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Empilrical Likelihood for Non-parametric Regression Models with Missing Responses:Multiple Design Case

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Acta Mathematicae Applicatae Sinica 2011年第1期27卷 1-12页

作者： Qing-zhu lei Yong-song Qin School of Mathematical Sciences Guangxi Normal University Guilin Guangxi 541004 China

Empirical likelihood （EL） ratio statistic on θ=g（x） is constructed based on the inverse probability weighted imputation approach in a nonparametric regression model Y = g（x）＋ε （x ∈ [0, 1]p） with fixed designs and missing responses, which asymptotically has X1^2 distribution. This result is used to obtain a EL based confidence interval on θ.

关键词： Nonparametric regression empirical likelihood missing at random confidence interval

Influence of river-lake isolation on the water level variations of Caizi Lake, lower reach of the Yangtze River

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Journal of Geographical Sciences 2021年第4期31卷 551-564页

作者： AN Lesheng LIAO Kaihua zhu lei ZHOU Baohua School of Resources and Environment Anqing Normal UniversityAnqing 246133AnhuiChina Key Laboratory of Watershed Geographic Sciences Nanjing Institute of Geography and LimnologyCASNanjing 210008China

In order to explore the water level variations of Caizi Lake under river-lake isolation,the monthly water level of the Chefuling station in Caizi Lake from 1989 to 2018 and the daily water level,rainfall and flow of local hydrological stations in 2018 were analyzed by using the Mann-Kendall trend test and wavelet *** showed that the difference of the average water level of Caizi Lake between the flood and dry seasons was 3.34 m,with a multi-year average water level of 10.42 m above sea *** first and second main periods of the water level of Caizi Lake were 128 and 18 months,respectively,with 4 and 29"up-down"cycles,*** 2018,the next 3-4 years were likely to be the low water level *** water level of Caizi Lake was significantly correlated with that of the Anqing hydrological station of the Yangtze River(r=0.824,P<0.01).In addition,the current hydrological staging of Caizi Lake was about 30 days behind than before the sluice was *** the dual influences of the river-lake isolation and the Yangtze-to-Huaihe Water Diversion Project(YHWD),the hydrological regime change of Caizi Lake and its eco-environmental effect needed long-term monitoring and research.

关键词： water level hydrological regime river-lake isolation wavelet analysis Caizi Lake

Generating labeled samples for hyperspectral image classification using correlation of spectral bands

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Frontiers of Computer Science 2016年第2期10卷 292-301页

作者： Lu YU Jun XIE Songcan CHEN lei zhu Institute of Communications Engineering PLA University of Science and Technology Nanjing 210007 China College of Computer Science and Technology Nanjing University of Aeronautics and Astronautics Nanjing 210016 China College of Command Information System PLA University of Science and Technology Nanjing 210007 China

Because the labor needed to manually label a huge training sample set is usually not available, the problem of hyperspectral image classification often suffers from a lack of labeled training samples. At the same time, hyperspectral data represented in a large number of bands are usually highly correlated. In this paper, to overcome the small sample problem in hyperspectral image classification, correlation of spectral bands is fully utilized to generate multiple new sub-samples from each original sample. The number of labeled training samples is thus increased several times. Experiment results demonstrate that the proposed method has an obvious advantage when the number of labeled samples is small.

关键词： hyperspectral image remote sensing image classification small sample problem

Renewable synthetic fuel:turning carbon dioxide back into fuel

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Frontiers in Energy 2022年第2期16卷 145-149页

作者： Zhen HUANG lei zhu Ang LI Zhan GAO Key Laboratory for Power Machinery and Engineering of the Ministry of Education Shanghai Jiao Tong UniversityShanghai 200240China China Research Institute of Carbon Neutrality Shanghai Jiao Tong UniversityShanghai 200240China

Climate change has emerged as one of the major challenges *** the First Industrial Revolution,the discovery and utilization of fossil energy has promoted the great prosperity and development of human ***,serious issues of environmental and climate change have *** May 2021,CO_(2) concentration in the atmosphere reached 419.13 ppm,observed by the National Oceanic and Atmospheric Administration(NOAA)of US,which arrives at the highest value in human history[1].The CO_(2)-based greenhouse gas emissions lead to global warming,which causes a serious threat to the survival of human being as well as sustainable development of *** September 2020,it was announced that China would scale up its nationally determined contributions and adopt more vigorous policies and activities to peak carbon dioxide emissions before 2030 and achieve carbon neutrality before 2060.

关键词： turning dioxide carbon

A disposable cobalt-based phosphate sensor based on screen printing technology

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Science China Chemistry 2014年第9期57卷 1283-1290页

作者： SONG lei zhu lei LIU YanChen ZHOU XiaoHong SHI HanChang State Key Joint Laboratory of Environmental Simulation and Pollution Control School of EnvironmentTsinghua University Civil Engineering Institute Inner Mongolia University of Technology

Screen printing is a promising technology because of its simplicity, low-cost, high reproducibility, and efficiency in large-scale production. In this work, a cobalt-based phosphate sensor was successfully fabricated using the screen printing technology for the determination of phosphate concentration in the aqueous solution. The disposable sensor consists of a fully integrated cobalt （Co） electrode, which is a layer of carbon conductive ink （C） physically doped with Co powder, and Ag/AgCI reference electrode. The SEM images show that the morphology of the Co electrode changes after exposure to the phosphate solution, indicating that the expendable reaction exists during the measurement. At the Co/C ratio of 1：99, the cobalt-based phosphate sensor shows phosphate-selective potential response in the range of 10-4 to 10-1 mol/L, yielding a detection limit of lxl0-5 mol/L and a slope of over 30 mV/decade in acidic solution （pH 4.5） for HzPO4-. The proposed screen-printed sensor also ex- hibited significant reproducibility with a small repeated sensing deviation （i.e., relative standard deviation （R.S.D.） of 0.5%） on a single sensor and a small electrode-to-electrode deviation （i.e., R.S.D. 〈 3.2%）. The recovery study of HzPO4- in real wastewater samples gave values from 95.4% to 101.8%, confirming its application potential in the measurement of phosphate in real samples. Apart from its high selectivity, sensitivity, and stability comparable with a conventional bulk Co-wire electrode, the proposed phosphate sensor still yields many other advantages, such as low price, compactness, ease of use, and the possibility of integration with other analytical devices such as flow injection analysis.

关键词： phosphate sensor cobalt screen printing potentiometry

Catalyst-controlled regiodivergent 1,2-difunctionalization of alkenes with two carbon-based electrophiles

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Science China Chemistry 2022年第3期65卷 514-520页

作者： Md.Belal Zheqi Li lei zhu Guoyin Yin Institute for Advanced Studies Wuhan UniversityWuhan 430072China Institute of Biomedical Materials Industry Technology Hubei Engineering UniversityWuhan 430074China

Regiodivergent catalysis provides an efficient strategic approach for the construction of architecturally different molecules from the same starting materials. In this field, the intermolecular regiodivergent 1,2-difunctionalization of alkenes with two electrophiles is still a challenging task. A ligand-controlled, nickel-catalyzed regiodivergent dicarbofunctionalization of alkenes using both aryl/vinyl halides and acetals as electrophiles under mild reductive reaction conditions has been accomplished. This study provides a general approach to accessing both β-methoxyl esters and γ-methoxyl esters from readily available acrylates,aryl halides and acetals. Experimental mechanistic evidence supports that the difference in regioselective outcomes is attributed to the ligand tuning the reactivity of the nickel catalyst, which results in different catalytic cycles operating for these two reaction conditions.

关键词： divergent catalysis difunctionalization of alkenes regioselectivity carbon electrophiles nickel catalysis

Formation of Odd Numbered C_(n)^(-)(n>50)Clusters in the Fusion of Fullerenes

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Chinese Physics Letters 1993年第10期10卷 591-593页

作者： zhu lei WANG Slienyi LI Yufen Department of Physics Fudan UniversityShanghai 200433

We observed the phenomena,of fusion of fullerenes by laser desorption of chemical *** R_(n)C_(60)(R=C_(6)H_(5)CH_(2)) in negative ion *** unstable odd numbered C_(n)^(-) clusters(n>50)are readily produced under some experimental conditions,and this can be attributed to tlieir structures possessing cross-section larger than that of the cage-like fiillerencs.

关键词： attributed readily

THE KOLMAR V. SUTEX CASE ON RECIPROCITY IN FOREIGN JUDGMENTS ENFORCEMENT IN CHINA： A WELCOME DEVELOPMENT OR STILL ON THE WRONG TRACK？

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Frontiers of Law in China-Selected Publications from Chinese Universities 2018年第2期13卷 202-217页

作者： zhu lei Lecturer in Law Institute of Intemational Law Wuhan University Wuhan 430072 China EU Competition Law Law School Bangor University Wales

In December 2016, the Nanjing Intermediate People＇s Court in China issued its ruling in the Kolmar vo Sutex case, where a monetary judgment from Singapore was recognized and enforced against a local textile company. The case confirms that once a foreign country has taken the initiative, Chinese courts will follow up to enforce judgments from that country reciprocally. This is the doctrine of de facto reciprocity adopted by some Chinese courts. The paper surveys the judicial practice of Chinese courts and finds that this area of law is full of confusion and uncertainties due to the lack of applicable rules. Recent developments suggest that China may move away from this approach and adopt a relaxed version of reciprocity, which is worthy of close attention.

关键词： recognition and enforcement of foreign judgment reciprocity de facto reciprocity obligation doctrine

A Study of the Molecular Cloud S64 with Multiple Lines of CO Isotopes

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Chinese Journal of Astronomy and Astrophysics 2006年第1期6卷 61-68页

作者： lei zhu Yue-Fang Wu Yue Wei Department of Astronomy Peking University Beijing 100871

We report on a study of the molecular cloud S64 with observations at millimeter wavelengths of multiple molecular lines of CO isotopes. A weak outflow is found, and its physical parameters are estimated. The departure of the core of S64 from the S64 HII region indicates that there are still other star formation activities in that region.

关键词： stars: formation -- ISM: clouds -- ISM: individual: S64 -- ISM: jets and outflows -- ISM: evolution -- ISM: kinematics and dynamics