Blade rubbing faults cause detrimental impact on the operation of aeroengines. Most of the existing studies on blade rubbing in the shaft-disk-blade-casing(SDBC) system have overlooked the elastic deformation of the b...Blade rubbing faults cause detrimental impact on the operation of aeroengines. Most of the existing studies on blade rubbing in the shaft-disk-blade-casing(SDBC) system have overlooked the elastic deformation of the blade, while some only consider the whirl of the rotor, neglecting its spin. To address these limitations, this paper proposes a dynamic model with large rotation for the SDBC system. The model incorporates the spin and whirl of the rotor, enabling the realistic reproduction of multiblade rubbing faults. To verify the accuracy of the SDBC model with large rotation and demonstrate its capability to effectively consider the rotational effects such as the centrifugal stiffening and gyroscopic effects, the natural characteristics and dynamic responses of the proposed model are compared with those obtained from reported research and experimental results. Furthermore, the effects of the rotating speed, contact stiffness,and blade number on the dynamic characteristics of the SDBC system with multi-blade rubbing are investigated. The results indicate that the phase angle between the rotor deflection and the unbalance excitation force increases with the increasing rotating speed,which significantly influences the rubbing penetration of each blade. The natural frequency of the SDBC system with rubbing constrain can be observed in the acceleration response of the casing and the torsional response of the shaft, and the frequency is related to the contact stiffness. Moreover, the vibration amplitude increases significantly with the product of the blade number under rubbing, and the rotating frequency approaches the natural frequency of the SDBC system. The proposed model can provide valuable insight for the fault diagnosis of rubbing in bladed rotating machinery.展开更多
目的:探讨多学科围术期疼痛干预对胸腔镜肺叶切除术(VATS)术后疼痛、术后恢复和并发症的影响。方法:选取施行VATS治疗的116例患者为研究对象。依据干预方式不同将116例VATS患者分为对照组和观察组,每组各58例。对照组实施常规疼痛干预;...目的:探讨多学科围术期疼痛干预对胸腔镜肺叶切除术(VATS)术后疼痛、术后恢复和并发症的影响。方法:选取施行VATS治疗的116例患者为研究对象。依据干预方式不同将116例VATS患者分为对照组和观察组,每组各58例。对照组实施常规疼痛干预;观察组实施多学科围术期疼痛干预。比较两组疼痛情况[数字疼痛评分法(NRS)]、术后恢复情况、术后康复质量[Quality of Recovery-15,QoR-15]及并发症发生情况。结果:术后24 h及术后72 h观察组静息及咳嗽时NRS评分均低于对照组(P<0.05)。观察组术后首次下床活动时间、首次排气时间、首次经口进食时间及术后住院时间均短于对照组(P<0.05)。术后72 h,两组QoR-15评分均高于术后24 h(P<0.05),且观察组术后24、72 h QoR-15评分均高于对照组(P<0.05)。观察组总并发症发生率低于对照组(8.61%vs.22.41%,P<0.05)。结论:多学科围术期疼痛干预可降低VATS术后疼痛,促进术后恢复进程,提升康复质量,并能在一定程度上减少并发症发生。展开更多
To implement the computation of AHP (Analytic Hierarchy Process) automatically, make the implementation inde-pendence on the platform, and to convenient the service composi-tion and service computation, this study imp...To implement the computation of AHP (Analytic Hierarchy Process) automatically, make the implementation inde-pendence on the platform, and to convenient the service composi-tion and service computation, this study implemented AHP model as a Web service and stored the evaluation information as XML form. This paper introduces the overall demands of AHP evalua-tion system firstly, and then presents some key technologies to implement AHP evaluation system, including mainly AHP evalua-tion index architecture based on XML, the class of AHP model, the Web service encapsulation of AHP, the publication and invoca-tion of AHP and the client application. At last, the system is used to analyze the impact factors of online consumption behavior.展开更多
为提升水产品危害分析及关键控制点(Hazard analysis and critical control points,HACCP)体系国家标准在保障质量溯源方面的数据可信、可读,以国家标准中的巴氏杀菌蟹肉HACCP计划为例,结合语义建模和区块链技术,提出了巴氏杀菌蟹肉增强...为提升水产品危害分析及关键控制点(Hazard analysis and critical control points,HACCP)体系国家标准在保障质量溯源方面的数据可信、可读,以国家标准中的巴氏杀菌蟹肉HACCP计划为例,结合语义建模和区块链技术,提出了巴氏杀菌蟹肉增强HACCP计划可信可视溯源模型(Enhanced HACCP credibility and visualization traceability model,EHCVTM)。该模型结合国家标准对巴氏杀菌蟹肉HACCP计划进行语义理解,构建巴氏杀菌蟹肉HACCP计划质量安全数据体系(HACCP quality and safety data system,HQSDS)并设计知识表示。为所得的增强HACCP计划的执行数据设计合理的数据存储结构、智能合约,实现“有风险上链,无风险自治”、“高风险直接上链,低风险加密上链”的数据分级存储管理模式。然后借助图数据库实现不同需求的可视化展示。最终实现了基于EHCVTM的HACCP质量溯源应用原型并进行测试。结果表明,基于此模型的应用保障了质量溯源风险数据的可信度,提高了数据反馈时的可读性,增强了质量溯源平台预警能力,使企业内部完成精细化监控,企业外部多方监督,质量安全风险公开,安全责任定位精确。且基于区块链的系统吞吐量达到300笔/s,可基本满足溯源系统的业务需求。该研究为基于HACCP国家标准的水产品质量安全风险监控可信可视溯源提供了新思路。展开更多
目的:评估BRCA1/2基因突变状态与卵巢癌患者临床特征的相关性及对预后的影响。方法:选取2017年11月—2022年6月在兰州大学第一医院进行治疗的51例接受BRCA1/2基因检测的卵巢癌患者作为研究对象,根据检测结果分为BRCA1/2突变组(30例)和BR...目的:评估BRCA1/2基因突变状态与卵巢癌患者临床特征的相关性及对预后的影响。方法:选取2017年11月—2022年6月在兰州大学第一医院进行治疗的51例接受BRCA1/2基因检测的卵巢癌患者作为研究对象,根据检测结果分为BRCA1/2突变组(30例)和BRCA1/2正常组(21例)。比较2组患者的临床基线资料、临床病理特征和预后,分析影响BRCA1/2基因突变的卵巢癌患者预后的相关因素。结果:BRCA1/2突变组与BRCA1/2正常组相比,发病年龄、体质量指数(body mass index,BMI)、恶性肿瘤家族史、治疗前糖类抗原125(carbohydrate antigen 125,CA125)及人附睾蛋白4(human epididymis protein 4,HE4)差异均无统计学意义(均P>0.05)。BRCA1/2突变组与BRCA1/2正常组肿瘤分期及淋巴结转移情况比较,差异有统计学意义(P<0.05)。多因素Cox回归分析显示BRCA1/2基因突变不是卵巢癌生存率及无进展生存期的独立预后因素(HR=0.752,95%CI:0.394~1.435,P=0.329)。结论:BRCA1/2基因突变是决定卵巢癌患者临床治疗的重要因素,与肿瘤分期及淋巴结转移情况显著相关,但仍不能确定BRCA1/2基因突变是卵巢癌的独立危险因素。展开更多
基金Project supported by the National Science and Technology Major Project of China (No. 2017-V-0009)the National Natural Science Foundation of China (Nos. 12032015 and 12121002)the National Funding Program for Postdoctoral Researchers of China (No. GZC20231586)。
文摘Blade rubbing faults cause detrimental impact on the operation of aeroengines. Most of the existing studies on blade rubbing in the shaft-disk-blade-casing(SDBC) system have overlooked the elastic deformation of the blade, while some only consider the whirl of the rotor, neglecting its spin. To address these limitations, this paper proposes a dynamic model with large rotation for the SDBC system. The model incorporates the spin and whirl of the rotor, enabling the realistic reproduction of multiblade rubbing faults. To verify the accuracy of the SDBC model with large rotation and demonstrate its capability to effectively consider the rotational effects such as the centrifugal stiffening and gyroscopic effects, the natural characteristics and dynamic responses of the proposed model are compared with those obtained from reported research and experimental results. Furthermore, the effects of the rotating speed, contact stiffness,and blade number on the dynamic characteristics of the SDBC system with multi-blade rubbing are investigated. The results indicate that the phase angle between the rotor deflection and the unbalance excitation force increases with the increasing rotating speed,which significantly influences the rubbing penetration of each blade. The natural frequency of the SDBC system with rubbing constrain can be observed in the acceleration response of the casing and the torsional response of the shaft, and the frequency is related to the contact stiffness. Moreover, the vibration amplitude increases significantly with the product of the blade number under rubbing, and the rotating frequency approaches the natural frequency of the SDBC system. The proposed model can provide valuable insight for the fault diagnosis of rubbing in bladed rotating machinery.
文摘目的:探讨多学科围术期疼痛干预对胸腔镜肺叶切除术(VATS)术后疼痛、术后恢复和并发症的影响。方法:选取施行VATS治疗的116例患者为研究对象。依据干预方式不同将116例VATS患者分为对照组和观察组,每组各58例。对照组实施常规疼痛干预;观察组实施多学科围术期疼痛干预。比较两组疼痛情况[数字疼痛评分法(NRS)]、术后恢复情况、术后康复质量[Quality of Recovery-15,QoR-15]及并发症发生情况。结果:术后24 h及术后72 h观察组静息及咳嗽时NRS评分均低于对照组(P<0.05)。观察组术后首次下床活动时间、首次排气时间、首次经口进食时间及术后住院时间均短于对照组(P<0.05)。术后72 h,两组QoR-15评分均高于术后24 h(P<0.05),且观察组术后24、72 h QoR-15评分均高于对照组(P<0.05)。观察组总并发症发生率低于对照组(8.61%vs.22.41%,P<0.05)。结论:多学科围术期疼痛干预可降低VATS术后疼痛,促进术后恢复进程,提升康复质量,并能在一定程度上减少并发症发生。
基金the National Natural Science Foundation of China(70772073)the Natural Science Foundation of Shanghai (07ZR14003)+1 种基金the Social Science Programming Foundation of Shanghai(2007BZH001)Excellent Young Teachers Follow-Up Scientific Research Foundation of Shanghai Fisheries University(A-0212-07-0132)
文摘To implement the computation of AHP (Analytic Hierarchy Process) automatically, make the implementation inde-pendence on the platform, and to convenient the service composi-tion and service computation, this study implemented AHP model as a Web service and stored the evaluation information as XML form. This paper introduces the overall demands of AHP evalua-tion system firstly, and then presents some key technologies to implement AHP evaluation system, including mainly AHP evalua-tion index architecture based on XML, the class of AHP model, the Web service encapsulation of AHP, the publication and invoca-tion of AHP and the client application. At last, the system is used to analyze the impact factors of online consumption behavior.
文摘为提升水产品危害分析及关键控制点(Hazard analysis and critical control points,HACCP)体系国家标准在保障质量溯源方面的数据可信、可读,以国家标准中的巴氏杀菌蟹肉HACCP计划为例,结合语义建模和区块链技术,提出了巴氏杀菌蟹肉增强HACCP计划可信可视溯源模型(Enhanced HACCP credibility and visualization traceability model,EHCVTM)。该模型结合国家标准对巴氏杀菌蟹肉HACCP计划进行语义理解,构建巴氏杀菌蟹肉HACCP计划质量安全数据体系(HACCP quality and safety data system,HQSDS)并设计知识表示。为所得的增强HACCP计划的执行数据设计合理的数据存储结构、智能合约,实现“有风险上链,无风险自治”、“高风险直接上链,低风险加密上链”的数据分级存储管理模式。然后借助图数据库实现不同需求的可视化展示。最终实现了基于EHCVTM的HACCP质量溯源应用原型并进行测试。结果表明,基于此模型的应用保障了质量溯源风险数据的可信度,提高了数据反馈时的可读性,增强了质量溯源平台预警能力,使企业内部完成精细化监控,企业外部多方监督,质量安全风险公开,安全责任定位精确。且基于区块链的系统吞吐量达到300笔/s,可基本满足溯源系统的业务需求。该研究为基于HACCP国家标准的水产品质量安全风险监控可信可视溯源提供了新思路。
文摘目的:评估BRCA1/2基因突变状态与卵巢癌患者临床特征的相关性及对预后的影响。方法:选取2017年11月—2022年6月在兰州大学第一医院进行治疗的51例接受BRCA1/2基因检测的卵巢癌患者作为研究对象,根据检测结果分为BRCA1/2突变组(30例)和BRCA1/2正常组(21例)。比较2组患者的临床基线资料、临床病理特征和预后,分析影响BRCA1/2基因突变的卵巢癌患者预后的相关因素。结果:BRCA1/2突变组与BRCA1/2正常组相比,发病年龄、体质量指数(body mass index,BMI)、恶性肿瘤家族史、治疗前糖类抗原125(carbohydrate antigen 125,CA125)及人附睾蛋白4(human epididymis protein 4,HE4)差异均无统计学意义(均P>0.05)。BRCA1/2突变组与BRCA1/2正常组肿瘤分期及淋巴结转移情况比较,差异有统计学意义(P<0.05)。多因素Cox回归分析显示BRCA1/2基因突变不是卵巢癌生存率及无进展生存期的独立预后因素(HR=0.752,95%CI:0.394~1.435,P=0.329)。结论:BRCA1/2基因突变是决定卵巢癌患者临床治疗的重要因素,与肿瘤分期及淋巴结转移情况显著相关,但仍不能确定BRCA1/2基因突变是卵巢癌的独立危险因素。
