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941.
Generalized Petersen graphs are commonly used interconnection networks,and wide diameter is an important parameter to measure fault-tolerance and efficiency of parallel pro- cessing computer networks.In this paper,we show that the diameter and 3-wide diameter of generalized Petersen graph P (m,a) are both O( m 2a ),where a ≥ 3.  相似文献   
942.
In this paper we discuss the existence of positive T-periodic solutions for the following second order differential equation
[(x)\ddot]+f(x)[(x)\dot]+g(x)=c(t),\ddot{x}+f(x)\dot{x}+g(x)=c(t),  相似文献   
943.
Irregularities are widespread in large databases and often lead to erroneous conclusions with respect to data mining and statistical analysis. For example, considerable bias is often resulted from many parameter estimation procedures without properly handling significant irregularities. Most data cleaning tools assume one known type of irregularity. This paper proposes a generic Irregularity Enlightenment (IE) framework for dealing with the situation when multiple irregularities are hidden in large volumes of data in general and cross sectional time series in particular. It develops an automatic data mining platform to capture key irregularities and classify them based on their importance in a database. By decomposing time series data into basic components, we propose to optimize a penalized least square loss function to aid the selection of key irregularities in consecutive steps and cluster time series into different groups until an acceptable level of variation reduction is achieved. Finally visualization tools are developed to help analysts interpret and understand the nature of data better and faster before further data modeling and analysis.  相似文献   
944.
In this article, we consider the perturbed classical surplus model. We study the probability that ruin occurs at each instant of claims, the probability that ruin occurs between two consecutive claims occurrences, as well as the distribution of the ruin time that lies in between two consecutive claims. We give some finite expressions depending on derivatives for Laplace transforms, which can allow computation of the probabilities concerning with claim occurrences. Further, we present some insight on the shapes of probability functions involved.  相似文献   
945.
Online dual channel supply chain system and its joint decision on production and pricing under information asymmetry are investigated. First, optimal production and pricing strategies are depicted according to the centralized system. Next, two kinds of contracts are designed for the decentralized system to coordinate the channel system, and their production and pricing decisions are depicted using a principle-agent method for the asymmetric information on the traditional channel. Finally, some interesting insights are found: the centralized system is not always being better than the decentralized system with a feasible contract if the traditional and professional retailer has lower selling cost. When uncertainty in the traditional channel information is higher, the manufacturer prefers a menu of contracts according to different channel settings. When uncertainty is lower, the manufacturer prefers a single contract. Furthermore, the higher the uncertainty in the traditional channel, the more the information welfare of the traditional retailer will gain. Performance with a menu of contracts cannot outperform that with a single contract integrating optimistic and pessimistic market setting well; their difference in performance is bigger when uncertainty in the traditional channel information is less.  相似文献   
946.
Levitin-Polyak well-posedness of variational inequalities   总被引:1,自引:0,他引:1  
In this paper we consider the Levitin-Polyak well-posedness of variational inequalities. We derive a characterization of the Levitin-Polyak well-posedness by considering the size of Levitin-Polyak approximating solution sets of variational inequalities. We also show that the Levitin-Polyak well-posedness of variational inequalities is closely related to the Levitin-Polyak well-posedness of minimization problems and fixed point problems. Finally, we prove that under suitable conditions, the Levitin-Polyak well-posedness of a variational inequality is equivalent to the uniqueness and existence of its solution.  相似文献   
947.
二维相关近红外谱结合NPLS-DA判别掺杂牛奶的研究   总被引:3,自引:1,他引:2  
将二维相关近红外谱与多维偏最小二乘判别分析方法结合起来,建立了掺杂牛奶与纯牛奶的判别模型.分别配置掺杂尿素牛奶(1~20 g/L)和掺杂三聚氰胺牛奶(0.01~3 g/L)样品各40个,采集纯牛奶及掺杂牛奶样品的近红外光谱.在量化二维相关近红外同步谱的基础上,采用多维偏最小二乘判别分析法分别建立了掺杂尿素、掺杂三聚氰胺及两种掺杂牛奶与纯牛奶的判别模型对未知样品进行判别,其判别正确率分别为95%、90%和92.5%,并与偏最小二乘判别和隐变量正交投影判别建模方法进行了比较.结果表明:多维偏最小二乘判别分析法具有更强的预测能力可推广到其它食品的掺杂检测中.  相似文献   
948.
A novel method to photonic generation multiband ultra-wide band (MB-UWB) impulse radio signal based on the summation of multiple doublet pulses with different weights and proper time delays is proposed. Microwave sinusoidal signal is used to amplitude modulate a tunable laser to get multi-wavelength source. The optical signal is then phase modulation with Gaussian pulse and fed into a section of single-mode fiber (SMF). The SMF services as phase modulation to intensity modulation (PM-IM) conversion to generate Gaussian doublet pulse, and offers proper time delays to Gaussian doublet pulses with different weights. MB-UWB pulses with sidelobe suppression levels over 25 dB, central frequency from 5 to 8 GHz, 10 dB bandwidth from 2.9 to 3.8 GHz are obtained in experiment.  相似文献   
949.
ICF靶丸装配误差检测   总被引:1,自引:1,他引:0       下载免费PDF全文
针对激光惯性约束聚变装置中靶丸装配误差检测困难、要求精度高的特点,研制了一套用于微靶装配参数检测的测量系统。提出了一种基于激光与CCD的复合式测量方法,建立了二者数据融合的数学模型,通过标定空间位置关系有效地把二者的测量数据融合到同一个坐标系中,从而实现了高精度三维测量。分两种情况讨论了靶丸装配误差的检测方法。实验结果验证了这两种方法的可行性,并比较了两种方法的测量精度,其极限测量误差均不超过3 m。  相似文献   
950.
赵俊虎*  杨杰  龚志强  支蓉 《物理学报》2013,62(9):99206-099206
本文主要利用实际业务模式的预报结果和丰富的历史资料对乌拉尔山、 贝加尔湖和鄂霍次克海三个阻塞高压活动关键区夏季平均的500 hPa高 度场进行动力-统计跨季度预测实验, 其结果显示该方法能在一定程度上减小模式预报误差, 提高预报技巧, 显示出了良好的业务应用前景. 此外, 敏感性实验显示, 相似指标和相似年选取个数都对预测结果有显著影响. 关键词: 阻塞高压 高度场 动力-统计 跨季度预测  相似文献   
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