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EFFECT OF TROPICAL CYCLONE PRECIPITATION ON ALLEVIATING THE DROUGHT SITUATION IN THE SOUTHEAST COASTAL REGIONS OF CHINA DURING SUMMER AND AUTUMN:USING THE IMPROVED OBJECTIVE SYNOPTIC ANALYSIS TECHNIQUE 被引量:1
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作者 蒋昱鑫 李嘉鹏 王元 《Journal of Tropical Meteorology》 SCIE 2016年第3期277-286,共10页
To quantitatively study the role of tropical cyclone precipitation(TCP) on alleviating the drought in the southeast coastal region of China(SCR) during summer and autumn,the objective synoptic analysis technique(OSAT)... To quantitatively study the role of tropical cyclone precipitation(TCP) on alleviating the drought in the southeast coastal region of China(SCR) during summer and autumn,the objective synoptic analysis technique(OSAT),improved for consistency and rationality,was used to separate the TCP data on the summers and autumns of 1963-2005 on the basis of daily precipitation data from stations and tropical cyclone best track data.After defining the season drought index,the actual drought distribution and the assumed drought distribution without TCP were acquired.The results showed that within 1 000 km from the southeast coastline of China,TCP accounted for 11.3%of natural precipitation(NP).Without TCP,the drought index in the SCR during summer would have increased from 0.2 to 0.6 or even above 1.0 in some regions whereas the drought index during autumn would have increased from 0.4 to 0.6 or above 1.2 in some regions.The impact of TCP on drought decreases progressively from the southeast coastline to the inland regions.The TCP proportion(TCPP) showed a significant negative correlation with the drought index in many regions of the southeast,and the significant region is wider in autumn than in summer.TCP relieved the drought most significantly within a range of 0-500 km from the southeast coastline.This drought relief showed different characteristics for the interannual variability in summer and autumn,and the cross wavelet transform indicated that the impact of TCP on drought mainly lies in 2-4-year time scales.In particular,there was a significant effect during the summers of 1977-1985 and in the autumns following that of 1985.Therefore,TCP has indeed largely alleviated drought in the SCR during summer and autumn. 展开更多
关键词 TROPICAL CYCLONE precipitation DROUGHT objective SYNOPTIC analysis technique
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Evaluation of Fabric Pilling Using Light Projection and Image Analysis Techniques 被引量:1
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作者 徐增波 陆凯 黄秀宝 《Journal of China Textile University(English Edition)》 EI CAS 2000年第4期80-86,共7页
A new instrument based on light projection and image analysis techniques for assessing fabric pilling is presented. This system can automatically detect the pills from the successive sections of the fabric surface, wh... A new instrument based on light projection and image analysis techniques for assessing fabric pilling is presented. This system can automatically detect the pills from the successive sections of the fabric surface, which can make up for the limitation of both the gray level image -analysis techniques and laser triangulab’on techniques. The test of a large number of worsted wool fabric samples shows that it can objectively characterize the degree of pilling by using fuzzy sets and has good accordance with human visual inspection. 展开更多
关键词 FABRIC PILLING LIGHT PROJECTION Image analysis FUZZY SETS
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Studies on the Catalyst for Oxidation of o-Xylene to Phthalic Anhydride by the Image Texture Analysis Technique
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作者 DUAN Shi-duo and CHE Hui (Department of Chemistry, Tianjin University, Tianjin, 300072)WANG Ji-fen (Department of Computer and Science Engineering, Tianjin University, Tianjin, 300072) 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 1992年第2期104-109,共6页
The present paper covers surface texture features of the catalysts for the oxidation of o-xylene to phthalic anhydride (PA) investigated by the Image Texture Analysis Technique and obviously corresponding relationship... The present paper covers surface texture features of the catalysts for the oxidation of o-xylene to phthalic anhydride (PA) investigated by the Image Texture Analysis Technique and obviously corresponding relationships between the catalyst activity and its texture features (entropy(F9) and angular second moment(F1)).By means of the two texture features(F9 and F1), the effects of promoters K2O and Al2O3 on the properties of the catalysts were analysed, a higher active catalyst’ s surface texture model for active catalysts is given:d(F) = 0. 00693×F9 - 0. 98039×F1 - 0.03078 】 0The results show that the Image Texture Analysis Technique would be a useful tool for the studies of catalyst surface structure and computer-aided design of catalysts. 展开更多
关键词 TEXTURE analysis Catalyst’ s ACTIVITY Surface FEATURE
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Absolute Neutron Activation Analysis Technique of a Large Crude Oil Sample
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作者 V. G. Zinovyev V. V. Martynov +4 位作者 Yu. E. Loginov E. M. Korotkih G. I. Shulyak T. M. Tukavina P. A. Sushkov 《World Journal of Nuclear Science and Technology》 2013年第4期136-142,共7页
This manuscript presents an application of calculation methods in neutron activation analysis (NAA) of a large crude oil sample. Monte-Carlo computer code was developed. The computer code calculates neutron cross sect... This manuscript presents an application of calculation methods in neutron activation analysis (NAA) of a large crude oil sample. Monte-Carlo computer code was developed. The computer code calculates neutron cross sections and neutron flux density distribution in the interior large sample. ENDF/B-VII.0 data files and ENSDF BNL-NCS-51655-01/02-Rev data files were used as nuclear databases in our computer code. HPGe planar detector efficiency registration technique and the software were developed for the absolute NAA technique of the large sample. The concentrations of Na, K, Ca, Sc, Cr, Fe, Co, Ni, Cu, Zn, Ga, As, Br, Sr, Zr, Mo, Ag, Sb, Cs, Ba, Ce, Nd, Sm, Eu, Tb, Dy, Ho, Tm, Yb, Lu, Hf, Ta, W, Pt, Au, Hg, Th and U in the crude oil samples of Eastern Siberia oilfield were determined using calculation and relative techniques in the concentration range from 10-9 to 0.5%. 展开更多
关键词 NEUTRON FLUX NEUTRON ACTIVATION analysis ENDF Datab
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Optimization of Baosteel's digital automatic analysis technique for maceral specification
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作者 SUN Weizhou HU Desheng ZOU Danping 《Baosteel Technical Research》 CAS 2013年第2期26-29,共4页
Baosteel developed a digital automatic analysis technique for maceral specification in 2002.This analysis system combines digital image processing,graphics,databases,expert systems,artificial intelligence and other ad... Baosteel developed a digital automatic analysis technique for maceral specification in 2002.This analysis system combines digital image processing,graphics,databases,expert systems,artificial intelligence and other advanced technologies.After 6 years of application in coke production,the system proved itself successful in coal quality testing and coal blending guidance on maceral.However,during this long process,some inadequacies were found that impacted the precision and accuracy of the analysis.So,in 2008 Baosteel began to work on improving the coal maceral analysis system. The improvements included the following:further upgrading and enhancing the analysis performance of microscopic images;extending the gray levels to increase the reflectance measurement accuracy 64 times;changing the focus method and effectively eliminating the interference of halo.In addition,an improved image recognition method was adopted to make the extraction of vitrinite more accurate and a new model of coal constituent algorithm was added which can accurately determine the composition of maceral(exinite,vitrinite,inertinite).Since these improvements were completed, the system has achieved higher automation,speed and accuracy,collected more information and performed more accurate maceral analysis for coke production.Meanwhile,the improved system has provided a reliable analytical basis for the further study on the relationship between coke quality and coal blending. 展开更多
关键词 自动分析技术 显微组分 宝钢 规格 数字图像处理 专家系统 优化 焦炭生产
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Determination of the Bromine, Manganese and Antimony in Nicotiana tabacum Solanaceae by Using the Neutron Activation Analysis Technique
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作者 Tufic Madi Filho Elson Barros Ferreira +1 位作者 José Roberto Berretta Maria da Conceição Costa Pereira 《Materials Sciences and Applications》 2022年第2期91-106,共16页
Tobacco addiction has been mentioned as a leading cause of preventable illnesses and premature disability. Smoking is the main cause of lung cancer and one of the factors that most contribute to the occurrence of hear... Tobacco addiction has been mentioned as a leading cause of preventable illnesses and premature disability. Smoking is the main cause of lung cancer and one of the factors that most contribute to the occurrence of heart diseases, among others. The herbaceous species Nicotiana tabacum is a plant of the solanaceae family used for tobacco production. Some authors have conducted research about heavy metals and the toxicity of tobacco. It is, frequently, found in low concentrations in the ground, and superficial and underground waters, even though they do not have environmental anthropogenic contributions. However, with the increase of industrial activities and mining together with the agrochemical use of contaminated organic and inorganic fertilizers, an alteration of the geochemical cycle occurs. As a consequence, the natural flow of these materials increases and is released into the biosphere, where they are often accumulated in the superior layer of the ground, accessible to the roots of the plants. During planting and plant development, fertilizers and insecticides, including organochlorines and organophosphates, are used;consequently, the smoke from cigarette smoking presents various toxic substances, such as bromine (Br), manganese (Mn) and antimony (Sb), elements studied in this work. The procedures for the preparation of the samples were carried out in our laboratories and submitted to irradiation with thermal neutrons at Nuclear and Energy Research Institute (IPEN/CNEN-SP), in the Atomic Energy Institute IEA-R1 research reactor. The irradiated material was, then, analyzed by gamma spectrometry, using a high purity germanium detector (HPGe). 展开更多
关键词 Nicotiana tabacum BROMINE MANGANESE ANTIMONY Neutron Activation analysis
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Risk Analysis Technique on Inconsistent Interview Big Data Based on Rough Set Approach
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作者 Riasat Azim Abm Munibur Rahman +1 位作者 Shawon Barua Israt Jahan 《Journal of Data Analysis and Information Processing》 2016年第3期101-114,共14页
Rough set theory is relativly new to area of soft computing to handle the uncertain big data efficiently. It also provides a powerful way to calculate the importance degree of vague and uncertain big data to help in d... Rough set theory is relativly new to area of soft computing to handle the uncertain big data efficiently. It also provides a powerful way to calculate the importance degree of vague and uncertain big data to help in decision making. Risk assessment is very important for safe and reliable investment. Risk management involves assessing the risk sources and designing strategies and procedures to mitigate those risks to an acceptable level. In this paper, we emphasize on classification of different types of risk factors and find a simple and effective way to calculate the risk exposure.. The study uses rough set method to classify and judge the safety attributes related to investment policy. The method which based on intelligent knowledge accusation provides an innovative way for risk analysis. From this approach, we are able to calculate the significance of each factor and relative risk exposure based on the original data without assigning the weight subjectively. 展开更多
关键词 Rough Set Theory Big Data Risk analysis Data Mining Variable Weight Significance of Attribute Core Attribute Attribute Reduction
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Application of experimental modal analysis technique to structural design of linear vibrating screen 被引量:1
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作者 李文英 米朝阳 +1 位作者 武望国 熊诗波 《Journal of Coal Science & Engineering(China)》 2004年第1期88-90,共3页
A large model of the screen was mounted in the laboratory for studying its modal performance. The model is suspended with steel ropes. Modal test was carried out with artificially exciting by 500 g impacting hammer an... A large model of the screen was mounted in the laboratory for studying its modal performance. The model is suspended with steel ropes. Modal test was carried out with artificially exciting by 500 g impacting hammer and 100 kg exciting force shaker respectively. Synthesis and correction of the modal parameters are obtained from both testing methods. Design faults of vibrating screen were determined based on the analy-sis and dynamic correction of structure approaches about the screen was put forward finally. 展开更多
关键词 振动筛 线性振动 实验模态分析技术 结构设计 动力学设计
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Gold Resources Potential Assessment in Eastern Kunlun Mountains of China Combining Weights-of-evidence Model with GIS Spatial Analysis Technique 被引量:4
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作者 HE Binbin CHEN Cuihua LIU Yue 《Chinese Geographical Science》 SCIE CSCD 2010年第5期461-470,共10页
Resources potential assessment is one of the fields in geosciences,which is able to take great advantage of GIS technology as a substitution of traditional working methods.The gold resources potential in the eastern K... Resources potential assessment is one of the fields in geosciences,which is able to take great advantage of GIS technology as a substitution of traditional working methods.The gold resources potential in the eastern Kunlun Mountains,Qinghai Province,China was assessed by combining weights-of-evidence model with GIS spatial analysis technique.All the data sets used in this paper were derived from an established multi-source geological spatial database,which contains geological,geophysical,geochemical and remote sensing data.Three multi-class variables,i.e.,structural intersection,Indosinian k-feldspar granite and regional fault,were used in proximity analysis to examine their spatial association with known gold deposits.A prospectivity map was produced by weights-of-evidence model based on seven binary evidential maps,all of which had passed a conditional independence test.The study area was divided into three target zones of high potential,moderate potential and low potential areas,among which high potential areas and moderate potential areas accounted for 20% of the total area and contained 32 of the 43 gold deposits.The results show that the gold resources potential assessment in the eastern Kunlun Mountains has a higher precision. 展开更多
关键词 资源潜力评价 空间分析技术 GIS技术 东昆仑山 黄金资源 中国结 证据 权值
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Using Link Analysis Technique with a Modified Shortest-Path Algorithm to Fight Money Laundering
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作者 CHEN Yunkai MAI Quanwe LU Zhengding 《Wuhan University Journal of Natural Sciences》 CAS 2006年第5期1352-1356,共5页
Effective link analysis techniques are needed to help law enforcement and intelligence agencies fight money laundering. This paper presents a link analysis technique that uses a modified shortest-path algorithms to id... Effective link analysis techniques are needed to help law enforcement and intelligence agencies fight money laundering. This paper presents a link analysis technique that uses a modified shortest-path algorithms to identify the strongest association paths between entities in a money laundering network. Based on two-tree Dijkstra and Priority-First-Search (PFS) algorithm, a modified algorithm is presented. To apply the algorithm, a network representation transformation is made first. 展开更多
关键词 联结分析 短路算法 法律实施 智能处理
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Progress of neutron induced prompt gamma analysis technique in 1988~2003 被引量:3
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作者 JINGShi-Wei LIUYu-Ren CHIYan-Tao TIANYu-Bing CAOXi-Zheng ZHAOXin-Hui RENWan-Bin LIULin-Mao 《Nuclear Science and Techniques》 SCIE CAS CSCD 2004年第2期119-122,共4页
This paper described new development of the neutron induced prompt gamma-ray analysis(NIPGA) technology in 1988-2003.The pulse fast-thermal neutron activation analysis method,which utilized the inelastic reaction and ... This paper described new development of the neutron induced prompt gamma-ray analysis(NIPGA) technology in 1988-2003.The pulse fast-thermal neutron activation analysis method,which utilized the inelastic reaction and capture reaction jointly,was employed to measure the elemental contents more efficiently.Lifetime of the neutron generator was more than 10000h and the performance of detector and MCA reached a high level.At the same time,Monte Carlo library least-square method was used to solve the nonlinearity problem in the NIPGA. 展开更多
关键词 中子诱导瞬发γ射线分析 NIPGA 俘获反应 非弹性反应 MonteCarlo仿真
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Multi-Elemental Analysis and 2D Image Mapping within Roots, Leaves and Seeds from O. glaberrima Rice Plants Using Micro-PIXE Technique
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作者 Alassane Traore Anna Ndiaye +6 位作者 Christopher Bongani Mtshali Manneh Baboucarr Jean Paul Latyr Faye Daouda Mbodj Kandiaba Traore Tapha Gueye Ababacar Sadikhe Ndao 《World Journal of Nuclear Science and Technology》 CAS 2024年第2期97-106,共10页
Understanding metal accumulation at organ level in roots, leaves and seeds in O. glaberrima (OG) is crucial for improving physiological and metabolic aspects in growing Asian and African rice in salted areas. The micr... Understanding metal accumulation at organ level in roots, leaves and seeds in O. glaberrima (OG) is crucial for improving physiological and metabolic aspects in growing Asian and African rice in salted areas. The micro-analytical imaging techniques are required to reveal its accumulation and distribution within plant tissues. PIXE studies have been performed to determine different elements in rice plants. The existing microbeam analytical technique at the iThemba LABS will be applied for the 2D image mapping of fresh rice tissues to perform a concentration of low atomic mass elements (such as Al, Si, P, S, Cl, Ca, Ti, Mn, Fe, Cu, Br, Zn and K) with detection limits of typically 1-10 μg/g. Comparison of the distribution of the elements between leaves, root and seed samples using uptake and distribution of elements in particular environmental conditions with potential amount of salt in water have been performed. We are also expecting to indicate metal exclusion as salt tolerance strategies from leaves, root, and seed compartments using matrix correlation between samples and between elements on rice species. 展开更多
关键词 PIXE 2D Mapping Rice Concentration Elemental analysis
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Analysis of a New Toothbrushing Technique through Plaque Removal Success
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作者 Elhadi A. A. Shkorfu Serkan Kurt +2 位作者 Fatih Atalar Ali Olamat Aysel Ersoy 《Open Journal of Stomatology》 2024年第3期133-152,共20页
Background/Aims: Determining the levels of oral health and the quality of dental care are fundamental to building concepts of oral health. This study aims to assess toothbrushing techniques using a technical and physi... Background/Aims: Determining the levels of oral health and the quality of dental care are fundamental to building concepts of oral health. This study aims to assess toothbrushing techniques using a technical and physical model, clarifying how children and pre-adults learn to brush their teeth. Materials and Methods: Data were recorded from 23 participants, both male and female of various ages, using a proposed electronic toothbrush equipped with X-Y-Z axes pathways. The data, collected before and after training experiments, were processed with MATLAB to generate plots for the three axes. Results: The study revealed that most parameter values, such as Mean Difference Between Amplitudes (MAV, 6.00), Wilson Amplitude (WAMP, 179.419), and Average Amplitude Coupling (AAC, 1.270), decreased from before to after the experiments. Furthermore, the average overall epoch lengths (AVG) showed a 75% reduction in movement amplitude between the two experiments. Conclusion: Dentist observations indicated which brushing methods were acceptable or not. Analytical values suggest that individuals learn the toothbrushing technique effectively, and medical observations clearly demonstrate the success of the proposed method. 展开更多
关键词 Techno-Physical Toothbrushing Oral Hygiene Education Dental Technology Plaque analysis
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Bubble dynamics properties of B-particles in a quasi-2D gas-solid fluidized bed:Computational particle fluid dynamics numerical simulation and post-processed by digital image analysis technique
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作者 Zemin Yuan Zhong Huang +4 位作者 Guotao Qin Guanjia Zhao Suxia Ma Hairui Yang Guangxi Yue 《Particuology》 SCIE EI CAS CSCD 2024年第3期223-238,共16页
Bubble dynamics properties play a crucial and significant role in the design and optimization of gas-solid fluidized beds.In this study,the bubble dynamics properties of four B-particles were investigated in a quasi-t... Bubble dynamics properties play a crucial and significant role in the design and optimization of gas-solid fluidized beds.In this study,the bubble dynamics properties of four B-particles were investigated in a quasi-two-dimensional(quasi-2D)fluidized bed,including bubble equivalent diameter,bubble size distribution,average bubble density,bubble aspect ratio,bubble hold-up,bed expansion ratio,bubble radial position,and bubble velocity.The studies were performed by computational particle fluid dynamics(CPFD)numerical simulation and post-processed with digital image analysis(DIA)technique,at superficial gas velocities ranging from 2u_(mf) to 7u_(mf).The simulated results shown that the CPFD simulation combining with DIA technique post-processing could be used as a reliable method for simulating bubble dynamics properties in quasi-2D gas-solid fluidized beds.However,it seemed not desirable for the simulation of bubble motion near the air distributor at higher superficial gas velocity from the simulated average bubble density distribution.The superficial gas velocity significantly affected the bubble equivalent diameter and evolution,while it had little influence on bubble size distribution and bubble aspect ratio distribution for the same particles.Both time-averaged bubble hold-up and bed expansion ratio increased with the increase of superficial gas velocity.Two core-annular flow structures could be found in the fluidized bed for all cases.The average bubble rising velocity increased with the increasing bubble equivalent diameter.For bubble lateral movement,the smaller bubbles might be more susceptible,and superficial gas velocity had a little influence on the absolute lateral velocity of bubbles.The simulated results presented a valuable and novel approach for studying bubble dynamics properties.The comprehensive understanding of bubble dynamics behaviors in quasi-2D gas-solid fluidized beds would provide support in the design,operation,and optimization of gas-solid fluidized bed reactors. 展开更多
关键词 Bubble dynamics properties CPFD simulation Quasi-2D gas-solid fluidized bed Digital image analysis
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GIS-Based Multi-Criteria Decision Analysis (MCDA) and Analytical Hierarchy Process (AHP) Techniques to Derive Flood Risks Management on Rice Productivity in Gishari Marshland
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作者 Jean Nepo Nsengiyumva Emmanuel Nshimiyimana +7 位作者 Jean Marie Ntakirutimana Phocas Musabyimana Yvonne Akimana Fred Shema Set Niyitanga Séverin Hishamunda Callixte Musinga Mpamabara Eliezel Habineza 《Journal of Geoscience and Environment Protection》 2024年第3期222-249,共28页
Floods are phenomenon with significant socio-economic implications mainly for human loss, agriculture, livestock, soil loss and land degradation, for which many researchers try to identify the most appropriate methodo... Floods are phenomenon with significant socio-economic implications mainly for human loss, agriculture, livestock, soil loss and land degradation, for which many researchers try to identify the most appropriate methodologies by analyzing their temporal and spatial development. This study therefore attempts to employ the GIS-based multi-criteria decision analysis and analytical hierarchy process techniques to derive the flood risks management on rice productivity in the Gishari Agricultural Marshland in Rwamagana district, Rwanda. Here, six influencing potential factors to flooding, including river slope, soil texture, Land Use Land Cover through Land Sat 8, rainfall, river distance and Digital Elevation Model are considered for the delineation of flood risk zones. Data acquisition like Landsat 8 images, DEM, land use land cover, slope, and soil class in the study area were considered. Results showed that if the DEM is outdated or inaccurate due to changes in the terrain, such as construction, excavation, or erosion, the predicted flood patterns might not reflect the actual water flow. This could result unexpected flood extents and depths, potentially inundating rice fields that were not previously at risk and this, expectedly explained that the increase 1 m in elevation would reduce the rice productivity by 0.17% due to unplanned flood risks in marshland. It was found that the change in rainfall distribution in Gishari agricultural marshland would also decrease the rice productivity by 0.0018%, which is a sign that rainfall is a major factor of flooding in rice scheme. Rainfall distribution plays a crucial role in flooding analysis and can directly impact rice productivity. Oppositely, another causal factor was Land Use Land Cover (LULC), where the Multivariate Logistic Regression Model Analysis findings showed that the increase of one unit in Land Use Land Cover would increase rice productivity by 0.17% of the total rice productivity from the Gishari Agricultural Marshland. Based on findings from these techniques, the Gishari Agricultural Marshlands having steeped land with grassland is classified into five classes of flooding namely very low, low, moderate, high, and very high which include 430%, 361%, 292%, 223%, and 154%. Government of Rwanda and other implementing agencies and major key actors have to contribute on soil and water conservation strategies to reduce the runoff and soil erosion as major contributors of flooding. 展开更多
关键词 Multi Criteria Decision analysis (MCDA) Analytical Hierarchy analysis (AHA) GIS RS and DEM
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Qualitative analysis of aromatic compounds via 1D TOCSY techniques
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作者 Wenbo Dong Qi Zhao +3 位作者 Jiancheng Zhao Jiarong Zhang Yingxiong Wang Yan Qiao 《Magnetic Resonance Letters》 2024年第1期21-27,共7页
The aromatic compounds,including o-xylene,m-xylene,p-xylene,and ethylbenzene,primarily originate from the catalytic reforming of crude oil,and have a wide variety of applications.However,because of similar physical an... The aromatic compounds,including o-xylene,m-xylene,p-xylene,and ethylbenzene,primarily originate from the catalytic reforming of crude oil,and have a wide variety of applications.However,because of similar physical and chemical properties,these compounds are difficult to be identified by gas chromatography(GC)without standard samples.With the development of modern nuclear magnetic resonance(NMR)techniques,NMR has emerged as a powerful and efficient tool for the rapid analysis of complex and crude mixtures without purification.In this study,the parameters of one-dimensional(1D)total correlation spectroscopy(TOCSY)NMR techniques,including 1D selective gradient TOCSY and 1D chemicalshift-selective filtration(CSSF)with TOCSY,were optimized to obtain comprehensive molecular structure information.The results indicate that the overlapped signals in NMR spectra of nonpolar aromatic compounds(including o-xylene,m-xylene,p-xylene and ethylbenzene),polar aromatic compounds(benzyl alcohol,benzaldehyde,benzoic acid),and aromatic compounds with additional conjugated bonds(styrene)can be resolved in 1D TOCSY.More importantly,full molecular structures can be clearly distinguished by setting appropriate mixing time in 1D TOCSY.This approach simplifies the NMR spectra,provides structural information of entire molecules,and can be applied for the analysis of other structural isomers. 展开更多
关键词 1D TOCSY NMR technologies XYLENES Aromatic compounds Structure information of entire molecular Qualitative analysis
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Sustainable development of unconventional resources: Analysis of the transient linear flow oriented straight-line analysis technique
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作者 Dan Xue Liangliang Jiang +7 位作者 Zixiang Wei Maojie Chai Jiang Liu Peng Deng Fuhe Lin Jian Li Jiansheng Zhang Zhangxing Chen 《Energy Reviews》 2024年第1期49-75,共27页
On the backdrop of dwindling conventional reserves,unconventional reservoirs have emerged as a pivotal chapter in resource extraction.Despite their challenges,such as low permeability,complex fluid storage,and flow me... On the backdrop of dwindling conventional reserves,unconventional reservoirs have emerged as a pivotal chapter in resource extraction.Despite their challenges,such as low permeability,complex fluid storage,and flow mechanisms,hydraulic fracturing technology has underpinned the development of unconventional reservoirs.Consequently,this has brought about a shift in the sequence of flow regimes,e.g.,the transient radial flow regime has been largely shortened by the lengthy transient linear flow regime due to the low permeability of unconventional reservoirs.Moreover,straight-line analysis(SLA),the simplest technique in rate transient analysis(RTA),is a fundamental and potent tool for swiftly extracting reservoir and hydraulic fracture information,estimating oil and gas reserves,and furnishing crucial initial data for subsequent historical matching processes.However,there is currently a dearth of review papers pertaining to a necessary guide of applying SLA in various transient linear flow(TLF)regimes and different unconventional reservoirs.Hence,this paper commences by elucidating the classification of TLF regimes,commonly used methods for recognizing flow regimes,and the diverse SLA methods used for different TLF regimes.Subsequently,it delves into a discussion of different modification techniques for variable rate/flowing pressure,gas phase,complex reservoir characteristics in unconventional reservoirs,and dynamic drainage area concepts etc.Furthermore,the application of SLA in specific domains,namely core analysis and the flowback period,is described.It culminates by surveying the advancements through an integration of novel technologies to enhance estimation accuracy.The paper also highlights certain drawbacks of current SLA technology and proposes new research directions.Ultimately,this paper would serve as an indispensable resource,offering foundational knowledge for the application of SLA in TLF to promote the production of global unconventional resources in a cost-effective and environmentally sustainable fashion in the face of a climate-resilient world. 展开更多
关键词 Unconventional reservoirs Straight-line analysis(SLA) Transient linear flow(TLF) Oil/gas reserves Hydraulic fracture information
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Advances in thermal-related analysis techniques for solid-state lithium batteries
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作者 Jianan Wang Kai Yang +8 位作者 Shiyi Sun Qianyue Ma Gong Yi Xin Chen Ze Wang Wei Yan Xinhua Liu Qiong Cai Yunlong Zhao 《InfoMat》 SCIE CSCD 2023年第4期77-116,共40页
Solid-state lithium batteries(SSLBs)have been broadly accepted as a promising candidate for the next generation lithium-ion batteries(LIBs)with high energy density,long duration,and high safety.The intrinsic non-flamm... Solid-state lithium batteries(SSLBs)have been broadly accepted as a promising candidate for the next generation lithium-ion batteries(LIBs)with high energy density,long duration,and high safety.The intrinsic non-flammable nature and electrochemical/thermal/mechanical stability of solid electrolytes are expected to fundamentally solve the safety problems of conventional LIBs.However,thermal degradation and thermal runaway could also happen in SSLBs.For example,the large interfacial resistance between solid electrolytes and electrodes could aggravate the joule heat generation;the anisotropic thermal diffusion could trigger the uneven temperature distribution and formation of hotspots further leading to lithium dendrite growth.Considerable research efforts have been devoted to exploring solid electrolytes with outstanding performance and harmonizing interfacial incompatibility in the past decades.There have been fewer comprehensive reports investigating the thermal reaction process,thermal degradation,and thermal runaway of SSLBs.This review seeks to highlight advanced thermal-related analysis techniques for SSLBs,by focusing particularly on multiscale and multidimensional thermal-related characterization,thermal monitoring techniques such as sensors,thermal experimental techniques imitating the abuse operating condition,and thermalrelated advanced simulations.Insightful perspectives are proposed to bridge fundamental studies to technological relevance for better understanding and performance optimization of SSLBs. 展开更多
关键词 characterization monitoring simulation solid-state batteries thermal technique
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Efficient Gait Analysis Using Deep Learning Techniques
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作者 K.M.Monica R.Parvathi 《Computers, Materials & Continua》 SCIE EI 2023年第3期6229-6249,共21页
Human Activity Recognition(HAR)has always been a difficult task to tackle.It is mainly used in security surveillance,human-computer interaction,and health care as an assistive or diagnostic technology in combination w... Human Activity Recognition(HAR)has always been a difficult task to tackle.It is mainly used in security surveillance,human-computer interaction,and health care as an assistive or diagnostic technology in combination with other technologies such as the Internet of Things(IoT).Human Activity Recognition data can be recorded with the help of sensors,images,or smartphones.Recognizing daily routine-based human activities such as walking,standing,sitting,etc.,could be a difficult statistical task to classify into categories and hence 2-dimensional Convolutional Neural Network(2D CNN)MODEL,Long Short Term Memory(LSTM)Model,Bidirectional long short-term memory(Bi-LSTM)are used for the classification.It has been demonstrated that recognizing the daily routine-based on human activities can be extremely accurate,with almost all activities accurately getting recognized over 90%of the time.Furthermore,because all the examples are generated from only 20 s of data,these actions can be recognised fast.Apart from classification,the work extended to verify and investigate the need for wearable sensing devices in individually walking patients with Cerebral Palsy(CP)for the evaluation of chosen Spatio-temporal features based on 3D foot trajectory.Case-control research was conducted with 35 persons with CP ranging in weight from 25 to 65 kg.Optical Motion Capture(OMC)equipment was used as the referral method to assess the functionality and quality of the foot-worn device.The average accuracy±precision for stride length,cadence,and step length was 3.5±4.3,4.1±3.8,and 0.6±2.7 cm respectively.For cadence,stride length,swing,and step length,people with CP had considerably high inter-stride variables.Foot-worn sensing devices made it easier to examine Gait Spatio-temporal data even without a laboratory set up with high accuracy and precision about gait abnormalities in people who have CP during linear walking. 展开更多
关键词 Human activity recognition neural networks gait analysis wearable sensors kinetic analysis cerebral palsy
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Analysis of TOPSIS techniques based on bipolar complex fuzzy N-soft setting and their applications in decision-making problems
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作者 Tahir Mahmood Ubaid ur Rehman +1 位作者 Zeeshan Ali Izatmand Haleemzai 《CAAI Transactions on Intelligence Technology》 SCIE EI 2023年第2期478-499,共22页
A novel model termed a bipolar complex fuzzy N-soft set(BCFN-SS)is initiated for tackling information that involves positive and negative aspects,the second dimension,and parameterised grading simultaneously.The theor... A novel model termed a bipolar complex fuzzy N-soft set(BCFN-SS)is initiated for tackling information that involves positive and negative aspects,the second dimension,and parameterised grading simultaneously.The theory of BCFN-SS is the generalisation of two various theories,that is,bipolar complex fuzzy(BCF)and N-SS.The invented model of BCFN-SS helps decision-makers to cope with the genuine-life dilemmas containing BCF information along with parameterised grading at the same time.Further,various algebraic operations,including the usual type of union,intersection,complements,and a few others types,are invented.Certain primary operational laws for BCFNSS are also invented.Moreover,a technique for order preference by similarity to the ideal solution(TOPSIS)approach is devised in the setting of BCFN-SS for managing strategic decision-making(DM)dilemmas containing BCFN-SS information.Keeping in mind the usefulness and benefits of the TOPSIS approach,two various types of TOPSIS approaches in the environment of BCFN-SS are devised and then a numerical example for exposing the usefulness of the devised TOPSIS approach is interpreted.To disclose the prominence and benefits of the devised work,the devised approaches with numerous prevailing work are compared. 展开更多
关键词 aggregation operators bipolar complex fuzzy N-soft sets decision-making similarity measures TOPSIS techniques
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