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Landslide prediction based on improved principal component analysis and mixed kernel function least squares support vector regression model

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Journal of Mountain Science 2021年第8期18卷 2130-2142页

作者： LI Li-min CHENG Shao-kang wen Zong-zhou School of Electronics and Information Xi’an Polytechnic UniversityXi’an710048China School of Automation Northwestern Polytechnical UniversityXi’an710072China

Landslide probability prediction plays an important role in understanding landslide information in advance and taking preventive *** factors can influence the occurrence of landslides,which is easy to have a curse of dimensionality and thus lead to reduce prediction *** the generalization ability of the model will also decline sharply when there are only small *** reduce the dimension of calculation and balance the model’s generalization and learning ability,this study proposed a landslide prediction method based on improved principal component analysis(PCA)and mixed kernel function least squares support vector regression(LSSVR)***,the traditional PCA was introduced with the idea of linear discrimination,and the dimensions of initial influencing factors were reduced from 8 to *** improved PCA can not only weight variables but also extract the original ***,combined with global and local kernel function,the mixed kernel function LSSVR model was framed to improve the generalization *** optimization algorithm(WOA)was used to optimize the ***,Root Mean Square Error(RMSE),the sum of squared errors(SSE),Mean Absolute Error(MAE),Mean Absolute Precentage Error(MAPE),and reliability were employed to verify the performance of the *** with radial basis function(RBF)LSSVR model,Elman neural network model,and fuzzy decision model,the proposed method has a smaller ***,the landslide warning level obtained from the landslide probability can also provide references for relevant decision-making departments in emergency response.

关键词： Landslide probability LSSVR Mixed kernel function Improved PCA Warning level

Optical biometry intraocular lens power calculation using different formulas in patients with different axial lengths

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International Journal of Ophthalmology(English edition) 2013年第2期6卷 150-154页

作者： Jia-kang Wang Shu-wen Chang Department of Ophthalmology Far Eastern Memorial Hospital Oriental Institute of Technology Department of Medicine National Yang Ming University

AIM: To investigate the predictability of intraocular lens (IOL) power calculation using the IOLMaster and different IOL power calculation formulas in eyes with various axial length (AL). METHODS: Patients were included who underwent uneventful phacoemulsification with IOL implantation in the Department of Ophthalmology, Far Eastern Memorial Hospital, Taipei, Taiwan, China from February 2007 to January 2009. Preoperative AL and keratometric values (Ks) were measured by IOLMaster optical biometry. Patients were divided into 3 groups based on AL less than 22mm (Group 1), 22-26mm (Group 2), and more than 26mm (Group 3). The power of the implanted IOL was used to calculate the predicted postoperative spherical equivalence (SE) by various formulas: the Haigis, Hoffer Q, Holladay 1, and SRK/T. The predictive accuracy of each formula was analyzed by comparing the difference between the actual and predicted postoperative SE (MedAE, median absolute error). All the patients had follow-up periods exceeding 3 months. RESULTS: Totally, there were 200 eyes (33 eyes in Group 1, 92 eyes in Group 2, 75 eyes in Group 3). In all patients, the Haigis had the significantly lower MedAE generated by the other formulas (P<0.05). In Group 1 to 3, the MedAE calculated by the Haigis was either significantly lower or comparable to those calculated by the other ***: Compared with other formulas using IOLMaster biometric data, the Haigis formula yields superior refractive results in eyes with various AL.

关键词： intraocular lens optical biometry calculation formula

A Bishop–Phelps–Bollobás Theorem for Asplund Operators

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Acta Mathematica Sinica,English Series 2020年第7期36卷 765-782页

作者： Li Xin CHENG Qing Jin CHENG kang kang XU wen ZHANG Zhe Ming ZHENG School of Mathematical Sciences Xiamen UniversityXiamen361005P.R.China

By characterizing Asplund operators through Fréchet differentiability property of convex functions,we show the following Bishop–Phelps–Bollobás theorem:Suppose that X is a Banach space,T:X→C(K)is an Asplund operator with║T║=1,and that x0∈SX,01-ε2/*** there exist xε∈SX and an Asplund operator S:X→C(K)of norm one so that║S(xε)║=1,x0-xε1-ε2/*** there exist yε*∈SY*,xε∈(±en),yε∈SY,and a strong Radon–Nikodym operator S:?1→Y of norm one so that(ⅰ)║S(xε)║=1;(ⅱ)S(xε)=yε;(ⅲ)║T-S║=1;(ⅴ)║y0*-yε*║<εand(ⅵ)║T*-S*║<ε,where(en)denotes the standard unit vector basis of?1.

关键词： Fréchet operator satisfy

Neoadjuvant immunotherapy for non-small cell lung cancer:State of the art

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Cancer Communications 2021年第4期41卷 287-302页

作者： Jin kang Chao Zhang wen-Zhao Zhong Guangdong Lung Cancer Institute Guangdong Provincial Key Laboratory of Translational Medicine in Lung CancerGuangdong Provincial People’s HospitalGuangdong Academy of Medical SciencesSchool of MedicineGuangzhouGuangdong 510080P.R.China Southern Medical University GuangzhouGuangdong 510515P.R.China

Lung cancer mortality has decreased over the past decade and can be partly attributed to advances in targeted therapy and *** checkpoint inhibitors(ICIs)have rapidly evolved from investigational drugs to standard of care for the treatment ofmetastatic non-small cell lung cancer(NSCLC).In particular,antibodies that block inhibitory immune checkpoints,such as programmed cell death protein 1(PD-1)and programmed cell death 1 ligand 1(PD-L1),have revolutionized the treatment of advanced NSCLC,when administered alone or in combination with *** is associated with higher response rates,improved overall survival(OS),and increased tolerability compared with conventional cytotoxic *** benefits may increase the utility of immunotherapy and its combinational use with chemotherapy in the neoadjuvant treatment of patients with *** findings from various ongoing clinical trials suggest that neoadjuvant ICIs alone or combined with chemotherapy may significantly reduce systemic recurrence and improve long-term OS or cure rates in resectable *** we further summarize the safety and efficacy of various neoadjuvant treatment regimens including immunotherapy from ongoing clinical trials and elaborate the role of neoadjuvant immunotherapy in patients with resectable *** addition,we discuss several unresolved challenges,including the evaluations to assess neoadjuvant immunotherapy response,the role of adjuvant treatment after neoadjuvant immunotherapy,the efficacy of treatment for oncogenic-addicted tumors,and predictive *** also provide our perspective on ways to overcome current obstacles and establish neoadjuvant immunotherapy as a standard of care.

关键词： chemoimmunotherapy clinical trials imaging immunotherapy neoadjuvant non-small cell lung cancer perioperative radiotherapy surgery

Experimental research on the instability propagation characteristics of liquid kerosene rotating detonation wave

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Defence Technology（防务技术） 2020年第6期16卷 1106-1115页

作者： Quan Zheng Hao-long Meng Chun-sheng weng Yu-wen Wu wen-kang Feng Ming-liang Wu National Key Laboratory of Transient Physics Nanjing University of Science and TechnologyNanjing210094China

In order to study the instability propagation characteristics of the liquid kerosene rotating detonation wave(RDW),a series of experimental tests were carried out on the rotating detonation combustor(RDC)with *** fuel and oxidizer are room-temperature liquid kerosene and preheated oxygenenriched air,*** experimental tests keep the equivalence ratio of 0.81 and the oxygen mass fraction of 35%unchanged,and the total mass flow rate is maintained at about 1000 g/s,changing the total temperature of the oxygen-enriched air from 620 K to 860 *** different types of instability were observed in the experiments:temporal and spatial instability,mode transition and *** interaction between RDW and supply plenum may be the main reason for the fluctuations of detonation wave velocity and pressure peaks with ***,the inconsistent mixing of fuel and oxidizer at different circumferential positions is related to RDW oscillate *** phenomenon of single-double-single wave transition is *** the transition,the initial RDW weakens until disappears,and the compression wave strengthens until it becomes a new RDWand propagates *** increased deflagration between the detonation products and the fresh gas layer caused by excessively high temperature is one of the reasons for the RDC quenching and re-initiation.

关键词： Rotating detonation wave Liquid kerosene Oxygen-enriched air Instability propagation characteristics Compression wave

Classical Electromagnetic Field Theory in the Presence of Magnetic Sources

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Chinese Physics Letters 2003年第3期20卷 321-324页

作者： Li kang Chen wen-Jun Carlos M. Naón Department of Physics Hangzhou Teacher's College Hangzhou 310036 Department of Physics Zhejiang University Hangzhou 310027 Instituto de Física La Plata Departamento de Física Facultad de Ciencias Exactas Universidad Nacional de La Plata CC 67 1900 La Plata Argentina

Using two new well-defined four-dimensional potential vectors, we formulate the classical Maxwell field theory in a form which has manifest Lorentz covariance and SO(2) duality symmetry in the presence of magnetic sources. We set up a consistent Lagrangian for the theory. Then from the action principle we obtain both Maxwell's equation and the equation of motion of a dyon moving in the electromagnetic field.

关键词： Maxwell equations

Nonparametric Regression with Interval-Censored Data

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Acta Mathematica Sinica,English Series 2014年第8期30卷 1422-1434页

作者： wen Li DENG Zu kang ZHENG Ri Quan ZHANG School of Mathematics and Information Science Jiangxi Normal University Department of Statistics School of ManagementFudan University Department of Statistics School of Finance and StatisticsEast China Normal University

In many medical studies,the prevalence of interval censored data is increasing due to periodic monitoring of the progression status of a *** nonparametric regression model,when the response variable is subjected to interval-censoring,the regression function could not be estimated by traditional methods *** the censored data,we construct a new response variable which has the same conditional expectation as the original *** on the new variable,we get a nearest neighbor estimator of the regression *** is established that the estimator has strong consistency and asymptotic *** relevant simulation reports are given.

关键词： Interval-censored data regression function nearest neighbor estimator

Chemical leaching mechanism of chalcopyrite with difference mineralization

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Rare Metals 2013年第1期32卷 63-66页

作者： Jing Bai Jian-kang wen Song-Tao Huang Biao Wu National Engineering Laboratory of Biohydrometallury General Research Institute for Nonferrous Metals

This paper presents the effect of mineralization on chalcopyrite chemical leaching in very simple H2SO4 solution systems at pH 1.0, with 5 % chalcopyrite con- centrate at 65 ~C. The copper extractions after 12 days leaching of marine volcanic and porphyry chalcopyrite were 85.7 and 66.6 %, respectively. It was found that sulphur element formed on the surface of two samples as a result of XRD and SEM-EDAX, which was very porous that did not inhibit chemical leaching reaction. Meanwhile, （Cu, Fe）12As4S13 formed on the surface of porphyry type chalcopyrite, which may cause low leaching ratio of por- phyry type chalcopyrite as passivation. （Cu, Fe）12As4S13 may be one kind of the polysulphide compounds.

关键词： Chalcopyrite Chemical leaching Passivation Mineralization

Research progress in biohydrometallurgy of rare metals and heavy nonferrous metals with an emphasis on China

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Rare Metals 2016年第6期35卷 433-442页

作者： Jian-kang wen Bo-Wei Chen He Shang Guo-Cheng Zhang National Engineering Laboratory of Biohydrometallurgy General Research Institute for Nonferrous Metals Beijing 100088 China

In the past decade, progress in the field of biohydrometallurgy had been significant. A total of 17 novel biomining microorganisms were discovered, and eight copper heap bioleaching plants and 11 gold biooxidation plants were established or expanded. In this review, it was summarized the physiological properties of the newly isolated biomining microorganisms and three novel microbial ecological methods for studying microbial community dynamics and structure. In addition, biohy- drometallurgy research on rare metals such as uranium, molybdenum, tellurium, germanium, indium, and sec- ondary rare metal resources, as well as heavy nonferrous metals such as copper, nickel, cobalt, and gold has been reviewed, with an emphasis on China. In future, further studies on bioleaching of chalcopyrite, rare metals, secondary resources from waste, and environmental pollution caused by resource utilization are necessary.

关键词： Biohydrometallurgy Microbial ecology Rare metals Practice