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Zhang Y.-Z.,Nanjing University of Posts and Telecommunications | Zhang Y.-Z.,Nanjing University | Zhang Y.-Z.,Beijing University of Posts and Telecommunications | Wu Z.-Q.,China R and nter | And 5 more authors.
Jisuanji Xuebao/Chinese Journal of Computers | Year: 2010

Program slicing is a family of program decomposition techniques. By introducing point-to analysis to the previous monadic slicing, the authors present and implement an approach of monadic slicing for a program with pointers. This approach obtains the point-to information through the data-flow iteration. Being different from the traditional methods, the point-to information and slicing are computed in the same phase in the method, by combining the forward monad slicing with data-flow iteration. Instead of recording point-to information for every statement, it is only needed to record the information for current analysis statements. So the method saves space without losing the precision. In addition, the approach also reserve the excellent properties of compositionality and language-flexibility from the original monadic slicing method.

He L.,Australian National University | Liu S.,Clinical Research | Shan C.,National Institutes for Food and Drug Control | Tu Y.,Clinical Research | And 2 more authors.
BMC Pharmacology and Toxicology | Year: 2016

Background: It has been observed that the efficacy of dipeptidyl peptidase-4 (DPP-4) inhibitors as compared to the placebo groups in some clinical trials conducted in China is weaker than that in trials conducted outside China, leading to the suspicion that this may be caused by differential Glycosylated Hemoglobin (HbA1c) response in the placebo arm of DPP-4 inhibitor clinical trials conducted in China compared to other countries. Methods: We searched published articles and other documents related to phase III placebo-control trials of DPP-4 inhibitors in Type 2 diabetes mellitus (T2DM). We included studies from different countries and compared those conducted in China to those conducted in other countries. Meta-regression analysis was used to analyze the HbA1c response in the placebo arms. Results: A total of 66 studies met the inclusion criteria and 10 were conducted within China. There were a total of 8303 participants (mean age 56, male 57 %) in placebo groups. The pooled change in HbA1c for the placebo groups of 10 trials conducted in patients with T2DM in China was 0.26 % (95 % CI [-0.36 %, -0.16 %], p-value < 0.001), compared to 0.015 % (95 % CI [-0.05 %, 0.08 %], p-value is 0.637) for 56 trials conducted outside of China. The difference of placebo effect between trials conducted in and outside China is -0.273 % (95 % CI [-0.42 %, -0.13 %], p-value is less than 0.001) while after excluding trials conducted in Japan, the difference is -0.203 % (95 % CI [-0.35 %, -0.06 %], p-value is 0.005). They are both statistically significant. Conclusions: The meta-analysis in the article demonstrates that there is statistically significant difference in the HbA1c response in the placebo arm of DPP-4 inhibitor clinical trials conducted in China compared to other countries. This differential HbA1c response in the placebo arm should be taken into consideration by both experimenters and medical decision makers when future DPP-4 studies are conducted in China. © 2016 The Author(s).

Shi Y.-L.,Tongji University | Yang L.,China R and nter | Zhang C.-L.,Shanghai JiaoTong University
Energy and Buildings | Year: 2011

The small air cooled chillers that serve an apartment building or residential villa often have the outdoor condensing units installed within a confined space. The installation distance between chiller and wall or between two chillers has significant impact on the chiller performance. In this study, three CFD (Computational Fluid Dynamics) approaches to condensing unit air management modeling are proposed and compared with each other first. The predicted air flow rates are compared to the test data as well. The comparison shows that the CFD approach with fan boundary definition is the most cost-effective, easy to be implemented, and accurate. Together with the chiller system modeling, a parametric study is further conducted to investigate the effect of the wall-chiller distance and the chiller-chiller distance on the chiller performance. © 2011 Elsevier B.V. All rights reserved.

Li H.,Tsinghua University | Moullec Y.L.,Électricité de France | Lu J.,China R and nter | Chen J.,Tsinghua University | And 2 more authors.
International Journal of Greenhouse Gas Control | Year: 2014

Solvent is a critical part of the post-combustion CO2 capture process by chemical absorption. Processes using good solvents will have low regeneration duty, high absorption rate, high cyclic capacity, and good resistance to degradation. This study focuses on the screening of cyclic amines (single or blended) of piperazine (PZ) derivatives based on the detailed VLE experiments for CO2 solubility, and analysis through simplified process modelling. With the proposed methodology, a new solvent can be efficiently compared with others in terms of operational cyclic capacity and regeneration duty. The study results showed that the most promising solvent candidate in terms of projected reboiler duty with a value of 2.5MJ/kg is the mixture of 1-MPZ and PZ. Considering the impact of cyclic capacity on the overall cost of the process and the unavoidable uncertainties of the screening procedure, three other solvents can be seen as promising: 1-MPZ, TEDA+PZ and DMPZ+PZ. © 2014 Elsevier Ltd.

Li H.,Tsinghua University | Le Moullec Y.,Électricité de France | Lu J.,China R and nter | Chen J.,Tsinghua University | And 3 more authors.
Fluid Phase Equilibria | Year: 2015

An accurate thermodynamic model is the primary element needed for the process simulation and optimization for CO2 absorption in aqueous amine solutions. In this work, the thermodynamic model was built in Aspen Plus, using the electrolyte nonrandom two-liquid (ENRTL) activity coefficient model to represent vapor pressure and heat capacity data, simultaneously, for amine, vapor-liquid equilibrium (VLE), excess enthalpy (HE), and pKa data for amine/H2O, and CO2 solubility data for amine/CO2/H2O. The cyclic diamine 1-methylpiperazine (1MPZ) is a promising amine for CO2 capture. CO2 solubility was measured for 1MPZ aqueous solutions at three concentrations - 10wt%, 30wt%, and 40wt% and four temperatures - 313.15K, 343.15K, 373.15K, and 393.15K. The excess enthalpy for 1MPZ+H2O was obtained by the Setaram C80 calorimeter at 303.15K and 323.15K, within a whole mole-fraction range. The interaction parameters of nonrandom two-liquid model (NRTL) and ENRTL, along with the standard state properties of amine ions - protonated 1MPZ (1MPZH+, 1MPZH2+), 1MPZ carbamate (1MPZCOO-), and protonated 1MPZ carbamate (H1MPZCOO) - were regressed from data obtained from this work as well as literature, which agreed with the model calculation. © 2015.

Tong C.,Tsinghua University | Perez C.C.,Tsinghua University | Chen J.,Tsinghua University | Marcos J.-C.V.,China R and nter | And 2 more authors.
Energy Procedia | Year: 2013

Absorbing CO2 with amine solutions is one of the most promising methods of CCS and has been widely applied. In order to improve efficiency and reduce costs, new solvents need to be selected. In this work, two amine solvents, N,N-dimethylethanolamine(DMEA) and Triethylene diamine (TEDA), have been characterized, with the use of gasliquid reactor for CO2 solubility and kinetic rate measurements. Solubility of CO2 has been measured for amine concentrations of 1.0, 2.5 and 4.0 mol/L at temperatures of 313.2K, 343.2K, 373.2K, and 393.2K while partial pressure of CO2 varies from 1 to 300kPa. The e-NRTL model has been used for these amine-water-CO2 systems in order to calculate CO2 solubility. Meanwhile the thermo-regulated constant interfacial area Lewis-type cell was also operated to obtain absorption kinetic data for CO2 absorption in 0.5M and 1.0M amine solutions.

Zhang Q.,CAS Institute of Electrical Engineering | Li X.,CAS Institute of Electrical Engineering | Wang Z.,CAS Institute of Electrical Engineering | Zhang J.,China R and nter | And 2 more authors.
Energy | Year: 2015

Molten salt receivers play an important role in converting solar energy to thermal energy in concentrating solar power plants. This paper describes a dynamic mathematical model of the molten salt cavity receiver that couples the conduction, convection and radiation heat transfer processes in the receiver. The temperature dependence of the material properties is also considered. The radiosity method is used to calculate the radiation heat transfer inside the cavity. The outlet temperature of the receiver is calculated for 11 sets of transient working conditions. The simulation results compare well with experimental data, thus the model can be further used in system simulations of entire power plants. © 2015 Elsevier Ltd. All rights reserved.

Zhang J.B.,China R and nter | Valle-Marcos J.C.,China R and nter | El-Hefni B.,Électricité de France | Wang Z.F.,CAS Institute of Electrical Engineering | And 4 more authors.
Energy Procedia | Year: 2013

This paper presents a first vertion of a dynamic model of the 1 MWe Central Receiver System demo plant at Badaling in Beijing with the purpose of improving the performance and reliability of the CSP technology deployed at this plant using dynamic modelling by Dymola® software in the frame of cooperation between EDF R&D and IEECAS (Institute of Electrical Engineering of the Chinese Academy of Sciences). This dynamic model is capable of simulating the dynamic behavior of the entire CSP plant, covering the heliostat field, the superheated steam cavity receiver, the thermal storage system and the power block. In order to validate the model, the demo plant operation data is used. The recorded evolution of the different process parameters during the operation is compared to the results predicted by the dynamic model. According to the results obtained from the operation, the simulation predicts fairly well the main process parameters. The predicted trend of the dynamic behavior of the system is also satisfactory. The results show that the model could be used to support the operation of the entire solar thermal power tower system and help improve the performance of the CSP technology deployed at Badaling. © 2013 The Authors.

Xiang Q.,Zhejiang University | Moullec Y.L.,Électricité de France | Fang M.,Zhejiang University | Valle-Marcos J.-C.,China R and nter | And 5 more authors.
Energy Procedia | Year: 2014

High energy consumption during solvent regeneration is a crucial issue for the CO2 post-combustion capture by chemical absorption. In order to save the latent heat in the regeneration process, it is possible to regenerate the solvent through direct steam stripping. This work aims to validate the direct steam stripping process by experimental study on a lab-scale stripper column. The novel direct steam stripping process showed potential to reduce regeneration energy in comparison to the conventional regeneration process. The minimum energy consumption of direct steam stripping mode was 2.98 MJ/kg CO2, 23% lower than that of the conventional regeneration mode which is 3.88 MJ/kg CO2. Water balance was also investigated. Based on the experimental results, a high feeding solvent temperature close to solvent boiling point and superheated carrier steam was preferred for direct steam stripping process. © 2014 The Authors Published by Elsevier Ltd.

Faille D.,Électricité de France | Liu S.,China R and nter | Wang Z.,Chinese Academy of Sciences | Yang Z.,Chinese Academy of Sciences
Energy Procedia | Year: 2013

This paper deals with the development of a control design model for a 1MW Solar Tower equipped with a heat storage facility. This model is precise enough to achieve a good prediction of the responses but is also simple enough to avoid computational burden. The paper presents the assumptions and equations used for the different components of the plant. The behavior of the model developed in Matlab/Simulink™ is qualitatively validated by closed loop simulations. The control used for these simulations is also given. It consists of two levels, the upper level being an automaton whose outputs are the set points of the lower level controllers. © 2013 D. Faille.

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