Robust numerical approach to steady-state calibration of mean-value models

A numerically robust approach to steady-state calibration of nonlinear dynamic models is presented. The approach is based on explicit formulation of the constraints on validity of internal model signals by set of inequalities. The constrained optimization with feasible iterates guarantees that the model will never be evaluated with invalid internal signals. This overcomes numerical difficulties often encountered when dealing with highly nonlinear models. Because the approach uses a large number of slack variables, distributed least squares algorithm is proposed. The robustness of this approach is demonstrated on a steady-state calibration of turbocharged diesel engine model starting from grossly inaccurate initial estimates.     

不同品种烤烟成熟期糖代谢酶活性及基因的表达分析

为了探究不同品种烤烟成熟期糖代谢的变化规律,明确烟叶品质形成的分子作用机理。以烤烟品种秦烟96、豫烟6号和K326为试验材料,测定分析了烤烟成熟期水溶性糖组分（葡萄糖、果糖、麦芽糖、蔗糖、还原糖和可溶性总糖）含量、糖代谢关键酶活性及基因表达的变化。结果表明,3个品种烤烟水溶性糖组份含量变化趋势基本一致,各水溶性糖（蔗糖除外）含量呈先升高后降低的变化趋势,烟叶成熟时其含量达到峰值;蔗糖含量呈双峰波动,烟叶成熟时蔗糖含量较低。烟叶打顶至适熟阶段,SPS和AI酶活性对烟叶中水溶性糖的积累贡献最大,NtINV对烟叶糖代谢起主要调控作用;当烟叶由适熟至过熟时,AI酶活性主要参与烟叶糖代谢活动,而SS和SPS则对蔗糖积累起重要作用,NtSS和NtSPS对烟叶糖代谢起主要调控作用。同一生态环境和栽培条件下,豫烟6号内含物质充实,具有较高的水溶性糖分含量,SPS和AI酶活性的差异可能是造成烟叶糖组分及含量不同的重要原因。     

Low-cost teleoperable robotic arm

A low-cost robotic arm and controller system is presented. The controller is a desktop model of the robotic arm with the same degrees of freedom whose joints are equipped with sensors. Manipulating the controller by hand causes the robotic arm to mimic the movement in master–slave fashion. This is accomplished simply and at low-cost by taking advantage of widely available hobby radio control components. The system uses the trainer (“Buddy Box”) function available on common radio control transmitters as a simple interface between microcontroller and transmitter. The microcontroller produces a time-division multiplexed signal comprising three channels in proportional pulse modulated (PPM) format. The arm design could be used for various light-duty applications and this paper describes a version fitted with a video camera. The arm prototype is designed for an under-vehicle inspection robot. In this application, the video camera mounted on the robotic arm allows inspection of difficult-to-view locations under vehicles. The master–slave operator interface provides an easy-to-learn method for robotic arm manipulation.     

Ion-implantation modification of lithium–phosphorus oxynitride thin-films

Among various solid electrolytes, the lithium–phosphorus oxynitride (Lipon) electrolyte synthesized by sputtering of Li₃PO₄ in pure N₂ has a good ionic conductivity of 2(±1)×10⁻⁶ S cm⁻¹ at 25° C. As the nitrogen concentration increases in the Lipon electrolyte, the ionic conductivity is reported to increase as a result of a higher degree of cross-links. When Lipon films are deposited by sputtering, however, it is reported that the maximum nitrogen concentration saturates approximately at 6 at.%. By non-equilibrium processes, such as ion-implantation, nitrogen concentration can be controlled over 6 at.%. This study investigates the effect of nitrogen concentration on the ionic conductivity in Lipon films by using ion-implantation. Impedance measurements at 25° C show that the nitrogen-implanted Lipon films enhance or retard the ionic conductivity over a wide range after nitrogen-implantation, when compared with as-deposited thin-films.     

中花6号花生仁压缩力学性能及仿真分析

目的 研究3种成熟度花生仁在3种压缩方向下的力学性能。方法 以中花6号花生仁为研究对象,通过正压、侧压和立压等3种方向,对3种不同成熟度样品进行压缩试验,获得力学特性曲线,计算其弹性模量和抗压强度等力学参数;通过方差分析得出成熟度、压缩方向与各力学参数之间的关系;通过三维建模和有限元分析,比较试验值与模拟值之间的误差,验证花生仁压缩试验及有限元分析的可靠性及准确性。结果 在3种压缩方式下,测得3种不同成熟度的花生仁弹性模量为15.33~45.66 MPa,破裂力为45.5~153.4 N,弹性变形量为0.72~2.22 mm,抗压强度为16.25~47.94 MPa。成熟度对花生仁抗压强度和破裂力的影响极显著(P<0.01),对花生仁弹性模量和弹性形变的影响显著(0.01<P<0.05);压缩方向对花生仁弹性模量和弹性形变的影响显著(0.01<P<0.05),对花生仁抗压强度和破裂力的影响不显著(P>0.05)。结论 相同成熟度的花生仁,在立压方向下最容易发生破裂;花生仁属于各向异性材料,种脐部位为花生仁受力最薄弱的位置。     

脂质体外消化过程中氧化评价模型与检测方法研究进展

脂质是人体所需三大营养素之一,其全摄入链的安全和健康特性备受重视。胃肠道内含有羟基、活性氮族等多种促氧化因子,使脂质在胃肠道消化过程中易产生氧化反应。体外模拟消化相比体内消化评价具有耗时短、无伦理问题等优点,是研究脂质胃肠道消化的优选方法。同时,考虑到人体消化道环境的复杂性和脂质的多样性,消化后脂质氧化状态的真实评价也尤为关键。在研究脂质消化过程以及脂质在消化道中的氧化状态时,需要将这些方法整合利用以求对相关问题进行全面性的探索。作者介绍了脂质在体内的消化过程和目前研究脂质常用的体外消化模型,阐述了脂质消化过程中氧化产物的检测方法,对于系统研究特定脂质消化过程中的氧化机理、氧化途径具有重要意义。     

建筑胶粘剂多功能分散机的研制及应用

实践证明性能优异的多功能分散机能有效地将各种极细粒径的粉状填料均匀的分散于结构胶的胶液中,使添加超细粒径填料的产品的技术性能有明显的提高,产品的质量也更加稳定,能生产出达到国家标准的结构胶产品。本文介绍了一种多功能分散机的设计思路、构造、特点、性能等。     

后续换相失败引发的换流变零序差动保护误动场景分析及策略

发生后续换相失败后直流接地极入地电流经地网耦合与大直流共同入侵换流变压器中性线,分析了该工况下换流变压器中性线零序电流的特征及其对换流变中性线零序电流互感器传变特性的影响,并探讨了该工况下换流变零序差动保护的误动风险.利用细化的快速傅里叶变换对零序差动电流的幅频特征进行细分,将零序差动电流在低频频带与工频频带的幅值之比作为辅助判据,识别所讨论的工况,闭锁零序差动保护.仿真结果表明,所提策略能有效防止所讨论的工况引发的换流变零序差动保护误动作.     

面向固定条盒自动装填设备协同设计的任务规划研究

目的 解决固定条盒自动装填设备的复杂机械设计中，多人协同设计的作业效率问题。方法 采用基于模糊设计结构矩阵(FDSM)的任务规划方法进行任务规划，根据机械设计关联尺度将整体设计任务进行分解，将各设计任务间的耦合关系度量化并构建模糊设计结构矩阵，经过行列变换和分区算法解耦，得出规划后的协同设计任务顺序和分配。结果 通过G–value值验证，优化前后矩阵紧密性程度降低了24.95%了，有效降低了多人协同的相互制约。结论 基于模糊设计结构矩阵(FDSM)的任务规划方法能有效提高固定条盒自动装填设备多人协同设计的工作效率。