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基于变异系数赋权与功效系数的医疗质量评价

中国医院统计 2009年第4期16卷 -页

作者：王彭德张朝元 Peng-de Chao-yuan 云南省大理市大理学院数学与计算机学院671003

目的主观赋权缺乏一定的科学性和客观性,为消除确定权重的人为干扰,依据变异程度确定各指标权重,使评价结果更客观. 方法运用变异系数赋权与功效系数法对医院医疗质量进行综合评价. 结果功效系数法原理简单、灵敏度高. 结论该方法... 详细信息

目的主观赋权缺乏一定的科学性和客观性,为消除确定权重的人为干扰,依据变异程度确定各指标权重,使评价结果更客观. 方法运用变异系数赋权与功效系数法对医院医疗质量进行综合评价. 结果功效系数法原理简单、灵敏度高. 结论该方法可在医疗卫生领域推广应用.

关键词：变异系数主观赋权功效系数法医疗质量评价 variation coefficient based quality evaluation 医院医疗质量医疗卫生领域综合评价指标权重推广应用人为干扰评价结果灵敏度高客观性方法变异程度科学性

Reducing component estimation for varying coefficient models with longitudinal data

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Science China Mathematics 2008年第2期51卷 250-272页

作者： TANG QingGuo~(1,2+) WANG JinDe~2 1 Institute of Sciences,People’s Liberation Army University of Science and Technology,Nanjing 210007,China 2 Department of Mathematics,Nanjing University,Nanjing 210093,China Institute of Sciences People’s Liberation Army University of Science and Technology Nanjing China Department of Mathematics Nanjing University Nanjing China

Varying-coefficient models with longitudinal observations are very useful in epidemiology and some other practical fields.In this paper,a reducing component procedure is proposed for es- timating the unknown functions and their derivatives in very general models,in which the unknown coefficient functions admit different or the same degrees of smoothness and the covariates can be time- dependent.The asymptotic properties of the estimators,such as consistency,rate of convergence and asymptotic distribution,are derived.The asymptotic results show that the asymptotic variance of the reducing component estimators is smaller than that of the existing estimators when the coefficient functions admit different degrees of smoothness.Finite sample properties of our procedures are studied through Monte Carlo simulations.

关键词： varying coefficient model longitudinal data nonparametric estimation reducing component estimators asymptotic normality

Combined value of apparent diffusion coefficient-standardized uptake value max in evaluation of post-treated locally advanced rectal cancer

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World Journal of Radiology 2015年第12期7卷 509-520页

作者： Davide Ippolito Davide Fior Chiara Trattenero Elena De Ponti Silvia Drago Luca Guerra Cammillo Talei Franzesi Sandro Sironi School of Medicine University of Milano-Bicocca Department of Diagnostic Radiology H S.Gerardo Monza Department of Medical Physics San Gerardo Hospital Department of Nuclear Medicine and PET Unit-Molecular Bioimaging Centre San Gerardo Hospital

AIM:To assess the clinical diagnostic value of functional imaging,combining quantitative parameters of apparent diffusion coefficient(ADC) and standardized uptake value(SUV)max,before and after chemo-radiation therapy,in prediction of tumor response of patients with rectal cancer,related to tumor regression grade at histology.METHODS:A total of 31 patients with biopsy proven diagnosis of rectal carcinoma were enrolled in our study.All patients underwent a whole body ^(18)FDG positron emission tomography(PET)/computed tomography(CT) scan and a pelvic magnetic resonance(MR)examination including diffusion weighted(DW) imaging for staging(PET1,RM1) and after completion(6.6 wk)of neoadjuvant treatment(PET2,RM2).Subsequently all patients underwent total mesorectal excision and the histological results were compared with imaging findings.The MR scanning,performed on 1.5 T magnet(Philips,Achieva),included T2-weighted multiplanar imaging and in addition DW images with b-value of 0 and 1000 mm^2/s.On PET/CT the SUVmax of the rectal lesion were calculated in PET1 and PET2.The percentage decrease of SUVmax(△SUV) and ADC(△ADC) values from baseline to presurgical scan were assessed and correlated with pathologic response classified as tumor regression grade(Mandard's criteria;TRG1 = complete regression,TRG5 = no regression).RESULTS:After completion of therapy,all the patients were submitted to surgery.According to the Mandard's criteria,22 tumors showed complete(TRG1) or subtotal regression(TRG2) and were classified as responders;9tumors were classified as non responders(TRG3,4 and5).Considering all patients the mean values of SUVmax in PET 1 was higher than the mean value of SUVmax in PET 2(P < 0.001),whereas the mean ADC values was lower in RM1 than RM2(P < 0.001),with a △SUV and △ADC respectively of 60.2%and 66.8%.The best predictors for TRG response were SUV2(threshold of4.4) and ADC2(1.29 × 10^(-3) mm^2/s) with high sensitivity and specificity.Combining in a single analysis both the obtained median value,the positive pred

关键词： Advanced rectal cancer Functional imaging FDG-PET/CT Magnetic resonance imaging Apparent diffusion coefficient Neoadjuvant treatment Tumor regression grade

Application of ERS-1 scatterometer data to studying land surfaces ──Distributive characteristic of backscattering coefficient over China land surfaces

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Chinese Science Bulletin 1998年第23期43卷 1950-1955页

作者： WANG Xiangyun 1, WANG Chao 2, GUO Huadong 2 and SHI Yangshen 1 1. Department of Earth Sciences, Nanjing University, Nanjing 210093, China 2. Institute of Remote Sensing Applications, Chinese Academy of Sciences, Beijing 100101, China Department of Earth Sciences Nanjing University Nanjing 210093 China Inst. of Remote Sensing Applications Chinese Academy of Sciences Beijing 100101 China

ERS 1 WSC data were obtained by international cooperation. The distributive characteristics of radar backscattering coefficient image of China land surface are analyzed and the research results are presented. The capability of ERS 1 WSC data for monitoring land surfaces is investigated. The results show that the radar backscattering coefficient images can reveal the natural landform features of China land. Using the WSC data can discriminate six types of major land coverage, including evergreen vegetation and snow covered region, vegetation and crops, mountains, grassland, desert and grassland, desert. On the whole, the radar backscattering coefficient image of China land is the synthesis of the vegetation map and terrain map. Statistical study of the typical terrain shows that the radar backscatter coefficients of China land range from -29 dB to -5 dB. The lowest value corresponds to the deserts of Badain Jaran, Takla Makan, and Tengger. The highest value corresponds to snow covered regions of Himalaya Mountains and Tianshan Mountains.

关键词： ERS 1 WSC radar backscattering coefficient land surfaces coverage.

Clinical outcomes of combined flow-pressure drop measurements using newly developed diagnostic endpoint:Pressure drop coefficient in patients with coronary artery dysfunction

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World Journal of Cardiology 2016年第3期8卷 283-292页

作者： Mohamed A Effat Srikara Viswanath Peelukhana Rupak K Banerjee Division of Cardiovascular Health and Diseases University of Cincinnati Medical CenterVeteran Affairs Medical Center Research Services Veteran Affairs Medical Center Depart-ment of Mechanical and Materials Engineering University of Cincinnati

AIM:To combine pressure and flow parameter, pressure drop coefficient(CDP) will result in better clinical outcomes in comparison to the fractional flow reserve(FFR) group. METHODS:To test this hypothesis, a comparison was made between the FFR 27.9 groups in this study, for the major adverse cardiac events [major adverse cardiac events(MACE): Primary outcome] and patients’ quality of life(secondary outcome). Further, a comparison was also made between the survival curves for the FFR 27.9 groups. Two-tailed χ~2 test proportions were performed for the comparison of primary and secondary outcomes. Kaplan-Meier survival analysis was performed to compare the survival curves of FFR 27.9 groups(MedcalcV10.2, Mariakerke, Belgium). Results were considered statistically significant for P 27.9 group(8.57%, 2 out of 35). Noteworthy is the reduction in the %MACE in the CDP > 27.9 group, in comparison to the FFR 27.9 groups. Survival analysis results suggest that the survival time for the CDP > 27.9 group(n = 35) is significantly higher(P = 0.048) in comparison to the survival time for the FFR < 0.75 group(n = 20). The results remained similar for a FFR = 0.80 cut-off. CONCLUSION: Based on the above, CDP could prove to be a better diagnostic end-point for clinical revascularization decision-making in the cardiac catheterization laboratories.

关键词： Pressure drop coefficient Interventional cardiology Intermediate coronary stenosis

PREDICTIVE EQUATION OF TRACER LIQUID DIFFUSION coefficient FROM VISCOSITY

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Chinese Journal of Chemical Engineering 1996年第3期4卷 18-23页

作者：钱仁渊范益群史美仁时钧南京化工大学化学工程系江苏南京

1 INTRODUCTIONAccurate data on molecular diffusion are required for the design of chemical and physi-cal processes where mass transfer plays an important role.Expressions for estimatingtracer diffusion coefficients(i.***.binary diffusion coefficients at infinite dilution)areavailable for a number of different systems .The Akgerman and Gainer equa-tion has been known to give good predictions for the diffusion coefficients of gases inliquids.This study provides an approximation approach for predicting diffusioncoefficients of binary liquid systems from their viscosities.

关键词： diffusion coefficient binary liquid system correlation

Estimation Method of Schedule-cost Correlation coefficient of Spaceflight Project

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工程科学（英文版） 2007年第3期5卷 69-75页

作者： Liu Yanqiong(Humanity and Social Science School,National University of Defence Technology,Changsha,410073,China)

To evaluate the cost risk and the schedule risk of the spaceflight project,the schedule-cost(S-C) correlation coefficient is directly appointed according to the experts' experience usually.This paper deduces SDMCU(the schedule distribution model considering the effect of the cost uncertainty),and then proposes the approximate formula to estimate the ln(S)-C correlation coefficient based on the models of SDMCU and CDMSU(the cost distribution model considering the effect of the schedule uncertainty).Furthermore,an approximate relationship expression of the S-C and the ln(S)-C correlation coefficients is put forward according to general facts and the Taylor expansion,and advanced by means of mass numerical validation is the general rule of obtaining the estimation value of the schedule-cost correlation coefficient based on the historical data.

关键词： spaceflight project risk cost schedule correlation coefficient

Wavelet estimation of the diffusion coefficient in time dependent diffusion models

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Science China Mathematics 2007年第11期50卷 1597-1610页

作者： Ping CHEN~(1,2+) Jin-de WANG~1 1 Department of Mathematics,Nanjing University,Nanjing 210093,China 2 School of Science,Nanjing University of Science and Technology,Nanjing 210094,China Department of Mathematics Nanjing University Nanjing China School of Science Nanjing University of Science and Technology Nanjing China

The estimation problem for diffusion coefficients in diffusion processes has been studied in many papers,where the diffusion coefficient function is assumed to be a 1-dimensional bounded Lipschitzian function of the state or the time only.There is no previous work for the nonparametric estimation of time-dependent diffusion models where the diffusion coefficient depends on both the state and the time.This paper introduces and studies a wavelet estimation of the time-dependent diffusion coefficient under a more general assumption that the diffusion coefficient is a linear growth Lipschitz function.Using the properties of martingale,we translate the problems in diffusion into the nonparametric regression setting and give the Lr convergence rate.A strong consistency of the estimate is established.With this result one can estimate the time-dependent diffusion coefficient using the same structure of the wavelet estimators under any equivalent probability measure.For example,in finance,the wavelet estimator is strongly consistent under the market probability measure as well as the risk neutral probability measure.

关键词： wavelet estimation time-dependent diffusion coefficient linear growth condition strong consistency

Improved computation of pressure coefficient and temperature coefficient of ultrasonic velocity in organic liquids

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Chinese Science Bulletin 1999年第19期44卷 1770-1773页

作者： Yigang Lu Jianxin Peng Jie Tong Yanwu Dong S China Univ Technol Dept Phys Guangzhou 510641 Peoples R China Shaanxi Normal Univ Appl Acoust Inst Xian 710062 Peoples R China

Based on Jacobson’s molecular free length theory in liquids and the relationship between the ultrasonic velocity and the molecular free length in organic liquids, the equations of pressure coefficient and temperature coefficient of ultrasonic velocity in organic liquids are derived . The calculated pressure coefficient and temperature coefficient of ultrasonic velocity are in good agreement with the measured results.

关键词： organic liquid ultrasonic velocity pressure coefficient of ultrasonic velocity temperature coefficient of ultrasonic velocity.