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Journal of Environmental Sciences 2021年第1期33卷 143-150页

作者： Jian Zhou xiaoxia han Boqiang Qin Guangwei Zhu Taihu Laboratory for Lake Ecosystem Research State Key Laboratory of Lake Science and EnuvironmentNanjing Institute of Geography and LimnologyChinese Academy of SciencesNanjing 210008China Laboratory and Analytical Testing Center Jiangsu Academy of Enuironmental Sciences Environmental Technology Co.LtdNanjing 210036China School of Geography and Ocean Science Nanjing UniversityNanjing 210023China

Phosphorus is a vital nutrient for algal growth,thus,a better understanding of phosphorus availability is essential to mitigate harmful algal blooms in *** waves are a ubiquitous characteristic of lake ***,its effects on the cycling of organic phosphorus and its usage by phytoplankton remain poorly elucidated in shallow eutrophic lakes.A mesocosm experiment was carried out to investigate the responses of alkaline phosphatase activity fractions to wind waves in large,shallow,eutrophic Lake *** showed that wind-driven waves induced the release of alkaline phosphatase and phosphorus from the sediment,and dramatically enhanced phytoplanktonic alkaline phosphatase ***,compared to the calm conditions,bacterial and dissolved alkaline phosphatase activity decreased in wind-wave ***,the gene copies of Microcystis phoX increased but bacterial phoX decreased under wind-wave *** ecological effects of these waves on phosphorus and phytoplankton likely accelerated the biogeochemical cycling of phosphorus and promoted phytoplankton production in Lake *** study provides an improved current understanding of phosphorus availability and the phosphorus strategies of plankton in shallow,eutrophic lakes.

关键词： Wind waves Alkaline phosphatase activity Phosphorus Plankton phoX

A New Safety Assessment Method Based on Belief Rule Base With Attribute Reliability

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IEEE/CAA Journal of Automatica Sinica 2021年第11期8卷 1774-1785页

作者： Zhichao Feng Wei He Zhijie Zhou Xiaojun Ban Changhua Hu xiaoxia han Rocket Force University of Engineering Xi’an 710025China Harbin Normal University Harbin 150080China Harbin Institute of Technology Harbin 150001China

Safety assessment is one of important aspects in health *** safety assessment for practical systems,three problems exist:lack of observation information,high system complexity and environment *** rule base with attribute reliability(BRB-r)is an expert system that provides a useful way for dealing with these three *** BRB-r,once the input information is unreliable,the reliability of belief rule is influenced,which further influences the accuracy of its output belief *** the other hand,when many system characteristics exist,the belief rule combination will explode in BRB-r,and the BRB-r based safety assessment model becomes too complicated to be ***,in this paper,to balance the complexity and accuracy of the safety assessment model,a new safety assessment model based on BRB-r with considering belief rule reliability is developed for the first *** the developed model,a new calculation method of the belief rule reliability is proposed with considering both attribute reliability and global ***,to reduce the influence of uncertainty of expert knowledge,an optimization model for the developed safety assessment model is constructed.A case study of safety assessment of liquefied natural gas(LNG)storage tank is conducted to illustrate the effectiveness of the new developed model.

关键词： Belief rule base(BRB) belief rule reduction reliability safety assessment structure adjustment

A hidden fault prediction model based on the belief rule base with power set and considering attribute reliability

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Science China(Information Sciences) 2019年第10期62卷 86-101页

作者： Zhijie ZHOU Zhichao FENG Changhua HU xiaoxia han Zhiguo ZHOU Gailing LI High-Tech Institute of Xi'an Department of Radiation Oncology The University of Texas Southwestern Medical Center

Hidden faults are important characteristics of complex systems that cannot be observed *** hidden behavior of a system, such as the health state and safety level, has a direct correlation with these hidden faults. After the predicted hidden behavior reaches a fault boundary, certain measures must be taken to avoid fault occurrences. Thus, hidden faults can be predicted by the hidden behavior of a *** belief rule base(BRB) has been used to predict hidden behaviors. However, two problems remain to be solved in engineering practice. First, when the observed information is absent, ignorance may exist in the output. If only global ignorance is considered, it may be unreasonable in certain cases, which can influence the prediction model. Second, the effects of disturbance factors such as noise and sensor quality may cause the reliability of the gathered information to decline, which indirectly leads to unreliability of the hidden behavior. Thus, to address the global ignorance and unreliable hidden behavior, a new hidden BRB model with a power set and considering attribute reliability(PHBRB-r) is proposed for hidden fault prediction. In the PHBRB-r model, the effects of disturbance factors on hidden behavior are considered using attribute reliability, and the discernment frame is a power set. A case study of hidden fault prediction is conducted to demonstrate the effectiveness of the PHBRB-r model.

关键词： fault diagnosis fault prediction belief rule base hidden behavior attribute reliability power set

A new interpretable fault diagnosis method based on belief rule base and probability table

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Chinese Journal of Aeronautics 2023年第3期36卷 184-201页

作者： Zhichao MING Zhijie ZHOU You CAO Shuaiwen TANG Yuan CHEN xiaoxia han Wei HE High-Tech Institute of Xi’an Xi’an 710025China School of Computer Science and Information Engineering Harbin Normal UniversityHarbin 150025China

It is vital to establish an interpretable fault diagnosis model for critical *** Rule Base(BRB)is an interpretable expert system gradually applied in fault ***,the expert knowledge cannot be utilized to establish the initial BRB accurately if there are multiple referential grades in different fault *** addition,the interpretability of BRB-based fault diagnosis is destroyed in the optimization process,which reflects in two aspects:deviation from the initial expert judgment and over-optimization of *** solve these problems,a new interpretable fault diagnosis model based on BRB and probability table,called the BRB-P,is proposed in this *** with the traditional BRB,the BRB-P constructed by the probability table is more ***,the interpretability constraints,i.e.,the credibility of expert knowledge,the penalty factor and the rule-activation factor,are inserted into the projection covariance matrix adaption evolution strategy to maintain the interpretability of BRB-P.A case study of the aerospace relay is conducted to verify the effectiveness of the proposed method.

关键词： Aerospace relay Belief rule base Expert knowledge Fault diagnosis Interpretability constraints

A low power V-band LC VCO with high Q varactor technique in 40 nm CMOS process

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Science China(Information Sciences) 2017年第8期60卷 252-254页

作者： Qian ZHOU Yan han Shifeng ZhanG xiaoxia han Lu JIE Ray C.C.CHEUNG Guangtao FENG College of Information Science and Electronic Engineering Zhejiang University Department of Electronic Engineering City University of Hong Kong Semiconductor Manufacturing International Corporation

Dear editor,Demand for higher data transmission rate,particularly in the modern communication systems,has been increasing over the *** example,the IEEE standard 802.15.3c specifies more than2 Gbps data transmission rate,which pushes the frequency band up to 60 *** the transceiver,the working frequency of VCO is in 60 GHz,and that has attracted many people to study it[1,2].However,implementing high speed voltagecontrolled oscillator(VCO)through CMOS technology can be extremely challenging because of the

关键词： VCO A low power V-band LC VCO with high Q varactor technique in 40 nm CMOS process CMOS in high nm LC with

A Novel Belief Rule-Based Fault Diagnosis Method with Interpretability

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Computer Modeling in Engineering & Sciences 2023年第8期136卷 1165-1185页

作者： Zhijie Zhou Zhichao Ming Jie Wang Shuaiwen Tang You Cao xiaoxia han Gang Xiang Rocket Force University of Engineering Xi’an710025China School of Automation Science and Electrical Engineering Beihang UniversityBeijing100191China Beijing Aerospace Automatic Control Institute Beijing100070China

Fault diagnosis plays an irreplaceable role in the normal operation of equipment.A fault diagnosis model is often required to be interpretable for increasing the trust between humans and the *** to the understandable knowledge expression and transparent reasoning process,the belief rule base(BRB)has extensive applications as an interpretable expert system in fault *** is an effective means to weaken the subjectivity of experts in BRB,where the interpretability of BRB may be ***,to obtain a credible result,the weakening factors of interpretability in the BRB-based fault diagnosis model are firstly analyzed,which are manifested in deviation from the initial judgement of experts and over-optimization of *** these two factors,three indexes are proposed,namely the consistency index of rules,consistency index of the rule base and over-optimization index,tomeasure the interpretability of the *** both the accuracy and interpretability of amodel,an improved coordinate ascent(I-CA)algorithmis proposed to fine-tune the parameters of the fault diagnosis model based on *** I-CA,the algorithm combined with the advance and retreat method and the golden section method is employed to be one-dimensional search ***,the random optimization sequence and adaptive step size are proposed to improve the accuracy of the ***,a case study of fault diagnosis in aerospace relays based on BRB is carried out to verify the effectiveness of the proposed method.

关键词： Fault diagnosis belief rule base interpretability weakening factors improved coordinate ascent

A 65-nm low-noise low-costΣ△modulator for audio applications

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Journal of Semiconductors 2012年第2期33卷 82-86页

作者： Liang Guo Liao Lu Luo Hao Liu Xiaopeng han xiaoxia han Yan Institute of Microelectronics&Photoelectronics Zhejiang UniversityHangzhou 310027China

This paper introduces a low-noise low-costΣA modulator for digital audio analog-to-digital conversion. By adopting a low-noise large-output swing operation amplifier,not only is the flicker noise greatly inhibited,but also the power consumption is *** the area cost is relatively *** modulator was implemented in a SMIC standard 65-nm CMOS *** results show it can achieve 96 dB peak signal-to-noise plus distortion ratio（SNDR） and 105 dB dynamic range（DR） over the 22.05-kHz audio band and occupies 0.16 mm^2. The power consumption of the proposed modulator is 4.9 mW from a 2.5 V power supply,which is suitable for high-performance,low-cost audio codec applications.

关键词： Σ△modulator low-noise low-cost analog-to-digital converter

On Statistical Measures for Data Quality Evaluation

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Journal of Geographic Information System 2020年第3期12卷 178-187页

作者： xiaoxia han Department of Public Health Sciences Henry Ford Health System Detroit USA

Most GIS databases contain data errors. The quality of the data sources such as traditional paper maps or more recent remote sensing data determines spatial data quality. In the past several decades, different statistical measures have been developed to evaluate data quality for different types of data, such as nominal categorical data, ordinal categorical data and numerical data. Although these methods were originally proposed for medical research or psychological research, they have been widely used to evaluate spatial data quality. In this paper, we first review statistical methods for evaluating data quality, discuss under what conditions we should use them and how to interpret the results, followed by a brief discussion of statistical software and packages that can be used to compute these data quality measures.

关键词： GIS Data Quality Sensitivity Specificity Kappa Weighted Kappa Bland-Altman Analysis Intra-Class Correlation Coefficient

A Health State Prediction Model Based on Belief Rule Base and LSTM for Complex Systems

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Intelligent Automation & Soft Computing 2024年第1期39卷 73-91页

作者： Yu Zhao Zhijie Zhou Hongdong Fan xiaoxia han JieWang Manlin Chen High-Tech Institute of Xi’an Xi’an710025China

In industrial production and engineering operations,the health state of complex systems is critical,and predicting it can ensure normal *** systems have many monitoring indicators,complex coupling structures,non-linear and time-varying characteristics,so it is a challenge to establish a reliable prediction *** belief rule base(BRB)can fuse observed data and expert knowledge to establish a nonlinear relationship between input and output and has well modeling *** each indicator of the complex system can reflect the health state to some extent,the BRB is built based on the causal relationship between system indicators and the health state to achieve the prediction.A health state prediction model based on BRB and long short term memory for complex systems is proposed in this ***,the LSTMis introduced to predict the trend of the indicators in the ***,the Density Peak Clustering(DPC)algorithmis used todetermine referential values of indicators for BRB,which effectively offset the lack of expert ***,the predicted values and expert knowledge are fused to construct BRB to predict the health state of the systems by ***,the effectiveness of the model is verified by a case study of a certain vehicle hydraulic pump.

关键词： Health state predicftion complex systems belief rule base expert knowledge LSTM density peak clustering

Genome-Wide Likelihood Ratio Tests under Heterogeneity

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Open Journal of Statistics 2018年第3期8卷 468-478页

作者： xiaoxia han Yongzhao Shao Public Health Sciences Department Henry Ford Health System Detroit MI USA Department of Population Health New York University School of Medicine New York NY USA

The commonly used statistical methods in medical research generally assume patients arise from one homogeneous population. However, the existence and importance of significant heterogeneity have been widely documented. It is well known that common and complex human diseases usually have heterogeneous disease etiology, which often involves interplay of multiple genetic and environmental factors, leading to latent population substructure. Genome-wide association studies (GWAS) is a useful tool to uncover genetic association with disease of interest, while linkage analysis is a commonly used method to identify statistical association between the inheritance of a human disease and inheritance of marker loci that are in linkage with disease causing loci. We propose a likelihood ratio test for genome-wide linkage analysis under genetic heterogeneity using family data. We derive a closed-form formula for the LRT test statistic and provide explicit asymptotic null distribution. The closed form asymptotic distribution allows easy determination of the asymptotic p-values. Our extensive simulation studies indicate that the proposed test has proper type I error and good power under genetic heterogeneity. In order to simplify application of the proposed method for non-statisticians, we develop an R package gLRTH to implement the proposed LRT for genome-wide linkage analysis as well as Qian and Shao’s LRT for GWAS under heterogeneity. The newly developed open source R package gLRTH is available at CRAN.

关键词： Genetic Heterogeneity Transmission Heterogeneity Complex Disease Genome-Wide Association Study Genetic Linkage Analysis R Software Package