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COORELATION ANALySIS OF SURFACE PRESSURE FLUCTUATIONS ON THREE EQUISPACED CyLINDERS

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Journal of Hydrodynamics 2001年第2期13卷 55-62页

作者： dong, L.y. Xu, y.H. Huang, D.Q. Inst. of Appl. Math. and Mech. Shanghai Univ. Shanghai 200072 China

The fluctuating pressures on the surface of three circular cylinders in equispaced arrangement were measured simultaneously in the medium subcritical regime (Re=3×104). The distributions of their rms values and circumferential correlation were obtained in the spacing range from 1.25 to 6.0. The spatial correlation of pressures of two pressure taps on two different cylinders at the same azimuth was investigated as well. Owing to different flow patterns in various arrangements and spacing, these correlation curves of pressure show different distributions. The lift fluctuation can be estimated qualitatively from the circumferential coefficient curve with the knowledge of the rms pressure distribution. Some critical spacing for each arrangement were found that the flow regimes and the corresponding pressure correlation take a sudden change. Flow interference between cylinders in each arrangement was also discussed with various flow regimes.

关键词： Cylinders (shapes) Experiments Flow interactions Flow patterns Pressure distribution Pressure measurement

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从领域到属性:亲环境行为测量的问题及建议

心理科学进展 2025年第1期33卷 163-175页

作者：张玥董艺佳蒋奖华北电力大学经济与管理学院北京102206 香港城市大学社会与行为科学系香港北京师范大学心理学部应用实验心理北京市重点实验室心理学国家级实验教学示范中心(北京师范大学)北京100875

已有研究开发了大量的亲环境行为测量工具,涉及量表、个体行为范式和群体博弈范式,其中大多数测量工具是基于行为领域设计,节约、出行、垃圾处理、消费和公域行为是5个最常被提及的领域。现有依据行为领域的亲环境行为测量方式存在标准... 详细信息

已有研究开发了大量的亲环境行为测量工具,涉及量表、个体行为范式和群体博弈范式,其中大多数测量工具是基于行为领域设计,节约、出行、垃圾处理、消费和公域行为是5个最常被提及的领域。现有依据行为领域的亲环境行为测量方式存在标准化程度低及测量结果推广性受限的问题,这主要是由于缺少对行为属性这一行为决定性特征的关注。未来研究应基于行为属性选用和开发标准化测量工具,并选取多种真实行为作为效标进行效度检验。

关键词：亲环境行为行为领域行为属性测量

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MESHFREE METHOD BASED ON POINT COLLOCATION FOR METAL FORMING SIMULATION

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Acta Metallurgica Sinica(English Letters) 2006年第2期19卷 79-84页

作者： H.y. Wen X.H. dong X.y. Ruan Department of Plasticity Forming Engineering Shanghai Jiaotong University Shanghai 200030 China

A meshfree method based on reproducing kernel approximation and point collocation is presented for analysis of metal ring compression. The point collocation method is a true meshfree method without the employment of a background mesh. It is shown that, in a point collocation approach, the remesh problem because of the mesh distortion in FEM （finite element method） and the low efficiency in Galerkin-based meshfree method are avoided. The corrected kernel functions are introduced to the stabilization of free-surface boundary conditions. The solution of symmetric ring compression problem is compared with a conventional finite element solution, and reasonable results have been obtained.

关键词： meshfree method RKPM (reproducing kernel particle method) point collocation metal forming frictional contact

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社区团购背景下考虑库存可得性的需求估计

管理工程学报 2025年第1期39卷 170-181页

作者：谭宇阳郭春香蔡东四川大学商学院

社区团购背景下的顾客选择行为不仅受到销售可得性的影响,还受到库存可得性的影响,传统的顾客选择模型不适用于社区团购背景。针对该问题,本文结合经典的multinomial logit(MNL)模型,通过分析社区团购背景下的顾客选择行为,构建了考虑... 详细信息

社区团购背景下的顾客选择行为不仅受到销售可得性的影响,还受到库存可得性的影响,传统的顾客选择模型不适用于社区团购背景。针对该问题,本文结合经典的multinomial logit(MNL)模型,通过分析社区团购背景下的顾客选择行为,构建了考虑库存可得性的顾客选择模型。基于此,在部分数据可用情形下,本文构建了不完全数据的最大似然估计模型,并设计了两阶段算法,将原问题转化为不等长销售期的需求估计问题,以求解需求估计相关参数,还原顾客的真实需求。最后,通过对实际案例的结果分析,本文验证了模型和算法的有效性。研究表明,本文研究成果不仅对社区团购的销售计划制定具有一定指导意义,而且可进一步推广到生鲜电商运营管理领域。

关键词：收益管理需求估计库存可得性两阶段算法

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建设工程全过程造价管理策略研究

价值工程 2025年第1期44卷 15-18页

作者：伏冬冬淮浙电力有限责任公司凤台发电分公司淮南232131

本研究旨在探讨建设工程项目全过程造价管理策略,以提高项目的经济效益和管理效率。研究内容涵盖了项目的决策、设计、招投标、施工及竣工各阶段的造价管理目标与策略。通过设计阶段风险评估与成本控制、招投标策略、施工进度与成本动... 详细信息

本研究旨在探讨建设工程项目全过程造价管理策略,以提高项目的经济效益和管理效率。研究内容涵盖了项目的决策、设计、招投标、施工及竣工各阶段的造价管理目标与策略。通过设计阶段风险评估与成本控制、招投标策略、施工进度与成本动态控制及竣工结算审核与后评估等方法,构建了全面的造价管理体系。研究结果表明,现代化先进技术以及先进工具,可以有效降低项目成本风险,提高造价管理的精度和效率。通过建立完善的审核和反馈机制,可以及时发现并解决各阶段的问题,优化项目管理流程。本研究为建设工程项目的造价管理提供了科学的理论依据和实践指导,有助于推动行业的管理水平提升,实现绿色建筑和可持续发展的目标。

关键词：建筑工程工程全过程造价管理工程效益

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Facile synthesis of the dodecahydridododecaborate (B12H122-) from borane Lewis base adducts

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Science China Chemistry 2025年

作者： yi Jing Xin-Ran Liu Xing-Hua Wang Hui Han Sha-Sha Liang Xi-Meng Chen dong-Hui Wei Lai-Sheng Wang Xue-Nian Chen College of Chemistry Zhengzhou University School of Chemistry and Chemical Engineering Henan Key Laboratory of Boron Chemistry and Advanced MaterialsHenan Normal University Department of Chemistry Brown University

Polyhedral boranes are a class of well-known boron molecular clusters widely used in energy,chemistry,medicine,and materials science because of their unique physical and chemical *** efforts have been made in the past decades to find more effective synthetic methods for this important class of boron ***,existing synthetic methods suffer from low efficiency and low ***,we report a facile one-pot synthesis of[（CH3）3S]2B12H12with moderate yields at mild *** mechanisms for the multi-step chemoselective synthesis of B12H122-without other by-products are elucidated based on theoretical results and our previous *** Lewis base used in B–H bond condensation reaction,which acts as a hydrogen or to balance the newly generated polyhedral borane charges,is proposed and studied in *** current study has led to a more effective and selective synthetic method for B12H122-and has also implicated the syntheses of other new polyhedral boranes.

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Potassium ions and cyano group modified g-C3N4 for effective generation of H2O2 through two-electron oxygen reduction

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Science China Chemistry 2025年第1期 192-200页

作者： dongying Wang Shulan Pu yongmin Chen Ke Lei yujie Duan Linjiao Mao Xuhui Zeng Xi Luo yuntao Zhang yuqin dong Jin Zhong Zhang yan Sun School of Mechanical Engineering Chengdu University Department of Chemistry and Biochemistry University of California

Potassium ions （K+） doped graphitic carbon nitride （g-C3N4） was prepared by a thermal etching method using potassium hydroxide （KOH） as an ion *** transform infrared spectroscopy （FTIR） and X-ray photoelectron spectroscopy （XPS）results showed that the generation of the cyano group was detected while introducing K+.Under simulated sunlight irradiation,the sample with a K+doping amount of 10%showed the highest hydrogen peroxide （H2O2） generation rate of2,140.2μmol *** apparent quantum yield （AQy） at 400 nm and the solar-to-chemical conversion （SCC） are 4.35%and1.23%,respectively.K+acted as a bridge between g-C3N4layers,which enhanced charge transfer ***,the cyano group enhanced the adsorption capacity of protons （H+） and promoted the yield of *** catalyst exhibited excellent photocatalytic stability based on four-cycle *** addition,a mechanism study showed that superoxide radicals （·O2-）were the most important active species in the reaction *** production of H2O2was achieved through consecutive single-electron *** study deepens the understanding of the oxygen reduction reaction process and opens up a new venue for improving H2O2generation.

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An NIR-Ⅱ-emissive Ru(Ⅱ) metallacycle for efficient and safe immunotherapy

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Science China Chemistry 2025年第01期 5-7页

作者： Chonglu Li Jianbo Zhan Biao dong Institute of Health Inspection and Testing Hubei Provincial Center for Disease Control and Prevention State Key Laboratory on Integrated Optoelectronics College of Electronic Science and Engineering Jilin University

Immunotherapy, as a groundbreaking cancer treatment, has gained considerable attention for its utilization of the body’s immune system to combat tumors [1]. This therapy induces tumor cell apoptosis, triggering a sustained anti-tumor immune response and effectively preventing tumor recurrence and metastasis [2]. The fundamental principle lies in inducing tumor cell death through specific treatment modalities, leading to the release of a cascade of signaling molecules and antigens, thereby mobilizing the immune system to actively identify and attack tumor cells [3].

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Decentralized fault diagnosis of discrete-event systems with unreliable sensors using linear temporal logic

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Science China(Information Sciences) 2025年第1期 322-341页

作者： Weijie dong Shaoyuan LI Xiang yIN Key Laboratory of System Control and Information Processing Ministry of EducationDepartment of Automation Shanghai Jiao Tong University

In this paper,we investigate a decentralized diagnosis problem of a discrete-evnt system(DES) subject to unreliable sensors,where the sensor observations of local diagnosers may be non-deterministic as a result of possible *** studies on decentralized robust diagnosis can only deal with different types of sensor failures separately,e.g.,all sensors suffer from the same type of sensor failures such as intermittent sensor failures or permanent sensor ***,since sensors of different local diagnosers may face different external environments and have different internal characteristics,sensors corresponding to different local diagnosers may also have their own fault *** this paper,we propose a flexible framework of decentralized diagnosis for DES subject to unreliable sensors such that sensors of different local diagnosers are permitted to have different types of sensor *** this end,we extend the existing decentralized diagnosis framework to the case where there exist common sensors broadcasting their observations to all local *** apply linear temporal logic(LTL) to constrain infinite behaviors of private sensors of local diagnosers and common ***,a new notion of φ-codiagnosability is proposed as the necessary and sufficient condition for the existence of a decentralized diagnoser that works correctly under sensors,satisfying LTL-based sensor ***,we provide an effective approach to verify the φ-codiagnosability.

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