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Acta Mathematicae Applicatae Sinica 2012年第4期28卷 663-672页

作者： xi-ming cheng Qi GONG School of Applied Science Beijing Information Science and Technology University Academy of Mathematics and Systems Science Chinese Academy of Sciences Department of Statistics University of Missouri

Semiparametric transformation models provide a class of flexible models for regression analysis of failure time data. Several authors have discussed them under different situations when covariates are time- independent （Chen et al., 2002; cheng et al., 1995; Fine et al., 1998）. In this paper, we consider fitting these models to right-censored data when covariates are time-dependent longitudinal variables and, furthermore, may suffer measurement errors. For estimation, we investigate the maximum likelihood approach, and an EM algorithm is developed. Simulation results show that the proposed method is appropriate for practical application, and an illustrative example is provided.

关键词： EM algorithm linear random effects model maximum likelihood estimation measurement error

Recursive calibration for a lithium iron phosphate battery for electric vehicles using extended Kalman filtering

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2011年第11期12卷 818-825页

作者： xiao-song HU Feng-chun SUN xi-ming cheng National Engineering Laboratory for Electric Vehicles Department of Mechanical EngineeringBeijing Institute of Technology Beijing 100081 China

In this paper,an efficient model structure composed of a second-order resistance-capacitance network and a simply analytical open circuit voltage versus state of charge(SOC) map is applied to characterize the voltage behavior of a lithium iron phosphate battery for electric vehicles(EVs).As a result,the overpotentials of the battery can be depicted using a second-order circuit network and the model parameterization can be realized under any battery loading profile,without a special characterization *** order to ensure good robustness,extended Kalman filtering is adopted to recursively implement the calibration *** linearization involved in the calibration algorithm is realized through recurrent derivatives in a recursive *** results show that the recursively calibrated battery model can accurately delineate the battery voltage behavior under two different transient power operating conditions.A comparison with a first-order model indicates that the recursively calibrated second-order model has a comparable accuracy in a major part of the battery SOC range and a better performance when the SOC is relatively low.

关键词： Model calibration Lithium iron phosphate battery Electric vehicle (EV) Extended Kalman filtering

A General Additive-multiplicative Rates Model for Recurrent and Terminal Events

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Acta Mathematicae Applicatae Sinica 2015年第4期31卷 1115-1130页

作者： xi-ming cheng Fang-yuan KANG Jie ZHOU xin WANG School of Applied Science Beijing Information Science and Technology University School of Mathematical Science Capital Normal University

Recurrent events data with a terminal event （e.g. death） often arise in clinical and observational studies. Most of existing models assume multiplicative covariate effects and model the conditional recurrent event rate given survival. In this article, we propose a general mSditive-multiplicative rates model for recurrent event data in the presence of a terminal event, where the terminal event stop the further occurrence of recurrent events. Based on the estimating equation approach and the inverse probability weighting technique, we propose two procedures for estimating the regression parameters and the baseline mean function. The asymptotic properties of the resulting estimators are established. In addition, some graphical and numerical procedures are presented for model checking. The finite-sample behavior of the proposed methods is examined through simulation studies, and an application to a bladder cancer study is also illustrated.

关键词： additive-multiplicative rates estimating equation marginal model model checking recurrentevents terminal event

不同开路电压松弛时间下基于等效电路解构的锂离子电池荷电状态估计（英文）

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2017年第4期18卷 256-267页

作者： xi-ming cheng Li-guang YAO Michael PECHT Collaborative Innovation Center for Electric Vehicles in Beijing National Engineering Laboratory for Electric VehiclesDepartment of Vehicular Engineering Beijing Institute of Technology Center of Advanced Life Cycle Engineering University of Maryland

目的:开路电压是基于模型的电池荷电状态估计的必要参数,其测试耗时大、效率低。本文旨在测试各种电压松弛时间的荷电状态-开路电压关系,研究其对开路电压法和等效电路模型的荷电状态估计准确度的影响,提高开路电压测试效率。创新点:1.... 详细信息

目的:开路电压是基于模型的电池荷电状态估计的必要参数,其测试耗时大、效率低。本文旨在测试各种电压松弛时间的荷电状态-开路电压关系,研究其对开路电压法和等效电路模型的荷电状态估计准确度的影响,提高开路电压测试效率。创新点:1.通过电路解构方法,将二阶阻容电路分解为简单路,运用二阶段递推最小二乘法辨识电路模型的参数;2.基于递推最小二乘法和卡尔曼滤波算法,建立电路参数辨识和荷电状态估计的的联合自适应算法,研究电池电压松弛时间对基于等效电路模型的荷电状态估计的影响。方法:1.通过电路解构技术和理论推导,构建辨识二阶阻容等效电路参数的二阶段递推最小二乘法辨识方法(图2和公式(4)^(9));2.将二阶段递推最小二乘法和扩展卡尔曼滤波器集成,建立适应工况变化的电池模型参数辨识和状态估计的联合算法(图3);3.通过电池测试,建立多温度和多电压松弛时间的荷电状态与开路电压的关系,驱动自适应联合算法,获得既保证荷电状态估计准确度,又缩短开路电压测试时间的电压松弛时间。结论:1.二阶段递推最小二乘法既能简化矩阵计算,又能够保证电路参数的辨识非负性;2.联合自适应算法能够适应工况变化辨识模型参数和估计荷电状态;3.联合自适应算法的结果表明,5 min的电压松弛时间既能保证荷电状态估计性能,又能极大地提高开路电压测试效率。

关键词：锂离子电池开路电压荷电状态递推最小二乘法扩展卡尔曼滤波器

Molecular mechanism of pancreatic ductal adenocarcinoma:The heterogeneity of cancer-associated fibroblasts and key signaling pathways

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World Journal of Clinical Oncology 2025年第2期16卷 18-28页

作者： Zhong-Yuan Hu Ding Ding Yu Song Ya-Feng Deng cheng-ming Zhang Tao Yu First School of Clinical Medicine Shaanxi University of Chinese MedicineXianyang 712000Shaanxi ProvinceChina College of Acupuncture and Massage Shaanxi University of Chinese MedicineXianyang 712000Shaanxi ProvinceChina Graduate School Guangzhou University of Chinese MedicineGuangzhou 510000Guangdong ProvinceChina Digestive Department I Shaanxi Provincial Hospital of Traditional Chinese MedicineXi’an 710000Shaanxi ProvinceChina

Pancreatic ductal adenocarcinoma stands out as an exceptionally fatal cancer owing to the complexities associated with its treatment and diagnosis,leading to a notably low five-year survival *** study offers a detailed exploration of epidemiological trends in pancreatic cancer and key molecular drivers,such as mutations in CDKN2A,KRAS,SMAD4,and TP53,along with the influence of cancer-associated fibroblasts(CAFs)on disease *** particular,we focused on the pivotal roles of signaling pathways such as the transforming growth factor-βand Wnt/β-catenin pathways in the development of pancreatic cancer and investigated their application in emerging therapeutic *** study provides new scientific perspectives on pancreatic cancer treatment,especially in the development of precision medicine and targeted therapeutic strategies,and demonstrates the importance of signaling pathway research in the development of effective therapeutic *** studies should explore the subtypes of CAFs and their specific roles in the tumor microenvironment to devise more effective therapeutic methods.

关键词： Pancreatic cancer Fibroblasts Signaling pathways Tumor microenvironment

A TRUST REGION-TYPE METHOD FOR SOLVINGMONOTONE VARIATIONAL INEQUALITY

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Journal of Computational Mathematics 2000年第1期18卷 13-24页

作者： xi-ming Liang cheng-xian Xu Ji-xin Qian Institute of Industrial Process Control National Lab of Industrial Control TechnologyZhejiang UniversityHangzhou 310027China School of Science Xi’an Jiaotong UniversityXi’an 710049China

Presents a study which proposed to introduce a trust region-type modification of Newton method for the monotone inequality problem using merit function. Concepts of monotone mapping; Proof of convergence of algorithm ... 详细信息

关键词： variational inequality problem trust region method global convergence quadratic convergence

Topographic Characteristics for the Geomorphologic Zones in the Northwestern Edge of the Qinghai-Tibet Plateau

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Journal of Mountain Science 2013年第6期10卷 1039-1049页

作者： cheng Wei-ming ZHAO Shang-min ZHOU cheng-hu CHEN xi State Key Laboratory of Resources and Environmental Information System Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Department of Surveying and Mapping College of Mining Technology Taiyuan University of Technology xinjiang Institute of Ecology and Geography Chinese Academy of Sciences

Based on geomorphologic and digital elevation model(DEM) data, the topographic characteristics of the northwestern edge of the Qinghai-Tibet Plateau are analyzed. Five representative peaks are first determined according to the topographic profile maps for the ridge and piedmont lines, and then the topographic gradient characteristics are analyzed according to the representative topographic profile acquisition *** on the geomorphologic database data, the regions between the ridge and the piedmont lines are divided into four geomorphologic zones; and the topographic characteristics are finally analyzed for the different geomorphologic zones regions using the DEM data. The research results show that from the piedmont to the ridge, there exist four geomorphologic zones: arid, fluvial, periglacial and glacial. The arid has the lowest elevation, topographic gradient, relief and slope characteristics. The fluvial has lower elevation and the highest topographic gradient, but with lower relief and slope characteristics. With higher elevation, the periglcial has lower topographic gradient, but the highest relief and slope characteristics. The glacial has the highest elevation with higher topographic gradient, relief and slope characteristics.

关键词： Topographic characteristics Geomorphologic zone Topographic gradient Topographic profile map Qinghai-Tibet Plateau

Expressions of Thymidylate Synthase, Thymidine Phosphorylase, Class Ⅲ β-tubulin, and Excision Repair Cross-complementing Group 1 Predict Response in Advanced Gastric Cancer Patients Receiving Capecitabine Plus Paclitaxel or Cisplatin

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Chinese Journal of Cancer Research 2011年第4期23卷 288-294页

作者： ming Lu Jing Gao xi-cheng Wang Lin Shen Key Laboratory of Carcinogenesis and Translational Research(Ministry of Education) Department of Gastrointestinal OncologyPeking University School of Oncology Beijing Cancer Hospital & Institute Beijing 100142 China

Objective: To evaluate the role of class III β-tubulin (TUBB3), thymidylate synthase (TS), thymidine phosphorylase (TP), and excision repair cross-complementing group 1 (ERCC1) in clinical outcome of advanced gastric cancer patients receiving capecitabine plus paclitaxel or cisplatin. Methods: The clinical data and tumor specimens from 57 advanced gastric cancer patients receiving first-line capecitabine plus paclitaxel (cohort 1, n=36) and capecitabine plus cisplatin (cohort 2, n=21) were retrospectively collected, and TUBB3, TS, TP, and ERCC1 expressions were detected by real-time quantitative PCR. The associations between expressions of biomarkers and response or survival were analyzed statistically. Results: The median age of 57 patients was 57 years (range: 27–75 years) with 38 males and 19 females. Of all patients, the response rates of patients with high TP, low TP and high TS, low TS expressions were 57.1%, 27.6% (P=0.024), and 55.2%, 28.6% (P=0.042), respectively. Among cohort 1, the response rates and median overall survivals of patients with low and high TUBB3 expressions were 61.1% vs. 33.3% (P=0.095) and 13.8 months vs. 6.6 months (P=0.019), respectively; the response rate (87.5%) of patients with low TUBB3 and high TP expressions was higher than that (14.3%) of patients with high TUBB3 and low TP expressions (P=0.01). Among cohort 2, the response rates of patients with low ERCC1 and high ERCC1 expressions were 45.5% and 20.0% respectively (P=0.361). Conclusion: TUBB3, TS and TP expressions could predict the response of advanced gastric cancer patients receiving capecitabine-based and paclitaxel-based chemotherapy. These results will be further confirmed in future large samples.

关键词： Advanced gastric cancer TS/TP/TUBB3/ERCC1 Capecitabine Paclitaxel Cisplatin

Synthesis and characterization of new soluble poly(aryl ether nitrile)s containing phthalazinone moiety

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Chinese Chemical Letters 2007年第5期18卷 595-597页

作者： ming Jing Wang cheng Liu Li ming Dong xi Gao Jian Department of Polymer Science ＆ Materials Dalian University of Technology Dalian 116012 China

A series of novel poly（aryl ether nitrile）s containing phthalazinone moiety were synthesized by the nucleophilic displacement reaction of bisphenol-like monomers （I） with 2,6-difluorobenzonitrile. The inherent viscosities ranged from 0.46 to 1.07 dL g^-1. The glass transition temperatures were in the range of 277-295℃, and the temperatures for 10% weight loss in nitrogen atmosphere were found between 495 and 527 ℃. The structures of these resultant polymers were confirmed by FT-IR and 1^H NMR. Moreover, the properties of poly（aryl ether nitrile）s including solubility and crystallinity were also studied.

关键词： Poly(aryl ether nitrile)s Phthalazinone Heat-resistance Solubility

Effect of the geometric shapes of specimens on impact tensile tests

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2010年第10期11卷 817-821页

作者： Wei-fang XU xi-cheng HUANG Zhi-ming HAO Yang WANG Yuan-ming xiA Department of Modern Mechanics University of Science and Technology of China Hefei 230027 China Institute of Structural Mechanics China Academy of Engineering Physics Mianyang 621900 China

The geometric shapes of specimens are important in impact tensile tests because geometric shapes determine the stress states of the specimens, and precise geometric shapes can obtain proper material properties without non-material factors. The aim of this study was to investigate the 1D form of the stress by changing the length-to-diameter (L/D) ratios of specimens. The experiments were carried out on a split Hopkinson tensile bar (SHTB)-rotating disk indirect bar-bar tensile impact apparatus. The L/D ratios of the LY12CZ specimens used in the test ranged from 1 to 5. Results show that the specimens can be used to obtain exact parameters of materials under the proposed conditions when the L/D ratio is greater than 2. This is because the longer length will reduce or eliminate the effects of the interfaces.

关键词： Impact tensile Split Hopkinson tensile bar (SHTB) Length-to-diameter (L/D) ratios