考虑速度分量的各向异性进行能量估计,得到三维稳态Q-tensor液晶流系统的Liouville型定理,即若u∈L^(q)(R^(3))∩˙H^(1)(R^(3)),u_(i)∈L xi q/q−2 L s xei(R×R^(2))(i=1,2,3),且Q∈H^(2)(R^(3)),其中2/q+1/s≥1/2,1≤s≤∞,2<...考虑速度分量的各向异性进行能量估计,得到三维稳态Q-tensor液晶流系统的Liouville型定理,即若u∈L^(q)(R^(3))∩˙H^(1)(R^(3)),u_(i)∈L xi q/q−2 L s xei(R×R^(2))(i=1,2,3),且Q∈H^(2)(R^(3)),其中2/q+1/s≥1/2,1≤s≤∞,2<q<∞,则该稳态系统只有平凡解.这个结论推广了已有的结果.展开更多
Tracking of crossing WM fiber bundles can be resolved using diffusion MRI imaging. DTI can only resolve a single fiber orientation within each voxel due to the constraints of the tensor model. DSI requires large pulse...Tracking of crossing WM fiber bundles can be resolved using diffusion MRI imaging. DTI can only resolve a single fiber orientation within each voxel due to the constraints of the tensor model. DSI requires large pulsed field gradients and time-intensive sampling. This paper puts forward with a new method based on QBI, which uses a spherical tomographic inversion called Funk-Radon transform to get high angular resolution diffusion imaging signal. From the tracking results, we can get the conclusion that QBI-tracking can resolve crossing fiber time-savingly.展开更多
This paper deals with the class of Q-tensors, that is, a Q-tensor is a real tensor ,4 such that the tensor complementarity problem （q, A）： finding an x ∈R^n such that x ≥ 0, q＋Axm-1 ≥ 0, and xT（q＋Ax^m-1） = 0...This paper deals with the class of Q-tensors, that is, a Q-tensor is a real tensor ,4 such that the tensor complementarity problem （q, A）： finding an x ∈R^n such that x ≥ 0, q＋Axm-1 ≥ 0, and xT（q＋Ax^m-1） = 0, has a solution for each vector q ∈R^n. Several subclasses of Q-tensors are given： F-tensors, R-tensors, strictly semi-positive tensors and semi-positive R0-tensors. We prove that a nonnegative tensor is a Q-tensor if and only if all of its principal diagonal entries are positive, and so the equivalence of Q-tensor, R-tensors, strictly semi-positive tensors was showed if they are nonnegative tensors. We also show that a tensor is an R0-tensor if and only if the tensor complementarity problem （0, A） has no non-zero vector solution, and a tensor is a R-tensor if and only if it is an R0-tensor and the tensor complementarity problem （e,A） has no non-zero vector solution, where e = （1, 1…. , 1）T展开更多
文摘考虑速度分量的各向异性进行能量估计,得到三维稳态Q-tensor液晶流系统的Liouville型定理,即若u∈L^(q)(R^(3))∩˙H^(1)(R^(3)),u_(i)∈L xi q/q−2 L s xei(R×R^(2))(i=1,2,3),且Q∈H^(2)(R^(3)),其中2/q+1/s≥1/2,1≤s≤∞,2<q<∞,则该稳态系统只有平凡解.这个结论推广了已有的结果.
基金Supported by the National Natural Science Foundation of China(62173308,61973078)the Natural Science Foundation of Zhejiang Province of China(LR20F030001,LD19A010001)。
文摘Tracking of crossing WM fiber bundles can be resolved using diffusion MRI imaging. DTI can only resolve a single fiber orientation within each voxel due to the constraints of the tensor model. DSI requires large pulsed field gradients and time-intensive sampling. This paper puts forward with a new method based on QBI, which uses a spherical tomographic inversion called Funk-Radon transform to get high angular resolution diffusion imaging signal. From the tracking results, we can get the conclusion that QBI-tracking can resolve crossing fiber time-savingly.
基金supported by the National Natural Science Foundation of China(Grant No.11571095,11601134)the Hong Kong Research Grant Council(Grant No.PolyU502111,501212,501913 and 15302114)
文摘This paper deals with the class of Q-tensors, that is, a Q-tensor is a real tensor ,4 such that the tensor complementarity problem （q, A）： finding an x ∈R^n such that x ≥ 0, q＋Axm-1 ≥ 0, and xT（q＋Ax^m-1） = 0, has a solution for each vector q ∈R^n. Several subclasses of Q-tensors are given： F-tensors, R-tensors, strictly semi-positive tensors and semi-positive R0-tensors. We prove that a nonnegative tensor is a Q-tensor if and only if all of its principal diagonal entries are positive, and so the equivalence of Q-tensor, R-tensors, strictly semi-positive tensors was showed if they are nonnegative tensors. We also show that a tensor is an R0-tensor if and only if the tensor complementarity problem （0, A） has no non-zero vector solution, and a tensor is a R-tensor if and only if it is an R0-tensor and the tensor complementarity problem （e,A） has no non-zero vector solution, where e = （1, 1…. , 1）T
