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Corrections for downhole NMR logging

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Petroleum Science 2012年第1期9卷 46-52页

作者： hu haitao Xiao Lizhi Wu Xiling State Key Laboratory of Petroleum Resource and Prospecting China University of PetroleumBeijing 102249China

Nuclear magnetic resonance logging （NMR） is an open well logging method. Drilling mud resistivity, formation resistivity and sodium ions influence its radio frequency （RF） field strength and NMR logging signals. Research on these effects can provide an important basis for NMR logging data acquisition and interpretation. Three models, water-based drilling mud--water bearing formation, water- based drilling mud--oil bearing formation, oil-based drilling mud--water bearing formation, were studied by finite element method numerical simulation. The influences of drilling mud resistivity and formation resistivity on the NMR logging tool RF field and the influences of sodium ions on the NMR logging signals were simulated numerically. On the basis of analysis, RF field correction and sodium ion correction formulae were proposed and their application range was also discussed. The results indicate that when drilling mud resistivity and formation resistivity are 0.02 Ω·m and 0.2 Ω·m respectively, the attenuation index of centric NMR logging tool is 8.9% and 9.47% respectively. The RF field of an eccentric NMR logging tool is affected mainly by formation resistivity. When formation resistivity is 0.1 Ω·m, the attenuation index is 17.5%. For centric NMR logging tools, the signals coming from sodium ions can be up to 31.8% of total signal. Suggestions are proposed for further research into NMR logging tool correction method and response characteristics.

关键词： NMR logging finite element method RF field NMR signal formation resistivity sodium ions

Multi-Layer Deep Sparse Representation for Biological Slice Image Inpainting

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Computers, Materials & Continua 2023年第9期76卷 3813-3832页

作者： haitao hu Hongmei Ma Shuli Mei College of Information and Electrical Engineering China Agricultural UniversityBeijing100000China Yantai Research Institute China Agricultural UniversityYantai264670China

Biological slices are an effective tool for studying the physiological structure and evolutionmechanism of biological ***,due to the complexity of preparation technology and the presence of many uncontrollable factors during the preparation processing,leads to problems such as difficulty in preparing slice images and breakage of slice ***,we proposed a biological slice image small-scale corruption inpainting algorithm with interpretability based on multi-layer deep sparse representation,achieving the high-fidelity reconstruction of slice *** further discussed the relationship between deep convolutional neural networks and sparse representation,ensuring the high-fidelity characteristic of the algorithm first.A novel deep wavelet dictionary is proposed that can better obtain image prior and possess learnable *** multi-layer deep sparse representation is used to implement dictionary learning,acquiring better signal *** with methods such as NLABH,Shearlet,Partial Differential Equation(PDE),K-Singular Value Decomposition(K-SVD),Convolutional Sparse Coding,and Deep Image Prior,the proposed algorithm has better subjective reconstruction and objective evaluation with small-scale image data,which realized high-fidelity inpainting,under the condition of small-scale image *** theOn2-level time complexitymakes the proposed algorithm *** proposed algorithm can be effectively extended to other cross-sectional image inpainting problems,such as magnetic resonance images,and computed tomography images.

关键词： Deep sparse representation image inpainting convolutional sparse modelling deep neural network

Analysis of rail potential and stray current in MVDC railway electrification system

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Railway Engineering Science 2021年第4期29卷 394-407页

作者： Salman Aatif haitao hu Fezan Rafiq Zhengyou He School of Electrical Engineering Southwest Jiaotong UniversityChengdu 610031China Department of Electrical Engineering(Bannu Campus) University of Engineering and Technology PeshawarPeshawarPakistan Department of Electrical Engineering NED University of Engineering and Technology KarachiKarachiPakistan

In contrast to the conventional direct current railway electrification system(DC-RES),the medium voltage direct current(MVDC)-RES is considered promising for long-distance high-speed *** the MVDC-RES,traction substations(TSSs)are placed much farther and train loads are much heavier than in the conventional ***,the MVDC-RES brings a drastic change in catenary voltage,TSS spacing,and train loading,which affects rail potential and stray *** this connection,this work performs some significant quantitative analysis of rail potential and stray current in the MVDC-RES *** MVDC simulation model is proposed and different grounding schemes are analyzed for a single-train and two TSSs scenario as well as for a multi-train multi-TSS sce*** to the simulation and analysis,the maximum values of rail potential and stray current at MVDC-RES distances and the maximum safe distance between adjacent TSSs are determined.

关键词： Railway electrification Medium voltage direct current(MVDC)railways Rail potential Stray current Stray corrosion

Adaptive droop control for better current-sharing in VSC-based MVDC railway electrification system

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Journal of Modern Power Systems and Clean Energy 2019年第4期7卷 962-974页

作者： Salman AATIF haitao hu Xiaowei YANG Yinbo GE Zhengyou HE Shibin GAO College of Electrical Engineering Southwest Jiaotong UniversityChengduChina National Rail Transit Electrification and Automation Engineering Technique Research Center Southwest Jiaotong UniversityChengduChina

The share of voltage source converter(VSC)technology is increasing in conventional power systems,and it is penetrating into specific transportation systems such as electric vehicles,railways,and *** are identifying feasible methods to improve the performance of railway electrification systems(RESs)by utilizing VSC-based medium-voltage direct current(MVDC)*** continuous motion of electric trains makes the catenary resistance a variable quantity,as compared to the traction substation(TSS),and affects the currentsharing behavior of the system.A modified droop control technique is proposed in this paper for VSC-based MVDC RES to provide more effective current-sharing while maintaining catenary voltages above the minimum allowable *** droop coefficient is selected through an exponential function based on the ratio between the concerned TSS current and the system average *** enables small adjustments of droop values in less concerning marginal current deviations,and provides higher droop adjustments for large current ***,the catenary voltages are regulated by considering the voltage data at the midpoint between two TSSs,which experiences the lowest voltages owing to the larger distance from the *** proposed techniques are validated via simulations and experiments.

关键词： Railway electrification Voltage source converter(VSC) Medium-voltage direct current(MVDC) Current-sharing Renewable energies in railways

A power-quality monitoring and assessment system for high-speed railways based on train-network-data center integration

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Railway Engineering Science 2021年第1期29卷 30-41页

作者： Jun Zhu haitao hu Zhengyou He Xiaomin Guo Weiguo Pan School of Electrical Engineering Southwest Jiaotong UniversityChengdu 610031China Beijing National Railway Research&Design Institute of Signal&Communication Group Co. LtdBeijing 100073China

In recent years,with the rapid development of high-speed railways(HSRs),power interruptions or disturbances in traction power supply systems have become increasingly ***,it is often impossible to detect these faults immediately through single-point monitoring or collecting data after *** coordinate the power quality data of both traction power supply systems(TPSSs)and high-speed trains(HSTs),a monitoring and assessing system is proposed to access the power quality issues on *** integrating train monitoring,traction substation monitoring and data center,this monitoring system not only realizes the real-time monitoring of operational behaviors for both TPSSs and HSTs,but also conducts a comprehensive assessment of operational quality for train-network *** on a large number of monitoring data,the field measurements show that this real-time monitoring system is effective for monitoring and evaluating a traction-network system.

关键词： High-speed railway Traction power supply system Power quality monitoring Data center

Identification of Green-Revertible Yellow 3(GRY3),encoding a 4-hydroxy-3-methylbut-2-enyl diphosphate reductase involved in chlorophyll synthesis under high temperature and high light in rice

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The Crop Journal 2023年第4期11卷 1171-1180页

作者： Hongzhen Jiang Anpeng Zhang Banpu Ruan haitao hu Rui Guo Jingguang Chen Qian Qian Zhenyu Gao China National Rice Research Institute Chinese Academy of Agricultural SciencesHangzhou 310006ZhejiangChina School of Agriculture Shenzhen Campus of Sun Yat-sen UniversityShenzhen 518107GuangdongChina Institute of Crop Breeding and Cultivation Shanghai Academy of Agricultural SciencesShanghai 201403China College of Life and Environmental Sciences Hangzhou Normal UniversityHangzhou 311121ZhejiangChina

Chlorophyll,a green pigment in photosynthetic organisms,is generated by two distinct biochemical pathways,the tetrapyrrole biosynthetic pathway(TBP) and the methylerythritol 4-phosphate(MEP)*** is one of the pathways for isoprenoid synthesis in plants,with 4-hydroxy-3-methylbut-2-enyl diphosphate reductase(HDR) catalyzing its last *** this study,we isolated a greenrevertible yellow leaf mutant gry3 in rice and cloned the GRY3 gene,which encodes a HDR participating in geranylgeranyl diphosphate(GGPP) biosynthesis in chloroplast.A complementation experiment confirmed that a missense mutation(C to T) in the fourth exon of LOC_Os03g52170 causes the gry3 *** high temperature and high light,transcript and protein abundances of GRY3 were reduced in the gry3 *** expression of chlorophyll biosynthesis,chloroplast development,and genes involved in photosynthesis were also *** reactive oxygen species accumulation,cell death,and photosynthetic proteins degradation were occurred in the *** content of GGPP was reduced in gry3 compared with Nipponbare,resulting in a stoichiometric imbalance of tetrapyrrolic chlorophyll *** results shed light on the response of chloroplast biogenesis and maintenance in plants to high-temperature and high-light stress.

关键词： Chloroplast High temperature High light Rice

Traction power systems for electrified railways:evolution,state of the art,and future trends

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Railway Engineering Science 2024年第1期32卷 1-19页

作者： haitao hu Yunjiang Liu Yong Li Zhengyou He Shibin Gao Xiaojuan Zhu Haidong Tao School of Electrical Engineering Southwest Jiaotong UniversityChengdu 610031China

Traction power systems(TPSs)play a vital role in the operation of electrified *** transformation of conventional railway TPSs to novel structures is not only a trend to promote the development of electrified railways toward high-efficiency and resilience but also an inevitable requirement to achieve carbon neutrality *** the basis of sorting out the power supply structures of conventional AC and DC modes,this paper first reviews the characteristics of the existing TPSs,such as weak power supply flexibility and low-energy ***,the power supply structures of various TPSs for future electrified railways are described in detail,which satisfy longer distance,low-carbon,high-efficiency,high-reliability and high-quality power supply ***,the application prospects of different traction modes are discussed from both technical and economic ***,this paper introduces the research progress of mixed-system electrified railways and traction power supply technologies without catenary system,speculates on the future development trends and challenges of TPSs and predicts that TPSs will be based on the continuous power supply mode,employing power electronic equipment and intelligent information technology to construct a railway comprehensive energy system with renewable energy.

关键词： Railway traction power system Future electrified railway Flexible continuous power supply Renewable energy Integrated energy system

Cognitive function correlations with apolipoprotein Eε4 single nucleotide polymorphism in 1000 elderly patients following general anesthesia A randomized controlled study

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Neural Regeneration Research 2009年第4期4卷 316-320页

作者： Yingmin Cai haitao hu Rongliang Xue Pengbin Liu Gaifeng Feng Weijiang Dong Bin Yu Minggang Zhao Department of Anesthesia Second Affiliated Hospital Medical College Xi'an Jiaotong University Xi'an 710004 Shaanxi Province China Department of Neuroanatomy Medical College Xi'an Jiaotong University Xi'an 710004 Shaanxi Province China Department of Forensic Medicine Medical College Xi'an Jiaotong University Xi'an 710004 Shaanxi Province China

BACKGROUND： Cognitive dysfunction occurs in elderly patients following general anesthesia, and this might be associated with genetics. Studies have shown that the ε4 allele gene is closely associated with senile dementia. OBJECTIVE： To compare and analyze the correlations between cognitive dysfunction and single nucleotide polymorphism of apolipoprotein E （ApoE） following inhalation or intravenous anesthesia. DESIGN, TIME AND SETTING： A randomized, controlled study was performed. The patients were recruited from the Department of Anesthesia, Second Affiliated Hospital, Medical College, Xi＇an Jiaotong University, China between May 2005 and December 2008. Genetic analyses were conducted at the Departments of Neuroanatomy and Forensic Medicine, Medical Corlege, Xi＇an Jiaotong University, China. PARTICIPANTS： A total of t 000 patients of ASA I-II grade, without genetic connection, were enrolled in this study, comprising 520 males and 480 females, aged （70.1± 4.6） years and weighing （57.3 ± 7.5） kg. No patients suffered from cognitive dysfunction. METHODS： The patients were equally and randomly divided into intravenous anesthesia and gas anesthesia groups. Total intravenous anesthesia and inhaled anesthesia were used. Genomic DNA from whole blood was extracted. The ApoE gene was amplified by PCR. Restriction fragment length polymorphism of ApoE gene was analyzed. Cognitive function was evaluated by Mini-Mental State Examination （MMSE）. Patients scoring 〈 25 points were diagnosed with cognitive dysfunction. MAIN OUTCOME MEASURES： Correlation of ApoE gene frequency and ApoE ε 4 allele to MMSE scores was measured. RESULTS： MMSE scores in patients from the gas anesthesia group significantly decreased 3 days after surgery, compared with the intravenous anesthesia group. The proportion of patients that scored 〈 25 points was significantly greater in the gas anesthesia group compared with the intravenous anesthesia group 3 days after surgery. Reduced MMSE scores closely correla

关键词： general anesthesia cognitive function apolipoprotein E polymorphism elderly

Genome-Wide Association Analysis and Allelic Mining of Grain Shape-Related Traits in Rice

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Rice science 2019年第6期26卷 384-392页

作者： LV Yang WANG Yueying Noushin JAHAN hu haitao CHEN Ping SHANG Lianguang LIN Haiyan DONG Guojun hu Jiang GAO Zhenyu QIAN Qian ZHANG Yu GUO Longbiao State Key Lab for Rice Biology China National Rice Research Institute Hangzhou 310006 China Tobacoo Research Institute Chinese Academy of Agricultural Sciences Qingdao 266101 China

Excavating single nucleotide polymorphisms (SNPs) significantly associated with rice grain shape and predicting candidate genes through genome-wide association study (GWAS) can provide a theoretical basis for discovery and utilization of excellent genetic resources in rice. Based on 16 352 SNPs, 161 natural indica rice varieties with various grain sizes in southern China were used for GWAS of grain shape-related traits, referring to grain length (GL), grain width (GW), 1000-grain weight (TGW), and grain length/width (GLW). Phenotypic statistics showed that coefficient of variation values for these four traits GL, GW, TGW and GLW were 9.92%, 9.09%, 20.20% and 16.38%, respectively. Each trait showed a normal distribution, and there was a certain correlation between these traits. Through general linear model correlation analysis, a total of 38 significant loci were identified, and a range of 100 kb upstream and downstream of the significant loci was identified as the candidate interval. On chromosome 3, GS3 and qGL3 were found to regulate GL. On chromosome 6, TGW6 and GW6a were found to regulate TGW. Also, some QTLs related to grain shape were found on chromosomes 5 and 9. Besides that, using sequenced 3K-germplasm resources, we found that there are 22 overlapped varieties between these two natural populations. Twenty-six SNPs and fourteen haplotypes were identified in five regions of GS3 genes. The detection of multiple candidate genes/QTLs within the candidate interval is beneficial for further excavation of superior rice genetic resources.

关键词： candidate gene grain shape genome-wide association study haplotype rice single nucleotide polymorphism