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Energy-Efficient Cluster in Wireless Sensor Network Using Life Time Delay Clustering Algorithms
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作者 V.Kumar N.Jayapandian P.Balasubramanie 《Computer Systems Science & Engineering》 SCIE EI 2022年第10期77-86,共10页
Through Wireless Sensor Networks(WSN)formation,industrial and academic communities have seen remarkable development in recent decades.One of the most common techniques to derive the best out of wireless sensor network... Through Wireless Sensor Networks(WSN)formation,industrial and academic communities have seen remarkable development in recent decades.One of the most common techniques to derive the best out of wireless sensor networks is to upgrade the operating group.The most important problem is the arrangement of optimal number of sensor nodes as clusters to discuss clustering method.In this method,new client nodes and dynamic methods are used to determine the optimal number of clusters and cluster heads which are to be better organized and proposed to classify each round.Parameters of effective energy use and the ability to decide the best method of attachments are included.The Problem coverage find change ability network route due to which traffic and delays keep the performance to be very high.A newer version of Gravity Analysis Algorithm(GAA)is used to solve this problem.This proposed new approach GAA is introduced to improve network lifetime,increase system energy efficiency and end delay performance.Simulation results show that modified GAA performance is better than other networks and it has more advanced Life Time Delay Clustering Algorithms-LTDCA protocols.The proposed method provides a set of data collection and increased throughput in wireless sensor networks. 展开更多
关键词 WSNS Gravity analysis algorithm-GAA life time delay clustering algorithms-LTDCA end to end delay energy efficient
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Phase Wise Supply Chain Model of EOQ with Normal Life Time for Queued Customers: A Computational Approach
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作者 Sant Sharan Mishra Prem Prakash Mishra 《American Journal of Operations Research》 2012年第3期296-307,共12页
In this paper, we mainly aim to compute the optimal inventory in the phase wise supply chain for queued customers in the interval of lower and upper bounds with particular life of the items. Important performance meas... In this paper, we mainly aim to compute the optimal inventory in the phase wise supply chain for queued customers in the interval of lower and upper bounds with particular life of the items. Important performance measures such as total optimal cost of the system and total expected delivery have also been computed by applying the dynamic programming and Drichlet theorem. Finally, numerical demonstration and sensitivity analysis have also been presented to gain the better perspective of the model. 展开更多
关键词 Supply Chain Correlation NORMAL life time Dynamic PROGRAMMING
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Modified DS np Chart Using Generalized Multiple Dependent State Sampling under Time Truncated Life Test
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作者 Wimonmas Bamrungsetthapong Pramote Charongrattanasakul 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第3期2471-2495,共25页
This study presents the design of a modified attributed control chart based on a double sampling(DS)np chart applied in combination with generalized multiple dependent state(GMDS)sampling to monitor the mean life of t... This study presents the design of a modified attributed control chart based on a double sampling(DS)np chart applied in combination with generalized multiple dependent state(GMDS)sampling to monitor the mean life of the product based on the time truncated life test employing theWeibull distribution.The control chart developed supports the examination of the mean lifespan variation for a particular product in the process of manufacturing.Three control limit levels are used:the warning control limit,inner control limit,and outer control limit.Together,they enhance the capability for variation detection.A genetic algorithm can be used for optimization during the in-control process,whereby the optimal parameters can be established for the proposed control chart.The control chart performance is assessed using the average run length,while the influence of the model parameters upon the control chart solution is assessed via sensitivity analysis based on an orthogonal experimental design withmultiple linear regression.A comparative study was conducted based on the out-of-control average run length,in which the developed control chart offered greater sensitivity in the detection of process shifts while making use of smaller samples on average than is the case for existing control charts.Finally,to exhibit the utility of the developed control chart,this paper presents its application using simulated data with parameters drawn from the real set of data. 展开更多
关键词 Modified DS np chart generalizedmultiple dependent state sampling time truncated life test Weibull distribution average run length average sample size
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A Method in Mixed Frequency-time domain for Fatigue Life Estimation of Steel Girders of Cable-stayed Bridges Due to Buffeting 被引量:1
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作者 顾明 陈礼忠 项海帆 《应用基础与工程科学学报》 EI CSCD 1998年第4期70-79,共10页
发展了斜拉桥钢主梁抖振疲劳寿命的混合时-频域方法.在本方法中,首先建立了桥面处的风速风向概率密度函数,导出的应力谱因其包括背景分量而不再是窄带谱.据应力谱模拟出了疲劳应力的时间历程,并用雨流计数法统计了其幅值特性.基... 发展了斜拉桥钢主梁抖振疲劳寿命的混合时-频域方法.在本方法中,首先建立了桥面处的风速风向概率密度函数,导出的应力谱因其包括背景分量而不再是窄带谱.据应力谱模拟出了疲劳应力的时间历程,并用雨流计数法统计了其幅值特性.基于修正的Miner定理导出了考虑风速风向作用的桥梁主梁抖振疲劳寿命的估算公式,并用此分析了杨浦大桥钢主梁的抖振疲劳寿命.结果表明,风向对抖振疲劳寿命有很大影响;杨浦大桥主梁的疲劳寿命远大于设计寿命. 展开更多
关键词 斜拉桥 钢主梁 抖振 疲劳寿命 混合时-频域
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基于TimeGAN-GRU的镍镉蓄电池RUL预测 被引量:2
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作者 于天剑 杨雨萌 +3 位作者 刘海涛 伍珣 代毅 向超群 《铁道科学与工程学报》 EI CAS CSCD 北大核心 2024年第12期4899-4909,共11页
镍镉蓄电池广泛用作我国高速列车的辅助电源,其性能可靠性直接关系到高速列车行车安全。蓄电池剩余使用寿命是指其性能从当前状态退化至失效的时长或可充放电次数,是表征电池性能的重要指标。目前,高速列车镉镍蓄电池寿命模型受限于小... 镍镉蓄电池广泛用作我国高速列车的辅助电源,其性能可靠性直接关系到高速列车行车安全。蓄电池剩余使用寿命是指其性能从当前状态退化至失效的时长或可充放电次数,是表征电池性能的重要指标。目前,高速列车镉镍蓄电池寿命模型受限于小样本数据而存在精确性和泛化性差的问题。因此,从全新镍镉蓄电池寿命实验数据中提取电池退化特征,采取时序对抗生成网络对其进行增强从而提高数据规模和质量,并依据分类分数、预测分数、主成分分析、t-分布随机邻域嵌入分析方法对增强效果进行评价。其次,使用增强数据建立门控循环单元方法的高速列车镍镉蓄电池剩余使用寿命预测模型。最终,通过四级修镉镍蓄电池循环寿命实验数据进行不同预测起点验证,并对比时序对抗生成网络-门控循环单元融合模型、门控循环单元模型、长短期记忆模型的预测效果。研究结果表明:对于时序对抗生成网络数据增强效果,真实数据与模拟数据分布相近,平均绝对误差小,模拟数据质量较高;经四级修镍镉蓄电池数据验证的时序对抗生成网络-门控循环单元融合模型相比门控循环单元模型、长短期记忆模型,具有更高的泛化性能和预测精度。针对高速列车镍镉蓄电池在小样本数据限制下建立了具有较好精确性和泛化性的剩余寿命预测模型,为保障高速列车行车安全和优化制定检修方案提供了参考。 展开更多
关键词 蓄电池 镍镉蓄电池 剩余寿命预测 时序对抗生成网络 门控循环单元网络
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A Multi-Hop Dynamic Path-Selection (MHDP) Algorithm for the Augmented Lifetime of Wireless Sensor Networks
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作者 Perumal Kalyanasundaram Thangavel Gnanasekaran 《Circuits and Systems》 2016年第10期3343-3353,共12页
In Wireless Sensor Networks (WSN), the lifetime of sensors is the crucial issue. Numerous schemes are proposed to augment the life time of sensors based on the wide range of parameters. In majority of the cases, the c... In Wireless Sensor Networks (WSN), the lifetime of sensors is the crucial issue. Numerous schemes are proposed to augment the life time of sensors based on the wide range of parameters. In majority of the cases, the center of attraction will be the nodes’ lifetime enhancement and routing. In the scenario of cluster based WSN, multi-hop mode of communication reduces the communication cast by increasing average delay and also increases the routing overhead. In this proposed scheme, two ideas are introduced to overcome the delay and routing overhead. To achieve the higher degree in the lifetime of the nodes, the residual energy (remaining energy) of the nodes for multi-hop node choice is taken into consideration first. Then the modification in the routing protocol is evolved (Multi-Hop Dynamic Path-Selection Algorithm—MHDP). A dynamic path updating is initiated in frequent interval based on nodes residual energy to avoid the data loss due to path extrication and also to avoid the early dying of nodes due to elevation of data forwarding. The proposed method improves network’s lifetime significantly. The diminution in the average delay and increment in the lifetime of network are also accomplished. The MHDP offers 50% delay lesser than clustering. The average residual energy is 20% higher than clustering and 10% higher than multi-hop clustering. The proposed method improves network lifetime by 40% than clustering and 30% than multi-hop clustering which is considerably much better than the preceding methods. 展开更多
关键词 Wireless Sensor Networks (WSN) Cluster Based WSN Multi-Hop Mode Residual Energy Average Delay Multi-Hop Dynamic Path-Selection Algorithm life time
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Sensitivity of the half-life time of water exchange in coastal waters 被引量:1
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作者 Zhenhua CHEN Fangli QIAO +1 位作者 Gang WANG Changshui XIA 《Science China Earth Sciences》 SCIE EI CAS CSCD 2019年第4期643-656,共14页
A three-dimensional model was established to investigate water exchange in coastal waters, and applied to Qinzhou Bay(QZB) in the South China Sea. Given the strong tidal current in QZB, a half-life time was calculated... A three-dimensional model was established to investigate water exchange in coastal waters, and applied to Qinzhou Bay(QZB) in the South China Sea. Given the strong tidal current in QZB, a half-life time was calculated for water exchange by filtering the tidal signal from the concentrations of a conservative substance. In a control run driven by the tide, without external inputs and an open boundary concentration of zero, it was estimated that the average half-life time in QZB was 54.8 d. Numerical experiments showed that wind accounted for an 11.9% reduction in the half-life time to 48.3 d. When rivers were included in the model, the half-life time decreased by 74.6% to 13.9 d. Sensitivity experiments showed that the half-life time for water exchange was greatly affected by the concentration of the conservative substance which was used at the open boundary. In response to 10,20, 30, and 40% increases in the boundary concentration, the half-life time increased to 91.5, 168.3, 186.2, and 229.1 d,respectively. Results also suggested that for coastal bays with large intertidal areas such as QZB, consideration of the wet and dry processes produced more accurate simulations of the hydrodynamics and the half-life times. Simulations, which did not incorporate wet and dry processes, were more than likely to have overestimated or underestimated the half-life times for water exchange. 展开更多
关键词 Sensitivity CONVECTION-DIFFUSION model Water exchange HALF-life time Qinzhou BAY SOUTH China SEA
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A Novel Multiple Dependent State Sampling Plan Based on Time Truncated Life Tests Using Mean Lifetime 被引量:1
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作者 Pramote Charongrattanasakul Wimonmas Bamrungsetthapong Poom Kumam 《Computers, Materials & Continua》 SCIE EI 2022年第12期4611-4626,共16页
The design of a new adaptive version of the multiple dependent state(AMDS)sampling plan is presented based on the time truncated life test under the Weibull distribution.We achieved the proposed sampling plan by apply... The design of a new adaptive version of the multiple dependent state(AMDS)sampling plan is presented based on the time truncated life test under the Weibull distribution.We achieved the proposed sampling plan by applying the concept of the double sampling plan and existing multiple dependent state sampling plans.A warning sign for acceptance number was proposed to increase the probability of current lot acceptance.The optimal plan parameters were determined simultaneously with nonlinear optimization problems under the producer’s risk and consumer’s risk.A simulation study was presented to support the proposed sampling plan.A comparison between the proposed and existing sampling plans,namely multiple dependent state(MDS)sampling plans and a modified multiple dependent state(MMDS)sampling plan,was considered under the average sampling number and operating characteristic curve values.In addition,the use of two real datasets demonstrated the practicality and usefulness of the proposed sampling plan.The results indicated that the proposed plan is more flexible and efficient in terms of the average sample number compared to the existing MDS and MMDS sampling plans. 展开更多
关键词 Adaptive version of multiple dependent state sampling plan time truncated life test quality level weibull distribution mean lifetime
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Physical activity, screen time and pediatric health-related quality of life in the Mississippi Delta 被引量:3
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作者 Tamara T. Perry Page C. Moore +2 位作者 Karen M. Redwine James M. Robbins Judith L. Weber 《Open Journal of Preventive Medicine》 2012年第1期105-111,共7页
Background: The association of physical activity (PA) and screen time (ST) on health-related quality of life (HRQOL) among predominantly low-income children in the Mississippi Delta region has not been previously desc... Background: The association of physical activity (PA) and screen time (ST) on health-related quality of life (HRQOL) among predominantly low-income children in the Mississippi Delta region has not been previously described. Methods: We performed a cross-sectional survey to assess health risks from a representative sample of the population ≥3 years old in the Delta Region of Arkansas, Louisiana, and Mississippi. Linear models were utilized to examine Pediatric Quality of Life Inventory (PedsQL) scores based on reported PA and ST. Results: Median age of the 371 participants was 9.8 years, 57% were African American, and 26% had annual household income ≤$14,999. Overall, 262 (75%) were categorized as physically active and 48% reported >2 hours ST per day. Children reporting exercising 5 - 7 days per week had significantly better PedsQL total score (84.3 vs 80.8;p 2 hours per day) did not significantly impact HRQOL. Conclusions: Findings suggest that PA among children living in the Mississippi Delta was related to higher HRQOL;however, the positive effects of PA on HRQOL may be less for minority and low-income children. 展开更多
关键词 PHYSICAL ACTIVITY SCREEN time Quality of life PEDIATRICS
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Extending the Network Lifetime Using Optimized Energy Efficient Cross Layer Module (OEEXLM) in Wireless Sensor Networks
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作者 T. V. PADMAVATHY 《Wireless Sensor Network》 2009年第1期27-35,共9页
In wireless sensor network, the primary design is to save the energy consumption as much as possible while achieving the given task. Most of recent researches works have only focused on the individual layer issues and... In wireless sensor network, the primary design is to save the energy consumption as much as possible while achieving the given task. Most of recent researches works have only focused on the individual layer issues and ignore the importance of inter working between different layers in a sensor network. In this paper, we use a cross-layer approach to propose an energy-efficient and extending the life time of the sensor network. This protocol which uses routing in the network layer, and the data scheduling in MAC layer. The main ob-jective of this paper is to provide a possible and flexible approach to solve the conflicts between the require-ments of large scale, long life-time, and multi-purpose wireless sensor networks. This OEEXLM module gives better performance compared to all other existing protocols. The performance of OEEXLM module compared with S-MAC and directed diffusion protocol. 展开更多
关键词 ROUTING MEDIUM ACCESS Control life time of the Network Energy Efficiency OEEXLM MODULE Wireless Sensor Networks
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A Time Dependent Inventory Model for Exponential Demand Rate with Constant Production Where Shelf-Life of the Product Is Finite
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作者 Mohammad Ekramol Islam Shirajul Islam Ukil Md. Sharif Uddin 《Open Journal of Applied Sciences》 2016年第1期38-48,共11页
In this paper a time dependent inventory model is developed on the basis of constant production rate and market demands which are exponentially decreasing. It advances in quest of total average optimum cost considerin... In this paper a time dependent inventory model is developed on the basis of constant production rate and market demands which are exponentially decreasing. It advances in quest of total average optimum cost considering those products which have finite shelf-life. The model also considers the small amount of decay. Without having any sort of backlogs, production starts. Reaching at the desired level of inventories, it stops production. After that due to demands along with the deterioration of the items it initiates its depletion and after certain periods the inventory gets zero. The decay of the products is level dependent. The objective of this paper is to find out the optimum inventory cost and optimum time cycle. The model has also been justified with proving the convex property and by giving a numerical example. 展开更多
关键词 Production Inventory Shelf-life time Dependent Demand Class Production Rate
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Remaining useful life estimation for deteriorating systems with time-varying operational conditions and condition-specific failure zones 被引量:6
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作者 Li Qi Gao Zhanbao +1 位作者 Tang Diyin Li Baoan 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2016年第3期662-674,共13页
Dynamic time-varying operational conditions pose great challenge to the estimation of system remaining useful life (RUL) for the deteriorating systems. This paper presents a method based on probabilistic and stochas... Dynamic time-varying operational conditions pose great challenge to the estimation of system remaining useful life (RUL) for the deteriorating systems. This paper presents a method based on probabilistic and stochastic approaches to estimate system RUL for periodically moni- tored degradation processes with dynamic time-varying operational conditions and condition- specific failure zones. The method assumes that the degradation rate is influenced by specific oper- ational condition and moreover, the transition between different operational conditions plays the most important role in affecting the degradation process. These operational conditioqs are assumed to evolve as a discrete-time Markov chain (DTMC). The failure thresholds are also determined by specific operational conditions and described as different failure zones. The 2008 PHM Conference Challenge Data is utilized to illustrate our method, which contains mass sensory signals related to the degradation process of a commercial turbofan engine. The RUE estimation method using the sensor measurements of a single sensor was first developed, and then multiple vital sensors were selected through a particular optimization procedure in order to increase the prediction accuracy. The effectiveness and advantages of the proposed method are presented in a comparison with exist- ing methods for the same dataset. 展开更多
关键词 Degradation Discrete-time Markov chainOperational conditions Remaining useful life esti-mation Sensor selection
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基于时间相关性的超期服役球罐的检验研究
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作者 吕文涛 陈道琰 +1 位作者 吴晓风 王墅 《化工设备与管道》 北大核心 2025年第2期9-14,共6页
文章介绍了超设计使用年限压力容器的检验方法现状,给出了缺陷时间相关性的含义,通过引入时间相关性的检验理念,对一台超设计使用年限的、储存氯乙烯介质的球形储罐进行了检验研究。通过查阅分析该设备的组焊、维保、定期自行检查、定... 文章介绍了超设计使用年限压力容器的检验方法现状,给出了缺陷时间相关性的含义,通过引入时间相关性的检验理念,对一台超设计使用年限的、储存氯乙烯介质的球形储罐进行了检验研究。通过查阅分析该设备的组焊、维保、定期自行检查、定期检验等资料,分析了设备可能存在的损伤模式,制定了专用检验方案,包括宏观检验,壁厚测定,互补性无损检测、硬度检测、腐蚀产物分析等项目。检出的主要缺陷包括裂纹、夹渣、圆形气孔,条形气孔等缺陷。经对缺陷逐一进行时间相关性分析,最终发现,裂纹缺陷具有良性的非线性时间相关性特点,而其他缺陷不具备时间相关性,经适当修理,该设备可继续安全使用至下一检验周期,文章引入的缺陷—时间相关性分析方法可为超设计使用年限压力容器的检验提供一种新的思路和理念。 展开更多
关键词 设计使用年限 缺陷 时间相关性 检验
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前瞻性护理在预防机械通气患者ICU获得性衰弱中的应用 被引量:1
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作者 张金萍 陶钰 《空军航空医学》 2025年第1期84-87,共4页
目的 探究前瞻性护理在预防机械通气患者发生ICU获得性衰弱(intensive care unit-acquired weakness,ICU-AW)中的作用。方法 选取2022年8月—2023年12月于南京医科大学附属南京医院呼吸与危重症医学科收治的67例机械通气患者。按照随机... 目的 探究前瞻性护理在预防机械通气患者发生ICU获得性衰弱(intensive care unit-acquired weakness,ICU-AW)中的作用。方法 选取2022年8月—2023年12月于南京医科大学附属南京医院呼吸与危重症医学科收治的67例机械通气患者。按照随机数字表法分为对照组(n=33)和研究组(n=34),对照组接受常规护理,研究组在常规护理的基础上接受前瞻性护理。采用医学研究委员会肌力评分(Medical Research Council Muscle Strength,MRC)比较2组肌力,采用日常生活活动量表(Activity of Daily Living,ADL)及巴氏指数(Barthel Index,BI)量表评估2组日常生活能力。采用焦虑自评量表(Self-Rating Anxiety Scale,SAS)及抑郁自评量表(Self-Rating Depression Scale,SDS)评估患者的焦虑、抑郁状态,统计2组患者的机械通气时间及住院时间。结果 护理前2组患者的MRC评分差异无统计学意义(P>0.05),研究组患者护理前后的MRC得分差值高于对照组,差异具有统计学意义(t=4.082,P<0.001);护理前2组患者的ADL得分差异无统计学意义(P>0.05),研究组患者护理前后ADL评分差值高于对照组,差异具有统计学意义(t=8.906,P<0.001);护理前2组患者的BI评分无统计学意义(P>0.05),研究组患者护理前后BI评分差值高于对照组,差异具有统计学意义(t=2.386,P=0.036);护理前2组患者SAS评分及SDS评分差异均无统计学意义(P>0.05),研究组患者护理前后SAS评分及SDS评分差值均高于对照组,差异具有统计学意义(t=5.064、5.238,P均<0.001);研究组患者机械通气时间低于对照组(t=11.063,P<0.001),研究组患者平均住院时间低于对照组(t=10.169,P<0.001)。结论 前瞻性护理可以有效预防ICU-AW,提高患者自理能力,同时缓解患者焦虑、抑郁心理状态,减少其机械通气时间及住院时间,值得在临床中进一步研究与推广。 展开更多
关键词 ICU获得性衰弱 前瞻性护理 生活质量 机械通气时间
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数字生命之境:自在、自觉与自律
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作者 余乃忠 宫曼露 《哲学分析》 北大核心 2025年第3期153-168,199,共17页
在图灵和冯·诺伊曼的研究基础上,数字生命已通过模型被证实存在,并以一种超越时空限度、单一主体和碳基实体的状态发展。在实与虚的复合变量下,数字生命通过语言、物像与自组织性所体现出的时空自由度、意识承载度和意义叠加度也... 在图灵和冯·诺伊曼的研究基础上,数字生命已通过模型被证实存在,并以一种超越时空限度、单一主体和碳基实体的状态发展。在实与虚的复合变量下,数字生命通过语言、物像与自组织性所体现出的时空自由度、意识承载度和意义叠加度也使其在本体意义上重新建构了关于生命的存在形式、认知界域及意义世界。从数字生命的跨时空自我存在阐释其基于硅基中介的数字基元,从自我迭代到与物化生命交互解构其意识的自觉性,从自然生命的系统性衰减揭示数字生命的抗耗散结构的自律意义,都在展示“数字自己构成自己”的独特进化道路。 展开更多
关键词 数字生命 存在 时空 意识 负熵 意义
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灵活工作时间、弹性退休年龄与一生收入
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作者 王云多 《经济与管理》 北大核心 2025年第6期56-63,共8页
随着人口老龄化加剧,为实现个人一生收入最大化,考虑个人在劳动收入和投资收益不确定情况下作出工作时间和退休年龄选择,进而推导个人最优生命周期资产配置模式。研究结果表明,劳动收入和投资收益不确定以复杂的方式影响退休和资产配置... 随着人口老龄化加剧,为实现个人一生收入最大化,考虑个人在劳动收入和投资收益不确定情况下作出工作时间和退休年龄选择,进而推导个人最优生命周期资产配置模式。研究结果表明,劳动收入和投资收益不确定以复杂的方式影响退休和资产配置模式,劳动力市场的负向冲击和高额的股票收益促使年轻人减少工作时间,转而增加年金购买,之后作出提前退休决定,这种灵活性有利于增强个人福利。此外,研究结果还表明,个人生命周期中劳动收入呈V形,如果允许个人灵活选择退休年龄,存在退休时消费明显不连续和老年家庭对年金认购率低等问题。 展开更多
关键词 生命周期 工作时间 退休年龄 投资组合
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基于多阶段退化建模的3D舞台威亚控制系统实时寿命预测
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作者 毛海杰 李伟林 李炜 《兰州理工大学学报》 北大核心 2025年第5期72-80,共9页
针对3D舞台威亚系统因执行电机退化导致系统寿命不足而产生安全隐患的问题,提出基于多阶段退化模型的系统实时剩余寿命预测方法.首先采用多阶段Wiener过程对伺服电机绝缘老化进行建模,并利用累积和(CUSUM)检验进行变点检测,实现阶段划分... 针对3D舞台威亚系统因执行电机退化导致系统寿命不足而产生安全隐患的问题,提出基于多阶段退化模型的系统实时剩余寿命预测方法.首先采用多阶段Wiener过程对伺服电机绝缘老化进行建模,并利用累积和(CUSUM)检验进行变点检测,实现阶段划分;其次考虑测量噪声的影响,借助Kalman滤波以及RTS平滑算法估计真实退化状态,并将变点检测结果融入基于期望最大化(EM)算法的参数估计过程,实现模型参数的实时在线更新与阶段更替;最后,以实时位置误差为系统性能评价指标,实现了对3D舞台威亚的系统级在线剩余寿命(RUL)预测.仿真结果表明,该方法不仅可准确识别退化过程各阶段变化时刻,且更为契合实际退化过程,能够有效提高剩余寿命预测精度,从而为后续的精准维护提供可靠依据. 展开更多
关键词 3D舞台威亚系统 多阶段退化建模 变点检测 系统级实时寿命预测
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基于KF-TCN方法的航空发动机寿命预测
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作者 刘纯志 《科学技术与工程》 北大核心 2025年第27期11607-11613,共7页
为解决传统预测方法在涡扇发动机剩余使用寿命(remaining useful life,RUL)预测精度较低的问题,提出了一种基于卡尔曼滤波与时间卷积神经网络(temporal convolutional network,TCN)相结合的涡扇发动机寿命预测方法。首先,为减小传感器... 为解决传统预测方法在涡扇发动机剩余使用寿命(remaining useful life,RUL)预测精度较低的问题,提出了一种基于卡尔曼滤波与时间卷积神经网络(temporal convolutional network,TCN)相结合的涡扇发动机寿命预测方法。首先,为减小传感器在采集数据时的噪声干扰,使用卡尔曼滤波(Kalman filtering,KF)算法对提取特征进行滤波处理。其次,构建KF-TCN模型,将滤波后数据输入到时间卷积网络中,捕捉时序数据中的时间依赖性并输出RUL预测值。最后,以FD001子集为例,使用商用模块化航空推进系统仿真(commercial modular aero-propulsion system simulation,C-MAPSS)航空发动机数据集对模型进行仿真试验验证。研究结果表明:与TCN、门控循环单元神经网络(gated recurrent unit,GRU)和长短期记忆人工神经网络(long short-term memory,LSTM)模型RUL预测结果相比较,本文所构建KF-TCN模型在发动机RUL预测过程中预测误差较小,为发动机寿命预测提供新思路。 展开更多
关键词 航空发动机 剩余使用寿命预测 卡尔曼滤波 时间卷积神经网络
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航空管路无扩口管接头寿命预测方法研究 被引量:1
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作者 唐杰 孙茹 《重庆理工大学学报(自然科学)》 北大核心 2025年第2期154-162,共9页
为提升对航空管路无扩口接头退化预测的精度和效率,提出一种基于时间卷积网络TCN(temporal convolutional network)和Transformer的特征融合模型(TT模型)。通过TCN模块提取增强后的特征信息,利用融合卷积Transformer模块进一步处理,在... 为提升对航空管路无扩口接头退化预测的精度和效率,提出一种基于时间卷积网络TCN(temporal convolutional network)和Transformer的特征融合模型(TT模型)。通过TCN模块提取增强后的特征信息,利用融合卷积Transformer模块进一步处理,在编码器末尾添加池化层以降低过拟合风险,最终通过全连接层得到预测结果。为验证TT模型的有效性,针对航空管路无扩口接头密封性能使用单向流固耦合方法完成泄漏率模型的建立并获取数据,利用数据集进行试验。结果表明,TT模型与CNN、RNN、LSTM和Transformer模型相比,预测误差分别减少3.53%、6.08%、1.63%和1.75%,有效提高了航空管路无扩口接头退化预测的准确性。 展开更多
关键词 时间序列预测 密封特性 TCN TRANSFORMER 寿命预测
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考虑退化相关性的电解电容实时剩余寿命预测
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作者 李小波 汪翔 王睿轶 《燕山大学学报》 北大核心 2025年第2期146-154,共9页
目前对于电解电容的退化特性研究多是基于单个退化特征,难以精确预测电容的剩余寿命。针对这一现状,本文提出考虑退化特征相关性的二元线性Wiener过程退化模型进行电容剩余寿命实时预测。首先利用Box-Cox变换对电容退化数据进行线性化处... 目前对于电解电容的退化特性研究多是基于单个退化特征,难以精确预测电容的剩余寿命。针对这一现状,本文提出考虑退化特征相关性的二元线性Wiener过程退化模型进行电容剩余寿命实时预测。首先利用Box-Cox变换对电容退化数据进行线性化处理,然后将极大似然估计结合自助抽样法得到的模型参数经Bayesian理论进行实时更新,并利用蒙特卡洛算法求解电容的剩余寿命分布,最后通过NASA试验数据进行了验证,并与基于Copula函数处理相关性的算法进行了对比。结果表明,本文算法的预测精度较只考虑电容容值、只考虑等效串联电阻的一维Wiener过程模型分别提高约0.7298%,0.0913%,比基于Copula理论的算法预测精度提高了约0.0832%,可为制订电解电容的视情维修策略提供依据。 展开更多
关键词 电解电容 实时剩余寿命预测 二元维纳过程 Box-Cox变换 Bayesian理论
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