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Formation of Small Bottle Light Beams

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Chinese Physics Letters 2007年第12期24卷 3412-3415页

作者：饶连周蒲继雄 Department of Physics and Electromechanical Engineering Sanming University Sanming 365004 Department of Electronic Science and Technology Huaqiao University Quanzhou 362021

A method for obtaining small bottle light beams, e.g. 0.92λ×0.4λ, in a high numerical-aperture lens system is proposed and numerically demonstrated. This can be achieved by changing the radius of each zone of the binary element and polarization rotation angle of the cylindrically polarized vectorial vortex beam. It is found that the transversal and axial sizes of this bottle beam are equal to about 0.92λ and 0.4λ, respectively. In addition, the connection between angular momentum and topological Pancharatnam charge is also shown.

关键词： thermoelectric half-Heusler compounds thermal conductivity

Impact of Climate Comfort on Tourism in Putian City and Countermeasures

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Journal of Geoscience and Environment Protection 2018年第9期6卷 157-169页

作者： Zheng Xiao Huqing He Gang Li Decai Tang Putian City Xiuyu District meteorological bureau Putian China Nanjing University of Information Science and Technology Nanjing China

Putian is an emerging tourist city in fujian province. It not only has Weizhou Island, the birthplace of the world’s Mazu culture, but also the national 4A scenic spot, like Jiuyi Lake, Jiulong Valley, South Shaolin, etc., attracting thousands of tourists every year. This paper uses meteorological data of the Putian Municipal meteorological bureau from 1988 to 2017, negative oxygen ion data in the scenic spots of Weizhou Island, Jiuyi Lake and Jiulong Valley from 2014 to 2017 and monthly data of tourists from 2011 to 2017 provided by Putian City Tourism bureau. Based on the Temperature and Humidity Index, the Wind Cold Index, the Index of Cloth Loading and the Air Comfort Index, this paper uses the analytic hierarchy process (AHP) to construct a new comprehensive climate comfort model. Using the new model, the climate comfort index of Putian is calculated, and the levels and time periods suitable for tourism are divided. The number of tourists in Putian City is increasing year by year and has obvious time distribution characteristics. There are two peak periods in which tourists are concentrated in each year, which are April to May and October to November, belonging to the spring-autumn type. This paper also uses Ordinary Least Square (OLS) regression method to analyze the climate comfort and tourist traffic. The results show that there is a clear correlation between the comfort index and the passenger flow. Accordingly, suggestions for improvement of tourism development in Putian are proposed.

关键词： Putian Climate Comfort Analytic Hierarchy Process Passenger Flow

Application of Improved Matter-element Extension Method in Comprehensive Assessment of Shallow Groundwater

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Journal of Landscape Research 2016年第4期8卷 16-20,26页

作者： HUANG Yaoyi SU Jianyun CHEN Wencheng College of Resources and Environment Science Quanzhou Normal University

Taking shallow groundwater in Jinjiang City,fujian province for example,it was found that the classical element-matter analysis shows deficiency in calculation of correlation function,so the improved matter-element method was applied for the comprehensive assessment of shallow groundwater in Jinjiang City,and the spatial distribution was shown in *** assessment results demonstrated that ground water quality of most regions in the study area belonged to Grade I and II,thus the overall quality of shallow groundwater was *** groundwater of Grade IV and V(relatively poor and extremely poor) was mainly distributed in Dongshi Town,Chendi Town,Zimao Town,and Shenhu Town,major exceeding-standard factors that influence shallow groundwater quality in the local area included TDS,Mn^(2+),NO_3,NO_2,NH_4^+ and Cl^-,which mainly owed to invasion of seawater,original geological conditions,industrial and agricultural discharge,and human life.

关键词： Improved matter-element analysis Correlation degree Shallow groundwater Comprehensive assessment

Evaluation of ERA-Interim Monthly Temperature Data over the Tibetan Plateau

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Journal of Mountain Science 2014年第5期11卷 1154-1168页

作者： GAO Lu HAO Lu CHEN Xing-wei College of Geographical Sciences Fujian Normal University fujian Provincial Engineering Research Center for Monitoring and Assessing Terrestrial Disasters Research Center for National Geographical Condition Monitoring and Emergency Support in the Economic Zone on the West Side of the Taiwan Strait College of Applied Meteorology Nanjing University of Information Science & Technology

In this study, surface air temperature from 75 meteorological stations above 3000 m on the Tibetan Plateau are applied for evaluation of the European Centre for Medium-Range Weather Forecasts(ECMWF) third-generation reanalysis product ERA-Interim in the period of 1979-2010. High correlations ranging from 0.973 to 0.999 indicate that ERA-Interim could capture the annual cycle very well. However, an average root-meansquare error(rmse) of 3.7°C for all stations reveals that ERA-Interim could not be applied directly for the individual sites. The biases can be mainly attributed to the altitude differences between ERA-Interim grid points and stations. An elevation correction method based on monthly lapse rates is limited to reduce the bias for all stations. Generally, ERA-Interim captured the Plateau-Wide annual and seasonal climatologies very well. The spatial variance is highly related to the topographic features of the TP. The temperature increases significantly(10°C- 15°C) from the western to the eastern Tibetan Plateau for all seasons, in particular during winter and summer. A significant warming trend(0.49°C/decade) is found over the entire Tibetan Plateau using station time series from 1979-2010. ERA-Interim captures the annual warming trend with an increase rate of 0.33°C /decade very well. The observation data and ERA-Interim data both showed the largest warming trends in winter with values of 0.67°C/decade and 0.41°C/decade, respectively. We conclude that in general ERA-Interim captures the temperature trends very well and ERA-Interim is reliable for climate change investigation over the Tibetan Plateau under the premise of cautious interpretation.

关键词： Reanalysis Air temperature Warming trend Tibetan Plateau

Channel attention based wavelet cascaded network for image super-resolution

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High Technology Letters 2022年第2期28卷 197-207页

作者： CHEN Jian HUANG Detian HUANG Weiqin College of Engineering Huaqiao UniversityQuanzhou 362021P.R.China School of Information Science and Technology Xiamen University Tan Kah Kee CollegeZhangzhou 363105P R.China

Convolutional neural networks(CNNs) have shown great potential for image super-resolution(SR).However,most existing CNNs only reconstruct images in the spatial domain,resulting in insufficient high-frequency details of reconstructed *** address this issue,a channel attention based wavelet cascaded network for image super-resolution(CWSR) is ***,a second-order channel attention(SOCA) mechanism is incorporated into the network,and the covariance matrix normalization is utilized to explore interdependencies between channel-wise ***,to boost the quality of residual features,the non-local module is adopted to further improve the global information integration ability of the ***,taking the image loss in the spatial and wavelet domains into account,a dual-constrained loss function is proposed to optimize the *** results illustrate that CWSR outperforms several state-of-the-art methods in terms of both visual quality and quantitative metrics.

关键词： image super-resolution(SR) wavelet transform convolutional neural network(CNN) second-order channel attention(SOCA) non-local self-similarity

Application of Improved SPA Method in the Comprehensive Assessment of Groundwater Environment Quality:A Case Study of Jinjiang, fujian province

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Journal of Landscape Research 2016年第1期8卷 73-75,79页

作者： SU Jianyun HUANG Yaoyi LI Bin School of Resources and Environment Science Quanzhou Normal University Urban and Rural Planning and Resource Recycling Environmental Engineering Experiment Center Quanzhou Normal University

This paper applied the set pair analysis with improved five-element connection degree to assess shallow groundwater quality of Jinjiang City, fujian province, and used map to show the spatial distribution. The assessment results showed that most groundwater in the district was in the grade I and II, i.e. the overall groundwater environment in this area was favorable; groundwater of grade III(poorer level) was mainly distributed in Dongshi Town in the coastal region, and the total area was smaller. Major out-of-limit factors are TDS, nitrate, nitrite, ammonia nitrogen, and chloride, therefore, industrial and agricultural development, human activities and seawater invasion were major causes for the aggravation of water quality.

关键词： Improved set pair analysis Five-element connection degree Groundwater Comprehensive assessment

Fault Ride-Through(FRT)Behavior in VSC-HVDC as Key Enabler of Transmission Systems Using SCADA Viewer Software

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Energy Engineering 2022年第6期119卷 2369-2406页

作者： Samuel Bimenyimana Chen Wang Godwin Norense Osarumwense Asemota Aphrodis Nduwamungu Francis Mulolani Jean De Dieu Niyonteze Shilpi Bora Chun-Ling Ho Noel Hagumimana Theobald Habineza Waqar Bashir Yiyi Mo Intelligence and Automation in Construction Provincial Higher-Educational Engineering Research Centre Huaqiao UniversityXiamen361021China African Centre of Excellence in Energy for Sustainable Development University of RwandaKigali4285Rwanda fujian province Key Laboratory of Automotive Electronics and Electric Drive Fujian University of TechnologyFuzhou350118China Department of Climate Change Observatory Secretariat Ministry of EducationKigali4285Rwanda School of Electrical Engineering and Automation Tianjin Polytechnic UniversityTianjin300000China Department of Electrical and Electronics Engineering Copperbelt UniversityKitwe23456Zambia Ajeenkya D Y PatilUniversity LohegaonPune412105India Carnegie Mellon University-Kigali Rwanda Campus Kigali4285Rwanda

The world’s energy consumption and power generation demand will continue to ***,the bulk of the energy resources needed to satisfy the rising demand is far from the load *** aforementioned requires long-distance transmission systems and one way to accomplish this is to use high voltage direct current(HVDC)transmission *** main technical issues for HVDC transmission systems are loss of synchronism,variation of quadrature currents,amplitude,the inability of station 1(rectifier),and station 2(inverter)to either inject,or absorb active,or reactive power in the network in any circumstances(before a fault occurs,during having a fault in network and after a fault cleared),and the variations of power transfer ***,faults impact power quality such as voltage dips and power line outage *** paper presents a method of overcoming the aforementioned technical issues using voltage-source converter(VSC)based HVDC transmission systems with SCADA VIEWER software and dynamic grid *** benefits include having a higher capacity transmission system and proposed best method for control of active and reactive power transfer *** results obtained using MATLAB validated the experimental results from SCADA Viewer *** results indicate that the station’s rectifier or inverter can either inject or absorb either active power or reactive power in any ***,the reverse power flow under different modes of operation can ride through *** a 100.0%power transfer rate,the rectifier injected 775.0 W into the *** a 0.0%power transfer rate,the rectifier injected 164.0 W into the *** a-100.0%rated power,the rectifier injected 1264.0 W into the network and direction was also changed.

关键词： Fault ride through capability dynamic grid fault simulator asymmetric components negative sequence control

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