An opportunistic maintenance model is presented for a continuously deteriorating series system with economical de-pendence. The system consists of two kinds of units, which are respectively subjected to the deteriorat...An opportunistic maintenance model is presented for a continuously deteriorating series system with economical de-pendence. The system consists of two kinds of units, which are respectively subjected to the deterioration failure described by Gamma process and the random failure described by Poisson process. A two-level opportunistic policy defined by three decision parameters is proposed to coordinate the different maintenance actions and minimize the long-run maintenance cost rate of the system. A computable expression of the average cost rate is established by using the renewal property of the stochastic process of the maintained system state. The optimal values of three deci- sion parameters are derived by an iteration approach based on the characteristic of Gamma process. The behavior of the proposed policy is illustrated through a numerical experiment. Comparative study with the widely used corrective maintenance policy demonstrates the advantage of the proposed opportunistic maintenance method in significantly reducing the maintenance cost. Simultane- ously, the applicable area of this opportunistic model is discussed by the sensitivity analysis of the set-up cost and random failure rate.展开更多
Background:Our goal is to build a multi-unit ocular biometric system based on the fusion of left and right corneal shapes for identity authentication.Methods:Ocular biometrics such as iris,periocular,retina,sclera and...Background:Our goal is to build a multi-unit ocular biometric system based on the fusion of left and right corneal shapes for identity authentication.Methods:Ocular biometrics such as iris,periocular,retina,sclera and eye movement have become established biometric traits,primarily due to extensive efforts made by the biometrics community in the field of iris recognition.In this work,we propose an ocular biometric trait based on the 3D shape of the cornea to improve biometric authentication.We show how the fusion of the left and right corneas can be used as a biometric trait for person recognition.First,we started by realizing our own cornea database by using a Pentacam Topographer(Oculus)which contains 288 corneal topographies of both eyes captured from 36 different people of different ages.For each eye,data acquisition was done during two different sessionsto establish the repeatability of the measurements over time.The time interval between the two sessions was equal or greater than one month.In each session;8 acquisitions(4 left eyes end 4 right eyes)were taken.Then,features were extracted by modeling the shape of the left and right corneas with a Zernike polynomial expansion.The fusion of the left and right shapes of cornea was performed at the matching score level using the weighted-sum rule.Results:For each individual,we had eight feature vectors(eight measures in two sessions)of size 36(Zernike polynomial coefficients)from their corneal topographies.The experimental results on our cornea database constructed for this study showed encouraging performance of the proposed ocular biometric system with Equal Error Rate decreasing to 1.38%with the weighted-sum rule compared to the analysis of the left(4.5%)or right(3.7%)cornea alone.Conclusions:The objective of this work was to investigate corneal topographyas an accurate biometric modality using shape discriminating features.Our idea was to propose an ocular multi-unit system based on the fusion of the left and right corneal shapes.The corneal feature extraction was done by Zernike polynomial decomposition.Multi-unit cornea fusion was performed at the matching score level to generate a unique score.This allowed a significative decrease of the EER to 1.38%.展开更多
The pharmaceutical industry faces challenges in quality digitization for complex multi-stage processes,especially in small-sample systems.Here,an intelligent quality prediction and diagnostic(IQPD)framework was develo...The pharmaceutical industry faces challenges in quality digitization for complex multi-stage processes,especially in small-sample systems.Here,an intelligent quality prediction and diagnostic(IQPD)framework was developed and applied to Tong Ren Tang’s Niuhuang Qingxin Pills,utilizing four years of data collected from four production units,covering the entire process from raw materials to finished products.In this framework,a novel path-enhanced double ensemble quality prediction model(PeDGAT)is proposed,which combines a graph attention network and path information to encode inter-unit long-range and sequential dependencies.Additionally,the double ensemble strategy enhances model stability in small samples.Compared to global traditional models,PeDGAT achieves state-of-the-art results,with an average improvement of 13.18% and 87.67% in prediction accuracy and stability on three indicators.Additionally,a more in-depth diagnostic model leveraging grey correlation analysis and expert knowledge reduces reliance on large samples,offering a panoramic view of attribute relationships across units and improving process transparency.Finally,the IQPD framework integrates into a Human-Cyber-Physical system,enabling faster decision-making and real-time quality adjustments for Tong Ren Tang’s Niuhuang Qingxin Pills,a product with annual sales exceeding 100 million CNY.This facilitates the transition from experience-driven to data-driven manufacturing.展开更多
Auction was widely used to tackle spectrum allocation and sharing in the secondary market under the condition of spectrum scarcity. In real communication system, such as broadband communication, the utilization of spe...Auction was widely used to tackle spectrum allocation and sharing in the secondary market under the condition of spectrum scarcity. In real communication system, such as broadband communication, the utilization of spectrum resource is various because of different requirements and complex application scenarios. So, these schemes cannot be directly applied to the above wireless communication system. To solve this problem, a new model where sellers/buyers can sell/buy multi-unit for heterogeneous spectrum was proposed and a truthful multi-unit double auction framework was designed for heterogeneous spectrum trading. A valuation function is first applied to represent the buyer's true valuation of the sub-band and reflect the buyer's satisfaction degree and a novel concept termed ‘virtual player' was introduced. Then the buyer group was constructed based on the conflict graph to reuse the same spectrum among interference-free buyers in both spatial and temporal domains. The winner determination strategy and algorithm of clearing price were designed elaborately. According to the theoretical analysis, the scheme can satisfy three critical economic properties: truthfulness, individual rationality, and budget balance. Finally, simulation results show that the proposed scheme can achieve better user satisfaction, auction efficiency and spectrum reuse rate for the real communication system. The proposed auction framework is practical and effective.展开更多
A homogenous multi-unit auction model is studied in two conditions： One is that the bidders face budget constraints and another is that the bidders do not face budget constraints. Two equilibrium bidding strategies o...A homogenous multi-unit auction model is studied in two conditions： One is that the bidders face budget constraints and another is that the bidders do not face budget constraints. Two equilibrium bidding strategies of each bidder are presented in these two conditions. By comparing them, the authors show that the equilibrium unit price bid in the presence of budget constraints will be less than that in the absence of budget constraints. The difference between the two equilibrium bids leads to the reduced revenue of the seller. And this difference will decrease as the number of the bidders increases.展开更多
方面级情感分析旨在识别文本中针对特定方面的情感倾向,然而现有研究仍面临多重挑战:基于BERT的方面级情感分析研究存在语义过拟合、低层级语义利用不足的问题;自注意力机制存在局部信息丢失的问题;多编码层和多粒度语义的结构存在信息...方面级情感分析旨在识别文本中针对特定方面的情感倾向,然而现有研究仍面临多重挑战:基于BERT的方面级情感分析研究存在语义过拟合、低层级语义利用不足的问题;自注意力机制存在局部信息丢失的问题;多编码层和多粒度语义的结构存在信息冗余问题。为此,提出一种融合BERT编码层的多粒度语义方面级情感分析模型(multi-granular semantic aspect-based sentiment analysis model with fusion of BERT encoding layers,MSBEL)。具体地,引入金字塔注意力机制,利用各个编码层的语义特征,并结合低层编码器以降低过拟合;通过多尺度门控卷积增强模型处理局部信息丢失的能力;使用余弦注意力突出与方面词相关的情感特征,从而减少信息冗余。t-SNE的可视化分析表明,MSBEL的情感表示聚类效果优于BERT。此外,在多个基准数据集上将本文模型与主流模型的性能进行了对比,结果显示:与LCF-BERT相比,本文模型在5个数据集上的F1分别提升了1.53%、3.94%、1.39%、6.68%、5.97%;与SenticGCN相比,本文模型的F1平均提升0.94%,最大提升2.12%;与ABSA-DeBERTa相比,本文模型的F1平均提升1.16%,最大提升4.20%,验证了本文模型在方面级情感分析任务上的有效性和优越性。展开更多
基金supported by the National Natural Science Foundation of China(6090400271201166)
文摘An opportunistic maintenance model is presented for a continuously deteriorating series system with economical de-pendence. The system consists of two kinds of units, which are respectively subjected to the deterioration failure described by Gamma process and the random failure described by Poisson process. A two-level opportunistic policy defined by three decision parameters is proposed to coordinate the different maintenance actions and minimize the long-run maintenance cost rate of the system. A computable expression of the average cost rate is established by using the renewal property of the stochastic process of the maintained system state. The optimal values of three deci- sion parameters are derived by an iteration approach based on the characteristic of Gamma process. The behavior of the proposed policy is illustrated through a numerical experiment. Comparative study with the widely used corrective maintenance policy demonstrates the advantage of the proposed opportunistic maintenance method in significantly reducing the maintenance cost. Simultane- ously, the applicable area of this opportunistic model is discussed by the sensitivity analysis of the set-up cost and random failure rate.
文摘Background:Our goal is to build a multi-unit ocular biometric system based on the fusion of left and right corneal shapes for identity authentication.Methods:Ocular biometrics such as iris,periocular,retina,sclera and eye movement have become established biometric traits,primarily due to extensive efforts made by the biometrics community in the field of iris recognition.In this work,we propose an ocular biometric trait based on the 3D shape of the cornea to improve biometric authentication.We show how the fusion of the left and right corneas can be used as a biometric trait for person recognition.First,we started by realizing our own cornea database by using a Pentacam Topographer(Oculus)which contains 288 corneal topographies of both eyes captured from 36 different people of different ages.For each eye,data acquisition was done during two different sessionsto establish the repeatability of the measurements over time.The time interval between the two sessions was equal or greater than one month.In each session;8 acquisitions(4 left eyes end 4 right eyes)were taken.Then,features were extracted by modeling the shape of the left and right corneas with a Zernike polynomial expansion.The fusion of the left and right shapes of cornea was performed at the matching score level using the weighted-sum rule.Results:For each individual,we had eight feature vectors(eight measures in two sessions)of size 36(Zernike polynomial coefficients)from their corneal topographies.The experimental results on our cornea database constructed for this study showed encouraging performance of the proposed ocular biometric system with Equal Error Rate decreasing to 1.38%with the weighted-sum rule compared to the analysis of the left(4.5%)or right(3.7%)cornea alone.Conclusions:The objective of this work was to investigate corneal topographyas an accurate biometric modality using shape discriminating features.Our idea was to propose an ocular multi-unit system based on the fusion of the left and right corneal shapes.The corneal feature extraction was done by Zernike polynomial decomposition.Multi-unit cornea fusion was performed at the matching score level to generate a unique score.This allowed a significative decrease of the EER to 1.38%.
基金graciously supported by the National Key R&D Program of China(2023YFC3504505)National Medical Research and Development Platform for Industry Education Integration Innovation of China―Traditional Chinese Medicine Smart Manufacturing Engineering(90010062820031,China)Undergraduate and Postgraduate Research Project of Beijing University of Chinese Medicine(BXX23018,China).
文摘The pharmaceutical industry faces challenges in quality digitization for complex multi-stage processes,especially in small-sample systems.Here,an intelligent quality prediction and diagnostic(IQPD)framework was developed and applied to Tong Ren Tang’s Niuhuang Qingxin Pills,utilizing four years of data collected from four production units,covering the entire process from raw materials to finished products.In this framework,a novel path-enhanced double ensemble quality prediction model(PeDGAT)is proposed,which combines a graph attention network and path information to encode inter-unit long-range and sequential dependencies.Additionally,the double ensemble strategy enhances model stability in small samples.Compared to global traditional models,PeDGAT achieves state-of-the-art results,with an average improvement of 13.18% and 87.67% in prediction accuracy and stability on three indicators.Additionally,a more in-depth diagnostic model leveraging grey correlation analysis and expert knowledge reduces reliance on large samples,offering a panoramic view of attribute relationships across units and improving process transparency.Finally,the IQPD framework integrates into a Human-Cyber-Physical system,enabling faster decision-making and real-time quality adjustments for Tong Ren Tang’s Niuhuang Qingxin Pills,a product with annual sales exceeding 100 million CNY.This facilitates the transition from experience-driven to data-driven manufacturing.
基金supported by the National Natural Science Foundation of China(61531007,51877010)
文摘Auction was widely used to tackle spectrum allocation and sharing in the secondary market under the condition of spectrum scarcity. In real communication system, such as broadband communication, the utilization of spectrum resource is various because of different requirements and complex application scenarios. So, these schemes cannot be directly applied to the above wireless communication system. To solve this problem, a new model where sellers/buyers can sell/buy multi-unit for heterogeneous spectrum was proposed and a truthful multi-unit double auction framework was designed for heterogeneous spectrum trading. A valuation function is first applied to represent the buyer's true valuation of the sub-band and reflect the buyer's satisfaction degree and a novel concept termed ‘virtual player' was introduced. Then the buyer group was constructed based on the conflict graph to reuse the same spectrum among interference-free buyers in both spatial and temporal domains. The winner determination strategy and algorithm of clearing price were designed elaborately. According to the theoretical analysis, the scheme can satisfy three critical economic properties: truthfulness, individual rationality, and budget balance. Finally, simulation results show that the proposed scheme can achieve better user satisfaction, auction efficiency and spectrum reuse rate for the real communication system. The proposed auction framework is practical and effective.
基金supported by the National Natural Science Foundation of China under Grant No.70771041the Scientific Research Foundation for the Returned Overseas Chinese Scholars from State Education Ministry
文摘A homogenous multi-unit auction model is studied in two conditions： One is that the bidders face budget constraints and another is that the bidders do not face budget constraints. Two equilibrium bidding strategies of each bidder are presented in these two conditions. By comparing them, the authors show that the equilibrium unit price bid in the presence of budget constraints will be less than that in the absence of budget constraints. The difference between the two equilibrium bids leads to the reduced revenue of the seller. And this difference will decrease as the number of the bidders increases.
文摘方面级情感分析旨在识别文本中针对特定方面的情感倾向,然而现有研究仍面临多重挑战:基于BERT的方面级情感分析研究存在语义过拟合、低层级语义利用不足的问题;自注意力机制存在局部信息丢失的问题;多编码层和多粒度语义的结构存在信息冗余问题。为此,提出一种融合BERT编码层的多粒度语义方面级情感分析模型(multi-granular semantic aspect-based sentiment analysis model with fusion of BERT encoding layers,MSBEL)。具体地,引入金字塔注意力机制,利用各个编码层的语义特征,并结合低层编码器以降低过拟合;通过多尺度门控卷积增强模型处理局部信息丢失的能力;使用余弦注意力突出与方面词相关的情感特征,从而减少信息冗余。t-SNE的可视化分析表明,MSBEL的情感表示聚类效果优于BERT。此外,在多个基准数据集上将本文模型与主流模型的性能进行了对比,结果显示:与LCF-BERT相比,本文模型在5个数据集上的F1分别提升了1.53%、3.94%、1.39%、6.68%、5.97%;与SenticGCN相比,本文模型的F1平均提升0.94%,最大提升2.12%;与ABSA-DeBERTa相比,本文模型的F1平均提升1.16%,最大提升4.20%,验证了本文模型在方面级情感分析任务上的有效性和优越性。
