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A MULTI-WINDOW GIS APPROACH FOR WATER QUALITY DATA ANALYSIS
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作者 Lin Hui(Department of Geography,The Chinese University of Hong Kong,Shatin,New Territory,Hong Kong)Xia Fuxiang(NCGIA and Great Lakes Program, State University of New York at Buffalo,Buffalo, NY 14260, USA) 《Chinese Geographical Science》 SCIE CSCD 1995年第3期257-264,共8页
For many water quality studies,a data analyst,or modeler, may need to know the spatio-temproal patterns of the data sets and their relationships in both pre-processing and post-processing. Geographic Information Syste... For many water quality studies,a data analyst,or modeler, may need to know the spatio-temproal patterns of the data sets and their relationships in both pre-processing and post-processing. Geographic Information System(GIS) can provide an exploratory spat 展开更多
关键词 GEOGRAPHIC INFORMATION System MULTI-window approach water QUALITY analysis
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Windows环境下光伏水泵报价系统的实现
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作者 茆美琴 何慧若 《合肥工业大学学报(自然科学版)》 CAS CSCD 1996年第3期99-103,共5页
该文介绍了在Windowe3.1环境下.利用MicrosoftC(++)及其基本类库(MFC)开发光伏水泵报价系统的方法。该方法采用了面向对象技术,使软件具备可重用性。同时,MFC类库的使用使复杂的Win-dows应... 该文介绍了在Windowe3.1环境下.利用MicrosoftC(++)及其基本类库(MFC)开发光伏水泵报价系统的方法。该方法采用了面向对象技术,使软件具备可重用性。同时,MFC类库的使用使复杂的Win-dows应用程序的编程接口变得更容易。该方法对其它工程报价问题也具借鉴意义。 展开更多
关键词 光伏水泵系统 配置 报价软件 Winodws3.1
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滑动窗口式三维watershed算法实现视频序列分割
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作者 石荣 傅志中 +1 位作者 李晓峰 李在铭 《信号处理》 CSCD 2004年第2期192-196,共5页
视频序列分割是实现视频对象提取、处理和识别的基础,也是基于内容的视频压缩和检索的前提。目前普遍采用的watershed算法是全局涨水算法,用于视频分割时占用的存储和处理空间巨大。针对这一问题本文提出了新的滑动窗口式三维watershed... 视频序列分割是实现视频对象提取、处理和识别的基础,也是基于内容的视频压缩和检索的前提。目前普遍采用的watershed算法是全局涨水算法,用于视频分割时占用的存储和处理空间巨大。针对这一问题本文提出了新的滑动窗口式三维watershed算法(SW3DW),通过时间轴上的局部窗口对视频序列进行观察和分割,而在相邻窗口间采用水源区标号传递和局部流域更新相结合的方法,以较小的存储和处理空间实现了局域和全局处理的一致性。理论分析和实验证明该算法能有效性地实现视频序列的分割,为后续视频对象提取和处理创造了条件。 展开更多
关键词 滑动窗口式三维watershed算法 视频序列分割 水源区标号传递 局部流域更新 视频压缩
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基于Lab Windows/CVI平台的水泵试验台测控系统设计
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作者 刘辉 席德科 《仪表技术》 2007年第4期15-16,19,共3页
针对水泵试验台测控系统的实时性、复杂性等特点,文章从硬件设计和软件开发两方面详细描述了测控系统的实现机理,并采用Lab Windows/CVI平台完成了测控软件的开发。实践证明,所设计测控系统操作方便,控制平稳准确,能有效提高测量效率。
关键词 水泵试验台 数据采集 测控 LAB windowS/CVI
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Annealing temperature dependent catalytic water oxidation activity of iron oxyhydroxide thin films 被引量:4
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作者 P.T.Babar B.S.Pawar +5 位作者 A.C.Lokhande M.G.Gang J.S.Jang M.P.Suryawanshi S.M.Pawar Jin Hyeok Kim 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2017年第4期757-761,共5页
Nanostructured iron oxyhydroxide(Fe OOH) thin films have been synthesized using an electrodeposition method on a nickel foam(NF) substrate and effect of air annealing temperature on the catalytic performance is st... Nanostructured iron oxyhydroxide(Fe OOH) thin films have been synthesized using an electrodeposition method on a nickel foam(NF) substrate and effect of air annealing temperature on the catalytic performance is studied. The as-deposited and annealed thin films were characterized by X-ray diffraction(XRD),X-ray photoelectron spectroscopy(XPS), field emission scanning electron microscopy(FE-SEM) and linear sweep voltammetry(LSV) to determine their structural, morphological, compositional and electrochemical properties, respectively. The as-deposited nanostructured amorphous Fe OOH thin film is converted into a polycrystalline Fe;O;with hematite crystal structure at a high temperature. The Fe OOH thin film acts as an efficient electrocatalyst for the oxygen evolution reaction(OER) in an alkaline 1 M KOH electrolyte. The film annealed at 200 °C shows high catalytic activity with an onset overpotential of 240 m V with a smaller Tafel slope of 48 m V/dec. Additionally, it needs an overpotential of 290 mV to the drive the current density of 10 m A/cm;and shows good stability in the 1 M KOH electrolyte solution. 展开更多
关键词 Iron oxyhydroxide/oxide electrocatalyst Electrodeposition method water splitting Linear sweep voltammetry (LSV) X-ray photoelectron spectroscopy (XPS)
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Three-Dimensional Imaging of Pore-Scale Water Flooding Phenomena in Water-Wet and Oil-Wet Porous Media 被引量:2
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作者 Arief Setiawan Tetsuya Suekane +1 位作者 Yoshihiro Deguchi Koji Kusano 《Journal of Flow Control, Measurement & Visualization》 2014年第2期25-31,共7页
The penetration of water during water flooding has been observed over many years using several methods. A microfocused X-ray computed tomography scanner can be used to directly observe 3D water flooding in a nondestru... The penetration of water during water flooding has been observed over many years using several methods. A microfocused X-ray computed tomography scanner can be used to directly observe 3D water flooding in a nondestructive manner. To eliminate the possibility of false images being produced because of X-ray broadening effects, we developed a visualization method by arranging the brightness distribution of all phases involved. Water flooding experiments were conducted using oil-wet and water-wet porous media. The water phase was injected upward into packed glass beads containing an oil phase, and the process was scanned every minute until steady state was reached. Using this scheme, real-time, the water invasion pattern and oil trapping process in clusters of pores and individual pores can be observed clearly. By eliminating false images, the boundary of each phase could be identified with high precision, even in a single pore. Porelevel phenomena, including snap off (which has never before been captured in a real 3D porous medium), piston-like displacement, and the curvature of the interface, were also observed. Direct measurement of the pore throat radius and the contact angle between the wetting and nonwetting phases gave an approximation of the capillary pressure during the piston-like displacement and snap-off processes. 展开更多
关键词 Visualization Porous Medium Pore-Scale water FLOODING OIL Trapping X-Ray CT Scanner
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Computer-Aided Diagnosis for Tuberculosis Classification with Water Strider Optimization Algorithm 被引量:1
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作者 José Escorcia-Gutierrez Roosvel Soto-Diaz +4 位作者 Natasha Madera Carlos Soto Francisco Burgos-Florez Alexander Rodríguez Romany F.Mansour 《Computer Systems Science & Engineering》 SCIE EI 2023年第8期1337-1353,共17页
Computer-aided diagnosis(CAD)models exploit artificial intelligence(AI)for chest X-ray(CXR)examination to identify the presence of tuberculosis(TB)and can improve the feasibility and performance of CXR for TB screenin... Computer-aided diagnosis(CAD)models exploit artificial intelligence(AI)for chest X-ray(CXR)examination to identify the presence of tuberculosis(TB)and can improve the feasibility and performance of CXR for TB screening and triage.At the same time,CXR interpretation is a time-consuming and subjective process.Furthermore,high resemblance among the radiological patterns of TB and other lung diseases can result in misdiagnosis.Therefore,computer-aided diagnosis(CAD)models using machine learning(ML)and deep learning(DL)can be designed for screening TB accurately.With this motivation,this article develops a Water Strider Optimization with Deep Transfer Learning Enabled Tuberculosis Classification(WSODTL-TBC)model on Chest X-rays(CXR).The presented WSODTL-TBC model aims to detect and classify TB on CXR images.Primarily,the WSODTL-TBC model undergoes image filtering techniques to discard the noise content and U-Net-based image segmentation.Besides,a pre-trained residual network with a two-dimensional convolutional neural network(2D-CNN)model is applied to extract feature vectors.In addition,the WSO algorithm with long short-term memory(LSTM)model was employed for identifying and classifying TB,where the WSO algorithm is applied as a hyperparameter optimizer of the LSTM methodology,showing the novelty of the work.The performance validation of the presented WSODTL-TBC model is carried out on the benchmark dataset,and the outcomes were investigated in many aspects.The experimental development pointed out the betterment of the WSODTL-TBC model over existing algorithms. 展开更多
关键词 Computer-aided diagnosis water strider optimization deep learning chest x-rays transfer learning
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NUMERICAL AND EXPERIMENTAL STUDY OF LURE MOVING IN WATER 被引量:1
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作者 Wataru Sekiguchi Naoya Takahashi +1 位作者 Shigeho Noda Ryutaro Himeno 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2013年第3期257-259,共3页
The motion of a lure in water is investigated experimentally and numerically.The lure motion in water of apassing water tank is observed,and the periodic motion is found.From the Fourier analysis,it is found that the ... The motion of a lure in water is investigated experimentally and numerically.The lure motion in water of apassing water tank is observed,and the periodic motion is found.From the Fourier analysis,it is found that the frequency with the largest amplitude in the lateral direction depends on the lip width of the lure.To understand the lure dynamics,a numerical simulation of the flow field around the lure is performed.The shape is measured using an X-ray computer tomography and converted into a voxel model.From visualization,it is found that vortex sheds from its lip correspond to the vibration frequency of the lure. 展开更多
关键词 fishing lure passing water channel voxel model X-ray computer tomography computational fluid dynamics(CFD)
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Evaluation of Total Precipitable Water over East Asia from FY-3A/VIRR Infrared Radiances 被引量:1
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作者 ZHENG Jing SHI Chun-Xiang +1 位作者 LU Qi-Feng XIE Zheng-Hui 《Atmospheric and Oceanic Science Letters》 2010年第2期93-99,共7页
Satellite retrieval of atmospheric water vapor is intended to further understand the role played by the energy and water cycle to determine the Earth's weather and climate.The algorithm for operational retrieval o... Satellite retrieval of atmospheric water vapor is intended to further understand the role played by the energy and water cycle to determine the Earth's weather and climate.The algorithm for operational retrieval of total precipitable water (TPW) from the visible and infrared radiometer (VIRR) onboard Fengyun 3A (FY-3A) employs a split window technique for clear sky radiances over land and oceans during both day and night.The retrieved TPW is compared with that from the moderate resolution imaging spectroradiometer (MODIS) onboard the Terra satellite and data from radiosonde observations (RAOB).During the study period,comparisons show that the FY-3A TPW is in general agreement with the gradients and distributions from the Terra TPW.Their zonal mean difference over East Asia is smaller in the daytime than at night,and the main difference occurs in the complex terrain at mid latitude near 30°N.Compared with RAOB,the zonal FY-3A and the Terra TPW have a moist bias at low latitudes and a dry bias at mid and high latitudes;in addition,the FY-3A TPW performs slightly better in zonal mean biases and the diurnal cycle.The temporal variation of the FY-3A and the Terra TPW generally fits the RAOB TPW with the FY-3A more accurate at night while Terra TPW more accurate during the daytime.Comparisons of correlations,root mean square differences and standard deviations indicate that the FY-3A TPW series is more consistent with the RAOB TPW at selected stations.As a result,the FY-3A TPW has some advantages over East Asia in both spatial and temporal dimensions. 展开更多
关键词 nFY-3A/VIRR total precipitable water split window technique evaluatio.
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Suitability of Some Selected Clay Deposit from Edo, Ogun, Ondo and Ekiti State of Nigeria for Ceramic Water Filters Production 被引量:1
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作者 Smart Adeleye Olubayode Olufiropo Samson Awokola +1 位作者 Enoch Olugbenga Dare Olubayo Timothy Olateju 《Journal of Minerals and Materials Characterization and Engineering》 2016年第1期26-32,共7页
This study is designed to investigate the suitability of selected Nigeria clay deposit for clay based ceramic water filters (CWFs). Clay samples were taken from five randomly selected locations in Nigeria Namely: Okpe... This study is designed to investigate the suitability of selected Nigeria clay deposit for clay based ceramic water filters (CWFs). Clay samples were taken from five randomly selected locations in Nigeria Namely: Okpella (Edo<sup>1</sup>) and Ojirami (Edo<sup>2</sup>) in Edo;Ikere in Ekiti state;FUTA in Ondo state and Onibode in Ogun to determine their suitability for clay based ceramic water filters (CWFs). Experimental analysis for linear shrinkage, water absorption, bulk density, compressive strength X-ray diffraction (XRD) and X-ray Fluorescence (XRF) was carried out on each of the clay samples. Test results reveal that all the clays contain high contents of alumina (Al<sub>2</sub>O<sub>3</sub>) and silica (SiO<sub>2</sub>) with minor contents of P<sub>2</sub>O<sub>5</sub>, Fe<sub>2</sub>O<sub>3</sub>, MgO, K<sub>2</sub>O, MnO and TiO<sub>2</sub>. The average crystal sizes of the clay were between 15 and 27 nm. Lattice structure indicates that the sample is Monoclinic and Anorthic. Ceramic water filters (CWFs) were made from a mixture of clay and sawdust at different volume ratios, and processed into test samples. Water absorption, linear shrinkage and compressive strength of the clay based ceramic filters (CWFs), reveal that as the volume ratio of sawdust increases these properties decrease. Flow rate analysis indicates that Edo and Ekiti ceramic water filters (CWFs) have higher flow rates. The research indicates that Edo and Ekiti Clay with specification of some industrial clays shows that the samples can be recommended for use in clay based ceramic water filters production. 展开更多
关键词 Ceramic water Filters X-Ray Diffraction (XRD) X-Ray Fluorescence (XRF) CLAY
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Scanning electron microscopy coupled with energydispersive X-ray spectrometry for quick detection of sulfuroxidizing bacteria in environmental water samples 被引量:1
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作者 SUN Chengjun JIANG Fenghua +5 位作者 GAO Wei LI Xiaoyun YU Yanzhen YIN Xiaofei WANG Yong DING Haibing 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2017年第1期185-191,共7页
Detection of sulfur-oxidizing bacteria has largely been dependent on targeted gene sequencing technology or traditional cell cultivation, which usually takes from days to months to carry out. This clearly does not mee... Detection of sulfur-oxidizing bacteria has largely been dependent on targeted gene sequencing technology or traditional cell cultivation, which usually takes from days to months to carry out. This clearly does not meet the requirements of analysis for time-sensitive samples and/or complicated environmental samples. Since energy-dispersive X-ray spectrometry(EDS) can be used to simultaneously detect multiple elements in a sample, including sulfur, with minimal sample treatment, this technology was applied to detect sulfur-oxidizing bacteria using their high sulfur content within the cell. This article describes the application of scanning electron microscopy imaging coupled with EDS mapping for quick detection of sulfur oxidizers in contaminated environmental water samples, with minimal sample handling. Scanning electron microscopy imaging revealed the existence of dense granules within the bacterial cells, while EDS identified large amounts of sulfur within them. EDS mapping localized the sulfur to these granules. Subsequent 16S rRNA gene sequencing showed that the bacteria detected in our samples belonged to the genus Chromatium, which are sulfur oxidizers. Thus, EDS mapping made it possible to identify sulfur oxidizers in environmental samples based on localized sulfur within their cells, within a short time(within 24 h of sampling). This technique has wide ranging applications for detection of sulfur bacteria in environmental water samples. 展开更多
关键词 sulfur bacteria energy-dispersive X-ray spectrometry scanning electron microscopy bacteria detection environmental water samples 16S rRNA sequencing
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Multivariate MOF for optimizing atmospheric water harvesting
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作者 Ao Ma Hengjiang Cong Hexiang Deng 《Green Energy & Environment》 SCIE EI CSCD 2022年第4期575-577,共3页
Atmospheric water harvesting offers a powerful and promising solution to address the problem of global freshwater scarcity.In the past decade,significant progress has been achieved in utilizing hydrolytically stable m... Atmospheric water harvesting offers a powerful and promising solution to address the problem of global freshwater scarcity.In the past decade,significant progress has been achieved in utilizing hydrolytically stable metal-organic frameworks as recyclable water-sorbent materials under low relative humidity,especially in those arid areas.Recently,Yaghi's group has employed a combined crystallographic and theoretical technique to decipher the water filling mechanism in MOF-303,where the polar organic linkers rather than the inorganic units of MOF are demonstrated as the key factor.Hence,the hydrophilic strength of the water-binding pocket in MOFs can be optimized through the approach of multivariate modulations,resulting in enhanced water harvesting properties. 展开更多
关键词 Atmospheric water harvesting Metal-organic framework Multivariate strategy Single-crystal X-ray diffraction water-sorption dynamics
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The Design and Test of a Be Window for the ITER Radial X-Ray Camera
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作者 陈肇玺 胡立群 +3 位作者 程勇 雷明准 陈晔斌 宋云涛 《Plasma Science and Technology》 SCIE EI CAS CSCD 2013年第11期1160-1164,共5页
Beryllium (Be) window is a key component of the ITER radial X-ray camera (RXC). The Be window presented in this paper has a mechanical clamping structure, the thickness of the Be foil is 80 μm, and the X-ray thre... Beryllium (Be) window is a key component of the ITER radial X-ray camera (RXC). The Be window presented in this paper has a mechanical clamping structure, the thickness of the Be foil is 80 μm, and the X-ray threshold of the 80 μm Be foil is 1.24 keV. A honeycomb support is designed and applied to strengthen the Be foil to prevent it from breakage when it is exposed to 1 atm perssure. Based on analysis results, the hole diameter of the support is chosen as 4 mm. A metal seal is used to isolate the vacuum on two sides of the Be window, the hollow metal sealing ring ensures the He leakage rate of the Be window being lower than 6× 10^-1 Pa.m^3.s^-1. Baking (240 ℃, 2 h) and vibration(3.3 Hz, 2 h) tests are carried out and the feasibility of the Be window's sealant in these situations is tested. The Be window has good stability that can save maintenance cost as well as enhancing the safety of the RXC. 展开更多
关键词 ITER RXC Be window X-ray threshold honeycomb support met al seal
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Effect of TiO2 Crystallite Diameter on Photocatalytic Water Splitting Rate
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作者 Haruna Banno Ben Kariya +8 位作者 Norifumi Isu Muneaki Ogawa Saeko Miwa Keisuke Sawada Junki Tsuge Shoichiro Imaizumi Hidenori Kato Kyota Tokutake Seiichi Deguchi 《Green and Sustainable Chemistry》 2014年第2期87-94,共8页
The effect of (Pt-loaded)TiO2 crystallite diameter (i.e. Scherrer size) on the photocatalytic water splitting rate was investigated. (Pt-loaded)TiO2 powders with a wide range of crystallite diameters from about 16 to ... The effect of (Pt-loaded)TiO2 crystallite diameter (i.e. Scherrer size) on the photocatalytic water splitting rate was investigated. (Pt-loaded)TiO2 powders with a wide range of crystallite diameters from about 16 to 45 nm with a blank region between about 23 and 41 nm were prepared by various annealing processes from an identical TiO2 powder. Water splitting experiments with these powders were carried out with methanol as an oxidizing sacrificial agent. It was found that the photocatalytic water splitting rate was sensitively affected by the crystallite diameter of the (Pt-loaded)TiO2 powder. More concretely, similar steep improvements of photocatalytic water splitting rates from around 15 and a little over 2 to about 30 μmol·m-2hr-1?were obtained in the two (Pt-loaded)TiO2 crystallite diameters ranging from 16 to 23 and from 41 to 45 nm, respectively. 展开更多
关键词 Photocatalytic water SPLITTING TIO2 CRYSTALLITE DIAMETER Scherrer Size X-Ray Diffraction Critical water ANNEAL
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Evaluation of Preservation Effect by Aquo-Siloxane Method towards Water Permeation and Material Diffusion into Porous Rocks
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作者 Akira Sato Minami Egashira Michiyo Obata 《Materials Sciences and Applications》 2017年第6期419-435,共17页
Various kinds of heritages, such as architectures, statues, grave posts and towers, are made by stone, and they are facing the crisis of weathering. Therefore, it is necessary to give appropriate treatments to keep th... Various kinds of heritages, such as architectures, statues, grave posts and towers, are made by stone, and they are facing the crisis of weathering. Therefore, it is necessary to give appropriate treatments to keep them in good conditions. Kyushu Research Institute for Cultural Properties Inc. and Kumamoto University introduced a new method, Aquo-Siloxane Method, in order to protect the stone heritages. In this study, preservation effect by Aquo-Siloxane method towards water permeation and material diffusion was verified. Here one-dimensional permeation and diffusion tests were conducted, and the intrinsic permeability and diffusion coefficient of rock samples with and without Aquo-Siloxane treatments were evaluated. As rock samples, 3 types of sandstones and concrete were applied. It was found that the permeability decreased to less than 1/10 to 1/100 of without Aquo-Siloxane treatment, and that the effect gradually developed during more than one year. One-dimensional diffusion tests were also conducted, and the diffusion process in rock samples are visualized by X-ray CT scanner system. It was confirmed internal structures of samples are clearly visualized, and that the diffusion process was also visualized as X-ray CT images. In order to extract the necessary information due to diffusion, image subtraction method was applied to image data. Then, by comparing obtained CT image data and numerical solutions, diffusion coefficients of rock samples with and without Aquo-Siloxane treatments were evaluated. As a result, diffusion coefficients also became smaller by applying Aquo-Siloxane treatments. It is revealed that material movement due to diffusion was also efficiently suppressed by applying Aquo-Siloxane method. Finally, Aquo-Siloxane method was applied to a stone heritage. It was found that no more chippings and cracks were observed and that the heritage has been kept in good condition for at least four years. 展开更多
关键词 Aquo-Siloxane METHOD STONE Heritages water PERMEATION DIFFUSION X-RAY CT
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Water Quality Monitoring of the Bezerra River (Cascavel, Brazil) Using SR-TXRF Technique
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作者 Phallcha Luízar Obregón Fernando Rodolfo Espinoza-Quinones Aparecido Nivaldo Módenes 《Journal of Chemistry and Chemical Engineering》 2014年第6期587-595,共9页
The present study aims to monitor and assess the water quality of the Bezerra River located in the Western Brazilian Parana state. For the monitoring of river waters, six samplings were established per month during on... The present study aims to monitor and assess the water quality of the Bezerra River located in the Western Brazilian Parana state. For the monitoring of river waters, six samplings were established per month during one year. As indicators of the water quality, physico-chemical parameters such as water temperature, pH, turbidity, dissolved oxygen and COD (chemical oxygen demand) were chosen, as well as trace and majority element concentrations. It is noteworthy that the mean annual values of conductivity, turbidity and COD have progressively increased along the river with maximum values after the Cascavel western sewage treatment plant. Only 13 elements were found in the six collection points, but the metallic elements Cr, Mn, Fe, Cu and Zn have shown concentrations above the maximum limits recommended by Brazilian environmental legislation, suggesting the presence of highly polluting anthropogenic sources. Correlation analyses were used to determine the spatio-variability of water quality variables. The six collection sites were grouped into two clusters, with the element composition in the first cluster (sites 1, 2 and 6) being due to strong anthropogenic activities. The study of the Bezerra River water quality could help to develop municipal environmental policies and help with the management of water conservation in the Bezerra River basin. 展开更多
关键词 River water pollution physico-chemical parameters SR-TXRF (synchrotron radiation total reflection X-ray fluorescence) technique element concentrations statistical analysis.
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New Insight into Electronic Neutrino Creation under X-Ray Absorption by Water Tetrahedron Intercalated with Hydronium Ion (H3O^+)
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作者 Alexander V. Udal'tsov 《Journal of Energy and Power Engineering》 2017年第11期693-705,共13页
In contrast to so-called Auger process resulting in electron ejection from oxygen atom of water molecule under X-ray absorption, the coupling of the opposite charges in liquid water leads to polaronic exciton formatio... In contrast to so-called Auger process resulting in electron ejection from oxygen atom of water molecule under X-ray absorption, the coupling of the opposite charges in liquid water leads to polaronic exciton formation. As a result, polaronic exciton stabilized by the structure of water tetrahedron can serve as the reaction center for deuterium creation under X-ray absorption. In this case, X-ray emission spectra of H:O and D20 give a clue for the deciphering of the events followed by X-ray photon absorption. It appears to be that spin-orbit interaction under proton sharing and the interaction between LO (longitudinal optical) phonon and bipolaron in the excited state are responsible for the energy levels determining neutrino energy. The energy gap between the levels with pATe andplle spin configurations of proton and electron is found to be 325.51 cm^-1 in the case of the spin-orbit interaction in polaronic exciton, while 1,556.054 cm^-1 under LO phonon interaction with the proton of the bipolaron producing the change of the nucleus spin direction to the opposite. 展开更多
关键词 water X-ray emission polaronic exciton Compton wavelength neutrino.
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伊犁河三角洲水资源条件变化对景观格局演变的影响 被引量:1
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作者 陈启慧 纪璐 +6 位作者 李琼芳 白浩男 韩幸烨 姚佳 崔罡 周正模 杨坤凡 《水资源保护》 EI CAS CSCD 北大核心 2024年第2期90-99,共10页
在分析1992—2020年伊犁河三角洲水资源条件和定量评估研究期内土地利用变化的基础上,选取景观类型水平和景观水平指数解析景观格局变化特征,采用皮尔逊相关系数分析了水资源条件变化对景观格局指数的影响。结果表明:乌斯热尔玛水文站... 在分析1992—2020年伊犁河三角洲水资源条件和定量评估研究期内土地利用变化的基础上,选取景观类型水平和景观水平指数解析景观格局变化特征,采用皮尔逊相关系数分析了水资源条件变化对景观格局指数的影响。结果表明:乌斯热尔玛水文站年径流总体偏大,巴尔喀什湖年平均水位在2002年发生突变,三角洲水资源补给总体处于增加状态;湿地和稀疏植被面积增大且聚集性增强,裸地向稀疏植被转化且优势度不断下降,林地破碎程度剧烈;景观水平指数在时程上呈阶段性变化,2016年伊犁河三角洲破碎化程度最低,在空间上伊犁河沿岸连通性增强,巴尔喀什湖沿岸景观多样性增加;景观水平指数与巴尔喀什湖年平均水位相关性最高,与乌斯热尔玛水文站年径流量的相关性次之,与伊犁河三角洲年降水量的相关性最低,且景观水平指数对三角洲水资源条件变化存在迟滞响应。 展开更多
关键词 景观格局 水资源 移动窗口法 土地利用 伊犁河三角洲
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基于水资源空间均衡的“四水四定”调控模型构建 被引量:3
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作者 魏豪杉 王红瑞 +3 位作者 郏鹏鑫 周利超 李永坤 刘昌明 《水资源保护》 EI CAS CSCD 北大核心 2024年第3期71-77,共7页
为实现未来不同时间尺度下的水资源空间均衡与动态调控,创建了一套完整严谨、可动态调控的“四水四定”模型体系。通过模糊信息粒化窗口的支持向量机模型预测区域未来总用水量,利用基于时间序列相似性分析的自回归支持向量机模型预测区... 为实现未来不同时间尺度下的水资源空间均衡与动态调控,创建了一套完整严谨、可动态调控的“四水四定”模型体系。通过模糊信息粒化窗口的支持向量机模型预测区域未来总用水量,利用基于时间序列相似性分析的自回归支持向量机模型预测区域未来分用水量,并对两类数据进行不确定性分析;构建了复杂回归函数对各类用水指标进行情景预测,经统计检验后将其作为当前用水模式下未来用水指标;构建了“四水四定”水资源承载力模型和水资源空间均衡模型,基于未来总用水量、未来各分用水量、未来用水指标,选用水资源负载系数、用水效益和水土资源匹配系数3个指标,结合基尼系数量化水资源空间均衡度,分析当前用水模式下未来水资源均衡度;构建了最优化模型,以最小化基尼系数为目标函数调整未来用水模式,实现水资源动态调控。所创建的模型体系可以实现未来不同时间尺度下的水资源空间均衡与动态调控。 展开更多
关键词 “四水四定” 水资源空间均衡 水资源动态调控 时间序列相似性 支持向量机模型 模糊信息粒化窗口
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基于动态窗口法的近海水域船舶避障算法研究 被引量:1
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作者 李光泽 俞万能 +1 位作者 廖卫强 吴川博 《中国舰船研究》 CSCD 北大核心 2024年第1期230-237,共8页
[目的]提出一种改进的动态窗口法,以解决近海水域智能船舶在面对夹击及动静混合会遇时无法有效避让的船舶避障问题。[方法]为得到在近海水域航行的船舶约束条件,针对近海水域对船舶避障的影响因素进行分析,同时提出近海水域船舶航行最... [目的]提出一种改进的动态窗口法,以解决近海水域智能船舶在面对夹击及动静混合会遇时无法有效避让的船舶避障问题。[方法]为得到在近海水域航行的船舶约束条件,针对近海水域对船舶避障的影响因素进行分析,同时提出近海水域船舶航行最低避障要求;然后对动态窗口法(DWA)的目标函数进行优化改进,并将其与船舶和障碍物的距离相关联,以提升船舶在航行图中的安全性,同时将目标函数中的航向权值引入船舶会遇态势判断,以使目标船舶可以有效判断船舶的避障责任;最后,通过仿真模拟验证改进算法的有效性。[结果]仿真结果表明,所提的改进算法在分别遭遇夹击以及复杂会遇的情况下,能够清晰地判断船舶的避障责任,降低航行过程中的速度变化陡峭度,且所规划的船舶航行路径可有效提升船舶航行的安全性。[结论]所提避障算法可为解决近海水域智能船舶遭遇复杂会遇情景的避碰失败问题提供参考。 展开更多
关键词 智能船舶 避障 动态窗口法 自适应权值 近海水域
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