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Plant Diseases and Pests 2010年第2期1卷 32-34页

作者：张丽莲杨林楠杨仕生云南农业大学基础与信息工程学院云南昆明650201 云南省建水县植保站云南建水654300

[Objective] The research aimed to study the significant influence factors of the population variations of oriental fruit fly. [Method] Using stepwise regression analysis, the population variations law of oriental fruit fly in Jianshui County of Yunnan province and the meteorological factors that caused its occurrence were analyzed. And the regression model was built. Finally, the regression model was tested on the basis of the data in Jianshui County of Yunnan Province during 2004-2006.[Result] The main meteorological factors that influenced the occurrence of oriental fruit fly were relative humidity, the lowest monthly temperature and rainfall. [Conclusion] This study will provide certain reference for the prediction researches on the time, quantity and occurrence peak of oriental fruit fly.

关键词： Oriental fruit fly stepwise regression analysis Meteorological factors

Effect of Complex Parameters of Porous Media on Desalination Performance in Air-Gap Diffusion Distillation Based on Multiple regression analysis

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Journal of Thermal Science 2022年第6期31卷 2329-2345页

作者： CHEN Lele WANG Ping ZHANG Xuan QIU Qinggang Key Laboratory of Ocean Energy Utilization and Energy Conservation of Ministry of Education School of Energy and Power EngineeringDalian University of TechnologyDalian 116024China

Air-Gap Diffusion Distillation(AGDD) is a new technology aiming at solving the problem of the safety of drinking water for residents in remote areas that uses a super hydrophilic porous medium as the hot channel and evaporation surface. In the experiment, it was found that the parameters of porous media have a significant influence on the desalination(evaporation) efficiency of AGDD. Although porous media are widely used as evaporation components, the factors affecting their evaporation efficiency are not fully understood. The evaporation process in super hydrophilic porous media is rarely discussed. A large number of experiments have been carried out based on AGDD. The introduction of statistical methods solves the problem that experiments cannot distinguish the contribution of complex parameters of porous media to evaporation efficiency. stepwise regression analysis is used to reduce the dimensionality of the independent variables and construct regression equations(coefficient of determination R~2 reached 81.3%-96.8%). Evaporation flux correlations and dimensionless mass transfer correlations are established based on porous media parameters. We found that the surface evaporation of super hydrophilic porous media can be divided into three stages: diffusion evaporation, capillary evaporation, and thermal evaporation. The evaporation efficiency of these three stages is controlled by the vapor diffusion process resistance, capillary force, and energy supply. At low saturation, evaporation efficiency is limited by the resistance of the vapor diffusion process. The evaporation efficiency of the porous media is affected predominantly by the pore size, the specific surface area, porosity and the characteristic length. At high saturation, the evaporation efficiency becomes influenced primarily by the permeability. A small thickness and a high hydrophilicity also improve the evaporation efficiency.

关键词： Air-Gap Diffusion Distillation(AGDD) stepwise regression analysis evaporation super hydrophilic porous media desalination

Photodegradation of methylmercury in the water body of the Three Gorges Reservoir

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Science China Chemistry 2015年第6期58卷 1073-1081页

作者： Rongguo Sun Dingyong Wang Wen Mao Shibo Zhao Cheng Zhang Xiang Zhang Chongqing Key Laboratory of Soil Multiscale Interfacial Process College of Resource and Environment Southwest University School of Chemistry and Material Guizhou Normal University Chongqing Key Laboratory of Agricultural Resources and Environment

Biogeochemical cycling of mercury in the young Three Gorges Reservoir （TGR）, China, is strongly considered. Although methylmercury （MMHg） photodegradation （PD） is an important process involved in mercury cycling in this zone, little is known about this process. In situ incubation experiments were therefore performed to quantify the effect of different wave- length radiations and environmental factors on the PD process of MMHg in the water bodies of TGR. It was found that the ef- fect of solar radiation on MMHg PD was highly dependent on wavelength and water depth. All PD-rate constants resulting from each wavelength range decreased rapidly with water depth. For surface water, UV-A radiation （320-400 nm） was the key driver, accounting for 49%-62% of MMHg PD. For the entire water column, both photosynthetically active radiation （PAR, 400-700 nm） and UV-A were responsible for MMHg PD. MMHg PD fluxes peaked in summer （7.5-18 ng m-2 d-1）, followed by spring （3.3-8.0 ng m-2 d-1）, autumn （1.0-2.7 ng m-2 d-1）, and winter （0.060-0.15 ng m-2 d-1）. The annual fluxes of MMHg PD were estimated to be 1.1-2.8 μg m-2 at. Filtering the reservoir water and amending it with chemicals （i.e., CV, NO C, and dissolved organic matter （DOM）） showed significant effects on MMHg PD rate constants. stepwise regression analysis showed that intensity of solar radiation, suspended particulate matter （SPM）, DOM, CI-, and NO3- were involved in the PD process. Path analysis clarified the relationship between MMHg PD rate constants and environmental variables, as well as the comparative strength of direct and indirect relationships among variables. The results are of great importance for understanding MMHg cycling characteristics in TGR and also facilitate the understanding of the underlying process, MMHg PD, in natural waters.

关键词： methylmercury photodegradation influencing factor stepwise regression analysis path analysis Three GorgesReservoir

QSAR Studies on 6-(1-Naphthylmethyl) Substituted S-DABO Derivatives as Novel Non-nucleoside HIV-1 Reverse Transcriptase Inhibitors

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Chinese Journal of Structural Chemistry 2008年第10期27卷 1214-1222页

作者：殷丽琴余仕问姚凌峰何严萍谢小光 Department of Chemistry Yunnan University Key Laboratory of Medicinal Chemistry for Natural Resource(Yunnan University) Ministry of Education

The AM1 and B3LYP methods were employed to calculate the structural properties of 20 6-（1-naphthylmethyl） substituted S-DABO derivatives with β-carbonyl group on the C（2） side chain as novel potent non-nucleoside HIV-1 reverse transcriptase inhibitors. The correlation analysis （CA） and stepwise multiple regression analysis （SMR） were performed. The QSAR models indicate that the physicochemical parameters of Qc9, MRR1, ELUMO, ∏R2 and μ have significant influence on the activities of these derivatives. The substitution of hydrophobic R2 and bulky aromatic R1 to form a conjugated system with the frame of those S-DABO series compounds should be considered to design new potent compounds for anti-HIV-1.

关键词： S-DABO derivatives correlation analysis stepwise regression analysis QSAR LUMO

Impacts of COVID-19 pandemic on urban park visitation:a global analysis

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Journal of Forestry Research 2021年第2期32卷 553-567页

作者： Dehui(Christina)Geng John Innes Wanli Wu Guangyu Wang Faculty of Forestry University of British Columbia2424 Main MallVancouverBC V6T 1Z4Canada

The COVID-19 pandemic has resulted in over 33 million confirmed cases and over 1 million deaths globally,as of 1 October *** the lockdown and restrictions placed on public activities and gatherings,green spaces have become one of the only sources of resilience amidst the coronavirus pandemic,in part because of their positive effects on psychological,physical and social cohesion and spiritual *** study analyzes the impacts of COVID-19 and government response policies to the pandemic on park visitation at global,regional and national levels and assesses the importance of parks during this global *** data we collected primarily from Google’s Community Mobility Reports and the Oxford Coronavirus Government Response *** results for most countries included in the analysis show that park visitation has increased since February 16th,2020 compared to visitor numbers prior to the COVID-19 *** on social gathering,movement,and the closure of workplace and indoor recreational places,are correlated with more visits to ***-at-home restrictions and government stringency index are negatively associated with park visits at a global *** from residents for parks and outdoor green spaces has increased since the outbreak began,and highlights the important role and benefits provided by parks,especially urban and community parks,under the COVID-19 *** provide recommendations for park managers and other decision-makers in terms of park management and planning during health crises,as well as for park design and *** particular,parks could be utilized during pandemics to increase the physical and mental health and social well-being of individuals.

关键词： COVID-19 COVID-19 response policies Parks visitation stepwise regression analysis Urban parks

Spectral Features of Soil Organic Matter

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Geo-Spatial Information Science 2009年第1期12卷 33-40页

作者： HE Ting WANG Jing LIN Zongjian CHENG Ye Key Laboratory of Land Use Ministry of Land and Resources 37 Guanyin~uanxiqu Xicheng District Beijing lO0035China.

The study on soil spectral reflectance features is the physical basis for soil remote sensing. Soil organic matter content influences the soil spectral reflectance dramatically. This paper studied the spectral curves between 400 nm-2500 nm of 174 soil samples which were collected in Hengshan county and Yixing county. Fourteen types of transformations were applied to the soil reflectance R to remove the noise and to linearize the correlation between reflectance （independent vari- able） and soil organic matter （SOM） content （dependent variable）. Then, the methods such as derivative spectrum technology and stepwise regression analysis, were applied to study the relationship between these soil spectral features and soil organic matter content. It shows that order 1 derivative of the logarithm of reflectance （01DLA） is the most sensitive to SOM among the various transform types of reflectance in consideration. The regression model whose coefficient of determination reaches 0.885 is built. It predicted the soil organic matter content with higher effect.

关键词： soil organic matter (SOM) spectral features stepwise regression analysis

Experiences of Fatigue at Sea—A Comparative Study in European and Chinese Shipping Industry

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Journal of Biosciences and Medicines 2016年第3期4卷 65-68页

作者： Zhiwei Zhao Jorgen Riis Jepsen Zhonglong Chen Huanxin Wang Seafarers Development International Research Centre Dalian Maritime University Dalian China Centre of Maritime Health and Society University of Southern Denmark Odense Denmark

Fatigue has negative impacts on the general working population as well as on seafarers. In order to study seafarers’ fatigue, a questionnaire-base survey was conducted to gain information about potential risk factors for fatigue and construct indexes indicating fatigue. The study applies T-test to compare strata of seafarers to analyse work and sleep patterns in global seafaring. Qualitative analysis are also employed to explore the impacts of fatigue on seafarer’s occupational health and safety.

关键词： Fatigue Seafarers Work and Sleep Patterns T-Test stepwise regression analysis

Experimental Investigation on Individual Effect of Deformation Variables on Mechanical Behavior of Superplastic Alloy Zn-Al

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东北大学学报(自然科学版) 1984年第2期 154-158页

作者： Wang Zhenfan, Chen Jiamin and Ma Longxiang

Quite a good deal of research works on the effect of deformation variables, i. e. the deformation temperature T, strain e and strain rate ε etc, on the mechanical behavior of superplastic materials have already been done, but these variables are non-separated on each other even are regarded as unable to be thoroughly separated in measurement so far. Based on experiments for the superplastic alloy Zn-20Al, this paper is written with an attempt to separate deformation variables by introducing a method of stepwise regression analysis into test results according to the mechanical model in form σ=K εmεneA/T, and to determine further the relationship among the straion-rate sensitivity index m, hardenability index n and constant K,

关键词： Zn Al superplastic alloy deformation variables stepwise regression analysis strain-rate sensitivity index activation factor.

Rural Poverty Patterns and Influencing Factors in Yunnan Province,China:Based on County Level Dataset

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Journal of Resources and Ecology 2020年第4期11卷 366-377页

作者： SHANG Xiaowen CHEN Yufu Institute of Geographic Sciences and Nature Resources Research Chinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China

The identification of poverty at the county level is the precondition for poverty alleviation by formulating accurate strategies that are targeted for a certain *** Province has the largest number of poverty counties in *** vast number of people living under the poverty-line,and the deep degree of poverty across a wide distribution range,pose major *** on the rural poverty incidence data,this paper describes the rural poverty patterns in Yunnan Province in 2010 and 2015,and then it explores the main factors which influence the incidence and changes in rural poverty at the county level in Yunnan Province using a stepwise regression analysis *** study found that the rural poverty in counties of Yunnan Province was deeply affected by natural conditions and the geographical *** 2010 and 2015,the rural poverty situation in the middle region of Yunnan Province was relatively light,while it was more serious in the northwest,northeast and south *** pattern of county poverty is in good agreement with the topography and landforms of Yunnan Province and the poverty-stricken *** are strong correlations between the incidence of rural poverty in Yunnan Province with both the annual per capita net income of rural residents and the degree of agricultural *** factors are related to the living standards and agricultural production necessary for the peasantry to sustain their *** change in the incidence of rural poverty at the county level in Yunnan Province from 2010 to 2015 is significantly correlated with changes in the value-added of the primary industries and the degree of agricultural *** correlations indicate that the development of primary industry plays a key role in the process of lifting rural residents in Yunnan Province out of poverty so they can achieve ***,improving the annual per capita net income of rural residents and the degree of agricultural me

关键词： rural poverty poverty incidence stepwise regression analysis Yunnan Province

Optimal Models for Impact of Agricultural Machinery System on Agricultural Production in Heilongjiang Agricultural Reclamation Area

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Optimal Models for Impact of Agricultural Machinery System o...