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Interpretation and characterization of rate of penetration intelligent prediction model

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Petroleum Science 2024年第1期21卷 582-596页

作者： Zhi-Jun Pei xian-Zhi song Hai-tao Wang Yi-Qi Shi Shou-Ceng Tian Gen-Sheng Li College of Petroleum Engineering China University of Petroleum(Beijing)Beijing102249China State Key Laboratory of Petroleum Resources and Prospecting Beijing102249China Kunlun Digital Technology Co. Ltd.Beijing102206China

Accurate prediction of the rate of penetration(ROP)is significant for drilling *** the intelligent ROP prediction model based on fully connected neural networks(FNN)outperforms traditional ROP equations and machine learning algorithms,its lack of interpretability undermines its *** study proposes a novel interpretation and characterization method for the FNN ROP prediction model using the Rectified Linear Unit(ReLU)activation *** leveraging the derivative of the ReLU function,the FNN function calculation process is transformed into vector *** FNN model is linearly characterized through further simplification,enabling its interpretation and *** proposed method is applied in ROP prediction scenarios using drilling data from three vertical wells in the Tarim *** results demonstrate that the FNN ROP prediction model with ReLU as the activation function performs exceptionally *** relative activation frequency curve of hidden layer neurons aids in analyzing the overfitting of the FNN ROP model and determining drilling data *** the well sections with similar drilling data,averaging the weight parameters enables linear characterization of the FNN ROP prediction model,leading to the establishment of a corresponding linear representation ***,the quantitative analysis of each feature's influence on ROP facilitates the proposal of drilling parameter optimization schemes for the current well *** established linear characterization equation exhibits high precision,strong stability,and adaptability through the application and validation across multiple well sections.

关键词： Fully connected neural network Explainable artificial intelligence Rate of penetration ReLU active function Deep learning Machine learning

Relationship between coronary artery remodeling and cumulative incidence of coronary angiographic lesions with vulnerable characteristics in patients with stable angina pectoris

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Chinese Medical Journal 2010年第7期123卷 871-876页

作者： SUN Ling Lü Shu-zheng JIN Ze-ning song xian-tao Department of Cardiology Fushun Central Hospital FushunLiaoning 113006 China Department of Cardiology Beijing Anzhen Hospital Capital Medical University Beijing 100029 China

ackground Development of vulnerable lesions is not limited to the target lesions, but a pan-coronary process. Such lesions are identified by positive remodeling （intravascular ultrasound （IVUS） and complex lesions （angiography））. The prevalence of lesions with vulnerable characteristics in patients with stable angina was not well known. The purpose of the present study was to evaluate the relationship between coronary artery remodeling and incidence of angiographic complex lesions and its calcification in stable angina *** One hundred and sixty-one stable angina patients （95 males, aged （68±11） years） with 161 de novo target lesions were studied using pre-interventional IVUS. Remodeling index was defined as the lesion divided by reference vessel area; positive remodeling was defined as remodeling index 〉1.05. Besides the 161 target lesions, there were 613 angiographic lesions with 〉30% diameter stenoses, classified as complex or smooth. Multiple complexes were defined as more than one complex lesion in one patient. Stenoses of at least 70% were described as tight. Calcium arc area was used as a new method to quantify coronary *** Fifty-six patients had positive remodeling target lesion, while 105 did not. The overall number of lesions with a diameter stenoses 〉30% was similar in patients with or without positive remodeling, and the frequency of angiographically complex lesions was higher in positive remodeling patients, especially at non-target site. Calcium arc area was smaller in patients with positive *** Positive remodeling on intravascular ultrasound was associated with more complex lesions angiographic findings, especially at non target site. Positive remodeling was found less calcified in patients with stable angina.

关键词： intravascular ultrasound complex lesion positive remodeling stable angina pectoris calcium arc area

Minimalistic approach to left atrial appendage occlusion guided by cardiac computed tomography angiography

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Journal of Geriatric Cardiology 2024年第4期21卷 431-442页

作者： xian-Sai MENG Qing-song WANG Xin-Yan WANG Xu LU Yang MU Jing WANG Ting-Ting song Yun-Dai CHEN tao CHEN Jun GUO Graduate School of Chinese PLA Medical College BeijingChina Senior Department of Cardiology the Sixth Med-ical CenterChinese PLA General HospitalBeijingChina

OBJECTIVE To assess the feasibility and safety of the minimalistic approach to left atrial appendage occlusion(LAAO) guided by cardiac computed tomography angiography(CCTA).METHODS Ninety consecutive patients who underwent LAAO, with or without CCTA-guided, were matched(1:2). Each step of the LAAO procedure in the computed tomography(CT) guidance group(CT group) was directed by preprocedural CT planning. In the control group, LAAO was performed using the standard method. All patients were followed up for 12 months, and device surveillance was conducted using *** A total of 90 patients were included in the analysis, with 30 patients in the CT group and 60 matched patients in the control group. All patients were successfully implanted with Watchman devices. The mean ages for the CT group and the control group were 70.0 ± 9.4 years and 68.4 ± 11.9 years(P = 0.52), respectively. The procedure duration(45.6 ± 10.7 min vs. 58.8 ± 13.0 min,P < 0.001) and hospital stay(7.5 ± 2.4 day vs. 9.6 ± 2.8 day, P = 0.001) in the CT group was significantly shorter compared to the control group. However, the total radiation dose was higher in the CT group compared to the control group(904.9 ± 348.0 m Gy vs.711.9 ± 211.2 m Gy, P = 0.002). There were no significant differences in periprocedural pericardial effusion(3.3% vs. 6.3%, P = 0.8) between the two groups. The rate of postprocedural adverse events(13.3% vs. 18.3%, P = 0.55) were comparable between both groups at 12 months *** CCTA is capable of detailed LAAO procedure planning. Minimalistic LAAO with preprocedural CCTA planning was feasible and safe, with shortened procedure time and acceptable increased radiation and contras consumption. For patients with contraindications to general anesthesia and/or transesophageal echocardiography, this promising method may be an alternative to conventional LAAO.

关键词： anesthesia matched approach

Hierarchical multihead self-attention for time-series-based fault diagnosis

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Chinese Journal of Chemical Engineering 2024年第6期70卷 104-117页

作者： Chengtian Wang Hongbo Shi Bing song Yang tao Key Laboratory of Smart Manufacturing in Energy Chemical Process of the Ministry of Education East China University of Science and TechnologyShanghai 200237China

Fault diagnosis is important for maintaining the safety and effectiveness of chemical *** the multivariate,nonlinear,and dynamic characteristic of chemical process,many time-series-based data-driven fault diagnosis methods have been developed in recent ***,the existing methods have the problem of long-term dependency and are difficult to train due to the sequential way of *** overcome these problems,a novel fault diagnosis method based on time-series and the hierarchical multihead self-attention(HMSAN)is proposed for chemical ***,a sliding window strategy is adopted to construct the normalized time-series ***,the HMSAN is developed to extract the time-relevant features from the time-series process *** improves the basic self-attention model in both width and *** the multihead structure,the HMSAN can pay attention to different aspects of the complicated chemical process and obtain the global dynamic ***,the multiple heads in parallel lead to redundant information,which cannot improve the diagnosis *** the hierarchical structure,the redundant information is reduced and the deep local time-related features are further ***,a novel many-to-one training strategy is introduced for HMSAN to simplify the training procedure and capture the long-term ***,the effectiveness of the proposed method is demonstrated by two chemical *** experimental results show that the proposed method achieves a great performance on time-series industrial data and outperforms the state-of-the-art approaches.

关键词： Self-attention mechanism Deep learning Chemical process Time-series Fault diagnosis

Toeplitz Operators and Carleson Measures for Weighted Bergman Spaces Induced by Regular Weights

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Acta Mathematica Sinica,English Series 2024年第5期40卷 1345-1359页

作者： Jun tao DU song Xiao Hasi WULAN Department of Mathematics Guangdong University of Petrochemical TechnologyMaoming 525000P.R.China Department of Mathematics Shantou UniversityShantou 515063P.R.China

In this paper,we give a universal description of the boundedness and compactness of Toeplitz operator T_(μ)^(ω)between Bergman spaces A_(η)^(p)and A_(υ)^(q)whenμis a positive Borel measure,1 详细信息

In this paper,we give a universal description of the boundedness and compactness of Toeplitz operator T_(μ)^(ω)between Bergman spaces A_(η)^(p)and A_(υ)^(q)whenμis a positive Borel measure,1

关键词： Bergman space Carleson measure Toeplitz operator regular weight

Spatial patterns of zooplankton abundance,biovolume,and size structure in response to environmental variables:a case study in the Yellow Sea and East China Sea

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Journal of Oceanology and Limnology 2024年第1期42卷 113-127页

作者： song SUN Haochen xian Xiaoxia SUN Mingliang ZHU Mengtan LIU Key Laboratory of Marine Ecology and Environmental Sciences Institute of OceanologyChinese Academy of SciencesQingdao 266071China Jiaozhou Bay National Marine Ecosystem Research Station Institute of OceanologyChinese Academy of SciencesQingdao 266071China University of Chinese Academy of Sciences Beijing 100049China Laboratory for Marine Ecology and Environmental Science Laoshan LaboratoryQingdao 266237China

The Yellow Sea(YS)and East China Sea(ECS)are highly dynamic marginal seas of the northwestern Pacific *** gain an in-depth understanding of zooplankton community structure,zooplankton abundance,biovolume,and size structure in summer 2017 in the YS and ECS were assessed using ZooScan imaging *** abundance and biovolume ranged 2.94–1187.14 inds./m^(3)and 3.13–3438.51 mm^(3)/m^(3),*** on the biovolume data of the categorized size classes of 26 identified taxonomic groups,the zooplankton community was classified into five groups,and each group was coupled with distinctive oceanographic *** the influence of the Yellow Sea Cold Water Mass,the Yellow Sea offshore group featured the lowest bottom temperature(10.84±3.42℃)and the most abundant Calanoids(mainly in the 2–3 mm size class).In the Yellow Sea inshore group,Hydrozoans showed the largest biovolume and dominated in the 3–4-mm and>5-mm size *** East China Sea offshore group,which was affected by the Kuroshio Branch Current,featured high temperature and salinity,and the lowest bottom dissolved oxygen(2.58±0.5 mg/L).The lowest values of zooplankton abundance and biovolume in the East China Sea offshore group might be attributed to the bottom dissolved oxygen *** East China Sea inshore group,which was mainly influenced by the Zhejiang-Fujian Coastal Current and Changjiang Diluted Water,was characterized by high chlorophyll a and the largest biovolume of carnivorous Siphonophores(280.82±303.37 mm^(3)/m^(3)).The Changjiang River estuary offshore group showed the most abundant Cyclopoids,which might be associated with the less turbid water mass in this *** temperature was considered the most important factor in shaping the size compositions of Calanoids in different groups.

关键词： zooplankton size structure ZooScan Yellow Sea East China Sea

Review of the research on the development and utilization of clay-type lithium resources

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Particuology 2024年第4期87卷 46-53页

作者： Ruiqi Xie Zhihui Zhao Xiong Tong xian Xie Qiang song Peiqiang Fan Faculty of Land Resource Engineering Kunming University of Science and TechnologyKunming650093China Yunnan Engineering Research Center for Metal Tailings Resource Utilization Kunming650093China

Since the demands for lithium have been in explosive growth recently and several great clay lithium resources were founded in China,the development and utilization of clay-type lithium resources become a hot *** order to provide a guidance for the concentration and extracting lithium of clay-type lithium resources,this review systematically summarized the main types and characteristics of clay-type lithium resources and the research status of lithium extraction from clay lithium ***,the flotation research status of the main mineral of clay lithium ore was also ***,we discussed the difficulties in the development and utilization of clay-type lithium ore and put forward the subsequent research *** paper can provide a guidance for the con-centration and extracting lithium of clay-type lithium resources in the future.

关键词： Clay lithium Clay mineral flotation Lithium extraction Leaching

Gender based differences in patients with acute coronary syndrome:findings from Chinese Registry of Acute Coronary Events (CRACE)

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Chinese Medical Journal 2007年第12期120卷 1063-1067页

作者： song xian-tao CHEN Yun-dai PAN Wei-qi LU Shu-zheng Department of Cardiology Beijing Anzhen Hospital Capital Medical University Beijing 100029 China

Background Many studies have examined gender related differences in the presenting symptoms, management and prognosis of patients with acute coronary syndrome （ACS）. Much data are available from industrialized countries, in which ACS is a major cause of morbidity and mortality, but relatively little information has been obtained from China, where an epidemic of cardiovascular disease is starting to emerge. The purpose of this study was to assess the differences in clinical practice in a national Chinese sample. Methods A total of 12 medical teaching hospitals participated in CRACE. Data collection began in 2001 and continued until 2004, 1301 patients with ACS were enrolled into the study. We compared the clinical demographics, different therapies and outcomes in hospitals between female and male patients with ACS. Results Patients had an average age of 63.13 years （ranging from 27 to 93 years） and 318 female and 983 male subjects were enrolled. Female subjects were older than male patients （67.23 years vs 61.80 years, P〈0.0001）. The incidence of angina, heart failure, diabetes mellitus and hypertension in the female group was higher than in male group （73.6% vs 62.3%, P〈0.0001; 8.2% vs 5.7%, P=-0.031; 30.8% vs 18.6%, P〈0.0001 and 66.4% vs 56.8%, P=-0.001 respectively）, but the incidence of smoking was less in the female group than in the male group （6.6% vs 66.2%, P〈0.0001）. More male patients presented with ST-segment elevation myocardial infarction （STEMI） compared with female patients （48.5% vs 39%, P=0.002）. With the exception of β-blocker administration, no differences were found among medications including aspirin, ACEI, lipid lowering agents and low-molecular-weight heparin （LMWH） between female and male patients presenting with ACS in hospitals. Compared with male patients with non-ST-segment elevation （NSTE） ACS, female subjects were more prone to receive β-blockers （75.1% vs 63.4%, P=0.001）. Among STEMI and NSTE-ACS patients, fewer female subjects rece

关键词： gender acute coronary syndrome Chinese

Boundary Regularity of Isometries Between Infinitely Flat Complex Domains

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Acta Mathematica Sinica,English Series 2024年第6期40卷 1375-1387页

作者： Jin song LIU Fei tao Hong Yu WANG Academy of Mathematics and Systems Science Chinese Academy of SciencesBeijing 100190P.R.China School of Mathematical Sciences University of Chinese Academy of SciencesBeijing 100049P.R.China Beijing International Center for Mathematical Research Peking UniversityBeijing 100871P.R.China School of Science Beijing University of Posts and TelecommunicationsBeijing 100876P.R.China Key Laboratory of Mathematics and Information Networks(Beijing University of Posts and Telecommunications) Ministry of EducationBeijing 100876P.R.China

In this paper we prove that isometries with respect to the Kobayashi metric between certain domains having boundary points at which the boundary is infinitely flat extend continuously to the *** strategy is to reestab... 详细信息

关键词： Boundary extension Kobayashi metric isometries