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Eocrinoid echinoderms from the Lower Cambrian Guanshan Fauna in Wuding,Yunnan,China

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Chinese Science Bulletin 2007年第5期52卷 717-719页

作者： HU ShiXue LUO HuiLin HOU ShuGuang Bernd-dietrich ERdTMANN Yunnan Institute of Geological Sciences Kunming 650011 China Technische Universitat Bedin D-13355 Berlin Germany

This is a brief report of a new occurrence of eocrinoids from the Early Cambrian Wulongqing Formation in Yunnan, China. The eocrinoids from the Guanshan fauna are among the earliest known eocrinoids. different from many other Early and Middle Cambrian eocrinoids, the Guanshan eocrinoids are char-acterized by the absence of sutural pores and epispires, the long and spiral brachioles, the extremely long stalk, and the ratio of the length of the stalk versus that of the calyx. The discovery of the eocri-noids from the Guanshan fauna not only provides new information to the investigation of the early evolution of this animal group, but also shed new light on the occurrence and migration of early eocrinoids.

关键词：棘皮类动物下寒武统关山动物群化石云南武定

Service life prediction of fly ash concrete using an artificial neural network

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Frontiers of Structural and Civil Engineering 2021年第3期15卷 793-805页

作者： Yasmina KELLOUCHE Mohamed GHRICI Bakhta BOUKHATEM Geomaterials Laboratory Hassiba Benbouali University of ChlefChlefAlgiers02000Algeria department of Civil Engineering University of SherbrookeSherbrookeJK 2R1Canada

Carbonation is one of the most aggressive phenomena affecting reinforced concrete structures and causing their degradation over *** reinforcement is altered by carbonation,the structure will no longer fulfill service *** this purpose,the present work estimates the lifetime of fly ash concrete by developing a carbonation depth prediction model that uses an artificial neural network technique.A collection of 300 data points was made from experimental results available in the published *** training of a three-layer perceptron was selected for the calculation of weights and biases of the network to reach the desired *** parameters affecting carbonation were used as input neurons:binder content,fly ash substitution rate,water/binder ratio,CO_(2)concentration,relative humidity,and concrete ***,experimental validation carried out for the developed model shows that the artificial neural network has strong potential as a feasible tool to accurately predict the carbonation depth of fly ash ***,a mathematical formula is proposed that can be used to successfully estimate the service life of fly ash concrete.

关键词： concrete fly ash carbonation neural networks experimental validation service life

Application of the dempster-Shafer Theory to the Classification of Pixels from Aster Satellite Images and Spectral Indices

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Journal of Applied Mathematics and Physics 2017年第7期5卷 1462-1477页

作者： Jean-Claude Okaingni Sié Ouattara Adles Francis Kouassi Adama Koné Wognin Joseph Vangah Alain Clement Laboratory of Signals and Electrical Systems (L2SE)) Institut National Polytechnique Houphou&eumlt Boigny Yamoussoukro Cote D’Ivoire Institut National Polytechnique Houphouët Boigny (INPHB) Yamoussoukro Cote D’Ivoire Ecole Supérieure des Technologies de l’Information et de la Communication (ESATIC) Abidjan Cote D’Ivoire Institut Universitaire de Technologie d’Angers (IUT) Angers France

In this paper, it is proposed to apply the dempster-Shafer Theory (dST) or the theory of evidence to map vegetation, aquatic and mineral surfaces with a view to detecting potential areas of observation of outcrops of geological formations (rocks, breastplates, regolith, etc.). The proposed approach consists in aggregating information by using the dST. From pretreated Aster satellite images (geo-referencing, geometric correction and resampling at 15 m), new channels were produced by determining the spectral indices NdVI, MNdWI and NdBaI. Then, the dST formalism was modeled and generated under the MATLAB software, an image segmented into six classes including three absolute classes (E,V,M) and three classes of confusion ({E,V}, {M,V}, {E,M}). The control on the land, based on geographic coordinates of pixels of different classes on said image, has made it possible to make a concordant interpretation thereof. Our contribution lies in taking into account imperfections (inaccuracies and uncertainties) related to source information by using mass functions based on a simple support model (two focal elements: the discernment framework and the potential set of belonging of the pixel to be classified) with a normal law for the good management of these.

关键词： dempster-Shafer Theory Belief Functions Source Modeling Aster Satellite Images Spectral Indices Classification

Robotics and mechatronics for planetary surface exploration

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Journal of Harbin Institute of Technology(New Series) 2003年第3期10卷 241-245页

作者： LIUH XIEZW GHIRZINGER RoboticResearchInstitute HarbinInstituteofTechnologyHarbin150001China dLROberpfaffenbofen GermanAerospaceCenterInstituteofRoboticsandMechatronicsD-82230WesslingGermany

The paper briefly addresses dLR' s ( German Aerospace Center) expertise in space robotics by handof corresponding milestone projects including systems on the International Space Station ISS. It then discussesthe key technologies needed for the development of an artificial "robonaut" generation with mechatronic ultra-light weight arms and multifingered hands. The third arm generation is nearly finished now, approaching thelimits of what is technologically achievable today with respect to light-weight and power losses. In a similar waydLR' s second generation of artificial 4-fingered hands was a big step towards higher reliability, manipulabilityand overall performance.

关键词： space-robotics light-weight robotics joint/torque control mechatronics

Plant breeding highlights master genes in major regulatory pathways

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Molecular Plant 2022年第3期15卷 391-392页

作者： delfina Barabaschi Luigi Cattivelli CREA Research Centre for Genomics and Bioinformatics Via San Protaso 302Fiorenzuola d’Arda 29017Italy

Bread wheat(Triticum aestivum),during its evolution,experienced severe genetic bottlenecks due to polyploidization and ***,breeding programs,triggered mainly by the Green Revolution within a narrow range of breeders'preferred parents,while increasing the global wheat productivity,produced a further and evident reduction of genetic diversity.A clear picture of the impact of domestication and breeding on genetic diversity was achieved after recent studies that highlight loci subjected to past or ongoing selection,described as selection signatures or selective sweeps.

关键词： breeding Plant signature

Superposition effect of passive inter-modulation for systems operating in multiple carriers

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The Journal of China Universities of Posts and Telecommunications 2013年第5期20卷 57-62页

作者： ZHAO Pei ZHANG Xu-pu YANG da-cheng Wireless Theory & Technology Laboratory Beijing University of Posts & Telecommunication R&d center Jointcom Communication Technology Co. Ltd

Nowadays, more carriers and components are used in cellular networks to satisfy the requirement of high-speed data service. The increase of carriers and components may result in serious problem of passive inter-modulation （PIM）. This paper investigates the superposition effect of 3rd-order and 5th-order PIM under multicarrier scenarios with the channelized scheme （CS） and the multiplexed scheme （MS）. We use the concept of ＇effective hit＇ and the cumulative inter-modulation factors （CIFs） to evaluate the cumulative PIM product strength on each individual carrier within the receive signal band. Furthermore, with the simulator based on Monte-Carlo method, the group inter-modulation factor （GIF） is calculated to measure the average superposition effect for multiple carriers compared with the benchmark case. The simulation results show that, compared with the CS, the strength of PIM product with the MS does not increases so greatly with the growth of the total number of the carriers. The results are useful for the component designers and the cellular network planners.

关键词： PIM superposition effect multicarrier

Measurement of neutron and charged particle fluxes toward earthquake prediction

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Earthquake Science 2017年第5期30卷 283-288页

作者： Asatulla U.Maksudov Mars A.Zufarov Physical-Technical Institute Academy of Sciences of Uzbekistan 2-bBodomzor Str.TashkentUzbekistan 100084

In this paper, we describe a possible method for predicting the earthquakes, which is based on simultaneous recording of the intensity of fluxes of neutrons and charged particles by detectors, commonly used in nuclear physics. These low-energy particles originate from radioactive nuclear processes in the Earth＇s crust. The variations in the particle flux intensity can be the precursor of the earth- quake. A description is given of an electronic installation that records the fluxes of charged particles in the radial direction, which are a possible response to the accumulated tectonic stresses in the Earth＇s crust. The obtained results showed an increase in the intensity of the fluxes for 10 or more hours before the occurrence of the earthquake. The previous version of the installation was able to indicate for the possibility of an earthquake （Maksudov et al. in Instrum Exp Tech 58：130-131, 2015）, but did not give information about the direction of the epicenter location. In this regard, the installation was modified by adding eight directional detectors. With the upgraded setup, we have received both the predictive signals, and signals determining the directions of the location of the forthcoming earthquake, starting 2-3 days before its origin.

关键词： detector Neutron flux·Charged particles ·Radioactive decay Earthquake

A matrix description of a wild category

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Science China Mathematics 1998年第5期41卷 461-475页

作者：张英伯雷天刚 department of Mathematics Beijing Normal University Beijing China Institute of Mathematics UNAM Ciudad University Mexico D. F. Mexico

A bocs A of representation wild type over an algebraically closed field k and its representation category R (A) are concretely described by using matrix method. It is proved that A has almost split sequences and strong homogeneous property in the case ch k =0. Thus there exists neither proper projective nor proper injective object in R (A). And for each indecomposable object M in R (A), there exists a proper almost split sequence, which is given explicitly.

关键词： representation wild type bocs representation category almost split sequence homogeneous.

亲情-责任交互式护理在骨科手术患者中的应用价值

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中国冶金工业医学杂志 2024年第3期41卷 292-292页

作者：丛英华辽健集团一五七医院辽宁2沈阳110045

目的探讨在骨科手术中应用亲情-责任交互式护理的效果。方法将于我院行骨科手术治疗的92例患者等分为参考组和干预组,并予以不同护理。比较两组健康知识掌握度、VAS评分、自我效能感评分、护理满意度、生活质量评分和配合度。结果干预... 详细信息

目的探讨在骨科手术中应用亲情-责任交互式护理的效果。方法将于我院行骨科手术治疗的92例患者等分为参考组和干预组,并予以不同护理。比较两组健康知识掌握度、VAS评分、自我效能感评分、护理满意度、生活质量评分和配合度。结果干预组健康知识掌握度、VAS评分、自我效能感评分、护理满意度、生活质量评分和配合度均优于参考组,组间差异显著(均P<0.05)。结论在骨科手术患者中采用亲情-责任交互式护理,能够提高患者疾病知识掌握度、自我效能感、护理满意度及生活质量,可减轻患者疼痛感。

关键词：骨科手术亲情-责任交互式护理