查询词典 second derivative

Since the B-spline is a locally supported function, the smoothing formula can be strictly limited in a neighborhood of each point. The smoothing surface defined by the smoothing formula has the same convexity as that of the original image. Secondly, the edge points are detected by either computing the local extremum points of the directional derivative or computing zero-crossing of the second-order directional derivative of the smoothing surface. Finally, an example of an edge detector is given.

针对反卷积视觉模型的病态性，增加了适当的约束，给出了基于低松弛迭代格式的快速自适应滤波算法，对于一个N×N输入图象，由于变换核的局部支撑性质以及低松弛迭代格式的引入，使得快速自适应滤波算法的计算复杂度降为象素个数N〓的线性量阶N〓，就最小二乘算法的复杂性而言，优于不动点迭代算法的O以及基于FFT的预处理共轭梯度算法的O。

The first rank derivative is a reflection of curve change and its rate, at certain range, if the sign of the first rank derivative has changed, the logging value of the correspondence depth point means maximum in this range; the second rank derivative is the knaggy property reflection of curve, at certain range, if the sign of the second rank derivative has changed, the correspondence depth point represent the inflexion of geophysical logging curve, it＇s also a turning point of the reflection of knaggy change property of the curve, it is the interface of stratum.

测井曲线的值是深度的函数，测井曲线的一阶导数表示了曲线变化的趋势和变化的快慢，在某一范围内，当一阶导数呈现符号转换时，相对应的深度点的测井值即为该范围内极大值；测井曲线的二阶导数则表示曲线的凹凸性，在某一范围内，当二阶导数呈现符号转换时，相对应的深度点代表了测井曲线的拐点，即反映曲线凹凸性变化的转折点，亦即地层的分界面。

A new data analysis method was proposed to analyze the separated probe data based on the method of the integration of the second derivative the probe current.

为了采用探针电流二次微分积分法分析等离子体参数，对于离散的探针测量数据，提出了一套新的分析方法。

The second derivative spectroscopy and Gaussian fitting fluorescence spectroscopy are effective methods to monitor changes in structural characteristics of proteins.

本文研究结果表明，荧光光谱结合导数光谱分析和高斯拟合光谱方法是分析蛋白质构象及功能变化的有效方法。

Triose phosphate isomerase was prepared and purified from chicken breast muscle. The equilibrium unfolding of TIM induced by guanidine hydrochloride was investigated by following the changes in intrinsic fluorescence, circular dichroism and second-derivative spectroscopy.

从鸡胸肌中纯化出磷酸丙糖异构酶(triose phosphate isomerase， TIM)，通过蛋白质内源荧光，圆二色性，紫外吸收二阶导数光谱等多种研究溶液构象的方法，对TIM被盐酸胍和热变性过程进行了详细的研究。

Methods Using LineGene fluorogenic quantitative PCR detection system to detect HBV DNA of 77 patients and second derivative maximum method and fit point method to analyze results.

用LineGene FQD33A型荧光定量PCR检测系统检测本院门诊和病房乙肝病人血清HBV DNA 77份，分别用最大二阶导数法和样点拟合法进行结果分析。

After convolving the image model with the edge detection operators of second derivative model, a plane fitting in the least squares sense is used to detect the zero crossing points as edge points.

使用二阶导数型边缘检测算子对图象模型进行卷积后，用均方误差最小的准则对卷积后的图象进行平面拟合，并求出零交点作为图象的边缘点。

Evidence suggests that 1 under more stable stratification, the basic flow, if moving faster at low and high levels (particularly in the presence of jets there), allows a resulting meso-β unsteady wave to propagate eastward with respect to basic flow and even at greater velocity compared with it; 2 vertical windspeed shear of basic flow causes instabilities of the TWT perturbation; 3 considering the second derivative of basic-flow wind with respect to z (denoted by zz≠ 0 which is simply given as β* hereafter) the expression for the phase velocity of vortex Rossby wave is obtained, which is unidirectional in propagation with respect to basic flow; 4 VRoW has its physical origin from β*, i.e., from z-varying heterogeneities of y-direction averaged vorticity of the basic flow field; 5 VRoW phase velocity is associated with zonal wave number k, its energy is dispersive and the group velocity exists in the x direction; 6 when windspeed meets the condition of β*, TWT disturbance instability may be that of mixed VRoW and gravity wave; 7 if basic flow is subject to linear shear but does not meet the condition of β*, the TWT instability is that of inertia-gravity wave.

在大气层结比较稳定的情况下，如果基本气流在低层和高层较大(有可能存在低空急流和高空急流)，此时产生的β中尺度不稳定扰动相对于基流向东传播，甚至于快速向东传播。基本气流在垂直方向上的风速切变对于中尺度横波型的扰动起着不稳定的作用。如果考虑基流的二次切变，可以得到涡旋Rossby波的相速度表达式，涡旋Rossby波相对于基本气流是单向传播的。涡旋Rossby波产生的物理根源是基本流场的风速二次切变，亦即基本流场y方向的平均涡度在空间z方向上的不均匀所致。涡旋Rossby波的相速度与纬向波数也有关，它的能量是频散的，其在纬向x方向也存在群速度。在基本流场的风速存在二次切变时，横波型不稳定可能是混合的涡旋Rossby重力波的不稳定；而在基本流场的风速仅仅存在线性切变，不存在二次切变时，横波型扰动的不稳定则是重力惯性波的不稳定。

After the comparison of the theories and data analysis methods, it is considered that the method of the integration of the second derivative the probe current was suitable to diagnose the high pressure (about 10 torrs) glow discharge plasma.

论文对当前广泛采用的等离子体探针诊断理论和数据分析方法进行了对比，认为在低真空度条件下，探针电流二次微分积分法比较适用。

The NIR spectra data of wood meal was transformed into second-derivative mode.

造纸木材原料由于成分含量和结构的差别而具有不同的制浆造纸性能。

Breath, muscle contraction of the buttocks; arch body, as far as possible to hold his head, right leg straight towards the ceiling (peg-leg knee in order to avoid muscle tension).

呼气，收缩臀部肌肉；拱起身体，尽量抬起头来，右腿伸直朝向天花板（膝微屈，以避免肌肉紧张）。

The cost of moving grain food products was unchanged from May, but year over year are up 8%.

粮食产品的运输费用与5月份相比没有变化，但却比去年同期高8％。