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Design of a Developing Platform of Supervisor and Management System for Industrial Process in DCS Based on Client/Server Architecture

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Journal of Central South University 2000年第2期12卷 97-99页

作者： Chen song-qiao Su Hong College of Information Science and Engineering Central South University of TechnologyChangsha 410083China

Build a general software development platform for industrial process supervisor and management system by combining the technology of industrial configuration and Client/Server model, and introduce the architecture and topological application of this platform. It puts forward a solution to the real time problem in the industrial distributed supervisor system.

关键词： distributed control system client/server architecture industrial configuration

Empirical Likelihood Based Goodness-of-fit Testing for Generalized Linear Mixed Models

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Acta Mathematicae Applicatae Sinica 2014年第1期30卷 37-48页

作者： song-qiao WEN Li-xing ZHU College of Mathematics and Computational Science Shenzhen University School of Statistics Renmin University of China

In this paper, we propose a bias-corrected empirical likelihood （BCEL） ratio to construct a goodness- of-fit test for generalized linear mixed models. BCEL test maintains the advantage of empirical likelihood that is self scale invariant and then does not involve estimating limiting variance of the test statistic to avoid deteri- orating power of test. Furthermore, the bias correction makes the limit to be a process in which every variable is standard chi-squared. This simple structure of the process enables us to construct a Monte Carlo test proce- dure to approximate the null distribution. Thus, it overcomes a problem we encounter when classical empirical likelihood test is used, as it is asymptotically a functional of Gaussian process plus a normal shift function. The complicated covariance function makes it difficult to employ any approximation for the null distribution. The test is omnibus and power study shows that the test can detect local alternatives approaching the null at parametric rate. Simulations are carried out for illustration and for a comparison with existing method.

关键词： Empirical likelihood bias correction monte carlo test generalized linear mixed model

Adaptive service configuration approach for quality of service management in ubiquitous computing environments

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第7期10卷 964-975页

作者： Yong ZHANG Shen-sheng ZHANG song-qiao HAN Department of Computer Science and Engineering Shanghai Jiao Tong University Shanghai 200240 China

Mobility and resource-limitedness pose challenging issues to service configuration for quality of service (QoS) management in ubiquitous computing environments. Previous configuration approaches, such as static resource reservation, dynamic resource allocation and single service composition are not valid in the environments. In this study, we present an adaptive service configuration approach. Firstly, we reduce the dynamic configuration process to a control model which aims to achieve the variation of critical QoS on minimal level with less resource cost. Secondly, to deal with different QoS variations, we design two configuration strategies—service chain reconfiguration and QoS parameter adjustment—and implement them based on fuzzy logic control theory. Finally, a configuration algorithm is developed to flexibly employ the two configuration strategies in tune with the error of critical QoS in configuration process. The results of simulation experiments suggest that our approach outper- forms existing configuration approaches in both QoS improvement and resource utilization.

关键词： Service configuration Ubiquitous computing (UbiComp) Quality of service (QoS) Fuzzy logic control

Quantum non-demolition phonon counter with a hybrid optomechnical system

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Science China(Physics,Mechanics & Astronomy) 2018年第5期61卷 1-9页

作者： qiao song KeYe Zhang Ying Dong WeiPing Zhang Quantum Institute for Light and Atoms School of Physics and Material Science East China Normal University Shanghai 200241 China Institute for Quantum Computing and Department of Physics and Astronomy University of Waterloo Waterloo Ontario N2L 3G1 Canada Department of Physics and Astronomy Shanghai Jiao Tong University and Tsung-Dao Lee Institute Shanghai 200240 China Collaborative Innovation Center of Extreme Optics Shanxi University Taiyuan 030006 China

A phonon counting scheme based on the control of polaritons in an optomechanical system is proposed. This approach permits us to measure the number of phonons in a quantum non-demolition(QND) manner for arbitrary modes not limited by the frequency matching condition as in usual photon-phonon scattering detections. The performance on phonon number transfer and quantum state transfer of the counter are analyzed and simulated numerically by taking into account all relevant sources of noise.

关键词： phonon counting optomechanics quantum non-demolition quantum hybrid system

Ringing cancellation in Carr-Purcell-Meiboom-Gill-type sequences

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Magnetic Resonance Letters 2022年第4期2卷 233-242页

作者： Shin Utsuzawa Marcus Donaldson Yi-qiao song Schlumberger-Doll Research CambridgeMA02139USA John A.Paulson School of Engineering and Applied Sciences Harvard UniversityCambridgeMA02138USA Athinoula A.Martinos Center for Biomedical Imaging Department of RadiologyMassachusetts General HospitalCharlestownMA02129USA

We propose a four-step phase cycling scheme that can cancel ringings from both the excitation and the refocusing pulses in Carr-Purcell-Meiboom-Gill(CPMG)*** allows accurate measurements of the first echo with short echo spacing tE,yielding improved precision of porosity,permeability,and fluid type identification in porous media study,at a cost of~25%signal *** our example,we achieved tE=100 ms on a 6.8 MHz unilateral NMR sensor without using a *** methods can be integrated in all nuclear magnetic resonance(NMR)protocols using CPMG,such as relaxation(T1,T2)and diffusion measurements,and do not require additional hardware(e.g.,Qswitches)to cancel ringing(although it can be used with a Q-switch to further reduce residual ringing).

关键词： CPMG Ringing cancellation Phase cycling

Glutathione as the End Capper for Cyclodextrin/PEG Polyrotaxanes

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Chinese Journal of Polymer Science 2014年第8期32卷 1003-1009页

作者： qiao song Zhi Luo 童新明 Yi Du Yanbin Huang Department of Chemical Engineering Tsinghua University

A facile one-pot synthesis of α-cyclodextrin-based polyrotaxane （PR） in aqueous solution is reported, where the peptide glutathione was used as the end-capping agent and the thiol-ene Michael addition was used as the end-capping reaction. Both polyrotaxanes with low threading ratio and high threading ratio were successfully obtained. In contrast to the conventionally used multiple-step synthesis methods and hydrophobic end cappers, this one-pot aqueous synthesis as well as the biocompatibility of the end-capping agent could result in a much more biocompatible PR to be used as biomaterials.

关键词： Polyrotaxane Cyclodextrin Polyethylene glycol Glutathione Biocompatibility.

Fracture Analysis of Cast Iron Materials with Cracks Based on Elastoplastic Extended Finite Element Method

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Acta Mechanica Solida Sinica 2019年第2期32卷 201-214页

作者： Yanjun Chang qiao song Zheng Kuang Keshi Zhang Zhanguang Zheng College of Civil Engineering and Architecture Guangxi University Nanning 530004 China College of Mechanical Engineering Guangxi University Nanning 530004 China Guangxi Key Laboratory of Disaster Prevention and Engineering Safety Guangxi University Nanning 530004 China Key Laboratory of Engineering Disaster Prevention and Structural Safety of Ministry of Education Guangxi University Nanning 530004 China

Based on the ABAQUS platform for finite element analysis, the extended finite element method (XFEM) considering elastoplastic constitutive relationship is developed, by which the displacement discontinuity across the crack surface and the strong nonlinearity near the crack tip can be described more accurately. The strip specimens with unilateral cracks and central cracks under uniaxial tension are simulated using the XFEM and the FEM, respectively. The J-integral across the crack on each incremen t is calcula ted using the equivale nt domain integral met hod (EDIM), the interaction integral met hod and the FEM, respectively. The effec ts of mesh size and mesh shape near the crack tip, element type and different calculation methods on the accuracy of J-integral are analyzed. The simulation results show that the XFEM is more accurate than the FEM with the same element size and type. The fracture tests of cast iron specimens with unilateral cracks under uniaxial tension are performed, and the J-integral criterion is valid to predict the fracture initiation in numerical simulation. The critical value of J-integral is calculated using the EDIM of the XFEM. The comparisons demonstrate that the simulated elastoplastic load-displacement curves with the XFEM are in good agreement with the experimental results.

关键词： J-Integral Extended finite element Elastoplasticity Fracture criterion

Flares and magnetic non-potentiality of NOAA AR 11158

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Research in Astronomy and Astrophysics 2013年第2期13卷 226-238页

作者： qiao song Jun Zhang Shu-Hong Yang Yang Liu Key Laboratory of Solar Activity National Astronomical ObservatoriesChinese Academy of Sciences W.W.Hansen Experimental Physics Laboratory Stanford University

Magnetic non-potentiality is important for understanding flares and other solar activities in active regions （ARs）. Five non-potential parameters, i.e. electric current, current helicity, source field, photospheric free energy, and angular shear, are calculated to quantify the non-potentiality of NOAA AR 11158. Benefitting from the high spatial resolution, high cadence and continuous temporal coverage of vector mag- netograms from the Helioseismic and Magnetic Imager onboard the Solar Dynamics Observatory, both the long-term evolution of the AR and the rapid change during flares are studied. We confirm that, compared with the magnetic flux, the magnetic non-potentiality has a closer connection with the flare, and the emerging flux regions are important for understanding the magnetic non-potentiality and flares. The main re- suits are as follows. （1） The vortex in the source field directly displays the deflection of the horizontal magnetic field. The deflection corresponds to the fast rotating sunspot with a time delay, which suggests that the sunspot rotation leads to an increase in the non-potentiality. （2） Two areas that have evident changes in the azimuth of the vector magnetic field are found near the magnetic polarity inversion line. The change rates of the azimuth are about 1.3° h-1 and 3.6° h-1, respectively. （3） Rapid and prominent increases are found in the variation of helicity during four flares in the regions where their initial brightening occurs. The recovery of the increases takes 3-4 h for the two biggest flares （X2.2 and M6.6）, but only takes about 2 h for the two other smaller flares （M2.2 and M1.6）.

关键词： Sun activity -- Sun flares -- Sun magnetic fields -- Sun photosphere -- sunspots

Study on Polygon Region Filling Method

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Journal of Central South University 2000年第2期12卷 104-106页

作者： WANG Jia-yang CHEN song-qiao WANG Can-dong College of Information Science and Engineering Central South University of TechnologyChangsha 410083China

The paper puts forward a highly efficient and practical scan line based on the filling algorithm. The algorithm takes the lines of polygon as line segments with directions and introduces the concept of marked value when the apex of polygon faces scan line, determines whether there are intersection points between the lines of polygon and scan lines, by judging whether the marked value has changed or not. This method avoids the extra decision and treatment of odd points in traditional algorithm, and it needs little calculations but it is highly efficient.

关键词： computer graphics filling algorithm polygon