奔腾智能混合动力电动轿车自适应巡航控制系统

为了从整车系统控制角度综合解决车辆的安全、节能和环保问题,突破目前新能源车辆领域和智能汽车领域仍各独自开展相关技术研究的限制,提出一种融合新能源汽车和智能汽车各自先进技术的解决方案—智能混合动力电动轿车,并提出融合双模式切换自适应巡航控制、整车状态识别及转矩分配控制和驱/制动系统协调控制的整车自适应巡航分层控制体系。在上层控制中研究基于实时状态反馈的双模式切换2自由度结构模型匹配控制器,解决适应混合动力驱动系统动态特性的自适应巡航期望转矩制定的难题;在中层控制中采用了综合内燃机(Internal combustion engine,ICE)优化曲线、电动机最佳效率特性和电池最佳效率特性的基线式控制策略;在下层控制中提出发动机/驱动电动机的转矩协调控制策略和电动机制动/EVB液压制动的协调控制策略。在此基础上,通过仿真分析和实车试验对分层控制系统进行评价与验证。仿真与试验结果表明,所开发的分层式控制系统确保整车在自适应巡航状态下,不仅可以有效提高整车安全性和降低驾驶强度,而且使整车具有最佳的燃油经济性和排放性能。     

Production and nutritional aspects of human milk fat substitutes

Human milk fat substitute (HMFS), one of the vital ingredients of infant formula, constitutes about 50% of energy intake for many infants. The composition of HMFS depends on the raw material and the production technology. Both human and animal studies have shown that absorption of fats and minerals are affected by triacylglycerol structures and fatty acid compositions of HMFS. Additionally, the level of other micronutrients, such as fat‐soluble vitamins, can also be affected by production processes. The ultimate goal in the design of infant formula is to mimic human milk, regarding both lipids and other micronutrients. This paper covers human milk fat and selected HMFS as well as their impact on absorption of fat and calcium and illustrates recent progresses and findings.     

铣削加工中工件变形仿真预测方法研究

准确地数值模拟铣削加工过程,对控制工件加工变形、提高加工精度有实际的意义。基于热-机耦合弹塑性有限元方法,采用ABAQUS有限元仿真软件,创建了铣削加工过程的三维有限元模型,预测了工件在铣削力和铣削热耦合作用下的变形情况。研究结果表明,数值模拟计算与实验结果比较吻合,从而证明了该仿真预测方法的可行性与有效性。     

质子交换膜燃料电池催化层设计与优化

催化层作为质子交换膜燃料电池进行电化学反应的重要场所,是膜电极的核心组成部分。叙述了催化层的组成及结构,并评述了近年来人们在催化层设计及优化方面取得的最新研究进展。     

SCR脱硝装置氨消耗量的计算方法探讨

本文结合《GB13323火电厂大气污染物排放标准》中的相关规定,分析了两个公司的《脱硝设计导则》中SCR脱硝装置氨消耗量的计算方法的差异,并提出了一些建议。     

3D reconstruction of histological sections: Application to mammary gland tissue

In this article, we present a novel method for the automatic 3D reconstruction of thick tissue blocks from 2D histological sections. The algorithm completes a high‐content (multiscale, multifeature) imaging system for simultaneous morphological and molecular analysis of thick tissue samples. This computer‐based system integrates image acquisition, annotation, registration, and three‐dimensional reconstruction. We present an experimental validation of this tool using both synthetic and real data. In particular, we present the 3D reconstruction of an entire mouse mammary gland and demonstrate the integration of high‐resolution molecular data. Microsc. Res. Tech. 73:1019–1029, 2010. © 2010 Wiley‐Liss, Inc.     

雷达目标空频域瞬态极化特性及其在几何结构反演中的应用

该文针对高分辨全极化成像雷达体制,研究了雷达目标的空频域瞬态极化特性及其在目标几何结构反演中的应用.给出了空频域瞬态极化特性的表征及获取方法,将已有瞬态极化理论拓广至空频域,并对典型散射结构的空频域瞬态极化特性进行对比分析.作为应用,提出基于空频域瞬态极化特性分析的雷达目标几何结构反演方法,该方法通过揭示空频域瞬态极化特征与散射结构类型间的对应关系,可以克服传统反演的模糊性和局限性,实现更为准确和可信的反演.基于暗室测量数据验证了该方法的有效性.     

Design and implementation of a lightweight online certificate validation service

A PKI (public key infrastructure) provides for a digital certificate that can identify an individual or an organization. However, the existence of a certificate is a necessary but not sufficient evidence for its validity. The PKI needs to provide applications that use certificates with the ability to validate, at the time of usage, that a certificate is still valid (not revoked). One of the two standard protocols to check the revocation status of certificates is the Online Certificate Status Protocol (OCSP). In this article, we propose an OCSP-based implementation that enhances the performance of standard OCSP. In particular, we put special emphasis on those issues that affect security and performance when the validation service is deployed in a real scenario. Finally, we provide experimental results that show that our implementation outperforms standard OCSP.     

Eliminating small stopping sets in irregular low-density parity-check codes

We present a novel scheme to eliminate small stopping sets in irregular low-density parity-check (LDPC) codes. By adding several new check nodes and having their edges connected to small stopping sets in the original code, the improved code decreases the number of small stopping sets efficiently. Simulation results show that the proposed scheme decreases the frame error rate (FER) significantly in the error floor region, whereas having almost the same rate as the original code.     

Electrochemically Tuned Properties for Electrolyte‐Free Carbon Nanotube Sheets

Injecting high electronic charge densities can profoundly change the optical, electrical, and magnetic properties of materials. Such charge injection in bulk materials has traditionally involved either dopant intercalation or the maintained use of a contacting electrolyte. Tunable electrochemical charge injection and charge retention, in which neither volumetric intercalation of ions nor maintained electrolyte contact is needed, are demonstrated for carbon nanotube sheets in the absence of an applied field. The tunability of electrical conductivity and electron field emission in the subsequent material is presented. Application of this material to supercapacitors may extend their charge‐storage times because they can retain charge after the removal of the electrolyte.