电动汽车用电池智能化快速充电研究

基于电池快速充电基本原理,制定了电动汽车用电池的分段恒流充电方案.根据对分段恒流充电试验结果的分析,对其控制策略进行了调整:按容量梯度法确定分段恒流充电终止控制参数,适当减小各段恒流值下降梯度,并将电池温度设为充电安全保障控制参数.调整方案后的充电试验结果表明,这种分段恒流充电控制方法可实现动力电池的智能化快速充电,有效缩短充电时间、提高充电效率.     

基于等压差时间差的镍镉电池快速超快速充电算法

为安全、高效地实现镍镉(Ni-Cd)电池快速超快速充电,提出一种基于等压差时间差的Ni-Cd电池快速超快速充电算法。算法依据Ni-Cd电池充电电压特性和温度特性确定大倍率快速超快速充电脉冲波形,通过大倍率放电时端电压来判断电池剩余容量状态等级,根据Ni-Cd电池充电等压差时间差特性实现满充判据。该算法易于实现,能够在不降低电池容量效率和循环寿命条件下实施安全、快速充电。     

基于单片机控制的智能充电器

本文设计了一种针对镍镉电池的智能恒流充电器,具有结构简单、充电快速的特点,采用恒流充电的方式,对电池进行充电,有电压检测功能,转换电路由MOSFET功率开关来控制电流大小的切换,实现充满后自动转为涓流充电且报警提醒,保护电池寿命。在电路中用AT89C2051单片机来实现控制作用,从软硬件两个方面来共同实现,且整个充电过程可由单片机控制的指示灯看到。     

智能锂电池充电器设计

为解决锂电池的快速充电问题,设计一种具有电压和电流检测功能的智能锂电池充电器系统,并给出了相关单元模块电路及其驱动程序的流程图。该设计以MSP430单片机为控制核心, 对电池进行电压电流采集,通过判断电池所处的充电状态,调整PWM （Pulse Width Modulation)波的占空比,以实现高精度控制充电。实验结果表明,该智能充电器可安全地进行锂电池的快速充电,耗时约1 h,比一般充电器(2~3 h)的充电速度有显著提高,从而有效缩短了锂电池的充电时间。     

电容降压脉冲式电动自行车快速充电器设计研究

电动自行车以灵活方便,经济实用的特点成为现代普通家庭的主要代步工具。但其续行能力差,电池易被充坏,充电慢的缺点为人们所诟病。该文介绍了一种基于电容降压,以PIC系列单片机为控制核心的放电式脉冲快速充电的方式。该方式不但充电速度快,普通家用电动自行车最多在2 h内充满,充电过程不会损伤电池,而且有修复电池的功能。     

基于智能控制的锂电池快速充电方法研究

针对电动汽车不能实现快速的电能补充以及电池充电过程中存在的非线性、时变性和不确定性导致充电过程不稳定的问题。本文设计了一种基于模糊自适应PID控制的快速充电方法,在充电过程中引入了电压降补偿,并分别对锂电池充电系统的电流内环和电压外环进行控制,使实际充电曲线更加接近马斯曲线。理论分析和仿真实验表明,该充电方法加快了蓄电池充电速度,且具有稳定性好等优点。     

镍氢电容电池快速充电系统

为实现以镍氢电容电池为动力系统的电动大巴车的快速充电设计了快速充电系统.通过Matlab/Simulink对网侧谐波含量进行电气仿真,并根据镍氢电容电池的短时大电流充电特性,选取电压控制法作为充电终止参数,实现电动大巴车的快速充电.     

基于模糊自适应PID算法的改进三段式蓄电池快速充电系统

该文针对现有蓄电池充电速度较慢、易出现过充且充电效率不高的缺陷,提出了一种基于模糊自适应PID算法的改进三段式蓄电池快速充电方法。使用上述算法对充电系统进行相应控制,以达到快速充电、防止过充现象发生的效果。对该系统的Matlab/Simulink仿真结果表明:该方法能够有效地提高充电效率,延长电池寿命。     

大功率智能充电机

北京交通大学电气工程学院智能控制实验室长期从事电动汽车领域的研究．针对电动汽车充电要求快速、可靠，充电过程复杂等特点，开发出系列大功率电动汽车用充电机．在高频大功率开关电源的基础上，加入一套完善的控制系统和保护机制，能够使电池的充电过程最优化和多样化．目前，已经形成产品的有10kW、30kW、50kW三种类型的充电机．     

锂离子电池智能充电控制器的研究与设计

该文论述了一种先进的锂离子电池充电控制器设计：在充电前检测电池的电压值,再对电压过低的电池进行涓流充电。当电池最终浮充电压达到4.2 V时,充电过程终止,整个过程由低功耗MCU进行控制。在检测到温度升高时,内部的热限制电路将自动减小充电电流。再结合专用的控制执行和保护电路,实现了锂离子电池充电控制的智能化。该设计通过了理论分析与实物制作测试,证明了该设计可行、可靠。     

Markedness and its Interpretation in Language Use

Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.     

Lower Paleozoic oil relationships within Williston Basin, Canada

The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.     

An Analysis of Catherine＇s Character——Wuthering Heights

Wuthering Heights, Emily Bronte＇s only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.     

Characterization of Ordovician carbonate reservoirs, southeastern Saskatchewan, Canada

The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3～4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰～ -7.8‰, PDB) and matrix dolomites (-6.6‰～ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084～0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078～0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.     

Features of Women's language

Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women＇s language from these perspectives： pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women＇s language, more attention should be paid to language use in social context. What＇s more, the linguistic phenomena in a speaking community can be understood more thoroughly.     

Design and analysis of generic LBS application developing platform

Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.     

橡胶颗粒沥青混合料低温抗裂性试验研究

以AC-13级配为基础,将橡胶颗粒代替部分集料掺入混合料中,以低温弯曲试验为评价方法对不同橡胶颗粒掺量下沥青混合料的低温抗裂性进行研究,并引入应变能密度值对混合料的低温抗裂性进行综合评价.试验结果表明:橡胶颗粒沥青混合料试件的破坏微应变均超过2 300,满足冬寒区的技术指标;无论是否掺加橡胶颗粒,随着温度的下降,沥青混合料破坏时的最大弯拉强度增大,弯拉应变降低,劲度模量增大;弯曲应变能密度在胶粒掺量为1%左右时具有较大的弯曲应变能密度值,此时橡胶颗粒沥青混合料具有较好的低温抗裂性.     

A computer generator for randomly layered structures

AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…     

低渗透非均质砂岩油藏启动压力梯度研究

理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。     

Quantitative trait loci （QTLs） for quality traits related to protein and starch in wheat

Quality traits in wheat （Triticum aestirum L.） were studied by quantitative trait locus （QTL） analysis in a recombinant inbred line （RIL） population, a set of 131 lines derived from Chuan 35050 × Shannong 483 cross （ChSh）. Grains from RILs were assayed for 21 quality traits related to protein and starch. A total of 35 putative QTLs for 19 traits with a single QTL explaining 7.99-40.52% of phenotypic variations were detected on 10 chromosomes, 1D, 2A, 2D, 3B, 3D, 5A, 6A, 6B, 6D, and 7B. The additive effects of 30 QTLs were positive, contributed by Chuan 35050, the remaining 5 QTLs were negative with the additive effect contributed by Shannong 483. For protein traits, 15 QTLs were obtained and most of them were located on chromosomes 1 D, 3B and 6D, while 20 QTLs for starch traits were detected and most of them were located on chromosomes 3D, 6B and 7B. Only 7 QTLs for protein and starch traits were co-located in three regions on chromosomes 1D, 2A and 2D. These protein and starch trait QTLs showed a distinct distribution pattern in certain regions and chromosomes. Twenty-two QTLs were clustered in 6 regions of 5 chromosomes. Two QTL clusters for protein traits were located on chromosomes 1D and 3B, respectively, three clusters for starch traits on chromosomes 3D, 6B and 7B, and one cluster including protein and starch traits on chromosome 1D.