驻留时间离差限制参数对三维后装计划的影响分析

目的:研究驻留时间离差限制(DTDC)参数对三维后装计划的影响。方法:选取在中国医科大学附属第一医院治疗的30例妇科肿瘤患者计划,施源器为Fletcher单独宫腔管、全部三管和阴道施源器,每例患者治疗前扫描CT,并由医生勾画靶区和危及器官,以0.1步进修改DTDC参数,由DTDC=0到DTDC=1共制定11个计划,归一至DTDC=0时计划下相应的数值。比较CTV的V_(150)、V_(200),膀胱、直肠的D2cc,驻留时间总和,计划调制指数,分析DTDC参数的修改对三维后装计划的影响。结果:随着DTDC的增加,阴道施源器,Fletcher施源器单独宫腔管和全部三管使用时,CTV的V_(150)和V_(200)分别升高至105%和109%、102%和104%以及115%和120%,直肠和膀胱的D2cc分别至101%和102%、99%和99%以及115%和101%;总驻留时间分别达到DTDC=0时的96%、97%和104%。结论:宫颈癌三维后装计划的制定针对不同的施源器应该选用合适的DTDC参数,给予患者更加合理治疗计划。

限制停时类上最优停时问题（英文）

基于文献[18]的框架,讨论以某种特征的限制停时类为指标集的随机变量族的最优停时问题.运用经典的概率理论,本文证明了最优停时的存在性,刻画了最小、最大停时的特征,给出了相应值函数族的局部性质.当然,上述结论与以往在特殊情况下得出的相一致.

时滞并联限制细胞神经网络的时滞依赖的全局稳定性

通过构造合适的Lyapunov函数,研究了时滞并联限制细胞神经网络的全局稳定性,给出了并联限制细胞神经网络的时滞依赖的全局鲁棒稳定且是全局指数稳定的充分条件。

基于CNDLS的空中多编组时限约束任务分配方法

针对空中多编组任务分配具有整体任务完成时间限制和个体任务完成时窗限制的特点,以最高任务执行效率为目标,建立了包含时限约束的多编组任务分配数学模型。分析编组在作战过程中的资源损耗,构建了编组资源能力动态更新模型,使所建模型更为符合实际作战。在动态列表规划选择任务、量子遗传算法分配编组的基础上,设计了用于求解该模型的循环嵌套动态列表规划(CNDLS)的任务分配方法。针对作战想定进行仿真计算,仿真结果表明所建模型和所提方法能通过多次迭代可实现一定资源和时限约束下的最佳多编组任务分配。

考虑时空间限制的电动汽车充电站布局模型

基于能源需求空间分布的既有新型燃料供应站布局模型解决了需求点与供应站之间的总距离最小、供应站服务客流最大、以及基于此两类目标的多目标优化问题。然而电动汽车充电时间较长的特性对充电站的空间布局问题提出了时间因素的限制。本文提出了充电站空间布局优化应该考虑充电的行为决策问题,即:何时需要充电,去何地充电,以及当因供电站的同时服务容量受到限制而产生排队时作何选择等。在研究充电行为和充电需求的基础上,建立了满足等待时间最短和服务最便利的时空间同时优化布局的动态模型,应用微观仿真方法进行了算例分析,并比较了该模型与传统截流选址模型在算例路网上的应用结果。结果证明时间限制下的行为决策对充电站布局存在较大影响,该动态模型对时间约束的考虑提高了优化结果的有效性。

Synthesis Scheme for Low Power Designs Under Timing Constraints

To minimize the power consumption with resources operating at multiple voltages a time-constrained algorithm is presented.The input to the scheme is an unscheduled data flow graph (DFG),and timing or resource constraints.Partitioning is considered with scheduling in the proposed algorithm as multiple voltage design can lead to an increase in interconnection complexity at layout level.That is,in the proposed algorithm power consumption is first reduced by the scheduling step,and then the partitioning step takes over to decrease the interconnection complexity.The time-constrained algorithm has time complexity of O(n 2),where n is the number of nodes in the DFG.Experiments with a number of DSP benchmarks show that the proposed algorithm achieves the power reduction under timing constraints by an average of 46 5%.

Spatial-Temporal Distribution Characteristics and Limiting Factors of Medium-low Yield Farmland in Tianjin

[Objective] This paper aimed to understand the area change and distribu- tion of medium-low yield farmland, and offered basis to the improvement of mediumlow farmland and its increase of grain production in Tianjin. [Method] Based on the statistical date of Tianjin and its relevant counties and districts, the yield standard was set up to classify high-yield, medium-yield and low-yield farmland in Tianjin. The author analyzed area change of medium-low yield farmland in six agricultural counties and districts （including Jixian County, Wuqing District, Baodi District, Ninghe County, Jinghai County and Dagang district of Binghai New Area） from 1980 to 2010. [Result] The results showed that the average yield of grain rose from 2 445 kg/hm^2 in 1980 to 5 130 kg/hm^2 in 2010, increasing 109.82%. The area of mediumlow yield farmland was reduced from 291 250.13 hm^2 in 1985 to 76 489.87 hm^2 in 2010, coming down 74%. In Tianjin, the area of medium-low yield farmland of 2010 accounted for 19% of the total farmland, of which the ratios of medium-low yield farmland of Jinghai County, Jixian County, Dagang district of Binghai New Area, Wuqing District, Baodi District and Ninghe County were 43.12%, 18.59%, 17.23%, 14.01%, 7.05% and 0, respectively. Low soil nutrient content, drought and water shortage, as well as soil salinization were the main yield limiting factors to mediumlow yield farmland in Tianjin in 2010. [Conclusion] The countermeasures to improve the medium-low yield farmland were proposed, involving enhancing the investment of the government, strengthening the construction of water conservancy infrastructure, further improving the soil fertility, as well as saline and alkaline land, optimizing the farming system and planting drought and salt tolerance crops, etc.

Uniform asymptotics for finite-time ruin probability in some dependent compound risk models with constant interest rate

Consider two dependent renewal risk models with constant interest rate. By using some methods in the risk theory, uniform asymptotics for finite-time ruin probability is derived in a non-compound risk model, where claim sizes are upper tail asymptotically independent random variables with dominatedly varying tails, claim inter-arrival times follow the widely lower orthant dependent structure, and the total amount of premiums is a nonnegative stochastic process. Based on the obtained result, using the method of analysis for the tail probability of random sums, a similar result in a more complex and reasonable compound risk model is also obtained, where individual claim sizes are specialized to be extended negatively dependent and accident inter-arrival times are still widely lower orthant dependent, and both the claim sizes and the claim number have dominatedly varying tails.

分居的日子

5年前的那个黄昏和现在的黄昏没有什么不同。我站在窗前无聊地看着来来往往川流不息的车辆,妻斜倚在桌上不紧不慢地织着毛衣。我俩哑口无言,目光偶尔相撞了,也很快便逃之夭夭,比陌生人还陌生人。

The use of in-situ cosmogenic ^(21)Ne in studies on long-term landscape development

Cosmogenic Ne isotopes are stable and are routinely used for constraining the timing of events and the rate of surface change beyond the limit that can be studied with radionuclides ^10Be, ^26Al, and ^36Cl. Cosmogenic Ne analysis can be used in quartz and in a range of other minerals. Analysis typically requires significantly less material than do cosmogenic ^10Be and ^26Al, opening up the technique for small samples--individual pebbles in fiver sediments, for example. Analysis is easier and faster than for radionuclides, not least because Ne measurements do not require significant chemical procedures. However, the presence of other sources of Ne in minerals tends to restrict the use of cosmogenic ^21Ne to old landscapes and long exposure durations. In this review we briefly outline the background of cosmogenic Ne production in rocks and minerals at the Earth＇s surface, then document the key uses of the technique by highlighting some earlier studies, and finish with a short perspective on the future of the technique.

Adaptive terminal sliding mode control for high-order nonlinear dynamic systems

An adaptive terminal sliding mode control (SMC) technique is proposed to deal with the tracking problem for a class of high-order nonlinear dynamic systems. It is shown that a function augmented sliding hyperplane can be used to develop a new terminal sliding mode for high-order nonlinear systems. A terminal SMC controller based on Lyapunov theory is designed to force the state variables of the closed-loop system to reach and remain on the terminal sliding mode, so that the output tracking error then converges to zero in finite time which can be set arbitrarily. An adaptive mechanism is introduced to estimate the unknown parameters of the upper bounds of system uncertainties. The estimates are then used as controller parameters so that the effects of uncertain dynamics can be eliminated. It is also shown that the stability of the closed-loop system can be guaranteed with the proposed control strategy. The simulation of a numerical example is provided to show the effectiveness of the new method.

Finite-time Control of Fuzzy Discrete-time Nonlinear System with Exogenous Disturbance

This paper give criterions on finite-time control of fuzzy discrete-time nonlinear system subject to exogenous disturbance.Employing the Lyapunov function theory,several suffcient conditions including relaxed ones are presented for finite-time stability via fuzzy controller laws.An illustrative example is given to demonstrate the effectiveness of the proposed method.

Settling Time Design and Parameter Tuning Methods for Finite-Time P-PI Control

High precision position control and high speed control of the robot manipulators are fundamental and important control problems. The effectiveness of finite-time P-PI control was confirmed by end-effector position control of robot manipulators. However, parameter tuning method has not been proposed to finite-time P-PI control. In this paper, we propose a settling time design method and a parameter tuning method for the finite-time P-PI control. The effectiveness of the proposed parameter tuning method is confirmed by experiments of end-effcctor position control of a robot manipulator.

Imitation and Distortion---The Comparison between Three Types of Translation of John Dryden and Translation Theory of Mao dun

During the translation theoretically developments, the discussion on the standards of translation have never been stopped in term of different times, different countries, by different scholars and translators. Some theories share the same or similar superficies and theoretical representation, but they are totally different at a deeper level. However, without restricting from language and culture, time and space, they are interlinked inside. It is interrogative to produce a consolidation with subtle differences of theories. This paper introduces and analyzes the ＇imitation＇ and ＇distortion＇ on the bases of the Three Types of Translation of John Dryden and Translation Theory of Mao dun; by comparing their theory to provide references to the further translation study.

Formation mechanism and modulation of electromagnetically induced transparency-like transmission in side-coupled structures

Based on Fabry model and finite-different time-domain(FDTD) method, the plasmonic structure composed of a metal-insulator-metal(MIM) bus waveguide and a side-coupled resonator was investigated. It is found that the transmission features can be regulated by the cavity width and coupling distance. Electromagnetically induced transparency(EIT)-like transmission can be excited by adding an identical resonator on the pre-existing structure. Combining the foregoing theoretical analysis with coupled mode theory(CMT), the formation process of the EIT-like transmission was detailedly analyzed. EIT-like transmission can also be excited in plasmonic structure with two detuned resonators. By altering the structure parameters, the transparency window can be purposefully modulated. With the merits of compact structure and simplicity in fabrication, the proposed structures may have a broad prospect of applications in highly integrated optical circuits.

放假时妈妈限制我外出，对吗？

起诉案由：每年放寒暑假时，我天天都在家里，妈妈连公园和图书馆也不让我去，可我真的很想出去玩!

Coal combustion restrained by ultra-fine water mist in confined space

In order to apply ultra-fine water mist technology on spontaneous coal combustion in the goaf of a coal mine, we built a small scale compartment with ultra-fine water mist for restraining coal combustion in a confined space and then investigated the restraining efficiency and related factors. The study obtained the following results： a descending rate of heat release, an increase in 02, the production of CO2 decreased gradually, while the production of CO increased dramatically and quickly and then decreased; ultimately it tended to become stable after the discharge of an ultra-fine water mist. The technology showed that the ultra-fine water mist can effectively reduce the heat release rate of coal and the rate to generate components. We found that the restraining effect relied on the mist flux, the discharge time and other factors. A sufficient amount of mist has a better effect compared to an insufficient amount of mist. To combat coal combustion, the greater the discharge time, the better coal flames are extinguished.

Scaling Law of Runaway Electrons in HL-1M Tokamak

Runaway electrons in tokamaks have been widely studied theoretically and experimentally. The runaway confinement time τr in ohmic and additionally heated tokamak plasmas presents an anomalous behavior compared with theoretical predictions based on neoclassical models. A one-dimensional numerical model including generation, acceleration and loss effect of runaway electrons is used to deduce the runaway energy εr dependence on the runaway confinement time.

Differential geometric guidance command with finite time convergence using extended state observer

For improving the performance of differential geometric guidance command(DGGC), a new formation of this guidance law is proposed, which can guarantee the finite time convergence(FTC) of the line of sight(LOS) rate to zero or its neighborhood against maneuvering targets in three-dimensional(3D) space. The extended state observer(ESO) is employed to estimate the target acceleration, which makes the new DGGC more applicable to practical interception scenarios. Finally, the effectiveness of this newly proposed guidance command is demonstrated by the numerical simulation results.