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Validation methodology for distribution-based degradation model

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Journal of Systems Engineering and Electronics 2012年第4期23卷 553-559页

作者： Yunxia Chen zhiguo zeng Rui Kang School of Reliability and Systems Engineering Beihang UniversityBeijing 100191E R.China

Distribution-based degradation models （or graphical approach in some literature） occur in a wide range of applications. However, few of existing methods have taken the validation of the built model into consideration. A validation methodology for distribution-based models is proposed in this paper. Since the model can be expressed as consisting of assumptions of model structures and embedded model parameters, the proposed methodology carries out the validation from these two aspects. By using appropriate statistical techniques, the rationality of degradation distributions, suitability of fitted models and validity of degradation models are validated respectively. A new statistical technique based on control limits is also proposed, which can be implemented in the validation of degradation models＇ validity. The case study on degradation modeling of an actual accelerometer shows that the proposed methodology is an effective solution to the validation problem of distribution-based de qradation models.

关键词： degradation model distribution-based degradationmodel graphical method model validation control limits.

A compositional method to model dependent failure behavior based on PoF models

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Chinese Journal of Aeronautics 2017年第5期30卷 1729-1739页

作者： zhiguo zeng Yunxia CHEN Enrico ZIO Rui KANG EDF Foundation Chair on Systems Science and Energetic Challenge CentraleSupelec Universite Paris-Saclay Grande Voie des Vignes 92290 Chatenay-Malabry France School of Reliability and Systems Engineering Beihang University Beijing 100083 China Energy Department Politecnieo di Milano Italy

In this paper, a new method is developed to model dependent failure behavior among failure mechanisms. Unlike the existing methods, the developed method models the root cause of the dependency explicitly, so that a deterministic model, rather than a probabilistic one, can be established. Three steps comprise the developed method. First, physics-of-failure（PoF） models are utilized to model each failure mechanism. Then, interactions among failure mechanisms are modeled as a combination of three basic relations, competition, superposition and coupling. This is the reason why the method is referred to as ＂compositional method＂. Finally, the PoF models and the interaction model are combined to develop a deterministic model of the dependent failure behavior. As a demonstration, the method is applied on an actual spool and the developed failure behavior model is validated by a wear test. The result demonstrates that the compositional method is an effective way to model dependent failure behavior.

关键词： Degradation Dependent failures Multiple dependent competing failure processes Reliability modeling Shock

Application of reliability technologies in civil aviation: Lessons learnt and perspectives

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Chinese Journal of Aeronautics 2019年第1期32卷 143-158页

作者： Enrico ZIO Mengfei FAN zhiguo zeng Rui KANG Chair System Science and the Energy Challenge Fondation Electricité de France (EDF)CentraleSupélecUniversité Paris Saclay Energy Department Politecnico di Milano Sino-French Risk Science and Engineering Lab Beihang University School of Reliability and Systems Engineering Beihang University

We consider reliability engineering in modern civil aviation industry, and the related engineering activities and methods. We consider reliability in a broad sense, referring to other system characteristics that are related to it, like availability, maintainability, safety and durability. We covered the entire lifecycle of the equipment, including reliability requirement identification, reliability analysis and design, verification and validation of reliability requirements(typically involved in the equipment design and development phase), quality assurance(which typically enters in the manufacturing phase), and fault diagnosis and prognosis and maintenance(which are connected to the operation phase). Lessons learnt from reliability engineering practices in civil aviation industry are given, which might serve as reference for reliability managers and engineers, also from other industries with high reliability requirements.

关键词： Civil aviation Commercial aircraft Fault diagnosis and prognosis Human reliability analysis Maintenance Quality control Reliability design Reliability engineering

Measuring reliability under epistemic uncertainty:Review on non-probabilistic reliability metrics

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Chinese Journal of Aeronautics 2016年第3期29卷 571-579页

作者： Kang Rui ZhangQingyuan zeng zhiguo Enrico Zio Li Xiaoyang School of Reliability and Systems Engineering Beihang UniversityBeijing 100083China Energy Department Politecnico di MilanoMilano 20133Italy Chair on Systems Science and Energy Challenge Fondation Electricite'de France(EDF)Centrale SupelecUniversite'Paris-SucluyChatenay-MalabryParis 92290France

In this paper, a systematic review of non-probabilistic reliability metrics is conducted to assist the selection of appropriate reliability metrics to model the influence of epistemic uncertainty. Five frequently used non-probabilistic reliability metrics are critically reviewed, i.e., evidence- theory-based reliability metrics, interval-analysis-based reliability metrics, fuzzy-interval-analysis- based reliability metrics, possibility-theory-based reliability metrics （posbist reliability） and uncertainty-theory-based reliability metrics （belief reliability）. It is pointed out that a qualified reli- ability metric that is able to consider the effect of epistemic uncertainty needs to （ 1 ） compensate the conservatism in the estimations of the component-level reliability metrics caused by epistemic uncertainty, and （2） satisfy the duality axiom, otherwise it might lead to paradoxical and confusing results in engineering applications. The five commonly used non-probabilistic reliability metrics are compared in terms of these two properties, and the comparison can serve as a basis for the selection of the appropriate reliability metrics.

关键词： Belief reliability Epistemic uncertaintyEvidence theory Interval analysis Possibility theory Probability box Reliability metrics Uncertainty theory

融入科学家精神的高校理工科研究生课程思政教学研究——以湖南科技大学为例

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当代教育理论与实践 2024年第5期16卷 122-128页

作者：曾治国匡曼丽唐佳海湖南科技大学继续教育学院湖南湘潭411201 湖南科技大学招生就业处湖南湘潭411201 湖南科技大学马克思主义学院湖南湘潭411201

研究生教育是学历教育的最高层次,理工科研究生课程思政建设直接关系到国家新型技术人才培养质量。党的十八大以来,以习近平同志为核心的党中央高度重视研究生教育,施行一系列新举措推动研究生教育及研究生思想政治教育高质量发展。课... 详细信息

研究生教育是学历教育的最高层次,理工科研究生课程思政建设直接关系到国家新型技术人才培养质量。党的十八大以来,以习近平同志为核心的党中央高度重视研究生教育,施行一系列新举措推动研究生教育及研究生思想政治教育高质量发展。课程思政建设背景下,从思想政治教育意义丰富的科学家精神入手,围绕研究生培养的学科体系、教材体系、教学体系、队伍体系和管理体系五个方面,探讨高校理工科研究生人才培养推进策略具有重要的应用价值。

关键词：课程思政科学家精神理工科研究生人才培养

同方期刊数据库博看期刊评论

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肉类嘌呤含量及降嘌呤方法研究进展

食品与发酵工业 2022年第18期48卷 314-321页

作者：彭松林曾治国张涛尚永彪西南大学食品科学学院重庆400715 丰都县肉牛产业发展服务中心重庆408200 农业部农产品贮藏保鲜质量安全评估实验室(重庆) 重庆400715 重庆市特色食品工程技术研究中心重庆400715

嘌呤是生物体内重要的含氮碱基,在人体内代谢成为尿酸。当人体摄入过多嘌呤或嘌呤代谢紊乱时会导致高血尿酸症,提高痛风发病率,危害人体健康。肉类是人体摄入嘌呤的重要来源,高嘌呤含量的肉类能够显著影响人体内的血尿酸水平。该文就嘌... 详细信息

嘌呤是生物体内重要的含氮碱基,在人体内代谢成为尿酸。当人体摄入过多嘌呤或嘌呤代谢紊乱时会导致高血尿酸症,提高痛风发病率,危害人体健康。肉类是人体摄入嘌呤的重要来源,高嘌呤含量的肉类能够显著影响人体内的血尿酸水平。该文就嘌呤与痛风病的关系、肉类嘌呤前处理方法、检测条件以及部分肉类嘌呤含量及其降嘌呤方法等进行了归纳总结,以期为肉类嘌呤的进一步研究提供参考,也为消费者选择肉类产品以及如何降低肉类嘌呤含量提供科学指导。

关键词：肉类嘌呤检测方法降嘌呤方法高血尿酸症痛风

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畜禽肉类腥味物质检测与去除方法研究进展

食品与发酵工业 2023年第14期49卷 338-345页

作者：刘春节张涛曾治国尚永彪西南大学食品科学学院重庆400715 丰都县肉牛产业发展服务中心重庆408200 川渝共建特色食品重庆市重点实验室重庆400715

畜禽肉是我国动物性食品消费的主要组成部分,包括猪肉、牛肉、羊肉、鸡鸭鹅肉、兔肉等。畜禽肉通常都具有一定的腥味,如果加工不当会影响到产品品质进而影响到消费者对产品的接受程度。此前关于腥味物质的研究主要集中在水产加工领域,... 详细信息

畜禽肉是我国动物性食品消费的主要组成部分,包括猪肉、牛肉、羊肉、鸡鸭鹅肉、兔肉等。畜禽肉通常都具有一定的腥味,如果加工不当会影响到产品品质进而影响到消费者对产品的接受程度。此前关于腥味物质的研究主要集中在水产加工领域,近年来畜禽肉类中腥味物质的研究也越来越受关注。该文综述了不同畜禽肉类腥味物质的主要成分及其含量、腥味物质检测方法及去除方法,以期为后续关于畜禽肉类的研究提供参考,同时为畜禽肉的加工过程中如何降低腥味提供科学指导。

关键词：畜禽肉腥味物质检测方法去腥方法

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陡坡岩石地基抗滑桩有效嵌固深度的确定

应用力学学报 2020年第6期37卷 2489-2495,I0012,I0013页

作者：贺建清曾治国梅松华高文华湖南科技大学岩土工程稳定控制与健康监测省重点实验室湘潭411201 水能资源利用关键技术湖南省重点实验室长沙410014 中国电建集团中南勘测设计研究院有限公司长沙410014

对桩前楔体进行受力分析,建立极限平衡方程,求解极值并确定楔体破裂角,进而提出楔体临界深度的计算方法。通过工程实例验证了该计算方法的可行性,并分析了陡坡岩石地基坡角、地基岩体抗剪强度指标(黏聚力、内摩擦角)、楔体自重、桩宽、... 详细信息

对桩前楔体进行受力分析,建立极限平衡方程,求解极值并确定楔体破裂角,进而提出楔体临界深度的计算方法。通过工程实例验证了该计算方法的可行性,并分析了陡坡岩石地基坡角、地基岩体抗剪强度指标(黏聚力、内摩擦角)、楔体自重、桩宽、岩体压力扩散角对桩前楔体破裂角及临界深度的影响。研究发现:陡坡岩石地基坡角、地基岩体的抗剪强度指标(黏聚力、内摩擦角)、楔体自重对桩前楔体破裂角及临界深度均有较大影响;桩宽、岩体压力扩散角对桩前楔体临界深度有一定影响,但对其破裂角的影响不大。本文研究成果对确定抗滑桩的有效嵌固深度,指导陡坡岩石地基抗滑桩的设计和施工具有重要的工程意义。

关键词：陡坡抗滑桩嵌固深度楔体破裂角临界深度

板坯连铸结晶器凝固前沿钢液速度、温度和硫含量变化规律

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钢铁研究学报 2024年第3期36卷 340-347页

作者：胡增罗志国邹宗树东北大学冶金学院多金属共生矿生态化冶金教育部重点实验室辽宁沈阳110819

板坯连铸结晶器凝固前沿钢液存在较大的速度梯度、温度梯度及硫浓度梯度,对凝固坯壳捕获气泡及夹杂物有很大影响。采用ANSYS Fluent对板坯连铸结晶器内不同高度处窄面凝固前沿的钢液速度、温度及硫含量分布进行研究。距结晶器自由液面0.... 详细信息

板坯连铸结晶器凝固前沿钢液存在较大的速度梯度、温度梯度及硫浓度梯度,对凝固坯壳捕获气泡及夹杂物有很大影响。采用ANSYS Fluent对板坯连铸结晶器内不同高度处窄面凝固前沿的钢液速度、温度及硫含量分布进行研究。距结晶器自由液面0.1、0.3、0.6 m的截面上平行于X方向位于结晶器中心处的3条截线分别代表结晶器窄面凝固前沿的上部区域、冲击区域和下部区域,对每条线上距凝固前沿3 mm处钢液X方向的速度梯度、温度梯度及硫含量梯度进行计算分析。结果表明:下部区域钢液的速度梯度最大(14.5 s^(-1)),略大于上部区域(14.1 s^(-1)),冲击区域则最小(0.4 s^(-1));下部区域钢液的温度梯度最大(902.3 K/m),约为上部区域的2.0倍,冲击区域的2.4倍;上部区域硫含量梯度最大(0.42%/m),下部区域次之(0.04%/m),冲击区域最小(0.02%/m)。在3个区域中,随着与凝固前沿距离的增大,钢液中的硫含量分布存在2种变化形式:先增大后减小至初始含量值;先减小再增大最后减小至初始含量值。

关键词：连铸结晶器凝固前沿温度场硫含量分布