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An Upper Bound for the w-Weak Global Dimension of Pullbacks

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Algebra Colloquium 2021年第4期28卷 689-700页

作者： jin xie Gaohua Tang College of Mathematical Sciences Sichuan Normal University Chengdu 610068China College of Sciences Beibu Gulf UniversityQinzhouGuangxi 535011China

Let R be a commutative ring with identity and I0 an ideal of *** introduce and study the c-weak global dimension ***(R/I0)of the factor ring R/*** T be a w-linked extension of R,and we also introduce the wR-weak global dimension ***(T)of *** show that the ring T with ***(T)=0 is exactly a field and the ring T with ***(T)≤1 is exactly a *** an application,we give an upper bound for the w-weak global dimension of a Cartesian square(RDTF,M).More precisely,if T is w-linked over R,then ***(R)≤max{***(T)+w-fdR T,***(D)+w-fdn D}.Furthermore,for a Milnor square(RDTF,M),we obtain ***(R)≤max{***(T)+w-fdR T,***(D)+w-fdR D}.

关键词： c-operation c-flat module c-flat dimension wR-flat module WR-flat dimension

A Discrete Multi‑Objective Artificial Bee Colony Algorithm for a Real‑World Electronic Device Testing Machine Allocation Problem

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Chinese Journal of Mechanical Engineering 2022年第6期35卷 136-150页

作者： jin xie Xinyu Li Liang Gao State Key Laboratory of Digital Manufacturing Equipment and Technology Huazhong University of Science and TechnologyWuhan 430074China

With the continuous development of science and technology,electronic devices have begun to enter all aspects of human life,becoming increasingly closely related to human *** have higher quality requirements for electronic *** device testing has gradually become an irreplaceable engineering process in modern manufacturing enterprises to guarantee the quality of products while preventing inferior products from entering the *** the large output of electronic devices,improving the testing efficiency while reducing the testing cost has become an urgent problem to be *** study investigates the electronic device testing machine allocation problem(EDTMAP),aiming to improve the production of electronic devices and reduce the scheduling distance among testing machines through reasonable machine ***,a mathematical model was formulated for the EDTMAP to maximize both production and the scheduling distance among testing ***,we developed a discrete multi-objective artificial bee colony(DMOABC)algorithm to solve EDTMAP.A crossover operator and local search operator were designed to improve the exploration and exploitation of the algorithm,*** experiments were conducted to evaluate the performance of the proposed *** experimental results demonstrate the superiority of the proposed algorithm compared with the non-dominated sorting genetic algorithm II(NSGA-II)and strength Pareto evolutionary algorithm 2(SPEA2).Finally,the mathematical model and DMOABC algorithm were applied to a real-world factory that tests radio-frequency *** results verify that our method can significantly improve production and reduce the scheduling distance among testing machines.

关键词： Electronic device Machine allocation Multi-objective optimization Artificial bee colony algorithm

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Predictable site-selective radical fluorination of tertiary ethers

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Science China Chemistry 2020年第2期63卷 187-191页

作者： Junyang Ma Wentao Xu jin xie State Key Laboratory of Coordination Chemistry Jiangsu Key Laboratory of Advanced Organic MaterialsChemistry and Biomedicine Innovation CenterSchool of Chemistry and Chemical EngineeringNanjing University

In this communication,we disclose the first example of metal-free and site-selective radical fluorination of readily available tertiary alkyl ethers,enabled by synergistic photocatalysis and *** catalytic combination allows for exclusive fluorination of tertiary C–O bonds under mild conditions even in the presence of competing reaction *** excellent functional group tolerance affords valuable access to sterically hindered alkyl fluorides through late-stage modification of complex *** successful use of tertiary alkyl ethers in radical fluorination enhances the structural diversity of aliphatic fluorides that can be derived from naturally abundant alcohols.

关键词： cooperative catalysis C–O bond activation radical fluorination polarity-matching effect umpolung

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Investigation on the influence of vortex generator on particle resuspension

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Particuology 2024年第3期86卷 126-136页

作者： Dongchi Yu Jun-Li Lin jin-Han xie ASML 80W Tasman DrSan Jose95134CaliforniaUSA Department of Mechanics and Engineering Science at College of Engineering and State Key Laboratory for Turbulence and Complex Systems Peking UniversityBeijing100081China

The vortex generator(VG)and its well-known effect in flow optimization are widely studied and employed across different engineering ***,while the same working principles of VG may be well suited for the applications on surface-cleaning technologies,such promising potential is hardly,if any,explored in the published ***,in the present study,the influence on flow-induced particle resuspension brought by a rectangular vG in a channel flow is investigated with the help of highfidelity computational fluid dynamics *** increases of particle removal forces and resuspension rates are discovered in long,strip-like regions with reduced boundary-layer thickness resulted from the vG-induced vortices,and the enhancement effect is especially significant for configurations with the VG installed at a greater angle of *** is also shown that while the resuspension enhancements on the lower and the upper surfaces of the channel exhibit distinct statistical characteristics,having a VG in the channel improves the overall particle-removing capability of the channel flow by introducing higher surface-averaged removal forces and particle resuspension *** but not least,the increase of resuspension rate is especially significant for the smaller,micron-scale particles which are otherwise hardly disturbed by a VG-less channel flow,and such resuspension-enhancement effectgenerally subsides with increasing particle size.

关键词： Particle resuspension Vortexgenerator CFD Surface cleaning

Physical simulation of mixing on a C-H2 smelting reduction reactor with different tracer feeding positions

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Journal of Iron and Steel Research International 2020年第9期27卷 1018-1034页

作者： jin-yin xie Bo Wang Jie-yu Zhang State Key Laboratory of Advanced Special Steel and Shanghai Key Laboratory of Advanced Ferrometallurgy School of Materials Science and EngineeringShanghai UniversityShanghai 200072China

With the growing demand for energy saving,emission reduction,and green metallurgy,we had designed a new C-H2 smelting reduction *** order to solve the key problem that the heat transfer efficiency from high temperature oxidation zone in upper region to low temperature reduction zone in lower region is low in traditional metallurgical reduction reactor,a water simulation was adopted to optimize the mean residence time and to improve the transmission efficiency within the *** to the modified Froude similarity,a water model experimental reactor with a ratio of 1:1 to the prototype was *** the prototype,the feed port was used to feed preheated ore and *** order to simulate the effect of different feeding positions of the tracer on the mixing behavior in the molten pool,four points of tracer feeding position were arranged for a systematic *** the same time,based on double-row side nozzle with thick slag layer in a C-H2 smelting reduction reactor,nine influencing factors,including relative angle between upper and lower side nozzles,were *** experimental results showed that the tracer feeding position had a great influence on the mean residence time,and the relative angle also had a great influence on tracer feeding ***,through comprehensive analysis,the optimal condition parameters were obtained under different tracer feeding *** results provide valuable help for the design and optimization of the C-H2 smelting reduction reactor.

关键词： Smelting reduction reactor Tracer feeding position Double-row side blowing Mean residence time Relative angle Horizontal angle Vertical angle

Learning Dual-Layer User Representation for Enhanced Item Recommendation

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Computers, Materials & Continua 2024年第7期80卷 949-971页

作者： Fuxi Zhu jin xie Mohammed Alshahrani Applied Research Center of Artificial Intelligence Wuhan CollegeWuhan430212China College of Computer Science South-Central MINZU UniversityWuhan430074China Unmanned.Company Riyadh11564Saudi Arabia

User representation learning is crucial for capturing different user preferences,but it is also critical challenging because user intentions are latent and dispersed in complex and different patterns of user-generated data,and thus cannot be measured ***-based data models can learn user representations by mining latent semantics,which is beneficial to enhancing the semantic function of user ***,these technologies only extract common features in historical records and cannot represent changes in user ***,sequential feature can express the user’s interests and intentions that change time by *** the sequential recommendation results based on the user representation of the item lack the interpretability of preference *** address these issues,we propose in this paper a novel model with Dual-Layer User Representation,named DLUR,where the user’s intention is learned based on two different layer ***,the latent semantic layer adds an interactive layer based on Transformer to extract keywords and key sentences in the text and serve as a basis for *** sequence layer uses the Transformer model to encode the user’s preference intention to clarify changes in the user’s ***,this dual-layer user mode is more comprehensive than a single text mode or sequence mode and can effectually improve the performance of *** extensive experiments on five benchmark datasets demonstrate DLUR’s performance over state-of-the-art recommendation *** addition,DLUR’s ability to explain recommendation results is also demonstrated through some specific cases.

关键词： User representation latent semantic sequential feature interpretability

Production,Modifi cation and Bio-Applications of Magnetic Nanoparticles Gestated by Magnetotactic Bacteria

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Nano Research 2009年第4期2卷 261-278页

作者： jin xie Kai Chen Xiaoyuan Chen Department of Radiology Bio-X ProgramStanford University School of MedicineStanfordCA 94305-5484USA

Magnetotactic bacteria(MTB)were first discovered by Richard *** in 1975,and this led to the discovery of a wide collection of microorganisms with similar features i.e.,the ability to internalize Fe and convert it into magnetic nanoparticles,in the form of either magnetite(Fe_(3)O_(4))or greigite(Fe_(3)S_(4)).Studies showed that these particles are highly crystalline,monodisperse,bioengineerable and have high magnetism that is comparable to those made by advanced synthetic methods,making them candidate materials for a broad range of *** this review article,the history of the discovery of MTB and subsequent efforts to elucidate the mechanisms behind the magnetosome formation are briefly *** focus is on how to utilize the knowledge gained from fundamental studies to fabricate functional MTB nanoparticles(MTB-NPs)that are capable of tackling real biomedical problems.

关键词： Magnetotactic bacteria(MTB) magnetosome bio-application magnetic resonance imaging(MRI)

Statistical considerations for high throughput screening data

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Frontiers in Biology 2010年第4期5卷 354-360页

作者： Xian-jin xie Division of Biostatistics Department of Clinical Sciences&Simmons Comprehensive Cancer CenterThe University of Texas Southwestern Medical CenterDallasTexas 75390USA

High throughput screening(HTS)is a widely used effective approach in genome-wide association and large scale protein expression studies,drug discovery,and biomedical imaging *** to accurately identify candidate‘targets’or biologically meaningful features with a high degree of confidence has led to extensive statistical research in an effort to minimize both false-positive and false-negative rates.A large body of literature on this topic with in-depth statistical contents is *** examine currently available statistical methods on HTS and aim to summarize some selected methods into a concise,easy-tofollow introduction for experimental biologists.

关键词： high throughput screen false-positive rate false-negative rate target discovery predictive modeling

Multiplicative Mappings of Rings

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Acta Mathematica Sinica,English Series 2006年第4期22卷 1017-1020页

作者： Fang Yan LU jin Hai xie Department of Mathematics Suzhou University Suzhou 215006 P. R. China

Let R and F be arbitrary associative rings. A mapping φ of R onto F is called a multiplicative isomorphism if φ is bijective and satisfies φ（xy） = φ（x）φ（y） for all x, y ∈ R. In this short note, we establish a condition on R, in the case where R may not contain any non-zero idempotents, that assures that φ is additive, which generalizes the famous Martindale＇s result. As an application, we show that under a mild assumption every multiplicative isomorphism from the radical of a nest algebra onto an arbitrary ring is additive.

关键词： Multiplicative isomorphisms Additivity Idempotents

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