查询词典 characteristic

This section presents two kinds of characteristic schemes, one is the natural use of the usual backward Euler characteristic difference scheme ( [60] ) onto the triangular mesh, the other replaces the backward Euler's method by modified Euler formula to approximate the characteristic differential equation, so that the discretization for characteristic curve can get up to second order accuracy.

本节给出了两种三角形网格上的特征差分格式，第一种是通常的向后Euler型特征差分格式（[60]）在三角形网格上的自然运用，第二种采用§3.3、§3.4的离散思想，使用改进的Euler公式代替向后Euler公式来近似特征微分方程，使其对特征线的离散达到了二阶精度。

Materials and Methods:236 pathology-confirmed breast lesions(155 malignanty,81 benignancy) and 221 disease-free contralateral breast tissues were examined using EPI-DWIb values=0,1000 s/mm~2TR/TE=8400ms/93.8ms; FOV=30×30cm;matrix=128×128;ASSET=2,slice thickness=4mm.DCE-MR imaging was also performed for accurate location of the lesion using VIBRANT sequence.The mean ADC values of malignant and benign lesions and the disease-flee contralateral breast tissues were calculated from the ADC map for each patient.One-way analysis of variance was applied to compare the mean ADCs of malignant lesions with benign lesions and disease-flee contralateral breast tissues.The threshold ADC value for malignant lesion was determined using a receiver operating characteristic(ROC curve analysis.Each lesion was classified into two major types:mass and non-mass lesion.The diagnostic performance of DWI was compared in breast mass and non-mass lesions.Results:155 malignant and 81 benign lesions were confirmed in 236 lesions.

材料与方法：搜集术前行乳腺MR检查并经穿刺或手术病理证实的236例乳腺病变，以对侧正常乳腺腺体作为正常对照，采用横轴位的平面回波-扩散加权成像序列，TR=8400ms，TE=93.8ms，层厚=4mm，激励次数=2：视野=30×30cm，矩阵=128×128，ASSET=2，b值=0和1000s/mm~2；参考动态增强图像准确定位，测量病变区和对侧正常乳腺腺体的ADC值，应用t检验比较良、恶性病变及正常腺体ADC值的差异，采用接收者工作特征曲线(receiver operating characteristic curve，ROC)确定良恶性病变的ADC界值；根据BI-RADS MRI将乳腺病变按照形态学表现分为肿块性病变和非肿块性病变两组，比较ADC值在肿块和非肿块性病变中定性诊断的效能。

The thesis adopts phantom tests with ROC (Receiver operating characteristic) curve analysis to compare cross correlation analysis method with coherence analysis method on Bruker MedSpec 3T system and according to the advantage of coherence analysis method to analysis conventional fMRI and resting-state fMRI.

论文中先采用仿体测试搭配ROC(Receiver operating characteristic)曲线分析比较相关系数法与同调性分析法在Bruker MedSpec 3T system上的表现再根据同调性分析法的优点分析功能性的影像与平静状态功能性影像。

By using correlation analysis, we are able to calculate the self correlation coefficient of the same characteristic value to achieve the association of current and previous one and the cross correlation coefficient of two different characteristic values, consequently achieve the data association between characteristic values. 3. On the characteristic level, we are trying to fuse the characteristic values from different data source and identify the exact type of the fault.

用同种类多个传感器进行测量，得到的数据以加权自适应估计方法将它们融合处理得出最佳值；对来自异类多个传感器的数据进行最小二乘估计处理将它们融合到一起，完成数据关联和从测量数据估计出它们所反映的特性；通过计算征兆数据的自相关系数能完成同一征兆当前值与过去值的关联，又可以通过计算两个征兆数据的互相关系数完成这两个征兆的关联。

From macro to micro and from qualitative to quantitative evaluation, this paper, applicating the theory and technological method of sequence stratigraphy、seismic stratigraphy、 reservoir sedimentology, combining with multispecialty and mutisubject theory that used geology, log, seismic, mathematics and earth physics and basing on synthetic application of regional geology, core, log, seismic and petrophysical property data, has studied the inner structure and characteristic of sequence、system tract and depositional system. Combining with high resolution seismic data and log data, this paper makes a profound analysis of the space pattern and reservoir predictability of depositional system on oil and gas pools of honghaoersute sag.

中文题名陆相断陷湖盆层序地层特征与油气勘探副题名以二连盆地洪浩尔舒特凹陷下白垩统为例外文题名 Terrigenous sequence stratigraphy characteristic hydrocarbon exploration of fault-depressed lacustrine basin：a case study of early cretaceous，Honghaoersute sag，Erlian basin 论文作者谭荣导师赵霞飞教授杜金虎教授级高级工程师学科专业矿产普查与勘探研究领域\研究方向陆相层序地层学与区域油气评价学位级别博士学位授予单位成都理工大学学位授予日期2002 论文页码总数128页关键词层序地层油气勘探二连盆地洪浩尔舒特凹陷油气藏馆藏号BSLW /2002 /P618.13 /325 本文采取从宏观到微观，从定性到定量的研究思路，应用层序地层学、地震地层学、储层沉积学的理论和技术方法，结合区域地质、岩芯、测井、地震、物性资料，采用多专业、多学科理论和方法相结合。

Based on investigating the short and intermittent structural plane, surrounding rockmass of the huge underground powerhouse in Three Gorge has been divided into five statistical similar areas according to its characteristic of rockmass structure by applying structure plane network simulation. Distributed characteristic of structural plane has been studied and based on it mechanics macrocharacteristic has been studied:(1) It is the first time that based on the result of structural plane network simulation rockmass quality of every structure area has been studied with applying blurred information optimum seeking technique and be compared with and RQD method. The result indicated that it has better effect to evaluate rock quality with blurred information optimum seeking technique.(2) It is the first time that the interrelated relationship of the result of in-suit rockmass deformation test and fractal characteristic of structure on test point has been applied to determine rockmass deformation parameter. The question of evaluating deformation parameters of engineering rockmass has been solved.(3) Anisotropy strength parameters have been determined by applying shear zones simulating method. The result indicated that there are different strength parameters in every structural area, after comparing the result of Fast Lagranian Analysis in continua number simulation method with that of method of weighted mean according to continuity. The result indicated that when a suitable reduction coefficient is been considered rockmass strength parameters can be simply and fast determined with method of weighted mean according to continuity where there is not enough test result.(4) Damage characteristic has been studied based on analysis fractal characteristic of structural plane network by applying fractal-damage coupling method. It is the first time that the concept of damage degree has been set up to evaluate rockmass quality according to the biggest principal damage.

通过对短小、断续性结构面统计特征的研究，将地下厂房区划分为五个岩体结构统计均质区，应用结构面网络模拟技术研究了各个岩体结构均质区结构面的发育分布特征，并以此为基础对岩体宏观力学特性进行了深入研究：(1)首次通过在结构面网络模拟计算结果的基础上，应用模糊信息优化技术研究了厂房区各个岩体结构分区的岩体质量并与岩体基本质量指标研究法、岩体质量指标RQD值研究法作了对比，结果表明以结构面网络模拟结果为基础，应用模糊信息优化技术进行岩体质量评价能够取得很好的效果，解决了工程岩体质量的定量评价问题；(2)首次通过对已有的现场大型岩体变形试验结果的分析及相应试验点岩体结构分形特征的研究，建立了结构面分布的分形维数和岩体变形指标间的相关关系，并首次应用这种相关关系根据结构面网络模拟及分形维数计算结果确定了缺少试验结果的地下厂房各工程部位的岩体变形指标而且应用于围岩稳定性计算，解决了工程岩体宏观变形参数的评价问题；(3)应用在结构面模拟网络图上模拟岩体剪切破坏带的方法，得出了岩体在不同方向上的强度参数，结果表明岩体的强度特性与结构面的发育方向和程度有着明显的关系，各个岩体结构均质区具有不同的强度参数；同时还通过应用拉格朗日差分法对岩体强度指标的数值分析并与按连通率加权平均计算法对比表明，按连通率加权平均计算法在考虑合理的折减系数情况下，可以简单快速地对缺少现场大型试验结果的具体工程部位实现岩体强度指标的估计，通过以上研究解决了工程岩体抗剪强度参数的评价问题；(4)通过结构面网络分形维数的研究，应用分形损伤耦合分析方法，研究了厂房区岩体的损伤特征，并首次引入"损伤度"的概念，建立了应用最大主损伤评价岩体质量的指标体系。

The probe was tone burst and its frequency was the same as neuronal characteristic frequency . The effects of different maskers on the minimum threshold, response latency, dynamic range and firing rate of the mouse inferior colliculus neurons were observed in the experiment.20 healthy adult mice 20-25 g.

探测声频率为神经元的特征频率(characteristic frequency， CF)，掩蔽声分别为和神经元CF相同的短纯音掩蔽声和上扫调频掩蔽声(up-sweep frequency modulation masker)。

As the complete characteristic curves of reversible pump turbine are often used to calculate the instantaneous parameters, this paper studies the characteristic curve and the wicket closure and opening law in pumped storage plants.Chapter 1 presents the importance and the necessity of this study and reviews the previous related research on hydraulic transient process and valve regulation in pumped storage plants.Chapter 2 analyzes the six collected characteristic curves of reversible pumped turbine and studies their diversification from the point of view of specific speed. The six collected discharge and moment curves with maximum efficiency have been fitted to piecewise continuous curves. This curve-fitting procedure is listed.Chapter 3 takes Liyang Pumped storage plant as an example and analyzes the effect of different characteristic curves on regulation guarantee parameters and the variety of its trochoid during the same operation status.Chapter 4 takes three pumped storage plants with different heads as examples and studies the characteristic of coordinated closure with wicket gate and ball valve and its effect on dynamic pressure in the spiral case, inlet pressure in the draft tube and the rise of rotating speed.Chapter 5 summarizes this paper and point out what should be done in the future research.

由于在过渡过程分析计算中，需要频繁利用可逆式机组的全特性曲线推求机组的瞬时参数，所以本文就特性曲线及关闭规律问题进行了研究，其主要内容如下：第1章，指出本文研究的意义和目的，回顾前人对水力过渡过程、抽水蓄能电站及阀调节的研究成果，在此基础上提出本文的研究内容；第2章，针对收集到的六套特性曲线，从比转速的角度出发来研究可逆式机组特性曲线的变化规律；并对六套曲线的最高效率流量和力矩曲线进行分段拟合，得到各分段函数的具体形式，再通过举例说明最高效率曲线的拟合步骤；第3章，以溧阳抽水蓄能电站为实例，分析讨论不同比转速特性曲线对调保参数造成的影响及对于相同工况其轨迹线的变化；第4章，结合高、中、低三水头段抽水蓄能电站，在导叶直线关闭的基础上，研究导叶与球阀协联关闭规律的特点及对蜗壳动水压力、尾水管进口压力及转速上升造成的影响；第5章，总结全文，提出今后研究的重点和方向。

The findings indicated that, the Japonica rice RVA profile characteristic is the concurrently Indica rice nature with the glutinous RVA profile characteristic continuously change body, assumes 5 kind of characteristics class groups, the few idioplasms has the glutinous starch RVA profile characteristic, also has some idioplasms for the starch RVA profile characteristic of Indica rice, the partial idioplasms have the high quality RVA profile characteristic, namely setback for the negative value, the overwhelming majority idioplasm RVA profile characteristic approx

研究结果表明，粳稻的RVA谱特征是兼具籼性与糯性RVA谱特征的连续变化体，呈5种特征类群，少量种质具有糯性淀粉RVA谱特征，即还有一些种质表现出为籼性淀粉RVA谱特征，部分种质具有优质的RVA谱特征，即消减为负值，绝大多数种质的RVA谱特征(约占样本数的85%)，其曲线的显著特征为消减值在250-1000cp。籼稻的RVA谱特征的分化亦呈现为多态性，主要表现为峰值粘度、最终粘度与消减值的分异性，在籼稻种质材料中主体RVA谱类型的特征表现为消减值在1000-2000cp间。特异的分化出3种类型，第一类表现为峰值粘度与消减值均在2000cp

Soil water characteristic curve is one of important parameters for modeling waterflow and solutes transport.

0引言土壤水分特征曲线(soil water characteristic curve，SWCC)是表示土壤水吸力和土壤含水量之间关系的曲线，是模拟土壤水分运动和溶质迁移的重要参数之一。

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。