查询词典 contrast ratio

To compare the image quality of the three sequences in two groups by One-Way ANOVA and T Test. The qualitative assessment standards include clarity, artifacts, signal uniformity, the conspicuity of enhanced vein and the observable grade of intrahepatic venous branchs. The quantitative assessment standards include SNR and CNR of intrahepatic portal vein and hepatic veins. Furthermore, the anatomy and variations of the intrahepatic portal vein and hepatic veins are statistical analysed.

通过方差分析和T检验分别对A、B组三个序列的图像质量进行比较，评定标准包括清晰度、伪影、信号均匀性、静脉强化程度及肝内静脉分支显示级数等定性指标和肝内门静脉、肝静脉的SNR(Signal-Noise Ratio，信噪比)及CNR(Contrast-Noise Ratio，对比度噪声比)等定量指标。

Material and Methods:From March,2008 to January,2009,250 patients(146 Males and 104 Females,ranged from 18 to 82 years old,mean age was 48 years old) enrolled in the First Affiliated Hospital of Kunming Medical College were performed dual energy scan(Group A,200 patients) and Neuro-DSA scan(Group B,50 patients) using DSCT.The patients were randomly divided into Group A and Group B.Regarding to the justification of scan protocol,100 patients in Group A were selected as sub-group to explore the scan protocol.The image quality Was analyzed both in four categories(4.0/60、4.5/60、4.0/70、4.5/70) of flow rate and total amount of contrast-enhanced material and in three categories(100—150HU、150—200HU、200-250HU) of CT value of left common carotid artery.The comparison of two scan approach was based on image quality,radiation does, postprocessing methods,time of scanning and subtraction and data storage amount.To validate the diagnostic capability of DE-CTA virtual unenhanced images,100 patients in Group A were undergoing head scan both in routine non-contrast program and DE-CTA virtual unenhanced program.Mean CT values,signal-to-noise ratio,image quality,sensitivity of lesion identification,and radiation does were applied to comparison.According to diagnostic results of dual energy of cerebral arterial angiography,62 patients out of 200 patients in Group A were confirmed with cerebral vessel lesions,the results were complied with DSA findings(the time between the two methods were within 1 week).

材料与方法收集2008年3月到2009年1月间在昆明医学院第一附属医院行DSCT CTA检查者250例(男性146例，女性104例，年龄范围18-82岁，平均48岁)，随机分为A、B两组，A组200例行双能量头颅CTA扫描；B组50例行Neuro-DSA扫描。A组前100例按对比剂不同流率和总量分为4组(4.0/60、4.5/60、4.0/70、4.5/70)对图像质量比较；按触发时左颈总动脉内平均CT位分3组(100—150HU、150—200HU、200-250HU)，比较图像质量的差异；对A、B两组血管图像质量、辐射剂量、后处理的方法、扫描和后处理时间及数据的容量进行比较分析；A组中前100例行常规与DE-CTA虚拟平扫的平均CT值、信号噪声比、图像质量、病灶显示情况、辐射剂量的比较分析；A组中行DSA检查62例(两种方法间隔时间均1周内)，比较两种检查方法诊断结果是否符合，并对其中24例动脉瘤行动脉瘤部位、数目、形态、瘤颈显示程度、瘤颈大小及瘤体长径和短径的比较研究。

Laboratory experiments were carried out to study the survival and development of the Harmonia axyridis feeding on Chaito phorus popleti on high insect-resisitance hybrid poplar 741(Pb29) and medium insect-resisitance hybrid poplar 741(Pbl7).The API 741 poplar was used as control.The mortality and development during immature period,adult,baby mass.eclosion and sex ratio of H. axyridis were measured.The results showed that:to contrast The API 741, Chaito phorus popleti on Pbl7 and Pb29 has no significantly impacts on eclosion,pupation, ecdysis,mortality of immature period and pupa stage;Although every development stage of ladybeetles were not affected to ,the pupal duration of ladybeetles was lowered than the control;The body mass,eclosion and sex ratio have no significant difference.

通过利用节肢动物群落及各个亚群落的物种丰富度、个体数、均匀度和优势集中性对多样性指数进行通径分析，表明了高抗Pb29和CK节肢动物群落及各个亚群落多样性指数与均匀度和优势集中性的相关系数最高，与其物种个体数关系最为不密切：对各组分进行通径分析均表明的多样性提高是建立在降低优势集中性和增加均匀度指数的基础上的，而且以优势集中性的直接作用效果较为显著。

The primary studying works and characteristics:1 To summarize reinforcing theory of cement mixing pile composite foundation2 To analyze the primary mechanics characters and changing rules of cement mixing pile, based on analysis of test data both indoor and outdoor.3 To discuss siding frictional resistance, ending resistance, ultimate bearing capacity of simple mixing pile and effectiveness factor of grouped piles, loading ratio of soil between piles under cushion cap of grouped piles and stress ratio of pile and soil and so on, and use many computation method and experimentation method to ensure bearing capacity of mixing piles composite foundation.4 To point out and analyze eight sides flaws and problems of the bearing capacity calculation method of mixing pile compositefoundation which ensured by national and normative method/ formula.5 To apply test results of loading tests and a few settlement observation data, use gray theory to predicate ultimate bearing capacity of deep mixing piles, actual example demonstrate engaging between theoretical predicted value and actual value.6 To apply groovy layerwise summation method to discuss entity piles method, double foundation method, equivalent layerwise summation method and consolidation theoretical method and so on, especially by combination of engineering example, use FEM to calculate or discuss the settlement and changing rules of composite foundation.7 To discuss problems of critical length of composite foundation by combination of engineering example and numerical analysis method, and analyze the contrast of critical length between simple pile load and most area load of composite foundation, not only critical length of composite foundation is relative to modulus ratio between piles and soil, but also upside load distribution area of composite foundation.

主要的研究工作与特色为：(1)总结了水泥搅拌桩复合地基的加固原理；(2)在对室内外试验资料进行统计分析的基础上，系统分析了搅拌桩水泥土的主要力学特性及其变化规律；(3)探讨了搅拌单桩的侧摩阻力、端阻力、极限承载力及群桩效率系数、群桩承台下桩间土荷载分担比及桩土应力比等，提出用多种计算方法并结合试验方法来综合确定搅拌桩复合地基的承载力；(4)明确指出和分析了按国家有关规范的方法确定搅拌桩复合地基承载力所存在的八个方面的缺陷与问题；(5)利用过去没有加载至破坏阶段的载荷试验成果和较少的沉降观测数据，尝试了用灰色理论预测深层搅拌桩的极限承载力，实例表明理论预测值与实测值吻合较好；(6)在常规分层总和法的基础上，探讨了复合地基沉降计算的实体墩基法、双层地基法、等效作用分层总和法、固结理论法等，特别是结合工程实例，用有限元数值计算等方法计算和讨论了搅拌桩复合地基的沉降及其变化规律；(7)结合工程实例，用数值分析方法探讨了复合地基临界桩长的问题，指出和分析了单桩荷载下的临界桩长与复合地基大面积荷载下的临界桩长存在很大的差别，复合地基的临界桩长不仅与桩土模量比有关，而且与复合地基上部荷载分布面积有关。

There was signficant Differences in contrast-to-noise ratio of the experiment group and the control group (11.50±2.32 vs 2.71±0.86, P＜0.01). The same results were derived from 30 rain to 1 hafter contrast agent being injected in distal to heart part of the injured vessel, and the signal decreased 24 h later.

另从犬损伤部位远心端注射对比剂30 min至1 h，也显示了上述成像效果；2 h至4 h血栓信号由明显上升渐见趋缓，延迟24 h信号强度减弱，实验组CNR值与对照组间差异也有统计学意义(10.40±2.15比1.93±0.57，P＜0.01)。

Through analysis of variance, the best mass ratio of different coating material matching is found out: It is the best matching when the mass ratioof red clay membrane urea is 5:7,which can lengthen the eluviationing time for 11 days, reduce the nitrogen eluviationing loss by 16.12%; the amount of the clay quality has no use to lengthen the eluviationing time and the result is not obvious; when the quality ratio of urea and gypsum is 5:8,it can lengthen the eluviationing time for 8 days, reduce the nitrogen eluviationing loss by 23.86%;when the quality ratio of urea and gypsum is 5:7,it can lengthen the eluviationing time for 30 days, reduce the nitrogen eluviationing loss by 16.58% when the contrast urea N is all eluviated out ; it is the optimum matching association; When the quality ratio of the urea and the sulfur is 5:6, which is a optimum proportion ,it can l

根据对淋溶时间、经济成本等的对比，经过方差分析，找出了不同包裹材料的最佳质量比的搭配组合：红胶泥包膜尿素的质量比是5：7时最好，可以延长淋溶时间11天，减少氮素淋溶损失16.12%；粘土质量的多少对延长尿素的释放时间作用不大，效果不明显；石膏和尿素两者的最佳质量比是5：8时，可以延长淋溶时间8天，减少23.86%的氮素淋溶损失；硼砂和尿素的质量比是5：7可以延长淋溶时间30天，当对照尿素N素全部淋出时，减少16.58%的氮素淋出，是最优

The addition of iso-octane extends the knocking limit in equivalence ratio somewhat, however the knock occurrence mainly depends on the total concentration of mixture. Although the operation range in equivalence ratio becomes narrow with the increasing of iso-octane, the maximum load is improved 80% by n-heptane/iso-octane controlled real-time in contrast with the HCCI fueled with n-heptane only.

结果表明：混合燃料HCCI着火以及燃烧相位主要取决于正庚烷实际的燃空当量比；异辛烷的加入对爆震当量比界限有所拓展，但HCCI爆震主要与混合燃料总当量比有关；随着辛烷值比例的提高，导致HCCI运行范围变窄，但是实时调控证明相对纯正庚烷，混合燃料的HCCI燃烧最大负荷提高了80%。

Time courses of signal-to-noise ratio and contrast-to-noise ratio were analyzed.

分析信噪比和对比噪声比的时程。

Filters include cropping, scaling, vertical flipping, horizontal mirroring, expanding to create letterboxes, rotating, brightness/contrast, changing the aspect ratio of the video's pixels, colorspace conversion, hue/saturation, color-specific gamma correction, filters for reducing the visibiltiy of compression artifacts caused by MPEG compression, automatic brightness/contrast enhancement, sharpness/blur, denoising filters, and several different ways of deinterlacing.

滤镜包括剪裁，缩放，垂直翻转；均衡器，拓展到创建字元框，旋转，亮度/对比度，改变视频横纵比；颜色空间转换，色调/饱和度，色彩特定伽马校正器；有的滤镜是为减少MPEG压缩处理造成的清晰度下降（去块， deringing ），自动亮度/对比度增强，锐利/模糊，去噪滤波器，和几个不同的扫描方式。

Filters include cropping, scaling, vertical flipping, horizontal mirroring, expanding to create letterboxes, rotating, brightness/contrast, changing the aspect ratio of the video's pixels, colorspace conversion, hue/saturation, color-specific gamma correction, filters for reducing the visibiltiy of compression artifacts caused by MPEG compression, automatic brightness/contrast enhancement, sharpness/blur, denoising filters, and several different ways of deinterlacing.

滤镜包括剪裁，缩放，垂直翻转；均衡器，拓展到创建字符框，旋转，亮度/对比度，改变视频横纵比；颜色空间转换，色调/饱和度，色彩特定伽马校正器；有的滤镜是为减少MPEG压缩处理造成的清晰度下降（去块， deringing ），自动亮度/对比度增强，锐利/模糊，去噪滤波器，和几个不同的扫描方式。

Finally, according to market conditions and market products this article paper analyzes the trends in the development of camera technology, and designs a color night vision camera.

最后根据市场情况和市面上产品的情况分析了摄像机技术的发展趋势，并设计了一款彩色夜视摄像机。

Only person height weeds and the fierce looks stone idles were there.

只有半人深的荒草和龇牙咧嘴的神像。