Publish in OALib Journal

ISSN: 2333-9721

APC: Only $99


Any time

2020 ( 39 )

2019 ( 355 )

2018 ( 2045 )

2017 ( 1961 )

Custom range...

Search Results: 1 - 10 of 118965 matches for " Jing Zhang "
All listed articles are free for downloading (OA Articles)
Page 1 /118965
Display every page Item
Threshold strategy to improve the images reconstructed by electrical impedance tomography  [PDF]
Xiaoyan Chen, Jing Zhang
Journal of Biosciences and Medicines (JBM) , 2013, DOI: 10.4236/jbm.2013.12008

Because of the illposedness of soft field, the quality of EIT images is not satisfied as expected. This paper puts forward a threshold strategy to decrease the artifacts in the reconstructed images by modifying the solutions of inverse problem. Threshold strategy is a kind of post processing method with merits of easy, direct and efficient. Reconstructed by Gauss-Newton algorithm, the simulation image’s quality is improved evidently. We take two performance targets, image reconstruction error and correlation coefficient, to evaluate the improvement. The images and the data show that threshold strategy is effective and achievable.

Performance of Nth Worst Full-Duplex Relay Selection over Nakagami-M Fading Channels  [PDF]
Jing Guo, Yujie Zhang
Int'l J. of Communications, Network and System Sciences (IJCNS) , 2017, DOI: 10.4236/ijcns.2017.108B004
The performance analysis of Nth worst relay selection for the full-duplex (FD) mode over Nakagami-m fading channels is studied. We assume the relay employs the amplify-and-forward (AF) protocol. The closed-form expres-sions for the outage performance in terms of the received signal-to-noise ratio cumulative distribution function are derived. In the high signal-to-noise ratio regime, asymptotic outage probability is also investigated. Based on these expressions, the effect of several important network parameters, i.e., the number of relays and the order of selected relay, as well as the quality of the relay links, source-relay links, relay-destination links, are analytically characterized. Finally, numerical results are provided to verify and illustrate our mathematical analysis.
Construction of Global Weak Entropy Solution of Initial-Boundary Value Problem for Scalar Conservation Laws with Weak Discontinuous Flux  [PDF]
Yihong Dai, Jing Zhang
American Journal of Computational Mathematics (AJCM) , 2017, DOI: 10.4236/ajcm.2017.74033
Abstract: This paper is concerned with the initial-boundary value problem of scalar conservation laws with weak discontinuous flux, whose initial data are a function with two pieces of constant and whose boundary data are a constant function. Under the condition that the flux function has a finite number of weak discontinuous points, by using the structure of weak entropy solution of the corresponding initial value problem and the boundary entropy condition developed by Bardos-Leroux-Nedelec, we give a construction method to the global weak entropy solution for this initial-boundary value problem, and by investigating the interaction of elementary waves and the boundary, we clarify the geometric structure and the behavior of boundary for the weak entropy solution.
Global Solution of a Nonlinear Conservation Law with Weak Discontinuous Flux in the Half Space  [PDF]
Xiaoqian Li, Jing Zhang
American Journal of Computational Mathematics (AJCM) , 2018, DOI: 10.4236/ajcm.2018.84026
This paper is concerned with the initial-boundary value problem of a nonlinear conservation law in the half space R+= {x |x > 0}
where a>0 , u(x,t) is an unknown function of x ∈ R+
and t>0 , u ± , um are three given constants satisfying um=u+u-
Influence of Biogeochemical Qualities of Shizuoka Water on the Degradation of PVC Shower Hose  [PDF]
Mst. Shamsun Nahar, Jing Zhang
Journal of Environmental Protection (JEP) , 2011, DOI: 10.4236/jep.2011.22024
Abstract: Recently, it has been report of polyvinyl chloride (PVC) shower hoses becoming hard and brittle throughout the eastern and middle portion of Shizuoka Prefecture, Japan. No reason has been identified for this phenomenon. The affected cities are located at the paper industries area. We have collected the stiffed hoses attached to shower faucets and examined them for chemical changes. In addition, we have analyzed the water quality of 11 affected cities in Shizuoka in an attempt to establish a probable bio-physico-chemical chain reaction that could cause such hose degradation. According to elemental analysis, oxygen-containing carbon-based plasticizers may leach out of the hose. As a result, the hoses lost flexibility after one year of use in Shizuoka. The organic nutrient (1,4-dioxane) was identified by GC-MS and the utmost number of the heterotrophic bacteria has been detected by PCR-DGGE in the shower water of Shizuoka. The study concludes that the plasticizer disappeared from the stiffed hose and the special characteristics of water in Shizuoka, consisting of organic nutrients, can be used for heterotrophic bacterial growth as a energy source at the shower water temperature, which allows prompt utilization of the plasticizer by increasing abundant bacteria, causing the brittleness of the PVC hose.
Analysis of Damaged Silicon Rubber Hose  [PDF]
Mosammad Shamsun Nahar, Jing Zhang
American Journal of Analytical Chemistry (AJAC) , 2011, DOI: 10.4236/ajac.2011.23044
Abstract: Recently, there have been many reports of silicon rubber (SR) hoses becoming brittle in juice factory within one month of purchase. The damage is a new phenomenon, and its cause is unknown. We have collected the damaged hoses attached to UHT sterilizer (ultra-high-temperature) in juice factory and examined them for chemical changes. In addition, we have analyzed the hose-washing chemicals (NaOH and HNO333) and the exposure UTH temperature have direct effect on the brittleness of the silicon hose in juice factory.
Global Convergence of a New Nonmonotone Algorithm
Jing Zhang
Research Journal of Applied Sciences, Engineering and Technology , 2013,
Abstract: In this study, we study the application of a kind of nonmonotone line search in BFGS algorithm for solving unconstrained optimization problems. This nonmonotone line search is belongs to Armijo-type line searches and when the step size is being computed at each iteration, the initial test step size can be adjusted according to the characteristics of objective functions. The global convergence of the algorithm is proved. Experiments on some well-known optimization test problems are presented to show the robustness and efficiency of the proposed algorithms.
A New Criterion for Affineness
Jing Zhang
ISRN Algebra , 2013, DOI: 10.1155/2013/786576
A New Criterion for Affineness
Jing Zhang
ISRN Algebra , 2013, DOI: 10.1155/2013/786576
Abstract: We show that an irreducible quasiprojective variety of dimension defined over an algebraically closed field with characteristic zero is an affine variety if and only if ( ) = 0 and ( ) = 0 for all , , where is any hypersurface with sufficiently large degree. A direct application is that an irreducible quasiprojective variety over is a Stein variety if it satisfies the two vanishing conditions. Here, all sheaves are algebraic. 1. Introduction We work over an algebraically closed field with characteristic zero. Affine varieties are important in algebraic geometry. J.-P. Serre introduced sheaf and cohomology techniques to algebraic geometry and discovered his well-known cohomology criterion ([1], [2, Chapter 2, Theorem 1.1]): a variety (or a Noetherian scheme) is an affine variety if and only if for all coherent sheaves on and all , . Goodman and Hartshorne proved that is an affine variety if and only if contains no complete curves and the dimension of the linear space is bounded for all coherent sheaves on [3]. Let be the completion of . In 1969, Goodman also proved that is affine if and only if after suitable blowing up of the closed subvariety on the boundary , the new boundary is a support of an ample divisor, where is the blowing up with center in ([4], [2, Chapter 2, Theorem 6.1]). For any quasiprojective variety , we may assume that the boundary is the support of an effective divisor with simple normal crossings by blowing up the closed subvariety in . is affine if is ample. So, if we can show the ampleness of , then is affine. There are two important criteria for ampleness according to Nakai-Moishezon and Kleiman ([5], [6, Chapter 1, Section 1.5]). Another sufficient condition is that if?? contains no complete curves and the linear system is base point free, then is affine [2, Chapter 2, Page 64]. Therefore, we can apply base point free theorem if we know the numerical condition of [6, Chapter 3, Page 75, Theorem 3.3]. Neeman proved that if is a quasicompact Zariski open subset of an affine scheme Spec , then is affine if and only if for all [7]. The significance of Neeman’s theorem is that it is not assumed that the ring is Noetherian. In [8], we show that if a quasiprojective variety is Stein, for all , and has algebraically independent nonconstant regular functions, then is an affine variety. In this note, we give a new criterion for affineness. Theorem 1. An irreducible quasiprojective variety of dimension is an affine variety if and only if for all , , and , where is any hypersurface with sufficiently large degree and . By Cartan’s Theorem B,
Graphical description of local Gaussian operations for continuous-variable weighted graph states
Jing Zhang
Physics , 2008, DOI: 10.1103/PhysRevA.78.052307
Abstract: The form of a local Clifford (LC, also called local Gaussian (LG)) operation for the continuous-variable (CV) weighted graph states is presented in this paper, which is the counterpart of the LC operation of local complementation for qubit graph states. The novel property of the CV weighted graph states is shown, which can be expressed by the stabilizer formalism. It is distinctively different from the qubit weighted graph states, which can not be expressed by the stabilizer formalism. The corresponding graph rule, stated in purely graph theoretical terms, is described, which completely characterizes the evolution of CV weighted graph states under this LC operation. This LC operation may be applied repeatedly on a CV weighted graph state, which can generate the infinite LC equivalent graph states of this graph state. This work is an important step to characterize the LC equivalence class of CV weighted graph states.
Page 1 /118965
Display every page Item

Copyright © 2008-2017 Open Access Library. All rights reserved.