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POINCARE-LIGHTHILL-KUO METHOD AND SYMBOLIC COMPUTATION

Applied Mathematics and Mechanics(English Edition) 2001年第3期22卷 261-269页

作者： DAI shi-qiang(戴世强) Shanghai Institute of Applied Mathematics and Mechanics Shanghai University Shanghai 200072 P R China

This paper elucidates the effectiveness of combining the Poincare-Lighthill-Kuo method (PLK method, for short) and symbolic computation. Firstly, the idea and history of the PLK method are briefly introduced. Then, the difficulty of intermediate expression swell, often encountered in symbolic computation, is outlined. For overcoming the difficulty, a semi-inverse algorithm was proposed by the author, with which the lengthy ports of intermediate expressions are first frozen in the form of symbols till the Fnal stage of seeking perturbation solutions. Tn discuss the applications of the above algorithm, the related work of the author and his research group on nonlinear oscillations and waves is concisely reviewed. The computer-extended perturbation solution of the Duffing equation shows that the asymptotic solution obtained with the PLK method possesses the convergence radius of 1 and thus the range of validity of the solution is considerably enlarged. The studies on internal solitary waves in stratified fluid and on the head-on collision between two solitary waves in a hyperelastic rod indicate that by means of the presented methods, very complicated manipulation, unconceivable in hand calculation, can be conducted and thus result in higher-order evolution equations and asymptotic solutions. The examples illustrate that the algorithm helps to realize the symbolic computation on micro-commputers. Finally, it is concluded that,vith the aid of symbolic computation, the vitality of the PLK method is greatly. Strengthened and at least for the solutions to conservative systems of oscillations and waves, it is a powerful tool.

关键词： PLK method perturbation methods symbolic computation intermediate expression swell semi-inverse algorithm

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Discrete decision model and multi-agent simulation of the Liang Zong two-chain hierarchical organization in a complex project

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Journal of Systems Engineering and Electronics 2018年第2期29卷 311-320页

作者： MAI qiang ZHAO Yueqiang AN shi School of Management Harbin Institute of Technology Defense Technology Academy China Aerospace Science & Industry Corporation

Different from the organization structure of complex projects in Western countries, the Liang Zong hierarchical organization structure of complex projects in China has two different chains, the chief-engineer chain and the general-director chain,to handle the trade-off between technical and management decisions. However, previous works on organization search have mainly focused on the single-chain hierarchical organization in which all decisions are regarded as homogeneous. The heterogeneity and the interdependency between technical decisions and management decisions have been neglected. A two-chain hierarchical organization structure mapped from a real complex project is constructed. Then, a discrete decision model for a Liang Zong two-chain hierarchical organization in an NK model framework is proposed. This model proves that this kind of organization structure can reduce the search space by a large amount and that the search process should reach a final stable state more quickly. For a more complicated decision mechanism, a multi-agent simulation based on the above NK model is used to explore the effect of the two-chain organization structure on the speed, stability, and performance of the search process. The results provide three insights into how, compared with the single-chain hierarchical organization, the two-chain organization can improve the search process: it can reduce the number of iterations efficiently; the search is more stable because the search space is a smoother hill-like fitness landscape; in general, the search performance can be ***, when the organization structure is very complicated, the performance of a two-chain organization is inferior to that of a single-chain organization. These findings about the efficiency of the unique Chinese-style organization structure can be used to guide organization design for complex projects.

关键词： complex project two-chain hierarchical organization discrete decision model multi-agent simulation

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Evaluation of teaching-in-English reform in five-year clinical tropical medicine program–Case analysis of curriculum reform of clinical medicine in Hainan Medical University

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Asian Pacific Journal of Tropical Biomedicine 2017年第12期7卷 1125-1128页

作者： shi-Jiao Yan yun-qiang Chen Jiao Chen Chuan-Zhu Lv Hainan Medical University Haikou 571199HainanChina

Objective: To investigate the model, quality as well as effect of teaching-in-English in five-year clinical medicine program of Hainan Medical ***: The questionnaire was carried out among clinical medicine undergraduates of2012–2015 grades in Hainan Medical University, to investigate studying time, studying habits and the impact of teaching in English. Additionally results of CET-4, CET-6 and overseas internship from undergraduates of 2012–2015 grade, as well as the result of phased medical licensing examination and post-graduate entrance examination from undergraduates of 2012 were accordingly collected from the Teaching Management ***: For the Chinese students in international classes, the average time of self-study was 161.49 min, 58.3% had preview before classes, and 90.7% had habit of review after classes. Thus the first time pass rate, total pass rate, first time excellent rate and total excellent rate of CET-4 and CET-6 of international classes were significantly higher than those of regular classes. The result of post-graduate entrance examination in 2016 showed that the score, pass rate and acceptance rate of international classes of 2012 grade were significantly higher those of regular classes(P < 0.01).Conclusions: Teaching-in-English reform in Hainan Medical University has achieved initial success. Chinese students from international classes are superior to those from regular classes in many aspects. However, there are still many problems, and effective measures should be implemented to promote teaching quality continuously.

关键词： Five-year clinical medicine program Teaching-in-English Teaching reform Effect

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Reagent elution combined with positive pressure filtration:A zero-discharge method for cyanide tailings remediation

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Journal of Environmental Sciences 2022年第3期34卷 376-384页

作者： qiang Liu Yating Luo Jiyan shi Department of Environmental Engineering College of Environmental and Resource ScienceZhejiang UniversityHangzhou 310058China Changchun Gold Research Institute Co.Ltd Changchun 130012China

At present, the cyanide gold extraction process is still the main technology for gold production. Generated cyanide tailings containing highly toxic substances exhibit potential environmental risks. These tailings are in urgent need of purification treatment, especially after being classified as hazardous waste. In this study, the impacts of elution methods, operating time, tailings/water ratios, reagent types on the elution rates of cyanide were investigated. Furthermore, the composite elution method developed in this research was extended for engineering. Results showed that the optimum elution conditions were determined to be: stirring elution, tailings/water ratio( M/V;1:1) and operating time(10-20 min). Besides, 4 reagents(sodium dodecyl benzene sulfonate, cyclodextrin, sodium silicate and calcium hydroxide) were selected from four categories of 21 reagents for further composite elution. The cyanide elution rate was the highest(90.7% ±0.1%) while the molar ratio of these 4 reagents was 5:2:2:1. Moreover, the combination of reagent elution and positive pressure filtration improved the elution efficiency of cyanide(92.6% ±0.8%). And the cyanide content in the toxic leaching solution was lower than the standard value(5.0 mg/L). Furthermore, the composite elution method developed in this study was also extended for engineering. The concentration of cyanide in the leachate was < 5.0 mg/L, and was stable during 189 days of detection. Notably, the effluent can be reused directly, or reused after further treatment. The zero discharge of effluents and solid wastes was realized in the processes. The above results provided supports for the engineering treatment of cyanide tailings.

关键词： Cyanide tailings Decyanation treatment Remediation Engineering

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A 3D Geometry Model of Vocal Tract Based on Smart Internet of Things

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Computer Systems Science & Engineering 2023年第7期46卷 783-798页

作者： Ming Li Kuntharrgyal Khysru Haiqiang shi qiang Fang Jinrong Hu yun Chen Tianjin Medical University General Hospital Tianjin300041China Key Laboratory of Artificial Intelligence Application Technology State Ethnic Affairs Commission Qinghai Minzu UniversityXining810007China Chinese Academy of Sciences Beijing300308China School of Computer Science Chengdu University of Information and TechnologyChengduSichuan610225China College of Intelligence and Computing Tianjin UniversityTianjin300350China

The Internet of Things(IoT)plays an essential role in the current and future generations of information,network,and communication development and *** research focuses on vocal tract visualization and modeling,which are critical issues in realizing inner vocal tract *** is applied in many fields,such as speech training,speech therapy,speech analysis and other speech production-related *** work constructed a geometric model by observation of Magnetic Resonance Imaging data,providing a new method to annotate and construct 3D vocal tract *** proposed method has two advantages compared with previous *** it has a uniform construction protocol for all speech ***,this method can build correspondent feature points between different speech *** are less than three control parameters can be used to describe every speech organ accurately,for which the accumulated contribution rate is more than 88%.By means of the reconfiguration,the model error is less than 1.0 *** to the data from Chinese Magnetic resonance imaging(MRI),this is the first work of 3D vocal tract *** will promote the theoretical research and development of the intelligent Internet of Things facing speech generation-related issues.

关键词： Virtual reality vocal tract visualization articulatory modeling IoT

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Intravascular papillary endothelial hyperplasia as a rare cause of cervicothoracic spinal cord compression:A case report

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World Journal of Clinical Cases 2021年第34期9卷 10681-10688页

作者： Hong-Lin Gu Xiao-Qing Zheng shi-qiang Zhan yun-Bing Chang Department of Spine Surgery Guangdong Provincial People’s HospitalGuangdong Academy of Medical SciencesGuangzhou 510080Guangdong ProvinceChina

BACKGROUND Intravascular papillary endothelial hyperplasia(IPEH)is a rare benign reactive vascular lesion that grows into an expansile compressing *** most commonly involves the skin and subcutaneous *** involvement is rare,with only 11 reported cases in the *** report,to our knowledge,the first case of IPEH in the cervicothoracic spinal canal and present a literature *** SUMMARY A 27-year-old man presented with acute-onset neck pain,numbness,and weakness in his *** resonance imaging showed an epidural mass in the cervicothoracic(C6-T1)spinal canal and vertebral hemangioma(VH)involving the C7 vertebral body.C6-T1 Laminectomy and radical excision of the mass were *** examinations revealed papillary proliferation of vascular endothelial cells with thrombus formation,and an IPEH diagnosis was *** his 6-mo follow-up appointment,his symptoms were relieved without *** possible pathogenesis,clinical and imaging features,differential diagnosis,and management of IPEH were *** We report,to our knowledge,the first case of IPEH in the cervicothoracic spinal canal,treated via complete resection,and showing a favorable *** found a causal relationship between spinal IPEH and VH;this partly explains the mechanism of IPEH.

关键词： Intravascular papillary endothelial hyperplasia Cervicothoracic Spinal cord compression Thrombosis Hemangioma Case report

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A Nonlocal Stokes Systemwith Volume Constraints

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Numerical Mathematics(Theory,Methods and Applications) 2022年第4期15卷 903-937页

作者： qiang Du Zuoqiang shi Department of Applied Physics and Applied Mathematics and Data Science InstituteColumbia UniversityNew YorkNY 10027USA Yau Mathematical Sciences Center Tsinghua UniversityBeijing 100084China Yanqi Lake Beijing Institute of Mathematical Sciences and Applications Beijing 101408China

In this paper,we introduce a nonlocal model for linear steady Stokes system with physical no-slip boundary *** use the idea of volume constraint to enforce the no-slip boundary condition and prove that the nonlocal model is *** also show that and the solution of the nonlocal system converges to the solution of the original Stokes system as the nonlocality vanishes.

关键词： Nonlocal Stokes system nonlocal operators smoothed particle hydrodynamics incompressible flows well-posedness local limit

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α1A受体阻滞剂在上尿路结石术后应用的临床研究

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昆明医科大学学报 2012年第11期33卷 107-110页

作者：毕晓方史云强钟一鸣李珲王春晖昆明医科大学附属延安医院泌尿外科云南昆明650051 昆明医科大学第二临床学院云南昆明650101

目的评价α1A受体阻滞剂在上尿路结石术后对残留结石排出的影响,及其对输尿管支架管综合症的改善作用.方法回顾性研究2008年6月至2011年8月,对延安医院128例上尿路结石患者采用输尿管镜治疗输尿管结石102例,经皮肾镜取石术治疗输尿管上... 详细信息

目的评价α1A受体阻滞剂在上尿路结石术后对残留结石排出的影响,及其对输尿管支架管综合症的改善作用.方法回顾性研究2008年6月至2011年8月,对延安医院128例上尿路结石患者采用输尿管镜治疗输尿管结石102例,经皮肾镜取石术治疗输尿管上段结石和肾结石26例,所有患者术后均留置D-J管,治疗组68例术后给给予坦索罗辛0.2 mg口服,对照组60例.观察残留结石的排除成功率、排除时间,2周后D-J管拔除前的下尿路症状、生活质量及疼痛改善的情况.结果坦索罗辛治疗组残留结石完全排出60例,对照组42例;与对照组比较,治疗组对下尿路症状的改善情况、生活质量评分、视觉模拟评分(VAS)均优于对照组(P<0.05).结论α1A受体阻滞剂对上尿路结石术后具有明确的辅助排出残留结石的作用,并能有效缓解输尿管支架管综合症,改善患者术后的生活质量,值得临床上推广应用.

关键词： α1A受体阻滞剂尿石症治疗

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Theoretical methods for excited state dynamics of molecules and molecular aggregates

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Science China Chemistry 2013年第9期56卷 1271-1276页

作者： shi qiang CHEN Hui Beijing National Laboratory for Molecular Science (BNLMS) Institute of ChemistryChinese Academy of Sciences

This contribution provides a summary of proposed theoretical and computational studies on excited state dynamics in molecular aggregates, as an important part of the National Natural Science Foundation (NNSF) Major Project entitled "Theoretical study of the low-lying electronic excited state for molecular aggregates". This study will focus on developments of novel methods to simulate excited state dynamics of molecular aggregates, with the aim of understanding several important chemical physics processes, and providing a solid foundation for predicting the opto-electronic properties of organic functional materials and devices. The contents of this study include: (1) The quantum chemical methods for electronic excited state and electronic couplings targeted for dynamics in molecular aggregates; (2) Methods to construct effective Hamiltonian models, and to solve their dynamics using system-bath approaches; (3) Non-adiabatic mixed quantum-classic methods targeted for molecular aggregates; (4) Theoretical studies of charge and energy transfer, and related spectroscopic phenomena in molecular aggregates.

关键词： excited state dynamics molecular aggregates effective Hamiltonian models mixed quantum-classical dynamics

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Change monitoring of earth rotation parameter with Maglev gyroscope precessional torque

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中国有色金属学会会刊：英文版 2011年第S3期21卷 589-593页

作者： YANG Zhi-qiang, GONG yun, shi Zhen, LI yun Geological Engineering and Geomatics Institute, Chang’an University, Xi’an 710054, China Geological Engineering and Geomatics Institute Chang'an University Xi'an 710054 China

Through analyzing the relationship between gyro dynamic torques produced by the changes of earth rotation parameters (ERP), a method of measuring the earth rotation parameters was proposed and explored by using gyroscope. The preliminary experiments were carried out using GAT Maglev Gyro Station (which is self-developed by China). Considering the measurement and expanding-application of the earth rotation parameters, some ideas and opinions about the structure design, measurement methods and data processing of gyro were proposed, and some outlook of the expanding-application of the gyroscope in geodetic and geophysical fields were done. The experimental results show that using the high-precision gyroscope to determine the changes of ERP is feasible, with the emergence of ultra-high precision gyro; it is possible for determining the earth rotation parameters by gyro in stead of by current complex space surveying technology.

关键词： Maglev gyroscope earth rotation parameters (ERP) precessional torque pole motion length of day

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