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1.
本文介绍了TVGA扩充图形模式SUPERVGA256色的编程技术,并给出了这些模式下的读写象素方法。  相似文献   

2.
基于双正交小波的快速矢量量化算法   总被引:6,自引:0,他引:6  
提出了一种用于图象压缩的矢量量化算法.该算法通过构造符合图象小波变换系数特征的跨频带矢量,利用小波系数之间的相关性,提高了图象的编码效率和重构质量.同时,该算法又采用了两种新的矢量量化技术——非线性插补矢量量化(NLIVQ)和渐进构造聚类(PCC),提高了矢量量化的速度和码书质量.实验结果证明,该算法在比特率为0.172bpp的条件下仍能获得PSNR>34dB的高质量重构图象.研究图象小波变换系数的固有特性是提高矢量量化性能的关键,而提高矢量量化速度是这类算法得以实用的重要前提.  相似文献   

3.
研究了4-(8-氨基喹啉-5-偶氮)-苯横酸钠(SAOABS)的极谱行为。在0.02ml/LNH_3·H_2O-0.36mol/LNH_4Cl的缓冲溶液中,SAQABS产生两个明晰的阴极化极谱波,其二次导数波的峰电位分别为-0.52V和-1.30V(Vs.SCE)。用SAQABS的第一个波作为定量分析的基础,其线性范围为1.0×10 ̄(-6)~8.0×10 ̄(-5)mol/L。氧不干扰SAQABS的测定。还研究了SAQABS的电极过程及反应机理。  相似文献   

4.
提出了一种基于FPGA的具有计算机接口的灵活的图像采集系统.在FPGA模型中集成了采集计数器、时钟控制、DMA信号发生器和I/O接口逻辑等功能模块,相当于40多个74LS系列芯片.由于现场可编程逻辑阵列的灵活性,系统可以很方便地实现CIF,QCIF,256×256和128×128等多种图像格式的采集.  相似文献   

5.
PMSQ/PVC(100/0,70/30,50/50,30/70,0/100)共混物由溶液浇法制备.经透射电镜观察到该共混物呈微观分相,但两相间界面较模糊;当PVC含量增至70%时,发生相逆转.所有共混物的扭辫曲线均只有唯一的玻璃化转变,并且由扭辫技术测得的PMSQ/PC共混物的Tg与由经验公式计算值相吻合,PMSQ、PVC在TBA测试尺度上的相容性较好.由于PMSQ中的SiOH在第一次升温中当温度高于318K时发生进一步交联反应,所有共混物二次加热后的Tg均比第一次升温时高,热历史对PMSQ/PVC共混物的Tg影响较大  相似文献   

6.
催化剂活性区域分布的计算机图象纹理小波分析   总被引:2,自引:1,他引:2  
利用计算机图象纹理分析方法研究了钒催化剂表面活性微区分布及特征,计算了催化剂表面的SEM图象对象素的奇异强度值.结果表明奇异强度值在3.0~4.0范围内为催化剂表面活性区域,活性催化剂占活性区域整个表面积的15%~18%,而非活性催化剂仅占1.8%.  相似文献   

7.
针对传输凝固图象的要求,提出了一种压缩编码方案。方案具有压缩比高,抗干扰能力强,算法简单,易于硬件实现等特点。用它对多幅256×256个象素,每象素8bits 的图象进行了计算机模拟实验。实验结果最高可达31.65 dB(1bit/pixel),恢复的图象主客观效果良好。  相似文献   

8.
设R是有单位元的环,S是R的Excellent扩张,G是有限群且|G| ̄(-1)∈R.证明了R是右余半遗传环(QF-3环,GV-环)当且仅当S是右余半遗传环(QF-3环,GV-环),也当且仅当Smach积R#G是右余半遗传环(QF-3环,GV-环).  相似文献   

9.
非微扰(短距离) 量子场论的横动量标度分布Q- v⊥ Kν(β⊥ Q⊥/〈Q⊥〉) 与实验数据( S= 5 ~1 800GeV)符合得很好,在固定多重数N 用快度截断技术后的质量证认数据( 单个强子源, S= 1 800 GeV) 与低能p⊥- 分布重合( S= 5GeV) ,低能p⊥- 分布反常的困难消失.这里量子场反常维度-2 γB( gR) = 0 .084±0 .002 (αs = 0 .126 ±0.003 ,QCD).强子源的相对论性多普勒(Doppler)效应存在,而标度律仍然成立.  相似文献   

10.
非微扰(短距离)量子场论的横动量标度分布Q^-⊥^vKv(β⊥Q⊥/〈Q⊥〉)与实验数据(√S-5~1800GeV)符合复活很好,在固定多重数N用快度截断技术后的质量证认数据(单个强子源,√S=1800GeV)与低能p⊥-分布重合(√S=5GeV),低能p⊥-分布反常的困难消失。这里量子场反常维度-2γB(gR)=0.084±0.002(α2=0.126±0.003,QCD)。强子源的相对论性多普  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

13.
王慧 《科技信息》2008,(10):240-240
Wuthering Heights, Emily Bronte's only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.  相似文献   

14.
The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.  相似文献   

15.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

16.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

17.
Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.  相似文献   

18.
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-  相似文献   

19.
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-  相似文献   

20.
正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that  相似文献   

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