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1.
研究了在异构计算系统(HCS)中利用表调度式算法进行任务映射与调度.给出两种异构静态优先级表调度式任务映射算法(HSP和GHSP),以及一种异构动态优先级表调度式任务映射算法(BHDP).实验结果表明,GHSP算法对于粗中粒度DAG的调度效果稍好于HSP算法,而BHDP算法对于粗粒度和细粒度DAG的调度效果均明显优于HSP和GHSP算法.  相似文献   

2.
SDH中恢复四次群时钟的数字化预处理方法   总被引:1,自引:0,他引:1  
同步数字系列(SDH)中的指针调整引入了8bit或24bit的大幅度抖动。为了处理这一抖动,提出了一种数字化处理方法——自适应预测法,可以作为预处理方法应用于SDH中的四次群时钟恢复。该方法在一个统计周期内统计指针调整和码速调整的次数,并根据统计结果,在下一个周期内自适应地预测出四次群支路时钟。该时钟不含指针抖动,便于利用模拟锁相环进行最终处理,得到均匀的四次群时钟。从该方法的基本原理,以及对它的静态抖动和抖动转移性能分析中可知,相对于以往的减小指针抖动的方法,如比特泄漏法等,自适应预测法具有输出抖动小,抖动转移性能好,捕捉范围宽等特点。  相似文献   

3.
设(A,H,σ)是斜配对的,文章首先构造了双交叉积A#σH,特别地,Drinfel’d偶D(H)就是这种双交叉积,即D(H)=H^*cop#σH,其中σ为赋值映射。其次,若一般双交叉积Aα#βH有辫子结构σ,则存在σ使得(A,H,σ)是斜配对的,且Aα#βH=A#αH。  相似文献   

4.
为在工程实践中SONET(同步光缆网)和SDH(同步数字系列)设备的有效互通提供理论依据,本文在传输速率、复用结构、映射方式、开销字节等方面对SONET和SDH之间的差异作了比较和研究,结果表明,SONET和SDH虽是不相同的数字传输系列,但两者间是相互兼容可以互通的。  相似文献   

5.
引进了几乎H连续映射的概念,讨论了几乎H连续映射的性质以及几乎H连续映射与连续、H连续、几乎连续、几乎N连续等映射的关系.  相似文献   

6.
作者首先从理论上对准同步数字系列,同步数字系列,同步光纤网作了技术比较,并对SDH和SONET在传输速度,复用结构,映射方式,开销比特等方面作了理论和比较和研究。  相似文献   

7.
本文采用琼脂糖凝胶电泳方法,分析研究了SD大鼠胚胎及成年雌大鼠心、肾和肝组织的乳酸脱氢酶(LDH)同工酶谱和分布。结果表明,大鼠胚胎期LDH同工酶以LDH5含量最高,LDH1含量最低。其同工酶活性顺序为LDH5〉LDH4〉LDH3〉LDH2〉LDH1。而成年雌大鼠心肌以LDH2含量最高,LDH1次之,LDH5最低;其同工酶活性顺序为LDH2〉LDH1〉LDH3〉LDH4〉LDH5;肾组织同工酶活性  相似文献   

8.
研究了Scott Domain上稳定映射的性主Scott Domain上稳定映射与拓扑之间的联系,给出了Scott Domain上稳定映射的特征定理,得到了Sctoo Domain上的稳定映射下Lawson拓扑之间的关系定理。  相似文献   

9.
设B是作用在Hilbert空间H上的含单位元的AFC_代数,D是B的典型masa,S是B中的范数闭算子系统并且是ChordalD_双模,则任给S中正元g,存在完全正映射ψg:B→B(H)使得任给f∈S,ψg(f)=gf,其中fg是g与f的Schur积.  相似文献   

10.
研究了 Scott Dom ain 上稳定映射的性质及 Scott Dom ain 上稳定映射与下拓扑之间的联系,给出了 Scott Dom ain 上稳定映射的特征定理,得到了 Scott Dom ain上的稳定映射与 Law son 拓扑之间的关系定理  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.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

14.
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   

15.
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   

16.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

17.
There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.  相似文献   

18.
In the 19th century the society was controlled by men, and women were just appendants of them, they had not any rights and freedom. But Jane was an exception, she showed some characteristics of early feminist. Jane showed her characteristics of feminism in three aspects: rebellion, equality, and independence. These characteristics were helpful to her success, and feminism is the only way out for women of that time.  相似文献   

19.
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   

20.
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   

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