摘要：[目的]探究海绵化程度与地表径流水质的关系,为缓解当前地表径流污染的海绵设施建设提供理论依据。[方法]以国家首批海绵城市试点嘉兴市为例,选取20个不同海绵化程度的项目为研究单元,建立可表征海绵设施类型、数量和布局等海绵化程度的指标,并采用冗余分析、偏最小二乘法、Origin拟合方程等方法进行分析。[结果]①样本中居住小区和公共建筑区域的水质均未满足地表水Ⅳ类及污水排放二级标准;已改造建设用地水质普遍优于未改造建设用地。②绿地和有效不透水下垫面(effective impervious area,EIA)比例是影响径流水质的关键因素,其中悬浮物(SS),生化需氧量(BOD 5)和化学需氧量(COD)是主要受影响指标。③为使径流水质达到海绵城市建设要求,不同海绵化程度下的用地需要管控的指标阈值有差异。[结论]EIA≈0时,绿地比例应不低于31%;EIA=0.04(TIA)1.7时〔其中TIA(total impervious area)为总不透水下垫面〕绿地比例应不低于38.5%;EIA=TIA时,绿地比例应不低于47%;若维持现行的城市绿地比例(约为35%)建设标准,EIA比例应不超过9%。

摘要：简要分析了HIRFL SFC与SSC之间的束流匹配关系,给出了新高频腔的频率范围。利用经典三维电磁场数值模拟软件MAFIA对SSC新高频腔体进行了模拟计算,得出了SSC新高频腔体的相关物理参数,并对频率范围、Q值、并联阻抗和电压分布等参数进行了分析。高频腔体的模拟计算结果完全符合SSC回旋加速器改造的物理设计及空间结构要求。

摘要：根据加速器高频控制系统网络化和自动化的要求,设计了一种基于Profibus-DP和Ethernet的并适用于加速器高频系统强磁场运行环境下的控制系统。系统采用S7-300PLC和S7-200PLC为核心控制设备,并以交换机为主要通信设备,构建了加速器高频系统控制网络。利用STEP7、Microwin4.0、Protool和Wincc完成PLC程序设计和上位机HMI设计。文中重点介绍了系统的网络结构、频率微调、硬件配置、软件设计。该系统设计简化了网络结构,提高了系统的可靠性和稳定性。

摘要：海绵城市建设是多主体参与、多要素协同的复杂工程,在推进过程中受到了多重制约因素的交互影响。选取国家首批海绵试点城市浙江省嘉兴市作为案例研究对象,通过对海绵城市相关参与人员的深度访谈,依据扎根理论,对访谈文本进行编码分析,构建海绵城市建设制约因素模型。研究表明,理念、资源、组织和制度是影响海绵城市推进的四大因素,其中理念认知为内在驱动力因素,资源和组织是内部情境因素,制度为外部情境因素,四者相辅相成,共同作用,推动(或阻碍)着海绵城市建设。基于此,应采取优化资源配置及组织结构等举措,为海绵城市的有效推进提供科学依据。

摘要：Significant transient beam loading effects were observed during beam commissioning tests of prototype II of the injector for the accelerator driven sub-critical （ADS） system, which took place at the Institute of Modern Physics, Chinese Academy of Sciences, between October and December 2014. During these tests experiments were performed with continuous wave （CW） operation of the cavities with pulsed beam current, and the system was configured to make use of a prototype digital low level radio frequency （LLRF） controller. The system was originally operated in pulsed mode with a simple proportional plus integral and deviation （PID） feedback control algorithm, which was not able to maintain the desired gradient regulation during pulsed 10 mA beam operations. A unique simple transient beam loading compensation method which made use of a combination of proportional and integral （PI） feedback and feedforward control algorithm was implemented in order to significantly reduce the beam induced transient effect in the cavity gradients. The superconducting cavity field variation was reduced to less than 1.7% after turning on this control algorithm. The design and experimental results of this system are presented in this paper.