Modeling and simulation of 2D lithium‐ion solid state battery

The goal of the work presented here was to develop a simulation approach for studying the effects of materials and geometry on the performance of Li‐ion Solid State Batteries (SSB). Simulation provides the opportunity to explore, with ease, different material properties and cell geometries to optimize a Li‐ion SSB's performance. Simulations shown in this paper are time‐dependent and consider electrochemical reaction, heat transfer, the diffusion of Li‐ions and electrons in the electrolyte, and solid Li diffusion in the positive electrode. A 2D model was simulated and the results shown. The simulations were able to show discharge curves, heat flux, the concentration of Li‐ions, electrons, and solid Li at any time in the discharge cycle. Copyright © 2015 John Wiley & Sons, Ltd.     

An SSB encoded by and operating on linear killer plasmids from Kluyveromyces lactis

The Kluyveromyces lactis linear plasmids k1 and k2 belong to the family of protein-primed linear DNA genomes, which includes adenoviruses. Here we identify the 18 kDa gene product of k2ORF5 as a novel putative single-stranded DNA binding protein, SSB. As judged from Western analysis using an epitope-tagged fusion protein and ssDNA-agarose affinity chromatography, the Orf5 protein preferentially binds to ssDNA in vitro. Consistently, electrophoretic mobility shift assays demonstrate that ssDNA plasmid probes from k1 and k2 are retarded by this Orf5-associated SSB activity. ORF5 gene shuffle-mediated mutagenesis in vivo results in k1/k2 plasmid instability, pointing towards a role for the Orf5 protein in plasmid replication. Consistently, the Orf5 protein protects ssDNA from exonuclease digestion and stimulates Klenow enzyme. Our findings suggest a functional role for the Orf5 protein as a putative SSB probably required during k1/k2 plasmid DNA synthesis.     

基于Matlab单边带系统仿真

为了提高相关通信设备课程的理论教学效果,根据单边带信号调制解调的原理及产生方法,采用Matlab软件,利用其集成仿真环境Simulink以及编程分别对单边带调制解调系统进行了仿真,得到了单边带调制解调系统各个环节的理论波形,给出了具有实际应用价值的仿真模型,能实现任意输入信号源的单边带调制解调处理过程。     

基于啁啾光纤布拉格光栅的宽谱光单边带调制方法

提出一种基于啁啾光纤布拉格光栅(CFBG)的宽谱光单边带(OSSB)调制实现方法。光双边带(ODSB)调制信号经过同一CFBG两个相反方向的反射,利用偏振控制器(PC)实现两个方向偏振态的正交。这种双反射CFBG(DR-CFBG)结构可以滤出光载波与其中一个边带实现OSSB调制,同时消除了反射谱内的色散,避免了滤波引起的相位畸变。利用实验制作的线性CFBG搭建了DR-CFBG,实验数据仿真结果表明,本文方法可以实现宽谱基带信号与加载数据信息射频信号的OSSB调制,结果表明传输距离大于6km时,40Gb/s NRZ信号OSSB调制传输有明显优势;加载2.5Gb/s的NRZ信号,OSSB调制传输50km,误码率为10-9时,20GHz射频为载波的功率代价比10GHz低3dB,比40GHz低1.2dB。改进CFBG的边沿斜率可以更好地抑制边带残留,提高OSSB调制信号的传输性能。     

Verification and validation benchmarks

Verification and validation (V&V) are the primary means to assess the accuracy and reliability of computational simulations. V&V methods and procedures have fundamentally improved the credibility of simulations in several high-consequence fields, such as nuclear reactor safety, underground nuclear waste storage, and nuclear weapon safety. Although the terminology is not uniform across engineering disciplines, code verification deals with assessing the reliability of the software coding, and solution verification deals with assessing the numerical accuracy of the solution to a computational model. Validation addresses the physics modeling accuracy of a computational simulation by comparing the computational results with experimental data. Code verification benchmarks and validation benchmarks have been constructed for a number of years in every field of computational simulation. However, no comprehensive guidelines have been proposed for the construction and use of V&V benchmarks. For example, the field of nuclear reactor safety has not focused on code verification benchmarks, but it has placed great emphasis on developing validation benchmarks. Many of these validation benchmarks are closely related to the operations of actual reactors at near-safety-critical conditions, as opposed to being more fundamental-physics benchmarks. This paper presents recommendations for the effective design and use of code verification benchmarks based on manufactured solutions, classical analytical solutions, and highly accurate numerical solutions. In addition, this paper presents recommendations for the design and use of validation benchmarks, highlighting the careful design of building-block experiments, the estimation of experimental measurement uncertainty for both inputs and outputs to the code, validation metrics, and the role of model calibration in validation. It is argued that the understanding of predictive capability of a computational model is built on the level of achievement in V&V activities, how closely related the V&V benchmarks are to the actual application of interest, and the quantification of uncertainties related to the application of interest.     

基于球坐标的非线性小波变换图像压缩编码算法

利用小波变换的3个高频分量之间相关特性,提出了基于球坐标变换的非线性小波变换图像压缩编码的方法,在小波收缩中,采用双曲线收缩处理球坐标下的径向分量以提高重建图像的质量,实验结果表明,此算法在压缩比和重建质量方面都取得较好的效果。     

移相法实现单边带信号的调制

本文单边带（ＳＳＢ）信号的２种产生方法,即滤波法和移相法。重点对移相法的产生ＳＳＢ信号的方法作了祥细的讨论并给出了具体的电路,这种产生ＳＳＢ信号的方法具有载波法抑制比低、低成本、不需要滤波器,对相位误差和增益误差要求不高等突出特点。     

宽带数字单边带下变频器

数字单边带下变频器是软件无线电中不可缺少的组成部分,也是射电观测中,数据采集设备的重要组成部分,由于该模块紧接高速A/D采样器之后,所以对其运算处理能力有很高的要求.本文提出了实现宽带数字单边带下变频器的一种可行方案——并行处理,可以从根本上解决数字信号处理的瓶颈效应.     

A Complexed Crystal Structure of a Single-Stranded DNA-Binding Protein with Quercetin and the Structural Basis of Flavonol Inhibition Specificity

Single-stranded DNA (ssDNA)-binding protein (SSB) plays a crucial role in DNA replication, repair, and recombination as well as replication fork restarts. SSB is essential for cell survival and, thus, is an attractive target for potential antipathogen chemotherapy. Whether naturally occurring products can inhibit SSB remains unknown. In this study, the effect of the flavonols myricetin, quercetin, kaempferol, and galangin on the inhibition of Pseudomonas aeruginosa SSB (PaSSB) was investigated. Furthermore, SSB was identified as a novel quercetin-binding protein. Through an electrophoretic mobility shift analysis, myricetin could inhibit the ssDNA binding activity of PaSSB with an IC₅₀ of 2.8 ± 0.4 μM. The effect of quercetin, kaempferol, and galangin was insignificant. To elucidate the flavonol inhibition specificity, the crystal structure of PaSSB complexed with the non-inhibitor quercetin was solved using the molecular replacement method at a resolution of 2.3 Å (PDB entry 7VUM) and compared with a structure with the inhibitor myricetin (PDB entry 5YUN). Although myricetin and quercetin bound PaSSB at a similar site, their binding poses were different. Compared with myricetin, the aromatic ring of quercetin shifted by a distance of 4.9 Å and an angle of 31° for hydrogen bonding to the side chain of Asn108 in PaSSB. In addition, myricetin occupied and interacted with the ssDNA binding sites Lys7 and Glu80 in PaSSB whereas quercetin did not. This result might explain why myricetin could, but quercetin could not, strongly inhibit PaSSB. This molecular evidence reveals the flavonol inhibition specificity and also extends the interactomes of the natural anticancer products myricetin and quercetin to include the OB-fold protein SSB.     

一种在大功率短波发射机上实用的单边带调制方式

本文介绍了大陆电子公司(CEC)在大功率短波广播发射机上采用的单边带调制方式。文中从低电平单边带信号的形成到采用幅/相分离技术以实现高效单边带信号发射的基本原理和具体做法给出了较详细的分析和说明。