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multi-field coupled color-changing devices and structures

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Science China(Technological Sciences) 2019年第6期62卷 1065-1066页

作者： BAO YinHua HAN Yu SONG WeiLi CHEN HaoSen FANG DaiNing State Key Laboratory for Turbulence and Complex System College of Engineering Peking University Beijing 100871 China Institute of Advanced Structure Technology Beijing Institute of Technology Beijing 100081 China

multi-field coupling phenomenon plays a significant role in the design and fabrication of color-changing devices. By introducing external fields, such as strain/stress, electric, thermal, or chemical fields, these dev... 详细信息

关键词： multi-field plays a significant optical tunability

Dose Comparison between Eclipse Dose Calculation and Fast Dose Calculator in Single- and multi-field Optimization Intensity-Modulated Proton Therapy Plans with Various multi-Beams for Brain Cancer

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International Journal of Medical Physics, Clinical Engineering and Radiation Oncology 2017年第4期6卷 421-432页

作者： Ryosuke Kohno Wenhua Cao Pablo Yepes Xuemin Bai Falk Poenisch David R. Grosshans Tetsuo Akimoto Radhe Mohan Department of Radiation Physics The University of Texas MD Anderson Cancer Center Houston TX USA Division of Radiation Oncology and Particle Therapy Exploratory Oncology Research & Clinical Trial Center National Cancer Center Hospital East Kashiwa Japan Department of Radiation Oncology The University of Texas MD Anderson Cancer Center Houston TX USA

The purpose of this study was to grasp current potential problems of dose error in intensity-modulated proton therapy (IMPT) plans. We were interested in dose differences of the Varian Eclipse treatment planning system (TPS) and the fast dose calculation method (FDC) for single-field optimization (SFO) and multi-field optimization (MFO) IMPT plans. In addition, because some authors have reported dosimetric benefit of a proton arc therapy with ultimate multi-fields in recent years, we wanted to evaluate how the number of fields and beam angles affect the differences for IMPT plans. Therefore, for one brain cancer patient with a large heterogeneity, SFO and MFO IMPT plans with various multi-angle beams were planned by the TPS. Dose distributions for each IMPT plan were calculated by both the TPS’s conventional pencil beam algorithm and the FDC. The dosimetric parameters were compared between the two algorithms. The TPS overestimated 400 - 500 cGy (RBE) for minimum dose to the CTV relative to the dose calculated by the FDC. These differences indicate clinically relevant effect on clinical results. In addition, we observed that the maximum difference in dose calculated between the TPS and the FDC was about 900 cGy (RBE) for the right optic nerve, and this quantity also has a possibility to have a clinical effect. The major difference was not seen in calculations for SFO IMPT planning and those for MFO IMPT planning. Differences between the TPS and the FDC in SFO and MFO IMPT plans depend strongly on beam arrangement and the presence of a heterogeneous body. We advocate use of a Monte Carlo method in proton treatment planning to deliver the most precise proton dose in IMPT.

关键词： Fast Dose Calculator Monte Carlo Intensity-Modulated Proton Therapy Single-field Optimization (SFO) multi-field Optimization (MFO)

The Description of Oil Displacement Mechanism in Steam Injection of multi-field Synergy with Exergy Transfer

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World Journal of Mechanics 2013年第3期3卷 169-173页

作者： Qinglin Cheng Yang Wang Xiaoli Sun Key Lab of Ministry of Education for Enhancing the Oil and Gas Recovery Ratio Northeast Petroleum University Daqing China

Steam injection is a most effective way for improving heavy oil recovery efficiency, and it has academic and practical significance for the mechanism of multi-field synergy oil displacement. Mechanism of “diversified” oil displacement which is obtained by traditional study methods in the exploitation territory of oil and gas fields has both respective roles and mutual cross shortages. To describe and analyze the displacement process of multi-field coupling with exergy transfer can simplify this kind of problem by introducing a unified goal-driving exergy. It needs to use the method of theoretical modeling, numerical simulation and experimental validation to study the basic law of exergy transfer in the oil displacement process of multi-field synergy, make a thorough research for the flooding process of steam injection with exergy transfer theory and reveal the oil displacement mechanism in steam injection of multi-field synergy. Thus the theory instruction and technical support can be provided to improve reservoirs producing degree and extraction ratio.

关键词： Steam Injection Exergy Exergy Transfer multi-field Synergy Mechanism of Oil Displacement

Review of pantograph and catenary interaction

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Frontiers of Mechanical Engineering 2018年第2期13卷 311-322页

作者： Weihua ZHANG Dong ZOU Mengying TAN Ning ZHOU Ruiping LI Guiming MEI State Key Laboratory of Traction Power Southwest Jiao Tong University Chengdu 610031 China

The application of electrified railway directly promotes relevant studies on pantograph-catenary interac- tion. With the increase of train running speed, the operating conditions for pantograph and catenary have become increasingly complex. This paper reviews the related achievements contributed by groups and institutions around the world. This article specifically focuses on three aspects： The dynamic characteristics of the panto- graph and catenary components, the systems＇ dynamic properties, and the environmental influences on the pantograph-catenary interaction. In accordance with the existing studies, future research may prioritize the task of identifying the mechanism of contact force variation. This kind of study can be carried out by simplifying the pantograph-catenary interaction into a moving load problem and utilizing the theory of matching mechanical impedance. In addition, developing a computational platform that accommodates environmental interferences and multi-field coupling effects is necessary in order to further explore applications based on fundamental studies.

关键词： electrified railway pantograph and catenary interaction contact force variation moving load problem mechanical impedance multi-field

Porosity and permeability variations of a dam curtain during dissolution

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Water Science and Engineering 2019年第2期12卷 155-161页

作者： Ji-xiang Huo Fu-heng Ma Xiao-lei Ji State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Nanjing Hydraulic Research InstituteNanjing 210029China College of Construction Engineering Jiangsu Open UniversityNanjing 210019China

During reservoir operation,the erosion effects of groundwater change the porosity and permeability of the dam curtain,causing changes to the seepage field.To understand where the changes take place and to what degree the porosity and permeability change,a multi-field coupling model was built and solved.The model takes into account seepage,solution concentration,and solid structure.The model was validated using uplift pressure monitoring data.Then,the variations in curtain porosity,seepage flow,and loss quantity of Ca(OH)2 were calculated.The key time nodes were obtained through curve fitting of the variation of seepage flow with the BiDoseResp function.The results showed that the model could reflect the attenuation trend of curtain performance well.The process and position of the erosion were not homogeneous.Although erosion mainly occurred at the top and bottom of the curtain,it was most developed at the top.The erosion effects developed slowly during the early stage,much fast during the middle and late stages,and culminated in complete dissolution.The model results and the daily monitoring data can provide a scientific basis for the safe operation and management of reservoirs.

关键词： Dam curtain Permeability multi-field coupling model Porosity Erosion Solute transport Seepage flow

瞿秋白与葛兰西：文艺意识形态人民观共振性分析

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