地理信息中台在智慧城市中的应用——以南京市为例

空间数据是智慧城市不可或缺、基础性的数据资源,又是其他信息交换、共享与协同的载体。本文在研究物联网、云计算、大数据、人工智能、空间信息等信息技术的基础上,基于“中台”架构理念,结合南京市不同领域对空间信息的应用需求,提出集空间数据、异构GIS平台服务、通用地理信息业务及技术于一体的“地理信息中台”能力建设,作为智慧南京的地理信息智慧“底板”,真正实现“一处建设,多处应用”。     

西方绅士化研究进展

从绅士化概念的提出与发展入手,回顾了西方绅士化现象的阶段特征与趋势、西方绅士化研究的四个重要阶段,从绅士化的类型衍化、绅士化概念工具的再发展、绅士化效应与抵抗、新自由城市主义与绅士化、尺度转向与星球绅士化等方面分析当代西方绅士化研究的新特点.在展望西方绅士化实证研究、理论建构、后效应对与研究方法的基础上,认为中国绅士化的研究应当重点关注本体论与认识论、前置条件、结构动力与制度条件的独特性.     

基于流固耦合的电缆中间接头防爆盒抗爆能力模拟研究

为分析内爆炸作用下电缆中间接头防爆盒的抗爆能力,建立了电缆中间接头在加装防爆盒情况下的数值模型,采用流固耦合的方法分别对防爆盒典型结构爆炸过程,不同中心半径比、不同端部半径比、不同形状、不同材料及是否灌装密封胶的影响进行了模拟研究。结果表明,防爆盒壳体上爆心环面及两端是承受爆炸冲击力最大的位置,应当重点防护;防爆盒的抗爆能力随着中心半径比的增大有较大增强,随着端部半径比的增大有较小增强;在相同中心半径情况下圆柱形防爆盒的抗爆能力强于阶梯形防爆盒;铝镁合金防爆盒在相同仿真条件下被炸开,其抗爆能力弱于不锈钢材质;灌装密封胶对防爆盒有较为明显的作用,其中灌装聚氨酯密封胶的表现略优于灌装环氧树脂密封胶。     

Effect of working position and cold environment on muscle activation level and fatigue in the upper limb during manual work tasks

Several occupational groups are exposed to periods of low ambient temperatures while performing manual work tasks outdoors. Work tasks typically include heavy lifting, tool handling, and overhead work. This study evaluated the effect of working position and cold environment on muscle activation level (%RMS_max) and fatigue in the upper limb during manual work tasks. Fourteen male participants (25 ± 3 years, 80.9 ± 6.4 kg, 182 ± 5 cm) completed a 2-h test protocol consisting of five test periods alternating with four work periods, wearing identical sets of clothing, under cold (−15 °C) and control (5 °C) conditions. The work periods consisted of manual work at the hip level, manual overhead work, and a lifting exercise. The test periods consisted of isometric maximal voluntary contractions (MVC) and seated rest. Skin temperatures decreased during cold exposure, especially in the extremities. %RMS_max in the forearm was higher in the cold condition both during overhead work and work at the hip level than that for the same work in the control condition, especially at the end of the test when the difference was approximately 25% (equating to 2–3 %RMS_max). For the middle deltoid muscle, the %RMS_max was approximately three times (or 10 %RMS_max) higher during overhead work than work at the hip level, but there was no additional cost of working in the cold. Signs of deltoid muscle fatigue (decrease in electromyography median power frequency and an increase in %RMS_max) were observed during the overhead work periods in both temperature conditions. No decrease in MVC, as a sign of overall muscle fatigue, was observed in either condition.Relevance to industryThis study demonstrated that when wearing suitable cold-weather protective clothing, the adverse effect of work posture is much higher than that of cold on muscle demand and physical strain.     

锅炉二次风道流动特性的模拟优化

以武汉武锅能源工程有限公司设计的二次风道为对象,运用数值模拟的方法考查了改造前后二次风道各出口空气的速度分布和质量流量分配情况。结果表明,通过布置弧形挡板,风道出口速度的均匀性显著提升,最大变异系数Cv由29%下降到9%,而且还避免了因风速不均引起的烧边现象。此外,改进后风道各出口空气的流量分配非常接近理想工况,与理想工况的偏差从9.9%缩小到2.1%。     

刮板输送机挡板槽帮减重及有限元分析

针对刮板输送机挡板槽帮进行减重,并基于ANSYS Workbench研究了减重前后挡板槽帮的应力状态,对在同等载荷下的应力分布进行了对比,从而确定了改进后挡板槽帮可代替原有挡板槽帮,并且达到减重、降成本的目的。     

LD27-2油田稠油油藏蒸汽吞吐中后期注采参数优化研究

蒸汽吞吐是稠油油藏开发的最有效措施之一，但是对于海上油田的特殊条件，在进行蒸汽吞吐3~4轮后，即意味着进入蒸汽吞吐中后期。此时，如何调整注采参数，是海上稠油油藏高效开发的关键。针对LD27-2油田稠油油藏的开发特点，在地质建模和高度历史拟合的情况下，对LD27-2油田稠油油藏开发状况进行多轮次预测；基于生产历史拟合的油藏数值模型，开展了不同蒸汽干度、注汽强度、注汽强度递增等条件下A22H井和A23H井蒸汽吞吐至开采至10年的油藏数值模拟，明确不同注采参数的影响规律，优化了LD27-2油田稠油油藏蒸汽吞吐中后期注采参数。     

Numerical and experimental study of the effect of a froth baffle on flotation cell performance

In this work, the effect of a froth baffle on flotation performance is investigated both experimentally and numerically. Flotation experiments with an artificial ore comprised of 80% silica as gangue and 20% limestone as floatable component were carried out to compare the flotation performance of a baffled froth system against an un-baffled froth system. The effect of the baffle’s inclination angle to the horizontal was also studied. Results indicated that a froth baffle has a profound effect on both recovery and grade. The presence of a froth baffle resulted in an increase in grade at the expense of recovery. The decrease in limestone recovery with the introduction of a froth baffle was found to be a function of the baffle’s inclination angle i.e. recovery decreased as the inclination angle becomes more acute. Water recovery as well as entrainment recovery herein represented by silica recovery decreased with decrease in baffle’s inclination angle. Numerical techniques were employed to model the experimental results. The 2D stream function equation/Laplace equation which is known to be adequate in describing froth transport was solved subject to boundary conditions that represent the presence of baffles. A solution was developed using finite difference methods on a rectangular map obtained using Schwarz–Christoffel (SC) mapping. Results from the simulations indicated a change in particle residence time distribution in a manner that reduces spread. The changes in residence time distribution helped in developing an explanation of the experimental data.     

中小学信息技术上机考试系统的设计与实现

介绍针对学校现有硬件与网络资源而开发的,适用于中小学信息技术学科的上机考试系统。着重介绍系统功能模块设计、系统运行流程规划及系统实现中关键问题的解决方法。     

提高自组织线性表查找性能的新方法

自组织线性表在非等概率查找中具有较好的效率。本文在原有3种基本构造策略的基础上，提出一种新方法——移至中位策略。该策略优化自组织线性表中记录的调整方式，减少了累计记录比较次数，从而提高了查找响应速度。在实验测试中，提出平稳的查找过程和非平稳的查找过程的概念，并分别设计相应的测试用例。实验结果表明，移至中位策略的综合性能最好。