A pressure swing adsorption (PSA) hydrogen purification model for the four-component gas (H_(2)/CO_(2)/CH_(4)/CO=73/16/8/3 mol%) in a layered bed packed with Cu-BTC and zeolite 5A was established to achieve better hyd...A pressure swing adsorption (PSA) hydrogen purification model for the four-component gas (H_(2)/CO_(2)/CH_(4)/CO=73/16/8/3 mol%) in a layered bed packed with Cu-BTC and zeolite 5A was established to achieve better hydrogen purification performance.By comparing its simulation results with the experimental data,the adsorption isotherm model was validated and could be used to accurately describe the adsorption process of the gas mixture on the two adsorbents.The breakthrough curves of the mixed gas on the layered bed were studied to verify the correctness of the established simulation models.Based on the validated model,the performance of the PSA system based on the layered bed was carried out,including the hydrogen purity and recovery.The simulation results show that the hydrogen purification system based on the layered bed model can achieve hydrogen purity of 95.469% and hydrogen recovery of 83.219%.Moreover,a parametric study was carried out and its results show that reductions in feed flow rate and adsorption time result in an increase in hydrogen purity and a decrease in hydrogen recovery.A longer equalization time between the two adsorption beds can simultaneously increase the hydrogen purity and recovery.展开更多
Aiming at the characteristics of multi-stage and(extremely)small samples of the identification problem of key effectiveness indexes of weapon equipment system-of-systems(WESoS),a Bayesian intelligent identification an...Aiming at the characteristics of multi-stage and(extremely)small samples of the identification problem of key effectiveness indexes of weapon equipment system-of-systems(WESoS),a Bayesian intelligent identification and inference model for system effectiveness assessment indexes based on dynamic grey incidence is proposed.The method uses multi-layer Bayesian techniques,makes full use of historical statistics and empirical information,and determines the Bayesian estima-tion of the incidence degree of indexes,which effectively solves the difficulties of small sample size of effectiveness indexes and difficulty in obtaining incidence rules between indexes.Sec-ondly,The method quantifies the incidence relationship between evaluation indexes and combat effectiveness based on Bayesian posterior grey incidence,and then identifies key system effec-tiveness evaluation indexes.Finally,the proposed method is applied to a case of screening key effectiveness indexes of a missile defensive system,and the analysis results show that the proposed method can fuse multi-moment information and extract multi-stage key indexes,and has good data extraction capability in the case of small samples.展开更多
目的分析总结青少年起病的成人型糖尿病2型(maturity-onset diabetes of the young type 2,MODY2)患儿的临床表现及遗传学特点,提高临床工作中对MODY2的识别能力。方法回顾性分析2017年8月—2023年7月在华中科技大学同济医学院附属同济...目的分析总结青少年起病的成人型糖尿病2型(maturity-onset diabetes of the young type 2,MODY2)患儿的临床表现及遗传学特点,提高临床工作中对MODY2的识别能力。方法回顾性分析2017年8月—2023年7月在华中科技大学同济医学院附属同济医院儿科确诊的13例MODY2患儿的临床资料。结果13例MODY2患儿(编号P1~13)均有糖尿病家族史,均为健康体检或因感染性疾病偶然发现的轻度空腹高血糖[(6.4±0.5)mmol/L)]。其中2例空腹血糖达到糖尿病诊断标准,其他病例均为空腹血糖受损或糖耐量受损;1 h血糖(one-hour post-glucose,1-hPG)波动在8.31~13.06 mmol/L,已到达国际糖尿病联盟推荐的糖尿病诊断标准。13例MODY2患儿均为葡萄糖激酶(glucokinase,GCK)基因杂合变异,其中P6为GCK c.1047C>A(p.Y349X)、P11为GCK c.1146_1147insGCAGAGCGTGTCTACGCGCGCTGCGCACATGTGC(p.S383Alafs*87)和P13为GCK c.784_785insC(p.D262Alafs*13),均为尚未报道过的变异。结论该研究丰富了MODY2的基因变异谱;临床对于有糖尿病家族史、偶然发现的轻度空腹血糖增高、糖尿病相关抗体阴性的患儿,需警惕MODY2可能。展开更多
为全面分析常导高速磁浮线路轨道系统的研究进展,通过Web of Science、EI、中国知网与万方数据核心数据库检索获取1987~2023年321篇中英文相关文献,涵盖16个国家与地区和59个国内机构;首次利用文献计量方法并借助CiteSpace工具构建科学...为全面分析常导高速磁浮线路轨道系统的研究进展,通过Web of Science、EI、中国知网与万方数据核心数据库检索获取1987~2023年321篇中英文相关文献,涵盖16个国家与地区和59个国内机构;首次利用文献计量方法并借助CiteSpace工具构建科学知识图谱梳理常导高速磁浮线路轨道系统研究进展;基于文献时空分布特点,关键词共现、突现与聚类分析,对领域发展脉络、研究力量、研究主题与热点进行分析总结并可视化展示。研究结果表明:常导高速磁浮线路轨道系统研究经历了发展起步阶段、初步发展阶段,目前正处于高速发展阶段;领域研究热度与重要工程建设和政策支持呈正相关;中国是领域研究的中坚力量,所发表英文研究成果占总体的83.82%;研究核心机构以高校为主,与企业有紧密联系;研究主题主要围绕线路设计优化,轨道梁结构设计,轨道制造和安装技术研究,轨道静力学与动力学性能分析,环境荷载响应分析,系统耦合动力学响应分析,轨道结构检测、监测与维护等7个方向展开;从研究热点上看,以车轨耦合效应、轨道结构检测与监测为主,设计、制造和维护等方面的研究还略显不足。上述计量分析成果表明常导高速磁浮线路轨道系统研究还存在较大提升空间,中国新一代时速600 km高速磁浮交通发展将是提升该领域研究水平的良好契机。展开更多
构建数字孪生水利建设知识图谱挖掘水利建设对象之间的潜在关系能够帮助相关人员优化水利建设设计方案和决策。针对数字孪生水利建设的学科交叉和知识结构复杂的特性,以及通用知识抽取模型缺乏对水利领域知识的学习和知识抽取精度不足...构建数字孪生水利建设知识图谱挖掘水利建设对象之间的潜在关系能够帮助相关人员优化水利建设设计方案和决策。针对数字孪生水利建设的学科交叉和知识结构复杂的特性,以及通用知识抽取模型缺乏对水利领域知识的学习和知识抽取精度不足等问题,为提高知识抽取的精度,提出一种基于大语言模型的数字孪生水利建设知识抽取方法(DTKE-LLM)。该方法通过LangChain部署本地大语言模型(LLM)并集成数字孪生水利领域知识,基于提示学习微调LLM,LLM利用语义理解和生成能力抽取知识,同时,设计异源实体对齐策略优化实体抽取结果。在水利领域语料库上进行对比实验和消融实验,以验证所提方法的有效性。对比实验结果表明,相较于基于深度学习的双向长短期记忆条件随机场(BiLSTM-CRF)命名实体识别模型和通用信息抽取模型UIE(Universal Information Extraction),DTKE-LLM的精确率更优;消融实验结果表明,相较于ChatGLM2-6B(Chat Generative Language Model 2.6 Billion),DTKE-LLM的实体抽取和关系抽取F1值分别提高了5.5和3.2个百分点。可见,该方法在保障知识图谱构建质量的基础上,实现了数字孪生水利建设知识图谱的构建。展开更多
体系效能评估指标数量多、维数高,指标之间关联,且具有协同效应,加大了效能评估的计算复杂性。针对这一问题,建立考虑协同效应的联合作战体系效能指标灰色主成分分析(grey principal component analysis,GPCA)重构模型。首先,分析联合...体系效能评估指标数量多、维数高,指标之间关联,且具有协同效应,加大了效能评估的计算复杂性。针对这一问题,建立考虑协同效应的联合作战体系效能指标灰色主成分分析(grey principal component analysis,GPCA)重构模型。首先,分析联合防空作战体系的作战使命、任务、流程,构建其效能评估指标体系,并运用灰色关联模型分析指标间是否存在协同效应。其次,基于指标间存在的协同效应,给出3种重构效能评估指标体系的策略,并结合GPCA方法,构建具有协同效应的GPCA模型,对评估指标体系进行降维。最后,将所提方法应用于联合防空作战体系效能评估案例,筛选出具有协同效应的指标,重构效能评估指标体系。计算结果与方法对比分析表明,所提方法能够有效发现指标间的协同效应,重构后的评估指标体系保持了“同构性”。展开更多
基金Funded by the National Key R&D Program of China (No.2021YFB2601603)the National Natural Science Foundation of China (Nos. 52176191, 51476120)+2 种基金the Science and Technology Innovation Project of Jianghan University (No. 2021kjzx005)the 111 Project (No. B17034)the Innovative Research Team Development Program of the Ministry of Education of China (No. IRT_17R83)。
文摘A pressure swing adsorption (PSA) hydrogen purification model for the four-component gas (H_(2)/CO_(2)/CH_(4)/CO=73/16/8/3 mol%) in a layered bed packed with Cu-BTC and zeolite 5A was established to achieve better hydrogen purification performance.By comparing its simulation results with the experimental data,the adsorption isotherm model was validated and could be used to accurately describe the adsorption process of the gas mixture on the two adsorbents.The breakthrough curves of the mixed gas on the layered bed were studied to verify the correctness of the established simulation models.Based on the validated model,the performance of the PSA system based on the layered bed was carried out,including the hydrogen purity and recovery.The simulation results show that the hydrogen purification system based on the layered bed model can achieve hydrogen purity of 95.469% and hydrogen recovery of 83.219%.Moreover,a parametric study was carried out and its results show that reductions in feed flow rate and adsorption time result in an increase in hydrogen purity and a decrease in hydrogen recovery.A longer equalization time between the two adsorption beds can simultaneously increase the hydrogen purity and recovery.
基金supported by the National Natural Science Foundation of China(72271124,72071111).
文摘Aiming at the characteristics of multi-stage and(extremely)small samples of the identification problem of key effectiveness indexes of weapon equipment system-of-systems(WESoS),a Bayesian intelligent identification and inference model for system effectiveness assessment indexes based on dynamic grey incidence is proposed.The method uses multi-layer Bayesian techniques,makes full use of historical statistics and empirical information,and determines the Bayesian estima-tion of the incidence degree of indexes,which effectively solves the difficulties of small sample size of effectiveness indexes and difficulty in obtaining incidence rules between indexes.Sec-ondly,The method quantifies the incidence relationship between evaluation indexes and combat effectiveness based on Bayesian posterior grey incidence,and then identifies key system effec-tiveness evaluation indexes.Finally,the proposed method is applied to a case of screening key effectiveness indexes of a missile defensive system,and the analysis results show that the proposed method can fuse multi-moment information and extract multi-stage key indexes,and has good data extraction capability in the case of small samples.
文摘目的分析总结青少年起病的成人型糖尿病2型(maturity-onset diabetes of the young type 2,MODY2)患儿的临床表现及遗传学特点,提高临床工作中对MODY2的识别能力。方法回顾性分析2017年8月—2023年7月在华中科技大学同济医学院附属同济医院儿科确诊的13例MODY2患儿的临床资料。结果13例MODY2患儿(编号P1~13)均有糖尿病家族史,均为健康体检或因感染性疾病偶然发现的轻度空腹高血糖[(6.4±0.5)mmol/L)]。其中2例空腹血糖达到糖尿病诊断标准,其他病例均为空腹血糖受损或糖耐量受损;1 h血糖(one-hour post-glucose,1-hPG)波动在8.31~13.06 mmol/L,已到达国际糖尿病联盟推荐的糖尿病诊断标准。13例MODY2患儿均为葡萄糖激酶(glucokinase,GCK)基因杂合变异,其中P6为GCK c.1047C>A(p.Y349X)、P11为GCK c.1146_1147insGCAGAGCGTGTCTACGCGCGCTGCGCACATGTGC(p.S383Alafs*87)和P13为GCK c.784_785insC(p.D262Alafs*13),均为尚未报道过的变异。结论该研究丰富了MODY2的基因变异谱;临床对于有糖尿病家族史、偶然发现的轻度空腹血糖增高、糖尿病相关抗体阴性的患儿,需警惕MODY2可能。
文摘为全面分析常导高速磁浮线路轨道系统的研究进展,通过Web of Science、EI、中国知网与万方数据核心数据库检索获取1987~2023年321篇中英文相关文献,涵盖16个国家与地区和59个国内机构;首次利用文献计量方法并借助CiteSpace工具构建科学知识图谱梳理常导高速磁浮线路轨道系统研究进展;基于文献时空分布特点,关键词共现、突现与聚类分析,对领域发展脉络、研究力量、研究主题与热点进行分析总结并可视化展示。研究结果表明:常导高速磁浮线路轨道系统研究经历了发展起步阶段、初步发展阶段,目前正处于高速发展阶段;领域研究热度与重要工程建设和政策支持呈正相关;中国是领域研究的中坚力量,所发表英文研究成果占总体的83.82%;研究核心机构以高校为主,与企业有紧密联系;研究主题主要围绕线路设计优化,轨道梁结构设计,轨道制造和安装技术研究,轨道静力学与动力学性能分析,环境荷载响应分析,系统耦合动力学响应分析,轨道结构检测、监测与维护等7个方向展开;从研究热点上看,以车轨耦合效应、轨道结构检测与监测为主,设计、制造和维护等方面的研究还略显不足。上述计量分析成果表明常导高速磁浮线路轨道系统研究还存在较大提升空间,中国新一代时速600 km高速磁浮交通发展将是提升该领域研究水平的良好契机。
文摘构建数字孪生水利建设知识图谱挖掘水利建设对象之间的潜在关系能够帮助相关人员优化水利建设设计方案和决策。针对数字孪生水利建设的学科交叉和知识结构复杂的特性,以及通用知识抽取模型缺乏对水利领域知识的学习和知识抽取精度不足等问题,为提高知识抽取的精度,提出一种基于大语言模型的数字孪生水利建设知识抽取方法(DTKE-LLM)。该方法通过LangChain部署本地大语言模型(LLM)并集成数字孪生水利领域知识,基于提示学习微调LLM,LLM利用语义理解和生成能力抽取知识,同时,设计异源实体对齐策略优化实体抽取结果。在水利领域语料库上进行对比实验和消融实验,以验证所提方法的有效性。对比实验结果表明,相较于基于深度学习的双向长短期记忆条件随机场(BiLSTM-CRF)命名实体识别模型和通用信息抽取模型UIE(Universal Information Extraction),DTKE-LLM的精确率更优;消融实验结果表明,相较于ChatGLM2-6B(Chat Generative Language Model 2.6 Billion),DTKE-LLM的实体抽取和关系抽取F1值分别提高了5.5和3.2个百分点。可见,该方法在保障知识图谱构建质量的基础上,实现了数字孪生水利建设知识图谱的构建。
文摘体系效能评估指标数量多、维数高,指标之间关联,且具有协同效应,加大了效能评估的计算复杂性。针对这一问题,建立考虑协同效应的联合作战体系效能指标灰色主成分分析(grey principal component analysis,GPCA)重构模型。首先,分析联合防空作战体系的作战使命、任务、流程,构建其效能评估指标体系,并运用灰色关联模型分析指标间是否存在协同效应。其次,基于指标间存在的协同效应,给出3种重构效能评估指标体系的策略,并结合GPCA方法,构建具有协同效应的GPCA模型,对评估指标体系进行降维。最后,将所提方法应用于联合防空作战体系效能评估案例,筛选出具有协同效应的指标,重构效能评估指标体系。计算结果与方法对比分析表明,所提方法能够有效发现指标间的协同效应,重构后的评估指标体系保持了“同构性”。