC) curve were performed to evaluate the diagnostic value of texture features for the optic nerve impairment among the affected optic nerve with enhancement(ONwEN), affected optic nerve without enhancement(ONwoEN), contralateral normal appearing optic nerve(NAON) and NON. Results The histogram texture Energy and Entropy presented significant differences for ONwEN vs. ONwoEN(both P = 0.000), ONwEN vs. NON(both P = 0.000) and NAON vs. NON(both P < 0.05). ROC analysis demonstrated that the area under the curve(AUC) of histogram texture Energy were 0.758, 0.795 and 0.701 for ONwEN vs. ONwoEN, ONwEN vs. NON and NAON vs. NON, AUC of Entropy were 0.758, 0.795 and 0.707 for ONwEN vs. ONwoEN, ONwEN vs. NON and NAON vs. NON.Conclusion The altered MRI histogram texture Energy and Entropy could be considered as a surrogate for MRI enhancement to evaluate the involved optic nerve and normal-appearing optic nerve in optic neuritis.展开更多
The effects of different solution methods on microstructure, mechanical properties and precipitation behavior of Al-Mg-Si alloy were investigated by scanning electron microscope, transmission electron microscope, tens...The effects of different solution methods on microstructure, mechanical properties and precipitation behavior of Al-Mg-Si alloy were investigated by scanning electron microscope, transmission electron microscope, tensile test, and differential scanning calorimetry. The results revealed that the recrystallized grains of the alloy after the solution treatment with hot air became smaller and more uniform, compared with solution treatment with electrical resistance. The texture of the alloy after two solution treatment methods was different. More rotated cube components were formed through solution treatment with electrical resistance, which was better for improving the drawability of the alloy. The strength of the alloy under the solution treatment with hot air was higher before stamping, because of the small uniform grains and many clusters in the matrix. The alloy solution treated with hot air also possessed good bake hardenability, because the transformation occurred on more clusters in the matrix.展开更多
Texture optimization is a texture synthesis method that can efficiently reproduce various features of exemplar textures. However, its slow synthesis speed limits its usage in many interactive or real time applications...Texture optimization is a texture synthesis method that can efficiently reproduce various features of exemplar textures. However, its slow synthesis speed limits its usage in many interactive or real time applications. In this paper, we propose a parallel texture optimization algorithm to run on GPUs. In our algorithm, k-coherence search and principle component analysis （PCA） are used for hardware acceleration, and two acceleration techniques are further developed to speed up our GPU-based texture optimization. With a reasonable precomputation cost, the online synthesis speed of our algorithm is 4000＋ times faster than that of the original texture optimization algorithm and thus our algorithm is capable of interactive applications. The advantages of the new scheme are demonstrated by applying it to interactive editing of flow-guided synthesis.展开更多
文摘使用前苏联Valdai 1966～1971年的气象观测资料，研究了通用陆面模式（Common Land Model，CoLM）模拟的水分循环和地表通量在12种土壤质地和8种土壤亮度条件下的差异。结果表明，在相同的气象条件下，模拟的热通量对土壤质地和亮度都比较敏感，而地表水文过程只对土壤质地敏感。土壤亮度相同时，相对砂性土壤，粘土含量高的土壤保水性强，土壤湿度、地表蒸发和径流量都比较大（月均最大差值：土壤湿度约为5kg·m^-2，地表蒸发和径流量约为年降水量的7％和1．2％），相应地在热通量分配上存在明显差异（月均最大差值为8W·m^-2）；土壤质地相同，亮度由亮变暗时，潜热通量变化很小，地表温度略有升高，而感热通量和净辐射增加显著（月均摄大差值为7W·m^-2）。土壤质地和亮度对模拟的影响主要存在于降水少、植被覆盖度低的3～5月。
文摘Objective To evaluate the optic nerve impairment using MRI histogram texture analysis in the patients with optic neuritis.Methods The study included 60 patients with optic neuritis and 20 normal controls. The coronal T2 weighted imaging(T2 WI) with fat saturation and enhanced T1 weighted imaging(T1 WI) were performed to evaluate the optic nerve. MRI histogram texture features of the involved optic nerve were measured on the corresponding coronal T2 WI images. The normal optic nerve(NON) was measured in the posterior 1/3 parts of the optic nerve. Kruskal-Wallis one-way ANOVA was used to compare the difference of texture features and receiver operating characteristic(ROC) curve were performed to evaluate the diagnostic value of texture features for the optic nerve impairment among the affected optic nerve with enhancement(ONwEN), affected optic nerve without enhancement(ONwoEN), contralateral normal appearing optic nerve(NAON) and NON. Results The histogram texture Energy and Entropy presented significant differences for ONwEN vs. ONwoEN(both P = 0.000), ONwEN vs. NON(both P = 0.000) and NAON vs. NON(both P < 0.05). ROC analysis demonstrated that the area under the curve(AUC) of histogram texture Energy were 0.758, 0.795 and 0.701 for ONwEN vs. ONwoEN, ONwEN vs. NON and NAON vs. NON, AUC of Entropy were 0.758, 0.795 and 0.707 for ONwEN vs. ONwoEN, ONwEN vs. NON and NAON vs. NON.Conclusion The altered MRI histogram texture Energy and Entropy could be considered as a surrogate for MRI enhancement to evaluate the involved optic nerve and normal-appearing optic nerve in optic neuritis.
基金Project(2016YFB0300605)supported by the National Key Research and Development Program of ChinaProject(51234002)supported by the National Natural Science Foundation of China+1 种基金Project(L2013113)supported by the Liaoning Province Science and Technology,ChinaProject(N140703002)supported by the Fundamental Research Funds for the Central Universities,China
文摘The effects of different solution methods on microstructure, mechanical properties and precipitation behavior of Al-Mg-Si alloy were investigated by scanning electron microscope, transmission electron microscope, tensile test, and differential scanning calorimetry. The results revealed that the recrystallized grains of the alloy after the solution treatment with hot air became smaller and more uniform, compared with solution treatment with electrical resistance. The texture of the alloy after two solution treatment methods was different. More rotated cube components were formed through solution treatment with electrical resistance, which was better for improving the drawability of the alloy. The strength of the alloy under the solution treatment with hot air was higher before stamping, because of the small uniform grains and many clusters in the matrix. The alloy solution treated with hot air also possessed good bake hardenability, because the transformation occurred on more clusters in the matrix.
基金The IOS authors are partially supported by the National High Technology Development 863 Program of China under Grant No.2006AA01Z306the National Grand Fundamental Research 973 Program of China under Grant No.2002CB312102.
文摘Texture optimization is a texture synthesis method that can efficiently reproduce various features of exemplar textures. However, its slow synthesis speed limits its usage in many interactive or real time applications. In this paper, we propose a parallel texture optimization algorithm to run on GPUs. In our algorithm, k-coherence search and principle component analysis （PCA） are used for hardware acceleration, and two acceleration techniques are further developed to speed up our GPU-based texture optimization. With a reasonable precomputation cost, the online synthesis speed of our algorithm is 4000＋ times faster than that of the original texture optimization algorithm and thus our algorithm is capable of interactive applications. The advantages of the new scheme are demonstrated by applying it to interactive editing of flow-guided synthesis.
