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Performance analysis of optical multicast in a new switching structure

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The Journal of China Universities of Posts and Telecommunications 2007年第3期14卷 43-47页

作者： jia Peng zhang Jie GU Wan-yi Key Laboratory of Optical Communication and Lightwave Technologies Ministry of Education Beijing University of Posts and TelecommunicationsBeijing 100876 China

The emergence of new services demands multicast function in optical network. Because of the high cost and complex architecture of multicast capable （MC） node, splitter- sharing switch structure is introduced in which the light splitters are shared by all input signals. To accommodate to this situation, by extending resource ReSerVation protocol-traffic engineering （RSVP-TE） and open shortest path first-traffic engineering （OSPF-TE）, a new optical multicast mechanism is provided and the signaling flow and its finite state machine model are given. At the same time, a multicast routing algorithm in splitter-sharing optical network and a changing link weight policy to balance network traffic are proposed. Simulations in NSFNET show no matter with or without wavelength converters, when the number of splitters is 25% of that demanded by traditional MC nodes, the multicast performance has been close to the ideal circumstance. Wavelength converters and changing link weight help much in improving the traffic performance when the number of splitters is adequate.

关键词： splitter-sharing optical multicast optical network wavelength converter

A one-dimensional transport model for multi-component solute in saturated soil

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Water Science and Engineering 2018年第3期11卷 236-242页

作者： Zhi-hong zhang jia-pei zhang Zhan-ying Ju Min Zhu Key Laboratory of Urban Security and Disaster Engineering of Ministry of Education Beijing University of Technology

A modified multi-component solute diffusion equation described with diffusion flux was derived in detail based on the classical MaxwellStefan diffusion theory. The friction between the solute species and the soil skeleton wall, which is proportional to the relative velocity between the solute species and the soil skeleton, is introduced. The chemical potential gradient is considered the driving force. A one-dimensional model for transport of multi-component solute in saturated soil was developed based on the modified diffusion equation and the modified competitive Langmuir adsorption equation. Numerical calculation of a case of two heavy metal ion species, which was chosen as an example, was carried out using the finite element software COMSOL Multiphysics. A comparative analysis was performed between the multi-component solute transport model developed in this study and the convection-diffusion transport model of single-component solute based on Fick's law. Simulation results show that the transport behavior of each species in a multi-component solute system is different from that in a single-component system, and the friction characteristics considered in the developed model contribute to obstructing the movement of each solute component. At the same time,the influence of modified competitive Langmuir adsorption on solute transport was investigated. These research results can provide strong theoretical support for the design of antifouling barriers in landfills and the maintenance of operation stability.

关键词： Multi-component solute Maxwell-Stefan diffusion Competitive adsorption Friction Transport

Stable Isotope Studies of Crop Carbon and Water Relations:A Review

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Agricultural Sciences in China 2009年第5期8卷 578-590页

作者： zhang Cong-zhi zhang jia-bao ZHAO Bing-zi zhang Hui HUANG Ping State Experimental Station of Agro-Ecosystem in Fengqiu/State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil Science Chinese Academy of Sciences Nanjing 210008 P.R.China Graduate School of the Chinese Academy of Sciences Beijing 100049 P.R.China

Crop carbon and water relations research is important in the studies of water saving agriculture, breeding program, and energy and material cycles in soil plant atmosphere continuum （SPAC）. The purpose of this paper is to review the current state of knowledge on stable isotopes of carbon, oxygen, and hydrogen in the research of crop carbon and water relations, such as carbon isotope discrimination （△^13C） during carbon fixation process by photosynthesis, application of △^13C in crop water use efficiency （WUE） and breeding programs, oxygen isotope enrichment during leaf water transpiration, CO2 fixation by photosynthesis and release by respiration, application of hydrogen isotope composition （619） and oxygen isotope composition （6180） for determination of water source used by a crop, stable isotope coupling Keeling plot for investigating the carbon and water flux in ecosystem, energy and material cycle in SPAC and correlative integrative models on stable isotope. These aspects contain most of the stable isotope researches on crop carbon and water relations which have been widely explored internationally while less referred in China. Based on the reviewed literatures, some needs for future research are suggested.

关键词： carbon fixation crop review stable isotopes water relations

On properties of mass transfer in an Algol-type binary system:an example of VV Vir

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Research in Astronomy and Astrophysics 2014年第2期14卷 179-192页

作者： jia zhang Sheng-Bang Qian Lin-Qiao jiang Yunnan Observatories Chinese Academy of Sciences Key Laboratory of the Structure and Evolution of Celestial Objects Chinese Academy of Sciences University of Chinese Academy of Sciences

Some properties of mass transfer within a semi-detached binary system are discussed based on an example of VV Vir. The observations and analysis of VV Vir show that it is a semi-detached binary system with the less massive cooler component filling its Roche lobe, which is also called an Algol-type binary system. Based on the parameters of this semi-detached binary, a theoretical study on the mass flow is carded out, including the trajectory of the mass flow, the position, radius and temperature of the impact spot caused by the mass flow, the inconsistent form of the mass flow and the possibly huge rate of energy transfer carried by the mass flow. Humps and distortions in light curves of VV Vir are deemed to be weak evidence for the theoretical results.

关键词： binaries eclipsing -- stars individual (VV Vir) -- techniques photo-metric

Casimir–Polder-Like Force for an Atom in Hartle–Hawking Vacuum outside a Schwarzschild Black Hole

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Chinese Physics Letters 2012年第8期29卷 38-41页

作者： zhang jia-Lin YU Hong-Wei Institute of Physics and Key Laboratory of Low Dimensional Quantum Structures and Quantum Control of Ministry of Education Hunan Normal UniversityChangsha 410081 Center for Nonlinear Science and Department of Physics Ningbo UniversityNingbo 315211

We calculate the energy level shift of a static ground state two-level atom interacting with fluctuating massless scalar fields in the Hartle–Hawking vacuum outside a Schwarzschild black *** is found that the energy level shift is position-dependent and gives rise to a force on the atom besides the classical gravitational *** force behaves like r^(-1)(r-2M)^(-1) for r approaching 2M,whereas it behaves like r^(-2) for large r.

关键词： force outside approaching

Curcumin Inhibits Proliferation of Renal Cell Carcinoma in vitro and in vivo by Regulating miR-148/ADAMTS18 through Suppressing Autophagy

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Chinese Journal of Integrative Medicine 2023年第8期29卷 699-706页

作者： XU Ben YUAN Chang-wei zhang jia-en Depatment of Urology Peking University First HospitalBeijing(100034)China

Objective: To explore the effect of curcumin on the proliferation of renal cell carcinoma and analyze its regulation mechanism. Methods: In RCC cell lines of A498 and 786-O, the effects of curcumin(2.5, 5, 10 μmo/L) on the proliferation were analyzed by Annexin V+PI staining. Besides, A498 was inoculated into nude mice to establish tumorigenic models, and the model mice were treated with different concentrations of curcumin(100, 200, and 400 mg/kg), once daily for 30 days. Then the tumor diameter was measured, the tumor cells were observed by hematoxylin-eosin staining, and the protein expressions of miR-148 and ADAMTS18were detected by immunohistochemistry. In vitro, after transfection of miR-148 mimics, miR-148 inhibitor or si-ADAMTS18 in cell lines, the expression of ADAMTS18 was examined by Western blotting and the cell survival rate was analyzed using MTT. Subsequently, Western blot analysis was again used to examine the autophagy phenomenon by measuring the relative expression level of LC3-Ⅱ/LC3-Ⅰ;autophagy-associated genes,including those of Beclin-1 and ATG5, were also examined when miR-148 was silenced in both cell lines with curcumin treatment. Results: Curcumin could inhibit the proliferation of RCC in cell lines and nude mice. The expressions of miR-148 and ADAMTS18 were upregulated after curcumin treatment both in vitro and in vivo(P<0.05). The cell survival rate was dramatically declined upon miR-148 or ADAMTS18 upregulated. However,si-ADAMTS18 treatment or miR-148 inhibitor reversed these results, that is, both of them promoted the cell survival rate. Conclusion: Curcumin can inhibit the proliferation of renal cell carcinoma by regulating the miR-148/ADAMTS18 axis through the suppression of autophagy in vitro and in vivo. There may exist a positive feedback loop between mi R-148 and ADAMTS18 gene in RCC.

关键词： curcumin renal cell carcinoma MiR-148 ADAMTS18 gene autophagy

Notes on Solvability and p-Supersolvability of Finite Groups

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Algebra Colloquium 2019年第1期26卷 139-146页

作者： jia zhang Tingting Qiu Long Miao Juping Tang School of Mathematics and Information China West Normal University Nanchong Sichuan 637009 China Yancheng Biological Engineering Higher Vocational Technology School Yancheng Jiangsu 224000 China School of Mathematical Sciences Yangzhou University Yangzhou Jiangsu 225002 China Wuxi Institute of Technology Wuxi Jiangsu 214121 China

A subgroup H of G is called M-supplemented in G if there exists a subgroup B of G such that G = HB and HiB < G for every maximal subgroup Hi of H. In this paper, we use M-suppiemented subgroups to study the structure of finite groups and obtain some new characterization about solvability and p-supersolvability for a fixed prime p. Some results in the literature are corollaries of our theorems.

关键词： M-supplemented subgroup composition factor solvable p-supersolvable

Boundary Conditions for NHEK through Effective Action Approach

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Chinese Physics Letters 2012年第4期29卷 23-26页

作者： CHEN Bin NING Bo zhang jia-Ju Department of Physics and State Key Laboratory of Nuclear Physics and TechnologyPeking UniversityBeijing 100871

We study the asymptotic symmetry group (ASG) of the near horizon geometry of extreme Kerr black hole through the effective action approach developed by Porfyriadis and Wilczek (arXiv:1007.1031v1[gr qc]).By requiring a finite boundary effective action,we derive a new set of asymptotic Killing vectors and boundary conditions,which are much more relaxed than the ones proposed by Matsuo Y et al.[***.B 825 (2010) 231],and still allow a copy of a conformal group as its *** the covariant formalism,the asymptotic charges are finite,with the corresponding central charge *** using the quasi-local charge and introducing a plausible cut-off,we find that the higher order terms of the asymptotic Killing vectors,which could not be determined through the effective action approach,contribute to the central charge as *** also show that the boundary conditions suggested by Guica et al.[***.D 80 (2009)124008] lead to a divergent first-order boundary effective action.

关键词： asymptotic boundary charge

Candidates of eclipsing multiples based on extraneous eclipses on binary light curves： KIC 7622486, KIC 7668648, KIC 7670485 and KIC 8938628

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Research in Astronomy and Astrophysics 2017年第3期17卷 1-12页

作者： jia zhang Sheng-Bang Qian jian-Duo He Yunnan Observatories Chinese Academy of Sciences Kunming 650216 China Key Laboratory of the Structure and Evolution of Celestial Objects Chinese Academy of Sciences Kunming 650216 China

Four candidates of eclipsing multiples, based on new extraneous eclipses found on Kepler binary light curves, are presented and studied. KIC 7622486 is a double eclipsing binary candidate with orbital periods of 2.2799960 d and 40.246503 d. The two binary systems do not eclipse each other in the line of sight, but there is mutual gravitational influence between them which leads to the small but definite eccentricity of 0.0035（0.0022） associated with the short 2.2799960 d period orbit. KIC 7668648 is a hierarchical quadruple system candidate, with two sets of solid 203 4- 5 d period extraneous eclipses and another independent set of extraneous eclipses. A clear and credible extraneous eclipse is found on the binary light curve of KIC 7670485 which makes it a triple system candidate. Two sets of extraneous eclipses with periods of about 390 d and 220 d are found on KIC 8938628 binary curves, which not only confirm the previous conclusion of the 388.5 4- 0.3 triple system, but also indicate new additional objects that make KIC 8938628 a hierarchical quadruple system candidate. The results from these four candidates will contribute to the field of eclipsing multiples.

关键词： binaries eclipsing - techniques photometric - methods observational