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Accuracy Assessment of Land Use/Land Cover Classification Using Remote Sensing and GIS

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International journal of Geosciences 2017年第4期8卷 611-622页

作者： Sophia S. Rwanga j. m. Ndambuki Department of Civil Engineering Tshwane University Technology Pretoria South Africa Department of Civil Engineering Vaal University of Technology Vanderbijlpark South Africa Department of Civil Engineering Tshwane University of Technology Pretoria South Africa

Remote sensing is one of the tool which is very important for the production of Land use and land cover maps through a process called image classification. For the image classification process to be successfully, several factors should be considered including availability of quality Landsat imagery and secondary data, a precise classification process and user’s experiences and expertise of the procedures. The objective of this research was to classify and map land-use/land-cover of the study area using remote sensing and Geospatial Information System (GIS) techniques. This research includes two sections (1) Landuse/Landcover (LULC) classification and (2) accuracy assessment. In this study supervised classification was performed using Non Parametric Rule. The major LULC classified were agriculture (65.0%), water body (4.0%), and built up areas (18.3%), mixed forest (5.2%), shrubs (7.0%), and Barren/bare land (0.5%). The study had an overall classification accuracy of 81.7% and kappa coefficient (K) of 0.722. The kappa coefficient is rated as substantial and hence the classified image found to be fit for further research. This study present essential source of information whereby planners and decision makers can use to sustainably plan the environment.

关键词： Accuracy assessment Geographic Information Systems (GIS) Land Use Land Cover (LULC) Remote Sensing

BEA沸石后合成金属(Sn,Zr,Hf)改性:结合Lewis和Bronsted酸性进行级联催化

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Chinese journal of Catalysis 2023年第12期55卷 200-215页

作者： Peerapol Pornsetmetakul Ferdy j.A.G.Coumans Rim C.j.van de Poll Anna Liutkova Duangkamon Suttipat Brahim mezari Chularat Wattanakit Emiel j.m.Hensen 泰国科学与技术研究院能源科学与工程学院泰国埃因霍温理工大学化学工程系无机材料与催化实验荷兰

Sn,Zr和Hf等Lewis酸性金属中心改性的沸石是许多生物炼制相关反应(如碳水化合物异构化和呋喃meerwein-Pondorf-Verley(mPV)还原)中有应用前景的催化剂.在大孔BEA沸石框架中固载上述金属离子得到的催化剂性能良好.然而,制备该类催化剂通... 详细信息

Sn,Zr和Hf等Lewis酸性金属中心改性的沸石是许多生物炼制相关反应(如碳水化合物异构化和呋喃meerwein-Pondorf-Verley(mPV)还原)中有应用前景的催化剂.在大孔BEA沸石框架中固载上述金属离子得到的催化剂性能良好.然而,制备该类催化剂通常需采用昂贵的有机金属前体,并且需要经历多步制备过程.本文开发了一种简易的固态研磨法,采用简单的无机金属前体,在脱铝BEA沸石中成功掺入了高度分散的、高金属含量(Si/m比为50-75)的孤立Sn,Zr和Hf.在样品焙烧前,采用甲醇处理去除过量的金属,可使孤立金属位点高含量、有效地掺杂在BEA框架中.在改性的BEA沸石中,Lewis酸位点来自于开放的Sn,Zr和Hf孤立金属离子位点;Sn改性的BEA上Lewis酸位点还包括封闭的Sn位点,但开放的Sn位点表现出最高的Lewis酸性.Br?nsted酸性来自于受开放金属位点Lewis酸性金属离子摄动的硅羟基以及与开放金属位点相连的羟基.Sn,Zr,Hf改性的BEA沸石在肉桂醛级联还原醚化反应中表现出较好的催化活性.以异丙醇为溶剂,肉桂醛先在Lewis酸位点上发生mPV还原生成肉桂醇;随后,肉桂醇在Br?nsted酸位点发生醚化反应生成肉桂基丙基醚.其中,Sn改性的BEA沸石表现出最高的催化活性,这是因为其具有最强的Lewis酸性,这对第一步mPV反应至关重要.此外,将本研究中Sn改性优化固态离子交换法用于对不同形貌BEA沸石进行改性以提高其催化性能,结果表明,BEA沸石多级孔结构进一步有利于级联还原醚化反应.

关键词：分子筛 BEA沸石嫁接金属形态酸性

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锰、铬、钼对共析钢中奥氏体等温转变的影响

热处理技术与装备 1987年第3期25卷 32-37页

作者： Y.j.park F.B.Fletcher 曾科军中南工业大学

用膨胀仪测定了一系列含0.75%C,0.28%Si,0.43～0.91%mn,0～0.76%Cr和0～0.34%mo的共析合金钢的等温转变图。通过对等温转变图数据的多元线性回归分析,评定了mn,Cr和mo对这些共析钢相变行为的影响。回归分析表明mo在高温区(650～500℃)... 详细信息

用膨胀仪测定了一系列含0.75%C,0.28%Si,0.43～0.91%mn,0～0.76%Cr和0～0.34%mo的共析合金钢的等温转变图。通过对等温转变图数据的多元线性回归分析,评定了mn,Cr和mo对这些共析钢相变行为的影响。回归分析表明mo在高温区(650～500℃)抑制奥氏体分解的能力最大,而Cr则在中温区(550～500℃)、mn在低温区(350～300℃)对奥氏体分解有最大抑制效应。研究结果表明,mo对珠光体形成的抑制作用比它对贝氏体形成的抑制作用大得多,而mn即抑制珠光体转变,也抑制贝氏体转变。

关键词：共析钢合金元素钢中奥氏体 γ固溶体金相相组成等温转变图

Leveraging off higher plant phylogenetic insights for antiplasmodial drug discovery

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Natural Products and Bioprospecting 2023年第1期13卷 382-399页

作者： Phanankosi moyo Luke Invernizzi Sephora m.mianda Wiehan Rudolph Warren A.Andayi mingxun Wang Neil R.Crouch Vinesh j.m.haraj Biodiscovery Center Department of ChemistryFaculty of Natural and Agricultural SciencesUniversity of PretoriaPrivate Bag X 20HatfieldPretoria 0028South Africa Department of Physical and Biological Sciences Murang’a University of TechnologyMurang’aKenya Computer Science and Engineering University of California Riverside900 University AveRiversideCA 92521USA Biodiversity Research and monitoring Directorate South African National Biodiversity InstituteBerea RoadP.O.Box 52099Durban 4007South Africa School of Chemistry and Physics University of KwaZulu-NatalDurban 4041South Africa

The antimalarial drug-resistance conundrum which threatens to reverse the great strides taken to curb the malaria scourge warrants an urgent need to find novel chemical scaffolds to serve as templates for the development of new antimalarial *** represent a viable alternative source for the discovery of unique potential antiplasmodial chemical *** expedite the discovery of new antiplasmodial compounds from plants,the aim of this study was to use phylogenetic analysis to identify higher plant orders and families that can be rationally prioritised for antimalarial drug *** queried the Pubmed database for publications documenting antiplasmodial properties of natural compounds isolated from higher ***,we manually collated compounds reported along with plant species of origin and relevant pharmacological *** systematically assigned antiplasmodial-associated plant species into recognised families and orders,and then computed the resistance index,selectivity index and physicochemical properties of the compounds from each taxonomic *** the generated phylogenetic trees and the biological data of each clade allowed for the identification of 3‘hot’plant orders and *** top 3 ranked plant orders were the(i)Caryophyllales,(ii)Buxales,and(iii)*** top 3 ranked plant families were the(i)Ancistrocladaceae,(ii)Simaroubaceae,and(iii)*** highly active natural compounds(IC_(50)≤1μm)isolated from these plant orders and families are structurally unique to the‘legacy’antimalarial *** study was able to identify the most prolific taxa at order and family rank that we propose be prioritised in the search for potent,safe and drug-like antimalarial molecules.

关键词： Natural products Plants Phylogenetics malaria Drug-resistance ‘Hot’plants

柱状扰动体引起圆柱谐振腔共振频率偏移的数值模拟

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地球物理学报 2005年第2期48卷 445-451页

作者： Harris j.m.徐德龙王秀明宋延杰丛健生陈德华 Department of Geophysics Stanford University CA 94306 USA 黑龙江省大庆石油学院地球物理系 CSIRO Petroleum P.O. Box1130 Technology Park Bentley WA6102 Australia

基于微扰理论,研究了内部存在一个同轴圆柱扰动体时圆柱谐振腔共振频率的偏移问题.其中,圆柱谐振腔的边侧面是刚性的,上下底面应力自由.经过推导,得出了圆柱扰动体存在时谐振腔的声势与共振频率的表达式.在此基础上,分析了谐振腔与圆柱... 详细信息

基于微扰理论,研究了内部存在一个同轴圆柱扰动体时圆柱谐振腔共振频率的偏移问题.其中,圆柱谐振腔的边侧面是刚性的,上下底面应力自由.经过推导,得出了圆柱扰动体存在时谐振腔的声势与共振频率的表达式.在此基础上,分析了谐振腔与圆柱扰动体各种参数对谐振腔共振频率的影响.数值模拟结果表明,谐振腔的共振频率受扰动体在谐振腔中的位置影响较大.圆柱谐振腔的共振频率在圆柱扰动体居中时是最大值,并且其共振频率对扰动体的声速敏感;当扰动体在谐振腔两端时,谐振腔共振频率是最小值,并且其对扰动体的密度敏感.最后,通过数值模拟结果和实验测量结果之间的对比,发现两者的基本变化趋势是吻合的.

关键词：共振声谱共振频率偏移微扰理论岩石物理

mRI与68Ga-PSmA-11 PET/mRI的PSmA-PET联合评估前列腺癌复发

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国际医学放射学杂志 2024年第5期 623-623页

作者： K.jannusch N.m.Bruckmann j.m.rawitz m.Boschheidgen H.H.Quick K.Herrmann 张昕怡苗彦

目的探讨mRI与68Ga-PSmA-11 PET/mRI的PET评估前列腺癌（PCa）生化复发分期的优势。方法本回顾性研究纳入PCa生化复发并进行全身增强68Ga-PSmA-11

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Determination of the maximum allowable gas pressure for an underground gas storage salt cavern——A case study of jintan,China

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journal of Rock mechanics and Geotechnical Engineering 2019年第2期11卷 251-262页

作者： Tongtao Wang jianjun Li Gang jing Qingqing Zhang Chunhe Yang j.j.K.Daemen State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil MechanicsChinese Academy of Sciences Department of Gas Storage Project West-East Gas Pipeline CompanyPetroChina mackay School of Earth Sciences and Engineering University of Nevada

Increasing the allowable gas pressure of underground gas storage(UGS) is one of the most effective methods to increase its working gas capacity. In this context, hydraulic fracturing tests are implemented on the target formation for the UGS construction of jintan salt caverns, China, in order to obtain the minimum principal in situ stress and the fracture breakdown pressure. Based on the test results, the maximum allowable gas pressure of the jintan UGS salt cavern is calibrated. To determine the maximum allowable gas pressure, KING-1 and KING-2 caverns are used as examples. A three-dimensional(3D)geomechanical model is established based on the sonar data of the two caverns with respect to the features of the target formation. New criteria for evaluating gas penetration failure and gas seepage are proposed. Results show that the maximum allowable gas pressure of the jintan UGS salt cavern can be increased from 17 mPa to 18 mPa(i.e. a gradient of about 18 k Pa/m at the casing shoe depth). Based on numerical results, a field test with increasing maximum gas pressure to 18 mPa has been carried out in KING-1 cavern. microseismic monitoring has been conducted during the test to evaluate the safety of the rock mass around the cavern. Field monitoring data show that KING-1 cavern is safe globally when the maximum gas pressure is increased from 17 mPa to 18 mPa. This shows that the geomechanical model and criteria proposed in this context for evaluating the maximum allowable gas pressure are reliable.

关键词： Underground gas storage(UGS)salt cavern In situ stress testing maximum gas pressure Gas penetration failure microseismic monitoring

Aseismic smart building isolation systems under multi-level earthquake excitations： Part II, energy-dissipation and damage reduction

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Frontiers of Structural and Civil Engineering 2015年第3期9卷 297-306页

作者： min-Ho CHEY j. Geoffrey CHASE john B. mANDER Athol j. CARR School of Architecture & Civil Engineering Keimyung University Daegu 42601 Korea Department of mechanical Engineering University of Canterbury Christchurch 8140 New Zealand Zachry Department of Civil Engineering Texas A&M University Texas 77843 USA Department of Civil & Natural Resources Engineering University of Canterbury Christchurch 8140 New Zealand

Based on the performance results of the previously suggested smart building isolation systems （lst companion paper）, this following study verifies the control effects of the systems from the view point of energy dissipation and damage level metrics. Several different model cases of the strategically isolated multi-story building structures utilizing passive dampers and semi-active resettable devices are analyzed and the energy-based target indices are compared. Performance comparisons are conducted on statistically calculated story/structural hysteretic energy and story/structural damage demands over realistic suites of earthquake ground motion records, representing seismic excitations of specific return period probability. Again, the semi-active solutions show significant promise for applications ofresettable device, offering advantages over passive systems in the consistent damage reductions. The specific results of this study include the identification of differences in the mechanisms by which smart building isolation systems remove energy, based on the differences in the devices used. Less variability is also seen for the semi-active isolation systems, indicating an increased robustness.

关键词： smart building isolation story and structural energy-dissipation damage assessment

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Optimising mesh size with escape gaps in a dual-species portunid-trap fishery

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Aquaculture and Fisheries 2020年第6期5卷 308-316页

作者： matt K.Broadhurst Daniel j.Tolhurst Brian Hughes Vincent Raoult Timothy m.Smith Troy F.Gaston NSW Department of Primary Industries Fisheries Conservation Technology UnitNational Marine Science CentrePO Box 4321Coffs HarbourNSW2450Australia marine and Estuarine Ecology Unit School of Biological SciencesUniversity of QueenslandBrisbaneQLD4072Australia The Roslin Institute and Royal(Dick)School of Veterinary Studies University of EdinburghEaster BushMidlothianEH259RGUnited Kingdom Hunter Local Land Services PO Box 440TareeNSW2430Australia School of Environmental and Life Sciences University of NewcastleOurimbahNSW2258Australia

In south-eastern Australia,the same baited,round traps(comprising 50–57-mm mesh netting)are used to target giant mud,Scylla serrata and blue swimmer crabs,Portunus armatus in spatially separated *** fisheries are characterised by the common,problematic discarding of undersized portunids(mm carapace length;CL for *** and ***)and fish(yellowfin bream,Acanthopagrus australis).This poor selectivity was addressed here in two experiments assessing the utility of(1)traps partially or completely covered in larger mesh(91 mm to match the minimum legal size of the smaller ***),and then(2)any cumulative benefits of fitting species-specific escape *** experiment 1,there were no differences among catches of legal-sized portunids associated with either partial,or complete trap coverage with larger *** of mesh coverage,both designs of 91-mm traps also retained significantly fewer(by up to 42%)undersized *** and *** experiment 2,replicate traps completely covered in 91-mm mesh were tested against conventional traps comprising 56-mm mesh,and traps with the same mesh sizes,but also three escape gaps configured for either ***(46×120 mm)or ***(36×120 mm)(*** treatments in total).All modified traps maintained catches of legal-sized ***,and only the 91-mm traps with escape gaps caught fewer legal-sized *** undersized ***,*** and ***(mean catches reduced by up to 49%)were retained in all larger-meshed than small-meshed traps,and in all of those traps with escape gaps(by up to 95%)than *** there were no significant cumulative benefits of escape gaps in largermeshed traps(measured by a statistical interaction),there was a trend of fewer unwanted catches *** data support configuring portunid traps with mesh sizes matching the morphology of the smallest legal-sized target ***,simply retroactively fitting escape gaps in existing,smaller-m

关键词： Bycatch Escape gap mesh size Portunid