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Operation optimization of plugged screen cleanup by rotary water jetting

Petroleum Science 2014年第1期11卷 122-130页

作者： Dong Changyin Li Yanlong Long Jiajia Zhang Qinghua wang dengqing Wu Jianping College of Petroleum Engineering China University of Petroleum Qingdao Research Institute of Production Technology Shengli Oilfield SINOPEC

The rotary water jetting is one of the most important techniques for horizontal well *** jet flow is used to remove plugging particles from sand control screens to recover their ***,the operation optimization of this technique depends mainly on experience due to absence of applicable evaluation and design models for removing plugging *** paper presents an experimental setup to simulate the cleanup process of plugged screens by rotary water jetting on the surface and to evaluate the performance of a jetting *** real plugged screens pulled from damaged wells,a series of tests were performed,and the qualitative relationships between the cleanup efficiency and various operational parameters,such as the type of fluids used,flow rate,mode of tool movement,etc.,were *** test results indicated that the cleanup performance was much better when the rotary jetting tool moved and stopped periodically for a certain time than that when it reciprocated at a constant *** be exact,it was desirable for the rotary jetting tool to move for 1.5-2 m and stop for 2-4 min,which was called the ＂move-stop-move＂ *** cleanup performance could be obtained at high flow rates,and the flow rate was recommended to be no lower than 550-600 L/*** test results also indicated that complex mud acid was better than clean water in terms of cleanup *** cleanup efficiency and high screen permeability recovery could be achieved for severely plugged *** jetting is preferred for the cleanup of horizontal wells with severely plugged screens,and the screen permeability recovery ratio may reach 20％ if optimized operation parameters were used.

关键词： Sand control screen cleanup performance rotary jetting operation optimization experimental simulation

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A novel order reduction method for nonlinear dynamical system under external periodic excitations

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Science China(Technological Sciences) 2010年第3期53卷 684-691页

作者： CAO dengqing,wang JinLin & HUANG WenHu School of Astronautics,Harbin Institute of Technology,PO Box 137,Harbin 150001,China School of Astronautics Harbin Institute of Technology

The concept of approximate inertial manifold (AIM) is extended to develop a kind of nonlinear order reduction technique for non-autonomous nonlinear systems in second-order form in this *** the modal transformation,a large nonlinear dynamical system is split into a 'master' subsystem,a 'slave' subsystem,and a 'negligible' ***,a novel order reduction method (Method I) is developed to construct a low order subsystem by neglecting the 'negligible' subsystem and slaving the 'slave' subsystem into the 'master' subsystem using the extended *** a comparison,Method II accounting for the effects of both 'slave' subsystem and the 'negligible' subsystem is also applied to obtain the reduced order ***,a typical 5-degree-of-freedom nonlinear dynamical system is given to compare the accuracy and efficiency of the traditional Galerkin truncation (ignoring the contributions of the slave and negligible subsystems),Method I and Method *** is shown that Method I gives a considerable increase in accuracy for little computational cost in comparison with the standard Galerkin method,and produces almost the same accuracy as Method ***,a 3-degree-of-freedom nonlinear dynamical system is analyzed by using the analytic method for showing predominance and convenience of Method I to obtain the analytically reduced order system.

关键词： Galerkin method nonlinear systems dimension reduction post-processed method model truncation

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福建省林产品物流节点质量评价

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林业经济问题 2019年第6期39卷 659-664页

作者：王登清福建船政交通职业学院管理工程系福州大学经济与管理学院

应用关联系数标准差方法改进引力模型,选取5个维度的指标,对福建省林产品物流节点的质量进行评价,结果表明:福建省林产品物流节点、林产品产量、物流从业人员的影响权重较大,林产品物流节点结构呈现“东强西弱,南高北低”的特点,福州、... 详细信息

应用关联系数标准差方法改进引力模型,选取5个维度的指标,对福建省林产品物流节点的质量进行评价,结果表明:福建省林产品物流节点、林产品产量、物流从业人员的影响权重较大,林产品物流节点结构呈现“东强西弱,南高北低”的特点,福州、泉州、三明是福建省林产品物流辐射全省的3个轴心节点。针对福建省林产品物流节点质量的特点,应该加强林产品核心枢纽建设、建立东西物流通道等,以便提升福建省林产品物流节点质量。

关键词：林产品物流轴心节点节点结构节点质量

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新零售模式下单中心物流配送路径优化研究

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福州大学学报（自然科学版） 2019年第5期47卷 695-699页

作者：王登清福州大学经济与管理学院福建船政交通职业学院管理工程系

针对新零售模式下单中心物流配送路径规划问题,综合考虑运输成本、道路拥堵程度和配送业务的时效性建立优化模型,并通过改进遗传算法求解.算例结果表明,改进遗传算法实现的模型效率更高、求解质量更佳.

关键词：新零售物流配送遗传算法车辆路径优化时间窗

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The reformation of catalyst:From a trial-and-error synthesis to rational design

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Nano Research 2024年第4期17卷 3261-3301页

作者： Ligang wang Jiabin Wu Shunwu wang Huan Liu Yao wang Dingsheng wang Department of Chemistry Tsinghua UniversityBeijing 100084China

The appropriate catalysts can accelerate the reaction rate and effectively boost the efficient conversion of various molecules,which is of great importance in the study of chemistry,chemical industry,energy,materials and environmental ***,efficient,environmentally friendly,and easy to operate synthesis methods have been used to prepare various types of *** previous studies have reported the synthesis and characterization of the aforementioned catalysts,more still remain in trial and error methods,without in-depth consideration and improvement of traditional synthesis ***,we comprehensively summarize and compare the preparation methods of the trial-and-error synthesis strategy,structure–activity relationships and density functional theory(DFT)guided catalysts rational design for nanomaterials and atomically dispersed *** also discuss in detail the utilization of the nanomaterials and single atom catalysts for converting small molecules(H_(2)O,O_(2),CO_(2),N_(2),etc.)into value-added products driven by electrocatalysis,photocatalysis,and ***,the challenges and outlooks of mass preparation and production of efficient and green catalysts through conventional trial and error synthesis and DFT theory are featured in accordance with its current development.

关键词： trial-and-error synthesis structure–activity relationships density functional theory(DFT)guidance nanomaterials atomically dispersed catalysts

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Numerical Analysis of PRISM-PY Calculations for Hard-and Soft-Core Generic Polymer Models

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Chinese Journal of Polymer Science 2024年第4期42卷 532-543页

作者： Qiang wang Department of Chemical and Biological Engineering Colorado State University1370 Campus DeliveryFort CollinsCO80523-1370USA

Generic polymer models capturing the chain connectivity and excluded-volume interactions between polymer segments can be classified, according to whether or not the 3D integral of the latter diverges, into hard- and soft-core models. Taking homogeneous systems of compressible homopolymer melts (or equivalently homopolymer solutions in an implicit, good solvent) in the continuum as an example, we recently compared the correlation effects on the structural and thermodynamic properties of the hard- and soft-core models given by the polymer reference interaction site model (PRISM) theory with the Percus-Yevick (PY) closure (Polymers 2023, 15, 1180). Here we analyzed in detail the numerical errors and behavior of the interchain pair correlation functions (PCFs) given by the PRISM-PY calculations of these models using an efficient numerical approach that we proposed. Our numerical approach has the least number of independent variables to be iteratively solved, analytically treats the discontinuities caused by the non-bonded pair potential (such as that of the hard spheres) and takes only the inverse Fourier transform of the interchain indirect PCF between polymer segments (which is continuous and decays towards 0 with increasing wavenumber much faster than both the interchain direct and total PCFs), and is essential for us to accurately solve the PRISM-PY theory for chain length N as large as 106. To capture the correlation-hole effect, the real-space cut-off in the PRISM calculations should be proportional to the square root of N.

关键词： Generic polymer models Soft potentials Polymer reference interaction site model theory

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Linear-Quadratic Pareto Cooperative Game for Mean-Field Backward Stochastic System

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Journal of Systems Science & Complexity 2024年第3期37卷 947-964页

作者： wang Yu School of Control Science and Engineering Shandong UniversityJinan 250061China

This paper focuses on a Pareto cooperative differential game with a linear mean-field backward stochastic system and a quadratic form cost functional. Based on a weighted sum optimality method, the Pareto game is equivalently converted to an optimal control problem. In the first place,the feedback form of Pareto optimal strategy is derived by virtue of decoupling technology, which is represented by four Riccati equations, a mean-field forward stochastic differential equation(MF-FSDE),and a mean-field backward stochastic differential equation(MF-BSDE). In addition, the corresponding Pareto optimal solution is further obtained. Finally, the author solves a problem in mathematical finance to illustrate the application of the theoretical results.

关键词： Backward stochastic differential equation linear-quadratic control mean-field Pareto optimality

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Light People: Professor Fanglin Bao and his cover story

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Light(Science & Applications) 2024年第6期13卷 1015-1020页

作者： Ji wang School of Science Westlake UniversityHangzhouZhejiangPR China

Qu Yuan,a renowned ancient Chinese poet,once pondered in his work Heavenly Inquiry:“If the sun’s light is absent,from where does the radiance of the Hero Flower emanate?”The ability to see clearly in the darkest of nights has long been a sought-after magical power by *** holds not only immense technological significance for computer vision and remote sensing but also profound implications for transcending the dichotomy between day and night in our daily *** Fanglin Bao from Westlake University has made significant breakthroughs in this field,bringing us closer to a world where we can transform night into *** groundbreaking research on Heat-Assisted Detection and Ranging(HADAR)and night vision was featured as the cover story in Nature on July 26,2023.

关键词： bringing breakthrough holds

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A multi-source information fusion layer counting method for penetration fuze based on TCN-LSTM

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Defence Technology（防务技术） 2024年第3期33卷 463-474页

作者： Yili wang Changsheng Li Xiaofeng wang Nanjing University of Science and Technology Nanjing 210094JiangsuChina State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing 100081China

When employing penetration ammunition to strike multi-story buildings,the detection methods using acceleration sensors suffer from signal aliasing,while magnetic detection methods are susceptible to interference from ferromagnetic materials,thereby posing challenges in accurately determining the number of *** address this issue,this research proposes a layer counting method for penetration fuze that incorporates multi-source information fusion,utilizing both the temporal convolutional network(TCN)and the long short-term memory(LSTM)recurrent *** leveraging the strengths of these two network structures,the method extracts temporal and high-dimensional features from the multi-source physical field during the penetration process,establishing a relationship between the multi-source physical field and the distance between the fuze and the target plate.A simulation model is developed to simulate the overload and magnetic field of a projectile penetrating multiple layers of target plates,capturing the multi-source physical field signals and their patterns during the penetration *** analysis reveals that the proposed multi-source fusion layer counting method reduces errors by 60% and 50% compared to single overload layer counting and single magnetic anomaly signal layer counting,*** model's predictive performance is evaluated under various operating conditions,including different ratios of added noise to random sample positions,penetration speeds,and spacing between target *** maximum errors in fuze penetration time predicted by the three modes are 0.08 ms,0.12 ms,and 0.16 ms,respectively,confirming the robustness of the proposed ***,the model's predictions indicate that the fitting degree for large interlayer spacings is superior to that for small interlayer spacings due to the influence of stress waves.

关键词： Penetration fuze Temporal convolutional network(TCN) Long short-term memory(LSTM) Layer counting Multi-source fusion

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Assessment of tree-ring mercury radial translocation and age effect in Masson pine:Implications for historical atmospheric mercury reconstruction

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Journal of Environmental Sciences 2024年第4期138卷 266-276页

作者： Xu Liu Xun wang Dingyong wang College of Resources and Environment Southwest UniversityChongqing 400715China State Key Laboratory of Environmental Geochemistry Institute of GeochemistryChinese Academy of SciencesGuiyang 550081China

The tree ring has been regarded as an emerging archive to reconstruct historical atmospheric mercury(Hg)trends,but with the large knowledge gaps in the *** this study,we comprehensively evaluated the Hg source,radial translocation and age effect of Masson pine(Pinus massoniana)tree ring at *** in Chongqing,to assess the suitability of such tree ring as the archive of atmospheric *** showed that distinct variabilities among Masson pine tree-ring Hg concentration *** Hg concentration significantly increased along with stem height(P<0.05),indicating the Hg in tree rings mainly derived from foliage uptake atmospheric *** found a distinct age effect that the tree ring of young trees had the higher Hg ***,we used the advection-diffusion model to demonstrate how Hg concentration shifted by the advection or/and diffusion in tree *** modeling results showed that the advection induced radial translocation during the young growth period of tree was a plausible mechanism to result in the tree-ring Hg record largely different from the trend of anthropogenic Hg emissions in *** finally suggest that in further Hg dendrochemistry,better discarding the tree-ring Hg profile of the young growth period to reduce impacts of the radial translocation and age effect.

关键词： Masson pine Tree-ring mercury Radial translocation Tree age effect

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