Effects of awareness program for controlling mosaic disease in Jatropha curcas plantations

The shrinkage of fossil fuel resources motivates many countries to search alternative energy sources. Jatropha curcas is a small drought‐resistant shrub from whose seeds a high grade fuel biodiesel can be produced. It is cultivated in many tropical countries including India. However, the plant is affected by the mosaic virus (Begomovirus) through infected white‐flies (Bemisia tabaci) which causes mosaic disease. Disease control is an important factor to obtain healthy crop but in agricultural practice, farming awareness is equally important. Here, we propose a mathematical model for media campaigns for raising awareness among people to protect this plant in small plots and control disease. In order to archive high crop yield, we consider the awareness campaign to be arranged in impulsive way to make people aware from infected white‐flies to protect Jatropha plants from mosaic virus. The study reveals that the spread of mosaic disease can be contained or even eradicated by the awareness campaigns. To attain an effective eradication, awareness campaign should be implemented at sufficiently short time intervals. Copyright © 2016 John Wiley & Sons, Ltd.     

Simple models for nonpolar solvation: Parameterization and testing

Implicit solvent models are important for many biomolecular simulations. The polarity of aqueous solvent is essential and qualitatively captured by continuum electrostatics methods like Generalized Born (GB). However, GB does not account for the solvent‐induced interactions between exposed hydrophobic sidechains or solute‐solvent dispersion interactions. These “nonpolar” effects are often modeled through surface area (SA) energy terms, which lack realism, create mathematical singularities, and have a many‐body character. We have explored an alternate, Lazaridis–Karplus (LK) gaussian energy density for nonpolar effects and a dispersion (DI) energy term proposed earlier, associated with GB electrostatics. We parameterized several combinations of GB, SA, LK, and DI energy terms, to reproduce 62 small molecule solvation free energies, 387 protein stability changes due to point mutations, and the structures of 8 protein loops. With optimized parameters, the models all gave similar results, with GBLK and GBDILK giving no performance loss compared to GBSA, and mean errors of 1.7 kcal/mol for the stability changes and 2 Å deviations for the loop conformations. The optimized GBLK model gave poor results in MD of the Trpcage mini‐protein, but parameters optimized specifically for MD performed well for Trpcage and three other small proteins. Overall, the LK and DI nonpolar terms are valid alternatives to SA treatments for a range of applications. © 2017 Wiley Periodicals, Inc.     

Simulation of steady-state NMR of coupled systems using Liouville space and computer algebra methods

A series of repeated pulses and delays applied to a spin system generates a steady state. This is relatively easy to calculate for a single spin, but coupled systems present real challenges. We have used Maple, a computer algebra program to calculate one- and two-spin symbolically, and larger systems numerically. The one-spin calculations illustrate and validate the methods and show how the steady-state free precession method converges to continuous wave NMR. For two-spin systems, we have derived a general formula for the creation of double-quantum signals as a function of irradiation strength, coupling constant, and chemical shift difference. The calculations on three-spin and larger systems reproduce and extend previously published results. In this paper, we have shown that the approach works well for systems in literature. However, the formalism is general and can be extended to more complex spin systems and pulses sequences.     

有限元程序自动生成系统及有限元语言

本文介绍了最近发展起来的应用软件的一个新方向——有限元语言和有限元程序自动生成系统。有限元语言是一种比目前的算法语言更高层次的语言。人们采用有限元语言和自动生成系统很容易编写有限元程序,可大大缩短有限元的编程时间,原来需要数月甚至数年才能完成的有限元程序,可望在数天内完成。最后展望了有限元语言对有限元的应用和发展所带来的影响。      

以DSD理论和LS方法为基础的程序燃烧法

给出了二维弯曲爆轰波后产物流场计算方法。爆轰波阵面传播规律满足Detonation Shock Dynamics (DSD)理论并用level set (LS)方法计算,波阵面传播规律与波后流场的耦合通过程序燃烧法实现,反应进程变量可作为LS函数的函数给出。爆轰波从刚性细管道向粗管道传播产生绕射的二维计算结果表明,化学反应速率不影响波后流场分布,只影响反应区结构。此方法可用于钝感炸药的驱动计算问题。     

非导电球型粒子悬浮液宽频介电谱——薄双电层理论的计算机模拟

以Shilov等提出的带有紧密层表面电导率的非导电球型粒子悬浮液宽频介电弛豫的薄双电层理论为基础, 从电动力学角度解释了粒子分散系两种典型介电弛豫(高频和低频弛豫)的机制. 在此基础上, 利用Mathcad程序将该理论定量程序化并建立了粒子/水相分散系介电谱参数与体系内部相参数的关系. 进而利用该程序模拟了溶液浓度、Zeta电位以及分散粒子半径等内相参数对两种弛豫的影响, 结合该理论阐述了不同环境下这两种弛豫的变化规律, 从而为今后更好地利用这两种弛豫表征纳米至毫米级球形粒子分散系的各相电及界面性质提供了有价值的参考.     

混合 0-1 线性规划问题的一个代理约束定界方法

本文给出混合０－１线性规划问题的一个代理约束定界方法,利用代理约束构造一个定界函数,计算量较小,并提出一个分支定界算法,数值计算表明算法是有效的．     

Intelligent Analysis and Off-Line Debugging of VLSI Device Test Programs

Today's microelectronics researchers design VLSI devices to achieve highly differentiated devices, both in performance and functionality. As VLSI devices become more complex, VLSI device testing becomes more costly and time consuming. The increasing test complexity leads to longer device test programs development time as well as more expensive test systems, and debugging test programs is a great burden to the test programs development. On the other hand, there is little formal theory of debugging, and attempts to develop a methodology of debugging are rare. The aim of the investigation in this paper is to create a theory to support analysis and debugging of VLSI device test programs, and then, on the basis of this theory, design and develop an off-line debugging environment, OLDEVDTP, for the creation, analysis, checking, identifying, error location, and correction of the device test programs off-line from the target VLSI test system, to achieve a dramatic cost and time reduction. In the paper, fuzzy comprehensive evaluation techniques are applied to the program analysis and debugging process to reduce restrictions caused by computational complexity. Analysis, design, and implementation of OLDEVDTP are also addressed in the paper.     

Fully RDWB for Electron Impact Excitation of Be-Like Neon

The collision strengths of Be-like neon ion for excitation from ground state 2s²(¹S₀) to nine excited states (principal quantum number n=2) by electron impact are presented.filly relativistic distorted-wave Born (RDWB) program [CHEN Guoxin, Phys. Rev. A53 (1996) 3227] is used for the calculations. Two transitions are compared with other's work. The rest seven transitions are predicted without other ROWB calculations. There are several detailed considerations in our procedures, so the present results should be reliable and accurate.