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An integration method based on a novel combined flow for aerodynamic configuration of strutjet engine

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Chinese Journal of Aeronautics 2021年第9期34卷 156-167页

作者： Longsheng XUE chuan cheng chengpeng WANG Keming cheng College of Aerospace Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016China Key Laboratory of Unsteady Aerodynamics and Flow Control Ministry of Industry and Information TechnologyNanjing University of Aeronautics and AstronauticsNanjing 210016China Aerospace System Engineering Shanghai Shanghai 201100China

In this paper a novel design method of aerodynamic configuration is proposed to integrate forebody,strut and inlet for strutjet engine,and a model at design point of Mach number6 is generated to investigate the aerodynamic performance by both simulations and experiments.The basic flow field employed by proposed method is a combined flow named IBB,which is combined by Internal Conical Flow A(ICFA),truncated Busemann flow I(BI)for external section,and truncated Busemann flow II(BII)for internal section.The model configuration is generated by streamline tracing method from basic flow field,in which the forebody section is traced from ICFA and BI flows,and the inlet as well as strut section is traced from BII flow.The simulations in Mach number 4,5,and 6 demonstrate uniform starting flow fields with relatively high total pressure recovery,which agree well with experiments in wind tunnel.Additionally,in low Mach number cases,this inlet could start at Mach number 3 while it is unstarted at Mach number 2.7;in high Mach number cases,a uniform flow could still exist in Mach number 6.5 while a relatively strong shock wave boundary layer interaction is found in cowl area of Mach number 7 case,indicating the inlet designed by proposed method works in a relatively wide Mach number range.

关键词： Airframe-propulsion integration Busemann flow Combined flow Hypersonics Wind tunnel test

复杂工况下选择性催化还原脱硝系统的迁移强化学习控制

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控制理论与应用 2024年第3期41卷 496-501页

作者：孙小明彭晨程传良上海大学机电工程与自动化学院上海200444

针对复杂工况下选择性催化还原(SCR)系统难以实现精确脱硝控制的问题,本文提出一种基于迁移强化学习的智能控制方法.首先根据机组负荷的变化将整体运行过程划分为不同阶段.然后训练了强化学习控制器以分别学习各个阶段的不同特征,从而... 详细信息

针对复杂工况下选择性催化还原(SCR)系统难以实现精确脱硝控制的问题,本文提出一种基于迁移强化学习的智能控制方法.首先根据机组负荷的变化将整体运行过程划分为不同阶段.然后训练了强化学习控制器以分别学习各个阶段的不同特征,从而实现了变工况下SCR脱硝系统的精确控制.此外,借鉴了迁移学习的思路以应对预料之外的未知工况,避免了因工况未知所造成的不利影响.最后将训练好的控制器用于实际SCR脱硝系统的控制中,实验结果表明所提方法可以有效地控制复杂工况下燃煤机组NOx的排放量,为复杂工况下SCR脱硝系统的智能控制提供了借鉴.

关键词： SCR脱硝系统变工况未知工况强化学习迁移学习

Transformation toughening of Al_2O_3/ZrO_2 laminated ceramics with residual compressive stress

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Journal of University of Science and Technology Beijing 2007年第5期14卷 449-453页

作者： Bei Chen chuan cheng Lan Xiong Li-Ao Wang Key Lab of High Voltage Engineering and Electrical New Technology Chongqing University Chongqing 400044 China Institute of Resource and Environment Science Chongqing University Chongqing 400044 China

With the help of scanning electronic microscopy and X-ray diffraction, the relationships of microstructure characteristics, phase assemblage, and fracture micrograph of Al2O3/ZrO2 laminated ceramics were studied. Compared with monolithic Al2O3/ZrO2 ceramics, the existence of surface compressive stresses greatly restrained the growth of ZrO2 and Al2O3 grains at high sinter temperature, fined the grain size, and increased the content of metastable t-ZrO2, which made the fracture transformation energy quantity 70% higher than that of the monolithic ceramics. The trans-granular and inter-granular fracture features were observed in the surface and center layers, which further verified that transformation toughening is the main mechanism, whereas, micro-crack toughening is helpful for enhancing fracture toughness.

关键词： laminated ceramics transformation toughening fracture micrograph grain size surface compressive stress

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历史事件之可能性研究

玉林师范学院学报 2024年第1期45卷 93-98页

作者：程传利玉林师范学院教育科学学院广西玉林537000

历史研究中有“历史不允许假设”的主张,该主张有其合理性,但是历史研究中也允许假设,允许对本该发生而未发生的事件进行合理的假设和推演。对历史事件的假设及可能性研究,不仅不妨碍史学作为一门科学的影响力,反而增加史学研究的内涵... 详细信息

历史研究中有“历史不允许假设”的主张,该主张有其合理性,但是历史研究中也允许假设,允许对本该发生而未发生的事件进行合理的假设和推演。对历史事件的假设及可能性研究,不仅不妨碍史学作为一门科学的影响力,反而增加史学研究的内涵和价值,有助于人们真正看到历史发展的整体,提高把握历史和运用历史的高度。

关键词：历史认识可能性客观全面性

Analysis of the Current Situation and Risk Factors of Lower Respiratory Tract Infection among ICU Patients in Guizhou,China During 2019-2022

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Journal of Clinical and Nursing Research 2024年第2期8卷 76-85页

作者： Rong Liu Hui Zeng Jing Zhou Lorna K.P.Suen Min-jiang Qian Jie Wan Sheng-shuang Long Lu-wen Luo chuan-li cheng Na-na Yang The Second Affiliated Hospital of Zunyi Medical University Zunyi 563000China School of Nursing The Hong Kong Polytechnic UniversityHong Kong Special Administrative RegionChina School of Nursing The Zunyi Medical UniversityZunyi 563003China

Objective:This study aims to explore the prevalence,features,and risk factors of lower respiratory tract infections(LRTIs)in the intensive care unit(ICU)of a newly established hospital in Zunyi City.The goal is to devise strategies for preventing LRTIs in the ICU of new hospitals,thereby mitigating the incidence of nosocomial LRTIs in ICU patients.Methods:A case-control study was conducted from March 2019 to December 2022 to investigate the incidence rate of LRTIs in the ICU of a newly constructed hospital in Zunyi City.Patients with LRTIs constituted the case group,while those without LRTIs constituted the control group,where a 1:1 matching principle was adhered to.A single-factor chi-square(χ2)test was employed to analyze the risk factors,with independent risk factors being explored using a multivariate logistic regression analysis.Results:A total of 169 strains of pathogenic bacteria were isolated,comprising 66.28%gram-negative bacteria,17.75%gram-positive bacteria,and 15.97%fungi.The most prevalent pathogens included Acinetobacter baumannii(43.20%),Candida albicans(10.65%),and Pseudomonas aeruginosa(8.88%).Of the 82 strains infected by multidrug-resistant bacteria in patients with LRTIs,81.7%were carbapenem-resistant Acinetobacter baumannii,9.8%were multidrug-resistant Pseudomonas aeruginosa,and 6.1%were carbapenem-resistant Escherichia coli.Identified risk factors included smoking history,total hospitalization days,ICU stay length,hypoproteinemia,indwelling gastric tube,intubation type,duration of mechanical ventilation,usage of antibacterial drugs,and administration of protein drugs(P<0.05).Multivariate logistic regression analysis demonstrated that these factors were independent risk factors for nosocomial LRTIs in ICU patients(P<0.05).Conclusion:ICU patients in our hospital were mainly infected by carbapenem-resistant Acinetobacter baumannii.To prevent LRTIs in patients,tailored preventive measures should be developed and the rational use of antibacterial drugs should be promoted.

关键词： Lower respiratory tract infection Risk factors New hospital Intensive care unit

2023年甘肃积石山6.2级地震青海灾区地震地质灾害初步调查分析

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地震 2024年第1期44卷 216-225页

作者：杨传成李智敏熊仁伟盖海龙山东省震灾风险防治中心山东济南有250014 青海省震灾风险防治中心青海西宁810000 中国地震局地震预测研究所北京100036

北京时间2023年12月18日23时59分,甘肃省积石山县(35.70°N, 102.79°E)发生6.2级地震,积石山县大河家镇为本次地震的宏观震中,地震烈度为Ⅷ度(8度)。通过2023年12月18日甘肃积石山MS6.2地震青海地区的现场初步调查发现,这次地震造成大... 详细信息

北京时间2023年12月18日23时59分,甘肃省积石山县(35.70°N, 102.79°E)发生6.2级地震,积石山县大河家镇为本次地震的宏观震中,地震烈度为Ⅷ度(8度)。通过2023年12月18日甘肃积石山MS6.2地震青海地区的现场初步调查发现,这次地震造成大量房屋倒塌,多处出现滑坡、地裂缝和喷砂冒水(液化)现象。由于震区浅表土质松软,地下含水较多,地震的破裂和构造作用造成浅表地体的流滑。本文简要介绍了本次地震的烈度分布、地震地质灾害类型及特点,分析讨论总结此次地震灾害的特征及影响。本研究可为地质灾害重点防范区范围划定、趋势预测和灾后重建提供科学参考,对今后抗震设防和防震减灾工作有启示作用。

关键词： 2023年积石山6.2级地震青海地区地质灾害流滑

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星舰-超重体系与开发的范式变革探究

上海航天（中英文） 2024年第3期41卷 87-94页

作者：吴佳林盛英华程川张众上海航天技术研究院上海201109 上海宇航系统工程研究所上海201109

为了梳理和分析星舰-超重体系与开发的模式,及其相比以往航天运输体系的变革,本文首先回顾星舰-超重的宏观演化与微观验证历程,而后评估基于星舰-超重的太空新物流体系优势与挑战,最后探讨资本驱动下航天运输系统价值网升维与开发范式... 详细信息

为了梳理和分析星舰-超重体系与开发的模式,及其相比以往航天运输体系的变革,本文首先回顾星舰-超重的宏观演化与微观验证历程,而后评估基于星舰-超重的太空新物流体系优势与挑战,最后探讨资本驱动下航天运输系统价值网升维与开发范式变革的内在逻辑。研究发现:星舰-超重的开发理念是“创新引领,市场运作;宏观演化,微观验证”,本质是资本内在增值需求推动新技术、新平台的快速集成和应用。

关键词：星舰-超重太空物流体系开发范式变革水平减速与垂直起降

“课程思政”视角下“汉维翻译理论与实践”课程的教学探究

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喀什大学学报 2024年第1期45卷 106-112页

作者：胡传成张琦喀什大学人文学院新疆喀什844000

运用文献研究法基于“课程思政”视角梳理了“汉维翻译理论与实践”课程教学中存在的问题,认为:翻译理论教学中存在本土理论教学薄弱、不够重视翻译史教学、对各种译论溯源不足等问题;翻译实践教学中存在教学方法单一、翻译实践材料选... 详细信息

运用文献研究法基于“课程思政”视角梳理了“汉维翻译理论与实践”课程教学中存在的问题,认为:翻译理论教学中存在本土理论教学薄弱、不够重视翻译史教学、对各种译论溯源不足等问题;翻译实践教学中存在教学方法单一、翻译实践材料选取随意等问题。在此基础上,针对性提出了策略:翻译理论教学方面要加强本土理论教学,加强翻译史教学,对各种译论进行隐喻和溯源;翻译实践教学方面要注重教学方法多样化、优化翻译实践材料选择,以实现“汉维翻译理论与实践”课程的专业能力和“课程思政润物细无声”的效果双收的教学目的。

关键词：课程思政汉维翻译实践课程教学

Idiopathic colopleural fistula presenting with lung abscess and refractory empyema:A case report

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World Journal of Gastrointestinal Surgery 2023年第4期15卷 740-744页

作者： Chun-Li Wang Kung-chuan cheng Division of Colorectal Surgery Department of SurgeryKaohsiung Chang Gung Memorial HospitalKaohsiung 833Taiwan

BACKGROUND Colopleural fistula is a rare condition,and only a limited number of cases have been reported.Here,we report a case of idiopathic colopleural fistula in an adult without any known predisposing factors.The patient presented with a lung abscess and refractory empyema and was successfully treated with surgical resection.CASE SUMMARY A 47-year-old man with a history of lung tuberculosis,which had been completely cured 4 years ago,presented to our emergency department with a productive cough and fever for 3 d.Tracing his history,he had undergone left lower lobe segmentectomy of the left lung due to lung abscess one year ago at another hospital.However,he developed refractory empyema postoperatively despite surgical intervention including decortication and flap reconstruction.After admission,we reviewed his previous medical images and noted a fistula tract between the left pleural cavity and splenic flexure.In addition,according to his medical records,bacterial culture of the thoracic drainage showed growth of Escherichia coli and Bacteroides fragilis.Our lower gastrointestinal series and colonoscopy confirmed the diagnosis of colopleural fistula.The patient underwent a left hemicolectomy,splenectomy,and distal pancreatectomy,and the diaphragm was repaired under our care.No further empyema recurrence was noted during follow-up.CONCLUSION Indicative signs of colopleural fistula include refractory empyema accompanied by the growth of colonic flora in the pleural fluid.

关键词： Colopleural fistula Lung abscess Empyema Colonic flora Case report