PC机和单片机之间文件传输

讨论了利用微处理器对FPGA进行在线配置时配置文件的传输问题。给出了实现通信传输的硬件接口电路以及相应的软件程序。其中PC机采用Visual C＋＋6．0编程环境进行设计，利用串行通信控件MSCOMM，实现了PC与单片机间快速、准确、可靠的文件传输。     

Rollover detection and control on the non-driven axles of trucks based on pulsed braking excitation

The major challenges for rollover detection are the accurate modelling of vehicle dynamics and the real-time estimation of the varied parameters. To circumvent the dependence on vehicle parameters, a novel rollover detection method based on the pulsed braking excitation is proposed. With the lateral load transfer ratio (LTR), the relationship between rollover risks and non-driven wheel rotational dynamics is deduced, which is the basis to apply braking excitation on wheels. The lateral acceleration is adopted as the first criterion to activate the rollover detection. Once the pulsed braking is applied to the non-driven wheels, the braking pressure and wheel angular speeds are measured to estimate the LTR on the non-driven axle. In case of emergency, the differential braking-based anti-rollover is implemented. Experiments were conducted on a Hardware-in-Loop bench. The results show that, the pulsed braking can be activated timely, and the LTR on the non-driven axle is estimated accurately. With the anti-rollover control, the roll stability is improved considerably.     

十堰市承接东部地区产业转移的思考

分析了十堰市承接东部产业转移的各项条件和优势,提出了以优势产业为基础培育支柱产业、利用资源优势发展产业集群,培植壮大新兴配套产业、发展工业园区经济和加快创新体系建设的建议。     

9 000 hp拖船总振动的计算与试验研究

简要介绍了9000hp拖船总体振动的计算方法,并采用锚激发对船体的总振动进行试验研究。试验结果表明利用迁移矩阵法计算得到的压载出港条件下全船的振动结果与试验结果差距不大。     

File Transfer Algorithm for Autonomous Decentralized System

A file transfer algorithm based on ADP (autonomous decentralized protocol) was proposed to solve the problem that the ADS (autonomous decentralized system) middleware (NeXUS/Dlink) lacks of file transfer functions for Windows. The algorithm realizes the peer-to-peer file transfer, one-to-N inquiry/multi-response file transfer and one-to-N file distribution in the same data field based on communication patterns provided by the ADP. The peer-to-peer file transfer is implemented through a peer-to-peer communication path, one-to-N inquiry/multi-response file transfer and one-to-N file distribution are implemented through multicast commtmieation. In this algorithm, a file to be transferred is named with a GUID ( global unique identification), every data packet is marked with a sequence number, and file-receiving in parallel is implemented by caching DPOs (data processing objects) and multithread technologies. The algorithm is applied in a simulation system of the decentralized control platform, and the test results and long time stable mrming prove the feasibility of the algorithm.     

二语习得中语法层面的母语负向迁移

母语迁移研究在第二语言习得理论中占重要地位．语言的标记性与母语迁移有着息息相关的联系．母语迁移对二语学习者的影响主要表现在语音、词汇、语法以及文化四个方面．从语法层面上,其表现形式主要体现为人称与数的变化、语序、被动结构、时间意义的表达、主从句的连接结构等多方面．因此,在语法教学中,教育工作者应注重分析母语负向迁移,帮助英语学习者克服母语干扰．     

Pressure drop and heat transfer of catalyzed diesel particulate filters due to changes in soot loading and flow rate

When soot particles are loaded in a diesel particulate filter, it causes increase in back pressure of the exhaust system. To minimize this pressure drop due to DPF, the filter needs to be regenerated after a certain amount of soot has been accumulated. It is crucial to estimate the correct amount of soot that has been accumulated by measuring the differential pressure. It is also important to understand changes in pressure drop due to flow rate variations of the exhaust gas, since the pressure drop would be influenced by the exhaust flow rate as well as the amount of soot. Furthermore, the heat transfer characteristics of the catalyzed diesel particulate filter (CDPF) are another major issue, as the filter is occasionally exposed to high temperature gas. This study presents the characteristics of pressure drop according to the variation of soot loading and the mass flow rate in CDPF. In addition, heat transfer characteristics in the filter was investigated when a high temperature gas flows into the CDPF. Tests were performed in several CDPF samples having varying amounts of catalyst coating. Experimental results indicate that rig-based experiments are useful in understanding the characteristics of pressure drop in the CDPF. In the cake filtration region, a pressure drop has a proportional relationship according to soot loading and mass flow rate. It was found that an increased catalyst coating may lead to enhanced convective heat transfer.     

沥青路面微波热再生传热模型与解法

为了获得沥青路面微波热再生过程的温度场,基于传热学理论,分析了微波加热过程的传热形式,建立了三维非稳态的传热模型,研究了传热模型的边界条件,求解了对流换热系数及辐射换热发射率,根据能量守恒原理,确定了内热源强度,实现了电场到热场的转化。采用交替方向显(ADE)格式,提出了传热模型的数值解法,对实测温度进行拟合,并建立了传热边界条件数学模型,仿真求得模型的可视化数值解。结果发现:加热450 s时,沥青混合料大部分区域接近70℃,加热600 s时,达到80℃,加热到750 s时,温度迅速上升到110℃左右,这表明热量传递随加热时间是非线性的,必须精确地选择加热时间以保证修补质量。     

肝动脉桥式置管转流对供肝及胆道组织细胞凋亡的保护作用

目的验证肝动脉桥式置管转流这一方法是否能够减轻肝动脉缺血(hepatic artery ischemia,HAI)引起的肝胆细胞凋亡。方法应用简易犬肝自体原位移植模型,将24只杂交犬随机分为肝动脉缺血组(HAI组,8只)、肝动脉桥式置管转流组(TBB组,8只)及对照组(8只)。在制模后,3组动物均于冷灌注后不同时点切取肝脏、胆道组织,分别用戊二醛及40 g/L多聚甲醛溶液固定,进行电镜观察和TUNEL染色,观察肝胆组织形态学改变及细胞凋亡情况,并计算两组的凋亡指数。结果在冷灌注后2 h,HAI组电镜下出现较明显的肝胆细胞凋亡现象;肝动脉桥式置管转流组肝胆细胞凋亡现象少见;对照组难以找到凋亡肝胆细胞。TUNEL法染色切片显示,冷灌注后3组肝胆组织内均有少量凋亡细胞,其凋亡指数相差不大(P>0.05);随冷灌注后时间的延长,3组凋亡细胞的数量均有所增加,但HAI组凋亡指数的升高更为显著,肝动脉桥式置管转流组次之,对照组变化不大,3组间差别有统计学意义(P<0.01)。结论肝动脉桥式置管转流对肝移植时肝动脉缺血所导致的肝胆细胞凋亡具有显著保护作用,应在继续完善改进的基础上实施于临床。     

自行车交通与轨道交通合理换乘方法

自行车与城市轨道交通的有效衔接能够弥补轨道交通自身的缺陷,扩大轨道交通服务范围。当前,我国部分城市对自行车与城市轨道交通的衔接重视不够,换乘率普遍较低,在一定程度上影响了城市轨道交通功效的发挥。结合我国目前的交通形势,阐述了自行车交通换乘轨道交通的积极意义,并对各种类型换乘站衔接设施的布局模式及衔接设施运营管理模式方面的问题进行了探讨。