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Fast Parallel Algorithm for Slicing STL Based on Pipeline

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Chinese Journal of Mechanical Engineering 2016年第3期29卷 549-555页

作者： MA Xulong LIN Feng yao bo Key Laboratory for Advanced Materials Processing Technology Ministry of Education of China Tsinghua University Department of Mechanical Engineering Army Aviation Institute of PLA

In Additive Manufacturing field, the current researches of data processing mainly focus on a slicing process of large STL files or complicated CAD models. To improve the efficiency and reduce the slicing time, a parallel algorithm has great advantages. However, traditional algorithms can＇t make full use of multi-core CPU hardware resources. In the paper, a fast parallel algorithm is presented to speed up data processing. A pipeline mode is adopted to design the parallel algorithm. And the complexity of the pipeline algorithm is analyzed theoretically. To evaluate the performance of the new algorithm, effects of threads number and layers number are investigated by a serial of experiments. The experimental results show that the threads number and layers number are two remarkable factors to the speedup ratio. The tendency of speedup versus threads number reveals a positive relationship which greatly agrees with the Amdahl＇s law, and the tendency of speedup versus layers number also keeps a positive relationship agreeing with Gustafson＇s law. The new algorithm uses topological information to compute contours with a parallel method of speedup. Another parallel algorithm based on data parallel is used in experiments to show that pipeline parallel mode is more efficient. A case study at last shows a suspending performance of the new parallel algorithm. Compared with the serial slicing algorithm, the new pipeline parallel algorithm can make full use of the multi-core CPU hardware, accelerate the slicing process, and compared with the data parallel slicing algorithm, the new slicing algorithm in this paper adopts a pipeline parallel model, and a much higher speedup ratio and efficiency is achieved.

关键词： additive manufacturing STL model slicing algorithm data parallel pipeline parallel

基于离散元的钢渣透水沥青混合料疲劳损伤数值仿真

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江苏大学学报（自然科学版） 2025年第1期46卷 98-104页

作者：刘振辉陈雪琴董侨姚波范进南京理工大学理学院江苏南京210094 南京理工大学安全科学与工程学院江苏南京210094 东南大学交通学院江苏南京211189 东南大学道路交通工程国家级实验教学示范中心江苏南京211189

采用钢渣替换透水沥青混合料中部分玄武岩粗集料,开展室内疲劳试验及数值仿真,研究钢渣透水沥青混合料的疲劳性能.基于CT扫描获取图像,通过阈值分割将混合料中钢渣、玄武岩、沥青砂浆和孔隙进行区分,导入颗粒流程序(PFC),建立颗粒直径为... 详细信息

采用钢渣替换透水沥青混合料中部分玄武岩粗集料,开展室内疲劳试验及数值仿真,研究钢渣透水沥青混合料的疲劳性能.基于CT扫描获取图像,通过阈值分割将混合料中钢渣、玄武岩、沥青砂浆和孔隙进行区分,导入颗粒流程序(PFC),建立颗粒直径为0.4 mm的钢渣透水沥青混合料离散元模型,基于宏观和细观力学参数转换及虚拟强度试验进一步校正细观力学参数,开展虚拟疲劳损伤数值模拟,得到重复荷载作用下试件微裂纹扩展路径及疲劳寿命.结果表明:虚拟强度试验能够较好地模拟钢渣透水沥青混合料试件荷载与位移关系曲线,试件裂纹扩展路径符合实际断裂情况,裂纹的分布主要沿着模型内部孔隙处扩展;虚拟疲劳损伤模型能够较好地描绘平行黏结模型的黏结直径随荷载作用次数的增加而减小、随着平行黏结接触颗粒间的拉应力增大而加速减小的趋势,虚拟疲劳损伤模型计算结果和室内疲劳损伤试验结果较为接近,误差不到10%,可有效预测高应力比下钢渣透水沥青混合料的疲劳寿命.

关键词：钢渣透水沥青混合料疲劳损伤离散元方法裂纹扩展

Characteristics and influencing factors of sediment deposition-scour in the Sanhuhekou-Toudaoguai Reach of the upper Yellow River,China

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International Journal of Sediment Research 2018年第3期33卷 303-312页

作者： bo yao Qingquan Liu Key Laboratory for Mechanics in Fluid Solid Coupling Systems Institute of mechanics Chinese Academy of Sciences Department of Mechanics School of Aerospace Engineering Beijing Institute of Technology

The annual changes of sediment deposition-scour on the riverbed in the Sanhuhekou-Toudaoguai Reach of the upper Yellow River during the years 1952-2010 were investigated based on runoff and sediment transport observations from the Sanhuhekou and Toudaoguai hydrological stations. Multiple influencing factors such as reservoir operations, tributary inflows, as well as runoff and sediment loads from the Shidakongdui area were analyzed. The results show that even though the sediment loads from the major sources, the Shidakongdui area as well as the upstream tributaries such as the Qingshui River and the Zuli River have reduced especially since the 2000 s as a result of enhanced water-soil conservation measures and improvement of vegetation cover, the study reach was still generally in a status of cumulative aggradation. This is mainly due to the joint operations of the Liujiaxia Reservoir and the Longyangxia Reservoir, which significantly reduced the annual runoff and sediment loads at the Sanhuhekou Crosssection. The reservoirs also remarkably altered the summer flood characteristics of the study reach, inducing the shape of the annual flow curve changing from a ’single-peak’ into a ’doublepeak’. These alternations sharply decreased the sediment transport capacity of flooding in the summer flood season which yields more than 90% of the sediment loads, leading to an unbalanced relation between the water and sediment. In addition, the estimated incoming sediment coefficient of the Sanhuhekou Crosssection ranged from 0.003 to 0.014 kg s/m~6, of which 0.004 kg s/m~6 was suggested as a rough critical value to determine the scour or deposition status of the study reach.

关键词： Upper Yellow River Sanhuhekou-Toudaoguai Reach Sediment deposition Incoming sediment coefficient Runoff Sediment loads

A pilot scale anoxic/oxic membrane bioreactor(A/O MBR) for woolen mill dyeing wastewater treatment

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Journal of Environmental Sciences 2003年第4期15卷 449-455页

作者： ZHENG Xiang FAN yao bo WEI Yuan song Department of Water Pollution Control Technology Research Center for Eco Environmental SciencesChinese Academy of SciencesBeijing 100085China.

A pilot scale(10 m 3/d) anoxic/oxic membrane bioreactor(A/O MBR) was tested for dyeing wastewater treatment of woolen mill without wasting sludge in 125 days operation. Results showed that the effluent quality was excellent, i.e. effluent COD less than 25 mg/L, boD 5 under 5 mg/L, turbidity lower than 0 65 NTU, and colour less than 30 DT, and met with the reuse water standard of China. The removal rates of COD, boD 5, colour, and turbidity were 92 4%, 98 4%, 74% and 98 9%, respectively. Constant flux operation mode was carried out in this study, and backwash was effective for reducing membrane fouling and maintaining constant flux. Membrane fouling had heavy impact on energy consumption. More attention should be paid on pipe selection and design for the sidestream MBR system, too.

关键词： activated sludge backwash constant flux dyeing wastewater treatment membrane bioreactor (MBR) woolen mill

Selection of leading industries for coal resource cities based on coupling coordination of industry's technological innovation

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International Journal of Mining Science and Technology 2012年第3期22卷 317-321页

作者： Du Jiming Yu bo yao Xilong School of Management. Harbin Institute of Technology Harbin 150001 China

Taking the city of Qitaihe is as an example in order to provide practical methods for the selection of leading industries for coal resource cities, this paper establishes the specific operation scheme for selection of leading industries according to the actual situation of coal resource cities based on the theory of coupling coordination together with the coupling coordination for technological innovation. The results show that the degree for coupling coordination of the technological innovation for each alternative industry differentiates with the development of coal resource cities. For example, the average degree of food processing industry from agricultural produce is 0.9. Therefore, coal resource cities should develop some industries related to coal industry, such as coking industry, some chemical and medicines industry and non-metallic mineral products manufacturing, in the near future, however, some industries with greater market and influence potentials and low carbon emissions should be attached much importance to in the future.

关键词： Industrial technology innovationCoupling coordinationCoal resources citySelection of industries

Pole Assignment for Uncertain System in Mixed Region

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Pole Assignment for Uncertain System in Mixed Region

Application of stapling devices in liver surgery: Current status and future prospects

第25届中国控制与决策会议

作者： Zhijuan An Fuzhong Wang bo yao College of Mathematics and System Science Shenyang Normal University Shenyang Institute of Engineering Shenyang

ISBN: (纸本)9781467355322

For a class of uncertain linear system, using state feedback, it gives a sufficient condition of placing all poles of the closed-loop system in mixed region, in terms of linear matrix inequality （LMI）. At the same time, it presents a way to design the reliable controller. When faults occur, the closed-loop poles of reliable system are still in the specified mixed region. Moreover, the numerical example illustrate the design method is feasible and effective in the end of this paper.

关键词： uncertain linear system linear matrix inequality pole assignment reliable control

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World Journal of Gastroenterology 2016年第31期22卷 7091-7098页

作者： Dian-bo yao Shuo-Dong Wu Second Department of General Surgery Shengjing Hospital of China Medical University

The liver is a vascular-rich solid organ. Safe and effective dissection of the vessels and liver parenchyma, and control of intraoperative bleeding are the main concerns when performing liver resection. Several studies have confirmed that intraoperative blood loss and postoperative transfusion are predictors of postoperative morbidity and mortality in liver surgery. Various methods and instruments have been developed during hepatectomy. Stapling devices are crucial for safe and rapid anastomosis. They are used to divide hepatic veins and portal branches, and to transect liver parenchyma in open liver resection. In recent years, laparoscopic liver surgery has developed rapidly, and is now preferred by many surgeons. Stapling devices have also been gradually introduced in laparoscopic liver surgery, from dividing vascular and biliary structures to parenchymal transection. This may be because staplers make manipulation more simple, rapid and safe. Even in single incision laparoscopic surgery, which is recognized as a new minimally invasive technique, staplers are also utilized, especially in left lateral hepatectomy. For safe application of stapling devices in liver surgery, more related designs and modifications, such as application of a suitable laparoscopic articulating liver tissue crushing device, a staple line reinforcement technique with the absorbable polymer membrane or radiofrequency ablation assistance, are still needed. More randomized studies are needed to demonstrate the benefits and find broader indications for the use of stapling devices, to help expand their application in liver surgery.

关键词： Staplers Liver resection Laparoscopy

Reuse rate of treated wastewater in water reuse system

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Journal of Environmental Sciences 2005年第5期17卷 842-845页

作者： FAN yao-bo YANG Wen-bo LI Gang WU Lin-lin WEI Yuan-song Department of Water Pollution Control Technology Research Centre for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085China

A water quality model for water reuse was made by mathematics induction. The relationship among the reuse rate of treated wastewater（R）, pollutant concentration of reused water（ Cs ）, pollutant concentration of influent（ C0）, removal efficiency of pollutant in wastewater（ E）, and the standard of reuse water were discussed in this study. According to the experiment result of a toilet wastewater treatment and reuse with membrane bioreactors, R would be set at less than 40%, on which all the concerned parameters could meet with the reuse water standards. To raise R of reuse water in the toilet, an important way was to improve color removal of the wastewater.

关键词： water quality model reuse rate wastewater treatment water reuse

Microstructure and mechanical properties of Ti-6Al-4V components fabricated by laser micro cladding deposition

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Rare Metals 2015年第7期34卷 445-451页

作者： bo yao Xu-Long Ma Feng Lin Wen-Jun Ge Key Laboratory for Advanced Materials Processing Technology Ministry of Education of China Key Laboratory for Biomanufacturing and Rapid Forming Technology Department of Mechanical Engineering Tsinghua University Department of Mechanical Engineering Army Aviation Institute of Chinese People’s Liberation Army

Laser micro cladding deposition manufacturing(Ll CDM) is a newly developed rapid manufacturing method for *** Ll CDM technology adopts a novel powder feeding method based on alternating friction and inertia force, and this powder feeding method can effectively improve the accuracy and orientation of the powder injection, resulting in a smaller molten pool size and a higher cooling rate of liquid ***, the components fabricated by Ll CDM could obtain the finer microstructures and the improved mechanical *** is found that the components fabricated by Ll CDM are fully dense free of cracks or pores and exhibit columnar prior b grains with a finer acicular a0 phase *** microhardness(HV0.2) of the thin-wall component is HV 400–HV 500 in the majority part of the cross section and can reach about HV 850 in the top *** ultimate tensile strength(UTS) and elongation show insignificant dependence on the testing directions of the *** UTS is between 1,002 and 1,100 MPa, and the elongation is between 10.0 % and 14.7 %.

关键词： Laser micro cladding deposition Ti-6Al-4V Microstr