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Prediction and Simulation of Microstructure of Ti-15-3 Alloy

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Journal of Materials Science & Technology 2003年第Z1期19卷 161-163页

作者： ping li Kemin xue Yan LU Jianrong TAN College of Mechanical and Energy Engineering Zhejiang University Hangzhou 310027 China School of Materials Science and Engineering Harbin Institute of Technology Harbin 150001 China School of Materials Science and Engineering Harbin Institute of Technology Harbin 150001 China College of Mechanical and Energy Engineering Zhejiang University Hangzhou 310027 China

Ti-15-3 alloy is a new metastableβ-type titanium. The influence of hot deformation parameters on the microstructureof Ti-15-3 alloy after solution treatment has been studied by isothermal compression tests as well as quantitativemetallographic analysis. On the basis of the data obtained from the tests, predicting models for equivalent grainsize and recrystallization volume fraction have been established with an artificial neural network method. An FEnumerical simulation system has been developed to simulate the distribution of microstructure in Ti-15-3 alloy afterhot back extrusion and solution treatment by combining the neural network model with thermal-mechanical coupledrigid-viscoplastic FE model. Corresponding experimental research is performed. The agreement of the simulatedresults with measured ones shows that the simulation system is reliable.

关键词： Ti-15-3 alloy, Neural retwork, FE model, Simulation

Controller Design for Electric Power Steering System Using T-S Fuzzy Model Approach

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International Journal of Automation and computing 2009年第2期6卷 198-203页

作者： Xin li xue-ping Zhao Jie Chen School of Mechanical Engineering Shanghai Jiao Tong University Shanghai 200240 PRC

Pressure ripples in electric power steering （EPS） systems can be caused by the phase lag between the driver s steering torque and steer angle, the nonlinear frictions, and the disturbances from road and sensor noise especially during high-frequency maneuvers. This paper investigates the use of the robust fuzzy control method for actively reducing pressure ripples for EPS systems. Remarkable progress on steering maneuverability is achieved. The EPS dynamics is described with an eight-order nonlinear state-space model and approximated by a Takagi-Sugeno （T-S） fuzzy model with time-varying delays and external disturbances. A stabilization approach is then presented for nonlinear time-delay systems through fuzzy state feedback controller in parallel distributed compensation （PDC） structure. The closed-loop stability conditions of EPS system with the fuzzy controller are parameterized in terms of the linear matrix inequality （LMI） problem. Simulations and experiments using the proposed robust fuzzy controller and traditional PID controller have been carried out for EPS systems. Both the simulation and experiment results show that the proposed fuzzy controller can reduce the torque ripples and allow us to have a good steering feeling and stable driving.

关键词： Electric power steering (EPS) fuzzy control Takagi-Sugeno (T-S) model parallel distributed compensation (PDC) timedelay linear matrix inequality (LMI).

Multi-slice computed tomography manifestations of hepatic epithelioid angiomyolipoma

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World Journal of Gastroenterology 2014年第12期20卷 3364-3368页

作者： Chun-Lai Dai li-ping xue Yu-Mei li Department of Radiology the First Hospital of Jilin University Press of Maternal and Child Health Care of China Medicine Periodical House of Jilin Province Department of Pediatrics the First Hospital of Jilin University

AIM: To explore the characteristics of multi-slice computed tomography (CT) manifestations of hepatic epithelioid angiomyolipoma (HEA), improve the rate of accurate diagnosis, and reduce the misdiagnostic rate.

关键词： liver Epithelioid Angiomyolipoma Computed tomography

Large-Mode-Area Double-Cladding Photonic Crystal Fiber Laser in the Watt Range at 980nm

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Chinese Physics Letters 2011年第8期28卷 119-121页

作者： li ping-xue ZHANG xue-Xia liU Zhi CHI Jun-Jie Institute of Laser Engineering Beijing University of TechnologyBeijing 100124

We report on a quasi-three-level large-mode-area double-clad Yb-doped fiber laser that adopts a linear cavity consisting of a 0°fiber end and a cavity *** kinds of Yb−doped photonic crystal fiber(PCF)with different inner-clads(170µm and 200µm)and absorption coefficients(4.5 dB/m and 3 dB/m)are used as the gain *** optimizing the structure and elements of the cavity,maximum output powers of 1.24 W and 1.1 W were yielded with optical conversion efficiencies of 7.8%and 6.8%when the fiber lengths were 25 cm and 40 cm with 170µm and 200µm inner-claddings,respectively.

关键词： fiber Crystal cavity

Application value of multi-slice spiral computed tomography for imaging determination of metastatic lymph nodes of gastric cancer

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World Journal of Gastroenterology 2013年第34期19卷 5732-5737页

作者： Chun-Lai Dai Zhi-Gang Yang li-ping xue Yu-Mei li Department of Radiology the First Hospital of Jilin University Press of Maternal and Child Health Care of China Medicine Periodical House of Jilin Province Department of Pediatrics the First Hospital of Jilin University

AIM:To evaluate the application value of multi-slice spiral computed tomography(MSCT)for imaging determination of metastatic lymph nodes of gastric cancer and to explore reasonable diagnostic ***:Sixty patients with gastric cancer underwent 64 MSCT scans before *** cancer samples and perigastric lymph nodes were obtained after operation,formalin fixation and haematoxylineosin *** metastatic conditions of gastric cancer and perigastric lymph nodes were determined under a light microscope.A total of 605 lymph nodes were grouped and assessed according to distribution,size,shape and degree of lymph node ***,the findings were compared with the postoperative pathological ***:Among 605 lymph nodes,358 were confirmed as metastatic,accounting for 59.2%.A total of535 lymph nodes were detected in original axis images combined with multiplanar reconstruction images of *** metastatic lymph nodes had specific signs in computed *** study showed that the long diameter of lymph nodes≥8 mm indicated metastasis;the sensitivity and specificity were 79.6%and78.8%,*** difference of the mean value of lymph node enhancement density≥80 Hu indicated metastasis;the sensitivity and specificity were81.6%and 75.6%,*** ratio of short diameter to long diameter of lymph nodes≥0.7 indicated metastasis;the sensitivity and specificity were85.6%and 71.8%,***:MSCT is a non-invasive and reliable method for preoperative examination of gastric *** and specificity for prediction of lymph node metastasis are high.

关键词： X-ray computer Gastric cancer Metastatic lymph nodes

Photoluminescence Quenching of Porous Silicon by Molecule Adsorption

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Chinese Physics Letters 1998年第10期15卷 756-757页

作者： li xue-ping YIN Feng ZHANG Zhen-zong XIAO Xu-rui Institute of Photographic Chemistry Chinese Academy of SciencesBeijing 100101

The photoluminescence of HNO3 chemically oxidized porous silicon can be easily quenched by organic adsorbates,and the ability of quenching was quantitatively estimated by two models-Langmuir adsorption isotherm and Stern-Volmer.A strong steric effect of organic adsorbates on the photoluminescence quenching of oxidized porous silicon was observed.

关键词： quenching oxidized Adsorption

Effect of admission hypertriglyceridemia on the episodes of severe acute pancreatitis

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World Journal of Gastroenterology 2008年第28期14卷 4558-4561页

作者： li-Hui Deng ping xue Qing Xia Xiao-Nan Yang Mei-Hua Wan Department of Integrated Traditional Chinese and Western Medicine West China Hospital Sichuan University Chengdu 610041 Sichuan Province China

AIM： To investigate the effect of admission hypertriglyceridemia （HTG） on the episodes of severe acute pancreatitis （SAP）. METHODS： One hundred and seventy-six patients with SAP were divided into HTG group （n = 45） and control group （n = 131） according to admission triglyceride （TG） ≥ 5.65 mmol/L and 〈 5.65 retool/L, respectively. Demographics, etiology, underlying diseases, biochemical parameters, Ranson＇ s score, acute physiology and chronic heath evaluation Ⅱ （APACHE Ⅱ） score, Balthazar＇s computed tomography （CT） score, complications and mortality were compared. Correlation between admission TG and 24-h APACHE Ⅱ score was analyzed. RESULTS： SAP patients with HTG were younger （40.8 ± 9.3 years vs 52.6 ± 13.4 years, P 〈 0.05） with higher etiology rate of overeating, high-fat diet （40.0% vs 14.5%, P 〈 0.05） and alcohol abuse （46.7% vs 23.7%, P 〈 0.01）, incidence rate of hypocalcemia （86.7% vs 63.4%, P 〈 0.01） and hypoalbuminemia （84.4% vs 60.3%, P 〈 0.01）, 24-h APACHE Ⅱ score （13.6 ± 5.7 vs 10.7 ± 4.6, P 〈 0.01） and admission serum glucose （17.7 ± 7.7 vs 13.4 ± 6.1, P 〈 0.01）, complication rate of renal failure （51.1% vs 16.8%, P 〈 0.01）, shock （37.9% vs 14.5%, P 〈 0.01） and infection （37.4% vs 18.3%, P 〈 0.01） and mortality （13.1% vs 9.1%, P 〈 0.01）. Logistic regression analysis showed a positive correlation between admission TG and 24-h APACHE Ⅱ score （r = 0.509, P = 0.004）.CONCLUSION： The clinical features of SAP patients with HTG are largely consistent with previous studies, HTG aggravates the episodes of SAP.

关键词： Clinical study Hypertriglyceridemia Severe acute pancreatitis Clinical features Outcome

0.05% atropine on control of myopia progression in Chinese school children: a randomized 3-year clinical trial

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International Journal of Ophthalmology(English edition) 2023年第6期16卷 939-946页

作者： Qin Zhu Guang-Yong Tang Zhi-Juan Hua li-ping xue Yuan Zhou Jie-Ying Zhang Ying-Ting Zhu Xiao-Fan Zhang Department of Pediatric Ophthalmology Affiliated Hospital of Yunnan UniversityKunming 650021Yunnan ProvinceChina Department of Ophthalmology People’s Hospital of Xundian CountyKunming 655200Yunnan ProvinceChina BioTissue(Tissue Tech Inc.)Ocular Surface Centerand Ocular Surface Research&Education FoundationMiamiFL 33126USA

·AIM:To evaluate the effect of 0.05%atropine on the control of myopia for 2y(phase I)and on spherical equivalent refraction(SER)progression for 1y(phase II)after its withdrawal in Chinese myopic children.·METHODS:Totally 142 children with myopia were randomly assigned to the 0.05%atropine group or to the placebo *** phase I,children received 1 treatment for each eye *** phase II,the patients received no *** length(AL),SER,intraocular pressure(IOP)and atropine-related side effects were assessed at 6 months’intervals.·RESULTS:During phase I,the mean change of SER was-0.46±0.30 D in the atropine group,compared to-1.72±1.12 D in the placebo group(P0.05).Furthermore,the change in SER from the atropine group was 0.50±0.41 D,which was significantly lower than 0.72±0.60 D from placebo group,(P0.05).·CONCLUSION:The use of 0.05%atropine for two consecutive years may effectively control elongation of AL and thus progression of myopia,without significant SER progression 1y after atropine ***,treatment with 0.05%atropine daily for 2y is effective and safe.

关键词： atropine axial length spherical equivalent refraction children myopia

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光谱分析在煤结构研究中的进展

光谱学与光谱分析 2022年第2期42卷 350-357页

作者：李雪萍曾强新疆大学资源与环境科学学院新疆乌鲁木齐830042 新疆大学干旱生态环境研究所新疆乌鲁木齐830046 新疆大学绿洲生态教育部重点实验室新疆乌鲁木齐830046

煤结构是各类煤相关研究的微观基础,光谱分析作为煤结构研究的重要方法被广泛应用,其在煤结构研究中的进展对光谱分析方法的普及、应用和发展有重要意义。光谱分析方法研究煤结构已成为煤化工领域使用的常规方法,能够快速无损检测,对煤... 详细信息

煤结构是各类煤相关研究的微观基础,光谱分析作为煤结构研究的重要方法被广泛应用,其在煤结构研究中的进展对光谱分析方法的普及、应用和发展有重要意义。光谱分析方法研究煤结构已成为煤化工领域使用的常规方法,能够快速无损检测,对煤分子结构的破坏小,可为不同环境条件下煤物理化学性质的变化提供有效的检测手段。从光谱分析在煤质、大分子结构、煤中元素三个方面介绍光谱分析方法,主要对傅里叶变换红外光谱(FTIR)、Raman光谱分析、核磁共振谱(NMR)进行综述介绍,阐明其在煤结构研究中的发展历史、应用的关键研究结果及其意义。综合国内外煤结构研究中的多种光谱分析方法及应用现状发现:目前研究并没有彻底解决煤结构特征及性质变化的问题,缺乏对煤结构光谱特征信息共性的总结,未能形成煤中官能团和元素的不同光谱信息数据库,存在光谱特征峰与煤结构信息不对等的问题,即在某波长存在特征峰但无法与煤中官能团匹配,或煤官能团受元素组成、键能等影响对多波长产生响应的问题。现阶段对原煤自然状态下结构的研究已经不能满足煤应用中产生的问题,单一的光谱分析方法不能全面分析煤结构特征,且对影响煤结构光谱特征变化因素的研究较少,尤其是煤样的前处理和煤在萃取等过程中,前处理液和萃取剂对煤光谱特征的影响。展望光谱分析在煤结构的研究中可以从以下几方面入手:光谱分析与其他方法的联用以综合描述煤结构,如化学方法、高分辨率透射电镜(HRTEM)、扫描轨道显微镜(STM)、质谱(MS)等方法的联用,定性、定量全面分析煤结构特征;多种条件下煤结构及光谱特征,现阶段应利用光谱分析方法研究煤在多种条件下的结构特征及性质变化,解决煤在实际应用中的问题。如对煤进行氧化、氢化、热解、燃烧、低温、液化、汽化等处理,分析过程变化和产物特征,有助于推测母体煤的结构,了解煤的性质,控制煤物理化学过程变化中的产物,获取煤的精细化学品;煤光谱分析特征信息库建立,网络大数据背景下建立煤光谱分析特征信息库及可视化数据查询平台,实现多条件模拟假设,演示和探索煤结构在不同条件下的动态变化,利用人工智能、云计算方法实现煤各类光谱数据的处理分析,增强光谱数据信息挖掘,提升数据有效性和实用性。

关键词：光谱分析煤结构煤质分析元素分析