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Two-Stage Point Cloud Super Resolution with Local Interpolation and Readjustment via Outer-Product Neural Network

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Journal of Systems Science & Complexity 2021年第1期34卷 68-82页

作者： wang guangyu XU Gang WU Qing WU Xundong School of Computer Science and Technology Hangzhou Dianzi UniversityHangzhou 310018China Key Laboratory of Complex Systems Modeling and Simulation Ministry of EducationHangzhou 310018China

This paper proposes a two-stage point cloud super resolution framework that combines local interpolation and deep neural network based readjustment. For the first stage, the authors apply a local interpolation method to increase the density and uniformity of the target point cloud. For the second stage, the authors employ an outer-product neural network to readjust the position of points that are inserted at the first stage. Comparison examples are given to demonstrate that the proposed framework achieves a better accuracy than existing state-of-art approaches, such as PU-Net, Point Net and DGCNN(Source code is available at https://***/qwerty1319/PC-SR).

关键词： Neural network outer-product network point cloud super resolution

Impacts of COVID-19 on tourism and management response from Banff National Park,Canada

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Journal of Forestry Research 2023年第5期34卷 1229-1244页

作者： Christina Dehui Geng Howie WHarshaw Wanli Wu guangyu wang Department of Forest Resources Management Faculty of ForestryUniversity of British ColumbiaVancouverCanada Faculty of Kinesiology Sportand RecreationUniversity of AlbertaEdmontonCanada

The COVID-19 pandemic posed challenges to the tourism sector *** investigated changes in visitor demographics,satisfaction level,and its determinants pre-and *** were collected using questionnaire surveys in 2019 and 2021 within Banff National Park(BNP).The data analyses were based on a sample size of 1183 respondents by conducting factor analysis,correlation analysis and stepwise regression *** highlight that there were fewer international visitors and more local and domestic visitors during the *** attributes were evaluated at a higher satisfaction level *** quality of the Park facilities and services were the most important satisfaction determinants pre-and peri-COVID-19,and all the Park COVID-19 measures and actions received positive experience from *** research fills this knowledge gap by developing a better understanding in the change of visitor demographics and satisfaction level in BNP under the context of the *** also provides implication for both scholars and practitioners to understand the impacts of the pandemic on Park *** study can provide insights for utilizing the pandemic as a transformative strength and for mitigating its negative impact on tourism industry.

关键词： National park COVID-19 pandemic Visitor experience Tourism management Visitor perception

Bimetallic Pd-Cu/Al_(2)O_(3) Catalyst for the Green Catalytic Synthesis of 2,2'-bipyridine from Pyridine

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Journal of Wuhan University of Technology(Materials Science) 2022年第6期37卷 1123-1128页

作者： wang Lin ZHANG Yimeng wang guangyu FENG Yisi LI Qianwen College of Light-Textile Engineering and Art Anhui Agriculture UniversityHefei 230036China School of Chemistry and Chemical Engineering Hefei University of TechnologyHefei 230009China Wuhu Youpai Nursing Products Technology Co. LtdWuhu 241000China

Bimetallic Pd-Cu/Al_(2)O_(3) was prepared by wetness impregnation method and its catalytic activity on coupling reaction of pyridine to 2,2'-bipyridine was assessed in view of the effects of different molar ratios of Pd:*** is found that Pd-Cu/Al_(2)O_(3) has the small particle size and good dispersion through the *** with Pd/Al_(2)O_(3),Pd-Cu(1:2)/Al_(2)O_(3) is the preferable catalyst under the optimum conditions of 1 MPa N2 pressure,310℃and 16 *** conversion of pyridine is 35.4%,and the selectivity for 2,2'-Bipyridine is up to 99%,which is much higher activity than Pd/Al_(2)O_(3).The directly coupled synthesis meets the requirements of the atomic economy *** addition of Cu also reduces the dosage of Pd and lowers the *** is worth noting that the recycled Pd-Cu/Al_(2)O_(3) catalyst still shows high activity and stability after three times.

关键词： Pd-Cu/Al_(2)O_(3) X-ray diffraction atomic economy 2,2'-bipyridine catalytic activity

Moisture content thresholds for ignition and rate of fire spread for various dead fuels in northeast forest ecosystems of China

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Journal of Forestry Research 2021年第3期32卷 1147-1155页

作者： Maombi Mbusa Masinda Long Sun guangyu wang Tongxin Hu Key Laboratory of Sustainable Forest Ecosystem Management-Ministry of Education College of ForestryNortheast Forestry University26 Hexing RoadHarbin 150040People’s Republic of China Faculty of Sciences UniversitéOffi cielle de RuwenzoriPO Box 560ButemboNorth KivuDemocratic Republic of the Congo Heilongjiang Vocational Institute Ecological Engineering HarbinHeilongjiang ProvincePeople’s Republic of China

Fuel moisture content is one of the important factors that determine ignition probability and fire behaviour in forest *** this study,ignition and fire spread moisture content thresholds of 40 dead fuel were performed in laboratory experiments,with a focus on the source of ignition and wind *** in fuel moisture content at time of ignition and during fire spread was observed for different *** were more efficient to result in ignition and spread fire with high values of fuel moisture content compared to the use of cigarette *** fuels did not ignite at 15%moisture content,whereas others ignited at 40%moisture content and fire spread at 38%moisture content in the case of matches,or ignited at 27%moisture content and spread fire at 25%moisture content using cigarette butts.A two-way ANOVA showed that both the source of ignition and the wind speed affected ignition and fire spread threshold significantly,but there was no interaction between these *** relationship between ignition and fire spread was strong,with R2=98%for cigarette butts,and 92%for *** information is needed,especially on the density of fuels,fuel proportion(case of mixed fuels),fuel age,and fuel combustibility.

关键词： Dead fuel Ignition source Wind speed Ignition moisture threshold Propagation moisture threshold

Dynamics of major air pollutants from crop residue burning in China's Mainland,2000–2014

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Journal of Environmental Sciences 2018年第8期30卷 190-205页

作者： Quanfeng Jin Xiangqing Ma guangyu wang Xiajie Yang Futao Guo College of Forestry Fujian Agriculture and Forestry UniversityFuzhou 350002China Co-innovation Center for Soil and Water Conservation in the Red Soil Region of the Cross-straits Fuzhou 350002China Li Shui Vocational Technical College Lishui 323000China Asia-Pacific Forest Research Centre Faculty of ForestryUniversity of British ColumbiaVancouverBC V6T 1Z4Canada

Based on satellite image data and China＇s Statistical Yearbooks（2000 to 2014）, we estimated the total mass of crop residue burned, and the proportion of residue burned in the field *** as domestic fuel. The total emissions of various pollutants from the burning of crop residue were estimated for 2000-2014 using the emission factor method. The results indicate that the total amount of crop residue and average burned mass were 8690.9 Tg and4914.6 Tg, respectively. The total amount of emitted pollutants including CO2, CO, NOx,VOCs, PM（2.5）, OC（organic carbon）, EC（element carbon） and TC（total carbon） were 4212.4–8440.9 Tg, 192.8–579.4 Tg, 4.8–19.4 Tg, 18.6–61.3 Tg, 18.8–49.7 Tg, 6.7–31.3 Tg, 2.3–4.7 Tg, and8.5–34.1 Tg, respectively. The emissions of pollutants released from crop residue burning were found to be spatially variable, with the burning of crop residue mainly occurring in Northeast, North and South China. In addition, pollutant emissions per unit area（10 km ×10 km） were mostly concentrated in the central and eastern regions of China. Emissions of CO2, NOx, VOCs, OC and TC were mainly from rice straw burning, while burning of corn and wheat residues contributed most to emissions of CO, PM（2.5） and EC. The increased ratio of PM（2.5） emissions from crop residue burning to the total emitted from industry during the study period is attributed to the implementation of strict emissions management policies in Chinese industry. This study also provides baseline data for assessment of the regional atmospheric environment.

关键词： Agricultural pollutants Crop residue Straw burning Air pollution Temporal and spatial variations

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

Tomography system for measurement of gas properties in combustion flow field

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Chinese Journal of Aeronautics 2017年第5期30卷 1697-1707页

作者： Junling SONG Yanji HONG Mingyuan XIN guangyu wang Zhaoran LIU State Key Laboratory of Laser Propulsion & Application Space Engineering University Beijing 101416 China Science and Technology on Scramjet Laboratory Hypervelocity Aerodynamics Institute CARDC Mianyang 621000 China

This paper describes a self-designed fiber-coupled tomography system and its application in combustion diagnostics. The tomographic technique, which combines tunable diode laser spectroscopy and algebraic reconstruction technique, enables the simultaneous reconstruction of temperature and gas concentration with both spatial and temporal resolutions. The system measures a maximum diameter of 35 cm in a circular area with a minimum spatial resolution of 1 mm×1 mm and temporal response of up to 1 kHz. Simulations validate the effects of the beam arrangement and discrete grid on reconstruction accuracy, and give the optimal beam arrangements. Experiments are made to demonstrate the tomography method, and systems are constructed in laboratory and on engineering test benches.

关键词： Absorption Combustion diagnostics Spectroscopy Temperature Tomographic image

Neutral Five-Coordinate Arylated Copper(Ⅲ) Complex: Key Intermediate in Copper-Mediated Arene Trifluoromethylation

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Chinese Journal of Chemistry 2022年第16期40卷 1924-1930页

作者： guangyu wang Man Li Xuebing Leng Xiaosong Xue Qilong Shen Key Laboratory of Organofluorine Chemistry Shanghai Institute of Organic ChemistryUniversity of Chinese Academy of SciencesChinese Academy of Sciences345 Lingling LuShanghai200032 China Key Laboratory of Material Chemistry for Energy Conversion and Storage Ministry of EducationHubei Key Laboratory of Bioinorganic Chemistry and Materia MedicaHubei Key Laboratory of Materials Chemistry and Service FailureSchool of Chemistry and Chemical EngineeringHuazhong Universityof Scienceand TechnologyWuhanHubei 430074China

Five-coordinate neutral Cu(Ⅲ)complexes have long been considered as the key intermediates in copper-mediated/catalyzed arene trifluoromethylative reactions,but the identity of these complexes remains ***,we reported,for the first time,the preparation and characterization of these putative complexes[(bpy)Cu(CF_(3))_(2)(C_(6)F_(4)R)]and investigation of their C(sp^(2))-CF_(3) bond-forming reductive *** mechanistic studies including kinetic studies,the effect of temperature and solvents,the effect of the para-substitution of the ligand as well as DFT calculations suggest that C(sp^(2))-CF_(3) reductive elimination process proceeds via synchronous bond-breaking/bond-forming process.

关键词： Cu(Ⅲ) Reductive elimination Trifluoromethyl Mechanism Concerted pathway

Cow milkα_(s1)-casein induces allergic responses in a mouse model of atopy

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Food Science and Human Wellness 2022年第5期11卷 1282-1289页

作者： guangyu wang Xiaofeng Yu Yanjun Cong Linfeng Li Beijing Higher Institution Engineering Research Center of Food Additives and Ingredients College of Food and HealthBeijing Technology and Business UniversityBeijing 100048China Department of Dermatology Beijing Friendship HospitalBeijing 100050China

α_(s1)-Casein is a potential allergen to induce hypersensitivity in cow *** had identifiedα_(s1)-casein and its epitopes in previous *** present study aimed to evaluate the allergic mechanism ofα_(s1)-casein in a BALB/c mouse *** levels of specific IgE,mast cell proteinase,histamine and cytokines in sensitized mice were determined,and the clinical and pathological observation were *** showed that the levels of specific IgE,mast cell proteinase,histamine,IL-4,IL-5,IL-10 increased significantly with a dose-dependent *** local alveolar septum collapsed or thickened,and lymphatic foci were produced in the spleen and thymus,and the inflammatory cells infiltrated in small intestinal mucosa *** conclusion,the levels of specific IgE,mast cell proteinase,histamine,IL-4,IL-5,IL-10 and some inflammatory factors could possibly serve as allergic biomarkers ofα_(s1)-casein,however,additional studies on signal transduction and gene expression are necessary in future.

关键词： Cow milk α_(s1)-Casein Allergen BALB/c mouse model Allergic mechanism