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期刊论文 12

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CMA 1

伪收敛 1

卡尔曼滤波；多重统计相似度量；多样野值；定点迭代；状态估计 1

参数估计 1

可靠性工程 1

失效概率 1

新Bayes估计 1

时延估计 1

盲均衡 1

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Anovel approach of noise statistics estimate using H∞ filter in target tracking

Xie WANG,Mei-qin LIU,Zhen FAN,Sen-lin ZHANG

《信息与电子工程前沿（英文）》 2016年 第17卷 第5期   页码 449-457 doi: 10.1631/FITEE.1500262

摘要： Noise statistics are essential for estimation performance. In practical situations, however, a priori information of noise statistics is often imperfect. Previous work on noise statistics identification in linear systems still requires initial prior knowledge of the noise. A novel approach is presented in this paper to solve this paradox. First, we apply the H∞ filter to obtain the system state estimates without the common assumptions about the noise in conventional adaptive filters. Then by applying state estimates obtained from the H∞ filter, better estimates of the noise mean and covariance can be achieved, which can improve the performance of estimation. The proposed approach makes the best use of the system knowledge without a priori information with modest computation cost, which makes it possible to be applied online. Finally, numerical examples are presented to show the efficiency of this approach.

关键词： Noise estimate     H∞     filter     Target tracking    

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可靠性工程中参数的一种估计方法

韩明

《中国工程科学》 2003年 第5卷 第3期   页码 51-56

摘要：

提出了可靠性工程中参数的一种估计方法——新Bayes估计法，给出了失效概率、失效率的新Bayes估计的定义及其新Bayes估计。最后，结合实际问题的数据，进行了具体计算和分析，结果表明所提出的新Bayes估计法有效、可行，便于工程技术人员在工程中应用。

关键词： 可靠性工程     参数估计     新Bayes估计     失效概率    

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Development of an analytical model to estimate the churning losses in high-speed axial piston pumps

《机械工程前沿（英文）》 2022年 第17卷 第2期 doi: 10.1007/s11465-021-0671-1

摘要： The axial piston pumps in aerospace applications are often characterized by high-speed rotation to achieve great power density. However, their internal rotating parts are fully immersed in the casing oil during operation, leading to considerable churning losses (more than 10% of total power losses) at high rotational speeds. The churning losses deserve much attention at the design stage of high-speed axial piston pumps, but accurate analytical models are not available to estimate the drag torque associated with the churning losses. In this paper, we derive the analytical expressions of the drag torque acting on the key rotating parts immersed in oil, including the cylinder block and the multiple pistons in a circular array. The calculated drag torque agrees well with the experimental data over a wide range of rotational speeds from 1500 to 12000 r/min. The presented analytical model provides practical guidelines for reducing the churning losses in high-speed axial piston pumps or motors.

关键词： axial piston pump     rotating parts     high rotational speed     churning losses     drag torque    

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Fast scaling approach based on cavitation conditions to estimate the speed limitation for axial piston

Qun CHAO, Jianfeng TAO, Junbo LEI, Xiaoliang WEI, Chengliang LIU, Yuanhang WANG, Linghui MENG

《机械工程前沿（英文）》 2021年 第16卷 第1期   页码 176-185 doi: 10.1007/s11465-020-0616-0

摘要： The power density of axial piston pumps can benefit greatly from increased rotational speeds. However, the maximum rotational speed of axial piston machines is limited by the cavitation phenomenon for a given volumetric displacement. This paper presents a scaling law derived from an analytical cavitation model to estimate the speed limitations for the same series of axial piston pumps. The cavitation model is experimentally verified using a high-speed axial piston pump, and the scaling law is validated with open specification data in product brochures. Results show that the speed limitation is approximately proportional to the square root of the inlet pressure and inversely proportional to the cube root of volumetric displacement. Furthermore, a characteristic constant is defined based on the presented scaling law. This constant can represent the comprehensive capacity of axial piston pumps free from cavitation.

关键词： axial piston pump     cavitation     speed limitation     scaling law    

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The use of Artificial Neural Networks to estimate seismic damage and derive vulnerability functions for

Tiago Miguel FERREIRA, João ESTÊVÃO, Rui MAIO, Romeu VICENTE

《结构与土木工程前沿（英文）》 2020年 第14卷 第3期   页码 609-622 doi: 10.1007/s11709-020-0623-6

摘要： This paper discusses the adoption of Artificial Intelligence-based techniques to estimate seismic damage, not with the goal of replacing existing approaches, but as a mean to improve the precision of empirical methods. For such, damage data collected in the aftermath of the 1998 Azores earthquake (Portugal) is used to develop a comparative analysis between damage grades obtained resorting to a classic damage formulation and an innovative approach based on Artificial Neural Networks (ANNs). The analysis is carried out on the basis of a vulnerability index computed with a hybrid seismic vulnerability assessment methodology, which is subsequently used as input to both approaches. The results obtained are then compared with real post-earthquake damage observation and critically discussed taking into account the level of adjustment achieved by each approach. Finally, a computer routine that uses the ANN as an approximation function is developed and applied to derive a new vulnerability curve expression. In general terms, the ANN developed in this study allowed to obtain much better approximations than those achieved with the original vulnerability approach, which has revealed to be quite non-conservative. Similarly, the proposed vulnerability curve expression was found to provide a more accurate damage prediction than the traditional analytical expressions.

关键词： Artificial Neural Networks     seismic vulnerability     masonry buildings     damage estimation     vulnerability curves    

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A hybrid machine learning model to estimate self-compacting concrete compressive strength

Hai-Bang LY; Thuy-Anh NGUYEN; Binh Thai PHAM; May Huu NGUYEN

《结构与土木工程前沿（英文）》 2022年 第16卷 第8期   页码 990-1002 doi: 10.1007/s11709-022-0864-7

摘要： This study examined the feasibility of using the grey wolf optimizer (GWO) and artificial neural network (ANN) to predict the compressive strength (CS) of self-compacting concrete (SCC). The ANN-GWO model was created using 115 samples from different sources, taking into account nine key SCC factors. The validation of the proposed model was evaluated via six indices, including correlation coefficient (R), mean squared error, mean absolute error (MAE), IA, Slope, and mean absolute percentage error. In addition, the importance of the parameters affecting the CS of SCC was investigated utilizing partial dependence plots. The results proved that the proposed ANN-GWO algorithm is a reliable predictor for SCC’s CS. Following that, an examination of the parameters impacting the CS of SCC was provided.

关键词： artificial neural network     grey wolf optimize algorithm     compressive strength     self-compacting concrete    

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Suitability of common models to estimate hydrology and diffuse water pollution in North-eastern German

Muhammad WASEEM, Frauke KACHHOLZ, Jens TRÄNCKNER

《农业科学与工程前沿（英文）》 2018年 第5卷 第4期   页码 420-431 doi: 10.15302/J-FASE-2018243

摘要：

Various process-based models are extensively being used to analyze and forecast catchment hydrology and water quality. However, it is always important to select the appropriate hydrological and water quality modeling tools to predict and analyze the watershed and also consider their strengths and weaknesses. Different factors such as data availability, hydrological, hydraulic, and water quality processes and their desired level of complexity are crucial for selecting a plausible modeling tool. This review is focused on suitable model selection with a focus on desired hydrological, hydraulic and water quality processes (nitrogen fate and transport in surface, subsurface and groundwater bodies) by keeping in view the typical lowland catchments with intensive agricultural land use, higher groundwater tables, and decreased retention times due to the provision of artificial drainage. In this study, four different physically based, partially and fully distributed integrated water modeling tools, SWAT (soil and water assessment tool), SWIM (soil and water integrated model), HSPF (hydrological simulation program– FORTRAN) and a combination of tools from DHI (MIKE SHE coupled with MIKE 11 and ECO Lab), have been reviewed particularly for the Tollense River catchment located in North-eastern Germany. DHI combined tools and SWAT were more suitable for simulating the desired hydrological processes, but in the case of river hydraulics and water quality, the DHI family of tools has an edge due to their integrated coupling between MIKE SHE, MIKE 11 and ECO Lab. In case of SWAT, it needs to be coupled with another tool to model the hydraulics in the Tollense River as SWAT does not include backwater effects and provision of control structures. However, both SWAT and DHI tools are more data demanding in comparison to SWIM and HSPF. For studying nitrogen fate and transport in unsaturated, saturated, and river zone, HSPF was a better model to simulate the desired nitrogen transformation and transport processes. However, for nitrogen dynamics and transformations in shallow streams, ECO Lab had an edge due its flexibility for inclusion of user-desired water quality parameters and processes. In the case of SWIM, most of the input data and governing equations are similar to SWAT but it does not include water bodies (ponds and lakes), wetlands and drainage systems. In this review, only the processes that were needed to simulate the Tollense River catchment were considered, however the resulted model selection criteria can be generalized to other lowland catchments in Australia, North-western Europe and North America with similar complexity.

关键词： diffuse pollution     ECO Lab     HSPF     lowland catchment     MIKE 11     MIKE SHE     modeling tools     SWAT     SWIM     Tollense River     water quality    

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Maximum independent set in planning freight railway transportation

Gainanov Damir N., Mladenovic NENAD, Rasskazova V. A.

《工程管理前沿（英文）》 2018年 第5卷 第4期   页码 499-506 doi: 10.15302/J-FEM-2018031

摘要：

This work is devoted to the problem of planning of freight railway transportation. We define a special conflict graph on the basis of a set of acceptable train routes. The investigation aims to solve the classical combinatorial optimization problem in relation to the maximum independent set of vertices in undirected graphs. The level representation of the graph and its tree are introduced. With use of these constructions, the lower and upper bounds for the number of vertices in the maximum independent set are obtained.

关键词： independent set     algorithm     planning of transportation     two-sided estimate    

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一种新型多样野值鲁棒卡尔曼滤波器 Research Articles

黄玉龙,柏明明,张勇刚

《信息与电子工程前沿（英文）》 2022年 第23卷 第3期   页码 422-437 doi: 10.1631/FITEE.2000642

摘要： 针对线性离散随机系统，提出一种新型多样野值鲁棒卡尔曼滤波器（MORKF）。首先提出一种新的多重统计相似度来衡量两个随机向量各维度之间的相似性。然后，通过最大化基于多重统计相似度量的代价函数，得到所提出的MORKF。MORKF保证了迭代在弱约束下的收敛性，且本文从理论上分析了近似误差的有界性。给出了相似函数的选择策略，并与现有鲁棒方法进行比较。仿真结果验证了该滤波器的优越性。

关键词： 卡尔曼滤波；多重统计相似度量；多样野值；定点迭代；状态估计    

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一种新的用于3G互连的盲均衡改进算法TDE—CMA

汪　姬,胡爱群,宋宇波

《中国工程科学》 2007年 第9卷 第2期   页码 54-57

摘要：

　DVB中广泛使用的CMA均衡算法一直深受伪收敛问题的困扰。从CMA算法的代价函数、迭代方程 及初始化系数等方面对伪收敛问题进行研究，在此基础上提出一种带时延估计的CMA改进算法。该算法通过引 入时延校正因子来调整主径的位置，从而避免了伪收敛现象。计算机仿真表明该方法大大提高了原算法的收敛 性，并且具有运算量小、易实现的优点，是一种实用性较强的改进算法，适用于高速的３G互连应用。

关键词： 盲均衡     CMA     伪收敛     时延估计    

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Estimation of reproduction numbers of COVID-19 in typical countries and epidemic trends under different prevention and control scenarios

Chen Xu, Yinqiao Dong, Xiaoyue Yu, Huwen Wang, Lhakpa Tsamlag, Shuxian Zhang, Ruijie Chang, Zezhou Wang, Yuelin Yu, Rusi Long, Ying Wang, Gang Xu, Tian Shen, Suping Wang, Xinxin Zhang, Hui Wang, Yong Cai

《医学前沿（英文）》 2020年 第14卷 第5期   页码 613-622 doi: 10.1007/s11684-020-0787-4

摘要： The coronavirus disease 2019 (COVID-19) has become a life-threatening pandemic. The epidemic trends in different countries vary considerably due to different policy-making and resources mobilization. We calculated basic reproduction number (R ) and the time-varying estimate of the effective reproductive number (R ) of COVID-19 by using the maximum likelihood method and the sequential Bayesian method, respectively. European and North American countries possessed higher R and unsteady R fluctuations, whereas some heavily affected Asian countries showed relatively low R and declining R now. The numbers of patients in Africa and Latin America are still low, but the potential risk of huge outbreaks cannot be ignored. Three scenarios were then simulated, generating distinct outcomes by using SEIR (susceptible, exposed, infectious, and removed) model. First, evidence-based prompt responses yield lower transmission rate followed by decreasing R . Second, implementation of effective control policies at a relatively late stage, in spite of huge casualties at early phase, can still achieve containment and mitigation. Third, wisely taking advantage of the time-window for developing countries in Africa and Latin America to adopt adequate measures can save more people’s life. Our mathematical modeling provides evidence for international communities to develop sound design of containment and mitigation policies for COVID-19.

关键词： reproduction number     SEIR model     COVID-19     estimate    

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Phase- and epidemic region-adjusted estimation of the number of coronavirus disease 2019 cases in China

Ruijie Chang, Huwen Wang, Shuxian Zhang, Zezhou Wang, Yinqiao Dong, Lhakpa Tsamlag, Xiaoyue Yu, Chen Xu, Yuelin Yu, Rusi Long, Ning-Ning Liu, Qiao Chu, Ying Wang, Gang Xu, Tian Shen, Suping Wang, Xiaobei Deng, Jinyan Huang, Xinxin Zhang, Hui Wang, Yong Cai

《医学前沿（英文）》 2020年 第14卷 第2期   页码 199-209 doi: 10.1007/s11684-020-0768-7

摘要： The outbreak of the coronavirus disease 2019 was first reported in Wuhan in December 2019 and gradually spread to other areas in China. After implementation of prevention and control measures, the estimation of the epidemic trend is needed. A phase- and region-adjusted SEIR model was applied for modeling and predicting the number of cases in Wuhan, Hubei Province and regions outside Hubei Province in China. The estimated number of infections could reach its peak in late February 2020 in Wuhan and Hubei Province, which is 55 303–84 520 and 83 944–129 312, respectively, while the epidemic peaks in regions outside Hubei Province in China could appear on February 13, 2020 with the estimated 13 035–19 108 cases. According to the estimation, the outbreak would abate in March and April all over China. Current estimation provided evidence for planned work resumption under stringent prevention and control in China to further support the fight against the epidemic. Nevertheless, there is still possibility of the second outbreak brought by the work resumption and population migration, especially from Hubei Province and high intensity cities outside Hubei Province. Strict prevention and control measures still need to be considered in the regions with high intensity of epidemic and densely-populated cities.

关键词： SEIR model     COVID-19     estimate     China    

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标题 作者 时间 类型 操作

Anovel approach of noise statistics estimate using H∞ filter in target tracking

Xie WANG,Mei-qin LIU,Zhen FAN,Sen-lin ZHANG

期刊论文

可靠性工程中参数的一种估计方法

韩明

期刊论文

Development of an analytical model to estimate the churning losses in high-speed axial piston pumps

期刊论文

Fast scaling approach based on cavitation conditions to estimate the speed limitation for axial piston

Qun CHAO, Jianfeng TAO, Junbo LEI, Xiaoliang WEI, Chengliang LIU, Yuanhang WANG, Linghui MENG

期刊论文

The use of Artificial Neural Networks to estimate seismic damage and derive vulnerability functions for

Tiago Miguel FERREIRA, João ESTÊVÃO, Rui MAIO, Romeu VICENTE

期刊论文

A hybrid machine learning model to estimate self-compacting concrete compressive strength

Hai-Bang LY; Thuy-Anh NGUYEN; Binh Thai PHAM; May Huu NGUYEN

期刊论文

Suitability of common models to estimate hydrology and diffuse water pollution in North-eastern German

Muhammad WASEEM, Frauke KACHHOLZ, Jens TRÄNCKNER

期刊论文

Maximum independent set in planning freight railway transportation

Gainanov Damir N., Mladenovic NENAD, Rasskazova V. A.

期刊论文

一种新型多样野值鲁棒卡尔曼滤波器

黄玉龙,柏明明,张勇刚

期刊论文

一种新的用于3G互连的盲均衡改进算法TDE—CMA

汪　姬,胡爱群,宋宇波

期刊论文

Estimation of reproduction numbers of COVID-19 in typical countries and epidemic trends under different prevention and control scenarios

Chen Xu, Yinqiao Dong, Xiaoyue Yu, Huwen Wang, Lhakpa Tsamlag, Shuxian Zhang, Ruijie Chang, Zezhou Wang, Yuelin Yu, Rusi Long, Ying Wang, Gang Xu, Tian Shen, Suping Wang, Xinxin Zhang, Hui Wang, Yong Cai

期刊论文

Phase- and epidemic region-adjusted estimation of the number of coronavirus disease 2019 cases in China

Ruijie Chang, Huwen Wang, Shuxian Zhang, Zezhou Wang, Yinqiao Dong, Lhakpa Tsamlag, Xiaoyue Yu, Chen Xu, Yuelin Yu, Rusi Long, Ning-Ning Liu, Qiao Chu, Ying Wang, Gang Xu, Tian Shen, Suping Wang, Xiaobei Deng, Jinyan Huang, Xinxin Zhang, Hui Wang, Yong Cai

期刊论文