查询词典 delta function

The project will develop a bandpass sigma-delta analog-to-digital converter for digital audio broadcasting system in three years. In the first year, we had finished the system simulation for IF receiver using conventional high speed ADC and bandpass sigma-delta ADC, respectively. We also had done the analysis and design of high-order bandpass sigma-delta modulator structure. In this year, we have developed a coefficient synthesis method for high order bandpass sigma-delta modulator using high order filter transfer functions (inverse Chebyshev bandreject filter function).

本计划将在三年内发展一个能应用在数位音讯广播系统的带通sigma-delta类比/数位转换器(analog-to-digital converter，ADC)，在第一年度中我们分别以传统高速类比/数位转换器及带通SD类比/数位转换器的接收系统为例，并结合编码正交多工器(Coded Orthogonal Frequency Division Multiplex，COFDM)的技术，建立一套DAB系统模拟的方法，同时并研究有关高阶带通SD类比/数位调变器的架构及电路，并已成功开发出一个由高阶滤波器合成的高阶带通调变器。

The affected chicks acquired the morphine conditioned place preference more quickly, and maintained it much longer. Experiment 3 showed that during E5-8, injecting delta receptor antagonist naltrindole reversed the learning and memory impairment caused by morphine while delta receptor agonist DPDPE impaired learning and partial memory function. On the other hand, mu opioid receptors had little effect. As for E17-20, given naloxonazine can reverse the increases of susceptibility to morphine, and the mu receptor agonist DAGO cause the increases of susceptibility to morphine. Delta receptors have no effect.

研究结果发现：经过对鸡胚发育不同时间段的吗啡给药，胚胎期发育E5-8阶段给予吗啡的小鸡学习记忆受损最为严重，表现为学习和记忆功能的严重下降；而E17-20时段吗啡给药的小鸡更容易获得吗啡CPP且保持时间更长。E5-8阶段给予delta受体拮抗剂natrindole能够翻转吗啡对学习和记忆的损害作用，并且给予delta受体激动剂DPDPE也损害学习和部分记忆功能，mu受体作用不大。E17-20阶段拮抗mu受体能够抑制成瘾易感性的增加，激动mu受体可以增加小鸡的成瘾易感性，delta受体没有明显作用。

Advanced vibration on the UH-60 Blackhawk or agents of the intuitive control, as well as the map is the function of "Delta Corps" game of the additional features.

先进的振动，对 UH-60 Blackhawk 或特工的直觉控制，以及地图功能是"Delta Corps"游戏的额外特色。

It turned out that hematopoietic stem cells be immortalized by constitutive Notch1 and Delta has the function as the mitogenic regulators of hematopoietic stem cells.

研究人员将活化形式Notch受体导入造血干细胞，使其获得了细胞因子依赖性的"永生"；另外，Notch的配体Delta、Jagged具有类有丝分裂因子作用，可保持造血干细胞的自我更新能力，促进其体外增殖。

However, its accuracy is not much high in interpolation. On the other hand, interpolation functions in the point interpolation method have delta function property, and it is convenient to apply the essential boundary conditions.

而点插值方法的插值函数具有Delta函数性质，可以很方便的施加本质边界条件，不利之处是在计算插值函数时矩阵易于奇异。

In the context of signal processing it is often referred to as the unit impulse function. Note that the Dirac delta is not strictly a function. While for many purposes it can be manipulated as such, formally it can be defined as a distribution that is also a measure .

在物理上，通常用于代表脉冲函数，或者呈点分布的物理量，例如质点、点电荷等；另外，delta函数常用于表示对物理量在某点的抽样，这一点不仅在数学物理方法这样的理论学科中常用，在实际的工程通信中也很常用，这时delta函数被用作采样函数。

The shape function obtained in the trail function had the Kronecker Delta property. and no additional treatment were required to impose essential boundary conditions.

构造成的形函数具有Kronecker Delta性质，不再需要额外的处理来施加本质边界条件。

Boundary polynomial point interpolation mesh-free method and boundary radial point interpolation mesh-free method were presented, based on polynomial basis and radial basis respectively for transient eddy current analysis, and their interpolation shape functions satisfy the Kronecker delta function and the essential boundary conditions can be directly imposed on the boundary nodes. An example on analyzing transient eddy current of a square metal column was set to prove the validity of the proposed methods, and a comparison on accuracy between BPPIM and BRPIM was analyzed as well.

运用多项式点插值法和径向基点插值法构造形函数，推导了适合于工程电磁场瞬态涡流问题的多项式基点插值边界无单元方法和径向基点播值边界无单元方法，这两种方法的空间插值形函数满足Kronecker delta条件，从而强加边界条件可以直接施加在边界点上，以金属长方柱的瞬态涡流分析作为数值算例，证实了两种方法的正确性和有效性，并对两种基类的点插值法进行了精度分析和比较。

Results show that radial basis function and point interpolation methods possess Kronecker Delta function property, but the robustness is poor in some cases; the MLS approximation function does not possess Kronecker Delta function property, but it has good robustness. Differences among the three discretization schemes of meshless method are as follows:the collocation method requires no numerical integration and very little computational time while its robustness is poor; Galerkin method is not a truly meshless method due to the background meshes required for integration; the Petrov-Galerkin method is a truly meshless method and need numerical integration in each sub-domain, so it needs more computational time.

分析结果显示：径向基函数和点插值法均具有d 函数属性，但计算稳定性差；移动最小二乘近似函数不具有d 函数属性，但计算比较稳定；无网格方法中的3种离散方法不同之处在于：配点法不需要积分，计算量小，计算稳定性差；Galerkin方法需要借助背景网格进行积分，它不是真正的无网格方法；Petrov-Galerkin方法，是一种真正的无网格方法，它需要对每个子域进行积分，计算工作量较大。

The strain and temperature resolution is 30με and 3℃, respectively. 6. Several typical demodulation method using optical filters, including quasi delta function demodulation, linear function demodulation, matrix function demodulation and trigonometric function demodulation, is presented and discussed. We research the matched-grating demodulation and a high wavelength resolution of 2. 6pm is reached.

分析和归纳了几类较为典型的滤波解调制方法（包括：类δ函数解调制、线性函数解调制、矩形函数解调制和三角函数解调制），对这几类方法如何实现做了简单讨论，并对匹配光栅解调解调技术进行了理论分析和实验研究，这种检测方案的波长分辨率可达2.6pm。

The absorption and distribution of chromium were studied in ryeusing nutrient culture technique and pot experiment.

采用不同浓度K2CrO4(0，0.4，0.8和1.2 mmol/L)的Hoagland营养液处理黑麦幼苗，测定铬在黑麦体内的亚细胞分布、铬化学形态及不同部位的积累。

By analyzing theory foundation of mathematical morphology in the digital image processing, researching morphology arithmetic of the binary Image, discussing two basic forms for the least structure element: dilation and erosion.

通过分析数学形态学在图像中的理论基础，研究二值图像的形态分析算法，探讨最小结构元素的两种基本形态：膨胀和腐蚀；分析了数学形态学复杂算法的基本原理，把数学形态学的部分并行处理理念引入到家实际应用中。