System-Level Modeling and Simulation of Force-Balance MEMS Accelerometers

This paper presents two approaches for system-level simulation of force-balance accelerometers. The derivation of the system-level model is elaborated and simulation results are obtained from the implementation of those strategies on the fabricated silicon force-balance MEMS accelerometer. The mathematical model presented is implemented in VHDL- AMS and SIMULINK TM,respectively. The simulation results from the two approaches are compared and show a slight difference. Using VHDL-AMS is flexible,reusable,and more accurate. But there is not a mature solver developed for the language and this approach takes more time, while the simulation model can be easily built and quickly evaluated using SIMULINK.

The Research of the Equation Model on the System-level Fault Diagnosis

In this paper we propose an equation model of system-level fault diagnoses, and construct corresponding theory and algorithms. People can turn any PMC model on ex-test into an equivalent equation (or a system of equations), and find all consistent fault patterns based on the equation model. We can also find all fault patterns, in which the fault node numbers are less than or equal to t without supposing t-diagnosable. It is not impossible for all graphic models.

Random testing for system-level functional verification of system-on-chip

In order to deal with the limitations during the register transfer level verification, a new functional verification method based on the random testing for the system-level of system-on-chip is proposed.The validity of this method is proven theoretically.Specifically, testcases are generated according to many approaches of randomization.Moreover, the testbench for the system-level verification according to the proposed method is designed by using advanced modeling language.Therefore, under the circumstances that the testbench generates testcases quickly, the hardware/software co-simulation and co-verification can be implemented and the hardware/software partitioning planning can be evaluated easily.The comparison method is put to use in the evaluation approach of the testing validity.The evaluation result indicates that the efficiency of the partition testing is better than that of the random testing only when one or more subdomains are covered over with the area of errors, although the efficiency of the random testing is generally better than that of the partition testing.The experimental result indicates that this method has a good performance in the functional coverage and the cost of testing and can discover the functional errors as soon as possible.

System-Level EMC Assessment for Military Vehicular Communication Systems Based on a Modified Four-Level Assessment Model

With the development of EMC technology, EMC assessment has become increasingly important in EMC design. Although numerous EMC assessment models are available today, few of them can provide a tradeoff between efficiency and accuracy for the specific case of military vehicular communication systems. Face to this situation, a modified four-level assessment model is proposed in the paper. First, the development of EMC assessment technology is briefly reviewed, and the theoretical mechanism of EMI environment is introduced. Then, the architecture of the proposed model is outlined, and the assessment methods are explored. To demonstrate the application of it, an example involving a communication system in a military vehicle is presented. From the physical layer to the signal layer, a hierarchical assessment on the entire system is successfully performed based on the proposed model, and we can make a qualitative EMC assessment on the EMC performance of the system. Based on a comparison with the traditional model, we conclude that the proposed model is more accurate, more efficient and less time-consuming, which is suitable for the EMC assessment on militaryvehicular communication systems. We hope that the proposed model will serve as a useful reference for system-level EMC assessments for other systems.

Quick System-Level DDR3 Signal Integrity Simulation Research

---Double data rate synchronous dynamic random access memory （DDR3） has become one of the most mainstream applications in current server and computer systems. In order to quickly set up a system-level signal integrity （SI） simulation flow for the DDR3 interface, two system-level SI simulation methodologies, which are board-level S-parameter extraction in the frequency-domain and system-level simulation assumptions in the time domain, are introduced in this paper. By comparing the flow of Speed2000 and PowerSI/Hspice, PowerSI is chosen for the printed circuit board （PCB） board-level S-parameter extraction, while Tektronix oscilloscope （TDS7404） is used for the DDR3 waveform measurement. The lab measurement shows good agreement between simulation and measurement. The study shows that the combination of PowerSI and Hspice is recommended for quick system-level DDR3 SI simulation.

System-Level Performance Evaluation of Very High Complexity Media Applications : A H264/AVC Encoder Case Study

Given the substantially increasing complexity of embedded systems, the use of relatively detailed clock cycle-accurate simulators for the design-space exploration is impractical in the early design stages. Raising the abstraction level is nowadays widely seen as a solution to bridge the gap between the increasing system complexity and the low design productivity. For this, several system-level design tools and methodologies have been introduced to efficiently explore the design space of heterogeneous signal processing systems. In this paper, we demonstrate the effectiveness and the flexibility of the Sesame/Artemis system-level modeling and simulation methodology for efficient peformance evaluation and rapid architectural exploration of the increasing complexity heterogeneous embedded media systems. For this purpose, we have selected a system level design of a very high complexity media application;a H.264/AVC (Advanced Video Codec) video encoder. The encoding performances will be evaluated using system-level simulations targeting multiple heterogeneous multiprocessors platforms.

Advanced System-Level Model Reduction Method for Multi-Converter DC Power Systems

For dynamic stability analysis and instability mechanism understanding of multi-converter medium voltage DC power systems with droop-based double-loop control,an advanced system-level model reduction method is proposed.With this method,mathematical relationships of control parameters(e.g.,current and voltage control parameters)between the system and its equivalent reduced-order model are established.First,open-loop and closed-loop equivalent reduced-order models of current control loop considering dynamic interaction among converters are established.An instability mechanism(e.g.,unreasonable current control parameters)of the system can be revealed intuitively.Theoretical guidance for adjustment of current control parameters can also be given.Then,considering dynamic interaction of current control among converters,open-loop and closed-loop equivalent reduced-order models of voltage control loop are established.Oscillation frequency and damping factor of DC bus voltage in a wide oscillation frequency range(e.g.,10–50 Hz)can be evaluated accurately.More importantly,accuracy of advanced system-level model reduction method is not compromised,even for MVDC power systems with inconsistent control parameters and different number of converters.Finally,experiments in RT-BOX hardware-in-the-loop experimental platform are conducted to validate the advanced system-level model reduction method.

全方位培养自主学习与实践创新能力的教学体系构建与实践

针对高校创新人才培养中存在的问题,如教育教学方法陈旧、实验教学条件有限和学生实践能力不足,缺乏创新意识等,提出并实施“五个环节”研讨式课堂教学方法,打造多层次、虚实结合的实验教学体系,开展“四化”实践教学模式,建立促进学生自主学习与实践创新能力的考核机制等针对性措施,从而全方位提高教育教学质量,培养学生自主学习与实践创新能力,促进新工科人才解决复杂工程问题核心能力的达成。

“枫桥经验”预防性法律制度建设的实践及其成效

宪法、法律在基层社会的实施,高质量的社会规范不可或缺。从多维视角、立足社会治理的“枫桥经验”预防性法律制度建设,既体现问题导向,又服务基层社会治理,追求良法善治的目标,取得了显著成效。“枫桥经验”预防性法律制度主要包括实行综合治理、追求公正效果、健全制度体系、就地化解纠纷,采取预防措施、坚持效果导向、建立预防机制、彰显预防效果,推动制度进步和完善。依法限缩公权力边界,实现基层社会治理方式规范化、治理手段柔性化、治理机制长效化,彰显了基层群众自治制度的优势。

省域国土空间生态修复规划体系构建的逻辑与实践——基于“规划—设计—治理”的视角

国土空间生态修复是推进国土空间治理的重要手段,厘清其规划体系的构建逻辑对于国土空间生态修复规划的编制实施和作用发挥至关重要。从需求层次出发,阐明国土空间生态修复规划体系构建的基本逻辑,以浙江省为例,探索建立省域国土空间生态修复规划体系构建的理论。研究表明:(1)国土空间生态修复规划在需求层面上可体现为“功能修复—韧性提升—价值实现”3个层次。(2)围绕着“整体规划—深化设计—系统治理”的逻辑,提出国土空间生态修复规划作为专项规划的体系构建逻辑。(3)基于构建逻辑,将省域国土空间生态修复规划梳理形成“编制—实施—支撑”3个体系。国土空间生态修复规划要从需求层次变化的认识入手,以维护生态安全、提升空间价值为目标,在省域范围内通过纵向传导、横向深化及全流程支撑3个维度构建规划体系,为系统化开展国土空间生态修复工作探索实施路径。

系统级单粒子效应试验方法研究

为评估星载电子系统抗单粒子效应敏感性及验证系统级加固方法有效性,本文开展了系统级单粒子效应试验方法的相关研究。验证了采用地面模拟装置以逐一辐照系统中器件方式评估系统功能中断率的可行性,提出可通过多种方式获取器件的敏感性数据,指出直接将系统中器件对应的功能中断截面进行加和求取系统截面曲线的不合理之处,本研究为开展系统级单粒子效应试验提供了技术支撑。

基于北斗系统的地表与地下一体式沉降监测新方法

为实现对地质灾害易发区地表沉降与地下沉降的同步、实时、自动监测,研发了基于北斗系统的地质体地表与地下一体化沉降监测新方法。该方法融合了北斗系统、静力水准仪、分层沉降标等沉降监测技术,监测原理如下:在稳定区域设置北斗基准点,在监测区域设置工作基点与监测点;工作基点处的北斗卫星接收机与静力水准仪安装至同一桩上,北斗卫星接收机观测工作基点处静力水准仪的绝对沉降;监测点处的静力水准仪与分层沉降标同轴连接,分层沉降标将深层沉降引至地面由静力水准仪观测;北斗系统与静力水准系统同步采集数据,数据经时间同步后分别得到工作基点和监测点的绝对沉降量。该新方法成功解决了大面积沉降监测中面临的非稳定工作基点校测问题,实现了对地质体地表与地下沉降的远程和实时监测。

一种考虑g敏感性的MIMU系统级标定方法研究

针对微机械惯性测量单元(micro-electro-mechanical-system inertial measurement unit,MIMU)中存在陀螺漂移的g敏感性以及因漂移误差大而无法进行自主方位对准问题,建立了MIMU系统级标定Kalman滤波状态空间模型,考虑g敏感性误差状态的影响,在量测方程中加入方位失准角变化率以增强g敏感性的状态估计可观性;直接采用外输入粗略初始方位角进行导航解算,降低地球自转角速度的影响,提高陀螺漂移估计精度。设计了一套完整的系统级标定转位编排方案,陀螺标定和加速度计标定相互依赖,共同协作完成MIMU系统级标定,能够有效分离出所有30个标定参数,利用某型号弹载MIMU进行了实物标定试验验证,分别用标定前后数据进行导航解算,对比导航结算结果发现标定后的3个方向的导航速度都降低了,加速度计的刻度因数和零偏标定精度更高。特别在MIMU存在多轴大角度转动情况下,近10 min内达到优于30 m/s的导航速度精度,验证了系统级标定具有较高的精度。

灌木平茬机切割系统参数优化设计与验证

为分析圆盘锯式切割系统的切割机理,在Solidworks中建立单组圆盘锯及灌木枝条的简化模型,并在动力学分析软件ABAQUS中进行仿真分析,研究灌木切割过程中工作参数与圆锯片参数的关系。同时,以锯片转速、行进速度、枝径为影响因素,以锯切力为评价指标,对其影响的因素进行虚拟正交试验,并用Design Expert动态响应软件进行分析,得到响应面回归方程,得知当圆锯转速为2500r/min、前进速度为0.9m/s时平茬效果较好。用小型灌木平茬机上进行实地试验,结果表明破茬率和留茬高度均能满足农艺要求。

基于国际比较的我国经济高质量发展水平评估

党的二十届三中全会对进一步全面深化改革推进高质量发展作出了新阐释新部署。依据党的二十届三中全会对推进经济高质量发展内涵的新概括,从新质生产力、数实融合、服务业高质量发展、现代化基础设施建设、产业链供应链韧性和安全5个维度构建了新的我国经济高质量发展水平评价指标体系。针对已有文献主要以国内为参照进行评价的不足,依据我国到2035年人均GDP达到中等发达国家水平的经济现代化发展目标,选取欧盟27国相应指标的平均数为国际参照,利用交叉熵无偏赋权法,对我国经济高质量发展水平进行评估。评估发现:2012—2021年,得益于我国在新质生产力、数实融合、现代化基础设施建设方面取得的长足进步,以及不断增强的产业链供应链韧性和安全水平,我国经济高质量发展水平得到显著提升,2021年达到了67.92%,日益接近欧盟27国的平均水平。但要实现2035年发展规划目标,还需要针对已有的短板和弱项,进一步加快推进创新发展、绿色发展和人才强国建设。

基层中医药适宜技术遴选指标体系的构建

目的:构建基层中医药适宜技术评价遴选指标体系。方法:对山东、四川等11个代表性省份进行调研和文献研究,收集、汇总已有的基层中医药适宜技术相关遴选指标体系;组织权威专家对既往基层中医药适宜技术相关遴选指标体系遴选维度和遴选指标进行合并、增删等操作,初步得出基层中医药适宜技术相关遴选指标体系;组织专家开展初步遴选,收集专家对遴选指标体系的意见;组织15个省(区、市)开展正式遴选,收集各省份对遴选指标体系的建议。结果:从安全性、有效性、规范性、经济性、推广性5个维度构建了基层中医药适宜技术遴选指标体系,该遴选指标体系包括5个一级指标,12个二级指标和54个三级指标,且实现了量化评分。结论:本研究建立的基层中医药适宜技术遴选指标体系具有科学、系统和可操作性强等特点,可为基层中医药适宜技术的遴选提供参考工具。

明代府州县的繁简与等级划分——以江西为中心的考察

从秦汉到元朝,皆以户口数量为主要指标,兼顾政治地位、地理位置、经济水平等因素,把地方政区划分为若干等级。明太祖一改前代做法,先是以税粮为标准把府州县分为上中下三等,旋即又综合考虑税粮多少以及地理冲僻、事务繁简、负担轻重等因素把府州县分为繁简两等,开启了主要依照事务繁简和地理冲僻等因素划分政区等第的新趋向。到明代后期,繁简两分法被进一步发展为上中下三等制。从江西各府州县的相关资料看,上、中、下等级与政务繁简、道里冲僻、治理难易等因素之间具有一定的对应关系,但这种对应并不严格,说明政区等级评定是个非常复杂的问题,无论采用何种标准都难全部适用。

颗粒阻尼在浮筏隔振系统中的减振特性研究

在船载和舰载机械设备的隔振工程实践中,浮筏系统作为一种高效被动振动控制措施得到广泛应用。为进一步提高浮筏隔振系统的减振效果,以一低内阻浮筏隔振系统为研究对象,采用子结构导纳法建立其动力学方程。设计由厚壁铝壳和不同粒径钢珠构成的颗粒阻尼器,将其安装于浮筏隔振系统的上平台或下平台。使用激振器对浮筏隔振系统进行扫频激励,通过对比安装有等质量的颗粒阻尼器和配重的隔振系统振级落差,定义颗粒阻尼器的替代损失和平均替代损失,通过该指标研究颗粒阻尼安装位置、粒径、填充率、表面粗糙度等对隔振性能的影响,并对颗粒阻尼器减振效果进行评估。研究表明,在浮筏隔振系统中颗粒阻尼器在较宽频段上都能起到良好减振效果,颗粒阻尼器平均替代损失大约能够达到4dB。

基于排水系统主动降水位的污涝同治方案设计

合流制排水系统具有投资少、工期短、见效快等优点,但也容易导致污水管网高水位运行,反噬下游地区排水系统安全,导致旱季污水溢流入河污染水环境,雨季内涝积水影响水安全。通过研究污水泵站进水管水位变化,查明了D片区污涝矛盾突出的原因。采取熔断措施构建独立排水区域后,排水管网水位降低1.6 m以上,开闸次数由83次/年降低到17次/年,COD入河量减少248.4 t/年,氨氮19.7 t/年,保障河道水质达到Ⅴ类。

夸美纽斯终身教育制度构想的当代影响及审思

夸美纽斯在他的《大教学论》和晚年出版的《人类改进通论·泛教论》中分两步完成的七级学制构想,为近现代学校教育提供了制度范本,也成为了之后发展现代终身教育的制度建设仿本。其所体现的合成式的“机械整体性”所招致的看不见的问题,将人们引入了“各阶段教育的加和就是终身教育”的认知误区中,深度制约着终身教育的突破与创新,使面向青少年的学校教育固化成为单一的主流模式以及其他各类教育地位不平等的问题至今难以解决。夸美纽斯终身教育制度构想的影响是多方面的,我们需要在理论突破与认知迭代中不断澄清理论误区,即突破机械整体性思维定势的制约,以生命整体性思维观反思当今的教育变革之路,推动我国终身教育的实质性发展。