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Application of ARIMA-RTS optimal smoothing algorithm in gas well production prediction

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Petroleum 2022年第2期8卷 270-277页

作者： Yonggang Duan Huan Wang Mingqiang Wei linjiang tan Tao Yue School of Petroleum and Natural Gas Engineering Southwest Petroleum UniversityChengdu610500China School of Mechanical and Electrical Engineering Southwest Petroleum UniversityChengdu610500China

Gas field production forecast is an important basis for decision-making in the gas industry.How to accurately predict the dynamic production during gas field development is an important content of reservoir engineering research.Reservoir numerical simulation is the most common method for predicting oil and gas production.However,it requires a lot of data to build an accurate geological model which is tedious and time-consuming.At present,many scholars have used machine learning and data mining methods to predict oil and gas production,but they have not considered whether the use of increasing production measures will affect the predicted results.Thus,ARIMA-RTS optimal smooth algorithm is the first applied to establish the prediction model of gas well production.According to the historical production data,the model is processed,the production differential autoregressive integral moving average(ARIMA)model in time series is established,then ARIMA model is combined with RTS(Rauch Tung Striebel)smoothing,and the production prediction model is constructed.RTS smoothing algorithm is an enhanced version of Kalman filter.The measurements are firstly processed by the forward filter,and then,a separate backward smoothing pass is used for obtaining the smoothing solution.The correctness of ARIMA-RTS model was verified with the actual production data.The results show that the prediction based on ARIMA-RTS model can accurately reflect the production performance of gas well.This method can effectively reduce the error caused by stimulation when predicting.When using the ARIMA-RTS model and the ARIMA-Kalman model to predict the production of the same gas well,the prediction accuracy of ARIMA-RTS model is higher than that of ARIMA-Kalman model in production wells with stimulation.Compared with that of the ARIMA-Kalman model,the mean relative error fitted by the ARIMA-RTS model is reduced by 46.3%,and the relative mean square error is reduced by 56.48%.ARIMA-RTS optimal smooth algorithm improves the prediction accuracy of gas wel

关键词： Production forecasting ARIMA RTS Kalman filter

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Genes & Diseases 2024年第1期11卷 367-381页

作者： Yunchao Zhang Jiayu tang Cheng Wang Qinxiu Zhang Anqi Zeng linjiang Song School of Medical and Life Sciences Chengdu University of Traditional Chinese MedicineChengduSichuan 611137China Institute of Translational Pharmacology and Clinical Application Sichuan Academy of Chinese Medical ScienceChengduSichuan 610041China School of Pharmacy Chengdu University of Traditional Chinese MedicineChengduSichuan 611137China

The incidence and mortality rates of cancer are increasing every year worldwide but the survival rate of cancer patients is still unsatisfactory.Therefore,it is necessary to further elucidate the molecular mechanisms involved in tumor development and drug resis-tance to improve cancer cure or survival rates.In recent years,autophagy has become a hot topic in the field of oncology research,which plays a double-edged role in tumorigenesis,pro-gression,and drug resistance.Meanwhile,long non-coding RNA(lncRNA)has also been shown to regulate autophagy,and the two-sided nature of autophagy determines the dual regulatory role of autophagy-related IncRNAs(ARlncRNAs).Therefore,ARlncRNAs can be effective ther-apeutic targets for various cancers.Furthermore,the high abundance and stability of ARlncR-NAs in tumor tissues make them promising biomarkers.In this review,we summarized the roles and mechanisms of ARlncRNAs in tumor cell proliferation,apoptosis,migration,invasion,drug resistance,angiogenesis,radiation resistance,and immune regulation.In addition,we described the clinical significance of these ARlncRNAs,including as biomarkers/therapeutic targets and their association with clinical drugs.

关键词： Apoptosis Autophagy Biomarker Cancer Drug resistance LncRNA

Influence of ambient temperature on the CO_(2)emitted of light-duty vehicle

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Journal of Environmental Sciences 2024年第6期140卷 59-68页

作者： Dan tan Yachao Wang Jianwei tan Jiachen Li Changyu Wang Yunshan Ge School of Mechanical Engineering Beijing Institute of TechnologyBeijing 100081China

Because of global warming,people have paid more attention to greenhouse gas emitted by vehicles.To quantify the impact of temperature on vehicle CO_(2)emissions,this study was conducted using the world light vehicle test cycle on two light-duty E10 gasoline vehicles a ambient temperatures of-10,0,23,and 40℃,and found that CO_(2)emission factors of Vehicle1 in the low-speed phase were 22.07%and 20.22%higher than those of Vehicle 2 at cold star and hot start under-10℃.The reason was vehicle 1 had a larger displacement and more friction pairs than vehicle 2.There was the highest CO_(2)emission at the low-speed phase due to low average speed,frequent acceleration,and deceleration.The CO_(2)temperature factor and the ambient temperature had a strong linear correlation(R2=0.99).According to CO_(2)temperature factors and their relationships,CO_(2)emission factors of other ambien temperatures could be calculated when the CO_(2)emission factor of 23℃was obtained,and the method also could be used to obtain the CO_(2)temperature factors of different vehicles.To separate the effect of load setting and temperature variation on CO_(2)emission quantitatively a method was proposed.And results showed that the load setting was dominant for the CO_(2)emission variation.Compared with 23℃,the CO_(2)emission for vehicle 1 caused by load setting variation were 62.83 and 47.42 g/km,respectively at-10 and 0℃,while those fo vehicle 2 were 45.01 and 35.63 g/km,respectively.

关键词： CO_(2)emission Ambient temperature E10 gasoline Light-duty vehicle WLTC

Amorphous hybrid tungsten oxide–nickel hydroxide nanosheets used as a highly efficient electrocatalyst for hydrogen evolution reaction

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Nano Research 2024年第4期17卷 2499-2508页

作者： Chao Lyu Chenghai Dai Yiwei tan State Key Laboratory of Materials-Oriented Chemical Engineering School of Chemistry and Chemical EngineeringNanjing Tech UniversityNanjing 211816China

There are more challenges for alkaline hydrogen evolution reaction(HER)via simultaneously expediting the electron-coupled water dissociation process(Volmer step)and the following electrochemical H_(2) desorption(Heyrovsky step).Hybrid amorphous electrocatalysts are highly desirable for efficient hydrogen evolution from water-alkali electrolyzers due to the bifunctionality for the different elementary steps of HER and optimal interactions with water molecules and the reactive hydrogen intermediates(Had).Herein,the synthesis of amorphous hybrid ultrathin(tungsten oxide/nickel hydroxide)hydrate(a-[WO_(3)/Ni(OH)_(2)]·0.2H_(2)O)nanosheets on nickel foam(NF)for efficient alkaline HER is described.The structural and composition features of a-[WO_(3)/Ni(OH)_(2)]·0.2H_(2)O are characterized in detailed.The resulting a-[WO_(3)/Ni(OH)_(2)]·0.2H_(2)O/NF electrocatalyst with the synergistic effect of both hybrid components for the HER elementary steps shows greatly improved the activity and durability for the HER with a low overpotential of-41 and-163 mV at-10 and-500 mA·cm^(-2),respectively,a Tafel slope as low as-72.9 mV·dec^(-1),and long-term stability of continuous electrolysis for at least 150 h accompanying by inappreciable overpotential change in 1 M KOH.In the hybrid a-[WO_(3)/Ni(OH)_(2)]·0.2H_(2)O,Ni(OH)_(2) and WO_(3) moieties are separately responsible for accelerating dissociative adsorption of water and weakening Had adsorption strength,which is beneficial to the improvement of the alkaline HER activity.

关键词： amorphous nanomaterial bimetallic electrocatalyst tungsten oxide ultrathin nanosheet hydrogen evolution reaction

A Novel Extremum Seeking Control to Enhance Convergence and Robustness in the Presence of Nonlinear Dynamic Sensors

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Journal of Systems Science & Complexity 2024年第1期37卷 3-21页

作者： LIU Hengchang tan Ying OETOMO Denny School of Electrical Mechanical and Infrastructure EngineeringThe University of MelbourneParkville VIC 3010Australia

This paper focuses on optimizing an unknown cost function through extremum seeking(ES)control in the presence of a slow nonlinear dynamic sensor responsible for measuring the cost.In contrast to traditional perturbation-based ES control,which often suffers from sluggish convergence,the proposed method eliminates the time-scale separation between sensor dynamics and ES control by using the relative degree of the nonlinear sensor system.To improve the convergence rate,the authors incorporate high-frequency dither signals and a differentiator.To enhance the robustness with the existence of rapid disturbances,an off-the-shelf linear high-gain differentiator is applied.The first result demonstrates that,for any desired convergence rate,with properly tuned parameters for the proposed ES algorithm,the input of the cost function can converge to an arbitrarily small neighborhood of the optimal solution,starting from any initial condition within any given compact set.Furthermore,the second result shows the robustness of the proposed ES control in the presence of sufficiently fast,zero-mean periodic disturbances.Simulation results substantiate these theoretical findings.

关键词： Averaging extremum seeking optimization singular perturbation time-scale separation

An Improved Method for Approximating the Infinite-Horizon Value Function of the Discrete-Time Switched LQR Problem

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Journal of Systems Science & Complexity 2024年第1期37卷 22-39页

作者： HOU tan LI Yuanlong LIN Zongli Department of Automation Shanghai Jiao Tong UniversityShanghai 200240China Key Laboratory of System Control and Information Processing Ministry of Education of ChinaShanghai 200240China Shanghai Engineering Research Center of Intelligent Control and Management Shanghai 200240China Charles L.Brown Department of Electrical and Computer Engineering University of VirginiaCharlottesvilleVA 22904-4743USA

This paper considers the problem of approximating the infinite-horizon value function of the discrete-time switched LQR problem.In particular,the authors propose a new value iteration method to generate a sequence of monotonically decreasing functions that converges exponentially to the value function.This method facilitates us to use coarse approximations resulting from faster but less accurate algorithms for further value iteration,and thus,the proposed approach is capable of achieving a better approximation for a given computation time compared with the existing methods.Three numerical examples are presented in this paper to illustrate the effectiveness of the proposed method.

关键词： Optimal control switched linear systems switched LQR problem.

The symmetric space,strong isotropy irreducibility and equigeodesic properties

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Science China Mathematics 2024年第1期67卷 129-148页

作者： Ming Xu Ju tan School of Mathematical Sciences Capital Normal UniversityBeijing 100048China School of Microelectronics and Data Science Anhui University of TechnologyMa'anshan 243032China

A smooth curve on a homogeneous manifold G/H is called a Riemannian equigeodesic if it is a homogeneous geodesic for any G-invariant Riemannian metric.The homogeneous manifold G/H is called Riemannian equigeodesic,if for any x∈G/H and any nonzero y∈Tx(G/H),there exists a Riemannian equigeodesic c(t) with c(0)=x and ■(0)=y.These two notions can be naturally transferred to the Finsler setting,which provides the definitions for Finsler equigeodesics and Finsler equigeodesic spaces.We prove two classification theorems for Riemannian equigeodesic spaces and Finsler equigeodesic spaces,respectively.Firstly,a homogeneous manifold G/H with a connected simply connected quasi compact G and a connected H is Riemannian equigeodesic if and only if it can be decomposed as a product of Euclidean factors and compact strongly isotropy irreducible factors.Secondly,a homogeneous manifold G/H with a compact semisimple G is Finsler equigeodesic if and only if it can be locally decomposed as a product,in which each factor is Spin(7)/G2,G2/SU (3) or a symmetric space of compact type.These results imply that the symmetric space and the strongly isotropy irreducible space of compact type can be interpreted by equigeodesic properties.As an application,we classify the homogeneous manifold G/H with a compact semisimple G such that all the G-invariant Finsler metrics on G/H are Berwald.It suggests a new project in homogeneous Finsler geometry,i.e.,to systematically study the homogeneous manifold G/H on which all the G-invariant Finsler metrics satisfy a certain geometric property.

关键词： equigeodesic equigeodesic space flag manifold orbit type stratification symmetric space strongly isotropy irreducible space

Synchronization of Drive-Response Networks With Delays on Time Scales

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IEEE/CAA Journal of Automatica Sinica 2024年第4期11卷 1063-1065页

作者： Yanxia tan Zhenkun Huang the School of Science Jimei UniversityXiamen 361021China

Dear Editor,This letter deals with the synchronization in drive-response networks with discrete and distributed delays on time scales.Based on the theory of calculus on time scales,Lyapunov functional method and inequality technique,we obtain new sufficient conditions to ensure synchronization criteria which are dependent on boundedness of grainness but independent of the types of delays.Numerical simulations are given to illustrate the effectiveness of our new results.

关键词： inequality letter boundedness

Options and survival benefits of conversion therapy for unresectable hepatocellular carcinoma

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World Journal of Gastroenterology 2024年第18期30卷 2479-2481页

作者： Wong Hoi She tan To Cheung Department of Surgery The University of Hong KongHong Kong 999077China

In the study by Wu et al,patients with unresectable hepatocellular carcinoma were subjected to transarterial chemoembolization(TACE)as a conversion therapy in order to render their tumors suitable for resection.A nomogram was devised and shown to be effective in predicting the survival of these patients.Generalization of the results,however,is questionable since the study subjects consisted of patients who had resection after TACE while excluding patients with the same disease but not suitable for TACE.Immunotherapy can be considered to be an option for conversion therapy.However,markers for determining responses to a conversion therapy and for guiding the decision between TACE and sequential immunotherapy have been lacking.The question of whether effective conversion therapy can truly enhance overall survival remains unanswered.

关键词： Conversion therapy Immunotherapy Liver resection Survival Transarterial chemoembolization Unresectable hepatocellular carcinoma