基于PC104总线数据采集卡的设计

介绍了一款基于PCI04总线数据采集卡的设计方法,描述了采集卡硬件接口电路的设计,主要包括A／D转换、开关量的输入输出以及定时计数功能模块的实现．该采集卡应用于真空断路器机械特性检测仪中,实现采集模拟量,开关量以及定时计数等主要功能。     

Combustion and emission characteristics of BD20 reformed by ultrasonic energy for different injection delay and EGR rate in a diesel engine

The purpose of this study is to understand the operational characteristics of a diesel engine that uses BD20 reformed by ultrasonic energy irradiation. In particular we study the effects of tuning injection delay and EGR rate. BD containing about 10% oxygen has attracted attention due to soaring crude oil prices and environmental pollution. This oxygen decreases soot by promoting combustion, but it also increases NOx. To solve this problem, injection timing may be delayed or an EGR system may be applied. These adjustments normally lower engine power and increase exhaust emission but, in using fuel reformed by ultrasonic energy irradiation (which is changed physically and chemically to promote combustion), we may hope to circumvent this problem. To control the duration of the ultrasonic energy irradiation, the capacity of the chamber in an ultrasonic energy fuel supply system was tested at 550cc and 1100cc capacities. As for the results of the experiment, we could identify the optimum EGR rate by investigating the engine performance and the characteristics of exhaust emissions according to the injection timing and the EGR rate while ultrasonically irradiated BD20 was fed to a commercial diesel engine. With UBD20 (at an injection timing of BTDC 16°), the optimum EGR rate, giving satisfactory engine performance and exhaust emissions characteristics, was in the range of 15∼20%.     

典型集约化污水处理厂工艺设计——以南京某项目为例

南京大厂污水处理厂新建工程(一期)设计规模9万m³/d，出水执行《城镇污水处理厂污染物排放标准》(GB 18918—2002)一级A标准。介绍和分析了大厂污水处理厂工程设计难点，由此确定一期工程处理的工艺方案选择和设计参数，确定了改良型AAO+磁混凝沉淀+反硝化深床滤池+污泥深度浓缩脱水的处理工艺。通过工艺选择和组团式布局解决了用地紧张的难题，利用先进的设备技术保障准Ⅳ出水达标的可行性。对同类标准工程设计有一定的借鉴意义。     

面向铲装作业场景的自动驾驶矿车路径规划方法研究

针对铲装作业场景复杂多变、矿车路径规划实时性及安全性要求高的特点，提出一种基于引导式变步长混合A*算法的路径规划方法。通过建立维诺图获取矿区路网并提取关键点作为方向引导，提升探索效率的同时避免车辆在U形障碍物处陷入局部最优；引入自适应变步长算法并改进启发函数，进一步提高规划效率及路径安全性；通过矿区实车场景试验验证算法有效性。试验结果表明，本路径规划方法满足矿车复杂场景要求，规划时间相比原引导式算法降低68%，路径到障碍物平均距离增加了11%，路径曲率变动次数减少45%，显著提高了计算效率与路径质量。     

921A调质高强度合金钢塑性收缩量

以921A调质高强度钢在热传导温度场影响下产生的塑性收缩量为主要研究对象，选取船舶局部典型结构进行片体试验，结合分段建造施工工艺要素进行数据测量。进行数据处理，确定921A钢在建造过程中产生的收缩量和收缩因数，并转化为相应的精度加成因数，最终得到精度补偿量，可为实际船体结构建造策划设计的精度控制提供依据。