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Comparison between CBR and CA methods for estimating land use change in Dongguan, China

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Journal of Geographical Sciences 2012年第4期22卷 716-736页

作者： DU Yunyan GE Yong v.Chris LAKHAN SUN Yeran CAO Feng State Key Laboratory of Resources and Environmental Information System Institute of Geographic Science and Natural Resources ResearchCASBeijing 100101China Department of Earth and Environmental Sciences University of WindsorON N9B 3P4Canada

Many studies on land use change （LUC）, using different approaches and models, have yielded good results. Applications of these methods have revealed both advantages and limitations. However, LUC is a complex problem due to influences of many factors, and variations in policy and natural conditions. Hence, the characteristics and regional suitability of different methods require further research, and comparison of typical approaches is required. Since the late 1980s, CA has been used to simulate urban growth, urban sprawl and land use evolution successfully. Nowadays it is very popular in resolving the LUC estimating problem. Casebased reasoning （CBR）, as an artificial intelligence technology, has also been employed to study LUC by some researchers since the 2000s. More and more researchers used the CBR method in the study of LUC. The CA approach is a mathematical system constructed from many typical simple components, which together are capable of simulating complex behavior, while CBR is a problem-oriented analysis method to solve geographic problems, particularly when the driving mechanisms of geographic processes are not yet understood fully. These two methods were completely different in the LUC research. Thus, in this paper, based on the enhanced CBR model, which is proposed in our previous research （Duet aL 2009）, a comparison between the CBR and CA approaches to assessing LUC is presented. LUC in Dongguan coastal region, China is investigated. Applications of the improved CBR and the cellular automata （CA） to the study area, produce results demonstrating a similarity estimation accuracy of 89% from the improved CBR, and 70.7% accuracy from the CA. From the results, we can see that the accuracies of the CA and CBR approaches are both 〉70%. Although CA method has the distinct advantage in predicting the urban type, CBR method has the obvious tendency in predicting non-urban type. Considering the entire analytical process, the preprocessing workload in CBR is le

关键词： artificial intelligence case-based reasoning land use changes spatial relationship cellular automata Dongguan coastal region, China

An experimental investigation of wire electrical discharge machining of hot-pressed boron carbide

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Defence Technology（防务技术） 2015年第4期11卷 344-349页

作者： ravindranadh BOBBILI v.MADHU A.K.GOGIA Defence Metallurgical Research Laboratory

The present work discusses the experimental study on wire-cut electric discharge machining of hot-pressed boron *** effects of machining parameters,such as pulse on time(TON),peak current(IP),flushing pressure(FP) and spark voltage on material removal rate(MRR)and surface roughness(R_a) of the material,have been *** parameters are found to have an effect on the surface integrity of boron carbide machined *** rate of brass wire increases with rise in input energy in machining of hot-pressed boron *** surfaces of machined samples were examined using scanning electron microscopy(SEM).The influence of machining parameters on mechanism of MRR and R_a was *** was demonstrated that higher TON and peak current deteriorate the surface finish of boron carbide samples and result in the formation of large craters,debris and micro *** generation of spherical particles was noticed and it was attributed to surface tension of molten ***-ridges were also observed on the surface due to protrusion of molten material at higher discharge energy levels.

关键词：电火花加工碳化硼热压制实验扫描电子显微镜材料去除率表面粗糙度电火花线切割

Enhancing Air Quality Forecasts over Catalonia(Spain)Using Model Output Statistics

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Journal of Geoscience and Environment Protection 2015年第8期3卷 9-22页

作者： víctor Andrés Pérez raúl Arasa Bernat Codina Jesica Pinón Technical Department Meteosim S.L.BarcelonaSpain Department of Astronomy and Meteorology University of BarcelonaBarcelonaSpain

Model Output Statistics (MOS) is a well-known technique that allows improving outputs from numerical atmospheric models. In this contribution, we present the development of a MOS algorithm to improve air quality forecasts in Catalonia, a region in the northeast of Spain. These forecasts are obtained from an Eulerian coupled air quality modelling system developed by Meteosim. Nitrogen Dioxide (NO2), Particulate Matter (PM10) and Ozone (03) have been the pollutants considered and the methodology has been applied on statistical values of these pollutants according to regulatory levels. Four MOS algorithms have been developed, characterized by different approaches in relation with seasonal stratification and stratification according to the measurement stations considered. Algorithms have been compared among them in order to obtain a MOS that reduces the forecast uncertainties. Results obtained show that the best MOS designed increases the accuracy of NO2 maximum 1-h daily value forecast from 71% to 75%, from 68% to 81% in the case of daily values of PM10, and finally, the accuracy of O3 maximum 1-h daily value from 79% to 87%.

关键词： Air Quality Modelling Forecasting Model Output Statistics(MOS)

Photometric and Spectroscopic Studies for Two Magnetic-activity Contact Binaries:v724 And and QR Com

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Research in Astronomy and Astrophysics 2022年第11期22卷 51-60页

作者： Shuang Wang raul Meichel Huiyu Yuan Yuangui Yang School of Physics and Electronic Information Huaibei Normal UniversityHuaibei City 235000China Observatorio Astronomico Nacional Instituto de AstronomiaUniversidad Nacional Autonoma de MexicoApartado Postal 877EnsenadaB.C.22830Mexico

We presented new CCD photometry for two contact binaries,v724 And and QR Com,which were observed during the 2020–2022 observing *** using the Wilson–Devinney method,the photometric solutions were deduced from new observed data and TESS *** asymmetric light curves were modeled by a dark spot on the more massive *** indicate that the starspot may immigrate or disappear on the surface of the active *** the TESS observations of QR Com,it is discovered that the difference between light maxima exhibits a 29.5 day oscillation,which implies the continuous evolution of spot feathers on the timescale of sev.ral *** mass ratio and fill-out factor are q=2.308 and f=11.55% for v724 And,and q=0.624 and f=12.77% for QR Com,*** the(O-C)curve,the orbital period secularly decrease at a rate of d P/dt=-1.66×10^(-7)day yr^(-1)for v724 And and d P/dt=-3.98×10^(-7)day yr^(-1)for QR Com,which was interpreted by mass transfer from the more massive component to the less massive *** period decreasing,this kind of shallow-contact binaries,v724 And and QR Com,will evolve into the deep-contact configurations.

关键词： (stars:)binaries:eclipsing stars:fundamental parameters stars:low-mass

Total phenolic content,in vitro antioxidant activity and chemical composition of plant extracts from semiarid Mexican region

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Asian Pacific Journal of Tropical Medicine 2015年第2期8卷 104-111页

作者： Jorge E.Wong-Paz Juan C.Contreras-Esquivel raúl Rodríguez-Herrera María L.Carrillo-Inungaray Lluvia I.López Guadalupe v.Nevárez-Moorillón Cristóbal N.Aguilar Laboratory of Bioprocesses and Natural Products Food Research DepartmentSchool of ChemistryUniversidad Autónoma de CoahuilaSaltillo25280México Laboratory of Biochemistry Multidisciplinary Academic Unit-HuastecaUniversidad Autónoma de San Luis Potosí79060Cd.VallesS.L.P.Mexico Department of Microbiology School of ChemistryUniversidad Autónoma de Chihuahua31125 ChihuahuaMexico

Objective:To determine the extraction suitable conditions of total phenolic content(TPC) by heat-reflux system,antioxidant activities and HPLC characterization of the aqueous-ethanolic extracts of Jatropha dioica(***)(Dragon's blood).Flourensia cernua(***)(Tar bush).Eucalyptus camaldulensis(***)(Eucalyptus) and Turnera diffusa(***)(Damiana).Methods:TPC was evaluated by the well-known colorimetric assay using FolinCiocalteu *** antioxidant activities were assayed by three methods based on scavenging of DPPH,ABTS and by lipid oxidation *** chemical composition of the extracts obtained was subject to HPLC ***:TPC in the plant extracts ranged from 2.3 to14.12 mg gallic acid equivalents/g for *** and ***,*** plant extracts of ***,*** and *** showed similar strong antioxidant activities on scavenging of DPPH and lipid oxidation *** contrast,*** extracts had lowest potential antioxidant in three assays *** assay showed the presence of sev.ral phenolic compounds in the extracts ***:The results obtained suggest that ***,*** and *** are potential sources to obtain bioactive phenolic compounds with high antioxidant properties which can be used in the factories as antioxidant agents or for treatments in diseases.

关键词： Plant-extracts Polyphenols Natural antioxidants Mexican plants Heat-reflux system

Application of rough set-based analysis to extract spatial relationship indicator rules： An example of land use in Pearl River Delta

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Journal of Geographical Sciences 2011年第1期21卷 101-117页

作者： GE Yong CAO Feng DU Yunyan LAKHAN v. Chris WANG Yingjie LI Deyu State Key Laboratory of Resources and Environmental Information System Institute of Geographic Sciences and Natural Resources Research CAS Beijing 100101 China Department of Earth and Environmental Sciences University of Windsor ON N9B 3P4 Canada School of Computer & Information Technology of Shanxi University Taiyuan 030006 China

Spatial relations,reflecting the complex association between geographical phenomena and environments,are very important in the solution of geographical issues. Different spatial relations can be expressed by indicators which are useful for the analysis of geographical issues. Urbanization,an important geographical issue,is considered in this paper. The spatial relationship indicators concerning urbanization are expressed with a decision table. Thereafter,the spatial relationship indicator rules are extracted based on the application of rough set theory. The extraction process of spatial relationship indicator rules is illustrated with data from the urban and rural areas of Shenzhen and Hong Kong,located in the Pearl River Delta. Land use vector data of 1995 and 2000 are used. The extracted spatial relationship indicator rules of 1995 are used to identify the urban and rural areas in Zhongshan,Zhuhai and Macao. The identification accuracy is approximately 96.3%. Similar procedures are used to extract the spatial relationship indicator rules of 2000 for the urban and rural areas in Zhongshan,Zhuhai and Macao. An identification accuracy of about 83.6% is obtained.

关键词： rough set theory spatial relations spatial indicator rules land use change

Highly selective/enantioselective Pt-ReOx/C catalyst for hydrogenation of L-malic acid at mild conditions

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Journal of Energy Chemistry 2018年第3期27卷 903-912页

作者： Bair S.Bal'zhinimaev Eugene A.Paukshtis Alexey P.Suknev Nikita v.Makolkin Boreskov Institute of Catalysis SB ra5 Prospect Akademika Lavrentieva5Novosibirsk 630090Russia

The catalyst preparation strategy was based on a strict introduction sequence of rhenium and platinum precursors and their strong interaction with carbon support resulted in the formation of 0.5 nm Pt-Re Ox species of atomic dispersion, where platinum is metallic, while monolayer rhenium is partially oxidized（Re2＋）. The reaction kinetics was studied taking into account the process of L-malic acid association leading to the formation of inactive cyclic oligomeric species. High TOFs（ca. 50 h-1）, selectivities（ca. 99%）and stability of Pt-Re Ox/C catalysts in aqueous-phase hydrogenation of L-malic acid, which are close to those of the homogeneous pincer type complexes, were revealed at mild conditions（T = 90–130 ℃）. Taking into account that（i） hydrogenation reaction occurred 2–3 orders of magnitude faster than its racemization and（ii） association of L-malic acid dominates at low temperatures and in a concentrated solution,special reaction conditions that allow obtaining chemically and optically（ee 〉 99%） pure（S）-3-hydroxy-γ-butyrolactone and（S）-1,2,4-butanetriol were found. Basing on HAADF-STEM, EDX, XPS, and kinetic studies, the structure of active species and basic reaction pathways are proposed.

关键词： L-malic acid Hydrogenation Enantioselectivity Platinum Rhenium Atomic dispersion

Mechanism involved in the modulation of photoreceptor-specific cyclic nucleotidegated channel by the tyrosine kinase adapter protein Grb14

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Protein & Cell 2011年第11期2卷 906-917页

作者： vivek K.Gupta Ammaji rajala Karla K.Rodgers raju v.S.rajala Department of Ophthalmology University of Oklahoma Health Sciences CenterOklahoma CityOK 73104USA Department of Cell Biology University of Oklahoma Health Sciences CenterOklahoma CityOK 73104USA Department of Biochemistry and Molecular Biology University of Oklahoma Health Sciences CenterOklahoma CityOK 73104USA Dean A.McGee Eye Institute University of Oklahoma Health Sciences CenterOklahoma CityOK 73104USA

We recently found that growth factor receptor-bound(Grb)protein 14 is a novel physiological modulator of photoreceptor specific cyclic nucleotide-gated channel alpha subunit(CNGA1).Grb14 promotes the CNG channel closure through its ras-associating(ra)*** the current study we show that this ra domain-mediated inhibition of rod CNG channel is electrostatic in ***14 competes with cGMP for the CNGA1 binding pocket and electrostatically interacts with Arg^(559) through a negatively chargedβ-turn at its ra ***,the three Glu residues(180–182)in Grb14 are absolutely critical for electrostatic interaction with the cGMP binding pocket and resultant *** study also demonstrates that substitution of Lys^(140) for Ala or in combination with polyglutamte mutants of Grb14 results in a significantly reduced binding with *** results suggest that in addition to Glu^(180–182) and Lys^(140),other residues in Grb14 may be involved in the electrostatic interaction with *** ra domain is highly conserved among the members of Grb7 family of proteins,which includes Grb7,Grb10 and ***,only Grb14 is able to modulate the channel activity,but not Grb7 and *** together,it suggests the existence of a divergence in ra domains among the members of the Grb7 family.

关键词： growth factor receptor-bound protein 14(Grb14) ras-associating domain cyclic nucleotide gated channel rod outer segments tyrosine kinase signaling

Microstructure and Tensile Behavior of a Nano-Structured Al-Fe Based Alloy

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Journal of rare Earths 2004年第Z2期22卷 65-68页

作者： Won-Yong Kim Jae-Sung Park Mok-Soon Kim Tae-Yeub ra Advanced Materials R&D Center Korea Institute of Industrial Technology # 472Kajwa-dongSuh-guIncheon 404-254Korea School of Materials Science and EngineeringInha University # 253Yonghyun-dongNam-guIncheon 402-751Korea School of Materials Science and EngineeringInha University # 253Yonghyun-dongNam-guIncheon 402-751Korea Advanced Materials R&D CenterKorea Institute of Industrial Technology # 472Kajwa-dongSuh-guIncheon 404-254Korea

Room temperature deformation behavior of A1-8Fe-2Mo-2v-1Zr alloy produced by spray forming and subsequent warm-extrusion at 693 K and/or rolling at 423 K was investigated in terms of tensile test and microstructural *** the specimen processed by spray forming and warm extrusion, the microstructure consisting of equiaxed grains with the av.rage grain size of 500 nm in the matrix phase and uniformly dispersed fine intermetallic A13(Fe, Mo, v, Zr) and A16(Fe, Mo, v, Zr) phases less than 100 nm was characterized. It was revealed that subsequent warm rolling after warm extrusion promotes precipitation of a fine dispersoid from the supersaturated matrix phase. Warm rolling was found to be effective to increase the yield and tensile strength in the high strain rate regime. Elongation of the warm rolled specimen showed highe r value than extruded specimen over the whole strain rate region studied.

关键词： microstructure tensile deformation A1-Fe based alloy spray forming extrusion warm rolling precipitation strain rate sensitivity