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Development of an artificial intelligence diagnostic model based on dynamic uncertain causality graph

Yang Jiao, Zhan Zhang, Ting Zhang, Wen Shi, Yan Zhu, Jie Hu, Qin Zhang

《医学前沿(英文)》 2020年 第14卷 第4期   页码 488-497 doi: 10.1007/s11684-020-0762-0

摘要: Dyspnea is one of the most common manifestations of patients with pulmonary disease, myocardial dysfunction, and neuromuscular disorder, among other conditions. Identifying the causes of dyspnea in clinical practice, especially for the general practitioner, remains a challenge. This pilot study aimed to develop a computer-aided tool for improving the efficiency of differential diagnosis. The disease set with dyspnea as the chief complaint was established on the basis of clinical experience and epidemiological data. Differential diagnosis approaches were established and optimized by clinical experts. The artificial intelligence (AI) diagnosis model was constructed according to the dynamic uncertain causality graph knowledge-based editor. Twenty-eight diseases and syndromes were included in the disease set. The model contained 132 variables of symptoms, signs, and serological and imaging parameters. Medical records from the electronic hospital records of Suining Central Hospital were randomly selected. A total of 202 discharged patients with dyspnea as the chief complaint were included for verification, in which the diagnoses of 195 cases were coincident with the record certified as correct. The overall diagnostic accuracy rate of the model was 96.5%. In conclusion, the diagnostic accuracy of the AI model is promising and may compensate for the limitation of medical experience.

关键词: knowledge representation     uncertain     causality     graphical model     artificial intelligence     diagnosis     dyspnea    

Simultaneous removal of NO and chlorobenzene on VO/TiO granular catalyst: Kinetic study and performance prediction

《环境科学与工程前沿(英文)》 2021年 第15卷 第4期 doi: 10.1007/s11783-020-1363-5

摘要:

• A V2O5/TiO2 granular catalyst for simultaneous removal of NO and chlorobenzene.

关键词: NOx     Chlorobenzene     Simultaneous removal     Kinetic study     Performance prediction     V2O5/TiO2     Graphical abstract    

迈向下一代视网膜神经假体——基于脉冲的视觉计算方法 Review

余肇飞, 刘健, 贾杉杉, 张祎晨, 郑雅菁, 田永鸿, 黄铁军

《工程(英文)》 2020年 第6卷 第4期   页码 449-461 doi: 10.1016/j.eng.2020.02.004

摘要:

神经假体是一种精准医疗设备,旨在以闭环的方式操纵大脑神经信号,接受来自外界环境刺激的同时,控制人脑或人体的某些部分。外界输入的信息可以在大脑中的神经元细胞中以毫秒量级处理运算。就视觉而言,视觉场景信息进入眼睛,经过视网膜神经细胞进行处理,以神经元脉冲的模式将其输出,发送至脑皮层,以进行进一步的计算。因此,视网膜神经假体感兴趣的神经信号是神经元脉冲。神经假体中的闭环计算包括两个阶段:将刺激信息编码为神经元信号和将神经元信号重新解码为刺激信息。在本文中,我们回顾了视觉计算模型最近取得的一些进展,着重介绍这些模型如何使用脉冲来分析包括静态图像和动态视频在内的自然场景。为了更好地理解视网膜中神经网络的计算原理,我们认为,有必要对视网膜构建一个超级网络环路,在此环路中,那些皮层神经网络所揭示的不同功能的网络模块,都可以应用于视网膜网络中。视网膜的不同组成部分,包括多种细胞类型和突触连接——化学突触和电突触(缝隙连接),使视网膜成为一个理想的神经网络,其能够适应人工智能中发展起来的计算技术,对视觉场景的编码和解码进行建模。因此,有必要构建一种整体系统的方法,利用神经脉冲进行视觉计算,推动下一代视网膜神经假体发展,构建新型人工视觉系统。

关键词: 视觉编码     视网膜     神经假体     脑-机接口     人工智能     深度学习     脉冲神经网络     概率图模型    

建筑环境智能监测与反馈系统——发展与应用 Article

耿阳, 张仲宸, 余娟, 陈洪钟, 周浩,林波荣, 庄惟敏

《工程(英文)》 2022年 第18卷 第11期   页码 218-231 doi: 10.1016/j.eng.2021.09.017

摘要:

室内环境质量对人们的健康和福祉有显著影响,环境参数的连续监测与用户反馈已成为建筑业和学术界普遍关注的问题之一。现有关于环境监测系统的研究大多关注于传感器精度与成本效益的提升,而忽略了环境与用户之间的交互作用。为此,本团队开发了一种建筑环境智能监测与反馈系统,即智能建筑环境监测器(IBEM),既解决了室内环境参数的高时空分辨率、大通量、精准监测难题,又实现了环境与用户之间的反馈交互和主客观数据的同步采集。在硬件层面,IBEM集成了温度、相对湿度、PM2.5、CO2及照度多类传感器,并通过结构和电路优化设计减小了传感器之间的相互干扰,其测试精度经过与标准仪器的比对实验得到了有效验证,结果显示IBEM与标准仪器的测量数据基本一致,相关性强、误差小(R2 > 0.97,拟合斜率介于1.01 和1.05 之间)。在软件层面,基于无线通信和云技术建立了Web 端和移动端的可视化平台与用户交互界面,形成了环境数据的信息流及环境数据与用户交互反馈的通路。目前,IBEM已在国内18 个城市的131 栋建筑中得到了广泛应用,测点数量共1188 个,典型应用场景包括了室内环境问题的靶向诊断、主客观环境数据的关联分析等。综上,IBEM为人居环境领域的学术研究和工程实践提供了重要技术支撑。

关键词: 室内环境质量     传感器     连续监测     图形用户界面     交互反馈    

Standard model of knowledge representation

Wensheng YIN

《机械工程前沿(英文)》 2016年 第11卷 第3期   页码 275-288 doi: 10.1007/s11465-016-0372-3

摘要:

Knowledge representation is the core of artificial intelligence research. Knowledge representation methods include predicate logic, semantic network, computer programming language, database, mathematical model, graphics language, natural language, etc. To establish the intrinsic link between various knowledge representation methods, a unified knowledge representation model is necessary. According to ontology, system theory, and control theory, a standard model of knowledge representation that reflects the change of the objective world is proposed. The model is composed of input, processing, and output. This knowledge representation method is not a contradiction to the traditional knowledge representation method. It can express knowledge in terms of multivariate and multidimensional. It can also express process knowledge, and at the same time, it has a strong ability to solve problems. In addition, the standard model of knowledge representation provides a way to solve problems of non-precision and inconsistent knowledge.

关键词: knowledge representation     standard model     ontology     system theory     control theory     multidimensional representation    

受限空间火灾模型研究进展

郑昕,袁宏永

《中国工程科学》 2004年 第6卷 第3期   页码 68-74

摘要:

火灾模型是从工程科学的角度出发,分析研究火灾的发生、发展,烟气蔓延以及火灾对周围环境诸如建筑设备、森林植被及大气环境等影响的数学模型。介绍了广泛应用于建筑物内部受限空间的场、区域、网模型以及经验模型的理论思想与数学方程,分析了4种模型在相应环境下应用的合理性,并对火灾模型的发展做出了展望。

关键词: 受限空间     场模型     区域模型     网模型     场区网模型     经验模型    

Elevated temperature creep model of parallel wire strands

《结构与土木工程前沿(英文)》   页码 1060-1071 doi: 10.1007/s11709-023-0981-y

摘要: Parallel wire strands (PWSs), which are widely used in prestressed steel structures, are typically in high-stress states. Under fire conditions, significant creep effects occur, reducing the prestress and influencing the mechanical behavior of PWSs. As there is no existing approach to analyze their creep behavior, this study experimentally investigated the elevated temperature creep model of PWSs. A charge-coupled camera system was incorporated to accurately obtain the deformation of the specimen during the elevated temperature creep test. It was concluded that the temperature level had a more significant effect on the creep strain than the stress level, and 450 °C was the key segment point where the creep rate varied significantly. By comparing the elevated temperature creep test results for PWSs and steel strands, it was found that the creep strain of PWSs was lower than that of steel strands at the same temperature and stress levels. The parameters in the general empirical formula, the Bailey–Norton model, and the composite time-hardening model were fitted based on the experimental results. By evaluating the accuracy and form of the models, the composite time-hardening model, which can simultaneously consider temperature, stress, and time, is recommended for use in the fire-resistance design of pre-tensioned structures with PWSs.

关键词: parallel wire strands     experimental study     elevated temperature creep model    

Impact of crude distillation unit model accuracy on refinery production planning

Gang FU, Pedro A. Castillo CASTILLO, Vladimir MAHALEC

《工程管理前沿(英文)》 2018年 第5卷 第2期   页码 195-201 doi: 10.15302/J-FEM-2017052

摘要: In this work, we examine the impact of crude distillation unit (CDU) model errors on the results of refinery-wide optimization for production planning or feedstock selection. We compare the swing cut+ bias CDU model with a recently developed hybrid CDU model (Fu et al., 2016). The hybrid CDU model computes material and energy balances, as well as product true boiling point (TBP) curves and bulk properties (e.g., sulfur % and cetane index, and other properties). Product TBP curves are predicted with an average error of 0.5% against rigorous simulation curves. Case studies of optimal operation computed using a planning model that is based on the swing cut+ bias CDU model and using a planning model that incorporates the hybrid CDU model are presented. Our results show that significant economic benefits can be obtained using accurate CDU models in refinery production planning.

关键词: impact of model accuracy on production planning     swing cut+ bias CDU model     hybrid CDU model     refinery feedstock selection optimization     optimization of refinery operation    

Test-driven verification/validation of model transformations

László LENGYEL,Hassan CHARAF

《信息与电子工程前沿(英文)》 2015年 第16卷 第2期   页码 85-97 doi: 10.1631/FITEE.1400111

摘要: Why is it important to verify/validate model transformations? The motivation is to improve the quality of the transformations, and therefore the quality of the generated software artifacts. Verified/validated model transformations make it possible to ensure certain properties of the generated software artifacts. In this way, verification/validation methods can guarantee different requirements stated by the actual domain against the generated/modified/optimized software products. For example, a verified/validated model transformation can ensure the preservation of certain properties during the model-to-model transformation. This paper emphasizes the necessity of methods that make model transformation verified/validated, discusses the different scenarios of model transformation verification and validation, and introduces the principles of a novel test-driven method for verifying/validating model transformations. We provide a solution that makes it possible to automatically generate test input models for model transformations. Furthermore, we collect and discuss the actual open issues in the field of verification/validation of model transformations.

关键词: Graph rewriting based model transformations     Verification/validation     Test-driven verification    

Digital twin-assisted gearbox dynamic model updating toward fault diagnosis

《机械工程前沿(英文)》 2023年 第18卷 第2期 doi: 10.1007/s11465-023-0748-0

摘要: One of the core challenges of intelligent fault diagnosis is that the diagnosis model requires numerous labeled training datasets to achieve satisfactory performance. Generating training data using a virtual model is a potential solution for addressing such a problem, and the construction of a high-fidelity virtual model is fundamental and critical for data generation. In this study, a digital twin-assisted dynamic model updating method for fault diagnosis is thus proposed to improve the fidelity and reliability of a virtual model, which can enhance the generated data quality. First, a virtual model is established to mirror the vibration response of a physical entity using a dynamic modeling method. Second, the modeling method is validated through a frequency analysis of the generated signal. Then, based on the signal similarity indicator, a physical–virtual signal interaction method is proposed to dynamically update the virtual model in which parameter sensitivity analysis, surrogate technique, and optimization algorithm are applied to increase the efficiency during the model updating. Finally, the proposed method is successfully applied to the dynamic model updating of a single-stage helical gearbox; the virtual data generated by this model can be used for gear fault diagnosis.

关键词: digital twin     gearbox     model construction     model updating     physical–virtual interaction    

Estimation of composite load model with aggregate induction motor dynamic load for an isolated hybrid

Nitin Kumar SAXENA,Ashwani Kumar SHARMA

《能源前沿(英文)》 2015年 第9卷 第4期   页码 472-485 doi: 10.1007/s11708-015-0373-7

摘要: It is well recognized that the voltage stability of a power system is affected by the load model and hence, to effectively analyze the reactive power compensation of an isolated hybrid wind-diesel based power system, the loads need to be considered along with the generators in a transient analysis. This paper gives a detailed mathematical modeling to compute the reactive power response with small voltage perturbation for composite load. The composite load is a combination of the static and dynamic load model. To develop this composite load model, the exponential load is used as a static load model and induction motors (IMs) are used as a dynamic load model. To analyze the dynamics of IM load, the fifth, third and first order model of IM are formulated and compared using differential equations solver in Matlab coding. Since the decentralized areas have many small consumers which may consist large numbers of IMs of small rating, it is not realistic to model either a single large rating unit or all small rating IMs together that are placed in the system. In place of using a single large rating IM, a group of motors are considered and then the aggregate model of IM is developed using the law of energy conservation. This aggregate model is used as a dynamic load model. For different simulation studies, especially in the area of voltage stability with reactive power compensation of an isolated hybrid power system, the transfer function of the composite load is required. The transfer function of the composite load is derived in this paper by successive derivation for the exponential model of static load and for the fifth and third order IM dynamic load model using state space model.

关键词: isolated hybrid power system (IHPS)     composite load model     static load     dynamic load     induction motor load model     aggregate load    

Initiation of Setaria as a model plant

Xianmin DIAO,James SCHNABLE,Jeffrey L. BENNETZEN,Jiayang LI

《农业科学与工程前沿(英文)》 2014年 第1卷 第1期   页码 16-20 doi: 10.15302/J-FASE-2014011

摘要: Model organisms such as Arabidopsis ( ) and rice ( ) have proven essential for efficient scientific discovery and development of new methods. With the diversity of plant lineages, some important processes such as C photosynthesis are not found in either Arabidopsis or rice, so new model species are needed. Due to their small diploid genomes, short life cycles, self-pollination, small adult statures and prolific seed production, domesticated foxtail millet ( ) and its wild ancestor, green foxtail ( ), have recently been proposed as novel model species for functional genomics of the Panicoideae, especially for study of C photosynthesis. This review outlines the development of these species as model organisms, and discusses current challenges and future potential of a Setaria model.

关键词: Setaria     foxtail millet     C4 photosynthesis     model organism    

A time−space porosity computational model for concrete under sulfate attack

《结构与土木工程前沿(英文)》 doi: 10.1007/s11709-023-0985-7

摘要: The deterioration of the microscopic pore structure of concrete under external sulfate attack (ESA) is a primary cause of degradation. Nevertheless, little effort has been invested in exploring the temporal and spatial development of the porosity of concrete under ESA. This study proposes a mechanical–chemical model to simulate the spatiotemporal distribution of the porosity. A relationship between the corrosion damage and amount of ettringite is proposed based on the theory of volume expansion. In addition, the expansion strain at the macro-scale is obtained using a stress analysis model of composite concentric sphere elements and the micromechanical mean-field approach. Finally, considering the influence of corrosion damage and cement hydration on the diffusion of sulfate ions, the expansion deformation and porosity space−time distribution are obtained using the finite difference method. The results demonstrate that the expansion strains calculated using the suggested model agree well with previously reported experimental results. Moreover, the tricalcium aluminate concentration, initial elastic modulus of cement paste, corrosion damage, and continuous hydration of cement significantly affect concrete under ESA. The proposed model can forecast and assess the porosity of concrete covers and provide a credible approach for determining the residual life of concrete structures under ESA.

关键词: expansion deformation     porosity     internal expansion stress     external sulfate attack     mechanical–chemical coupling model    

The Construction of Tetrahedral Model of Engineering Ethical Evaluation

Jin Wang

《工程管理前沿(英文)》 2014年 第1卷 第1期   页码 62-70 doi: 10.15302/J-FEM-2014009

摘要: To achieve greatprojects, great attention should be attached to ethical issues of engineering. But endless immoralities in the field of engineering expose the lack of attention and the ineffectiveness of implementation of engineering ethical evaluation. The “Mirror” and the "Lamp" — these two metaphors used by M. H. Abrams vividly expose the differences in people's way of understanding which inspires author's study of the model of engineering ethical evaluation. With four elements of the project —artifact, engineer, user and environment, a tetrahedral model of integrity, strong restoring force and high stability is built. While their roles and responsibilities differ, each has to demonstrate a commitment to professional and ethical standards. In this model, four "Lamps" — i. e, four elements of engineering — in four corners provide light while four "Mirrors" — the result of reflection of four elements — reflect whether the tetrahedral model can truthfully evaluate the level of engineering ethics. The combination of the "Lamps" and "Mirrors" illuminates engineering ethical evaluation and leads to a plurality of evaluation standards, while simultaneously fostering both the avoidance of simple de-instrumentalization and the sustainability of ethical evaluation. Plurality of evaluation standards means the consideration of value differences in a multi-value state. The avoidance of de-instrumentalization means to prevent the engineer's expertise from fossilization. The sustainability of ethical evaluation accelerates the fulfillment of our dream, for the ultimate benefit of humankind. Ethical evaluation of the project not only helps more engineers to use expertise in pursuit of the public good, but also make more projects to meet people's short-term expectations and long-term cares.

关键词: tetrahedral model     ethical evaluation     engineering     Lamps and Mirrors    

标题 作者 时间 类型 操作

Development of an artificial intelligence diagnostic model based on dynamic uncertain causality graph

Yang Jiao, Zhan Zhang, Ting Zhang, Wen Shi, Yan Zhu, Jie Hu, Qin Zhang

期刊论文

Simultaneous removal of NO and chlorobenzene on VO/TiO granular catalyst: Kinetic study and performance prediction

期刊论文

迈向下一代视网膜神经假体——基于脉冲的视觉计算方法

余肇飞, 刘健, 贾杉杉, 张祎晨, 郑雅菁, 田永鸿, 黄铁军

期刊论文

建筑环境智能监测与反馈系统——发展与应用

耿阳, 张仲宸, 余娟, 陈洪钟, 周浩,林波荣, 庄惟敏

期刊论文

Standard model of knowledge representation

Wensheng YIN

期刊论文

张正彦:融合知识的预训练语言模型(2020年4月3日)

2022年04月18日

会议视频

受限空间火灾模型研究进展

郑昕,袁宏永

期刊论文

Elevated temperature creep model of parallel wire strands

期刊论文

Impact of crude distillation unit model accuracy on refinery production planning

Gang FU, Pedro A. Castillo CASTILLO, Vladimir MAHALEC

期刊论文

Test-driven verification/validation of model transformations

László LENGYEL,Hassan CHARAF

期刊论文

Digital twin-assisted gearbox dynamic model updating toward fault diagnosis

期刊论文

Estimation of composite load model with aggregate induction motor dynamic load for an isolated hybrid

Nitin Kumar SAXENA,Ashwani Kumar SHARMA

期刊论文

Initiation of Setaria as a model plant

Xianmin DIAO,James SCHNABLE,Jeffrey L. BENNETZEN,Jiayang LI

期刊论文

A time−space porosity computational model for concrete under sulfate attack

期刊论文

The Construction of Tetrahedral Model of Engineering Ethical Evaluation

Jin Wang

期刊论文