Organochlorine pesticides (OCPs) have been a major environmental issue, attracting much scientific concern because of their nature of toxicity, persistence, and endocrine disrupting effects. Soil samples were collecte...Organochlorine pesticides (OCPs) have been a major environmental issue, attracting much scientific concern because of their nature of toxicity, persistence, and endocrine disrupting effects. Soil samples were collected from ten college school yards in Beijing in 2006 and analyzed to determine fifteen OCPs. Dichlorodiphenyltrichloroethanes (DDTs) were found to be the main pollutants, accounting for 93.70% of total OCPs, followed by hexachlorohexanes (HCHs) (2.25%) and hexachlorobenzene (HCB) (1.82%). Content...展开更多
为提升煤场的管理水平,并保证不同环境下的盘煤精度,研究Unity3D在工业煤场三维可视化中的关键技术。该技术的数据采集模块利用激光扫描仪采集工业煤场的点云数据,并通过基于面片的多视角立体视觉(PMVS)算法重建该数据;随后将该数据输...为提升煤场的管理水平,并保证不同环境下的盘煤精度,研究Unity3D在工业煤场三维可视化中的关键技术。该技术的数据采集模块利用激光扫描仪采集工业煤场的点云数据,并通过基于面片的多视角立体视觉(PMVS)算法重建该数据;随后将该数据输入至三维场景构建模块,该模块利用Dynamo for Revit软件生成煤场的三维场景模型。场景渲染和可视化模块在Unity3D技术的支撑下渲染该模型,并完成模型可视化展示;结合构建的模型结果和点云数据完成煤场各区域煤堆的体积计算,实现煤场盘点。测试结果显示,该技术生成的三维场景模型能完整保留煤堆的形态细节,且能可靠完成不同高度煤堆的体积计算。展开更多
An efcient approach for yard crane(YC)scheduling is proposed in this paper.The definition of task group for YC scheduling is proposed.A mixed integer programming(MIP)model is developed.In the model,objective functions...An efcient approach for yard crane(YC)scheduling is proposed in this paper.The definition of task group for YC scheduling is proposed.A mixed integer programming(MIP)model is developed.In the model,objective functions are subject to the minimization of the total delay of complete time for all task groups and the minimization of block-to-block movements of YCs.Due to the computational scale of the non-deterministic polynomial(NP)complete problem regarding YC scheduling,a rolling-horizon decision-making strategy is employed to solve this problem,by converting the MIP model into another MIP model in the scheduling of each rolling period.Afterwards,a heuristic algorithm based on modified A*search is developed to solve the converted model and obtain near optimal solution.Finally,the computational experiments are used to examine the performance of the proposed approach for YC scheduling.展开更多
基金the National Basic Re-search Program (973) of China (No. 2003CB415005)the National Natural Science Foundation of China (No.20607026/B0702, 20437020)
文摘Organochlorine pesticides (OCPs) have been a major environmental issue, attracting much scientific concern because of their nature of toxicity, persistence, and endocrine disrupting effects. Soil samples were collected from ten college school yards in Beijing in 2006 and analyzed to determine fifteen OCPs. Dichlorodiphenyltrichloroethanes (DDTs) were found to be the main pollutants, accounting for 93.70% of total OCPs, followed by hexachlorohexanes (HCHs) (2.25%) and hexachlorobenzene (HCB) (1.82%). Content...
文摘为提升煤场的管理水平,并保证不同环境下的盘煤精度,研究Unity3D在工业煤场三维可视化中的关键技术。该技术的数据采集模块利用激光扫描仪采集工业煤场的点云数据,并通过基于面片的多视角立体视觉(PMVS)算法重建该数据;随后将该数据输入至三维场景构建模块,该模块利用Dynamo for Revit软件生成煤场的三维场景模型。场景渲染和可视化模块在Unity3D技术的支撑下渲染该模型,并完成模型可视化展示;结合构建的模型结果和点云数据完成煤场各区域煤堆的体积计算,实现煤场盘点。测试结果显示,该技术生成的三维场景模型能完整保留煤堆的形态细节,且能可靠完成不同高度煤堆的体积计算。
基金the National Natural Science Foundation of China(No.71101090)the Shanghai Top Academic Discipline Project-Management Science&Engineering,the Shanghai Municipal Education Commission Project(Nos.12ZZ148,13YZ080 and 14YZ112)+1 种基金the Ministry of Transport Research Projects(No.2012-329-810-180)the Shanghai Maritime University Research Project(Nos.20120102 and 20110019)
文摘An efcient approach for yard crane(YC)scheduling is proposed in this paper.The definition of task group for YC scheduling is proposed.A mixed integer programming(MIP)model is developed.In the model,objective functions are subject to the minimization of the total delay of complete time for all task groups and the minimization of block-to-block movements of YCs.Due to the computational scale of the non-deterministic polynomial(NP)complete problem regarding YC scheduling,a rolling-horizon decision-making strategy is employed to solve this problem,by converting the MIP model into another MIP model in the scheduling of each rolling period.Afterwards,a heuristic algorithm based on modified A*search is developed to solve the converted model and obtain near optimal solution.Finally,the computational experiments are used to examine the performance of the proposed approach for YC scheduling.
