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Journal of Forestry Research 2020年第3期31卷 1053-1060页

作者： Lei Yu Yuliang Liang Yizhuo Zhang Jun Cao Mechanical and Electrical College Northeast Forestry UniversityHarbin 150040People’s Republic of China

This study used near-infrared(NIR)spectroscopy to predict mechanical properties of wood.NIR spectra were collected in wavelengths 900–1700 nm,and spectra averaged by radial and tangential surface spectra were used to establish a partial least square(PLS)model based on correlation local embedding(CLE).Mongolian oak(Quercus mongolica Fisch.ex Ledeb.)was used to test the eff ectiveness of the model.The cross-validation method was used to verify the robustness of the CLE–PLS model.Ninety samples were tested as the calibration set and forty-fi ve as the validation set.The results show that the prediction coeffi cient of determination(R2 p)is 0.80 for MOR,and 0.78 for MOE.The ratio of performance to deviation is 2.23 for MOR and 2.15 for MOE.

关键词： Modulus of rupture Modulus of elasticity Near-infrared Correlation local embedding partial least square

Physiological and biochemical appraisal for mulching and partial rhizosphere drying of cotton

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Journal of Arid Land 2019年第5期11卷 785-794页

作者： Rashid IQBAL Muhammad A S RAZA Muhammad F SALEEM Imran H KHAN Salman AHMAD Muhammad S ZAHEER Muhammad U ASLAM Imran HAIDER Department of Agronomy College of Agriculture and Environmental SciencesIslamia University of BahawalpurBahawalpur 63100Pakistan Department of Agronomy University of AgricultureFaisalabad 38040Pakistan Department of Agronomy Nanjing Agricultural UniversityNanjing 210000China

Water is the main factor for the healthy life of plant.One of the main negative effects of climate change is the increasing scarcity of water that is lethal for plant.Globally,for water deficit regions(arid and semi-arid),drought is the main factor responsible for low production of agriculture,especially for cotton.Great efforts have been and are being made to find alternatives to water saving practices.This study aimed to examine the effects of partial rhizosphere drying(PRD,half of the root system irrigated at one event,and the other half irrigated in the next event,and so on)with and/or without various mulching treatments on physiological and biochemical traits of cotton.To explore this objective,we laid out experiments in completely randomized design with factorial arrangement in the Islamia University of Bahawalpur,Pakistan in 2016.Two factors included were four mulching treatments(M0,no mulching;M1,black plastic mulching;M2,wheat straw mulching;and M3,cotton sticks mulching)and two irrigation levels(I0,control(full irrigation);and I1,PRD).Fisher's analysis of variance among means of treatments was compared using least significant difference test at 5% probability level.Results revealed that the maximum plant height,leaf area,leaf gas exchange(photosynthetic rate and stomata conductance),chlorophyll,proline and total sugar contents,and enzyme activities were higher under M2 than under other three mulching treatments.As for irrigation levels,higher values of plant height,photosynthesis and water related parameters(leaf water potential,leaf osmotic potential,leaf turgor potential,etc.)were recorded.Contents of total sugar and proline and activities of antioxidant enzymes were significantly higher in PRD-treated plants than in control plants.It was concluded that combined application of PRD and mulching was more effective than the rest of the treatments used in the experiment.Similar study can be conducted in the field by applying irrigation water in alternate rows in semi-arid regions.

关键词： antioxidant enzymes mulching partial rhizosphere drying photosynthetic rate stomatal conductance

Numerical Methods for Solving Space Fractional partial Differential Equations Using Hadamard Finite-Part Integral Approach

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Communications on Applied Mathematics and Computation 2019年第4期1卷 505-523页

作者： Yanyong Wang Yubin Yan Ye Hu Department of Mathematics Luliang University38 Binghe North East RoadLuliangShanxi 033000China Department of Mathematics University of ChesterCHI 4BJ ChesterUK

We introduce a novel numerical method for solving two-sided space fractional partial differential equations in two-dimensional case.The approximation of the space fractional Riemann-Liouville derivative is based on the approximation of the Hadamard finite-part integral which has the convergence order O(h^3-a),where h is the space step size and α∈(1,2)is the order of Riemann-Liouville fractional derivative.Based on this scheme,we introduce a shifted finite difference method for solving space fractional partial differential equations.We obtained the error estimates with the convergence orders O(τ+h^3-a+h^β),where τ is the time step size and β>0 is a parameter which measures the smoothness of the fractional derivatives of the solution of the equation.Unlike the numerical methods for solving space fractional partial differential equations constructed using the standard shifted Griinwald-Letnikov formula or higher order Lubich's methods which require the solution of the equation to satisfy the homogeneous Dirichlet boundary condition to get the firstorder convergence,the numerical method for solving the space fractional partial differential equation constructed using the Hadamard finite-part integral approach does not require the solution of the equation to satisfy the Dirichlet homogeneous boundary condition.Numerical results show that the experimentally determined convergence order obtained using the Hadamard finite-part integral approach for solving the space fractional partial differential equation with non-homogeneous Dirichlet boundary conditions is indeed higher than the convergence order obtained using the numerical methods constructed with the standard shifted Griinwald-Letnikov formula or Lubich's higher order approximation schemes.

关键词： Riemann-Liouville fractional derivative Space fractional partial differential equation Error estimates

基于虚拟力弹簧方法的partial Finger动力学建模与仿真

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机械设计与制造 2013年第3期 178-180页

作者：杨会生姜力中国科学院长春光学精密机械与物理研究所吉林长春130033 哈尔滨工业大学黑龙江哈尔滨150001

为了掌握partial Finger的运动学规律和动力学特性,判断其结构参数对partial Finger使用性能的影响,准确评价其真实的工作状态,根据partial Finger的机械结构,建立了基于虚拟力弹簧方法的partial Finger动力学模型,并利用Matlab软件对... 详细信息

为了掌握partial Finger的运动学规律和动力学特性,判断其结构参数对partial Finger使用性能的影响,准确评价其真实的工作状态,根据partial Finger的机械结构,建立了基于虚拟力弹簧方法的partial Finger动力学模型,并利用Matlab软件对所建立的动力学模型进行数值求解,通过对比相同工作状态下的动力学模型以及Adams仿真结果,初步确定虚拟力弹簧的弹性系数量级取104N/mm时,动力学模型和Adams仿真所得结果一致,证明动力学模型正确,并为partial Finger机械结构的进一步设计、完善提供了理论依据。

关键词： partial Finger 虚拟力弹簧动力学 ADAMS

Effect of partial splenic embolization on the immune function of cirrhosis patients with hypersplenism

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Asian Pacific Journal of Tropical Medicine 2016年第7期9卷 688-692页

作者： Gui-Yun Jin Chuan-Zhu Lv Tang Deng Shao-Wen Cheng Chao-Qian Li Guangxi Medical University Hainan Medical University the Affiliate Hospital of Hainan Medical College

Objective:To discover the effect of partial splenic embolization on the immune function of cirrhotic patients with hypersplenism.Methods:Patients involved in the study were enrolled and divided into three groups,including control group,experimental group,and complication group.Numbers of CD3^+,CD4^+ and CD8^+ T cells and CD4^+CD25^+CDl27^(low/-) Treg cells in the peripheral blood of patients before surgery,1 month,6 months,1 year,and 2 years after surgery were analyzed by fluorescence active cell sorting(FACS).Contents of immunoglobulins(IgA,IgG and IgM) were analyzed by auto immunoassay analyzer.Results:In the peripheral blood of patients from experimental group,numbers of CD3^+,CD4^+ and CD8^+ T cells initially declined,but afterwards increased to normal level;in the peripheral blood of patients from complication group,CD3^+ and CD8^+ T cells showed the same trend,but the number of CD4^+ T cells was below normal level at all detection times.Furthermore,CD3^+,CD4^+ and CD8^+ T cells in the peripheral blood of patients from complication group were initially less than those in experimental group,and afterwards were comparable between two groups.In patients from both experimental group and complication group,the number of CD4^+CD25^+CDl27^(low/-)Treg cells increased 1 month and 6 months after surgery,and gradually restored to normal level.CD4^+CD25^+CDl27^(low/-)Treg cell counts in patients from complication group were initially more than those in patients from experimental group 1 month and 6 months after surgery,but then they were comparable.Furthermore,contents of immunoglobulins(IgA,IgG and IgM) were comparable in three groups at all detection times.Conclusion:partial splenic embolization influenced the immune function of cirrhotic patients with hypersplenism in the short term but the immune function could afterwards gradually restore to normal.Our results implicated that measures that prevent infection and improve immune function were necessary in early stage after undergoing PSE in order to reduce complicatio

关键词： Viral hepatitis type B Cirrhosis Hypersplenism partial splenic embolization Immune function

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偏缠绕结构的上同调（英文）

Chinese Quarterly Journal of Mathematics 2019年第1期34卷 66-74页

作者：贾玲 Department of Mathematics and Statistics

In this paper we mainly reveal the rich cohomology theories for partial entwining structures.

关键词： partial entwining structure partial entwined module cohomology

Research on Time-Domain Transfer Impedance Measurement Technology for High Frequency Current Transformers in partial Discharge Det ection of Cables

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Journal of Shanghai Jiaotong university(Science) 2020年第1期25卷 10-17页

作者：宋思蒙陈孝信钱勇王辉张悦盛戈皞江秀臣 Department of Electrical Engineering Shanghai Jiao Tong UniversityShanghai 200240.China State Grid Zhejiang Electric Power Research Institute Hangzhou 310014China

We focus on the high frequency current method which is widely applied in the partial discharge(PD)detection of cables.Aiming at guaranteeing the accuracy of this method,we study an innovative time-domain technology for effectively measuring the transfer impedance of the high frequency current transformers(HFCTs).The proposed technology called pulse injection method obtains the system response under the excitation of the wide-band instantaneous pulse signal.Firstly,by studying the working principle of HFCTs,we summarize that the bandwidth of the selected signal acquisition device should be at least 100 MHz to ensure measurement accuracy.Secondly,Gauss pulse and square wave pulse are generated to determine the effects of different sources.The measurement results indicate that Gauss pulse is more suitable for pulse injection method,and the rise time should be under 10 ns to improve the starting frequency of oscillation distortion.Finally,the transfer impedance curves of five types of HFCTs are acquired by both pulse injection and traditional point-frequency methods.The measurement results show a remarkable consistency between two methods.However,pulse injection method requires the simpler operation and lias a higher resolution,obviously improving the measurement efficiency and bet ter displaying the details of the transfer impedance curves.

关键词： partial discharge(PD) high frequency current transformer(HFCT) transfer impedance pulse measurement

Characterizing and estimating rice brown spot disease severity using stepwise regression,principal component regression and partial least-square regression

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2007年第10期8卷 738-744页

作者： LIU Zhan-yu1, HUANG Jing-feng1, SHI Jing-jing1, TAO Rong-xiang2, ZHOU Wan3, ZHANG Li-li3 (1Institute of Agriculture Remote Sensing and Information System Application, Zhejiang University, Hangzhou 310029, China) (2Institute of Plant Protection and Microbiology, Zhejiang Academy of Agricultural Sciences, Hangzhou 310021, China) (3Plant Inspection Station of Hangzhou City, Hangzhou 310020, China) Institute of Agriculture Remote Sensing and Information System Application Zhejiang University Hangzhou 310029 China.

Detecting plant health conditions plays a key role in farm pest management and crop protection. In this study, measurement of hyperspectral leaf reflectance in rice crop (Oryzasativa L.) was conducted on groups of healthy and infected leaves by the fungus Bipolaris oryzae (Helminthosporium oryzae Breda. de Hann) through the wavelength range from 350 to 2 500 nm. The percentage of leaf surface lesions was estimated and defined as the disease severity. Statistical methods like multiple stepwise regression, principal component analysis and partial least-square regression were utilized to calculate and estimate the disease severity of rice brown spot at the leaf level. Our results revealed that multiple stepwise linear regressions could efficiently estimate disease severity with three wavebands in seven steps. The root mean square errors (RMSEs) for training (n=210) and testing (n=53) dataset were 6.5% and 5.8%, respectively. Principal component analysis showed that the first principal component could explain approximately 80% of the variance of the original hyperspectral reflectance. The regression model with the first two principal components predicted a disease severity with RMSEs of 16.3% and 13.9% for the training and testing dataset, respec-tively. partial least-square regression with seven extracted factors could most effectively predict disease severity compared with other statistical methods with RMSEs of 4.1% and 2.0% for the training and testing dataset, respectively. Our research demon-strates that it is feasible to estimate the disease severity of rice brown spot using hyperspectral reflectance data at the leaf level.

关键词： Hyperspectral reflectance Rice brown spot partial least-square (PLS) regression Stepwise regression Principal component regression (PCR)

基于partial EIV模型的三维坐标转换参数求解方法

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江西科学 2017年第3期35卷 355-359,432页

作者：邱德超鲁铁定东华理工大学测绘工程学院南昌330013 流域生态与地理环境监测国家测绘地理局重点实验室南昌330013

针对三维坐标转换参数求解的问题,首先根据三维坐标转换模型中系数矩阵既含有随机元素又含有非随机元素的特点,把三维坐标转换模型转换成非线性partial EIV模型,最后线性化成类似于最小二乘间接平差形式,采用迭代的方法求解转换参数,并... 详细信息

针对三维坐标转换参数求解的问题,首先根据三维坐标转换模型中系数矩阵既含有随机元素又含有非随机元素的特点,把三维坐标转换模型转换成非线性partial EIV模型,最后线性化成类似于最小二乘间接平差形式,采用迭代的方法求解转换参数,并推导精度评定公式。最后,通过算例数据进行验证,结果表明基于partial EIV的三维坐标转换模型总体最小二乘方法的正确性、高效性。

关键词： partial EIV模型三维坐标转换线性化总体最小二乘

partial Nephrectomy for Renal Cell Carcinoma: Risk Factors for Acute Post-Operative Hemorrhage and Impact on Subsequent Hospital Course and Complete Nephrectomy Rate. An Analysis of 200 Consecutive Cases

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International Journal of Clinical Medicine 2013年第12期4卷 5-9页

作者： James Cavalcante Alan Perrotti Philip Rabadi Alicia McCarthy Michael Perrotti Urologic Oncology Service Saint Peter’s Hospital Cancer Care Center Saint Peter’s Health Partners Albany New York USA

Purpose: Clinical guidelines recommend partial nephrectomy (PN) as the preferred method of surgical excision of the small renal tumor whenever feasible. PN has comparable cancer cure rates to that of radical nephrectomy in this setting, and decreased risk of chronic kidney disease. A recognized devastating complication following partial nephrectomy is acute post-operative hemorrhage (APOH) from the reconstructed kidney. Risk factors for hemorrhage following partial nephrectomy remain poorly elucidated, as does the impact of hemorrhage on subsequent hospital stay. Identification of risk factors for hemorrhage may lead to a better understanding of and reduction of this complication. Material and Methods: We utilized a prospectively managed database comprised of patients undergoing open partial nephrectomy at our institution by the same surgical team from January 2006 to July 2012. Clinicopathologic factors assessed APOH for their relationships, including patient age, gender, diabetes, smoking, hypertension, coronary artery disease, American Society of Anesthesia Score (ASA), tumor size, RENAL nephrotomy score, pathologic result, cancer margin status, operative time, and intra-operative blood loss. The impact of APOH on subsequent hospital course was evaluated and compared with the entire cohort. Results: Data were analyzed from 200 consecutive patients. We identified 7 patients (3.5%) who experienced APOH. Compared with the entire cohort, APOH resulted in an increased hospital length of stay (median, 5 days;range, 2-11 days, p = 0.001), an increased transfusion requirement (median, 6 units;range, 1-16 units. p = 0.001), a greater risk of selective angiographic embolization (median, 2 procedures;range, 0-3, p = 0.001), and completion nephrectomy (n = 2, p = 0.001). One patient in the APOH group experienced cardiac arrest and was resuscitated. Clinicopathologic factors associated

关键词： Kidney Neoplasms partial Nephrectomy Renal Cell Carcinoma