950 resultados para consistency


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The fully consistent relativistic continuum random phase approximation (RCRPA) has been constructed in the momentum representation in the first part of this paper. In this part we describe the numerical details for solving the Bethe-Salpeter equation. The numerical results are checked by the inverse energy weighted sum rules in the isoscalar giant monopole resonance, which are obtained from the constraint relativistic mean field theory and also calculated with the integration of the RCRPA strengths. Good agreement between the misachieved. We study the effects of the self-consistency violation, particularly the currents and Coulomb interaction to various collective multipole excitations. Using the fully consistent RCRPA method, we investigate the properties of isoscalar and isovector collective multipole excitations for some stable and exotic from light to heavy nuclei. The properties of the resonances, such as the centroid energies and strength distributions are compared with the experimental data as well as with results calculated in other models.

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As a recently developed and powerful classification tool, probabilistic neural network was used to distinguish cancer patients from healthy persons according to the levels of nucleosides in human urine. Two datasets (containing 32 and 50 patterns, respectively) were investigated and the total consistency rate obtained was 100% for dataset 1 and 94% for dataset 2. To evaluate the performance of probabilistic neural network, linear discriminant analysis and learning vector quantization network, were also applied to the classification problem. The results showed that the predictive ability of the probabilistic neural network is stronger than the others in this study. Moreover, the recognition rate for dataset 2 can achieve to 100% if combining, these three methods together, which indicated the promising potential of clinical diagnosis by combining different methods. (C) 2002 Elsevier Science B.V. All rights reserved.

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语义Web和Web服务是当前热门的应用技术,而两者的结合——语义Web服务将在未来几年具有极大的应用前景。语义使得~Web~服务的自动发现和自动组装变得非常容易、高效,但是随之而来的问题是如何确保自动组装的~Web~服务组合在本体知识库的状态下是一致的,并且在执行过程中也始终保持一致。 本文介绍了一种基于路径的语义Web服务组合验证方案,通过对服务组合中的单个Web服务进行输入、输出、前置条件和执行效果(IOPE)进行语义标注,旨在找出组合执行过程中在任何结点处可能存在的不一致性。文章定义了显式不一致性和隐式不一致性,首先提出了语义Web服务前置条件和执行效果的正规化表示方法,然后介绍了顺序和并发执行的多个Web服务之执行效果自动化累积算法,接下来给出了基于路径的一致性验证算法。文章还给出了实现该验证方案的平台架构,给出了相关实验过程和结果。 文章还完整地介绍了中科院某研究所本体的构造和扩充过程,定义了研究生毕业申请服务组合,并介绍了服务的IOPE标注,最后运用验证方案对该组合进行验证,给出了验证结果。

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Both commercial and scientific applications often need to transform color images into gray-scale images, e. g., to reduce the publication cost in printing color images or to help color blind people see visual cues of color images. However, conventional color to gray algorithms are not ready for practical applications because they encounter the following problems: 1) Visual cues are not well defined so it is unclear how to preserve important cues in the transformed gray-scale images; 2) some algorithms have extremely high time cost for computation; and 3) some require human-computer interactions to have a reasonable transformation. To solve or at least reduce these problems, we propose a new algorithm based on a probabilistic graphical model with the assumption that the image is defined over a Markov random field. Thus, color to gray procedure can be regarded as a labeling process to preserve the newly well-defined visual cues of a color image in the transformed gray-scale image. Visual cues are measurements that can be extracted from a color image by a perceiver. They indicate the state of some properties of the image that the perceiver is interested in perceiving. Different people may perceive different cues from the same color image and three cues are defined in this paper, namely, color spatial consistency, image structure information, and color channel perception priority. We cast color to gray as a visual cue preservation procedure based on a probabilistic graphical model and optimize the model based on an integral minimization problem. We apply the new algorithm to both natural color images and artificial pictures, and demonstrate that the proposed approach outperforms representative conventional algorithms in terms of effectiveness and efficiency. In addition, it requires no human-computer interactions.

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Self-assembled monolayers(SAMs) of trichlorogermanyl propanoic acid derivatives on hydroxylated silicon substrates are prepared for the first time. Contact angle measurement, ellipsometry and X-ray photoelectron spectrometry(XPS) are used to characterize these SAMs, It is demonstrated that a quasi-2D network is formed on the surface of the substrate after molecules adsorbed on it. The molecular chains have certain tilt angles to the substrate surface, The wettabilities of the SAMs are various,because the molecules adsorbed and liquids used in the experiments are different. It can be concluded that trichlorogermanes have similar self-assembly behavior as trichlorosilanes, Four SAMs are studied together: they are acid, ethyl, butyl and hexyl surfaces whose results are of good consistency.

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The sequences of the ITS (internal transcribed spacer) and 5.8S rDNA of three cultivated strains of Porphyra haitanensis thalli (NB, PT and ST) were amplified, sequenced and analyzed. In addition, the phylogenic relationships of the sequences identified in this study with those of other Porphyra retrieved from GenBank were evaluated. The results are as follows: the sequences of the ITS and 5.8S rDNA were essentially identical among the three strains. The sequences of ITS l were 331 by to 334 bp, while those of the 5.8S rDNA were 158 by and the sequences of ITS2 ranged from 673 by to 681 bp. The sequences of the ITS had a high level of homology (up to 99.5%) with that of P. haitanensis (DQ662228) retrieved from GenBank, but were only approximately 50% homologous with those of other species of Porphyra. The results obtained when a phylogenetic tree was constructed coincided with the results of the homology analysis. These results suggest that the three cultivated strains of P. haitanensis evolved conservatively and that the ITS showed evolutionary consistency. However, the sequences of the ITS and 5.8S rDNA of different Porphyra species showed great variations. Therefore, the relationship of Porphyra interspecies phyletic evolution could be judged, which provides the proof for Porphyra identification study. However, proper classifications of the subspecies and the populations of Porphyra should be determined through the use of other molecular techniques to determine the genetic variability and rational phylogenetic relationships.

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本文主要运用稳定加液-反应系统对海水中方解石和文石形成时稀土元素的共沉淀现象进行了分析,研究了稀土元素在固-液体系中的迁移、转化和分配。进而在对其定量描述的前提下,研究了稀土元素共沉淀对各种反应条件的响应,并对共沉淀行为的机制进行了探讨。 本实验首先运用pH测试、高精度滴定分析等手段测定了实验中的一些基本参数,如[H+]、碱度和[Ca2+],根据计算结果获得了各碳酸体系要素,并以此为基础建立了5℃、15℃和25℃及pCO2=0.003atm下海水中方解石或文石的沉淀动力学方程。实验结果表明: 1)在各条件下,方解石或文石的沉淀速率(R)和其在海水中过饱和度(Ω)存在很好的线性相关性,即海相碳酸盐的沉淀动力学方程可以通过下面的基本表达式来表示:LogR=k*Log(Ω-1)+b ; 2)过高的稀土元素浓度会对文石或方解石的沉淀产生抑制作用,进而对共沉淀过程中YREEs的分异和分馏产生一定的影响。相比方解石而言,文石的沉淀动力学过程承受稀土元素的干扰能力更强; 3)不同温度下得到的方解石或文石各自的沉淀动力学方程存在明显的差异,表明这一过程受热力学因素控制。相对于方解石而言,温度对文石的沉淀动力学的影响更为显著。 与前人研究不同的是,本实验中YREEs的浓度设定在非常低的范围内,从而避免了过高浓度YREEs对方解石或文石沉淀动力学过程的干扰。在最终的反应液中,各种实验条件非常接近自然环境。有关稀土元素的共沉淀行为主要得出以下定性或定量化结论: 1)YREEs在随方解石或文石的共沉淀过程中,均发生了强烈的分异作用。在方解石实验中,稀土元素的分异系数分布曲线呈凸状分布;而在文石实验中,稀土元素的分异系数随原子序数的增加逐渐减小,遵循镧系收缩的规律。总的来说,稀土元素,尤其轻稀土元素在文石中的分异作用要强于方解石。 2)无论是方解石还是文石,沉淀速率对YREEs的分异作用都有着明显的影响。在方解石中,YREEs的分异系数随沉淀速率的增加呈一致性递减趋势;而在文石中,其分异系数对文石沉淀速率有着截然不同的响应:轻稀土元素(La, Ce, Nd, Sm, Eu, Gd)的分异系数随文石沉淀速率的增加而下降,而重稀土元素(Ho, Y, Tm, Yb , Lu)的分异系数则随文石沉淀速率的增加呈上升趋势。 3)在方解石中YREEs的分异系数之间存在非常好的相互关系,表明这些元素是以成比例的方式参与共沉淀。整个谱系呈现中等强度的分馏,MREE相对于LREE和HREE要更为富集;在文石中由于沉淀速率的作用不同,只有Y、Ho、Yb、Lu等元素的分异系数之间有较好的相互关系。YREEs出现了差异性的强烈分馏,在新生成沉淀中轻稀土元素相对于重稀土元素强烈富集。 4)YREEs在溶液中和碳酸盐晶体表面的碳酸根配位形式对YREEs在共沉淀过程中的分异作用极为重要,YREEs在碳酸盐晶体表面的吸附是整个谱系发生分馏效应的关键环节。对于文石来讲,晶体中有效YREE离子和Ca离子半价大小之间的相近程度是其分馏效应的关键因素;而对于方解石来说,YREEs在方解石晶格中的安置就是其分馏效应的关键控制因子,但在晶格安置中起到关键作用的是YREEs和方解石中O原子之间离子键M-O的键长,而非离子半径。 5)综合YREEs在方解石中的分异作用和分馏效应,我们认为M2(CO3)3-CaCO3和MNa(CO3)2-CaCO3是最为可能的两种固体溶液形成模式。 最为重要的是,对比我们的实验结果与前人在灰岩、叠层石、微生物成因碳酸盐等方解石质载体中的研究成果,两者之间出现了非常好的一致性。我们认为方解石质载体将是重建古海水中稀土元素相关信息的重要工具。相比之下,文石质载体不适合作为类似的载体。

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Two marine urostylid ciliates, Holosticha hamulata n. sp. and Holosticha heterofoissneri Hu and Song, 2001, were investigated using live observation and protargol impregnation. Both species were isolated from Korean intertidal sediments of the Yellow Sea. Holosticha hamulata measures about 150 x 25 pro in vivo, and is characterized by a tripartite body shape with a narrow head, an inflated trunk, and a tail that distally projects ventrally forming a hook-like structure. It is the characteristic body shape that distinguishes H. hamulata distinctly from congeners. Holosticha hamulata differs from H. heterofoissneri, possibly the nearest relative, also by the location of the contractile vacuole (ahead of mid-body versus near posterior body third) and the configuration of the macronucleus (on average, 33 scattered nodules assuming a Y-shape versus 17 nodules that may form a U shape). The average number of the macronuclear nodules is a pronounced feature showing great consistency in populations of each species. However, their arrangement is variable in H. heterofoissneri where the nodules are basically scattered or connected by fine fibers forming an elongate U-shape. The location of the contractile vacuole as a taxonomic feature is discussed and a dichotomous key to the species of Holosticha sensu stricto is provided.

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PSD是一种高分辨率、实时性好的光电位置敏感器件,因而具有广泛应用的前景.但在光照度变化条件下,输出信号存在非线性飘移,因而影响了作为位置检测传感器的检测精度,尤其在3D测量时适用性受到了限制.针对这个问题,提出了一种PSD位置传感器的非线性误差补偿方法.该方法针对目标的空间距离变化所产生的PSD输出非线性飘移,采用归一化模型进行误差修正,很大程度上改进了PSD的输出一致性,使基于PSD的3D测量系统性能得以提高.

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论述了基于Internet的力反馈技术及其相关技术的发展和研究意义 ,综合机器人遥操作控制领域的理论方法 ,结合多媒体技术的最新发展 ,构建了一种基于事件的系统结构及其设计方法 .基于该方法 ,分析了系统的可靠性、稳定性及力媒体传输的透明性 ,并设计了一个基于Internet的力反馈技术的系统实例

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为更好地使用锂离子电池组,更精确地估算电池的荷电状态(SOC),对锂离子电池组合前后进行了常温4.0 A充放电、常温7.5 A放电、-20℃下4.0 A放电以及55℃下4.0 A放电等实验测试。实验结果显示:锂离子电池成组后的充放电特性有所下降,电池组总容量下降为单体电池的90%左右,SOC偏低,工作电压的下降速率在放电末期急剧上升,可达平台区的50倍。对电池组的一致性进行了分析,得出锂离子电池成组时应充分考虑单体电池的一致性;在估算SOC时,采用电池组参数和单体电池参数相结合的方式。

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研究移动机器人在动态环境中的导航与避障问题。为提高规划的实时性,提出了基于规则的规划方法,将多移动障碍环境机器人的运动规划分解为相对简单的单移动障碍运动规划,利用最优控制来实现单障碍的最优避障,并用智能搜索方法解决了移动机器人在多移动障碍环境中的实时运动规划问题。仿真实例表明了该方法的有效性。

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文章讲述了交通监控系统中应用视频图像流来跟踪运动目标并对目标进行分类的具体过程和原则.基于目标检测提出了双差分的目标检测算法,目标分类应用到了连续时间限制和最大可能性估计的原则,目标跟踪则结合检测到的运动目标图像和当前模板进行相关匹配.实验结果表明,该过程能够很好地探测和分类目标,去除背景信息的干扰,并能够在运动目标部分被遮挡、外观改变和运动停止等情况下连续地跟踪目标.

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Most of the fields in China are in the middle-late development phase or are mature fields. It becomes more and more difficult to develop the remaining oil/gas. Therefore, it is import to enhance oil/gas recovery in order to maintain the production. Fine scale modeling is a key to improve the recovery. Incorporation of geological, seismic and well log data to 3D earth modeling is essential to build such models. In Ken71 field, well log, cross-well seismic and 3D seismic data are available. A key issue is to build 3D earth model with these multi-scales data for oil field development.In this dissertation, studies on sequential Gaussian-Bayesian simulation have been conducted. Its comparison with cokriging and sequential Gaussian simulation has been performed. The realizations generated by sequential Gaussian-Bayesian simulation have higher vertical resolution than those generated by other methods. Less differences between these realization and true case are observed. With field data, it is proved that incorporating well log, cross-well seismic and 3D seismic into 3D fine scale model is reliable. In addition, the advantages of sequential Gaussian-Bayesian simulation and conditions for input data are demonstrated. In Ken71 field, the impedance difference between sandstone and shale is small. It would be difficult to identify sandstone in the reservoir with traditional impedance inversion. After comparisons of different inversion techniques, stochastic hillclimbing inversion was applied. With this method, shale content inversion is performed using 3D seismic data. Then, the inverted results of shale content and well log data are incorporated into 3D models. This demonstrates a procedure to build fine scale models using multi scale seismic data, especially 3D seismic amplitude volume.The models generated through sequential Gaussian-Bayesian simulation have several advantages including: (1) higher vertical resolution compared with 3D inverted acoustic impedance (AI); (2) consistency of lateral variation as 3D inverted AI; (3) more reliability due to integration cross-well seismic data. It is observed that the precision of the model depends on the 3D inversion.

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Geopolymer gelatinous material was prepared by ferroalloy slag (signed with NKT in laboratory) and circulating fluidization bed slag (CFB slag, signed with NM in laboratory) produced from Heshan city, Guangxi zhuang autonomous region, China. The mechanical properties of the geopolymer made of high content ferroalloy slag can reach the standard of 42.5# portland blastfurnace-slag cement, and it’s processing technology is more simple and not need of mill and burn and will not produce harmful gas. By means of chemical and XRD analyses, it is concluded that NKT is a kind of acidity water-granulated slag with better activation and fit to be activated by alkali activators. Low-cost industrial gypsum (signed with NG in laboratory), analytic reagent oxide(signed with NH in laboratory) and sulfate(signed with NS in laboratory) were selected as alkali activation in the experiment. The results showed NH is a good alkali activator for NKT. Both NH and NG can activate ferroally slag’s activities, but NS can’t alone. The activation effect of superimposing activation of NH and NG excel by separateness. Based on those experiments, optimization compounds were carried out: (1) NKT: NH: NG = 80: 10: 10 and (2) NM: NKT: NS: NG: NH = 10: 70: 2: 8: 10。. The soundness of the test blocks is good by boiling examination. Through XRD, SEM, IR, NMR analyses of geopolymer, the reaction mechanism of geopolymer prepared by alkalescent activating in solid wastes was discussed in the thesis first. It is point out, there is difference in reaction mechanism between traditional geopolymer preparation and the preparation of alkalescent activating solid wastes because NG is a industry product. There is the similar process of depolymerization and reunion of Si-O bond. The latter preparation process generate new subtance but the former doesn’t. In the experiment, we found a performance of NKT that the water requirement of normal consistency of geopolymer reduces with increasing content of NKT. The result shows NKT has some ability to reduce water requirement. The performance is worthy of further research and utilization. Making use of solid wastes to prepare geopolymer, not only can settle environment problem caused by a great deal of dump of NKT, but also settle the shortage of natural resources. Moreover it could take economic, environmental and social benefits and settle thoroughly contradiction in the environment protection and regional economy development and promote circulation economy development.