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Trees of panama: A complete checklist with every geographic range

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Forest Ecosystems 2020年第3期7卷 526-538页

作者： Richard Condit Salomón Aguilar Rolando pérez Morton Arboretum 4100 Illinois Rte.53Lisle60532ILUSA Smithsonian Tropical Research Institute Panama CityPanama

Background Central America is one of the most diverse floristic provinces in the world,but comprehensive plant lists for the region are incomplete and need frequent *** geographic ranges of individual species are seldom *** detailed forest inventory plots of panama thus lack a global geographic *** order to provide one,we assembled a thoroughly vetted checklist of all tree species of panama,along with an estimate of each one’s range size based on published specimen *** 1)panama has 3043 tree species in 141 families and 752 genera;57.6%were≥10 m tall and 16.9%were 3-5 m tall.2)The widest ranges were>1.5×107 km2,covering the entire neotropics and reaching>30∘latitude;12.4%of the species had ranges exceeding 107 *** median range was 6.9×105 km2.3)At the other extreme,16.2%of the species had a rangen suggesting endangered status.4)Range size increased with a tree species’height and varied significantly among families.5)Tree census plots,where we mapped and measured all individuals,captured 27.5%of the tree species,but a biased selection relative to range size;only 4.5%of the species in plots had rangespanama,based on rigorous criteria aimed at matching plot censuses,is 20%larger than *** recording species’maximum heights,we allow comparisons with other regions based on matching definitions,and the range sizes provide a quantitative basis for assessing extinction *** next goal is to merge population density from plot censuses to add rigor to predictions of extinction risk of poorly-studied tropical tree species.

关键词： red Trees of panama A complete checklist with every geographic range

Stochastic Ranking Improved Teaching-Learning and Adaptive Grasshopper Optimization Algorithm-Based Clustering Scheme for Augmenting network Lifetime in WSns

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China Communications 2024年第9期21卷 159-178页

作者： n Tamilarasan SB Lenin p Mukunthan nC Sendhilkumar Department of Electronics and Communications Engineering Sri Indu College of Engineering and TechnologyHyderabadTelanganaIndia Department of Electronics and Communications Engineering Sri Manakula Vinayagar Engineering CollegePondicherryIndia

In Wireless Sensor networks(WSns),Clustering process is widely utilized for increasing the lifespan with sustained energy stability during data *** clustering protocols were devised for extending network lifetime,but most of them failed in handling the problem of fixed clustering,static rounds,and inadequate Cluster Head(CH)selection criteria which consumes more *** this paper,Stochastic Ranking Improved Teaching-Learning and Adaptive Grasshopper Optimization Algorithm(SRITL-AGOA)-based Clustering Scheme for energy stabilization and extending network *** SRITL-AGOA selected CH depending on the weightage of factors such as node mobility degree,neighbour's density distance to sink,single-hop or multihop communication and Residual Energy(RE)that directly influences the energy consumption of sensor *** specific,Grasshopper Optimization Algorithm(GOA)is improved through tangent-based nonlinear strategy for enhancing the ability of global *** the other hand,stochastic ranking and violation constraint handling strategies are embedded into Teaching-Learning-based Optimization Algorithm(TLOA)for improving its exploitation ***,SR and VCH improved TLOA is embedded into the exploitation phase of AGOA for selecting better CH by maintaining better balance amid exploration and *** results confirmed that the proposed SRITL-AGOA improved throughput by 21.86%,network stability by 18.94%,load balancing by 16.14%with minimized energy depletion by19.21%,compared to the competitive CH selection approaches.

关键词： Adaptive Grasshopper Optimization Algorithm(AGOA) Cluster Head(CH) network lifetime Teaching-Learning-based Optimization Algorithm(TLOA) Wireless Sensor networks(WSns)

Assessing tourism sustainability in hill towns:Case study of Shimla,India

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Journal of Mountain Science 2020年第9期17卷 2241-2261页

作者： Rukhsana n.BADAR Sarika p.BAHADURE Department of Architecture and planning Visvesvaraya National Institute of TechnologySouth Ambazari RoadNagpur 440010MaharashtraIndia

Hill towns form a popular niche in tourism *** are renowned for their natural beauty and distinctive cultural *** development can lead to a loss in opportunity to access the potential of these resources or cause their *** decisions need to adopt a sustainable approach that balances tourism growth with the preservation of the natural and cultural *** present research details a comprehensive assessment tool to study the sustainability of tourism in hill towns with a focus on Shimla,a popular hill destination in *** tool specifies seven dimensions of sustainable tourism;1)Tourism Assets;2)Tourism Activity;3)Tourism Related Linkages;4)Tourism Related Leakages;5)Environmental and Social Sustainability;6)Infrastructure;and 7)*** data were collected through questionnaire surveys of local households and arriving *** survey is conducted to map built-environment and *** data were gathered from government reports and scholarly articles.A framework of indicators and sub-indicators was developed to analyze the data at two levels–city and *** the appraisal of the city provides an overall view of the performance of the tourism industry,at the ward level a comparative analysis was carried out to reveal sector related potentials and *** study reveals the imbalanced tourismconcentration in the core of the city as compared to other wards and the gap between tourist potential and infrastructure *** are addressed through planning recommendations for more balanced development with a focus on *** research helps develop a framework which paves way to sustainable tourism development in Indian hill towns.

关键词： Sustainable tourism Hill towns Tourism assets Tourism linkages Tourism leakages

Compressional origin of the Aegean Orogeny,Greece

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Geoscience Frontiers 2022年第2期13卷 383-404页

作者： Michael p.Searle Thomas n.Lamont Dept Earth Sciences Oxford UniversitySouth Parks RoadOxfordOX13ANUK School of Earth and Environmental Sciences University of St AndrewsSt AndrewsKY169ALUK

The Aegean Sea area is thought to be an actively extending back-arc region,north of the present day Hellenic volcanic arc and north-dipping subduction zone in the Eastern *** area shows extensive normal faulting,ductile‘extensional’shear zones and extensional S-C fabrics throughout the islands that have previously been related to regional Aegean extension associated with slab rollback on the Hellenic Subduction *** this paper,we question this interpretation,and suggest the Cenozoic geodynamic evolution of the Aegean region is associated with a Late Cretaceous-Eocene nE-dipping subduction zone that was responsible for continentcontinent collision between Eurasia and Adria-Apulia/*** of eclogite and blueschist facies rocks in the Cyclades and kyanite-sillimanite grade gneisses in the naxos core complex have pressures that are far greater than could be accounted for purely by lithospheric extension and isostatic *** identify four stages of crustal shortening that affected the region prior to regional lithospheric extension,herein called the Aegean *** orogeny followed a classic Wilson cycle from early ophiolite obduction(ca.74 Ma)onto a previously passive continental margin,to attempted crustal subduction with Hp eclogite and blueschist facies metamorphism(ca.54-45 Ma),through crustal thickening and regional kyanite-sillimanite grade Barroviantype metamorphism(ca.22-14 Ma),to orogenic collapse(periods of‘extensional’fabrics relate to:(1)Exhumation of blueschists and eclogite facies rocks showing tight-isoclinal folds and top-nE,base-SW fabrics,recording return flow along a subduction channel in a compressional tectonic setting(ca.50-35 Ma).(2)Extensional fabrics within the core complexes formed by exhumation of kyanite-and sillimanite gneisses showing thrust-related fabrics at the base and‘extensional’fabrics along the top(ca.18.5-14 Ma).(3)Regional ductile-brittle‘extensional’fabrics and low-angle

关键词： Cyclades Ophiolite High-pressure metamorphism Core complex Compressional tectonics

Characterization and Effect of Using Mahua Oil Biodiesel as Fuel in Compression Ignition Engine

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Journal of Thermal Science 2009年第4期18卷 382-384页

作者： n.Kapilan T.p.Ashok Babu R.p.Reddy Department of Mechanical Engineering NITKSurathkal

There is an increasing interest in India, to search for suitable alternative fuels that are environment friendly. Thisled to the choice of Mahua Oil (MO) as one of the main alternative fuels to diesel. In this investigation, MahuaOil Biodiesel (MOB) and its blend with diesel were used as fuel in a single cylinder, direct injection and compressionignition engine. The MOB was prepared from MO by transesterification using methanol and potassiumhydroxide. The fuel properties of MOB are close to the diesel and confirm to the ASTM standards. From the enginetest analysis, it was observed that the MOB, B5 and B20 blend results in lower CO, HC and smoke emissionsas compared to diesel. But the B5 and B20 blends results in higher efficiency as compared to MOB. HenceMOB or blends of MOB and diesel (B5 or B20) can be used as a substitute for diesel in diesel engines used intransportation as well as in the agriculture sector.

关键词： Alternative fuel mahua oil biodiesel engine performance

Optimization of assembly line balancing using genetic algorithm

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Journal of Central South University 2015年第10期22卷 3957-3969页

作者： n.Barathwaj p.Raja S.Gokulraj School of Mechanical Engineering SASTRA University Rane (Madras) Ltd. Deputy Manager (Manufacturing Engineering System Design Department)

In a manufacturing industry, mixed model assembly line(MMAL) is preferred in order to meet the variety in product demand. MMAL balancing helps in assembling products with similar characteristics in a random fashion. The objective of this work aims in reducing the number of workstations, work load index between stations and within each station. As manual contribution of workers in final assembly line is more, ergonomics is taken as an additional objective function. Ergonomic risk level of a workstation is evaluated using a parameter called accumulated risk posture(ARp), which is calculated using rapid upper limb assessment(RULA) check sheet. This work is based on the case study of an MMAL problem in Rane(Madras) Ltd.(India), in which a problem based genetic algorithm(GA) has been proposed to minimize the mentioned objectives. The working of the genetic operators such as selection, crossover and mutation has been modified with respect to the addressed MMAL problem. The results show that there is a significant impact over productivity and the process time of the final assembled product, i.e., the rate of production is increased by 39.5% and the assembly time for one particular model is reduced to 13 min from existing 18 min. Also, the space required using the proposed assembly line is only 200 m2 against existing 350 m2. Further, the algorithm helps in reducing workers fatigue(i.e., ergonomic friendly).

关键词： optimization line balancing genetic algorithm product family assembly line

A machine learning approach for accelerated design of magnesium alloys. part A:Alloy data and property space

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Journal of Magnesium and Alloys 2023年第11期11卷 3620-3633页

作者： M.Ghorbani M.Boley p.n.H.nakashima n.Birbilis Department of Materials Science and Engineering Monash UniversityVIC3800Australia Faculty of Information Technology Monash UniversityVIC3800Australia College of Engineering and Computer Science Australian National UniversityACT2601Australia Faculty of Engineering Science and the Built EnvironmentDeakin UniversityVIC3125Australia

Typically, magnesium alloys have been designed using a so-called hill-climbing approach, with rather incremental advances over the past century. Iterative and incremental alloy design is slow and expensive, but more importantly it does not harness all the data that exists in the field. In this work, a new approach is proposed that utilises data science and provides a detailed understanding of the data that exists in the field of Mg-alloy design to date. In this approach, first a consolidated alloy database that incorporates 916 datapoints was developed from the literature and experimental work. To analyse the characteristics of the database, alloying and thermomechanical processing effects on mechanical properties were explored via composition-process-property matrices. An unsupervised machine learning(ML) method of clustering was also implemented, using unlabelled data, with the aim of revealing potentially useful information for an alloy representation space of low dimensionality. In addition, the alloy database was correlated to thermodynamically stable secondary phases to further understand the relationships between microstructure and mechanical properties. This work not only introduces an invaluable open-source database, but it also provides, for the first-time data, insights that enable future accelerated digital Mg-alloy design.

关键词： Magnesium Alloy design Mg-alloy database Data analysis Data visualisation Unsupervised machine learning

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3D tomographic analysis of equatorial plasma bubble using GnSS-TEC data from Indonesian GnSS network

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Earth and planetary physics 2025年第1期9卷 127-136页

作者： Ihsan naufal Muafiry prayitno Abadi Teguh n.pratama Dyah R.Martiningrum Sri Ekawati Yuandhika GWismaya Febrylian FChabibi Gatot Hpramono Research Center for Climate and Atmosphere Indonesian National Research and Innovation Agency(BRIN)BandungIndonesia Indonesian Geospatial Information Agency(BIG) JakartaIndonesia Dept.of physics Faculty of ScienceUniversiti Teknologi MalaysiaJohor BahruMalaysia Dept.Earth planet Sci. Hokkaido UniversitySapporoJapan School of Electrical Engineering Telkom UniversityBandungIndonesia

Equatorial plasma Bubbles(EpBs)are ionospheric irregularities that take place near the magnetic *** most commonly occur after sunset during the equinox months,although they can also be observed during other *** phenomenon significantly disrupts radio wave signals essential to communication and navigation *** national network of Global navigation Satellite System(GnSS)receivers in Indonesia(>30°longitudinal range)provides an opportunity for detailed EpB *** explore this,we conducted preliminary 3D tomography of total electron content(TEC)data captured by GnSS receivers following a geomagnetic storm on December 3,2023,when at least four EpB clusters occurred in the Southeast Asian *** and extracted TEC depletion with a 120-minute running average were then used as inputs for a 3D tomography *** 2D spatial distribution consistently captured the four EpB clusters over *** tomography results were validated through a classical checkerboard test and comparisons with other ionospheric data sources,such as the Global Ionospheric Map(GIM)and International Reference Ionosphere(IRI)*** of the results demonstrates the capability of the Indonesian GnSS network to measure peak ionospheric *** findings highlight the potential for future three-dimensional research of plasma bubbles in low-latitude regions using existing GnSS networks,with extensive longitudinal coverage.

关键词： EpB Indonesian GnSS network 3D tomography

Cadmium sorption by sodium and thiourea-modified zeolite-rich tuffs

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Journal of Environmental Sciences 2017年第2期29卷 39-48页

作者： perfecto Barragán p M.Guadalupe Macedo M Maria T.Olguín Instituto Tecnologico de Toluca Laboratorio de Investigacion en Ingenieria Ambiental.Av.Tecnologico S/NColonia Ex-Rancho La VirgenMetepecEstado de Meico CP.52140Mexico Instituto national de Investigaciones nucleares Departamento de QuimicaA.P.18-1027Col.EseandonDelegacion Miguel Hidalgo C.P.11801Mexico

In the present investigation, two zeolite-rich tuffs from Guaymas and El Cajon（State of Sonora）, which were conditioned with a sodium chloride solution and subsequently modified with a thiourea solution, were chosen to evaluate the removal of Cd from aqueous systems. The zeolitic materials were characterized by scanning electron microscopy and X-ray diffraction. The surface area was also determined. The experiments were performed in a batch system, and the influences of p H, contact time between phases, and the concentration of Cd in the solution on the adsorption by sodium or thiourea-modified zeolite-rich tuff were investigated. It was found that the efficiency of Cd ion removal from aqueous solutions is influenced by the p H of the aqueous systems. The Cd adsorption kinetic data were well fitted to a pseudo-second-order model in all cases. The Langmuir and Langmuir–Freundlich isotherms adequately described the Cd sorption behavior by the zeolite from El Cajon pretreated with na Cl and the zeolite from Guaymas modified with thiourea, respectively.

关键词： Cadmium Zeolite-rich-tuff Sorption Kinetics Isotherms