求解分段常数图象分割模型的一个快速算法

针对Xue-ChengTai等提出的分段常数图象分割模型,我们提出了一个新的快速求解算法。通过引进一个函数来选择模型中的正则化参数β的值,并判断在迭代过程中何时求解不含惩罚项的泛函F。此函数的引入有效地加速了算法的收敛速度。结合原始-对偶Newton方法来求解总变差最小化问题。数值试验表明新算法具有很快的收敛速度与良好的分割效果,且算法对初始值的要求不高。     

附加类克介质三能级原子系统中光场的相位特性

本文运用 Ｐｅｇｇ－Ｂａｒｎｅｔｔ理论研究类克尔介质腔内相干光场与三能级原子相互作用中相位的演化特性．讨论了类克尔介质的非线性相互作用对相位特性的影响．     

Quantum tunneling dynamics in multidimensional systems: a matching-pursuit description

Rigorous simulations of quantum tunneling dynamics in model systems with up to 20 coupled degrees of freedom are reported. The simulations implement an extension of the recently developed matching-pursuit/split-operator Fourier-transform method to complex-valued coherent-state representations. The resulting method recursively applies the time-evolution operator, as defined by the Trotter expansion to second order accuracy, in dynamically adaptive coherent-state representations generated by an approach that combines the matching-pursuit algorithm with a gradient-based optimization method.     

Architectural Options for the Next-Generation Networking Paradigm: Is Optical Internet the Answer?

Recent advances in optical networking technologies are setting the foundation for the next-generation data-centric networking paradigm, an “Optical Internet”. This work addresses one of the most challenging issues facing today's service providers and data vendors; how will the SONET/SDH-based legacy infrastructure currently in place make a graceful transition to the next generation networking paradigm?

A simplified, two-tiered architecture that requires two types of sub-systems will set the stage for a truly optical internet: service delivery platforms that enforce service policies; and transport platforms that intelligently deliver the necessary bandwidth to these service platforms. If IP can be mapped directly onto the WDM layer, some of the unnecessary network layers can be eliminated, opening up new possibilities for the potential of collapsing today's vertically layered network architecture into a horizontal model where all network elements work as peers to dynamically establish optical paths through the network. This paper presents a balanced view of the vision of the next-generation optical internet

The work presented here builds on the IETF multi-protocol lambda switching (MPλS) initiative and addresses the implementation issues of the path selection component of the traffic-engineering problem in a hybrid IP-centric DWDM-based optical network. An overview of the methodologies and associated algorithms for dynamic lightpath computation is presented. Specifically, we show how the complex problem of real-time provisioning of optical channels can be simplified by using a simple dynamic constraint-based routing and wavelength assignment (RWA) algorithm that compute solutions to three sub-problems: (a) routing; (b) constrained-based shortest-route selection; (c) wavelength assignment.

We present two different schemes for dynamic provisioning of the optical channels. The two schemes use the same dynamic lightpath computation approach proposed here, except that the third component, that is the wavelength assignment algorithm and its implementation, is different for each of the two schemes.

     

介观耦合电路量子涨落与温度的关系

由于电流在电路中运动会产生焦耳热,因而介观电路总是工作在有限的温度下。本文讨论有限温度下介观耦合电路的量子效应,结果表明电荷和电流的量子涨落的温度有关。     

非耗散介观LC电路中电荷和电流的压缩与反压缩效应

利用全量子理论,对非耗散介观LC电路中电荷和电流的压缩与反压缩效应进行了详细的讨论.结果表明:1)通过保持非耗散介观LC电路的固有频率不变,而使电感参量作阶跃函数变化,就可将介观LC电路由初始的真空态经相干态而演化到压缩相干态;并由此进一步分别制备出电荷与电流的压缩最小测不准态;2)通过控制电感参量的改变,可使电荷与电流的量子涨落呈现出压缩与反压缩效应.     

UPLC-MS-MS Method for the Determination of N-(2,6-Dimethoxypyridine-3-yl)-9-methylcarbazole-3-sulfonamide in Rat Plasma and Its Application to a Pharmacokinetic Study

The purpose of the study is first to develop a sensitive and rapid ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS-MS) method for the determination of a new synthesized tubulin ligand, N-(2,6-dimethoxypyridine-3-yl)-9-methylcarbazole-3-sulfonamide (IG-105), in rat plasma. The analyte and internal standard (carbamazepine) were extracted by liquid/liquid extraction with petroleum ether/diethyl ether (2:1, v/v). The chromatographic separation was performed on an Acquity UPLC BEH C₁₈ column with a mobile phase gradient consisting of methanol and water. The mass spectrometric detection was performed by triple-quadrupole mass spectrometry with multiple reaction monitoring (MRM) via an ESI source operating in positive ionization mode. The mass transitions m/z 398??153 and m/z 237??194 were used to assay the analyte and IS, respectively. The method demonstrated good linearity over a concentration range of 0.67?C333.33 ng mL^?1, and the lower limit of quantitation (LLOQ) of IG-105 was 0.67 ng mL^?1. The intra- and inter-day precision (relative standard deviation) values were <6%, and the accuracy (relative error) was <5% at three quality control levels. The extraction recovery of IG-105 and IS was 84.45 and 88.5%, respectively. Finally, the validated method was successfully applied to a pharmacokinetic study of IG-105 in rat plasma.