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International Journal of Mining science and Technology 2014年第1期24卷 75-80页

作者： Vinoth s. Ajay Kumar L. Department of Mining Engineering College of Engineering GuindyAnna University

This paper outlines the results obtained from real time microseismic monitoring of an opencast coal mine in south *** objective of the study is to investigate the stress changes within the rockmass along the slope due to underground mine development operation and their impact on the stability of the highwall *** installed microseismic systems recorded the seismic triggerings down toà2 moment *** general,most of the events recorded during the monitoring period are weak in seismic *** study adopts a simple and more reliable tool to characterize the seismically active zone for assessing the stability of the highwall in real *** impact of underground working on the slope is studied on the basis of the seismic event impact contours and seismic *** the monitoring period,it is observed that the intensity of the overall microseismic activity along the slope due to the mine development operations did not cause any adverse impact on the highwall stability.

关键词： seismic monitoring Induced seismicity seismic clusters slope stability Opencast mining

Improving Qos Using Mobility-Based Optimized Multipath Routing Protocol in MANET

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Computer systems science & Engineering 2023年第7期46卷 1169-1181页

作者： s.J.sangeetha T.Rajendran Department of Computer science Periyar UniversitySalem636011India PG and Research Department of Computer science Government Arts and Science CollegeKangeyam638108India

Mobile Ad-hoc Networks(MANETs)connect numerous nodes to communicate data from the sender node to the target *** to the lack of an infrastructure network,mobile nodes communicate through wireless without an access *** does not have a centralized controller and has a dynamic network topology,which increases link failure and energy consumption resulting in excessive path delay,loss of Quality of service(Qos),and reduced throughput during data *** is a significant problem when the Qos of the link carrying the data is *** is one of the vital challenges of MANET due to the very dynamic and distributed nature of *** article introduces a Mobility-Based Optimized Multipath Routing Protocol(MBOMRP)and an Efficient Reliable Link-state Transmission(ERLsT)algorithm to overcome these *** proposed Mobility-Based Optimized Multipath Routing Protocol(MBOMRP)is utilized for route discovery and maintenance to efficiently avoid traffic and sleeping *** algorithm is used for efficient data transmission to increase Qos measurement parameters like throughput,Packet Delivery Ratio(PDR),and minimize the latency *** proposed MBOMRP-ERLsT algorithm improves data communication network lifetime,avoids link failures,and provides efficient results compared with previous algorithms.

关键词： MANET Qos link failure improve data communication avoid traffic network lifetime MBOMRP-ERLsT

An improved approach for the production of satellite-based geospatialreference imagery

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International Journal of Digital Earth 2008年第2期1卷 221-239页

作者： J.R.Gibson s.Nedelcu Canada Centre for Remote sensing 588 Booth Street OttawaOntarioCanada

An innovative and practical satellite image product is described that is ideal for applications in Northern Canada because of its wide area coverage and mappingquality *** product is generated from a new procedure developed at the Canada Centre for Remote sensing(CCRs)for processing Landsat 7 imagery,and by extension,imagery from other Earth Observation *** working with multiple satellite passes,each containing the equivalent of multiple scenes,the new procedure could dramatically reduce the turn-around time for generating georeferenced image products,and also increase their geometric and radiometric accuracy compared to those produced by the current *** objective of the process has been to generate satellite image mosaics covering large areas(e.g.>500000 km^(2))with uniformly distributed errors at sub-pixel *** paper discusses the theoretical basis of a photogrammetric adjustment for satellite imagery and the results obtained from several *** process is generic,involving a sensor model,a satellite orbit model and ground control information;thus it may be easily adapted to any satellite that allows for repeat coverage with overlapping *** performing an adjustment to correct the satellite position and attitude data prior to the production of orthoimage products,it is possible to create a mosaic with a single resampling process which minimises both the radiometric and geometric resampling *** results from three separate tests are presented,along with a discussion of the procedures that were followed in each *** three tests have successfully demonstrated that sub-pixel sample size errors may be consistently obtained over large areas.A by-product process developed to support the measurement of ground control point coordinates for the satellite adjustment was the automatic matching of geographic features such as lakes and islands in vector data *** has been a significant development in that it has e

关键词： satellite imagery photogrammetric geometric accuracy radiometric accuracy large area mosaics automatic registration

Running Temperature and Mechanical stability of Grease as Maintenance Parameters of Railway Bearings

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International Journal of Automation and computing 2010年第2期7卷 160-166页

作者： Jan Lundberg Aditya Parida Peter sderholm Division of Operation and Maintenance Engineering Lule University of Technology

spherical roller bearings in railway car wheels are critical components whose failure may have catastrophic consequences. The present study aims to analyse the mechanical stability of greases and temperature of bearings as indicators for condition-based bearing maintenance. The performed case study includes nine fully-formulated commercial greases examined in the wheel bearings of five ore cars operated in northern scandinavia. The studied ore cars travelled a distance of about 300 000 km during a period of three years. small samples of the greases were taken on eight occasions to test their mechanical stability. In addition, the temperatures of the bearings were continuously recorded. After the test period, the wear, electrical damage, and corrosion of the bearings were examined. One of the findings is that the shear stress of the grease at a certain shear velocity （the certain yieldstress （CEY） value） is a good maintenance indicator and is highly dependent on the grease type. The bearing＇s wear, electrical damage and corrosion also depend on the grease type. However, no oxidation of the greases was identified. The paper also outlines a systematic methodology to determine an overall maintenance indicator for railway roller bearings which is based on the field measurements.

关键词： Maintenance mechanical stability railway roller bearings grease lubrication.

A conserved arbuscular mycorrhizal fungal core-species community colonizes potato roots in the Andes

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Fungal Diversity 2016年第2期77卷 317-333页

作者： Carolina senés-Guerrero Arthur schüßler Department of Biology GeneticsLudwig-Maximilians UniversityGrosshaderner Str.482152 PlaneggMartinsriedGermany

Plant-symbiotic arbuscular mycorrhizal fungi(AMF)are of high global ecological and economic importance,but describing environmental communities of AMF at the species level remains a challenge,despite the need to understand AMF-plant preferences and to apply AMF in sustainable ***,the potato-associated AMF species community composition was assessed for three Andean countries along an altitudinal gradient and at different plant stages,by using 454 Gs-FLX+sequencing of a 760 bp LsU rRNA gene PCR *** methods were compared:defining OTUs based on a simple sequence similarity threshold,or affiliating reference sequences to species based on a high throughput phylogenetic annotation approach using an evolutionary placement algorithm(EPA).The EPA-based approach was not only more precise,but also fundamental to robustly unveil the AMF species community *** principal advantage of this approach was also demonstrated by using artificially constructed datasets based on validated public database *** affiliation of sequence reads to species using phylogenetic annotation revealed a surprisingly conserved AMF core-species community structure in Andean potatoes,regardless of different plant stages and environmental *** total,41 species were detected and in some cases more than 25 species were found colonizing an individual root *** species were identified as dominant colonizers,co-occurring with Cetraspora nodosa and certain Claroideoglomus and Rhizophagus species in most potato root samples.

关键词： 454 pyrosequencing Andean ecosystems Arbuscular mycorrhizal fungi species communities DNA based species identification Evolutionary placement algorithm solanum tuberosum(potato)

Chinese guidelines for diagnosis and treatment of pancreatic cancer 2018(English version)

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Chinese Journal of Cancer Research 2019年第2期31卷 278-294页

作者： National Health Commission of the People's Republic of China National Health Commission of the People’s Republic of China

Pancreatic ductal adenocarcinoma is one of the common pancreatic neoplasms, with extremely high malignancy. The latest statistical data from National Cancer Center of China showed that the incidence of pancreatic cancer had increased dramatically from 2000 to 2011. In 2015, the incidence of pancreatic cancer in China ranked ninth among malignant tumors, and the mortality rate was the sixth in malignant tumors.

关键词： Pancreatic Chinese guidelines treatment

Gastrointestinal bleeding from Dieulafoy's lesion: Clinical presentation, endoscopic findings, and endoscopic therapy

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World Journal of Gastrointestinal Endoscopy 2015年第4期7卷 295-307页

作者： Borko Nojkov Mitchell s Cappell Division of Gastroenterology and Hepatology William Beaumont Hospital Oakland University William Beaumont school of Medicine

Although relatively uncommon, Dieulafoy's lesion is an important cause of acute gastrointestinal bleeding due to the frequent difficulty in its diagnosis; its tendency to cause severe, life-threatening, recurrent gastrointestinal bleeding; and its amenability to life-saving endoscopic therapy. Unlike normal vessels of the gastrointestinal tract which become progressively smaller in caliber peripherally, Dieulafoy's lesions maintain a large caliber despite their peripheral, submucosal, location within gastrointestinal wall. Dieulafoy's lesions typically present with severe, active, gastrointestinal bleeding, without prior symptoms; often cause hemodynamic instability and often require transfusion of multiple units of packed erythrocytes. About 75% of lesions are located in the stomach, with a marked proclivity of lesions within 6 cm of the gastroesophageal junction along the gastric lesser curve, but lesions can also occur in the duodenum and esophagus. Lesions in the jejunoileum or colorectum have been increasingly reported. Endoscopy is the first diagnostic test, but has only a 70% diagnostic yield because the lesions are frequently small and inconspicuous. Lesions typically appear at endoscopy as pigmented protuberances from exposed vessel stumps, with minimal surrounding erosion and no ulceration(visible vessel sans ulcer). Endoscopic therapy, including clips, sclerotherapy, argon plasma coagulation, thermocoagulation, or electrocoagulation, is the recommended initial therapy, with primary hemostasis achieved in nearly 90% of cases. Dual endoscopic therapy of epinephrine injection followed by ablative or mechanical therapy appears to be effective. Although banding is reportedly highly successful, it entails a small risk of gastrointestinal perforation from banding deep mural tissue. Therapeutic alternatives after failed endoscopic therapy include repeat endoscopic therapy, angiography, or surgical wedge resection. The mortality has declined from about 30% during

关键词： Dieulafoy's lesion Gastrointestinal bleeding

Combined signal Processing Based Techniques and Feed Forward Neural Networks for Pathological Voice Detection and Classification

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sound & Vibration 2021年第2期55卷 141-161页

作者： T.Jayasree s.Emerald shia Department of Electronics and Communication Engineering Government College of EngineeringTamil Nadu629007India Department of Electronics and Communication Engineering Cape Institute of TechnologyTamil Nadu629001India

This paper presents the pathological voice detection and classification techniques using signal processing based methodologies and Feed Forward Neural Networks(FFNN).The important pathological voices such as Autism spectrum Disorder(AsD)and Down syndrome(Ds)are considered for *** pathological voices are known to manifest in different ways in the speech of children and ***,it is possible to discriminate AsD and Ds children from normal ones using the acoustic features extracted from the speech of these *** important attributes hidden in the pathological voices are extracted by applying different signal processing *** this work,three group of feature vectors such as perturbation measures,noise parameters and spectral-cepstral modeling are derived from the *** detection and classification is done by means of Feed For-ward Neural Network(FFNN)classifier trained with scaled Conjugate Gradient(sCG)*** performance of the network is evaluated by finding various performance metrics and the the experimental results clearly demonstrate that the proposed method gives better performance compared with other methods discussed in the literature.

关键词： Autism spectrum disorder down syndrome feed forward neural network perturbation measures noise parameters cepstral features

C:N:P stoichiometry and nutrient limitation of the soil microbial biomass in a grazed grassland site under experimental P limitation or exces

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Ecological Processes 2012年第1期1卷 66-76页

作者： Bryan s Griffiths Annette spilles Michael Bonkowski Teagasc Environment Research CentreJohnstown CastleWexfordCoWexfordIreland Current address:sAC King's BuildingsWest Mains RoadEdinburgh EH93JGUK Mathematisch Naturwissenschaftliche Fakultät der Universität zu Köln Zoologisches Institut Abt.TerrestrischeÖkologieBiowissenschaftliches ZentrumOtto-Fischer-Str.6D-50674KölnGermany

Introduction:The availability of essential nutrients,such as nitrogen(N)and phosphorus(P),can feedback on soil carbon(C)and the soil microbial *** cycles can be supplemented by agricultural fertiliser addition,and we determined whether the stoichiometry and nutrient limitation of the microbial biomass could be affected by an unbalanced nutrient ***:samples were taken from a long-term trial(in effect since 1968)with annual applications of 0,15 and 30 kg P ha^(−1) with constant N and *** and microbial biomass CNP contents were measured and nutrient limitation assessed by substrate-induced *** regression and discriminant analyses were used to identify the variables explaining nutrient ***:soil and biomass CNP increased with increasing P fertiliser,and there was a significant,positive,correlation between microbial biomass P and biomass C,apart from at the highest level of P fertilisation when the microbial biomass was over-saturated with *** molar ratios of C:N:P in the microbial biomass remained constant(homeostatic)despite large changes in the soil nutrient *** growth was generally limited by C and N,except in soil with no added P when C and P were the main limiting nutrients.C,N and P,however,did not explain all the growth limitation on the soils with no added ***:Increased soil C and N were probably due to increased net primary *** results confirm that C:N:P ratios within the microbial biomass were constrained(***)under near optimum soil *** with no added P were characterised by strong microbial P limitation and soils under high P by over-saturation of microorganisms with *** changes in biomass C:P can be indicative of nutrient limitation within a site.

关键词： Carbon Nitrogen Nutrient limitation Phosphorus soil microbial biomass stoichiometry

Jackson,*** Modern shanghai:Colonialism in China's Global City

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Frontiers of History in China 2019年第4期14卷 634-639页

作者： Helena F.s.Lopes University of Bristol

Few cities in modern China have merited the degree of scholarly attention granted to *** Jackson's shaping M odem shanghai is a remarkably comprehensive study of the shanghai Municipal Council(sMC),which ran the International settlement,one of three cities within the city-the others being the French Concession and the Chinese *** other recent histories of institutions in modem China,this is one that takes a more global approach to the topic.

关键词： modem Cambridge granted