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IMPLEMENTATION OF MIXED METHODS AS FINITE DIFFERENCE METHODS AND APPLICATIONS TO NONISOTHERMAL MULTIPHASE FLOW IN PORouS MEDIA

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Journal of Computational Mathematics 2006年第3期24卷 281-294页

作者： Zhang-xin Chen Xi-jun yu Center for Scientific Computation Box 750156 Southern Methodist University Dallas TX 75275-0156 USA Research Center for Science Xi'an Jiaotong University Xi'an 710049 China Center for Advanced Reservoir Modeling and Simulation College Vof Engineering'PekingI University China Laboratory of Computational Physics Institute of Applied Physics and Computational Mathematics Beijing 100088 China

In this paper we consider mixed finite element methods for second order elliptic problems. In the case of the lowest order Brezzi-Douglas-Marini elements （if d = 2） or Brezzi- Douglas-Duran-Fortin elements （if d = 3） on rectangular parallelepipeds, we show that the mixed method system, by incorporating certain quadrature rules, can be written as a simple, cell-centered finite difference method. This leads to the solution of a sparse, positive semidefinite linear system for the scalar unknown. For a diagonal tensor coefficient, the sparsity pattern for the scalar unknown is a five point stencil if d = 2, and seven if d = 3. For a general tensor coefficient, it is a nine point stencil, and nineteen, respectively. Applications of the mixed method implementation as finite differences to nonisothermal multiphase, multicomponent flow in porous media are presented.

关键词： Finite difference Implementation Mixed method Error estimates Superconvergence Tensor coefficient Nonisothermal multiphase Multicomponent flow Porousmedia.

Two new benzophenone glucosides from Cratoxylon cochinchinensis

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Chinese Chemical Letters 2009年第4期20卷 459-461页

作者： Hai Yang yu San Lin Jin Xue.Zhang yuan Liu Yang Fu ou Nai Li Wang xin Sheng Yao College of Traditional Chinese Materia Medica Shenyang Pharmaceutical University Shenyang 110016 China Shenzhen Key Laboratory for New Drugs Research of Traditional Chinese Medicines Research Institute of Tsinghua University Shenzhen 518057 China

Two new benzophenone glucosides were isolated from the 60% ethanol extract of the dried stems of Cratoxylum cochinchinense. The structures were elucidated as 3-O-β-D-glucopyranosyl-2＇,4,6＇-trihydroxy-benzophenone a... 详细信息

关键词： Cratoxylum cochinchinense Benzophenone glucosides

Extraction of rare earth ions from phosphate leach solution using emulsion liquid membrane in concentrated nitric acid medium

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Journal of Rare Earths 2018年第11期36卷 1190-1197页

作者： Qianlin Chen xin Ma xin Zhang yunqi Liu Ming yu School of Chemistry and Chemical Engineering Cuizhou University Guiyang 550003 China Guizhou Engineering & Technology Research Center of Clean Production in Phosphorus Chemical Industry Guiyang 550003 China

It is very significant to recover rare earths （REs） from wet-process phosphoric acid, in terms of extraction rate and selectivity, the current carrier di（2-ethlhexly） phosphate （D2EHPA） out there is still inferior. Based on this question, our team modified D2EHPA to synthesize new extractants. This paper presents a comprehensive study on the extraction of rare earth ions （RE3＋） from phosphate leach solution using emulsion liquid membrane （ELM） in concentrated nitric acid medium. The ELM system is made up of （RO）2P（O）OPh-COOH as carrier, polyisocrotyl succinimide （T154） as surfactant, sulfonated kerosene as diluent, phosphoric acid （H3PO4） as stripping solution. Different chemical parameters such as type and concentration of carrier, surfactant, stripping solution, volume ratio of oil phase to internal phase, and volume ratio of emulsion ratio to external phase were analyzed. The extraction of RE^3＋ was evaluated by the yield of extraction. In addition, the demulsification process was also investigated. The proposed method of ELM using （RO）2P（O）OPh-COOH as carrier can he expected to provide an efficient, simplify operation, and facilitated method for extractine RE^3＋.

关键词： Emulsion liquid membrane Rare earth Nitric acid Extraction rate Phosphate rock Stripping solution

Semantic segmentation-assisted instance feature fusion for multi-level 3D part instance segmentation

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Computational Visual Media 2023年第4期9卷 699-715页

作者： Chun-yu Sun xin Tong Yang Liu Institute for Advanced Study Tsinghua UniversityBeijing 100084China Microsoft Research Asia Beijing 100080China

Recognizing 3D part instances from a 3D point cloud is crucial for 3D structure and scene *** learning-based approaches use semantic segmentation and instance center prediction as training tasks and fail to further exploit the inherent relationship between shape semantics and part *** this paper,we present a new method for 3D part instance *** method exploits semantic segmentation to fuse nonlocal instance features,such as center prediction,and further enhances the fusion scheme in a multi-and cross-level *** also propose a semantic region center prediction task to train and leverage the prediction results to improve the clustering of instance *** method outperforms existing methods with a large-margin improvement in the PartNet *** also demonstrate that our feature fusion scheme can be applied to other existing methods to improve their performance in indoor scene instance segmentation tasks.

关键词： 3D part instance segmentation feature fusion 3D deep learning

Stage Division and Pattern Discovery of Complex Patient Care Processes

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Journal of Systems Science & Complexity 2017年第5期30卷 1136-1159页

作者： WANG Tingyan TIAN xin yu Ming QI xin YANG Lan Health Care Services Research Center Department of Industrial EngineeringTsinghua UniversityBeijing 100084China Research Center on Fictitious Economy and Data Science Chinese Academy of SciencesBeijing 100190China School of Economics and Management University of Chinese Academy of SciencesBeijing 100190China Health Care Serv-ices Research Center Department of Industrial EngineeringTsinghua UniversityBeijing 100084China

This paper studies the design of a clinical pathway that defines medical service activities within each stage of a patient care process. Much prior research has developed clinicM process models that consider the trajectory of services occurring in a care process, by using data mining techniques on process execution logs. A novel approach that provides a more efficient way of clinical pathway design is introduced in this paper. Based on the strategy of TEI@I methodology, the proposed approach integrates statistical methods, optimization techniques and data mining. With the preprocessed data, a complex care process is subsequently divided into several medical stages, and then the patterns of each stage are identified, and thus a clinical pathway is developed. Finally, the proposed method is applied to the real world, using archival data derived from a hospital in Beijing, about three diseases that involve various departments, with an average of 300 samples for each disease. The results of real- world applications demonstrate that the proposed method can automatically and efficiently facilitate clinical pathways design. The main contributions to the field in this paper include （a） a new application of TEI@I methodology in healthcare domain, （b） a novel method for complex processes analysis, （c） tangible evidence of automatic clinical pathways design in the real world.

关键词： Clinical pathway frequent pattern mining stage division TEI@I virtual business.

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青稞分蘖角度的QTL定位

作物学报 2025年第1期51卷 260-272页

作者：杨景发余鑫莲姚有华姚晓华王蕾吴昆仑李新青海大学农林科学院/青海省作物分子育种重点实验室/青海省青稞遗传育种重点实验室/青藏高原种质资源研究与利用实验室/青海大学省部共建三江源生态与高原农牧业国家重点实验室青海西宁810016

分蘖角度是青稞株型的主要构成因素,在提高青稞产量与抗倒伏性中发挥着极为重要的作用。为解析青稞分蘖角度的遗传机制,本研究以青稞品种‘达章紫’(株型松散)和‘昆仑10号’(株型紧凑)为亲本构建的RIL群体为材料,基于高密度遗传图谱,... 详细信息

分蘖角度是青稞株型的主要构成因素,在提高青稞产量与抗倒伏性中发挥着极为重要的作用。为解析青稞分蘖角度的遗传机制,本研究以青稞品种‘达章紫’(株型松散)和‘昆仑10号’(株型紧凑)为亲本构建的RIL群体为材料,基于高密度遗传图谱,在多环境中进行青稞分蘖角度的QTL定位,并利用RIL群体衍生的剩余杂合系,对鉴定到的主效QTLqTA7H-1进行精细定位。在青稞7条染色体上共检测到9个控制分蘖角度的QTL,解释表型变异为6.41%~33.57%,其中,qTA3H-1和qTA7H-1为多环境共检测的主效QTL,平均加性效应分别为5.42°(增效)和-3.87°(减效);在减效QTL qTA7H-1初定位区间筛选到4个剩余杂合体,自交衍生F8:9近等基因系,在置信区间内加密设计14对分子标记对RHL群体极端单株进行检测,利用获得的5种交换类型单株,将qTA7H-1进一步界定在PC08(32,252,397)与PA10(41,790,765)约9.54Mb的物理区间内。本研究初步揭示调控青稞分蘖角度的遗传因子,为开展分蘖角度性状的遗传改良与分子设计育种奠定了基础。

关键词：青稞分蘖角度 QTL定位主效位点

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Synthesis and Spectroscopic Properties of Cyclotriphosphazenes Containing 6-(4-Hydroxyphenyl)-2,2'-bipyridine Side Groups

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Chemical Research in Chinese Universities 2007年第6期23卷 679-682页

作者： ZHANG Jun-feng GAN xin ou Xue-mei FU Wen-fu College of Chemistry and Chemical Engineering Yunnan Normal University Kunming 650092 P. R. China Technical Institute of Physics and Chemistry Chinese Academy of Sciences Beijing 100080 P. R. China

Two novel cyclotriphosphazene derivatives containing 6- （4-hydroxyphenyl）-2,2′-bipyridine （hopbp） side groups, N3 P3 （dobp） 2 （hopbp） 2 （ 1 ） and N3 P3 （dobp）（hopbp） 4 （2）（ dobp = 2,2′-dioxybiphenyl）, were synthesized and characterized. These compounds display strong fluorescent emission both in solution and in solid state. Their absorption and emission spectra are sensitive to proton： the addition of HBF4 to the methanol and dichloromethane solution（9： 1, volume ratio） of compound 1 led to a red-shift from 350 to 460 nm for the emission spectrum, and the process was also characterized by isosbestic points of absorption spectra at 267, 287 and 313 nm.

关键词： Cyelotriphosphazene Bipyridine Proton Spectra

Conservative and functional surgery in the treatment of salivary gland tumours

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International Journal of Oral Science 2019年第3期11卷 176-179页

作者： Guangyan yu xin Peng Department of Oral & Maxillofacial Surgery Peking University School and Hospital of Stomatology

The principle of modern oncological surgery is to conserve the functional organs or tissues as much as possible based on eradication of the *** salivary gland tumours,conservative and functional salivary surgery,including partial sialoadenectomy as well as anatomical and functional preservation of the facial nerve,great auricular nerve,superficial musculoaponeurotic system (SMAS),and Stensen’s duct,has become increasingly *** the present review,we discuss the following aspects of conservative and functional surgery in the treatment of salivary gland tumours:(i) partial superficial parotidectomy (PP) to treat benign parotid gland tumours,(ii) modification of surgical incisions to improve cosmetic results,(iii) modification of the surgical approach to decrease complications,(iv) extracardial dissection to treat benign superficial parotid tumours,(v) partial sialoadenectomy to treat benign submandibular gland tumours,and (vi) 125I brachytherapy to preserve facial *** majority of the operated parotid or submandibular glands are preserved,and surgical complications are also *** and functional surgery plays a significant role in maintaining normal salivary gland function and in improving patients’ quality of life during the treatment of salivary gland tumours and thus should be further promoted.

关键词： salivary gland great auricular nerve parotid gland

Microstructure evolution and liquid phase separation in Ta-O hypermonotectic melts during laser-cladding

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China Foundry 2018年第3期15卷 222-227页

作者： Hai-ou Yang Meng Wang xin Lin Wei-dong Huang State Key Laboratory of Solidification Processing Northwestern Polvtechnical University Xi'an Shaanxi 710072 PR China MHT Key Laboratory of Metal High Performance Additive Manufacturing and Innovative Design Northwestern Polytechnical University Xi'an Shaanxi 710072 PR China

A three-layer Ta_2O_5-containing coating was successfully fabricated by laser cladding on a pure Ta substrate. The maximum thickness of such a coating is about 1.6 mm. The microstructure, phase constitution and elemental distribution in the coating were investigated. Results show that the coating has been metallurgically bonded to the Ta substrate and the microstructure exhibits a graded change along the deposition direction from Ta substrate to the top of coating. In the layers I and II of the graded coating, the microstructure evolution can be confi rmed as a result of hypomonotectic reaction, but in the layer Ⅲ it was formed by hypermonotectic reaction. At the top of coating, the microstructure was still homogeneous although liquid phase separation had occurred, which can be attributed to the fact that the O-rich droplets do not have enough time to fl oat at high cooling rate. The theoretical calculation results show that during laser cladding, the solidifi cation time of the melt pool was less than 0.1 s, which fi ts well with the results from the experiment.

关键词： Laser cladding liquid phase separation microstructure evolution homogeneous structure