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基于虚拟仪器的柴油机模糊-PID调速控制研究

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柴油机 2017年第1期39卷 34-37页

作者：王东军袁志国费红姿李文辉海军驻大同地区军事代表室山西大同037036 哈尔滨工程大学动力与能源工程学院黑龙江哈尔滨150001

采用NI PCI6221多功能数据采集卡建立了基于虚拟仪器的柴油机速度控制系统,设计了增量式模糊-PID控制器。针对模糊-PID切换控制中出现的系统响应动态特性和稳定性不佳的问题,对切换控制器进行了优化;采用偏差及偏差变化率作为切换依据... 详细信息

采用NI PCI6221多功能数据采集卡建立了基于虚拟仪器的柴油机速度控制系统,设计了增量式模糊-PID控制器。针对模糊-PID切换控制中出现的系统响应动态特性和稳定性不佳的问题,对切换控制器进行了优化;采用偏差及偏差变化率作为切换依据及双阈值判断方法,有效改善了系统动态特性,提高了控制器切换稳定性。试验结果表明:优化后的柴油机模糊-PID调速控制系统在动态特性、稳定性上都取得了更好的控制效果。

关键词：柴油机调速特性虚拟仪器模糊-PID控制

Characterization of the Convoluted 3D Internetallic Phases in a Recycled Al Alloy by Synchrotron X-ray Tomography and Machine Learning

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Acta Metallurgica Sinica(English Letters) 2022年第1期35卷 115-123页

作者： Zhenhao Li Ling Qin Baisong Guo Junping yuan zhiguo Zhang Wei Li Jiawei Mi Institute of Advanced Wear Resistant and Functional Materials Jinan UniversityGuangzhou510632China Jewelry Institute Guangzhou Panyu PolytechnicGuangzhou511487China Department of Engineering University of HullEast YorkshireHullHU67RXUK

Fe-rich intermetallic phases in recycled Al alloys often exhibit complex and 3D convoluted structures and *** are the common detrimental intermetallic phases to the mechanical properties of recycled Al *** this study,we used synchrotron X-ray tomography to study the true 3D morphologies of the Ferich phases,Al_(2)Cu phases and casting defects in an ascast Al-5Cu-1.5Fe-1Si *** learning-based image processing approach was used to recognize and segment the diff erent phases in the 3D tomography image *** the studied condition,theβ-Al_(9)Fe_(2)Si_(2)andω-Al_(7)Cu_(2)Fe are found to be the main Fe-rich intermetallic ***β-Al_(9)Fe_(2)Si_(2)phases exhibit a spatially connected 3D network structure and morphology which in turn control the 3D spatial distribution of the Al_(2)Cu phases and the shrinkage *** Al_(3)Fe phases formed at the early stage of solidification aff ect to a large extent the structure and morphology of the subsequently formed Fe-rich intermetallic *** machine learning method has been demonstrated as a powerful tool for processing big datasets in multidimensional imaging-based materials characterization work.

关键词： Recycled Alalloy Solidifi cation Synchrotron X-ray tomography Machine learning Fe-rich intermetallic phases

How did the Tonga volcanic tsunami on January 15,2022,affect Chinese coasts?

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Science China Earth Sciences 2023年第5期66卷 1038-1046页

作者： Zongchen WANG zhiguo XU Ye yuan Huaiwei YANG Lining SUN Peitao WANG Tingting FAN National Marine Environmental Forecasting Center Ministry of Natural Resources(National Tsunami Warning CenterMinistry of Natural Resources)Beijing100081China Key Laboratory of Marine Hazards Forecasting National Marine Environmental Forecasting CenterMinistry of Natural ResourcesBeijing100081China

At 12:15 on January 15,2022(Beijing time),a massive eruption of the Hunga Tonga-Hunga Ha'apai volcano produced violent atmospheric fluctuations,which in turn generated a global tsunami through an abrupt air pressure shock upon the sea *** main components of tsunami waves,phase-locked waves and free gravity waves,were identified by significant differences in propagating speeds across the deep *** phase-locked wave propagated through the ocean basin synchronously with the atmospheric Lamb wave at an average speed of approximately 306 m/s,followed by the free gravity wave at a slower *** locked wave reached the coast of eastern Taiwan Island at about 20:00 on January 15,in coincidence with the Lamb wave ***,on the coast of Chinese mainland,tidal gauges did not record tsunami signals until at least 2 h after the Lamb wave *** analyses and numerical experiments both suggested that as a result of the incoming wave shoaling above the vast continental shelf of Chinese mainland,the locked wave was no longer trapped by the air pressure shock and gradually transformed into freely-propagating shallow water waves by slowing down its *** to the longlasting planetary atmospheric fluctuations circling the earth many times,the sea level oscillations continuously propagated onto the Chinese shelf,which resulted in the tsunami waves excited along the Chinese coasts for at least 36 *** maximum wave amplitude recorded on the coast of eastern Taiwan Island was 44 cm at Wushi,while on the coasts of eastern and southern Chinese mainland,the maximum amplitudes were 22 cm at Shipu and 13 cm at *** and wavelet analyses were performed to identify the major components of the tsunami waves on the Chinese *** results indicated that eastern Taiwan Island was impacted mainly by the waves with periods of approximately 10-40 *** mainland was hit by the evolved shallow water waves and subsequent free waves,with pe

关键词： Volcanic tsunami Atmospheric Lamb wave Phase-locked-wave Free gravity wave Shallow water wave

以项目式教学驱动面向新工科的化工原理实验创新——以中北大学为例

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化工高等教育 2021年第4期38卷 93-99页

作者：贾广信焦纬洲李裕李同川袁志国王海宾中北大学化学工程与技术学院山西太原030051 中北大学化工综合国家级实验教学示范中心山西太原030051

针对中北大学化工原理实验教学存在的问题,课程团队以项目式教学为抓手,从实验内容系统化设计、实验任务项目化教学、实验设施多功能化差异化改造、学习资源立体化保障、指导教师专业化分工、项目库建设动态化更新等方面开展教学改革实... 详细信息

针对中北大学化工原理实验教学存在的问题,课程团队以项目式教学为抓手,从实验内容系统化设计、实验任务项目化教学、实验设施多功能化差异化改造、学习资源立体化保障、指导教师专业化分工、项目库建设动态化更新等方面开展教学改革实践。此次教改有利于培养学生的实验规划和工程设计能力、实验操作和科学研究能力、团队协作和沟通交流能力,能够有效提升化工原理实验课程教学质量,同时有助于构建适应工程实际和产业需求的化工原理实验教学新模式,可为新工科背景下工程实验课程教学改革提供实践范例。

关键词：项目式教学新工科化工原理实验教学创新

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磷酸钠法烟气脱硫富液抗氧化性研究

山西化工 2015年第1期35卷 4-7,13页

作者：宋卫袁志国裴琼琼黄谷一张悦邹旭昌中北大学化工与环境学院山西太原030051

通过分析磷酸钠法烟气脱硫机理和亚硫酸钠氧化反应机理,采用动力学方法,设计正交实验,考察了亚硫酸钠浓度、空气流量、磷酸浓度、溶液pH值和温度5个因素对磷酸钠脱硫富液中亚硫酸钠氧化反应速率的影响。结果表明,各因素对亚硫酸钠氧化... 详细信息

通过分析磷酸钠法烟气脱硫机理和亚硫酸钠氧化反应机理,采用动力学方法,设计正交实验,考察了亚硫酸钠浓度、空气流量、磷酸浓度、溶液pH值和温度5个因素对磷酸钠脱硫富液中亚硫酸钠氧化反应速率的影响。结果表明,各因素对亚硫酸钠氧化速率影响的显著性顺序为：c（Na2SO3）〉cP〉pH〉T〉G。磷酸钠吸收剂能够抑制亚硫酸钠的氧化。实验操作范围内,磷酸钠脱硫富液中亚硫酸钠氧化速率为0.001 16mol·L-1·h-1~0.018 75mol·L-1·h-1。研究结果为磷酸钠烟气脱硫技术中硫酸钠的生成控制提供了理论指导。

关键词：烟气脱硫磷酸钠法氧化硫酸钠正交实验

Damage tolerance of fractured rails on continuous welded rail track for high-speed railways

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Railway Engineering Science 2021年第1期29卷 59-73页

作者： yuan Gao Ping Wang Kai Wang Jingmang Xu zhiguo Dong MOE Key Laboratory of High-Speed Railway Engineering Southwest Jiaotong UniversityChengdu 610031China School of Civil Engineering Southwest Jiaotong UniversityChengdu 610031China

Broken gap is an extremely dangerous state in the service of high-speed rails,and the violent wheel–rail impact forces will be intensified when a vehicle passes the gap at high speeds,which may cause a secondary fracture to rail and threaten the running safety of the *** recognize the damage tolerance of rail fracture length,the implicit–explicit sequential approach is adopted to simulate the wheel–rail high-frequency impact,which considers the factors such as the coupling effect between frictional contact and structural vibration,nonlinear material and real geometric *** results demonstrate that the plastic deformation and stress are distributed in crescent shape during the impact at the back rail end,increasing with the rail fracture *** axle box acceleration in the frequency domain displays two characteristic modes with frequencies around 1,637 and 404 *** limit of the rail fracture length is 60 mm for high-speed railway at a speed of 250 km/h.

关键词： Rail broken gap Explicit FE method Damage High-frequency impact Stress mechanism

右美托咪定对体外循环下心脏瓣膜置换手术患者的脑保护作用分析

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心血管外科杂志（电子版） 2018年第4期7卷 615-616页

作者：李小静吉晓丽蔡鹏举袁志国孙灿林泰州市人民医院麻醉科江苏泰州225300

目的对体外循环下心脏瓣膜置换手术患者输注右美托咪定,分析该药品对患者起到的脑保护作用。方法在2014年1月-2018年6月开展研究,研究样本均来自于我院实施体外循环下心脏瓣膜置换手术的52例患者,根据随机数字表法将样本平均分为生理盐... 详细信息

目的对体外循环下心脏瓣膜置换手术患者输注右美托咪定,分析该药品对患者起到的脑保护作用。方法在2014年1月-2018年6月开展研究,研究样本均来自于我院实施体外循环下心脏瓣膜置换手术的52例患者,根据随机数字表法将样本平均分为生理盐水注射的盐水组(26例)与右美托咪定注射的右美组(26例),两组使用方法相同且均在麻醉诱导前15min完成,记录并对比两组患者不同时间点内血浆S-100β蛋白、神经元特异性烯醇化酶(NES)。结果在T2、T3、T4阶段,右美组血浆S-100β蛋白[(3.68±1.02)μg/L、(4.02±1.04)μg/L、(6.03±1.07)μg/L]低于盐水组,NES[(16.73±2.98)μg/L、(19.41±3.79)μg/L、(23.44±3.80)μg/L]低于盐水组,差异显著(P<0.05)。结论对体外循环下心脏瓣膜置换手术患者输注右美托咪定,可改善患者的脑缺氧情况,起到显著的脑保护作用,应用价值显著。

关键词：体外循环心脏瓣膜置换手术右美托咪定脑保护

Effectively improving the extreme-pressure capacity of a class of intercalated zirconium phosphate materials

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Science China(Technological Sciences) 2024年第3期67卷 753-764页

作者： NIU WenXing ZHAO XinRui yuan Min HOU zhiguo LIU Lei XU Hong DONG JinXiang Shanxi Key Laboratory of Chemical Product Engineering Cllege of Chemical Engineering and TechnologyTaiyuan University of TechnologyTaiyuan 030024China School of Chemical and Environmental Engineering Pingdingshan UniversityPingdingshan 467000China

We studied different long-chain ammonium ions intercalated zirconium phosphate α-ZrP, methylamine intercalated ZrP(MAZrP), tetramethylammonium hydroxide intercalated ZrP(TMAH-ZrP), dodecyltrimethylammonium bromide intercalated ZrP(DTAB-ZrP), and stearyl trimethyl ammonium bromide intercalated ZrP(STAB-ZrP) as grease co-additives in combination with isobutylene sulfide(SIB). The grease with co-additives displayed excellent extreme-pressure and anti-wear ***, the combination of the longest chain ammonium ion intercalated zirconium phosphate, STAB-ZrP/SIB, had the best tribological properties. In comparison to α-ZrP, the advantage of STAB-ZrP was that it did not form a large area of the dense physical film like α-ZrP on the worn surface, but rather gave the SIB a chance to contact with the fresh metal surface to generate a chemical film. Therefore, the sub-micron physical film and nanoscale chemical film always exist side by side on the contact surface during the friction process. This intercalated α-ZrP/SIB additive has great potential for use in harsh operating conditions.

关键词： intercalatedα-ZrP/SIB physical film chemical film tribological properties

以全国大学生化工设计竞赛为契机，探索化工原理课程教学改革

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广东化工 2020年第1期47卷 141-142页

作者：申红艳李裕李同川袁志国王艳红中北大学化学工程与技术学院

全国大学生化工设计竞赛是化工类专业的最高级别赛事,作为培养学生动手能力、解决问题能力、创新能力和实践能力行之有效的途径,受到国内高校的广泛关注。本文以全国大学生化工设计竞赛为契机,结合化工原理课程教学的实际情况,从课堂教... 详细信息

全国大学生化工设计竞赛是化工类专业的最高级别赛事,作为培养学生动手能力、解决问题能力、创新能力和实践能力行之有效的途径,受到国内高校的广泛关注。本文以全国大学生化工设计竞赛为契机,结合化工原理课程教学的实际情况,从课堂教学模块化设计和课程教学实践化设计两方面探讨了"化工原理"课程的教学改革。

关键词：化工设计竞赛化工原理教学改革