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Region coverage control for multiple stratospheric airships with combined self-/event-triggered mechanism

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Defence Technology（防务技术） 2023年第6期24卷 254-268页

作者： yi-fei zhang Ming Zhu Tian Chen Ze-wei Zheng School of Aeronautic Science and Engineering Beihang UniversityBeijing100191China Institute of Unmanned System Beihang UniversityBeijing100191China School of Electronic and Information Engineering Beihang UniversityBeijing100191China School of Automation Science and Electrical Engineering Beihang UniversityBeijing100191China

The region coverage control problem of multiple stratospheric airships system is firstly addressed in this *** it,we propose a two-layer control framework with the artificial potential field(APF)-based region coverage control law and the adaptive tracking control *** APF-based region coverage control law ensures the coverage task is achieved until every single stratospheric airship ends up performing station keeping where near the respective global minimum point,in which an innovative solution to the local minimum problem is put *** adaptive tracking control law is designed to realize motion control using tracking the desired velocity and angular velocity given by coverage control law,with the consideration of several practical control problems as unknown individual differences and external *** save resources,the combined self-/event-triggered mechanism designed therein significantly reduces the times of state information transmission and control law *** effectiveness of the proposed control framework is verified through simulations.

关键词： Formation coverage control Combined self-/event-triggered control Improved artificial potential field

An experimental review of open heavy flavor and quarkonium production at RHIC

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Nuclear Science and Techniques 2020年第8期31卷 72-103页

作者： Ze-Bo Tang Wang-Mei Zha yi-fei zhang State Key Laboratory of Particle Detection and Electronics University of Science and Technology of ChinaHefei 230026China Department of Modern Physics University of Science and Technology of ChinaHefei 230026China

Open heavy flavors and quarkonia are unique probes of the hot–dense medium produced in heavy-ion collisions. Their production in p+p collisions also constitutes an important test of QCD. In this paper, we review selected results on the open heavy flavors and quarkonia generated in the p+p and heavy-ion collisions at the Relativistic Heavy Ion Collider. The physical implications are also discussed.

关键词： Heavy flavor Heavy quark Quarkonium Quark–gluon plasma Heavy-ion collisions QCD

Non-extensive statistical distributions of charmed meson production in Pb-Pb and pp(p)collisions

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Nuclear Science and Techniques 2021年第10期32卷 79-87页

作者： Yuan Su Yong-Jie Sun yi-fei zhang Xiao-Long Chen State Key Laboratory of Particle Detection and Electronics University of Science and Technology of ChinaHefei 230026China Department of Modern Physics University of Science and Technology of ChinaHefei 230026China

The mid-rapidity transverse momentum spectra of charmed mesons in Pb–Pb and pp(p)collisions are analyzed using the Tsallis–Pareto distribution derived from non-extensive *** provide uniform descriptions of both small and large systems over a wide range of collision energies and hadron transverse *** establishing the relationship between the event multiplicity and Tsallis parameters,we observe that there is a signifi-cant linear relationship between the thermal temperature and Tsallis q parameter in Pb–Pb collisions at √sNN=2.76 TeV and 5.02 ***,the slope of the T–(q-1)parameter plot is positively correlated with the hadron *** addition,charmed mesons have a higher thermal temperature than light hadrons at the same q-1,indicat-ing that the charm flavor requires a higher temperature to reach the same degree of non-extensivity as light flavors in heavy-ion *** same fit is applied to the trans-verse momentum spectra of charmed mesons in pp(p)collisions over a large energy range using the Tsallis–Pareto *** is found that the thermal temperature increases with system energy,whereas the q parameter becomes saturated at the pp(p)limit,q-1=0.142±*** addition,the results of most peripheral Pb–Pb collisions are found to approach the pp(p)limit,which suggests that more peripheral heavy-ion collisions are less affected by the medium and more similar to pp(p)collisions.

关键词： Charmed meson Non-extensive statistics Tsallis-Pareto distribution QGP Heavy-ion collision

Effect of Soda Ash on Properties of Mold Flux and Mineralogical Structures of Flux Film

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Journal of Iron and Steel Research International 2016年第3期23卷 197-202页

作者： Xiu-li HAN yi-fei zhang Lei LIU Li-na LIU Han zhang College of Mining Engineering North China University of Science and Technology

During continuous casting,properties of mold flux and mineralogical structures of flux film play important roles in controlling steel *** effect of soda ash on the physical properties and crystallization characteristics of mold flux was investigated using process mineralogy,including polarizing microscopy,X-ray diffraction,and electron microprobe,*** flux was mainly prepared using cement clinker and industrial mineral materials under laboratory conditions,and the mineralogical structures of the flux film were systematically identified and quantitatively *** results showed that,by increasing the soda ash content from 10mass% to 18mass%,the crystallization temperature,critical cooling rate and crystallization ratio of the flux film decreased,but the crystallization ratio still reached 75% after adding soda ash,and the mineral compositions and microstructures of the flux film changed *** the soda ash content exceeded 14mass%,the critical cooling rate and the crystallization ratio decreased slightly,whereas the mineral content of the flux film changed evidently,with a large amount of cuspidine precipitation and a significant decrease in the wollastonite content until it reached zero,which resulted in deterioration of the lubrication of the flux film.

关键词： soda ash mold flux flux film crystallization property mineralogical structure

Network selection policy in multi-radio access environment using stochastic control theory

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The Journal of China Universities of Posts and Telecommunications 2011年第4期18卷 98-103页

作者： WEI yi-fei SONG Mei zhang Yong LIU Ning-ning School of Electronic Engineering Beijing University of Posts and Telecommunications Beijing 100876 China

Network selection is crucial in improving the performance of heterogeneous wireless access systems. Most of previous work on network selection or radio resource allocation concentrates on the capability of each available network and ignores the time-varying nature of wireless media due to channel fading. However, the channel condition determines the state of each wireless network and plays a vital role in ensuring quality of service in multi-radio access environment. In this article, we propose a network selection policy using stochastic control theory considering the time-varying and stochastic character of wireless channels. The proposed scheme selects one network among different alternatives in each decision epoch according to the channel state of each network, which is modeled as finite-state Markov channel, with the objectives of increasing the data-rate, decreasing the bit error rate and minishing the delay. The procedure of network selection is formulated as a stochastic control problem, which can be solved using linear programming and primal-dual index heuristic algorithm. Simulation results are presented to show that network selection has great impact on the system performance, and the proposed scheme can improve the performance significantly.

关键词： network selection multi-radio finite-state Markov channel stochastic control

Cooperative Supramolecular Polymerization of Propeller-Shaped Triphenylamine Cyanostilbenes for Explosive Detection

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Chinese Journal of Polymer Science 2023年第4期41卷 585-592,I0009页

作者： Long-Yu Guang Zhi-Feng Zhou yi-fei zhang Lai-Wei Gao Feng Wang Rui Liao CAS Key Laboratory of Soft Matter Chemistry Department of Polymer Science and EngineeringUniversity of Science and Technology of ChinaHefei230026China Clinical Laboratory The Second People’s Hospital of HefeiHefei230011China

Self-assembly ofπ-conjugated compounds into supramolecular polymers has received considerable attention because of their intrinsic scientific interests and technological *** compared toπ-conjugated rods,discotics,and macrocycles,propeller-shapedπ-conjugated molecules have been less exploited to form long-range-ordered supramolecular *** a novel type of supramolecular polymers has been constructed on the basis of propeller-shaped triphenylamine *** designed compound adopts nucleation-elongation cooperative mechanism for the supramolecular polymerization process,because of the participation of three-fold hydrogen bonds between the neighbouring *** supramolecular polymeric state displays amplified chirality and enhanced emission than those in the monomeric *** resulting supramolecular polymers exhibit severe emission quenching upon addition of 2,6-dinitrotoluene,ascribed to photoinduced electron transfer from the triphenylamine cyanostilbenes to the explosive *** current study proves the feasibility to supramolecular polymerize propeller-likeπ-conjugated molecules,serving as a promising type of explosive sensor owing to their guest encapsulation and signal amplification capabilities.

关键词： Supramolecular polymers D-π-A molecules Supramolecular chirality Fluorescence Explosive detection

ASICla contributes to the symptom of pain in a ra＇ model of chronic prostatitis

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Asian Journal of Andrology 2018年第3期20卷 300-305页

作者： Song Fan Zong-Yao Hao Li zhang Jun Zhou yi-fei zhang Shen Tai Xian-Sheng zhang Chao-Zhao Liang Department of Urology Institute of Urology Anhui Medical University Hefei 230022 China The First Affiliated Hospital of Anhui Medical University Hefei 230022 China

This study aims to validate our hypothesis that acid-sensing ion channels （ASICs） may contribute to the symptom of pain in patients with chronic prostatitis （CP）. We first established a CP rat model, then isolated the L5-S2 spinal dorsal horn neurons for further studies. ASICla was knocked down and its effects on the expression of neurogenic inflammation-related factors in the dorsal horn neurons of rat spinal cord were evaluated. The effect of ASICla on the Ca2＋ ion concentration in the dorsal horn neurons of rat spinal cord was measured by the intracellular calcium （[Ca~＊]i） intensity. The effect of ASICla on the p38/mitogen-activated protein kinase （MAPK） signaling pathway was also determined. ASICla was significantly upregulated in the CP rat model as compared with control rats. Acid-induced ASICla expression increased [Ca2＋]i intensity in the dorsal horn neurons of rat spinal cord. ASICla also increased the levels of neurogenic inflammation-related factors and p-p38 expression in the acid-treated dorsal horn neurons. Notably, ASICla knockdown significantly decreased the expression of pro-inflammatory cytokines. Furthermore, the levels of p-p38 and pro-inflammatory cytokines in acid-treated dorsal horn neurons were significantly decreased in the presence of PcTx-1, BAPTA-AM, or SB203580. Our results showed that ASIC1a may contribute to the symptom of pain in patients with CP, at least partially, by regulating the p38/MAPK signaling pathway.

关键词： ASICla chronic prostatitis pain symptom

Cleaning of carbon-contaminated optics using O2/Ar plasma

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Nuclear Science and Techniques 2017年第9期28卷 16-20页

作者： yi-fei zhang Hong-Xin Luo Zhi Guo Xiang-Jun Zhen Ming Chen Jun-Nan Liu Shanghai Institute of Applied Physics Chinese Academy of Sciences Shanghai 201204 China

Cleaning of carbon-contaminated beamline optics was studied by RF plasma discharge process using O_2/Ar. Carbon-coated samples were prepared, and through their cleaning processes key parameters were determined,such as the optimal RF output power, mixing rates of O_2/Ar, and chamber vacuum. Considerations were made against possible adverse effects in cleaning the beamline optics, such as comparing the roughness of samples before and after cleaning, and possible detrimental kinetic effects on cable insulation. Under the cleaning parameters to clean the beamline optics, the thickness of removed carbon film and the change in beamline photon flux were analyzed.

关键词：等离子体清洗光学参数碳污染射频等离子体氧表面粗糙度动力学效应光束线

Multiplicity dependence of charged particle,? meson, and multistrange particle productions in p + p collisions at s^(1/2) = 200 GeV from PYTHIA simulation

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Nuclear Science and Techniques 2018年第9期29卷 236-241页

作者： Sheng-Hui zhang Long Zhou yi-fei zhang Ming-Wei zhang Cheng Li Ming Shao Yong-Jie Sun Ze-Bo Tang University of Science and Technology of China Hefei 230026China

We report the multiplicity dependence of charged particle production for the n~±, K~±, p, , and ? mesons at |y|<1:0 in p + p collisions at s^(1/2) = 200 GeV from a PYTHIA simulation. The impact of multiple parton ... 详细信息

We report the multiplicity dependence of charged particle production for the n~±, K~±, p, , and ? mesons at |y|yields as a function of p_T with respect to the multiplicity. No obvious particle species dependence of the splitting is *** multiplicity dependence of the ratios Kˉ/πˉ, K^+/π^+,/πˉ, p/π^+, and K_s^0 at mid-rapidity in p+ p collisions is found to follow a tendency similar to that in Au t Au collisions at (s_(NN))^(1/2) = 200 GeV at the Relativistic Heavy Ion Collider, indicating similar underlying initial production mechanisms despite the differences in the initial colliding systems.

关键词： Particle production Heavy-ion collisions Small system Multiple parton interactions Gluon contributions