The corrosion rate is a crucial factor that impacts the longevity of materials in different applications.After undergoing friction stir processing(FSP),the refined grain structure leads to a notable decrease in corros...The corrosion rate is a crucial factor that impacts the longevity of materials in different applications.After undergoing friction stir processing(FSP),the refined grain structure leads to a notable decrease in corrosion rate.However,a better understanding of the correlation between the FSP process parameters and the corrosion rate is still lacking.The current study used machine learning to establish the relationship between the corrosion rate and FSP process parameters(rotational speed,traverse speed,and shoulder diameter)for WE43 alloy.The Taguchi L27 design of experiments was used for the experimental analysis.In addition,synthetic data was generated using particle swarm optimization for virtual sample generation(VSG).The application of VSG has led to an increase in the prediction accuracy of machine learning models.A sensitivity analysis was performed using Shapley Additive Explanations to determine the key factors affecting the corrosion rate.The shoulder diameter had a significant impact in comparison to the traverse speed.A graphical user interface(GUI)has been created to predict the corrosion rate using the identified factors.This study focuses on the WE43 alloy,but its findings can also be used to predict the corrosion rate of other magnesium alloys.展开更多
A reliability-based stochastic system optimum congestion pricing(SSOCP) model with endogenous market penetration and compliance rate in an advanced traveler information systems(ATIS) environment was proposed. All trav...A reliability-based stochastic system optimum congestion pricing(SSOCP) model with endogenous market penetration and compliance rate in an advanced traveler information systems(ATIS) environment was proposed. All travelers were divided into two classes. The first guided travelers were referred to as the equipped travelers who follow ATIS advice, while the second unguided travelers were referred to as the unequipped travelers and the equipped travelers who do not follow the ATIS advice(also referred to as non-complied travelers). Travelers were assumed to take travel time, congestion pricing, and travel time reliability into account when making travel route choice decisions. In order to arrive at on time, travelers needed to allow for a safety margin to their trip.The market penetration of ATIS was determined by a continuous increasing function of the information benefit, and the ATIS compliance rate of equipped travelers was given as the probability of the actually experienced travel costs of guided travelers less than or equal to those of unguided travelers. The analysis results could enhance our understanding of the effect of travel demand level and travel time reliability confidence level on the ATIS market penetration and compliance rate; and the effect of travel time perception variation of guided and unguided travelers on the mean travel cost savings(MTCS) of the equipped travelers, the ATIS market penetration, compliance rate, and the total network effective travel time(TNETT).展开更多
AIM:To characterize the prevalence of hepatitis C virus(HCV)infection among Chinese intravenous drug users(IDUs).METHODS:A total of 432 adult IDUs(95 women and337 men)in Shanghai were included in the study.The third-g...AIM:To characterize the prevalence of hepatitis C virus(HCV)infection among Chinese intravenous drug users(IDUs).METHODS:A total of 432 adult IDUs(95 women and337 men)in Shanghai were included in the study.The third-generation Elecsys Anti-HCV assay(Roche Diagnostics GmbH,Sandhofer Strasse 116,D-68305,Mannheim,Germany)was used to screen for antibodies against HCV.The RIBA strip,a supplemental antiHCV test with high specificity,was performed on all of the samples that tested positive during the initial screening.All of the anti-HCV positive samples were analyzed with a Cobas TaqMan 48 Analyzer(Roche Diagnostics)for direct detection of HCV RNA.All of the HCV RNA-positive samples were sequenced for genotype determination.RESULTS:The preliminary screening identified 262(60.6%)subjects who were seropositive for HCV.Of the 62 females and 200 males seropositive subjects,16(16.7%)and 65(19.3%),respectively,were confirmed by RIBA,yielding an overall HCV seropositive rate of18.8%.Four female(6.5%)and 14 male(7.0%)subjects tested positive for HCV RNA,indicating an active infection rate of 4.2%for the entire study population.The 18 HCV RNA-positive serum samples were genotyped.Seven individuals were genotype 1b,and four were genotype 1a.One individual each was infected with genotypes 2a,2b and 3a.Four subjects were coinfected with multiple strains:two with genotypes 1a and 2a,and two with genotypes 1b and 2a.The active infection rate among HCV-seropositive individuals was22.2%,which was significantly lower than most estimates.CONCLUSION:The prevalence of HCV is relatively low among IDUs in Shanghai,with a spontaneous recovery rate much higher than previous estimates.展开更多
The interference alignment （IA） algorithm based on FDPM subspace tracking （FDPM-ST IA） is proposed for MIMO cognitive network （CRN） with multiple primary users in this paper. The feasibility conditions of FDPM-S...The interference alignment （IA） algorithm based on FDPM subspace tracking （FDPM-ST IA） is proposed for MIMO cognitive network （CRN） with multiple primary users in this paper. The feasibility conditions of FDPM-ST IA is also got. Futherly, IA scheme of secondary network and IA scheme of primary network are given respectively without assuming a priori knowledge of interference covariance matrices. Moreover, the paper analyses the computational complexity of FDPM-ST IA. Simulation results and theoretical calculations show that the proposed algorithm can achieve higher sum rate with lower computational complexity.展开更多
Multi-user detection (MUD) based on multirate transmission in code division multiple access (CDMA) system is discussed. Under the requirement of signal interference ratio (SIR) detection at base station and framework ...Multi-user detection (MUD) based on multirate transmission in code division multiple access (CDMA) system is discussed. Under the requirement of signal interference ratio (SIR) detection at base station and framework with parallel interference cancellation, a supervision decision algorithm based on pre-decision of probabilistic data association (PDA) and hard decision is proposed. The detection performance is analyzed and simulation is implemented to show that the supervision decision algorithm improves the detection performance effectively.展开更多
目的良好的患者依从率是保证变应原特异性免疫治疗的关键,本研究系统评价变应原皮下特异性免疫治疗(皮下脱敏治疗)患者的依从率及影响因素。方法检索PubMed、Cochrane library、Web of Science、CINAHL,中国生物医学文献数据库(CBM)、...目的良好的患者依从率是保证变应原特异性免疫治疗的关键,本研究系统评价变应原皮下特异性免疫治疗(皮下脱敏治疗)患者的依从率及影响因素。方法检索PubMed、Cochrane library、Web of Science、CINAHL,中国生物医学文献数据库(CBM)、中国知网(CNKI)、万方数据知识服务平台和维普(VIP)数据库,检索时限为建库至2023年8月。采用澳大利亚JBI循证卫生保健中心研究真实性评价标准进行文献评价。采用Revman5.3版软件对皮下脱敏治疗依从率进行Meta分析,对影响依从率的因素采用描述性分析。结果共纳入符合条件的文献28篇,结果显示皮下特异性免疫治疗依从率在23.00%~91.46%之间,合并依从率为67.00%(95%CI:57.00%~77.00%);影响依从率的主要因素包括药物不良反应(1.40%~29.00%)、治疗效果未达预期(2.60%~44.00%)、症状改善(4.00%~60.60%)、经济原因(1.00%~47.90%)等;儿童患者的依从率明显高于成人(OR=0.53,95%CI:0.47~0.61,P<0.000)。结论皮下脱敏治疗的总体依从率偏低,且影响依从率的因素较多,采取个性化措施增加患者依从率是提高皮下脱敏治疗的关键。展开更多
目的探讨品管圈(Quality Control Circle,QCC)管理方法在提高住院患儿雾化吸入依从率的应用价值。方法济宁市第一人民医院儿科雾化吸入QCC管理实施时间自2020年6月开始,选取QCC实施前(2020年4月至2020年5月)0~3岁住院进行雾化吸入治疗...目的探讨品管圈(Quality Control Circle,QCC)管理方法在提高住院患儿雾化吸入依从率的应用价值。方法济宁市第一人民医院儿科雾化吸入QCC管理实施时间自2020年6月开始,选取QCC实施前(2020年4月至2020年5月)0~3岁住院进行雾化吸入治疗的患儿454人以及QCC实施后(2020年11月至12月)0~3岁住院进行雾化吸入治疗的患儿496人进行研究,比较两组住院患儿在雾化吸入治疗中的哭闹发生率、按时雾化率、家属拒绝情况、雾化中断情况,以及总体雾化依从率。结果在QCC实施后,0~3岁住院患儿雾化吸入哭闹发生率下降(23.33%vs 5.04%)、未按时雾化率下降(16.08%vs 2.82%),总体雾化依从率提升(56.00%vs 88.90%),差异有统计学意义(P<0.001);QCC实施后患儿家属满意度评分提升(t=5.95,P<0.001)。结论实施QCC能够提升低于3岁住院患儿雾化吸入依从率,提升患者家属满意度。展开更多
在基于非正交多址接入技术的多用户下行室内可见光通信(Visible light communication system based on non⁃orthogonal multiple access technology,VLC⁃NOMA)系统中,针对和速率与用户公平性冲突的问题,提出一种基于加权和速率最大化的...在基于非正交多址接入技术的多用户下行室内可见光通信(Visible light communication system based on non⁃orthogonal multiple access technology,VLC⁃NOMA)系统中,针对和速率与用户公平性冲突的问题,提出一种基于加权和速率最大化的迭代功率分配方案。该方案以最大化加权和速率为目标,可通过改变权重因子来调节用户公平性。由于目标问题属于非凸优化问题,通过辅助变量法和凸优化理论将该非凸问题转化为凹问题,再通过拉格朗日对偶法进行求解,并根据问题的解设计了一种迭代功率分配算法。对所提算法的收敛性、系统和速率以及用户公平性进行了仿真。结果表明,所提迭代功率分配算法具有良好的收敛性,相较于VLC⁃OMA系统,VLC⁃NOMA系统能够获得更好的和速率性能。通过调整权重因子,在牺牲较小系统和速率的情况下能够获得比现有功率分配方案更好的系统和速率与用户公平性。展开更多
文摘The corrosion rate is a crucial factor that impacts the longevity of materials in different applications.After undergoing friction stir processing(FSP),the refined grain structure leads to a notable decrease in corrosion rate.However,a better understanding of the correlation between the FSP process parameters and the corrosion rate is still lacking.The current study used machine learning to establish the relationship between the corrosion rate and FSP process parameters(rotational speed,traverse speed,and shoulder diameter)for WE43 alloy.The Taguchi L27 design of experiments was used for the experimental analysis.In addition,synthetic data was generated using particle swarm optimization for virtual sample generation(VSG).The application of VSG has led to an increase in the prediction accuracy of machine learning models.A sensitivity analysis was performed using Shapley Additive Explanations to determine the key factors affecting the corrosion rate.The shoulder diameter had a significant impact in comparison to the traverse speed.A graphical user interface(GUI)has been created to predict the corrosion rate using the identified factors.This study focuses on the WE43 alloy,but its findings can also be used to predict the corrosion rate of other magnesium alloys.
基金Project(12YJCZH309) supported by Humanities and Social Sciences Youth Foundation of the Ministry of Education of ChinaProject(20120041120006) supported by Specialized Research Fund for the Doctoral Program of Higher Education,China
文摘A reliability-based stochastic system optimum congestion pricing(SSOCP) model with endogenous market penetration and compliance rate in an advanced traveler information systems(ATIS) environment was proposed. All travelers were divided into two classes. The first guided travelers were referred to as the equipped travelers who follow ATIS advice, while the second unguided travelers were referred to as the unequipped travelers and the equipped travelers who do not follow the ATIS advice(also referred to as non-complied travelers). Travelers were assumed to take travel time, congestion pricing, and travel time reliability into account when making travel route choice decisions. In order to arrive at on time, travelers needed to allow for a safety margin to their trip.The market penetration of ATIS was determined by a continuous increasing function of the information benefit, and the ATIS compliance rate of equipped travelers was given as the probability of the actually experienced travel costs of guided travelers less than or equal to those of unguided travelers. The analysis results could enhance our understanding of the effect of travel demand level and travel time reliability confidence level on the ATIS market penetration and compliance rate; and the effect of travel time perception variation of guided and unguided travelers on the mean travel cost savings(MTCS) of the equipped travelers, the ATIS market penetration, compliance rate, and the total network effective travel time(TNETT).
基金Supported by Science and Technology Commission Xuhui District and Xuhui Health Bureau of ShanghaiNo.SHXH201226
文摘AIM:To characterize the prevalence of hepatitis C virus(HCV)infection among Chinese intravenous drug users(IDUs).METHODS:A total of 432 adult IDUs(95 women and337 men)in Shanghai were included in the study.The third-generation Elecsys Anti-HCV assay(Roche Diagnostics GmbH,Sandhofer Strasse 116,D-68305,Mannheim,Germany)was used to screen for antibodies against HCV.The RIBA strip,a supplemental antiHCV test with high specificity,was performed on all of the samples that tested positive during the initial screening.All of the anti-HCV positive samples were analyzed with a Cobas TaqMan 48 Analyzer(Roche Diagnostics)for direct detection of HCV RNA.All of the HCV RNA-positive samples were sequenced for genotype determination.RESULTS:The preliminary screening identified 262(60.6%)subjects who were seropositive for HCV.Of the 62 females and 200 males seropositive subjects,16(16.7%)and 65(19.3%),respectively,were confirmed by RIBA,yielding an overall HCV seropositive rate of18.8%.Four female(6.5%)and 14 male(7.0%)subjects tested positive for HCV RNA,indicating an active infection rate of 4.2%for the entire study population.The 18 HCV RNA-positive serum samples were genotyped.Seven individuals were genotype 1b,and four were genotype 1a.One individual each was infected with genotypes 2a,2b and 3a.Four subjects were coinfected with multiple strains:two with genotypes 1a and 2a,and two with genotypes 1b and 2a.The active infection rate among HCV-seropositive individuals was22.2%,which was significantly lower than most estimates.CONCLUSION:The prevalence of HCV is relatively low among IDUs in Shanghai,with a spontaneous recovery rate much higher than previous estimates.
基金the National Nature Science Foundation of China under Grant No.61271259 and 61301123,the Chongqing Nature Science Foundation under Grant No.CTSC2011jjA40006,and the Research Project of Chongqing Education Commission under Grant No.KJ120501 and KJ120502
文摘The interference alignment （IA） algorithm based on FDPM subspace tracking （FDPM-ST IA） is proposed for MIMO cognitive network （CRN） with multiple primary users in this paper. The feasibility conditions of FDPM-ST IA is also got. Futherly, IA scheme of secondary network and IA scheme of primary network are given respectively without assuming a priori knowledge of interference covariance matrices. Moreover, the paper analyses the computational complexity of FDPM-ST IA. Simulation results and theoretical calculations show that the proposed algorithm can achieve higher sum rate with lower computational complexity.
文摘Multi-user detection (MUD) based on multirate transmission in code division multiple access (CDMA) system is discussed. Under the requirement of signal interference ratio (SIR) detection at base station and framework with parallel interference cancellation, a supervision decision algorithm based on pre-decision of probabilistic data association (PDA) and hard decision is proposed. The detection performance is analyzed and simulation is implemented to show that the supervision decision algorithm improves the detection performance effectively.
文摘目的良好的患者依从率是保证变应原特异性免疫治疗的关键,本研究系统评价变应原皮下特异性免疫治疗(皮下脱敏治疗)患者的依从率及影响因素。方法检索PubMed、Cochrane library、Web of Science、CINAHL,中国生物医学文献数据库(CBM)、中国知网(CNKI)、万方数据知识服务平台和维普(VIP)数据库,检索时限为建库至2023年8月。采用澳大利亚JBI循证卫生保健中心研究真实性评价标准进行文献评价。采用Revman5.3版软件对皮下脱敏治疗依从率进行Meta分析,对影响依从率的因素采用描述性分析。结果共纳入符合条件的文献28篇,结果显示皮下特异性免疫治疗依从率在23.00%~91.46%之间,合并依从率为67.00%(95%CI:57.00%~77.00%);影响依从率的主要因素包括药物不良反应(1.40%~29.00%)、治疗效果未达预期(2.60%~44.00%)、症状改善(4.00%~60.60%)、经济原因(1.00%~47.90%)等;儿童患者的依从率明显高于成人(OR=0.53,95%CI:0.47~0.61,P<0.000)。结论皮下脱敏治疗的总体依从率偏低,且影响依从率的因素较多,采取个性化措施增加患者依从率是提高皮下脱敏治疗的关键。
文摘在基于非正交多址接入技术的多用户下行室内可见光通信(Visible light communication system based on non⁃orthogonal multiple access technology,VLC⁃NOMA)系统中,针对和速率与用户公平性冲突的问题,提出一种基于加权和速率最大化的迭代功率分配方案。该方案以最大化加权和速率为目标,可通过改变权重因子来调节用户公平性。由于目标问题属于非凸优化问题,通过辅助变量法和凸优化理论将该非凸问题转化为凹问题,再通过拉格朗日对偶法进行求解,并根据问题的解设计了一种迭代功率分配算法。对所提算法的收敛性、系统和速率以及用户公平性进行了仿真。结果表明,所提迭代功率分配算法具有良好的收敛性,相较于VLC⁃OMA系统,VLC⁃NOMA系统能够获得更好的和速率性能。通过调整权重因子,在牺牲较小系统和速率的情况下能够获得比现有功率分配方案更好的系统和速率与用户公平性。
