查询词典 coefficient of diffusion

objective to obtain the diffusion tensor maps of the normal human brain,and assess intrinstic properties of water diffusion in quantitative parameters for an anatomic analysis.methods maps of isotropic apparent diffusion coefficient and various anisotropic maps were calculated in60healthy adults from seven diffusion imagings by using single-shot echo-planar diffusion-weighted sequence.brain parenchyma anatomy was analyzed and adciso and various anisotropic index were measured.results （1）diffusion properties of different tissues and anatomic areas of normal adult human brain are different.diffusion in white matter is anisotropic;diffusion in gray matter is isotropic.

目的 获取正常人脑组织扩散张力性图像（diffusion densor imaging，dti），定量分析正常人脑组织水扩散的内在特性，进一步评价脑解剖结构。方法 60例健康正常人，应用单次激发epi-dw序列，计算出adciso图及各向异性图，分析脑实质不同区域的解剖结构，测量adciso（isotropic apparent diffusion coefficient）及各向异性指数。结果（1）脑内不同组织结构弥散特性不同，脑白质弥散表现为各向异性，而脑灰质弥散表现为各向同性。

Based on the above-mentioned parameter, according to the relationship between robust estimation and nonlinear diffusion, the Turkey loss function is introduced as the diffusion function in SAR image decomposition because of its better performance, and the contour of an image is extracted by the Turkey diffusion function with the proposed diffusion parameter mentioned above. The experiment results indicate that the Turkey loss function based diffusion process can strengthen the conspicuous contour. Additionally, a Raita\'s criterion-based method, solving the automatic diffusion threshold, is proposed to automatically set the threshold in diffusion decomposition.

针对基于梯度参数和局域方差系数的扩散在对SAR图像进行分解时存在的缺陷，提出了一种局域方差系数与窗口幅度均值积的扩散系数，该系数能够更有效地实现潜在目标区域和背景区域的区分；在此基础上，根据鲁棒估计与非线性扩散的联系，引入扩散效果更好的Turkey损失函数作为图像分解中的扩散函数，并结合局域方差系数与窗口幅度均值积的扩散参数来提取图像的轮廓，结果表明：基于Turkey损失函数的扩散过程对特征突出的边缘所起的&强化作用&更加明显；此外，针对扩散分解中的阈值确定问题，提出了一种基于拉依达准则的扩散阈值自动求解方法，实现了扩散阈值的自动求解。

A numerical calculation program is written up for the various solution methods in this paper and the program is being used in various aspects of inverse problem of environmental hydraulics, including inverse problem in reverse process of one-dimensional unstable diffusion, inverse problem in reverse process of convection-diffusion, inverse problem for the dispersion coefficient in water quality model, The inverse problem of coefficient identification for nonlinear Boussinesq equation, parameter identification inverse problem for water quality model, the inversion of parameter of BOD-DO water model, the inverse problem of the source of convection-diffusion, identification of the steady-state permeability for two dimensional isotropic medium, two-dimensional steady inverse problem of convection-diffusion and parameter identification inverse problem for two-dimensional parabolic equation, etc.

对本文提出的各种算法，编制了数值计算程序，并把它应用于环境水力学反问题诸多领域，包括污染物一维非恒定扩散逆过程反问题，对流扩散方程逆过程反问题，河流水质纵向弥散系数反问题，非线性Boussinesq方程反问题，河流水质多参数识别反问题，BOD-DO水质模型参数反演问题，对流—扩散方程源项反问题及二维恒定各向同性介质渗透系数反问题，二维定常对流——扩散方程及二维抛物型方程参数控制反问题等。

From the results of different coefficient and similar coefficient,Schima superbashowed high total mean different coefficient and low total mean similar coefficient;Castanopsis chinensis showed high total mean different coefficient and media totalmean similar coefficient;Cryptocarya chinensis showed low total mean differentcoefficient and high total mean similar coefficient.

从相异系数和相似系数的计算看，荷木总平均相异系数最大，总平均相似系数最小；锥栗总平均相异系数大，总平均相似系数居中；厚壳桂总平均相异系数最小，总平均相似系数最大。

Diffusion tensor imaging is a kind of new technique after diffusion weighted imaging.DTI can reflect anisotropy hydrone molecular diffusion features of damaged myeloid tissue through measuring apparent diffusion coefficient and fractional anisotropy.Accordingly,we can make more precise and allround estimate about spinal compression on microscopic scale.

磁共振扩散张量成像是继扩散加权成像后发展起来的一种新技术，它通过测量表观扩散系数及部分各向异性值来反映损伤脊髓组织的各向异性水分子扩散特征，从而在微观水平对脊髓压迫症做出更精确和全面的评价。

The results showed that the environmental temperature and the direction of particle paving were key factors influencing diffusion coefficient.With environmental temperature increasing,the moisture diffusion coefficient enlarge evidently,and the diffusion efficient parrel to the particleboard surface is higher than that verticle to the particleboard surface.

结果表明：环境温度和刨花的铺装方向是影响扩散系数的主要因素，随着环境温度的提高，水分扩散系数明显增大：平行于板面的扩散系数高于垂直板面的扩散系数。

The new model adapts an operator like coherence enhancement diffusion for edge orientation, and defines eigenvalues based on edgers orientation such that the new tensor has positive diffusion coefficient in edge direction and negative diffusion coefficient in gradient direction.

采用类似相干增强扩散的边缘定向算子实现对边缘的定向，然后根据边缘定向的结果设置扩散张量的特征根，使扩散张量沿边缘方向为正向扩散以增强边缘，而垂直于边缘方向为逆扩散以锐化边缘。

Methods:(1) The two-sided ovary of female animal and the two-sided testicle of male animal were excised. After the XLGBC to treat 28 days, the estradiol and the teststerone of serum were checked;(2) With intramuscular injection the Hydrocortisone,the Yangxu animals was made. After the XLGBC to treat 10 days, the testicle coefficient,the spermathecal gland coefficient and the ovary coefficient were observed;(3) With ig the Thyroid tablets and the Reserpine, the Yinxu animal was made. After the XLGBC to treat 10 days, the testicle coefficient,the spermathecal gland coefficient and the ovary coefficient were observed.

（1）雌性动物摘除双侧卵巢，雄性动物摘除双侧睾丸，复制成去势动物模型后予仙灵骨葆胶囊治疗28天，检测血清雌二醇和血清睾酮；（2）肌注氢化可的松，复制成阳虚动物模型后予仙灵骨葆胶囊治疗10天，观测并计算动物的睾丸系数、精囊腺系数和卵巢系数；（3）灌胃甲状腺片和利血平，复制成阴虚动物模型后予仙灵骨葆胶囊治疗10天，观测并计算动物的睾丸系数、精囊腺系数和卵巢系数。

Diffusion problem of a predator-prey model with Holling typeⅡfunctional capturing function is studied. Stability condition is obtained when diffusion is absent, and the effect on stability of positive equilibrium is studied when diffusion is present. In the end, the problem of existence of limit cycle is proved in the first quadrant when diffusion is absent.

针对一类具有HollingⅡ型功能捕获函数的捕食－食饵模型的扩散问题进行了研究，得到了无扩散时正平衡点的稳定条件，以及扩散存在时对正平衡点稳定性产生的影响，最后证明了无扩散时系统在第一象限存在极限环的问题。

Assuming infinite diffusion medium, based on the diffusion equation for prestressed concrete structure, and accounting for the effects of concrete chloride binding capacity, time dependence of diffusion coefficients, temperature and moisture, models of chloride diffusion in two-dimensional infinite body with both power function and constant homogeneous boundary conditions were formulated.

针对无限大的扩散介质，以综合考虑氯离子结合能力、氯离子扩散系数的时间依赖性和环境温湿度影响的实际预应力混凝土氯离子方程为基础，分别在常数和幂函数边界条件下，推导出二维氯离子扩散理论的齐次模型。

The production moved off-Broadway to New York City, where she won the Joseph E. Calloway award for her performance, and was profiled in American Theater Magazine as one of ten young theater artists to watch.

生产提出过百老汇的新的纽约市，在那里她赢得了约瑟夫calloway奖，她的表现，并于异型在美国的战区杂志之一， 10战区的青年艺术家观赏。

It's a risk tradeoff, and I believe that adding test support code usually wins.

这是一个风险的权衡，我相信添加测试代码通常会占上风。