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Transportation Safety and Environment 2021年第2期3卷 114-122页

作者： Xianku Zhang baigang Zhao Guoqing Zhang Navigation College Dalian Maritime UniversityDalian 116026China

This paper investigates the problem of parameter identification for ship nonlinear Nomoto model with small test data,a nonlinear innovation-based identification algorithm is presented by embedding sigmoid function in the stochastic gradient *** demonstrate the validity of the algorithm,an identification test is carried out on the ship‘SWAN’with only 26 sets of test ***,the identification effects of the least squares algorithm,original stochastic gradient algorithm and the improved stochastic gradient algorithm based on nonlinear innovation are ***,the stochastic gradient algorithm is not suitable for the condition of small test *** simulation results indicate that the improved stochastic gradient algorithm with sigmoid function greatly increases its accuracy of parameter identification and has 14.2%up compared with the least squares *** the effectiveness of the algorithm is verified by another identification test on the ship‘Galaxy’,the accuracy of parameter identification can reach more than 95%which can be used in ship motion simulation and controller *** proposed algorithm has advantages of the small test data,fast speed and high accuracy of identification,which can be extended to other parameter identification systems with less sample data.

关键词： ship model parameter identification nonlinear innovation sigmoid function stochastic gradient

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重视动物致伤的防治工作

临床急诊杂志 2024年第8期25卷 410-412,419页

作者：闫柏刚蒋杰孙春红重庆医科大学附属第三医院急诊与重症医学中心重庆401120

随着人被各种动物致伤的事件逐年增多,动物致伤已成为重要的公共卫生问题。除了对人体组织器官的直接损伤,动物自身拥有对人体有毒物质导致的中毒(如毒蛇咬伤出现的神经毒和血液毒等)、动物携带的病原微生物由攻击伤口进入人体导致的普... 详细信息

随着人被各种动物致伤的事件逐年增多,动物致伤已成为重要的公共卫生问题。除了对人体组织器官的直接损伤,动物自身拥有对人体有毒物质导致的中毒(如毒蛇咬伤出现的神经毒和血液毒等)、动物携带的病原微生物由攻击伤口进入人体导致的普通感染性和特殊感染性疾病,是动物致伤研究的要点。受益于我国狂犬病防治系统的建立,为推动实现“到2030年犬类传播狂犬病零人类死亡”目标,今后要更加重视动物致伤领域的基础与临床研究,探讨如何更好地做好预防与医疗的结合,做好各级预防处置门诊的规范化,更好地应对动物致伤带来的种种问题。

关键词：动物致伤中毒特殊感染防治策略医防结合

动物致伤患者伤口感染危险因素分析及预测模型的建立

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临床急诊杂志 2024年第8期25卷 424-427页

作者：孙春红李勇闫柏刚重庆医科大学附属第三医院急诊与重症医学中心重庆401120

目的:分析动物致伤患者伤口感染的危险因素,并构建预测模型。方法:回顾性收集2020年10月—2022年12月收治的649例动物致伤患者临床资料,根据患者是否发生创面感染分为感染组和未感染组,分析动物致伤患者伤口感染的影响因素,并构建回归方... 详细信息

目的:分析动物致伤患者伤口感染的危险因素,并构建预测模型。方法:回顾性收集2020年10月—2022年12月收治的649例动物致伤患者临床资料,根据患者是否发生创面感染分为感染组和未感染组,分析动物致伤患者伤口感染的影响因素,并构建回归方程,采用受试者工作特征曲线(ROC)分析回归方程的预测价值。结果:年龄≥51.5岁、受伤至清创时间≥6.5 h、受伤部位为手足、糖尿病是动物致伤患者伤口感染的独立危险因素,根据多因素分析结果构建回归方程及预测概率绘制ROC曲线,当Logit(P)>0.2043时,AUC为0.930(95%CI:0.897~0.964),约登指数为0.759,灵敏度为86.0%,特异度为89.9%。结论:动物致伤患者伤口感染的独立危险因素包括年龄≥51.5岁、受伤至清创时间≥6.5 h、受伤部位为手足、糖尿病,相关回归方程对动物致伤患者伤口感染的预测价值较好,为动物致伤患者伤口感染高危因素进行个体化评估治疗提供了依据。

关键词：动物致伤伤口感染危险因素预测模型

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SPA-H钢低氧出钢的生产技术实践

冶金能源 2024年第1期43卷 14-18,32页

作者：李超于海岐刘博崔福祥金百刚苏小利鞍钢股份有限公司鲅鱼圈钢铁分公司炼钢部

针对生产SPA-H钢冶炼中低氧控制出钢技术开展研究,分析了相关热力学理论及低氧出钢必要性,确定了SPA-H钢合理低氧范围应为(198~333)×10^(-6)。为实现低氧控制开展了技术改进,合理控制转炉终渣成分,合理排产,实行灵活的溅渣护炉措施;改... 详细信息

针对生产SPA-H钢冶炼中低氧控制出钢技术开展研究,分析了相关热力学理论及低氧出钢必要性,确定了SPA-H钢合理低氧范围应为(198~333)×10^(-6)。为实现低氧控制开展了技术改进,合理控制转炉终渣成分,合理排产,实行灵活的溅渣护炉措施;改进冶炼制度,采用“一批料”模式或留少量料模式,改进氧枪工作参数,降低平均枪位,优化枪位控制,保证低枪位拉碳时间,终点温度按照1680℃控制,碳按照0.06%~0.11%控制;采用碳—氧修正模型、转炉质谱仪等辅助手段。改进后,平均终点氧含量降低,氧含量80%控制在选定合理范围,磷、硫、碳及锰含量控制水平均有提升。

关键词： SPA-H 低氧磷含量硫含量碳含量锰含量

Experiment of gas plasma plume deflection by magnetic control

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航空动力学报 2020年第3期35卷 581-588页

作者： ZHAO Kai HU Jianbo LU Yongji LI Feng MING Ming SUN baigang School of Energy and Power Engineering Beijing University of Aeronautics and AstronauticsBeijing 100191China School of Aviation Operations and Services Aviation University of Air ForceChangchun Jilin 130022China Department of Contract Tactics Air Force Command CollegeBeijing 100097China

To investigate the deflection effect of gas plasma plume controlled by magnetic field,a novel experimental scheme was *** Cs2CO3 catalytic ionization seeds were injected into the combustion chamber to obtain gas plasma on a high temperature magneto hydrodynamic(MHD)experiment *** plasma jet was deflected under the action of an external magnetic field,resulting in a thrust-vector *** image velocimetry(PIV)collected two-dimensional images of jet flow *** image processing and velocity vector analysis,the jet deflection angle can be obtained *** 1800-2500 K,the jet deflection was verified experimentally under the condition of 0.45 T magnetic field *** results indicate that the jet deflection angle increases gradually with the increase of gas temperature,and above 2200 K,the jet deflection angle increase *** the process of gas plasma jet,it is feasible to realize the jet deflection controlled by MHD by adding an external magnetic field.

关键词： gas plasma plume deflection magnetic fluid thrust vector particle image velocimetry

Destruction of 4-phenolsulfonic acid in water by anodic contact glow discharge electrolysis

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Journal of Environmental Sciences 2013年第6期25卷 1063-1070页

作者： Haiming Yang baigang an Shaoyan Wang Lixiang Li Wenjie Jin Lihua Li School of Chemical Engineering University of Science and Technology Liaoning

Destruction of 4-phenolsulfonic acid （4-PSA） in water was carded out using anodic contact glow discharge electrolysis. Accompanying the decay of 4-PSA, the amount of total organic carbon （TOC） in water correspondingly decreased, while the sulfonate group of 4- PSA was released as sulfate ion. Oxalate and formate were obtained as minor by-products. Additionally, phenol, 1,4-hydroquinone, hydroxyquinol and 1,4-benzoquinone were detected as primary intermediates in the initial stages of decomposition of 4-PSA. A reaction pathway involving successive attacks of hydroxyl and hydrogen radicals was assumed on the basis of the observed products and kinetics. It was revealed that the decay of both 4-PSA and TOC obeyed a first-order rate law. The effects of different Fe ions and initial concentrations of 4-PSA on the degradation rate were investigated. It was found that the presence of Fe ions could increase the degradation rate of 4-PSA, while initial concentrations lower than 80 mmol/L had no significant effect on kinetic behaviour. The disappearance rate of 4-PSA was significantly affected by pH.

关键词： 4-phenolsulfonic acid destruction contact glow discharge electrolysis first-order rate law Fenton reaction

基于DS-InSAR的彩北矿区形变监测研究

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山西建筑 2024年第22期50卷 173-177页

作者：王佰刚余力葛子轩吉林省基础测绘院河南省资源环境调查一院有限公司湖南科技大学地球科学与空间信息工程学院

本溪市是我国辽宁省东部的中心城市，矿产资源储备丰富，是我国重要的老工业矿产园区。长时间的矿产资源开采，会极大程度影响采矿区的地质构造，导致采矿区地面形变现象发生。文章选取本溪市彩北矿区作为研究区域，基于Sentinel-1B影... 详细信息

本溪市是我国辽宁省东部的中心城市，矿产资源储备丰富，是我国重要的老工业矿产园区。长时间的矿产资源开采，会极大程度影响采矿区的地质构造，导致采矿区地面形变现象发生。文章选取本溪市彩北矿区作为研究区域，基于Sentinel-1B影像采用DS-InSAR技术开展地面形变监测。监测结果表明，由于长期矿区开采活动，研究区域在2017年依然存在两处明显的地面沉降，最大地面沉降速率可达-28 mm/a,利用时间维度相干系数进行内校检精度评估，结果显示全部DS点形变精度在3 mm以内。

关键词：地面沉降矿区开采 DS-InSAR

Development of performance and combustion system of Atkinson cycle internal combustion engine

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Science China(Technological Sciences) 2014年第3期57卷 471-479页

作者： LIU FuShui SUN baigang ZHU HuaRong HU TieGang DU Wei LI XiangRong ZHANG Zheng School of Mechanical Engineering Beijing Institute of Technology Chang'an Auto Co. Ltd

The application of hybrid vehicle is a practical technical solution to the energy shortage and the environmental *** internal combustion engine(ICE)plays a key role in the development of the hybrid *** on the requirements of the hybrid vehicle and the characteristic of Atkinson cycle,a set of designing methods for the Atkinson cycle gasoline engine is presented through the analysis of the optimized matching for the compression ratio,valve timing and the combustion *** designing method has been verified by the bench test and the results show that the fuel consumption can be improved by12%–15%with the reduction of the low speed torque by 10%,and the low fuel consumption region in the fuel map extends significantly with the rated power almost keeping *** may be of great reference for the development of hybrid vehicle technology in China.

关键词： hybrid vehicle Atkinson cycle compression ratio valve timing combustion chamber

基于改进NSGA-Ⅱ算法的多目标不相关并行机调度研究

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数字制造科学 2024年第1期 38-42页

作者：周嫄杨路达郭钧杜百岗武汉理工大学机电工程学院湖北武汉430070

针对不相关并行机调度问题,考虑不完美维修和完美维修两种预防性维修方式,建立了以最小化最大完工时间和任务总延期时间为目标的调度模型,提出了一种基于变领域搜索的改进多目标遗传算法(INSGA-Ⅱ-VNS)对其进行求解。通过不同数据集的... 详细信息

针对不相关并行机调度问题,考虑不完美维修和完美维修两种预防性维修方式,建立了以最小化最大完工时间和任务总延期时间为目标的调度模型,提出了一种基于变领域搜索的改进多目标遗传算法(INSGA-Ⅱ-VNS)对其进行求解。通过不同数据集的仿真实验及算法对比,验证了所提算法的有效性和可行性。

关键词：不相关并行机调度预防性维修 INSGA-Ⅱ-VNS

Synthesis of an ordered porous carbon with the dual nitrogen-doped interfaces and its ORR catalysis performance

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Chinese Chemical Letters 2021年第1期32卷 140-145页

作者： Hongwei Zhao Yanqiu Zhang Li Lixiang Xin Geng Haiming Yang Weimin Zhou Chengguo Sun baigang an School of Chemical Engineering University of Science and Technology LiaoningAnshan 114051China Key Laboratory of Energy Materials and Electrochemistry Research Liaoning Province Anshan 114051China

Both nitrogen-doping feature and pore structure are critical factors for developing nitrogen-doped carbons based catalysts with a high performance toward oxygen reduction reaction(ORR).Herein,a simple one-step CVD of acetylene and acetonitrile vapor method using silanized SBA-15 as a template has been developed to synthesize an ordered porous carbon(OPC) with dual nitrogen-doped *** optimized sample as prepared with the CVD of 4 h at 750℃ contains two types of ordered mesopores that one type is the ordered cylindrical pores inheriting from the pores of SBA-15 and has a pore width of4.0~5.0 nm,the other type is the ordered quasi-hexagonal pores with a width of 3.0~4.0 nm produced by etching the pore walls of *** two types of pores whose pore walls are built by the nitrogen doped carbon layers resulted by the CVD and thus it actually makes the dual nitrogen-doped interfaced OPC(DN-OPC).Meanwhile,DN-OPC contains a few of micropores and a large SSA of 1430 m~2/*** dualordered pores and dual nitrogen-doped interfaces cannot only facilitate mass transport but also utilize the active sites of DN-OPC for ***,as metal-free ORR catalyst,DN-OPC exhibits a good activity close to commercial Pt/C catalyst,and an excellent durability and methanol tolerance.

关键词： Silanized SBA-15 Nitrogen-doped Dual-ordered pores CVD of acetonitrile Oxygen reduction reaction