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A Note on Equilibrium of Eventually Strongly Monotone Skew-product Semiflows

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Acta Mathematicae Applicatae Sinica 2010年第2期26卷 307-310页

作者： Xi-liang Li zuo-huan zheng Shandong Institute of Business and Technology Yantai 264005 China Institute of Applied Mathematics Academy of Mathematics and Systems Science Chinese Academy of SciencesBeijing 100190 China

In this paper, we show that for an eventually strongly monotone skew-product semiflow τ, the strict ordering on Ec （the set consisting of continuous equilibria of τ） implies the strong one.

关键词： continuous equilibrium eventually strongly monotone skew-product semiflow

Hybrid ants-like search algorithms for P2P media streaming distribution in ad hoc networks

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第8期8卷 1191-1198页

作者： zuo Dong-hong DU Xu YANG Zong-kai Department of Electronics and Information Engineering Huazhong Univerisity of Science and Technology Wuhan 430074 China

Media streaming delivery in wireless ad hoc networks is challenging due to the stringent resource restrictions,po-tential high loss rate and the decentralized architecture. To support long and high-quality streams,one viable approach is that a media stream is partitioned into segments,and then the segments are replicated in a network and served in a peer-to-peer(P2P) fashion. However,the searching strategy for segments is one key problem with the approach. This paper proposes a hybrid ants-like search algorithm(HASA) for P2P media streaming distribution in ad hoc networks. It takes the advantages of random walks and ants-like algorithms for searching in unstructured P2P networks,such as low transmitting latency,less jitter times,and low unnecessary traffic. We quantify the performance of our scheme in terms of response time,jitter times,and network messages for media streaming distribution. Simulation results showed that it can effectively improve the search efficiency for P2P media streaming distribution in ad hoc networks.

关键词： Ad hoc networks Media streaming distribution Search algorithms Peer to peer (P2P)

Tenant-based access control model for multi-tenancy and sub-tenancy architecture in Software-as-a-Service

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Frontiers of Computer Science 2017年第3期11卷 465-484页

作者： Qiong zuo Meiyi XIE Guanqiu QI hong ZHU School of Computer Science and Technology Huazhong University of Science and Technology Wuhan 430074 China School of Computing Informatics and Decision Systems Engineering Arizona State University Tempe AZ 85287 USA

Software-as-a-Service （SaaS） introduces multi- tenancy architecture （MTA）. Sub-tenancy architecture （STA）, is an extension of MTA, allows tenants to offer services for subtenant developers to customize their applications in the SaaS infrastructure. In a STA system, tenants can create sub- tenants, and grant their resources （including private services and data） to their subtenants. The isolation and sharing re- lations between parent-child tenants, sibling tenants or two non-related tenants are more complicated than those between tenants in MTA. It is important to keep service components or data private, and at the same time, allow them to be shared, and support application customizations for tenants. To ad- dress this problem, this paper provides a formal definition of a new tenant-based access control model based on administra- tive role-based access control （ARBAC） for MTA and STA in service-oriented SaaS （called TMS-ARBAC）. Autonomous areas （AA） and AA-tree are proposed to describe the auton- omy of tenants, including their isolation and sharing relation- ships. Authorization operations on AA and different resource sharing strategies are defined to create and deploy the access control scheme in STA models. TMS-ARBAC model is ap- plied to design a geographic e-Science platform.

关键词： Software-as-a-Service (SaaS) multi-tenancy architecture (MTA) sub-tenancy architecture (STA) rolebased access control (RBAC) model tenant-based access control model

Thermal deformation behavior and microstructure evolution of modified IN617 alloy with different initial states

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Journal of Iron and Steel Research International 2021年第10期28卷 1315-1328页

作者： Qi Li Xin-liang Jiang zheng-zong Chen zheng-dong Liu Liang zuo Key Laboratory for Anisotropy and Texture of Materials Ministry of EducationNortheastern UniversityShenyang110819LiaoningChina Erzhong(Deyang)Heavy Equipment Co. Ltd.Deyang618000SichuanChina Institute for Special Steels China Iron and Steel Research InstituteBeijing100081China

The thermal deformation behaviors of the as-cast and wrought modified IN617 nickel-based heat-resistant alloys at different temperatures(1000–1180℃)and strain rates(0.01–1 s^(−1))were *** constitutive equation was established to describe the relationship of the flow stress,temperature,and strain rate during thermal *** effect of the thermal deformation conditions on the microstructure evolution of alloys was studied using electron backscatter *** results revealed that the thermal deformation activation energy of the as-cast alloy was greater than that of the wrought *** dynamic recrystallization(DRX)process is slow at intermediate strain rate(0.1 s^(−1))due to the comprehensive influence of various factors,such as the critical strain of DRX nucleation and stored *** DRX volume fraction increases with the improvement of deformation *** varied dynamic softening mechanisms induce the different thermal deformation behaviors of as-cast and wrought *** dynamic recovery,discontinuous dynamic recrystallization(DDRX)and nucleation at slip zone caused by strain incompatibility in grains were observed during thermal deformation of as-cast *** the process of thermal deformation of wrought alloys,DDRX was the primary dynamic crystallization *** continuous dynamic recrystallization was an auxiliary nucleation mechanism.

关键词： Nickel-based heat-resistant alloy Initial alloy state Thermal deformation Microstructure evolution Dynamic recrystallization nucleation mechanism

Inhibitive effects of chlortetracycline on performance of the nitritation-anaerobic ammonium oxidation(anammox)process and strategies for recovery

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Journal of Environmental Sciences 2018年第8期30卷 29-36页

作者： hong Yao Huayu Li Jing Xu Lushen zuo Beijing Key Laboratory of Aqueous Typical Pollutants Control and Water Quality Safeguard Department of Municipal and Environmental Engineering Beijing Jiaotong University

The short-and long-term effects of chlortetracycline（CTC） on the nitritation-anaerobic ammonium oxidation（anammox） process were evaluated. The half maximal inhibitory concentration of CTC in the batch tests of the nitritation-anammox process was 278.91 mg/L at an exposure time of 12 hr. The long-term effects of CTC on the process were examined in a continuous-flow nitritation-anammox reactor. Within 14 days, the nitrogen removal rate significantly decreased from 0.61 to 0.25 kg N/m^3/day with 60 mg/L CTC in the *** performance suppressed by CTC barely recovered, even after CTC was removed from the influent. Furthermore, the inhibition of CTC also reduced the relative abundance of ammonium oxidizing bacteria（AOB） and anaerobic ammonium oxidizing bacteria（An AOB）in the reactor, resulting in both a decreased amount of and an imbalance between AOB and An AOB. When fresh anammox sludge was reseeded into the nitritation-anammox reactor,the nitrogen removal rate recovered to 0.09 ± 0.03 kg N/m3/day.

关键词： Nitritation-anammox process Anaerobic ammonium oxidizing bacteria (AnAOB) Ammonium oxidizing bacteria (AOB) Chlortetracycline

Stratigraphy and Zircon Provenance of a Late Paleoproterozoic Terrestrial Sequence underlying the Xiong'er Volcanics in the Southern North China Craton

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Acta Geologica Sinica(English Edition) 2022年第5期96卷 1502-1515页

作者： SUN Fengbo zheng Deshun zuo Pengfei LIU Weiqing Henan Polytechnic University JiaozuoHenan 454003China

The late Paleoproterozoic Dagushi Formation comprises a fluvial-lacustrine succession and represents the initial fill of the Xiong'er Basin in the southern North China *** integrated outcrop surveys and detrital zircon UPb-Hf dating,this study examines the provenance and depositional setting of the Dagushi *** major depositional facies,including braided channel,distributary channel,subaqueous stream/mouth bar,pro-delta and shallow lake,were identified,based on lithofacies and *** were interpreted as representing a braided river deltalacustrine *** ages of the last metamorphic event of the basement,covering volcanics and the youngest zircon together constrain a depositional age of ca.1.79 Ga for the Dagushi *** age distributions reveal a provenance change from ca.2.7–2.5 Ga rocks in the lower part,to ca.2.3–1.9 Ga sources in the middle-upper part of the Dagushi *** the vertical sedimentology,this provenance change could be induced by the rising water-level caused by a tectonic *** ca.2.7–2.5 Ga zircons are suggested to be locally sourced from the late Neoarchean–Paleoproterozoic metamorphic *** northeast Zhongtiao Mts area(current co-ordinates)is supposed to have appeared as a paleo-uplift and served as a source area for the Paleoproterozoic *** Dagushi Formation records an early‘underfilled'stage of the Xiong'er Rift.

关键词： late Paleoproterozoic Dagushi Formation sedimentology zircon geochronology provenance Xiong'er Rift

Almost Periodic Solutions by the Harmonic Balance Method

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Acta Mathematicae Applicatae Sinica 2022年第4期38卷 943-954页

作者： Ji-feng CHU zuo-huan zheng Zhe ZHOU Department of Mathematics Shanghai Normal UniversityShanghai 200234China Academy of Mathematics and Systems Science Chinese Academy of SciencesBeijing 100190China School of Mathematical Sciences University of Chinese Academy of SciencesBeijing 100049China College of Mathematics and Statistics Hainan Normal UniversityHaikou 571158China

We consider non-autonomous ordinary differential equations in two *** is the one-dimensional case that admits a condition of hyperbolicity,and the other one is the higher-dimensional case that admits an exponential *** differential equations of this kind,we give a rigorous treatment of the Harmonic Balance Method to look for almost periodic solutions.

关键词： almost periodic solution Harmonic balance method exponential dichotomy

STUDY ON PHASE-SEPARATION OF PMMA/SAN BLENDS INDUCED BY GLASS BEADS THROUGH DYNAMIC RHEOLOGICAL MEASUREMENTS

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Chinese Journal of Polymer Science 2006年第1期24卷 53-60页

作者： Miao Du Jian-hua Gong Min zuo Qiang zheng Department of Polymer Science and Engineering Zhejiang University Hangzhou 310027 China State Key Laboratory of Fluid Power Control and Transmission Zhejiang University Hangzhou 310027 China

Based on the premise that the addition of glass beads （GB） could hardly influence the linear viscoelasticity in low frequency （ω） region for homogeneous polymer systems, the dynamic rheological behaviors of unfilled and filled poly（methyl methyacrylate）（PMMA）/poly（styrene-co-acrylonitrile）（SAN） blends were studied in order to explore the effect of GB on the phase-separation of binary polymer matrix. Results show that GB has an induced effect on the phase-separation, which embodies that the phase-separation temperature （Ts） of PMMA/SAN blend filled with GB is lower than that of the unfilled system. The higher content of GB, the higher is the ＂secondary plateau＂ of ω in the terminal region of storage modulus （G＇） versus ω plot. The ＂secondary plateau＂ appearing in the terminal region is attributed to the phase-separation of PMMA/SAN blends and it becomes more fiat for filled polymer blends under the same conditions. However, it is suggested that this kind of ＂induced effect＂ is related to the GB content; the higher content of GB particles might enhance the interaction between the particles and polymer matrix. Moreover, it is found that the addition of GB also has an influence more or less on the morphology and domain size of polymer matrix. It is believed that the plot of dynamic viscosity （η＇） versus the loss viscosity （η＂） is sensitive to examine the effect induced by GB on the phase-separation of binary polymer matrix.

关键词： PMMA/SAN blends Glass beads Phase-separation Rheological behavior. poly(styrene-co-acrylonitrile)

New perspectives in free nitrous acid (FNA) uses for sustainable wastewater management

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Frontiers of Environmental Science & Engineering 2024年第2期18卷 161-168页

作者： Zhiqiang zuo Min zheng Tao Liu Yongzhen Peng Zhiguo Yuan National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology Engineering Research Center of BeijingBeijing University of TechnologyBeijing 100124China Australian Centre for Water and Environmental Biotechnology The University of QueenslandSt.LuciaQLD 4072Australia Water Research Centre School of Civil and Environmental EngineeringUniversity of New South WalesSydneyNew South Wales 2052Australia Department of Civil and Environmental Engineering The Hong Kong Polytechnic UniversityHung HomKowloonHong Kong 999077China School of Energy and Environment City University of Hong KongHong Kong 999077China

The biocidal effects of free nitrous acid (FNA) have found applications in multiple units in an urban wastewater system, including sewer networks, wastewater treatment processes, and sludge treatment processes. However, these applications are associated with chemical costs as both nitrite and acid are needed to produce FNA at the required levels. The recent discovery of novel acid-tolerant ammonia oxidizers offers the possibility to produce FNA from domestic wastewater, enabling the development of next-generation FNA-based technologies capable of achieving self-sustaining FNA production. In this study, we focus on the concept of in situ FNA generation facilitated by acid-tolerant ammonia oxidizers and highlight the multiple benefits it creates, after a brief review of the historical development of FNA-based technologies. We will discuss how wastewater systems can be made more energy-efficient and sustainable by leveraging the potential of acid-tolerant ammonia oxidizers.

关键词： Free nitrous acid Acid-toler antammonia oxidizer In situ generationl Wastewater management